linux/drivers/md/md.c
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   1/*
   2   md.c : Multiple Devices driver for Linux
   3          Copyright (C) 1998, 1999, 2000 Ingo Molnar
   4
   5     completely rewritten, based on the MD driver code from Marc Zyngier
   6
   7   Changes:
   8
   9   - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
  10   - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
  11   - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
  12   - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
  13   - kmod support by: Cyrus Durgin
  14   - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
  15   - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
  16
  17   - lots of fixes and improvements to the RAID1/RAID5 and generic
  18     RAID code (such as request based resynchronization):
  19
  20     Neil Brown <neilb@cse.unsw.edu.au>.
  21
  22   - persistent bitmap code
  23     Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
  24
  25   This program is free software; you can redistribute it and/or modify
  26   it under the terms of the GNU General Public License as published by
  27   the Free Software Foundation; either version 2, or (at your option)
  28   any later version.
  29
  30   You should have received a copy of the GNU General Public License
  31   (for example /usr/src/linux/COPYING); if not, write to the Free
  32   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33*/
  34
  35#include <linux/kthread.h>
  36#include <linux/blkdev.h>
  37#include <linux/sysctl.h>
  38#include <linux/seq_file.h>
  39#include <linux/fs.h>
  40#include <linux/poll.h>
  41#include <linux/ctype.h>
  42#include <linux/string.h>
  43#include <linux/hdreg.h>
  44#include <linux/proc_fs.h>
  45#include <linux/random.h>
  46#include <linux/module.h>
  47#include <linux/reboot.h>
  48#include <linux/file.h>
  49#include <linux/compat.h>
  50#include <linux/delay.h>
  51#include <linux/raid/md_p.h>
  52#include <linux/raid/md_u.h>
  53#include <linux/slab.h>
  54#include "md.h"
  55#include "bitmap.h"
  56
  57#ifndef MODULE
  58static void autostart_arrays(int part);
  59#endif
  60
  61/* pers_list is a list of registered personalities protected
  62 * by pers_lock.
  63 * pers_lock does extra service to protect accesses to
  64 * mddev->thread when the mutex cannot be held.
  65 */
  66static LIST_HEAD(pers_list);
  67static DEFINE_SPINLOCK(pers_lock);
  68
  69static void md_print_devices(void);
  70
  71static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
  72static struct workqueue_struct *md_wq;
  73static struct workqueue_struct *md_misc_wq;
  74
  75#define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
  76
  77/*
  78 * Default number of read corrections we'll attempt on an rdev
  79 * before ejecting it from the array. We divide the read error
  80 * count by 2 for every hour elapsed between read errors.
  81 */
  82#define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
  83/*
  84 * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
  85 * is 1000 KB/sec, so the extra system load does not show up that much.
  86 * Increase it if you want to have more _guaranteed_ speed. Note that
  87 * the RAID driver will use the maximum available bandwidth if the IO
  88 * subsystem is idle. There is also an 'absolute maximum' reconstruction
  89 * speed limit - in case reconstruction slows down your system despite
  90 * idle IO detection.
  91 *
  92 * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
  93 * or /sys/block/mdX/md/sync_speed_{min,max}
  94 */
  95
  96static int sysctl_speed_limit_min = 1000;
  97static int sysctl_speed_limit_max = 200000;
  98static inline int speed_min(struct mddev *mddev)
  99{
 100        return mddev->sync_speed_min ?
 101                mddev->sync_speed_min : sysctl_speed_limit_min;
 102}
 103
 104static inline int speed_max(struct mddev *mddev)
 105{
 106        return mddev->sync_speed_max ?
 107                mddev->sync_speed_max : sysctl_speed_limit_max;
 108}
 109
 110static struct ctl_table_header *raid_table_header;
 111
 112static ctl_table raid_table[] = {
 113        {
 114                .procname       = "speed_limit_min",
 115                .data           = &sysctl_speed_limit_min,
 116                .maxlen         = sizeof(int),
 117                .mode           = S_IRUGO|S_IWUSR,
 118                .proc_handler   = proc_dointvec,
 119        },
 120        {
 121                .procname       = "speed_limit_max",
 122                .data           = &sysctl_speed_limit_max,
 123                .maxlen         = sizeof(int),
 124                .mode           = S_IRUGO|S_IWUSR,
 125                .proc_handler   = proc_dointvec,
 126        },
 127        { }
 128};
 129
 130static ctl_table raid_dir_table[] = {
 131        {
 132                .procname       = "raid",
 133                .maxlen         = 0,
 134                .mode           = S_IRUGO|S_IXUGO,
 135                .child          = raid_table,
 136        },
 137        { }
 138};
 139
 140static ctl_table raid_root_table[] = {
 141        {
 142                .procname       = "dev",
 143                .maxlen         = 0,
 144                .mode           = 0555,
 145                .child          = raid_dir_table,
 146        },
 147        {  }
 148};
 149
 150static const struct block_device_operations md_fops;
 151
 152static int start_readonly;
 153
 154/* bio_clone_mddev
 155 * like bio_clone, but with a local bio set
 156 */
 157
 158static void mddev_bio_destructor(struct bio *bio)
 159{
 160        struct mddev *mddev, **mddevp;
 161
 162        mddevp = (void*)bio;
 163        mddev = mddevp[-1];
 164
 165        bio_free(bio, mddev->bio_set);
 166}
 167
 168struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
 169                            struct mddev *mddev)
 170{
 171        struct bio *b;
 172        struct mddev **mddevp;
 173
 174        if (!mddev || !mddev->bio_set)
 175                return bio_alloc(gfp_mask, nr_iovecs);
 176
 177        b = bio_alloc_bioset(gfp_mask, nr_iovecs,
 178                             mddev->bio_set);
 179        if (!b)
 180                return NULL;
 181        mddevp = (void*)b;
 182        mddevp[-1] = mddev;
 183        b->bi_destructor = mddev_bio_destructor;
 184        return b;
 185}
 186EXPORT_SYMBOL_GPL(bio_alloc_mddev);
 187
 188struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
 189                            struct mddev *mddev)
 190{
 191        struct bio *b;
 192        struct mddev **mddevp;
 193
 194        if (!mddev || !mddev->bio_set)
 195                return bio_clone(bio, gfp_mask);
 196
 197        b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs,
 198                             mddev->bio_set);
 199        if (!b)
 200                return NULL;
 201        mddevp = (void*)b;
 202        mddevp[-1] = mddev;
 203        b->bi_destructor = mddev_bio_destructor;
 204        __bio_clone(b, bio);
 205        if (bio_integrity(bio)) {
 206                int ret;
 207
 208                ret = bio_integrity_clone(b, bio, gfp_mask, mddev->bio_set);
 209
 210                if (ret < 0) {
 211                        bio_put(b);
 212                        return NULL;
 213                }
 214        }
 215
 216        return b;
 217}
 218EXPORT_SYMBOL_GPL(bio_clone_mddev);
 219
 220void md_trim_bio(struct bio *bio, int offset, int size)
 221{
 222        /* 'bio' is a cloned bio which we need to trim to match
 223         * the given offset and size.
 224         * This requires adjusting bi_sector, bi_size, and bi_io_vec
 225         */
 226        int i;
 227        struct bio_vec *bvec;
 228        int sofar = 0;
 229
 230        size <<= 9;
 231        if (offset == 0 && size == bio->bi_size)
 232                return;
 233
 234        bio->bi_sector += offset;
 235        bio->bi_size = size;
 236        offset <<= 9;
 237        clear_bit(BIO_SEG_VALID, &bio->bi_flags);
 238
 239        while (bio->bi_idx < bio->bi_vcnt &&
 240               bio->bi_io_vec[bio->bi_idx].bv_len <= offset) {
 241                /* remove this whole bio_vec */
 242                offset -= bio->bi_io_vec[bio->bi_idx].bv_len;
 243                bio->bi_idx++;
 244        }
 245        if (bio->bi_idx < bio->bi_vcnt) {
 246                bio->bi_io_vec[bio->bi_idx].bv_offset += offset;
 247                bio->bi_io_vec[bio->bi_idx].bv_len -= offset;
 248        }
 249        /* avoid any complications with bi_idx being non-zero*/
 250        if (bio->bi_idx) {
 251                memmove(bio->bi_io_vec, bio->bi_io_vec+bio->bi_idx,
 252                        (bio->bi_vcnt - bio->bi_idx) * sizeof(struct bio_vec));
 253                bio->bi_vcnt -= bio->bi_idx;
 254                bio->bi_idx = 0;
 255        }
 256        /* Make sure vcnt and last bv are not too big */
 257        bio_for_each_segment(bvec, bio, i) {
 258                if (sofar + bvec->bv_len > size)
 259                        bvec->bv_len = size - sofar;
 260                if (bvec->bv_len == 0) {
 261                        bio->bi_vcnt = i;
 262                        break;
 263                }
 264                sofar += bvec->bv_len;
 265        }
 266}
 267EXPORT_SYMBOL_GPL(md_trim_bio);
 268
 269/*
 270 * We have a system wide 'event count' that is incremented
 271 * on any 'interesting' event, and readers of /proc/mdstat
 272 * can use 'poll' or 'select' to find out when the event
 273 * count increases.
 274 *
 275 * Events are:
 276 *  start array, stop array, error, add device, remove device,
 277 *  start build, activate spare
 278 */
 279static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
 280static atomic_t md_event_count;
 281void md_new_event(struct mddev *mddev)
 282{
 283        atomic_inc(&md_event_count);
 284        wake_up(&md_event_waiters);
 285}
 286EXPORT_SYMBOL_GPL(md_new_event);
 287
 288/* Alternate version that can be called from interrupts
 289 * when calling sysfs_notify isn't needed.
 290 */
 291static void md_new_event_inintr(struct mddev *mddev)
 292{
 293        atomic_inc(&md_event_count);
 294        wake_up(&md_event_waiters);
 295}
 296
 297/*
 298 * Enables to iterate over all existing md arrays
 299 * all_mddevs_lock protects this list.
 300 */
 301static LIST_HEAD(all_mddevs);
 302static DEFINE_SPINLOCK(all_mddevs_lock);
 303
 304
 305/*
 306 * iterates through all used mddevs in the system.
 307 * We take care to grab the all_mddevs_lock whenever navigating
 308 * the list, and to always hold a refcount when unlocked.
 309 * Any code which breaks out of this loop while own
 310 * a reference to the current mddev and must mddev_put it.
 311 */
 312#define for_each_mddev(_mddev,_tmp)                                     \
 313                                                                        \
 314        for (({ spin_lock(&all_mddevs_lock);                            \
 315                _tmp = all_mddevs.next;                                 \
 316                _mddev = NULL;});                                       \
 317             ({ if (_tmp != &all_mddevs)                                \
 318                        mddev_get(list_entry(_tmp, struct mddev, all_mddevs));\
 319                spin_unlock(&all_mddevs_lock);                          \
 320                if (_mddev) mddev_put(_mddev);                          \
 321                _mddev = list_entry(_tmp, struct mddev, all_mddevs);    \
 322                _tmp != &all_mddevs;});                                 \
 323             ({ spin_lock(&all_mddevs_lock);                            \
 324                _tmp = _tmp->next;})                                    \
 325                )
 326
 327
 328/* Rather than calling directly into the personality make_request function,
 329 * IO requests come here first so that we can check if the device is
 330 * being suspended pending a reconfiguration.
 331 * We hold a refcount over the call to ->make_request.  By the time that
 332 * call has finished, the bio has been linked into some internal structure
 333 * and so is visible to ->quiesce(), so we don't need the refcount any more.
 334 */
 335static void md_make_request(struct request_queue *q, struct bio *bio)
 336{
 337        const int rw = bio_data_dir(bio);
 338        struct mddev *mddev = q->queuedata;
 339        int cpu;
 340        unsigned int sectors;
 341
 342        if (mddev == NULL || mddev->pers == NULL
 343            || !mddev->ready) {
 344                bio_io_error(bio);
 345                return;
 346        }
 347        smp_rmb(); /* Ensure implications of  'active' are visible */
 348        rcu_read_lock();
 349        if (mddev->suspended) {
 350                DEFINE_WAIT(__wait);
 351                for (;;) {
 352                        prepare_to_wait(&mddev->sb_wait, &__wait,
 353                                        TASK_UNINTERRUPTIBLE);
 354                        if (!mddev->suspended)
 355                                break;
 356                        rcu_read_unlock();
 357                        schedule();
 358                        rcu_read_lock();
 359                }
 360                finish_wait(&mddev->sb_wait, &__wait);
 361        }
 362        atomic_inc(&mddev->active_io);
 363        rcu_read_unlock();
 364
 365        /*
 366         * save the sectors now since our bio can
 367         * go away inside make_request
 368         */
 369        sectors = bio_sectors(bio);
 370        mddev->pers->make_request(mddev, bio);
 371
 372        cpu = part_stat_lock();
 373        part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
 374        part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], sectors);
 375        part_stat_unlock();
 376
 377        if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
 378                wake_up(&mddev->sb_wait);
 379}
 380
 381/* mddev_suspend makes sure no new requests are submitted
 382 * to the device, and that any requests that have been submitted
 383 * are completely handled.
 384 * Once ->stop is called and completes, the module will be completely
 385 * unused.
 386 */
 387void mddev_suspend(struct mddev *mddev)
 388{
 389        BUG_ON(mddev->suspended);
 390        mddev->suspended = 1;
 391        synchronize_rcu();
 392        wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
 393        mddev->pers->quiesce(mddev, 1);
 394}
 395EXPORT_SYMBOL_GPL(mddev_suspend);
 396
 397void mddev_resume(struct mddev *mddev)
 398{
 399        mddev->suspended = 0;
 400        wake_up(&mddev->sb_wait);
 401        mddev->pers->quiesce(mddev, 0);
 402
 403        md_wakeup_thread(mddev->thread);
 404        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 405}
 406EXPORT_SYMBOL_GPL(mddev_resume);
 407
 408int mddev_congested(struct mddev *mddev, int bits)
 409{
 410        return mddev->suspended;
 411}
 412EXPORT_SYMBOL(mddev_congested);
 413
 414/*
 415 * Generic flush handling for md
 416 */
 417
 418static void md_end_flush(struct bio *bio, int err)
 419{
 420        struct md_rdev *rdev = bio->bi_private;
 421        struct mddev *mddev = rdev->mddev;
 422
 423        rdev_dec_pending(rdev, mddev);
 424
 425        if (atomic_dec_and_test(&mddev->flush_pending)) {
 426                /* The pre-request flush has finished */
 427                queue_work(md_wq, &mddev->flush_work);
 428        }
 429        bio_put(bio);
 430}
 431
 432static void md_submit_flush_data(struct work_struct *ws);
 433
 434static void submit_flushes(struct work_struct *ws)
 435{
 436        struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 437        struct md_rdev *rdev;
 438
 439        INIT_WORK(&mddev->flush_work, md_submit_flush_data);
 440        atomic_set(&mddev->flush_pending, 1);
 441        rcu_read_lock();
 442        list_for_each_entry_rcu(rdev, &mddev->disks, same_set)
 443                if (rdev->raid_disk >= 0 &&
 444                    !test_bit(Faulty, &rdev->flags)) {
 445                        /* Take two references, one is dropped
 446                         * when request finishes, one after
 447                         * we reclaim rcu_read_lock
 448                         */
 449                        struct bio *bi;
 450                        atomic_inc(&rdev->nr_pending);
 451                        atomic_inc(&rdev->nr_pending);
 452                        rcu_read_unlock();
 453                        bi = bio_alloc_mddev(GFP_KERNEL, 0, mddev);
 454                        bi->bi_end_io = md_end_flush;
 455                        bi->bi_private = rdev;
 456                        bi->bi_bdev = rdev->bdev;
 457                        atomic_inc(&mddev->flush_pending);
 458                        submit_bio(WRITE_FLUSH, bi);
 459                        rcu_read_lock();
 460                        rdev_dec_pending(rdev, mddev);
 461                }
 462        rcu_read_unlock();
 463        if (atomic_dec_and_test(&mddev->flush_pending))
 464                queue_work(md_wq, &mddev->flush_work);
 465}
 466
 467static void md_submit_flush_data(struct work_struct *ws)
 468{
 469        struct mddev *mddev = container_of(ws, struct mddev, flush_work);
 470        struct bio *bio = mddev->flush_bio;
 471
 472        if (bio->bi_size == 0)
 473                /* an empty barrier - all done */
 474                bio_endio(bio, 0);
 475        else {
 476                bio->bi_rw &= ~REQ_FLUSH;
 477                mddev->pers->make_request(mddev, bio);
 478        }
 479
 480        mddev->flush_bio = NULL;
 481        wake_up(&mddev->sb_wait);
 482}
 483
 484void md_flush_request(struct mddev *mddev, struct bio *bio)
 485{
 486        spin_lock_irq(&mddev->write_lock);
 487        wait_event_lock_irq(mddev->sb_wait,
 488                            !mddev->flush_bio,
 489                            mddev->write_lock, /*nothing*/);
 490        mddev->flush_bio = bio;
 491        spin_unlock_irq(&mddev->write_lock);
 492
 493        INIT_WORK(&mddev->flush_work, submit_flushes);
 494        queue_work(md_wq, &mddev->flush_work);
 495}
 496EXPORT_SYMBOL(md_flush_request);
 497
 498/* Support for plugging.
 499 * This mirrors the plugging support in request_queue, but does not
 500 * require having a whole queue or request structures.
 501 * We allocate an md_plug_cb for each md device and each thread it gets
 502 * plugged on.  This links tot the private plug_handle structure in the
 503 * personality data where we keep a count of the number of outstanding
 504 * plugs so other code can see if a plug is active.
 505 */
 506struct md_plug_cb {
 507        struct blk_plug_cb cb;
 508        struct mddev *mddev;
 509};
 510
 511static void plugger_unplug(struct blk_plug_cb *cb)
 512{
 513        struct md_plug_cb *mdcb = container_of(cb, struct md_plug_cb, cb);
 514        if (atomic_dec_and_test(&mdcb->mddev->plug_cnt))
 515                md_wakeup_thread(mdcb->mddev->thread);
 516        kfree(mdcb);
 517}
 518
 519/* Check that an unplug wakeup will come shortly.
 520 * If not, wakeup the md thread immediately
 521 */
 522int mddev_check_plugged(struct mddev *mddev)
 523{
 524        struct blk_plug *plug = current->plug;
 525        struct md_plug_cb *mdcb;
 526
 527        if (!plug)
 528                return 0;
 529
 530        list_for_each_entry(mdcb, &plug->cb_list, cb.list) {
 531                if (mdcb->cb.callback == plugger_unplug &&
 532                    mdcb->mddev == mddev) {
 533                        /* Already on the list, move to top */
 534                        if (mdcb != list_first_entry(&plug->cb_list,
 535                                                    struct md_plug_cb,
 536                                                    cb.list))
 537                                list_move(&mdcb->cb.list, &plug->cb_list);
 538                        return 1;
 539                }
 540        }
 541        /* Not currently on the callback list */
 542        mdcb = kmalloc(sizeof(*mdcb), GFP_ATOMIC);
 543        if (!mdcb)
 544                return 0;
 545
 546        mdcb->mddev = mddev;
 547        mdcb->cb.callback = plugger_unplug;
 548        atomic_inc(&mddev->plug_cnt);
 549        list_add(&mdcb->cb.list, &plug->cb_list);
 550        return 1;
 551}
 552EXPORT_SYMBOL_GPL(mddev_check_plugged);
 553
 554static inline struct mddev *mddev_get(struct mddev *mddev)
 555{
 556        atomic_inc(&mddev->active);
 557        return mddev;
 558}
 559
 560static void mddev_delayed_delete(struct work_struct *ws);
 561
 562static void mddev_put(struct mddev *mddev)
 563{
 564        struct bio_set *bs = NULL;
 565
 566        if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
 567                return;
 568        if (!mddev->raid_disks && list_empty(&mddev->disks) &&
 569            mddev->ctime == 0 && !mddev->hold_active) {
 570                /* Array is not configured at all, and not held active,
 571                 * so destroy it */
 572                list_del_init(&mddev->all_mddevs);
 573                bs = mddev->bio_set;
 574                mddev->bio_set = NULL;
 575                if (mddev->gendisk) {
 576                        /* We did a probe so need to clean up.  Call
 577                         * queue_work inside the spinlock so that
 578                         * flush_workqueue() after mddev_find will
 579                         * succeed in waiting for the work to be done.
 580                         */
 581                        INIT_WORK(&mddev->del_work, mddev_delayed_delete);
 582                        queue_work(md_misc_wq, &mddev->del_work);
 583                } else
 584                        kfree(mddev);
 585        }
 586        spin_unlock(&all_mddevs_lock);
 587        if (bs)
 588                bioset_free(bs);
 589}
 590
 591void mddev_init(struct mddev *mddev)
 592{
 593        mutex_init(&mddev->open_mutex);
 594        mutex_init(&mddev->reconfig_mutex);
 595        mutex_init(&mddev->bitmap_info.mutex);
 596        INIT_LIST_HEAD(&mddev->disks);
 597        INIT_LIST_HEAD(&mddev->all_mddevs);
 598        init_timer(&mddev->safemode_timer);
 599        atomic_set(&mddev->active, 1);
 600        atomic_set(&mddev->openers, 0);
 601        atomic_set(&mddev->active_io, 0);
 602        atomic_set(&mddev->plug_cnt, 0);
 603        spin_lock_init(&mddev->write_lock);
 604        atomic_set(&mddev->flush_pending, 0);
 605        init_waitqueue_head(&mddev->sb_wait);
 606        init_waitqueue_head(&mddev->recovery_wait);
 607        mddev->reshape_position = MaxSector;
 608        mddev->resync_min = 0;
 609        mddev->resync_max = MaxSector;
 610        mddev->level = LEVEL_NONE;
 611}
 612EXPORT_SYMBOL_GPL(mddev_init);
 613
 614static struct mddev * mddev_find(dev_t unit)
 615{
 616        struct mddev *mddev, *new = NULL;
 617
 618        if (unit && MAJOR(unit) != MD_MAJOR)
 619                unit &= ~((1<<MdpMinorShift)-1);
 620
 621 retry:
 622        spin_lock(&all_mddevs_lock);
 623
 624        if (unit) {
 625                list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 626                        if (mddev->unit == unit) {
 627                                mddev_get(mddev);
 628                                spin_unlock(&all_mddevs_lock);
 629                                kfree(new);
 630                                return mddev;
 631                        }
 632
 633                if (new) {
 634                        list_add(&new->all_mddevs, &all_mddevs);
 635                        spin_unlock(&all_mddevs_lock);
 636                        new->hold_active = UNTIL_IOCTL;
 637                        return new;
 638                }
 639        } else if (new) {
 640                /* find an unused unit number */
 641                static int next_minor = 512;
 642                int start = next_minor;
 643                int is_free = 0;
 644                int dev = 0;
 645                while (!is_free) {
 646                        dev = MKDEV(MD_MAJOR, next_minor);
 647                        next_minor++;
 648                        if (next_minor > MINORMASK)
 649                                next_minor = 0;
 650                        if (next_minor == start) {
 651                                /* Oh dear, all in use. */
 652                                spin_unlock(&all_mddevs_lock);
 653                                kfree(new);
 654                                return NULL;
 655                        }
 656                                
 657                        is_free = 1;
 658                        list_for_each_entry(mddev, &all_mddevs, all_mddevs)
 659                                if (mddev->unit == dev) {
 660                                        is_free = 0;
 661                                        break;
 662                                }
 663                }
 664                new->unit = dev;
 665                new->md_minor = MINOR(dev);
 666                new->hold_active = UNTIL_STOP;
 667                list_add(&new->all_mddevs, &all_mddevs);
 668                spin_unlock(&all_mddevs_lock);
 669                return new;
 670        }
 671        spin_unlock(&all_mddevs_lock);
 672
 673        new = kzalloc(sizeof(*new), GFP_KERNEL);
 674        if (!new)
 675                return NULL;
 676
 677        new->unit = unit;
 678        if (MAJOR(unit) == MD_MAJOR)
 679                new->md_minor = MINOR(unit);
 680        else
 681                new->md_minor = MINOR(unit) >> MdpMinorShift;
 682
 683        mddev_init(new);
 684
 685        goto retry;
 686}
 687
 688static inline int mddev_lock(struct mddev * mddev)
 689{
 690        return mutex_lock_interruptible(&mddev->reconfig_mutex);
 691}
 692
 693static inline int mddev_is_locked(struct mddev *mddev)
 694{
 695        return mutex_is_locked(&mddev->reconfig_mutex);
 696}
 697
 698static inline int mddev_trylock(struct mddev * mddev)
 699{
 700        return mutex_trylock(&mddev->reconfig_mutex);
 701}
 702
 703static struct attribute_group md_redundancy_group;
 704
 705static void mddev_unlock(struct mddev * mddev)
 706{
 707        if (mddev->to_remove) {
 708                /* These cannot be removed under reconfig_mutex as
 709                 * an access to the files will try to take reconfig_mutex
 710                 * while holding the file unremovable, which leads to
 711                 * a deadlock.
 712                 * So hold set sysfs_active while the remove in happeing,
 713                 * and anything else which might set ->to_remove or my
 714                 * otherwise change the sysfs namespace will fail with
 715                 * -EBUSY if sysfs_active is still set.
 716                 * We set sysfs_active under reconfig_mutex and elsewhere
 717                 * test it under the same mutex to ensure its correct value
 718                 * is seen.
 719                 */
 720                struct attribute_group *to_remove = mddev->to_remove;
 721                mddev->to_remove = NULL;
 722                mddev->sysfs_active = 1;
 723                mutex_unlock(&mddev->reconfig_mutex);
 724
 725                if (mddev->kobj.sd) {
 726                        if (to_remove != &md_redundancy_group)
 727                                sysfs_remove_group(&mddev->kobj, to_remove);
 728                        if (mddev->pers == NULL ||
 729                            mddev->pers->sync_request == NULL) {
 730                                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
 731                                if (mddev->sysfs_action)
 732                                        sysfs_put(mddev->sysfs_action);
 733                                mddev->sysfs_action = NULL;
 734                        }
 735                }
 736                mddev->sysfs_active = 0;
 737        } else
 738                mutex_unlock(&mddev->reconfig_mutex);
 739
 740        /* As we've dropped the mutex we need a spinlock to
 741         * make sure the thread doesn't disappear
 742         */
 743        spin_lock(&pers_lock);
 744        md_wakeup_thread(mddev->thread);
 745        spin_unlock(&pers_lock);
 746}
 747
 748static struct md_rdev * find_rdev_nr(struct mddev *mddev, int nr)
 749{
 750        struct md_rdev *rdev;
 751
 752        list_for_each_entry(rdev, &mddev->disks, same_set)
 753                if (rdev->desc_nr == nr)
 754                        return rdev;
 755
 756        return NULL;
 757}
 758
 759static struct md_rdev * find_rdev(struct mddev * mddev, dev_t dev)
 760{
 761        struct md_rdev *rdev;
 762
 763        list_for_each_entry(rdev, &mddev->disks, same_set)
 764                if (rdev->bdev->bd_dev == dev)
 765                        return rdev;
 766
 767        return NULL;
 768}
 769
 770static struct md_personality *find_pers(int level, char *clevel)
 771{
 772        struct md_personality *pers;
 773        list_for_each_entry(pers, &pers_list, list) {
 774                if (level != LEVEL_NONE && pers->level == level)
 775                        return pers;
 776                if (strcmp(pers->name, clevel)==0)
 777                        return pers;
 778        }
 779        return NULL;
 780}
 781
 782/* return the offset of the super block in 512byte sectors */
 783static inline sector_t calc_dev_sboffset(struct md_rdev *rdev)
 784{
 785        sector_t num_sectors = i_size_read(rdev->bdev->bd_inode) / 512;
 786        return MD_NEW_SIZE_SECTORS(num_sectors);
 787}
 788
 789static int alloc_disk_sb(struct md_rdev * rdev)
 790{
 791        if (rdev->sb_page)
 792                MD_BUG();
 793
 794        rdev->sb_page = alloc_page(GFP_KERNEL);
 795        if (!rdev->sb_page) {
 796                printk(KERN_ALERT "md: out of memory.\n");
 797                return -ENOMEM;
 798        }
 799
 800        return 0;
 801}
 802
 803static void free_disk_sb(struct md_rdev * rdev)
 804{
 805        if (rdev->sb_page) {
 806                put_page(rdev->sb_page);
 807                rdev->sb_loaded = 0;
 808                rdev->sb_page = NULL;
 809                rdev->sb_start = 0;
 810                rdev->sectors = 0;
 811        }
 812        if (rdev->bb_page) {
 813                put_page(rdev->bb_page);
 814                rdev->bb_page = NULL;
 815        }
 816}
 817
 818
 819static void super_written(struct bio *bio, int error)
 820{
 821        struct md_rdev *rdev = bio->bi_private;
 822        struct mddev *mddev = rdev->mddev;
 823
 824        if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags)) {
 825                printk("md: super_written gets error=%d, uptodate=%d\n",
 826                       error, test_bit(BIO_UPTODATE, &bio->bi_flags));
 827                WARN_ON(test_bit(BIO_UPTODATE, &bio->bi_flags));
 828                md_error(mddev, rdev);
 829        }
 830
 831        if (atomic_dec_and_test(&mddev->pending_writes))
 832                wake_up(&mddev->sb_wait);
 833        bio_put(bio);
 834}
 835
 836void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
 837                   sector_t sector, int size, struct page *page)
 838{
 839        /* write first size bytes of page to sector of rdev
 840         * Increment mddev->pending_writes before returning
 841         * and decrement it on completion, waking up sb_wait
 842         * if zero is reached.
 843         * If an error occurred, call md_error
 844         */
 845        struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, mddev);
 846
 847        bio->bi_bdev = rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev;
 848        bio->bi_sector = sector;
 849        bio_add_page(bio, page, size, 0);
 850        bio->bi_private = rdev;
 851        bio->bi_end_io = super_written;
 852
 853        atomic_inc(&mddev->pending_writes);
 854        submit_bio(WRITE_FLUSH_FUA, bio);
 855}
 856
 857void md_super_wait(struct mddev *mddev)
 858{
 859        /* wait for all superblock writes that were scheduled to complete */
 860        DEFINE_WAIT(wq);
 861        for(;;) {
 862                prepare_to_wait(&mddev->sb_wait, &wq, TASK_UNINTERRUPTIBLE);
 863                if (atomic_read(&mddev->pending_writes)==0)
 864                        break;
 865                schedule();
 866        }
 867        finish_wait(&mddev->sb_wait, &wq);
 868}
 869
 870static void bi_complete(struct bio *bio, int error)
 871{
 872        complete((struct completion*)bio->bi_private);
 873}
 874
 875int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
 876                 struct page *page, int rw, bool metadata_op)
 877{
 878        struct bio *bio = bio_alloc_mddev(GFP_NOIO, 1, rdev->mddev);
 879        struct completion event;
 880        int ret;
 881
 882        rw |= REQ_SYNC;
 883
 884        bio->bi_bdev = (metadata_op && rdev->meta_bdev) ?
 885                rdev->meta_bdev : rdev->bdev;
 886        if (metadata_op)
 887                bio->bi_sector = sector + rdev->sb_start;
 888        else
 889                bio->bi_sector = sector + rdev->data_offset;
 890        bio_add_page(bio, page, size, 0);
 891        init_completion(&event);
 892        bio->bi_private = &event;
 893        bio->bi_end_io = bi_complete;
 894        submit_bio(rw, bio);
 895        wait_for_completion(&event);
 896
 897        ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
 898        bio_put(bio);
 899        return ret;
 900}
 901EXPORT_SYMBOL_GPL(sync_page_io);
 902
 903static int read_disk_sb(struct md_rdev * rdev, int size)
 904{
 905        char b[BDEVNAME_SIZE];
 906        if (!rdev->sb_page) {
 907                MD_BUG();
 908                return -EINVAL;
 909        }
 910        if (rdev->sb_loaded)
 911                return 0;
 912
 913
 914        if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, true))
 915                goto fail;
 916        rdev->sb_loaded = 1;
 917        return 0;
 918
 919fail:
 920        printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
 921                bdevname(rdev->bdev,b));
 922        return -EINVAL;
 923}
 924
 925static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 926{
 927        return  sb1->set_uuid0 == sb2->set_uuid0 &&
 928                sb1->set_uuid1 == sb2->set_uuid1 &&
 929                sb1->set_uuid2 == sb2->set_uuid2 &&
 930                sb1->set_uuid3 == sb2->set_uuid3;
 931}
 932
 933static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
 934{
 935        int ret;
 936        mdp_super_t *tmp1, *tmp2;
 937
 938        tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
 939        tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
 940
 941        if (!tmp1 || !tmp2) {
 942                ret = 0;
 943                printk(KERN_INFO "md.c sb_equal(): failed to allocate memory!\n");
 944                goto abort;
 945        }
 946
 947        *tmp1 = *sb1;
 948        *tmp2 = *sb2;
 949
 950        /*
 951         * nr_disks is not constant
 952         */
 953        tmp1->nr_disks = 0;
 954        tmp2->nr_disks = 0;
 955
 956        ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
 957abort:
 958        kfree(tmp1);
 959        kfree(tmp2);
 960        return ret;
 961}
 962
 963
 964static u32 md_csum_fold(u32 csum)
 965{
 966        csum = (csum & 0xffff) + (csum >> 16);
 967        return (csum & 0xffff) + (csum >> 16);
 968}
 969
 970static unsigned int calc_sb_csum(mdp_super_t * sb)
 971{
 972        u64 newcsum = 0;
 973        u32 *sb32 = (u32*)sb;
 974        int i;
 975        unsigned int disk_csum, csum;
 976
 977        disk_csum = sb->sb_csum;
 978        sb->sb_csum = 0;
 979
 980        for (i = 0; i < MD_SB_BYTES/4 ; i++)
 981                newcsum += sb32[i];
 982        csum = (newcsum & 0xffffffff) + (newcsum>>32);
 983
 984
 985#ifdef CONFIG_ALPHA
 986        /* This used to use csum_partial, which was wrong for several
 987         * reasons including that different results are returned on
 988         * different architectures.  It isn't critical that we get exactly
 989         * the same return value as before (we always csum_fold before
 990         * testing, and that removes any differences).  However as we
 991         * know that csum_partial always returned a 16bit value on
 992         * alphas, do a fold to maximise conformity to previous behaviour.
 993         */
 994        sb->sb_csum = md_csum_fold(disk_csum);
 995#else
 996        sb->sb_csum = disk_csum;
 997#endif
 998        return csum;
 999}
1000
1001
1002/*
1003 * Handle superblock details.
1004 * We want to be able to handle multiple superblock formats
1005 * so we have a common interface to them all, and an array of
1006 * different handlers.
1007 * We rely on user-space to write the initial superblock, and support
1008 * reading and updating of superblocks.
1009 * Interface methods are:
1010 *   int load_super(struct md_rdev *dev, struct md_rdev *refdev, int minor_version)
1011 *      loads and validates a superblock on dev.
1012 *      if refdev != NULL, compare superblocks on both devices
1013 *    Return:
1014 *      0 - dev has a superblock that is compatible with refdev
1015 *      1 - dev has a superblock that is compatible and newer than refdev
1016 *          so dev should be used as the refdev in future
1017 *     -EINVAL superblock incompatible or invalid
1018 *     -othererror e.g. -EIO
1019 *
1020 *   int validate_super(struct mddev *mddev, struct md_rdev *dev)
1021 *      Verify that dev is acceptable into mddev.
1022 *       The first time, mddev->raid_disks will be 0, and data from
1023 *       dev should be merged in.  Subsequent calls check that dev
1024 *       is new enough.  Return 0 or -EINVAL
1025 *
1026 *   void sync_super(struct mddev *mddev, struct md_rdev *dev)
1027 *     Update the superblock for rdev with data in mddev
1028 *     This does not write to disc.
1029 *
1030 */
1031
1032struct super_type  {
1033        char                *name;
1034        struct module       *owner;
1035        int                 (*load_super)(struct md_rdev *rdev, struct md_rdev *refdev,
1036                                          int minor_version);
1037        int                 (*validate_super)(struct mddev *mddev, struct md_rdev *rdev);
1038        void                (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
1039        unsigned long long  (*rdev_size_change)(struct md_rdev *rdev,
1040                                                sector_t num_sectors);
1041};
1042
1043/*
1044 * Check that the given mddev has no bitmap.
1045 *
1046 * This function is called from the run method of all personalities that do not
1047 * support bitmaps. It prints an error message and returns non-zero if mddev
1048 * has a bitmap. Otherwise, it returns 0.
1049 *
1050 */
1051int md_check_no_bitmap(struct mddev *mddev)
1052{
1053        if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
1054                return 0;
1055        printk(KERN_ERR "%s: bitmaps are not supported for %s\n",
1056                mdname(mddev), mddev->pers->name);
1057        return 1;
1058}
1059EXPORT_SYMBOL(md_check_no_bitmap);
1060
1061/*
1062 * load_super for 0.90.0 
1063 */
1064static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1065{
1066        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1067        mdp_super_t *sb;
1068        int ret;
1069
1070        /*
1071         * Calculate the position of the superblock (512byte sectors),
1072         * it's at the end of the disk.
1073         *
1074         * It also happens to be a multiple of 4Kb.
1075         */
1076        rdev->sb_start = calc_dev_sboffset(rdev);
1077
1078        ret = read_disk_sb(rdev, MD_SB_BYTES);
1079        if (ret) return ret;
1080
1081        ret = -EINVAL;
1082
1083        bdevname(rdev->bdev, b);
1084        sb = page_address(rdev->sb_page);
1085
1086        if (sb->md_magic != MD_SB_MAGIC) {
1087                printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
1088                       b);
1089                goto abort;
1090        }
1091
1092        if (sb->major_version != 0 ||
1093            sb->minor_version < 90 ||
1094            sb->minor_version > 91) {
1095                printk(KERN_WARNING "Bad version number %d.%d on %s\n",
1096                        sb->major_version, sb->minor_version,
1097                        b);
1098                goto abort;
1099        }
1100
1101        if (sb->raid_disks <= 0)
1102                goto abort;
1103
1104        if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
1105                printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
1106                        b);
1107                goto abort;
1108        }
1109
1110        rdev->preferred_minor = sb->md_minor;
1111        rdev->data_offset = 0;
1112        rdev->sb_size = MD_SB_BYTES;
1113        rdev->badblocks.shift = -1;
1114
1115        if (sb->level == LEVEL_MULTIPATH)
1116                rdev->desc_nr = -1;
1117        else
1118                rdev->desc_nr = sb->this_disk.number;
1119
1120        if (!refdev) {
1121                ret = 1;
1122        } else {
1123                __u64 ev1, ev2;
1124                mdp_super_t *refsb = page_address(refdev->sb_page);
1125                if (!uuid_equal(refsb, sb)) {
1126                        printk(KERN_WARNING "md: %s has different UUID to %s\n",
1127                                b, bdevname(refdev->bdev,b2));
1128                        goto abort;
1129                }
1130                if (!sb_equal(refsb, sb)) {
1131                        printk(KERN_WARNING "md: %s has same UUID"
1132                               " but different superblock to %s\n",
1133                               b, bdevname(refdev->bdev, b2));
1134                        goto abort;
1135                }
1136                ev1 = md_event(sb);
1137                ev2 = md_event(refsb);
1138                if (ev1 > ev2)
1139                        ret = 1;
1140                else 
1141                        ret = 0;
1142        }
1143        rdev->sectors = rdev->sb_start;
1144        /* Limit to 4TB as metadata cannot record more than that */
1145        if (rdev->sectors >= (2ULL << 32))
1146                rdev->sectors = (2ULL << 32) - 2;
1147
1148        if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
1149                /* "this cannot possibly happen" ... */
1150                ret = -EINVAL;
1151
1152 abort:
1153        return ret;
1154}
1155
1156/*
1157 * validate_super for 0.90.0
1158 */
1159static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
1160{
1161        mdp_disk_t *desc;
1162        mdp_super_t *sb = page_address(rdev->sb_page);
1163        __u64 ev1 = md_event(sb);
1164
1165        rdev->raid_disk = -1;
1166        clear_bit(Faulty, &rdev->flags);
1167        clear_bit(In_sync, &rdev->flags);
1168        clear_bit(WriteMostly, &rdev->flags);
1169
1170        if (mddev->raid_disks == 0) {
1171                mddev->major_version = 0;
1172                mddev->minor_version = sb->minor_version;
1173                mddev->patch_version = sb->patch_version;
1174                mddev->external = 0;
1175                mddev->chunk_sectors = sb->chunk_size >> 9;
1176                mddev->ctime = sb->ctime;
1177                mddev->utime = sb->utime;
1178                mddev->level = sb->level;
1179                mddev->clevel[0] = 0;
1180                mddev->layout = sb->layout;
1181                mddev->raid_disks = sb->raid_disks;
1182                mddev->dev_sectors = ((sector_t)sb->size) * 2;
1183                mddev->events = ev1;
1184                mddev->bitmap_info.offset = 0;
1185                mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
1186
1187                if (mddev->minor_version >= 91) {
1188                        mddev->reshape_position = sb->reshape_position;
1189                        mddev->delta_disks = sb->delta_disks;
1190                        mddev->new_level = sb->new_level;
1191                        mddev->new_layout = sb->new_layout;
1192                        mddev->new_chunk_sectors = sb->new_chunk >> 9;
1193                } else {
1194                        mddev->reshape_position = MaxSector;
1195                        mddev->delta_disks = 0;
1196                        mddev->new_level = mddev->level;
1197                        mddev->new_layout = mddev->layout;
1198                        mddev->new_chunk_sectors = mddev->chunk_sectors;
1199                }
1200
1201                if (sb->state & (1<<MD_SB_CLEAN))
1202                        mddev->recovery_cp = MaxSector;
1203                else {
1204                        if (sb->events_hi == sb->cp_events_hi && 
1205                                sb->events_lo == sb->cp_events_lo) {
1206                                mddev->recovery_cp = sb->recovery_cp;
1207                        } else
1208                                mddev->recovery_cp = 0;
1209                }
1210
1211                memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
1212                memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
1213                memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
1214                memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
1215
1216                mddev->max_disks = MD_SB_DISKS;
1217
1218                if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
1219                    mddev->bitmap_info.file == NULL)
1220                        mddev->bitmap_info.offset =
1221                                mddev->bitmap_info.default_offset;
1222
1223        } else if (mddev->pers == NULL) {
1224                /* Insist on good event counter while assembling, except
1225                 * for spares (which don't need an event count) */
1226                ++ev1;
1227                if (sb->disks[rdev->desc_nr].state & (
1228                            (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1229                        if (ev1 < mddev->events) 
1230                                return -EINVAL;
1231        } else if (mddev->bitmap) {
1232                /* if adding to array with a bitmap, then we can accept an
1233                 * older device ... but not too old.
1234                 */
1235                if (ev1 < mddev->bitmap->events_cleared)
1236                        return 0;
1237        } else {
1238                if (ev1 < mddev->events)
1239                        /* just a hot-add of a new device, leave raid_disk at -1 */
1240                        return 0;
1241        }
1242
1243        if (mddev->level != LEVEL_MULTIPATH) {
1244                desc = sb->disks + rdev->desc_nr;
1245
1246                if (desc->state & (1<<MD_DISK_FAULTY))
1247                        set_bit(Faulty, &rdev->flags);
1248                else if (desc->state & (1<<MD_DISK_SYNC) /* &&
1249                            desc->raid_disk < mddev->raid_disks */) {
1250                        set_bit(In_sync, &rdev->flags);
1251                        rdev->raid_disk = desc->raid_disk;
1252                } else if (desc->state & (1<<MD_DISK_ACTIVE)) {
1253                        /* active but not in sync implies recovery up to
1254                         * reshape position.  We don't know exactly where
1255                         * that is, so set to zero for now */
1256                        if (mddev->minor_version >= 91) {
1257                                rdev->recovery_offset = 0;
1258                                rdev->raid_disk = desc->raid_disk;
1259                        }
1260                }
1261                if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
1262                        set_bit(WriteMostly, &rdev->flags);
1263        } else /* MULTIPATH are always insync */
1264                set_bit(In_sync, &rdev->flags);
1265        return 0;
1266}
1267
1268/*
1269 * sync_super for 0.90.0
1270 */
1271static void super_90_sync(struct mddev *mddev, struct md_rdev *rdev)
1272{
1273        mdp_super_t *sb;
1274        struct md_rdev *rdev2;
1275        int next_spare = mddev->raid_disks;
1276
1277
1278        /* make rdev->sb match mddev data..
1279         *
1280         * 1/ zero out disks
1281         * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
1282         * 3/ any empty disks < next_spare become removed
1283         *
1284         * disks[0] gets initialised to REMOVED because
1285         * we cannot be sure from other fields if it has
1286         * been initialised or not.
1287         */
1288        int i;
1289        int active=0, working=0,failed=0,spare=0,nr_disks=0;
1290
1291        rdev->sb_size = MD_SB_BYTES;
1292
1293        sb = page_address(rdev->sb_page);
1294
1295        memset(sb, 0, sizeof(*sb));
1296
1297        sb->md_magic = MD_SB_MAGIC;
1298        sb->major_version = mddev->major_version;
1299        sb->patch_version = mddev->patch_version;
1300        sb->gvalid_words  = 0; /* ignored */
1301        memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
1302        memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
1303        memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
1304        memcpy(&sb->set_uuid3, mddev->uuid+12,4);
1305
1306        sb->ctime = mddev->ctime;
1307        sb->level = mddev->level;
1308        sb->size = mddev->dev_sectors / 2;
1309        sb->raid_disks = mddev->raid_disks;
1310        sb->md_minor = mddev->md_minor;
1311        sb->not_persistent = 0;
1312        sb->utime = mddev->utime;
1313        sb->state = 0;
1314        sb->events_hi = (mddev->events>>32);
1315        sb->events_lo = (u32)mddev->events;
1316
1317        if (mddev->reshape_position == MaxSector)
1318                sb->minor_version = 90;
1319        else {
1320                sb->minor_version = 91;
1321                sb->reshape_position = mddev->reshape_position;
1322                sb->new_level = mddev->new_level;
1323                sb->delta_disks = mddev->delta_disks;
1324                sb->new_layout = mddev->new_layout;
1325                sb->new_chunk = mddev->new_chunk_sectors << 9;
1326        }
1327        mddev->minor_version = sb->minor_version;
1328        if (mddev->in_sync)
1329        {
1330                sb->recovery_cp = mddev->recovery_cp;
1331                sb->cp_events_hi = (mddev->events>>32);
1332                sb->cp_events_lo = (u32)mddev->events;
1333                if (mddev->recovery_cp == MaxSector)
1334                        sb->state = (1<< MD_SB_CLEAN);
1335        } else
1336                sb->recovery_cp = 0;
1337
1338        sb->layout = mddev->layout;
1339        sb->chunk_size = mddev->chunk_sectors << 9;
1340
1341        if (mddev->bitmap && mddev->bitmap_info.file == NULL)
1342                sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1343
1344        sb->disks[0].state = (1<<MD_DISK_REMOVED);
1345        list_for_each_entry(rdev2, &mddev->disks, same_set) {
1346                mdp_disk_t *d;
1347                int desc_nr;
1348                int is_active = test_bit(In_sync, &rdev2->flags);
1349
1350                if (rdev2->raid_disk >= 0 &&
1351                    sb->minor_version >= 91)
1352                        /* we have nowhere to store the recovery_offset,
1353                         * but if it is not below the reshape_position,
1354                         * we can piggy-back on that.
1355                         */
1356                        is_active = 1;
1357                if (rdev2->raid_disk < 0 ||
1358                    test_bit(Faulty, &rdev2->flags))
1359                        is_active = 0;
1360                if (is_active)
1361                        desc_nr = rdev2->raid_disk;
1362                else
1363                        desc_nr = next_spare++;
1364                rdev2->desc_nr = desc_nr;
1365                d = &sb->disks[rdev2->desc_nr];
1366                nr_disks++;
1367                d->number = rdev2->desc_nr;
1368                d->major = MAJOR(rdev2->bdev->bd_dev);
1369                d->minor = MINOR(rdev2->bdev->bd_dev);
1370                if (is_active)
1371                        d->raid_disk = rdev2->raid_disk;
1372                else
1373                        d->raid_disk = rdev2->desc_nr; /* compatibility */
1374                if (test_bit(Faulty, &rdev2->flags))
1375                        d->state = (1<<MD_DISK_FAULTY);
1376                else if (is_active) {
1377                        d->state = (1<<MD_DISK_ACTIVE);
1378                        if (test_bit(In_sync, &rdev2->flags))
1379                                d->state |= (1<<MD_DISK_SYNC);
1380                        active++;
1381                        working++;
1382                } else {
1383                        d->state = 0;
1384                        spare++;
1385                        working++;
1386                }
1387                if (test_bit(WriteMostly, &rdev2->flags))
1388                        d->state |= (1<<MD_DISK_WRITEMOSTLY);
1389        }
1390        /* now set the "removed" and "faulty" bits on any missing devices */
1391        for (i=0 ; i < mddev->raid_disks ; i++) {
1392                mdp_disk_t *d = &sb->disks[i];
1393                if (d->state == 0 && d->number == 0) {
1394                        d->number = i;
1395                        d->raid_disk = i;
1396                        d->state = (1<<MD_DISK_REMOVED);
1397                        d->state |= (1<<MD_DISK_FAULTY);
1398                        failed++;
1399                }
1400        }
1401        sb->nr_disks = nr_disks;
1402        sb->active_disks = active;
1403        sb->working_disks = working;
1404        sb->failed_disks = failed;
1405        sb->spare_disks = spare;
1406
1407        sb->this_disk = sb->disks[rdev->desc_nr];
1408        sb->sb_csum = calc_sb_csum(sb);
1409}
1410
1411/*
1412 * rdev_size_change for 0.90.0
1413 */
1414static unsigned long long
1415super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1416{
1417        if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1418                return 0; /* component must fit device */
1419        if (rdev->mddev->bitmap_info.offset)
1420                return 0; /* can't move bitmap */
1421        rdev->sb_start = calc_dev_sboffset(rdev);
1422        if (!num_sectors || num_sectors > rdev->sb_start)
1423                num_sectors = rdev->sb_start;
1424        /* Limit to 4TB as metadata cannot record more than that.
1425         * 4TB == 2^32 KB, or 2*2^32 sectors.
1426         */
1427        if (num_sectors >= (2ULL << 32))
1428                num_sectors = (2ULL << 32) - 2;
1429        md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1430                       rdev->sb_page);
1431        md_super_wait(rdev->mddev);
1432        return num_sectors;
1433}
1434
1435
1436/*
1437 * version 1 superblock
1438 */
1439
1440static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
1441{
1442        __le32 disk_csum;
1443        u32 csum;
1444        unsigned long long newcsum;
1445        int size = 256 + le32_to_cpu(sb->max_dev)*2;
1446        __le32 *isuper = (__le32*)sb;
1447        int i;
1448
1449        disk_csum = sb->sb_csum;
1450        sb->sb_csum = 0;
1451        newcsum = 0;
1452        for (i=0; size>=4; size -= 4 )
1453                newcsum += le32_to_cpu(*isuper++);
1454
1455        if (size == 2)
1456                newcsum += le16_to_cpu(*(__le16*) isuper);
1457
1458        csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1459        sb->sb_csum = disk_csum;
1460        return cpu_to_le32(csum);
1461}
1462
1463static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
1464                            int acknowledged);
1465static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1466{
1467        struct mdp_superblock_1 *sb;
1468        int ret;
1469        sector_t sb_start;
1470        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1471        int bmask;
1472
1473        /*
1474         * Calculate the position of the superblock in 512byte sectors.
1475         * It is always aligned to a 4K boundary and
1476         * depeding on minor_version, it can be:
1477         * 0: At least 8K, but less than 12K, from end of device
1478         * 1: At start of device
1479         * 2: 4K from start of device.
1480         */
1481        switch(minor_version) {
1482        case 0:
1483                sb_start = i_size_read(rdev->bdev->bd_inode) >> 9;
1484                sb_start -= 8*2;
1485                sb_start &= ~(sector_t)(4*2-1);
1486                break;
1487        case 1:
1488                sb_start = 0;
1489                break;
1490        case 2:
1491                sb_start = 8;
1492                break;
1493        default:
1494                return -EINVAL;
1495        }
1496        rdev->sb_start = sb_start;
1497
1498        /* superblock is rarely larger than 1K, but it can be larger,
1499         * and it is safe to read 4k, so we do that
1500         */
1501        ret = read_disk_sb(rdev, 4096);
1502        if (ret) return ret;
1503
1504
1505        sb = page_address(rdev->sb_page);
1506
1507        if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1508            sb->major_version != cpu_to_le32(1) ||
1509            le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1510            le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1511            (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1512                return -EINVAL;
1513
1514        if (calc_sb_1_csum(sb) != sb->sb_csum) {
1515                printk("md: invalid superblock checksum on %s\n",
1516                        bdevname(rdev->bdev,b));
1517                return -EINVAL;
1518        }
1519        if (le64_to_cpu(sb->data_size) < 10) {
1520                printk("md: data_size too small on %s\n",
1521                       bdevname(rdev->bdev,b));
1522                return -EINVAL;
1523        }
1524
1525        rdev->preferred_minor = 0xffff;
1526        rdev->data_offset = le64_to_cpu(sb->data_offset);
1527        atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1528
1529        rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1530        bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1531        if (rdev->sb_size & bmask)
1532                rdev->sb_size = (rdev->sb_size | bmask) + 1;
1533
1534        if (minor_version
1535            && rdev->data_offset < sb_start + (rdev->sb_size/512))
1536                return -EINVAL;
1537
1538        if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1539                rdev->desc_nr = -1;
1540        else
1541                rdev->desc_nr = le32_to_cpu(sb->dev_number);
1542
1543        if (!rdev->bb_page) {
1544                rdev->bb_page = alloc_page(GFP_KERNEL);
1545                if (!rdev->bb_page)
1546                        return -ENOMEM;
1547        }
1548        if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
1549            rdev->badblocks.count == 0) {
1550                /* need to load the bad block list.
1551                 * Currently we limit it to one page.
1552                 */
1553                s32 offset;
1554                sector_t bb_sector;
1555                u64 *bbp;
1556                int i;
1557                int sectors = le16_to_cpu(sb->bblog_size);
1558                if (sectors > (PAGE_SIZE / 512))
1559                        return -EINVAL;
1560                offset = le32_to_cpu(sb->bblog_offset);
1561                if (offset == 0)
1562                        return -EINVAL;
1563                bb_sector = (long long)offset;
1564                if (!sync_page_io(rdev, bb_sector, sectors << 9,
1565                                  rdev->bb_page, READ, true))
1566                        return -EIO;
1567                bbp = (u64 *)page_address(rdev->bb_page);
1568                rdev->badblocks.shift = sb->bblog_shift;
1569                for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1570                        u64 bb = le64_to_cpu(*bbp);
1571                        int count = bb & (0x3ff);
1572                        u64 sector = bb >> 10;
1573                        sector <<= sb->bblog_shift;
1574                        count <<= sb->bblog_shift;
1575                        if (bb + 1 == 0)
1576                                break;
1577                        if (md_set_badblocks(&rdev->badblocks,
1578                                             sector, count, 1) == 0)
1579                                return -EINVAL;
1580                }
1581        } else if (sb->bblog_offset == 0)
1582                rdev->badblocks.shift = -1;
1583
1584        if (!refdev) {
1585                ret = 1;
1586        } else {
1587                __u64 ev1, ev2;
1588                struct mdp_superblock_1 *refsb = page_address(refdev->sb_page);
1589
1590                if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1591                    sb->level != refsb->level ||
1592                    sb->layout != refsb->layout ||
1593                    sb->chunksize != refsb->chunksize) {
1594                        printk(KERN_WARNING "md: %s has strangely different"
1595                                " superblock to %s\n",
1596                                bdevname(rdev->bdev,b),
1597                                bdevname(refdev->bdev,b2));
1598                        return -EINVAL;
1599                }
1600                ev1 = le64_to_cpu(sb->events);
1601                ev2 = le64_to_cpu(refsb->events);
1602
1603                if (ev1 > ev2)
1604                        ret = 1;
1605                else
1606                        ret = 0;
1607        }
1608        if (minor_version)
1609                rdev->sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
1610                        le64_to_cpu(sb->data_offset);
1611        else
1612                rdev->sectors = rdev->sb_start;
1613        if (rdev->sectors < le64_to_cpu(sb->data_size))
1614                return -EINVAL;
1615        rdev->sectors = le64_to_cpu(sb->data_size);
1616        if (le64_to_cpu(sb->size) > rdev->sectors)
1617                return -EINVAL;
1618        return ret;
1619}
1620
1621static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
1622{
1623        struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1624        __u64 ev1 = le64_to_cpu(sb->events);
1625
1626        rdev->raid_disk = -1;
1627        clear_bit(Faulty, &rdev->flags);
1628        clear_bit(In_sync, &rdev->flags);
1629        clear_bit(WriteMostly, &rdev->flags);
1630
1631        if (mddev->raid_disks == 0) {
1632                mddev->major_version = 1;
1633                mddev->patch_version = 0;
1634                mddev->external = 0;
1635                mddev->chunk_sectors = le32_to_cpu(sb->chunksize);
1636                mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
1637                mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
1638                mddev->level = le32_to_cpu(sb->level);
1639                mddev->clevel[0] = 0;
1640                mddev->layout = le32_to_cpu(sb->layout);
1641                mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1642                mddev->dev_sectors = le64_to_cpu(sb->size);
1643                mddev->events = ev1;
1644                mddev->bitmap_info.offset = 0;
1645                mddev->bitmap_info.default_offset = 1024 >> 9;
1646                
1647                mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1648                memcpy(mddev->uuid, sb->set_uuid, 16);
1649
1650                mddev->max_disks =  (4096-256)/2;
1651
1652                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1653                    mddev->bitmap_info.file == NULL )
1654                        mddev->bitmap_info.offset =
1655                                (__s32)le32_to_cpu(sb->bitmap_offset);
1656
1657                if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1658                        mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1659                        mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1660                        mddev->new_level = le32_to_cpu(sb->new_level);
1661                        mddev->new_layout = le32_to_cpu(sb->new_layout);
1662                        mddev->new_chunk_sectors = le32_to_cpu(sb->new_chunk);
1663                } else {
1664                        mddev->reshape_position = MaxSector;
1665                        mddev->delta_disks = 0;
1666                        mddev->new_level = mddev->level;
1667                        mddev->new_layout = mddev->layout;
1668                        mddev->new_chunk_sectors = mddev->chunk_sectors;
1669                }
1670
1671        } else if (mddev->pers == NULL) {
1672                /* Insist of good event counter while assembling, except for
1673                 * spares (which don't need an event count) */
1674                ++ev1;
1675                if (rdev->desc_nr >= 0 &&
1676                    rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1677                    le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < 0xfffe)
1678                        if (ev1 < mddev->events)
1679                                return -EINVAL;
1680        } else if (mddev->bitmap) {
1681                /* If adding to array with a bitmap, then we can accept an
1682                 * older device, but not too old.
1683                 */
1684                if (ev1 < mddev->bitmap->events_cleared)
1685                        return 0;
1686        } else {
1687                if (ev1 < mddev->events)
1688                        /* just a hot-add of a new device, leave raid_disk at -1 */
1689                        return 0;
1690        }
1691        if (mddev->level != LEVEL_MULTIPATH) {
1692                int role;
1693                if (rdev->desc_nr < 0 ||
1694                    rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
1695                        role = 0xffff;
1696                        rdev->desc_nr = -1;
1697                } else
1698                        role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1699                switch(role) {
1700                case 0xffff: /* spare */
1701                        break;
1702                case 0xfffe: /* faulty */
1703                        set_bit(Faulty, &rdev->flags);
1704                        break;
1705                default:
1706                        if ((le32_to_cpu(sb->feature_map) &
1707                             MD_FEATURE_RECOVERY_OFFSET))
1708                                rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1709                        else
1710                                set_bit(In_sync, &rdev->flags);
1711                        rdev->raid_disk = role;
1712                        break;
1713                }
1714                if (sb->devflags & WriteMostly1)
1715                        set_bit(WriteMostly, &rdev->flags);
1716                if (le32_to_cpu(sb->feature_map) & MD_FEATURE_REPLACEMENT)
1717                        set_bit(Replacement, &rdev->flags);
1718        } else /* MULTIPATH are always insync */
1719                set_bit(In_sync, &rdev->flags);
1720
1721        return 0;
1722}
1723
1724static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
1725{
1726        struct mdp_superblock_1 *sb;
1727        struct md_rdev *rdev2;
1728        int max_dev, i;
1729        /* make rdev->sb match mddev and rdev data. */
1730
1731        sb = page_address(rdev->sb_page);
1732
1733        sb->feature_map = 0;
1734        sb->pad0 = 0;
1735        sb->recovery_offset = cpu_to_le64(0);
1736        memset(sb->pad1, 0, sizeof(sb->pad1));
1737        memset(sb->pad3, 0, sizeof(sb->pad3));
1738
1739        sb->utime = cpu_to_le64((__u64)mddev->utime);
1740        sb->events = cpu_to_le64(mddev->events);
1741        if (mddev->in_sync)
1742                sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1743        else
1744                sb->resync_offset = cpu_to_le64(0);
1745
1746        sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1747
1748        sb->raid_disks = cpu_to_le32(mddev->raid_disks);
1749        sb->size = cpu_to_le64(mddev->dev_sectors);
1750        sb->chunksize = cpu_to_le32(mddev->chunk_sectors);
1751        sb->level = cpu_to_le32(mddev->level);
1752        sb->layout = cpu_to_le32(mddev->layout);
1753
1754        if (test_bit(WriteMostly, &rdev->flags))
1755                sb->devflags |= WriteMostly1;
1756        else
1757                sb->devflags &= ~WriteMostly1;
1758
1759        if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
1760                sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
1761                sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
1762        }
1763
1764        if (rdev->raid_disk >= 0 &&
1765            !test_bit(In_sync, &rdev->flags)) {
1766                sb->feature_map |=
1767                        cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
1768                sb->recovery_offset =
1769                        cpu_to_le64(rdev->recovery_offset);
1770        }
1771        if (test_bit(Replacement, &rdev->flags))
1772                sb->feature_map |=
1773                        cpu_to_le32(MD_FEATURE_REPLACEMENT);
1774
1775        if (mddev->reshape_position != MaxSector) {
1776                sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
1777                sb->reshape_position = cpu_to_le64(mddev->reshape_position);
1778                sb->new_layout = cpu_to_le32(mddev->new_layout);
1779                sb->delta_disks = cpu_to_le32(mddev->delta_disks);
1780                sb->new_level = cpu_to_le32(mddev->new_level);
1781                sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
1782        }
1783
1784        if (rdev->badblocks.count == 0)
1785                /* Nothing to do for bad blocks*/ ;
1786        else if (sb->bblog_offset == 0)
1787                /* Cannot record bad blocks on this device */
1788                md_error(mddev, rdev);
1789        else {
1790                struct badblocks *bb = &rdev->badblocks;
1791                u64 *bbp = (u64 *)page_address(rdev->bb_page);
1792                u64 *p = bb->page;
1793                sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
1794                if (bb->changed) {
1795                        unsigned seq;
1796
1797retry:
1798                        seq = read_seqbegin(&bb->lock);
1799
1800                        memset(bbp, 0xff, PAGE_SIZE);
1801
1802                        for (i = 0 ; i < bb->count ; i++) {
1803                                u64 internal_bb = *p++;
1804                                u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
1805                                                | BB_LEN(internal_bb));
1806                                *bbp++ = cpu_to_le64(store_bb);
1807                        }
1808                        if (read_seqretry(&bb->lock, seq))
1809                                goto retry;
1810
1811                        bb->sector = (rdev->sb_start +
1812                                      (int)le32_to_cpu(sb->bblog_offset));
1813                        bb->size = le16_to_cpu(sb->bblog_size);
1814                        bb->changed = 0;
1815                }
1816        }
1817
1818        max_dev = 0;
1819        list_for_each_entry(rdev2, &mddev->disks, same_set)
1820                if (rdev2->desc_nr+1 > max_dev)
1821                        max_dev = rdev2->desc_nr+1;
1822
1823        if (max_dev > le32_to_cpu(sb->max_dev)) {
1824                int bmask;
1825                sb->max_dev = cpu_to_le32(max_dev);
1826                rdev->sb_size = max_dev * 2 + 256;
1827                bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1828                if (rdev->sb_size & bmask)
1829                        rdev->sb_size = (rdev->sb_size | bmask) + 1;
1830        } else
1831                max_dev = le32_to_cpu(sb->max_dev);
1832
1833        for (i=0; i<max_dev;i++)
1834                sb->dev_roles[i] = cpu_to_le16(0xfffe);
1835        
1836        list_for_each_entry(rdev2, &mddev->disks, same_set) {
1837                i = rdev2->desc_nr;
1838                if (test_bit(Faulty, &rdev2->flags))
1839                        sb->dev_roles[i] = cpu_to_le16(0xfffe);
1840                else if (test_bit(In_sync, &rdev2->flags))
1841                        sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1842                else if (rdev2->raid_disk >= 0)
1843                        sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
1844                else
1845                        sb->dev_roles[i] = cpu_to_le16(0xffff);
1846        }
1847
1848        sb->sb_csum = calc_sb_1_csum(sb);
1849}
1850
1851static unsigned long long
1852super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1853{
1854        struct mdp_superblock_1 *sb;
1855        sector_t max_sectors;
1856        if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1857                return 0; /* component must fit device */
1858        if (rdev->sb_start < rdev->data_offset) {
1859                /* minor versions 1 and 2; superblock before data */
1860                max_sectors = i_size_read(rdev->bdev->bd_inode) >> 9;
1861                max_sectors -= rdev->data_offset;
1862                if (!num_sectors || num_sectors > max_sectors)
1863                        num_sectors = max_sectors;
1864        } else if (rdev->mddev->bitmap_info.offset) {
1865                /* minor version 0 with bitmap we can't move */
1866                return 0;
1867        } else {
1868                /* minor version 0; superblock after data */
1869                sector_t sb_start;
1870                sb_start = (i_size_read(rdev->bdev->bd_inode) >> 9) - 8*2;
1871                sb_start &= ~(sector_t)(4*2 - 1);
1872                max_sectors = rdev->sectors + sb_start - rdev->sb_start;
1873                if (!num_sectors || num_sectors > max_sectors)
1874                        num_sectors = max_sectors;
1875                rdev->sb_start = sb_start;
1876        }
1877        sb = page_address(rdev->sb_page);
1878        sb->data_size = cpu_to_le64(num_sectors);
1879        sb->super_offset = rdev->sb_start;
1880        sb->sb_csum = calc_sb_1_csum(sb);
1881        md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1882                       rdev->sb_page);
1883        md_super_wait(rdev->mddev);
1884        return num_sectors;
1885}
1886
1887static struct super_type super_types[] = {
1888        [0] = {
1889                .name   = "0.90.0",
1890                .owner  = THIS_MODULE,
1891                .load_super         = super_90_load,
1892                .validate_super     = super_90_validate,
1893                .sync_super         = super_90_sync,
1894                .rdev_size_change   = super_90_rdev_size_change,
1895        },
1896        [1] = {
1897                .name   = "md-1",
1898                .owner  = THIS_MODULE,
1899                .load_super         = super_1_load,
1900                .validate_super     = super_1_validate,
1901                .sync_super         = super_1_sync,
1902                .rdev_size_change   = super_1_rdev_size_change,
1903        },
1904};
1905
1906static void sync_super(struct mddev *mddev, struct md_rdev *rdev)
1907{
1908        if (mddev->sync_super) {
1909                mddev->sync_super(mddev, rdev);
1910                return;
1911        }
1912
1913        BUG_ON(mddev->major_version >= ARRAY_SIZE(super_types));
1914
1915        super_types[mddev->major_version].sync_super(mddev, rdev);
1916}
1917
1918static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
1919{
1920        struct md_rdev *rdev, *rdev2;
1921
1922        rcu_read_lock();
1923        rdev_for_each_rcu(rdev, mddev1)
1924                rdev_for_each_rcu(rdev2, mddev2)
1925                        if (rdev->bdev->bd_contains ==
1926                            rdev2->bdev->bd_contains) {
1927                                rcu_read_unlock();
1928                                return 1;
1929                        }
1930        rcu_read_unlock();
1931        return 0;
1932}
1933
1934static LIST_HEAD(pending_raid_disks);
1935
1936/*
1937 * Try to register data integrity profile for an mddev
1938 *
1939 * This is called when an array is started and after a disk has been kicked
1940 * from the array. It only succeeds if all working and active component devices
1941 * are integrity capable with matching profiles.
1942 */
1943int md_integrity_register(struct mddev *mddev)
1944{
1945        struct md_rdev *rdev, *reference = NULL;
1946
1947        if (list_empty(&mddev->disks))
1948                return 0; /* nothing to do */
1949        if (!mddev->gendisk || blk_get_integrity(mddev->gendisk))
1950                return 0; /* shouldn't register, or already is */
1951        list_for_each_entry(rdev, &mddev->disks, same_set) {
1952                /* skip spares and non-functional disks */
1953                if (test_bit(Faulty, &rdev->flags))
1954                        continue;
1955                if (rdev->raid_disk < 0)
1956                        continue;
1957                if (!reference) {
1958                        /* Use the first rdev as the reference */
1959                        reference = rdev;
1960                        continue;
1961                }
1962                /* does this rdev's profile match the reference profile? */
1963                if (blk_integrity_compare(reference->bdev->bd_disk,
1964                                rdev->bdev->bd_disk) < 0)
1965                        return -EINVAL;
1966        }
1967        if (!reference || !bdev_get_integrity(reference->bdev))
1968                return 0;
1969        /*
1970         * All component devices are integrity capable and have matching
1971         * profiles, register the common profile for the md device.
1972         */
1973        if (blk_integrity_register(mddev->gendisk,
1974                        bdev_get_integrity(reference->bdev)) != 0) {
1975                printk(KERN_ERR "md: failed to register integrity for %s\n",
1976                        mdname(mddev));
1977                return -EINVAL;
1978        }
1979        printk(KERN_NOTICE "md: data integrity enabled on %s\n", mdname(mddev));
1980        if (bioset_integrity_create(mddev->bio_set, BIO_POOL_SIZE)) {
1981                printk(KERN_ERR "md: failed to create integrity pool for %s\n",
1982                       mdname(mddev));
1983                return -EINVAL;
1984        }
1985        return 0;
1986}
1987EXPORT_SYMBOL(md_integrity_register);
1988
1989/* Disable data integrity if non-capable/non-matching disk is being added */
1990void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
1991{
1992        struct blk_integrity *bi_rdev = bdev_get_integrity(rdev->bdev);
1993        struct blk_integrity *bi_mddev = blk_get_integrity(mddev->gendisk);
1994
1995        if (!bi_mddev) /* nothing to do */
1996                return;
1997        if (rdev->raid_disk < 0) /* skip spares */
1998                return;
1999        if (bi_rdev && blk_integrity_compare(mddev->gendisk,
2000                                             rdev->bdev->bd_disk) >= 0)
2001                return;
2002        printk(KERN_NOTICE "disabling data integrity on %s\n", mdname(mddev));
2003        blk_integrity_unregister(mddev->gendisk);
2004}
2005EXPORT_SYMBOL(md_integrity_add_rdev);
2006
2007static int bind_rdev_to_array(struct md_rdev * rdev, struct mddev * mddev)
2008{
2009        char b[BDEVNAME_SIZE];
2010        struct kobject *ko;
2011        char *s;
2012        int err;
2013
2014        if (rdev->mddev) {
2015                MD_BUG();
2016                return -EINVAL;
2017        }
2018
2019        /* prevent duplicates */
2020        if (find_rdev(mddev, rdev->bdev->bd_dev))
2021                return -EEXIST;
2022
2023        /* make sure rdev->sectors exceeds mddev->dev_sectors */
2024        if (rdev->sectors && (mddev->dev_sectors == 0 ||
2025                        rdev->sectors < mddev->dev_sectors)) {
2026                if (mddev->pers) {
2027                        /* Cannot change size, so fail
2028                         * If mddev->level <= 0, then we don't care
2029                         * about aligning sizes (e.g. linear)
2030                         */
2031                        if (mddev->level > 0)
2032                                return -ENOSPC;
2033                } else
2034                        mddev->dev_sectors = rdev->sectors;
2035        }
2036
2037        /* Verify rdev->desc_nr is unique.
2038         * If it is -1, assign a free number, else
2039         * check number is not in use
2040         */
2041        if (rdev->desc_nr < 0) {
2042                int choice = 0;
2043                if (mddev->pers) choice = mddev->raid_disks;
2044                while (find_rdev_nr(mddev, choice))
2045                        choice++;
2046                rdev->desc_nr = choice;
2047        } else {
2048                if (find_rdev_nr(mddev, rdev->desc_nr))
2049                        return -EBUSY;
2050        }
2051        if (mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
2052                printk(KERN_WARNING "md: %s: array is limited to %d devices\n",
2053                       mdname(mddev), mddev->max_disks);
2054                return -EBUSY;
2055        }
2056        bdevname(rdev->bdev,b);
2057        while ( (s=strchr(b, '/')) != NULL)
2058                *s = '!';
2059
2060        rdev->mddev = mddev;
2061        printk(KERN_INFO "md: bind<%s>\n", b);
2062
2063        if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
2064                goto fail;
2065
2066        ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
2067        if (sysfs_create_link(&rdev->kobj, ko, "block"))
2068                /* failure here is OK */;
2069        rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
2070
2071        list_add_rcu(&rdev->same_set, &mddev->disks);
2072        bd_link_disk_holder(rdev->bdev, mddev->gendisk);
2073
2074        /* May as well allow recovery to be retried once */
2075        mddev->recovery_disabled++;
2076
2077        return 0;
2078
2079 fail:
2080        printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
2081               b, mdname(mddev));
2082        return err;
2083}
2084
2085static void md_delayed_delete(struct work_struct *ws)
2086{
2087        struct md_rdev *rdev = container_of(ws, struct md_rdev, del_work);
2088        kobject_del(&rdev->kobj);
2089        kobject_put(&rdev->kobj);
2090}
2091
2092static void unbind_rdev_from_array(struct md_rdev * rdev)
2093{
2094        char b[BDEVNAME_SIZE];
2095        if (!rdev->mddev) {
2096                MD_BUG();
2097                return;
2098        }
2099        bd_unlink_disk_holder(rdev->bdev, rdev->mddev->gendisk);
2100        list_del_rcu(&rdev->same_set);
2101        printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
2102        rdev->mddev = NULL;
2103        sysfs_remove_link(&rdev->kobj, "block");
2104        sysfs_put(rdev->sysfs_state);
2105        rdev->sysfs_state = NULL;
2106        kfree(rdev->badblocks.page);
2107        rdev->badblocks.count = 0;
2108        rdev->badblocks.page = NULL;
2109        /* We need to delay this, otherwise we can deadlock when
2110         * writing to 'remove' to "dev/state".  We also need
2111         * to delay it due to rcu usage.
2112         */
2113        synchronize_rcu();
2114        INIT_WORK(&rdev->del_work, md_delayed_delete);
2115        kobject_get(&rdev->kobj);
2116        queue_work(md_misc_wq, &rdev->del_work);
2117}
2118
2119/*
2120 * prevent the device from being mounted, repartitioned or
2121 * otherwise reused by a RAID array (or any other kernel
2122 * subsystem), by bd_claiming the device.
2123 */
2124static int lock_rdev(struct md_rdev *rdev, dev_t dev, int shared)
2125{
2126        int err = 0;
2127        struct block_device *bdev;
2128        char b[BDEVNAME_SIZE];
2129
2130        bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
2131                                 shared ? (struct md_rdev *)lock_rdev : rdev);
2132        if (IS_ERR(bdev)) {
2133                printk(KERN_ERR "md: could not open %s.\n",
2134                        __bdevname(dev, b));
2135                return PTR_ERR(bdev);
2136        }
2137        rdev->bdev = bdev;
2138        return err;
2139}
2140
2141static void unlock_rdev(struct md_rdev *rdev)
2142{
2143        struct block_device *bdev = rdev->bdev;
2144        rdev->bdev = NULL;
2145        if (!bdev)
2146                MD_BUG();
2147        blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
2148}
2149
2150void md_autodetect_dev(dev_t dev);
2151
2152static void export_rdev(struct md_rdev * rdev)
2153{
2154        char b[BDEVNAME_SIZE];
2155        printk(KERN_INFO "md: export_rdev(%s)\n",
2156                bdevname(rdev->bdev,b));
2157        if (rdev->mddev)
2158                MD_BUG();
2159        free_disk_sb(rdev);
2160#ifndef MODULE
2161        if (test_bit(AutoDetected, &rdev->flags))
2162                md_autodetect_dev(rdev->bdev->bd_dev);
2163#endif
2164        unlock_rdev(rdev);
2165        kobject_put(&rdev->kobj);
2166}
2167
2168static void kick_rdev_from_array(struct md_rdev * rdev)
2169{
2170        unbind_rdev_from_array(rdev);
2171        export_rdev(rdev);
2172}
2173
2174static void export_array(struct mddev *mddev)
2175{
2176        struct md_rdev *rdev, *tmp;
2177
2178        rdev_for_each(rdev, tmp, mddev) {
2179                if (!rdev->mddev) {
2180                        MD_BUG();
2181                        continue;
2182                }
2183                kick_rdev_from_array(rdev);
2184        }
2185        if (!list_empty(&mddev->disks))
2186                MD_BUG();
2187        mddev->raid_disks = 0;
2188        mddev->major_version = 0;
2189}
2190
2191static void print_desc(mdp_disk_t *desc)
2192{
2193        printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
2194                desc->major,desc->minor,desc->raid_disk,desc->state);
2195}
2196
2197static void print_sb_90(mdp_super_t *sb)
2198{
2199        int i;
2200
2201        printk(KERN_INFO 
2202                "md:  SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
2203                sb->major_version, sb->minor_version, sb->patch_version,
2204                sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
2205                sb->ctime);
2206        printk(KERN_INFO "md:     L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
2207                sb->level, sb->size, sb->nr_disks, sb->raid_disks,
2208                sb->md_minor, sb->layout, sb->chunk_size);
2209        printk(KERN_INFO "md:     UT:%08x ST:%d AD:%d WD:%d"
2210                " FD:%d SD:%d CSUM:%08x E:%08lx\n",
2211                sb->utime, sb->state, sb->active_disks, sb->working_disks,
2212                sb->failed_disks, sb->spare_disks,
2213                sb->sb_csum, (unsigned long)sb->events_lo);
2214
2215        printk(KERN_INFO);
2216        for (i = 0; i < MD_SB_DISKS; i++) {
2217                mdp_disk_t *desc;
2218
2219                desc = sb->disks + i;
2220                if (desc->number || desc->major || desc->minor ||
2221                    desc->raid_disk || (desc->state && (desc->state != 4))) {
2222                        printk("     D %2d: ", i);
2223                        print_desc(desc);
2224                }
2225        }
2226        printk(KERN_INFO "md:     THIS: ");
2227        print_desc(&sb->this_disk);
2228}
2229
2230static void print_sb_1(struct mdp_superblock_1 *sb)
2231{
2232        __u8 *uuid;
2233
2234        uuid = sb->set_uuid;
2235        printk(KERN_INFO
2236               "md:  SB: (V:%u) (F:0x%08x) Array-ID:<%pU>\n"
2237               "md:    Name: \"%s\" CT:%llu\n",
2238                le32_to_cpu(sb->major_version),
2239                le32_to_cpu(sb->feature_map),
2240                uuid,
2241                sb->set_name,
2242                (unsigned long long)le64_to_cpu(sb->ctime)
2243                       & MD_SUPERBLOCK_1_TIME_SEC_MASK);
2244
2245        uuid = sb->device_uuid;
2246        printk(KERN_INFO
2247               "md:       L%u SZ%llu RD:%u LO:%u CS:%u DO:%llu DS:%llu SO:%llu"
2248                        " RO:%llu\n"
2249               "md:     Dev:%08x UUID: %pU\n"
2250               "md:       (F:0x%08x) UT:%llu Events:%llu ResyncOffset:%llu CSUM:0x%08x\n"
2251               "md:         (MaxDev:%u) \n",
2252                le32_to_cpu(sb->level),
2253                (unsigned long long)le64_to_cpu(sb->size),
2254                le32_to_cpu(sb->raid_disks),
2255                le32_to_cpu(sb->layout),
2256                le32_to_cpu(sb->chunksize),
2257                (unsigned long long)le64_to_cpu(sb->data_offset),
2258                (unsigned long long)le64_to_cpu(sb->data_size),
2259                (unsigned long long)le64_to_cpu(sb->super_offset),
2260                (unsigned long long)le64_to_cpu(sb->recovery_offset),
2261                le32_to_cpu(sb->dev_number),
2262                uuid,
2263                sb->devflags,
2264                (unsigned long long)le64_to_cpu(sb->utime) & MD_SUPERBLOCK_1_TIME_SEC_MASK,
2265                (unsigned long long)le64_to_cpu(sb->events),
2266                (unsigned long long)le64_to_cpu(sb->resync_offset),
2267                le32_to_cpu(sb->sb_csum),
2268                le32_to_cpu(sb->max_dev)
2269                );
2270}
2271
2272static void print_rdev(struct md_rdev *rdev, int major_version)
2273{
2274        char b[BDEVNAME_SIZE];
2275        printk(KERN_INFO "md: rdev %s, Sect:%08llu F:%d S:%d DN:%u\n",
2276                bdevname(rdev->bdev, b), (unsigned long long)rdev->sectors,
2277                test_bit(Faulty, &rdev->flags), test_bit(In_sync, &rdev->flags),
2278                rdev->desc_nr);
2279        if (rdev->sb_loaded) {
2280                printk(KERN_INFO "md: rdev superblock (MJ:%d):\n", major_version);
2281                switch (major_version) {
2282                case 0:
2283                        print_sb_90(page_address(rdev->sb_page));
2284                        break;
2285                case 1:
2286                        print_sb_1(page_address(rdev->sb_page));
2287                        break;
2288                }
2289        } else
2290                printk(KERN_INFO "md: no rdev superblock!\n");
2291}
2292
2293static void md_print_devices(void)
2294{
2295        struct list_head *tmp;
2296        struct md_rdev *rdev;
2297        struct mddev *mddev;
2298        char b[BDEVNAME_SIZE];
2299
2300        printk("\n");
2301        printk("md:     **********************************\n");
2302        printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
2303        printk("md:     **********************************\n");
2304        for_each_mddev(mddev, tmp) {
2305
2306                if (mddev->bitmap)
2307                        bitmap_print_sb(mddev->bitmap);
2308                else
2309                        printk("%s: ", mdname(mddev));
2310                list_for_each_entry(rdev, &mddev->disks, same_set)
2311                        printk("<%s>", bdevname(rdev->bdev,b));
2312                printk("\n");
2313
2314                list_for_each_entry(rdev, &mddev->disks, same_set)
2315                        print_rdev(rdev, mddev->major_version);
2316        }
2317        printk("md:     **********************************\n");
2318        printk("\n");
2319}
2320
2321
2322static void sync_sbs(struct mddev * mddev, int nospares)
2323{
2324        /* Update each superblock (in-memory image), but
2325         * if we are allowed to, skip spares which already
2326         * have the right event counter, or have one earlier
2327         * (which would mean they aren't being marked as dirty
2328         * with the rest of the array)
2329         */
2330        struct md_rdev *rdev;
2331        list_for_each_entry(rdev, &mddev->disks, same_set) {
2332                if (rdev->sb_events == mddev->events ||
2333                    (nospares &&
2334                     rdev->raid_disk < 0 &&
2335                     rdev->sb_events+1 == mddev->events)) {
2336                        /* Don't update this superblock */
2337                        rdev->sb_loaded = 2;
2338                } else {
2339                        sync_super(mddev, rdev);
2340                        rdev->sb_loaded = 1;
2341                }
2342        }
2343}
2344
2345static void md_update_sb(struct mddev * mddev, int force_change)
2346{
2347        struct md_rdev *rdev;
2348        int sync_req;
2349        int nospares = 0;
2350        int any_badblocks_changed = 0;
2351
2352repeat:
2353        /* First make sure individual recovery_offsets are correct */
2354        list_for_each_entry(rdev, &mddev->disks, same_set) {
2355                if (rdev->raid_disk >= 0 &&
2356                    mddev->delta_disks >= 0 &&
2357                    !test_bit(In_sync, &rdev->flags) &&
2358                    mddev->curr_resync_completed > rdev->recovery_offset)
2359                                rdev->recovery_offset = mddev->curr_resync_completed;
2360
2361        }       
2362        if (!mddev->persistent) {
2363                clear_bit(MD_CHANGE_CLEAN, &mddev->flags);
2364                clear_bit(MD_CHANGE_DEVS, &mddev->flags);
2365                if (!mddev->external) {
2366                        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2367                        list_for_each_entry(rdev, &mddev->disks, same_set) {
2368                                if (rdev->badblocks.changed) {
2369                                        md_ack_all_badblocks(&rdev->badblocks);
2370                                        md_error(mddev, rdev);
2371                                }
2372                                clear_bit(Blocked, &rdev->flags);
2373                                clear_bit(BlockedBadBlocks, &rdev->flags);
2374                                wake_up(&rdev->blocked_wait);
2375                        }
2376                }
2377                wake_up(&mddev->sb_wait);
2378                return;
2379        }
2380
2381        spin_lock_irq(&mddev->write_lock);
2382
2383        mddev->utime = get_seconds();
2384
2385        if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
2386                force_change = 1;
2387        if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
2388                /* just a clean<-> dirty transition, possibly leave spares alone,
2389                 * though if events isn't the right even/odd, we will have to do
2390                 * spares after all
2391                 */
2392                nospares = 1;
2393        if (force_change)
2394                nospares = 0;
2395        if (mddev->degraded)
2396                /* If the array is degraded, then skipping spares is both
2397                 * dangerous and fairly pointless.
2398                 * Dangerous because a device that was removed from the array
2399                 * might have a event_count that still looks up-to-date,
2400                 * so it can be re-added without a resync.
2401                 * Pointless because if there are any spares to skip,
2402                 * then a recovery will happen and soon that array won't
2403                 * be degraded any more and the spare can go back to sleep then.
2404                 */
2405                nospares = 0;
2406
2407        sync_req = mddev->in_sync;
2408
2409        /* If this is just a dirty<->clean transition, and the array is clean
2410         * and 'events' is odd, we can roll back to the previous clean state */
2411        if (nospares
2412            && (mddev->in_sync && mddev->recovery_cp == MaxSector)
2413            && mddev->can_decrease_events
2414            && mddev->events != 1) {
2415                mddev->events--;
2416                mddev->can_decrease_events = 0;
2417        } else {
2418                /* otherwise we have to go forward and ... */
2419                mddev->events ++;
2420                mddev->can_decrease_events = nospares;
2421        }
2422
2423        if (!mddev->events) {
2424                /*
2425                 * oops, this 64-bit counter should never wrap.
2426                 * Either we are in around ~1 trillion A.C., assuming
2427                 * 1 reboot per second, or we have a bug:
2428                 */
2429                MD_BUG();
2430                mddev->events --;
2431        }
2432
2433        list_for_each_entry(rdev, &mddev->disks, same_set) {
2434                if (rdev->badblocks.changed)
2435                        any_badblocks_changed++;
2436                if (test_bit(Faulty, &rdev->flags))
2437                        set_bit(FaultRecorded, &rdev->flags);
2438        }
2439
2440        sync_sbs(mddev, nospares);
2441        spin_unlock_irq(&mddev->write_lock);
2442
2443        pr_debug("md: updating %s RAID superblock on device (in sync %d)\n",
2444                 mdname(mddev), mddev->in_sync);
2445
2446        bitmap_update_sb(mddev->bitmap);
2447        list_for_each_entry(rdev, &mddev->disks, same_set) {
2448                char b[BDEVNAME_SIZE];
2449
2450                if (rdev->sb_loaded != 1)
2451                        continue; /* no noise on spare devices */
2452
2453                if (!test_bit(Faulty, &rdev->flags) &&
2454                    rdev->saved_raid_disk == -1) {
2455                        md_super_write(mddev,rdev,
2456                                       rdev->sb_start, rdev->sb_size,
2457                                       rdev->sb_page);
2458                        pr_debug("md: (write) %s's sb offset: %llu\n",
2459                                 bdevname(rdev->bdev, b),
2460                                 (unsigned long long)rdev->sb_start);
2461                        rdev->sb_events = mddev->events;
2462                        if (rdev->badblocks.size) {
2463                                md_super_write(mddev, rdev,
2464                                               rdev->badblocks.sector,
2465                                               rdev->badblocks.size << 9,
2466                                               rdev->bb_page);
2467                                rdev->badblocks.size = 0;
2468                        }
2469
2470                } else if (test_bit(Faulty, &rdev->flags))
2471                        pr_debug("md: %s (skipping faulty)\n",
2472                                 bdevname(rdev->bdev, b));
2473                else
2474                        pr_debug("(skipping incremental s/r ");
2475
2476                if (mddev->level == LEVEL_MULTIPATH)
2477                        /* only need to write one superblock... */
2478                        break;
2479        }
2480        md_super_wait(mddev);
2481        /* if there was a failure, MD_CHANGE_DEVS was set, and we re-write super */
2482
2483        spin_lock_irq(&mddev->write_lock);
2484        if (mddev->in_sync != sync_req ||
2485            test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
2486                /* have to write it out again */
2487                spin_unlock_irq(&mddev->write_lock);
2488                goto repeat;
2489        }
2490        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
2491        spin_unlock_irq(&mddev->write_lock);
2492        wake_up(&mddev->sb_wait);
2493        if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2494                sysfs_notify(&mddev->kobj, NULL, "sync_completed");
2495
2496        list_for_each_entry(rdev, &mddev->disks, same_set) {
2497                if (test_and_clear_bit(FaultRecorded, &rdev->flags))
2498                        clear_bit(Blocked, &rdev->flags);
2499
2500                if (any_badblocks_changed)
2501                        md_ack_all_badblocks(&rdev->badblocks);
2502                clear_bit(BlockedBadBlocks, &rdev->flags);
2503                wake_up(&rdev->blocked_wait);
2504        }
2505}
2506
2507/* words written to sysfs files may, or may not, be \n terminated.
2508 * We want to accept with case. For this we use cmd_match.
2509 */
2510static int cmd_match(const char *cmd, const char *str)
2511{
2512        /* See if cmd, written into a sysfs file, matches
2513         * str.  They must either be the same, or cmd can
2514         * have a trailing newline
2515         */
2516        while (*cmd && *str && *cmd == *str) {
2517                cmd++;
2518                str++;
2519        }
2520        if (*cmd == '\n')
2521                cmd++;
2522        if (*str || *cmd)
2523                return 0;
2524        return 1;
2525}
2526
2527struct rdev_sysfs_entry {
2528        struct attribute attr;
2529        ssize_t (*show)(struct md_rdev *, char *);
2530        ssize_t (*store)(struct md_rdev *, const char *, size_t);
2531};
2532
2533static ssize_t
2534state_show(struct md_rdev *rdev, char *page)
2535{
2536        char *sep = "";
2537        size_t len = 0;
2538
2539        if (test_bit(Faulty, &rdev->flags) ||
2540            rdev->badblocks.unacked_exist) {
2541                len+= sprintf(page+len, "%sfaulty",sep);
2542                sep = ",";
2543        }
2544        if (test_bit(In_sync, &rdev->flags)) {
2545                len += sprintf(page+len, "%sin_sync",sep);
2546                sep = ",";
2547        }
2548        if (test_bit(WriteMostly, &rdev->flags)) {
2549                len += sprintf(page+len, "%swrite_mostly",sep);
2550                sep = ",";
2551        }
2552        if (test_bit(Blocked, &rdev->flags) ||
2553            (rdev->badblocks.unacked_exist
2554             && !test_bit(Faulty, &rdev->flags))) {
2555                len += sprintf(page+len, "%sblocked", sep);
2556                sep = ",";
2557        }
2558        if (!test_bit(Faulty, &rdev->flags) &&
2559            !test_bit(In_sync, &rdev->flags)) {
2560                len += sprintf(page+len, "%sspare", sep);
2561                sep = ",";
2562        }
2563        if (test_bit(WriteErrorSeen, &rdev->flags)) {
2564                len += sprintf(page+len, "%swrite_error", sep);
2565                sep = ",";
2566        }
2567        if (test_bit(WantReplacement, &rdev->flags)) {
2568                len += sprintf(page+len, "%swant_replacement", sep);
2569                sep = ",";
2570        }
2571        if (test_bit(Replacement, &rdev->flags)) {
2572                len += sprintf(page+len, "%sreplacement", sep);
2573                sep = ",";
2574        }
2575
2576        return len+sprintf(page+len, "\n");
2577}
2578
2579static ssize_t
2580state_store(struct md_rdev *rdev, const char *buf, size_t len)
2581{
2582        /* can write
2583         *  faulty  - simulates an error
2584         *  remove  - disconnects the device
2585         *  writemostly - sets write_mostly
2586         *  -writemostly - clears write_mostly
2587         *  blocked - sets the Blocked flags
2588         *  -blocked - clears the Blocked and possibly simulates an error
2589         *  insync - sets Insync providing device isn't active
2590         *  write_error - sets WriteErrorSeen
2591         *  -write_error - clears WriteErrorSeen
2592         */
2593        int err = -EINVAL;
2594        if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2595                md_error(rdev->mddev, rdev);
2596                if (test_bit(Faulty, &rdev->flags))
2597                        err = 0;
2598                else
2599                        err = -EBUSY;
2600        } else if (cmd_match(buf, "remove")) {
2601                if (rdev->raid_disk >= 0)
2602                        err = -EBUSY;
2603                else {
2604                        struct mddev *mddev = rdev->mddev;
2605                        kick_rdev_from_array(rdev);
2606                        if (mddev->pers)
2607                                md_update_sb(mddev, 1);
2608                        md_new_event(mddev);
2609                        err = 0;
2610                }
2611        } else if (cmd_match(buf, "writemostly")) {
2612                set_bit(WriteMostly, &rdev->flags);
2613                err = 0;
2614        } else if (cmd_match(buf, "-writemostly")) {
2615                clear_bit(WriteMostly, &rdev->flags);
2616                err = 0;
2617        } else if (cmd_match(buf, "blocked")) {
2618                set_bit(Blocked, &rdev->flags);
2619                err = 0;
2620        } else if (cmd_match(buf, "-blocked")) {
2621                if (!test_bit(Faulty, &rdev->flags) &&
2622                    rdev->badblocks.unacked_exist) {
2623                        /* metadata handler doesn't understand badblocks,
2624                         * so we need to fail the device
2625                         */
2626                        md_error(rdev->mddev, rdev);
2627                }
2628                clear_bit(Blocked, &rdev->flags);
2629                clear_bit(BlockedBadBlocks, &rdev->flags);
2630                wake_up(&rdev->blocked_wait);
2631                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2632                md_wakeup_thread(rdev->mddev->thread);
2633
2634                err = 0;
2635        } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
2636                set_bit(In_sync, &rdev->flags);
2637                err = 0;
2638        } else if (cmd_match(buf, "write_error")) {
2639                set_bit(WriteErrorSeen, &rdev->flags);
2640                err = 0;
2641        } else if (cmd_match(buf, "-write_error")) {
2642                clear_bit(WriteErrorSeen, &rdev->flags);
2643                err = 0;
2644        } else if (cmd_match(buf, "want_replacement")) {
2645                /* Any non-spare device that is not a replacement can
2646                 * become want_replacement at any time, but we then need to
2647                 * check if recovery is needed.
2648                 */
2649                if (rdev->raid_disk >= 0 &&
2650                    !test_bit(Replacement, &rdev->flags))
2651                        set_bit(WantReplacement, &rdev->flags);
2652                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2653                md_wakeup_thread(rdev->mddev->thread);
2654                err = 0;
2655        } else if (cmd_match(buf, "-want_replacement")) {
2656                /* Clearing 'want_replacement' is always allowed.
2657                 * Once replacements starts it is too late though.
2658                 */
2659                err = 0;
2660                clear_bit(WantReplacement, &rdev->flags);
2661        } else if (cmd_match(buf, "replacement")) {
2662                /* Can only set a device as a replacement when array has not
2663                 * yet been started.  Once running, replacement is automatic
2664                 * from spares, or by assigning 'slot'.
2665                 */
2666                if (rdev->mddev->pers)
2667                        err = -EBUSY;
2668                else {
2669                        set_bit(Replacement, &rdev->flags);
2670                        err = 0;
2671                }
2672        } else if (cmd_match(buf, "-replacement")) {
2673                /* Similarly, can only clear Replacement before start */
2674                if (rdev->mddev->pers)
2675                        err = -EBUSY;
2676                else {
2677                        clear_bit(Replacement, &rdev->flags);
2678                        err = 0;
2679                }
2680        }
2681        if (!err)
2682                sysfs_notify_dirent_safe(rdev->sysfs_state);
2683        return err ? err : len;
2684}
2685static struct rdev_sysfs_entry rdev_state =
2686__ATTR(state, S_IRUGO|S_IWUSR, state_show, state_store);
2687
2688static ssize_t
2689errors_show(struct md_rdev *rdev, char *page)
2690{
2691        return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
2692}
2693
2694static ssize_t
2695errors_store(struct md_rdev *rdev, const char *buf, size_t len)
2696{
2697        char *e;
2698        unsigned long n = simple_strtoul(buf, &e, 10);
2699        if (*buf && (*e == 0 || *e == '\n')) {
2700                atomic_set(&rdev->corrected_errors, n);
2701                return len;
2702        }
2703        return -EINVAL;
2704}
2705static struct rdev_sysfs_entry rdev_errors =
2706__ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
2707
2708static ssize_t
2709slot_show(struct md_rdev *rdev, char *page)
2710{
2711        if (rdev->raid_disk < 0)
2712                return sprintf(page, "none\n");
2713        else
2714                return sprintf(page, "%d\n", rdev->raid_disk);
2715}
2716
2717static ssize_t
2718slot_store(struct md_rdev *rdev, const char *buf, size_t len)
2719{
2720        char *e;
2721        int err;
2722        int slot = simple_strtoul(buf, &e, 10);
2723        if (strncmp(buf, "none", 4)==0)
2724                slot = -1;
2725        else if (e==buf || (*e && *e!= '\n'))
2726                return -EINVAL;
2727        if (rdev->mddev->pers && slot == -1) {
2728                /* Setting 'slot' on an active array requires also
2729                 * updating the 'rd%d' link, and communicating
2730                 * with the personality with ->hot_*_disk.
2731                 * For now we only support removing
2732                 * failed/spare devices.  This normally happens automatically,
2733                 * but not when the metadata is externally managed.
2734                 */
2735                if (rdev->raid_disk == -1)
2736                        return -EEXIST;
2737                /* personality does all needed checks */
2738                if (rdev->mddev->pers->hot_remove_disk == NULL)
2739                        return -EINVAL;
2740                err = rdev->mddev->pers->
2741                        hot_remove_disk(rdev->mddev, rdev);
2742                if (err)
2743                        return err;
2744                sysfs_unlink_rdev(rdev->mddev, rdev);
2745                rdev->raid_disk = -1;
2746                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
2747                md_wakeup_thread(rdev->mddev->thread);
2748        } else if (rdev->mddev->pers) {
2749                /* Activating a spare .. or possibly reactivating
2750                 * if we ever get bitmaps working here.
2751                 */
2752
2753                if (rdev->raid_disk != -1)
2754                        return -EBUSY;
2755
2756                if (test_bit(MD_RECOVERY_RUNNING, &rdev->mddev->recovery))
2757                        return -EBUSY;
2758
2759                if (rdev->mddev->pers->hot_add_disk == NULL)
2760                        return -EINVAL;
2761
2762                if (slot >= rdev->mddev->raid_disks &&
2763                    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2764                        return -ENOSPC;
2765
2766                rdev->raid_disk = slot;
2767                if (test_bit(In_sync, &rdev->flags))
2768                        rdev->saved_raid_disk = slot;
2769                else
2770                        rdev->saved_raid_disk = -1;
2771                clear_bit(In_sync, &rdev->flags);
2772                err = rdev->mddev->pers->
2773                        hot_add_disk(rdev->mddev, rdev);
2774                if (err) {
2775                        rdev->raid_disk = -1;
2776                        return err;
2777                } else
2778                        sysfs_notify_dirent_safe(rdev->sysfs_state);
2779                if (sysfs_link_rdev(rdev->mddev, rdev))
2780                        /* failure here is OK */;
2781                /* don't wakeup anyone, leave that to userspace. */
2782        } else {
2783                if (slot >= rdev->mddev->raid_disks &&
2784                    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
2785                        return -ENOSPC;
2786                rdev->raid_disk = slot;
2787                /* assume it is working */
2788                clear_bit(Faulty, &rdev->flags);
2789                clear_bit(WriteMostly, &rdev->flags);
2790                set_bit(In_sync, &rdev->flags);
2791                sysfs_notify_dirent_safe(rdev->sysfs_state);
2792        }
2793        return len;
2794}
2795
2796
2797static struct rdev_sysfs_entry rdev_slot =
2798__ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
2799
2800static ssize_t
2801offset_show(struct md_rdev *rdev, char *page)
2802{
2803        return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
2804}
2805
2806static ssize_t
2807offset_store(struct md_rdev *rdev, const char *buf, size_t len)
2808{
2809        char *e;
2810        unsigned long long offset = simple_strtoull(buf, &e, 10);
2811        if (e==buf || (*e && *e != '\n'))
2812                return -EINVAL;
2813        if (rdev->mddev->pers && rdev->raid_disk >= 0)
2814                return -EBUSY;
2815        if (rdev->sectors && rdev->mddev->external)
2816                /* Must set offset before size, so overlap checks
2817                 * can be sane */
2818                return -EBUSY;
2819        rdev->data_offset = offset;
2820        return len;
2821}
2822
2823static struct rdev_sysfs_entry rdev_offset =
2824__ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
2825
2826static ssize_t
2827rdev_size_show(struct md_rdev *rdev, char *page)
2828{
2829        return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
2830}
2831
2832static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
2833{
2834        /* check if two start/length pairs overlap */
2835        if (s1+l1 <= s2)
2836                return 0;
2837        if (s2+l2 <= s1)
2838                return 0;
2839        return 1;
2840}
2841
2842static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
2843{
2844        unsigned long long blocks;
2845        sector_t new;
2846
2847        if (strict_strtoull(buf, 10, &blocks) < 0)
2848                return -EINVAL;
2849
2850        if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
2851                return -EINVAL; /* sector conversion overflow */
2852
2853        new = blocks * 2;
2854        if (new != blocks * 2)
2855                return -EINVAL; /* unsigned long long to sector_t overflow */
2856
2857        *sectors = new;
2858        return 0;
2859}
2860
2861static ssize_t
2862rdev_size_store(struct md_rdev *rdev, const char *buf, size_t len)
2863{
2864        struct mddev *my_mddev = rdev->mddev;
2865        sector_t oldsectors = rdev->sectors;
2866        sector_t sectors;
2867
2868        if (strict_blocks_to_sectors(buf, &sectors) < 0)
2869                return -EINVAL;
2870        if (my_mddev->pers && rdev->raid_disk >= 0) {
2871                if (my_mddev->persistent) {
2872                        sectors = super_types[my_mddev->major_version].
2873                                rdev_size_change(rdev, sectors);
2874                        if (!sectors)
2875                                return -EBUSY;
2876                } else if (!sectors)
2877                        sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
2878                                rdev->data_offset;
2879        }
2880        if (sectors < my_mddev->dev_sectors)
2881                return -EINVAL; /* component must fit device */
2882
2883        rdev->sectors = sectors;
2884        if (sectors > oldsectors && my_mddev->external) {
2885                /* need to check that all other rdevs with the same ->bdev
2886                 * do not overlap.  We need to unlock the mddev to avoid
2887                 * a deadlock.  We have already changed rdev->sectors, and if
2888                 * we have to change it back, we will have the lock again.
2889                 */
2890                struct mddev *mddev;
2891                int overlap = 0;
2892                struct list_head *tmp;
2893
2894                mddev_unlock(my_mddev);
2895                for_each_mddev(mddev, tmp) {
2896                        struct md_rdev *rdev2;
2897
2898                        mddev_lock(mddev);
2899                        list_for_each_entry(rdev2, &mddev->disks, same_set)
2900                                if (rdev->bdev == rdev2->bdev &&
2901                                    rdev != rdev2 &&
2902                                    overlaps(rdev->data_offset, rdev->sectors,
2903                                             rdev2->data_offset,
2904                                             rdev2->sectors)) {
2905                                        overlap = 1;
2906                                        break;
2907                                }
2908                        mddev_unlock(mddev);
2909                        if (overlap) {
2910                                mddev_put(mddev);
2911                                break;
2912                        }
2913                }
2914                mddev_lock(my_mddev);
2915                if (overlap) {
2916                        /* Someone else could have slipped in a size
2917                         * change here, but doing so is just silly.
2918                         * We put oldsectors back because we *know* it is
2919                         * safe, and trust userspace not to race with
2920                         * itself
2921                         */
2922                        rdev->sectors = oldsectors;
2923                        return -EBUSY;
2924                }
2925        }
2926        return len;
2927}
2928
2929static struct rdev_sysfs_entry rdev_size =
2930__ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
2931
2932
2933static ssize_t recovery_start_show(struct md_rdev *rdev, char *page)
2934{
2935        unsigned long long recovery_start = rdev->recovery_offset;
2936
2937        if (test_bit(In_sync, &rdev->flags) ||
2938            recovery_start == MaxSector)
2939                return sprintf(page, "none\n");
2940
2941        return sprintf(page, "%llu\n", recovery_start);
2942}
2943
2944static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_t len)
2945{
2946        unsigned long long recovery_start;
2947
2948        if (cmd_match(buf, "none"))
2949                recovery_start = MaxSector;
2950        else if (strict_strtoull(buf, 10, &recovery_start))
2951                return -EINVAL;
2952
2953        if (rdev->mddev->pers &&
2954            rdev->raid_disk >= 0)
2955                return -EBUSY;
2956
2957        rdev->recovery_offset = recovery_start;
2958        if (recovery_start == MaxSector)
2959                set_bit(In_sync, &rdev->flags);
2960        else
2961                clear_bit(In_sync, &rdev->flags);
2962        return len;
2963}
2964
2965static struct rdev_sysfs_entry rdev_recovery_start =
2966__ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store);
2967
2968
2969static ssize_t
2970badblocks_show(struct badblocks *bb, char *page, int unack);
2971static ssize_t
2972badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack);
2973
2974static ssize_t bb_show(struct md_rdev *rdev, char *page)
2975{
2976        return badblocks_show(&rdev->badblocks, page, 0);
2977}
2978static ssize_t bb_store(struct md_rdev *rdev, const char *page, size_t len)
2979{
2980        int rv = badblocks_store(&rdev->badblocks, page, len, 0);
2981        /* Maybe that ack was all we needed */
2982        if (test_and_clear_bit(BlockedBadBlocks, &rdev->flags))
2983                wake_up(&rdev->blocked_wait);
2984        return rv;
2985}
2986static struct rdev_sysfs_entry rdev_bad_blocks =
2987__ATTR(bad_blocks, S_IRUGO|S_IWUSR, bb_show, bb_store);
2988
2989
2990static ssize_t ubb_show(struct md_rdev *rdev, char *page)
2991{
2992        return badblocks_show(&rdev->badblocks, page, 1);
2993}
2994static ssize_t ubb_store(struct md_rdev *rdev, const char *page, size_t len)
2995{
2996        return badblocks_store(&rdev->badblocks, page, len, 1);
2997}
2998static struct rdev_sysfs_entry rdev_unack_bad_blocks =
2999__ATTR(unacknowledged_bad_blocks, S_IRUGO|S_IWUSR, ubb_show, ubb_store);
3000
3001static struct attribute *rdev_default_attrs[] = {
3002        &rdev_state.attr,
3003        &rdev_errors.attr,
3004        &rdev_slot.attr,
3005        &rdev_offset.attr,
3006        &rdev_size.attr,
3007        &rdev_recovery_start.attr,
3008        &rdev_bad_blocks.attr,
3009        &rdev_unack_bad_blocks.attr,
3010        NULL,
3011};
3012static ssize_t
3013rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3014{
3015        struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3016        struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3017        struct mddev *mddev = rdev->mddev;
3018        ssize_t rv;
3019
3020        if (!entry->show)
3021                return -EIO;
3022
3023        rv = mddev ? mddev_lock(mddev) : -EBUSY;
3024        if (!rv) {
3025                if (rdev->mddev == NULL)
3026                        rv = -EBUSY;
3027                else
3028                        rv = entry->show(rdev, page);
3029                mddev_unlock(mddev);
3030        }
3031        return rv;
3032}
3033
3034static ssize_t
3035rdev_attr_store(struct kobject *kobj, struct attribute *attr,
3036              const char *page, size_t length)
3037{
3038        struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3039        struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3040        ssize_t rv;
3041        struct mddev *mddev = rdev->mddev;
3042
3043        if (!entry->store)
3044                return -EIO;
3045        if (!capable(CAP_SYS_ADMIN))
3046                return -EACCES;
3047        rv = mddev ? mddev_lock(mddev): -EBUSY;
3048        if (!rv) {
3049                if (rdev->mddev == NULL)
3050                        rv = -EBUSY;
3051                else
3052                        rv = entry->store(rdev, page, length);
3053                mddev_unlock(mddev);
3054        }
3055        return rv;
3056}
3057
3058static void rdev_free(struct kobject *ko)
3059{
3060        struct md_rdev *rdev = container_of(ko, struct md_rdev, kobj);
3061        kfree(rdev);
3062}
3063static const struct sysfs_ops rdev_sysfs_ops = {
3064        .show           = rdev_attr_show,
3065        .store          = rdev_attr_store,
3066};
3067static struct kobj_type rdev_ktype = {
3068        .release        = rdev_free,
3069        .sysfs_ops      = &rdev_sysfs_ops,
3070        .default_attrs  = rdev_default_attrs,
3071};
3072
3073int md_rdev_init(struct md_rdev *rdev)
3074{
3075        rdev->desc_nr = -1;
3076        rdev->saved_raid_disk = -1;
3077        rdev->raid_disk = -1;
3078        rdev->flags = 0;
3079        rdev->data_offset = 0;
3080        rdev->sb_events = 0;
3081        rdev->last_read_error.tv_sec  = 0;
3082        rdev->last_read_error.tv_nsec = 0;
3083        rdev->sb_loaded = 0;
3084        rdev->bb_page = NULL;
3085        atomic_set(&rdev->nr_pending, 0);
3086        atomic_set(&rdev->read_errors, 0);
3087        atomic_set(&rdev->corrected_errors, 0);
3088
3089        INIT_LIST_HEAD(&rdev->same_set);
3090        init_waitqueue_head(&rdev->blocked_wait);
3091
3092        /* Add space to store bad block list.
3093         * This reserves the space even on arrays where it cannot
3094         * be used - I wonder if that matters
3095         */
3096        rdev->badblocks.count = 0;
3097        rdev->badblocks.shift = 0;
3098        rdev->badblocks.page = kmalloc(PAGE_SIZE, GFP_KERNEL);
3099        seqlock_init(&rdev->badblocks.lock);
3100        if (rdev->badblocks.page == NULL)
3101                return -ENOMEM;
3102
3103        return 0;
3104}
3105EXPORT_SYMBOL_GPL(md_rdev_init);
3106/*
3107 * Import a device. If 'super_format' >= 0, then sanity check the superblock
3108 *
3109 * mark the device faulty if:
3110 *
3111 *   - the device is nonexistent (zero size)
3112 *   - the device has no valid superblock
3113 *
3114 * a faulty rdev _never_ has rdev->sb set.
3115 */
3116static struct md_rdev *md_import_device(dev_t newdev, int super_format, int super_minor)
3117{
3118        char b[BDEVNAME_SIZE];
3119        int err;
3120        struct md_rdev *rdev;
3121        sector_t size;
3122
3123        rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
3124        if (!rdev) {
3125                printk(KERN_ERR "md: could not alloc mem for new device!\n");
3126                return ERR_PTR(-ENOMEM);
3127        }
3128
3129        err = md_rdev_init(rdev);
3130        if (err)
3131                goto abort_free;
3132        err = alloc_disk_sb(rdev);
3133        if (err)
3134                goto abort_free;
3135
3136        err = lock_rdev(rdev, newdev, super_format == -2);
3137        if (err)
3138                goto abort_free;
3139
3140        kobject_init(&rdev->kobj, &rdev_ktype);
3141
3142        size = i_size_read(rdev->bdev->bd_inode) >> BLOCK_SIZE_BITS;
3143        if (!size) {
3144                printk(KERN_WARNING 
3145                        "md: %s has zero or unknown size, marking faulty!\n",
3146                        bdevname(rdev->bdev,b));
3147                err = -EINVAL;
3148                goto abort_free;
3149        }
3150
3151        if (super_format >= 0) {
3152                err = super_types[super_format].
3153                        load_super(rdev, NULL, super_minor);
3154                if (err == -EINVAL) {
3155                        printk(KERN_WARNING
3156                                "md: %s does not have a valid v%d.%d "
3157                               "superblock, not importing!\n",
3158                                bdevname(rdev->bdev,b),
3159                               super_format, super_minor);
3160                        goto abort_free;
3161                }
3162                if (err < 0) {
3163                        printk(KERN_WARNING 
3164                                "md: could not read %s's sb, not importing!\n",
3165                                bdevname(rdev->bdev,b));
3166                        goto abort_free;
3167                }
3168        }
3169        if (super_format == -1)
3170                /* hot-add for 0.90, or non-persistent: so no badblocks */
3171                rdev->badblocks.shift = -1;
3172
3173        return rdev;
3174
3175abort_free:
3176        if (rdev->bdev)
3177                unlock_rdev(rdev);
3178        free_disk_sb(rdev);
3179        kfree(rdev->badblocks.page);
3180        kfree(rdev);
3181        return ERR_PTR(err);
3182}
3183
3184/*
3185 * Check a full RAID array for plausibility
3186 */
3187
3188
3189static void analyze_sbs(struct mddev * mddev)
3190{
3191        int i;
3192        struct md_rdev *rdev, *freshest, *tmp;
3193        char b[BDEVNAME_SIZE];
3194
3195        freshest = NULL;
3196        rdev_for_each(rdev, tmp, mddev)
3197                switch (super_types[mddev->major_version].
3198                        load_super(rdev, freshest, mddev->minor_version)) {
3199                case 1:
3200                        freshest = rdev;
3201                        break;
3202                case 0:
3203                        break;
3204                default:
3205                        printk( KERN_ERR \
3206                                "md: fatal superblock inconsistency in %s"
3207                                " -- removing from array\n", 
3208                                bdevname(rdev->bdev,b));
3209                        kick_rdev_from_array(rdev);
3210                }
3211
3212
3213        super_types[mddev->major_version].
3214                validate_super(mddev, freshest);
3215
3216        i = 0;
3217        rdev_for_each(rdev, tmp, mddev) {
3218                if (mddev->max_disks &&
3219                    (rdev->desc_nr >= mddev->max_disks ||
3220                     i > mddev->max_disks)) {
3221                        printk(KERN_WARNING
3222                               "md: %s: %s: only %d devices permitted\n",
3223                               mdname(mddev), bdevname(rdev->bdev, b),
3224                               mddev->max_disks);
3225                        kick_rdev_from_array(rdev);
3226                        continue;
3227                }
3228                if (rdev != freshest)
3229                        if (super_types[mddev->major_version].
3230                            validate_super(mddev, rdev)) {
3231                                printk(KERN_WARNING "md: kicking non-fresh %s"
3232                                        " from array!\n",
3233                                        bdevname(rdev->bdev,b));
3234                                kick_rdev_from_array(rdev);
3235                                continue;
3236                        }
3237                if (mddev->level == LEVEL_MULTIPATH) {
3238                        rdev->desc_nr = i++;
3239                        rdev->raid_disk = rdev->desc_nr;
3240                        set_bit(In_sync, &rdev->flags);
3241                } else if (rdev->raid_disk >= (mddev->raid_disks - min(0, mddev->delta_disks))) {
3242                        rdev->raid_disk = -1;
3243                        clear_bit(In_sync, &rdev->flags);
3244                }
3245        }
3246}
3247
3248/* Read a fixed-point number.
3249 * Numbers in sysfs attributes should be in "standard" units where
3250 * possible, so time should be in seconds.
3251 * However we internally use a a much smaller unit such as 
3252 * milliseconds or jiffies.
3253 * This function takes a decimal number with a possible fractional
3254 * component, and produces an integer which is the result of
3255 * multiplying that number by 10^'scale'.
3256 * all without any floating-point arithmetic.
3257 */
3258int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale)
3259{
3260        unsigned long result = 0;
3261        long decimals = -1;
3262        while (isdigit(*cp) || (*cp == '.' && decimals < 0)) {
3263                if (*cp == '.')
3264                        decimals = 0;
3265                else if (decimals < scale) {
3266                        unsigned int value;
3267                        value = *cp - '0';
3268                        result = result * 10 + value;
3269                        if (decimals >= 0)
3270                                decimals++;
3271                }
3272                cp++;
3273        }
3274        if (*cp == '\n')
3275                cp++;
3276        if (*cp)
3277                return -EINVAL;
3278        if (decimals < 0)
3279                decimals = 0;
3280        while (decimals < scale) {
3281                result *= 10;
3282                decimals ++;
3283        }
3284        *res = result;
3285        return 0;
3286}
3287
3288
3289static void md_safemode_timeout(unsigned long data);
3290
3291static ssize_t
3292safe_delay_show(struct mddev *mddev, char *page)
3293{
3294        int msec = (mddev->safemode_delay*1000)/HZ;
3295        return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
3296}
3297static ssize_t
3298safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
3299{
3300        unsigned long msec;
3301
3302        if (strict_strtoul_scaled(cbuf, &msec, 3) < 0)
3303                return -EINVAL;
3304        if (msec == 0)
3305                mddev->safemode_delay = 0;
3306        else {
3307                unsigned long old_delay = mddev->safemode_delay;
3308                mddev->safemode_delay = (msec*HZ)/1000;
3309                if (mddev->safemode_delay == 0)
3310                        mddev->safemode_delay = 1;
3311                if (mddev->safemode_delay < old_delay)
3312                        md_safemode_timeout((unsigned long)mddev);
3313        }
3314        return len;
3315}
3316static struct md_sysfs_entry md_safe_delay =
3317__ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
3318
3319static ssize_t
3320level_show(struct mddev *mddev, char *page)
3321{
3322        struct md_personality *p = mddev->pers;
3323        if (p)
3324                return sprintf(page, "%s\n", p->name);
3325        else if (mddev->clevel[0])
3326                return sprintf(page, "%s\n", mddev->clevel);
3327        else if (mddev->level != LEVEL_NONE)
3328                return sprintf(page, "%d\n", mddev->level);
3329        else
3330                return 0;
3331}
3332
3333static ssize_t
3334level_store(struct mddev *mddev, const char *buf, size_t len)
3335{
3336        char clevel[16];
3337        ssize_t rv = len;
3338        struct md_personality *pers;
3339        long level;
3340        void *priv;
3341        struct md_rdev *rdev;
3342
3343        if (mddev->pers == NULL) {
3344                if (len == 0)
3345                        return 0;
3346                if (len >= sizeof(mddev->clevel))
3347                        return -ENOSPC;
3348                strncpy(mddev->clevel, buf, len);
3349                if (mddev->clevel[len-1] == '\n')
3350                        len--;
3351                mddev->clevel[len] = 0;
3352                mddev->level = LEVEL_NONE;
3353                return rv;
3354        }
3355
3356        /* request to change the personality.  Need to ensure:
3357         *  - array is not engaged in resync/recovery/reshape
3358         *  - old personality can be suspended
3359         *  - new personality will access other array.
3360         */
3361
3362        if (mddev->sync_thread ||
3363            mddev->reshape_position != MaxSector ||
3364            mddev->sysfs_active)
3365                return -EBUSY;
3366
3367        if (!mddev->pers->quiesce) {
3368                printk(KERN_WARNING "md: %s: %s does not support online personality change\n",
3369                       mdname(mddev), mddev->pers->name);
3370                return -EINVAL;
3371        }
3372
3373        /* Now find the new personality */
3374        if (len == 0 || len >= sizeof(clevel))
3375                return -EINVAL;
3376        strncpy(clevel, buf, len);
3377        if (clevel[len-1] == '\n')
3378                len--;
3379        clevel[len] = 0;
3380        if (strict_strtol(clevel, 10, &level))
3381                level = LEVEL_NONE;
3382
3383        if (request_module("md-%s", clevel) != 0)
3384                request_module("md-level-%s", clevel);
3385        spin_lock(&pers_lock);
3386        pers = find_pers(level, clevel);
3387        if (!pers || !try_module_get(pers->owner)) {
3388                spin_unlock(&pers_lock);
3389                printk(KERN_WARNING "md: personality %s not loaded\n", clevel);
3390                return -EINVAL;
3391        }
3392        spin_unlock(&pers_lock);
3393
3394        if (pers == mddev->pers) {
3395                /* Nothing to do! */
3396                module_put(pers->owner);
3397                return rv;
3398        }
3399        if (!pers->takeover) {
3400                module_put(pers->owner);
3401                printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
3402                       mdname(mddev), clevel);
3403                return -EINVAL;
3404        }
3405
3406        list_for_each_entry(rdev, &mddev->disks, same_set)
3407                rdev->new_raid_disk = rdev->raid_disk;
3408
3409        /* ->takeover must set new_* and/or delta_disks
3410         * if it succeeds, and may set them when it fails.
3411         */
3412        priv = pers->takeover(mddev);
3413        if (IS_ERR(priv)) {
3414                mddev->new_level = mddev->level;
3415                mddev->new_layout = mddev->layout;
3416                mddev->new_chunk_sectors = mddev->chunk_sectors;
3417                mddev->raid_disks -= mddev->delta_disks;
3418                mddev->delta_disks = 0;
3419                module_put(pers->owner);
3420                printk(KERN_WARNING "md: %s: %s would not accept array\n",
3421                       mdname(mddev), clevel);
3422                return PTR_ERR(priv);
3423        }
3424
3425        /* Looks like we have a winner */
3426        mddev_suspend(mddev);
3427        mddev->pers->stop(mddev);
3428        
3429        if (mddev->pers->sync_request == NULL &&
3430            pers->sync_request != NULL) {
3431                /* need to add the md_redundancy_group */
3432                if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
3433                        printk(KERN_WARNING
3434                               "md: cannot register extra attributes for %s\n",
3435                               mdname(mddev));
3436                mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, NULL, "sync_action");
3437        }               
3438        if (mddev->pers->sync_request != NULL &&
3439            pers->sync_request == NULL) {
3440                /* need to remove the md_redundancy_group */
3441                if (mddev->to_remove == NULL)
3442                        mddev->to_remove = &md_redundancy_group;
3443        }
3444
3445        if (mddev->pers->sync_request == NULL &&
3446            mddev->external) {
3447                /* We are converting from a no-redundancy array
3448                 * to a redundancy array and metadata is managed
3449                 * externally so we need to be sure that writes
3450                 * won't block due to a need to transition
3451                 *      clean->dirty
3452                 * until external management is started.
3453                 */
3454                mddev->in_sync = 0;
3455                mddev->safemode_delay = 0;
3456                mddev->safemode = 0;
3457        }
3458
3459        list_for_each_entry(rdev, &mddev->disks, same_set) {
3460                if (rdev->raid_disk < 0)
3461                        continue;
3462                if (rdev->new_raid_disk >= mddev->raid_disks)
3463                        rdev->new_raid_disk = -1;
3464                if (rdev->new_raid_disk == rdev->raid_disk)
3465                        continue;
3466                sysfs_unlink_rdev(mddev, rdev);
3467        }
3468        list_for_each_entry(rdev, &mddev->disks, same_set) {
3469                if (rdev->raid_disk < 0)
3470                        continue;
3471                if (rdev->new_raid_disk == rdev->raid_disk)
3472                        continue;
3473                rdev->raid_disk = rdev->new_raid_disk;
3474                if (rdev->raid_disk < 0)
3475                        clear_bit(In_sync, &rdev->flags);
3476                else {
3477                        if (sysfs_link_rdev(mddev, rdev))
3478                                printk(KERN_WARNING "md: cannot register rd%d"
3479                                       " for %s after level change\n",
3480                                       rdev->raid_disk, mdname(mddev));
3481                }
3482        }
3483
3484        module_put(mddev->pers->owner);
3485        mddev->pers = pers;
3486        mddev->private = priv;
3487        strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
3488        mddev->level = mddev->new_level;
3489        mddev->layout = mddev->new_layout;
3490        mddev->chunk_sectors = mddev->new_chunk_sectors;
3491        mddev->delta_disks = 0;
3492        mddev->degraded = 0;
3493        if (mddev->pers->sync_request == NULL) {
3494                /* this is now an array without redundancy, so
3495                 * it must always be in_sync
3496                 */
3497                mddev->in_sync = 1;
3498                del_timer_sync(&mddev->safemode_timer);
3499        }
3500        pers->run(mddev);
3501        mddev_resume(mddev);
3502        set_bit(MD_CHANGE_DEVS, &mddev->flags);
3503        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3504        md_wakeup_thread(mddev->thread);
3505        sysfs_notify(&mddev->kobj, NULL, "level");
3506        md_new_event(mddev);
3507        return rv;
3508}
3509
3510static struct md_sysfs_entry md_level =
3511__ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
3512
3513
3514static ssize_t
3515layout_show(struct mddev *mddev, char *page)
3516{
3517        /* just a number, not meaningful for all levels */
3518        if (mddev->reshape_position != MaxSector &&
3519            mddev->layout != mddev->new_layout)
3520                return sprintf(page, "%d (%d)\n",
3521                               mddev->new_layout, mddev->layout);
3522        return sprintf(page, "%d\n", mddev->layout);
3523}
3524
3525static ssize_t
3526layout_store(struct mddev *mddev, const char *buf, size_t len)
3527{
3528        char *e;
3529        unsigned long n = simple_strtoul(buf, &e, 10);
3530
3531        if (!*buf || (*e && *e != '\n'))
3532                return -EINVAL;
3533
3534        if (mddev->pers) {
3535                int err;
3536                if (mddev->pers->check_reshape == NULL)
3537                        return -EBUSY;
3538                mddev->new_layout = n;
3539                err = mddev->pers->check_reshape(mddev);
3540                if (err) {
3541                        mddev->new_layout = mddev->layout;
3542                        return err;
3543                }
3544        } else {
3545                mddev->new_layout = n;
3546                if (mddev->reshape_position == MaxSector)
3547                        mddev->layout = n;
3548        }
3549        return len;
3550}
3551static struct md_sysfs_entry md_layout =
3552__ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
3553
3554
3555static ssize_t
3556raid_disks_show(struct mddev *mddev, char *page)
3557{
3558        if (mddev->raid_disks == 0)
3559                return 0;
3560        if (mddev->reshape_position != MaxSector &&
3561            mddev->delta_disks != 0)
3562                return sprintf(page, "%d (%d)\n", mddev->raid_disks,
3563                               mddev->raid_disks - mddev->delta_disks);
3564        return sprintf(page, "%d\n", mddev->raid_disks);
3565}
3566
3567static int update_raid_disks(struct mddev *mddev, int raid_disks);
3568
3569static ssize_t
3570raid_disks_store(struct mddev *mddev, const char *buf, size_t len)
3571{
3572        char *e;
3573        int rv = 0;
3574        unsigned long n = simple_strtoul(buf, &e, 10);
3575
3576        if (!*buf || (*e && *e != '\n'))
3577                return -EINVAL;
3578
3579        if (mddev->pers)
3580                rv = update_raid_disks(mddev, n);
3581        else if (mddev->reshape_position != MaxSector) {
3582                int olddisks = mddev->raid_disks - mddev->delta_disks;
3583                mddev->delta_disks = n - olddisks;
3584                mddev->raid_disks = n;
3585        } else
3586                mddev->raid_disks = n;
3587        return rv ? rv : len;
3588}
3589static struct md_sysfs_entry md_raid_disks =
3590__ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
3591
3592static ssize_t
3593chunk_size_show(struct mddev *mddev, char *page)
3594{
3595        if (mddev->reshape_position != MaxSector &&
3596            mddev->chunk_sectors != mddev->new_chunk_sectors)
3597                return sprintf(page, "%d (%d)\n",
3598                               mddev->new_chunk_sectors << 9,
3599                               mddev->chunk_sectors << 9);
3600        return sprintf(page, "%d\n", mddev->chunk_sectors << 9);
3601}
3602
3603static ssize_t
3604chunk_size_store(struct mddev *mddev, const char *buf, size_t len)
3605{
3606        char *e;
3607        unsigned long n = simple_strtoul(buf, &e, 10);
3608
3609        if (!*buf || (*e && *e != '\n'))
3610                return -EINVAL;
3611
3612        if (mddev->pers) {
3613                int err;
3614                if (mddev->pers->check_reshape == NULL)
3615                        return -EBUSY;
3616                mddev->new_chunk_sectors = n >> 9;
3617                err = mddev->pers->check_reshape(mddev);
3618                if (err) {
3619                        mddev->new_chunk_sectors = mddev->chunk_sectors;
3620                        return err;
3621                }
3622        } else {
3623                mddev->new_chunk_sectors = n >> 9;
3624                if (mddev->reshape_position == MaxSector)
3625                        mddev->chunk_sectors = n >> 9;
3626        }
3627        return len;
3628}
3629static struct md_sysfs_entry md_chunk_size =
3630__ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
3631
3632static ssize_t
3633resync_start_show(struct mddev *mddev, char *page)
3634{
3635        if (mddev->recovery_cp == MaxSector)
3636                return sprintf(page, "none\n");
3637        return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
3638}
3639
3640static ssize_t
3641resync_start_store(struct mddev *mddev, const char *buf, size_t len)
3642{
3643        char *e;
3644        unsigned long long n = simple_strtoull(buf, &e, 10);
3645
3646        if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
3647                return -EBUSY;
3648        if (cmd_match(buf, "none"))
3649                n = MaxSector;
3650        else if (!*buf || (*e && *e != '\n'))
3651                return -EINVAL;
3652
3653        mddev->recovery_cp = n;
3654        return len;
3655}
3656static struct md_sysfs_entry md_resync_start =
3657__ATTR(resync_start, S_IRUGO|S_IWUSR, resync_start_show, resync_start_store);
3658
3659/*
3660 * The array state can be:
3661 *
3662 * clear
3663 *     No devices, no size, no level
3664 *     Equivalent to STOP_ARRAY ioctl
3665 * inactive
3666 *     May have some settings, but array is not active
3667 *        all IO results in error
3668 *     When written, doesn't tear down array, but just stops it
3669 * suspended (not supported yet)
3670 *     All IO requests will block. The array can be reconfigured.
3671 *     Writing this, if accepted, will block until array is quiescent
3672 * readonly
3673 *     no resync can happen.  no superblocks get written.
3674 *     write requests fail
3675 * read-auto
3676 *     like readonly, but behaves like 'clean' on a write request.
3677 *
3678 * clean - no pending writes, but otherwise active.
3679 *     When written to inactive array, starts without resync
3680 *     If a write request arrives then
3681 *       if metadata is known, mark 'dirty' and switch to 'active'.
3682 *       if not known, block and switch to write-pending
3683 *     If written to an active array that has pending writes, then fails.
3684 * active
3685 *     fully active: IO and resync can be happening.
3686 *     When written to inactive array, starts with resync
3687 *
3688 * write-pending
3689 *     clean, but writes are blocked waiting for 'active' to be written.
3690 *
3691 * active-idle
3692 *     like active, but no writes have been seen for a while (100msec).
3693 *
3694 */
3695enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
3696                   write_pending, active_idle, bad_word};
3697static char *array_states[] = {
3698        "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
3699        "write-pending", "active-idle", NULL };
3700
3701static int match_word(const char *word, char **list)
3702{
3703        int n;
3704        for (n=0; list[n]; n++)
3705                if (cmd_match(word, list[n]))
3706                        break;
3707        return n;
3708}
3709
3710static ssize_t
3711array_state_show(struct mddev *mddev, char *page)
3712{
3713        enum array_state st = inactive;
3714
3715        if (mddev->pers)
3716                switch(mddev->ro) {
3717                case 1:
3718                        st = readonly;
3719                        break;
3720                case 2:
3721                        st = read_auto;
3722                        break;
3723                case 0:
3724                        if (mddev->in_sync)
3725                                st = clean;
3726                        else if (test_bit(MD_CHANGE_PENDING, &mddev->flags))
3727                                st = write_pending;
3728                        else if (mddev->safemode)
3729                                st = active_idle;
3730                        else
3731                                st = active;
3732                }
3733        else {
3734                if (list_empty(&mddev->disks) &&
3735                    mddev->raid_disks == 0 &&
3736                    mddev->dev_sectors == 0)
3737                        st = clear;
3738                else
3739                        st = inactive;
3740        }
3741        return sprintf(page, "%s\n", array_states[st]);
3742}
3743
3744static int do_md_stop(struct mddev * mddev, int ro, int is_open);
3745static int md_set_readonly(struct mddev * mddev, int is_open);
3746static int do_md_run(struct mddev * mddev);
3747static int restart_array(struct mddev *mddev);
3748
3749static ssize_t
3750array_state_store(struct mddev *mddev, const char *buf, size_t len)
3751{
3752        int err = -EINVAL;
3753        enum array_state st = match_word(buf, array_states);
3754        switch(st) {
3755        case bad_word:
3756                break;
3757        case clear:
3758                /* stopping an active array */
3759                if (atomic_read(&mddev->openers) > 0)
3760                        return -EBUSY;
3761                err = do_md_stop(mddev, 0, 0);
3762                break;
3763        case inactive:
3764                /* stopping an active array */
3765                if (mddev->pers) {
3766                        if (atomic_read(&mddev->openers) > 0)
3767                                return -EBUSY;
3768                        err = do_md_stop(mddev, 2, 0);
3769                } else
3770                        err = 0; /* already inactive */
3771                break;
3772        case suspended:
3773                break; /* not supported yet */
3774        case readonly:
3775                if (mddev->pers)
3776                        err = md_set_readonly(mddev, 0);
3777                else {
3778                        mddev->ro = 1;
3779                        set_disk_ro(mddev->gendisk, 1);
3780                        err = do_md_run(mddev);
3781                }
3782                break;
3783        case read_auto:
3784                if (mddev->pers) {
3785                        if (mddev->ro == 0)
3786                                err = md_set_readonly(mddev, 0);
3787                        else if (mddev->ro == 1)
3788                                err = restart_array(mddev);
3789                        if (err == 0) {
3790                                mddev->ro = 2;
3791                                set_disk_ro(mddev->gendisk, 0);
3792                        }
3793                } else {
3794                        mddev->ro = 2;
3795                        err = do_md_run(mddev);
3796                }
3797                break;
3798        case clean:
3799                if (mddev->pers) {
3800                        restart_array(mddev);
3801                        spin_lock_irq(&mddev->write_lock);
3802                        if (atomic_read(&mddev->writes_pending) == 0) {
3803                                if (mddev->in_sync == 0) {
3804                                        mddev->in_sync = 1;
3805                                        if (mddev->safemode == 1)
3806                                                mddev->safemode = 0;
3807                                        set_bit(MD_CHANGE_CLEAN, &mddev->flags);
3808                                }
3809                                err = 0;
3810                        } else
3811                                err = -EBUSY;
3812                        spin_unlock_irq(&mddev->write_lock);
3813                } else
3814                        err = -EINVAL;
3815                break;
3816        case active:
3817                if (mddev->pers) {
3818                        restart_array(mddev);
3819                        clear_bit(MD_CHANGE_PENDING, &mddev->flags);
3820                        wake_up(&mddev->sb_wait);
3821                        err = 0;
3822                } else {
3823                        mddev->ro = 0;
3824                        set_disk_ro(mddev->gendisk, 0);
3825                        err = do_md_run(mddev);
3826                }
3827                break;
3828        case write_pending:
3829        case active_idle:
3830                /* these cannot be set */
3831                break;
3832        }
3833        if (err)
3834                return err;
3835        else {
3836                if (mddev->hold_active == UNTIL_IOCTL)
3837                        mddev->hold_active = 0;
3838                sysfs_notify_dirent_safe(mddev->sysfs_state);
3839                return len;
3840        }
3841}
3842static struct md_sysfs_entry md_array_state =
3843__ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
3844
3845static ssize_t
3846max_corrected_read_errors_show(struct mddev *mddev, char *page) {
3847        return sprintf(page, "%d\n",
3848                       atomic_read(&mddev->max_corr_read_errors));
3849}
3850
3851static ssize_t
3852max_corrected_read_errors_store(struct mddev *mddev, const char *buf, size_t len)
3853{
3854        char *e;
3855        unsigned long n = simple_strtoul(buf, &e, 10);
3856
3857        if (*buf && (*e == 0 || *e == '\n')) {
3858                atomic_set(&mddev->max_corr_read_errors, n);
3859                return len;
3860        }
3861        return -EINVAL;
3862}
3863
3864static struct md_sysfs_entry max_corr_read_errors =
3865__ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show,
3866        max_corrected_read_errors_store);
3867
3868static ssize_t
3869null_show(struct mddev *mddev, char *page)
3870{
3871        return -EINVAL;
3872}
3873
3874static ssize_t
3875new_dev_store(struct mddev *mddev, const char *buf, size_t len)
3876{
3877        /* buf must be %d:%d\n? giving major and minor numbers */
3878        /* The new device is added to the array.
3879         * If the array has a persistent superblock, we read the
3880         * superblock to initialise info and check validity.
3881         * Otherwise, only checking done is that in bind_rdev_to_array,
3882         * which mainly checks size.
3883         */
3884        char *e;
3885        int major = simple_strtoul(buf, &e, 10);
3886        int minor;
3887        dev_t dev;
3888        struct md_rdev *rdev;
3889        int err;
3890
3891        if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
3892                return -EINVAL;
3893        minor = simple_strtoul(e+1, &e, 10);
3894        if (*e && *e != '\n')
3895                return -EINVAL;
3896        dev = MKDEV(major, minor);
3897        if (major != MAJOR(dev) ||
3898            minor != MINOR(dev))
3899                return -EOVERFLOW;
3900
3901
3902        if (mddev->persistent) {
3903                rdev = md_import_device(dev, mddev->major_version,
3904                                        mddev->minor_version);
3905                if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
3906                        struct md_rdev *rdev0
3907                                = list_entry(mddev->disks.next,
3908                                             struct md_rdev, same_set);
3909                        err = super_types[mddev->major_version]
3910                                .load_super(rdev, rdev0, mddev->minor_version);
3911                        if (err < 0)
3912                                goto out;
3913                }
3914        } else if (mddev->external)
3915                rdev = md_import_device(dev, -2, -1);
3916        else
3917                rdev = md_import_device(dev, -1, -1);
3918
3919        if (IS_ERR(rdev))
3920                return PTR_ERR(rdev);
3921        err = bind_rdev_to_array(rdev, mddev);
3922 out:
3923        if (err)
3924                export_rdev(rdev);
3925        return err ? err : len;
3926}
3927
3928static struct md_sysfs_entry md_new_device =
3929__ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
3930
3931static ssize_t
3932bitmap_store(struct mddev *mddev, const char *buf, size_t len)
3933{
3934        char *end;
3935        unsigned long chunk, end_chunk;
3936
3937        if (!mddev->bitmap)
3938                goto out;
3939        /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
3940        while (*buf) {
3941                chunk = end_chunk = simple_strtoul(buf, &end, 0);
3942                if (buf == end) break;
3943                if (*end == '-') { /* range */
3944                        buf = end + 1;
3945                        end_chunk = simple_strtoul(buf, &end, 0);
3946                        if (buf == end) break;
3947                }
3948                if (*end && !isspace(*end)) break;
3949                bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
3950                buf = skip_spaces(end);
3951        }
3952        bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
3953out:
3954        return len;
3955}
3956
3957static struct md_sysfs_entry md_bitmap =
3958__ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
3959
3960static ssize_t
3961size_show(struct mddev *mddev, char *page)
3962{
3963        return sprintf(page, "%llu\n",
3964                (unsigned long long)mddev->dev_sectors / 2);
3965}
3966
3967static int update_size(struct mddev *mddev, sector_t num_sectors);
3968
3969static ssize_t
3970size_store(struct mddev *mddev, const char *buf, size_t len)
3971{
3972        /* If array is inactive, we can reduce the component size, but
3973         * not increase it (except from 0).
3974         * If array is active, we can try an on-line resize
3975         */
3976        sector_t sectors;
3977        int err = strict_blocks_to_sectors(buf, &sectors);
3978
3979        if (err < 0)
3980                return err;
3981        if (mddev->pers) {
3982                err = update_size(mddev, sectors);
3983                md_update_sb(mddev, 1);
3984        } else {
3985                if (mddev->dev_sectors == 0 ||
3986                    mddev->dev_sectors > sectors)
3987                        mddev->dev_sectors = sectors;
3988                else
3989                        err = -ENOSPC;
3990        }
3991        return err ? err : len;
3992}
3993
3994static struct md_sysfs_entry md_size =
3995__ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
3996
3997
3998/* Metdata version.
3999 * This is one of
4000 *   'none' for arrays with no metadata (good luck...)
4001 *   'external' for arrays with externally managed metadata,
4002 * or N.M for internally known formats
4003 */
4004static ssize_t
4005metadata_show(struct mddev *mddev, char *page)
4006{
4007        if (mddev->persistent)
4008                return sprintf(page, "%d.%d\n",
4009                               mddev->major_version, mddev->minor_version);
4010        else if (mddev->external)
4011                return sprintf(page, "external:%s\n", mddev->metadata_type);
4012        else
4013                return sprintf(page, "none\n");
4014}
4015
4016static ssize_t
4017metadata_store(struct mddev *mddev, const char *buf, size_t len)
4018{
4019        int major, minor;
4020        char *e;
4021        /* Changing the details of 'external' metadata is
4022         * always permitted.  Otherwise there must be
4023         * no devices attached to the array.
4024         */
4025        if (mddev->external && strncmp(buf, "external:", 9) == 0)
4026                ;
4027        else if (!list_empty(&mddev->disks))
4028                return -EBUSY;
4029
4030        if (cmd_match(buf, "none")) {
4031                mddev->persistent = 0;
4032                mddev->external = 0;
4033                mddev->major_version = 0;
4034                mddev->minor_version = 90;
4035                return len;
4036        }
4037        if (strncmp(buf, "external:", 9) == 0) {
4038                size_t namelen = len-9;
4039                if (namelen >= sizeof(mddev->metadata_type))
4040                        namelen = sizeof(mddev->metadata_type)-1;
4041                strncpy(mddev->metadata_type, buf+9, namelen);
4042                mddev->metadata_type[namelen] = 0;
4043                if (namelen && mddev->metadata_type[namelen-1] == '\n')
4044                        mddev->metadata_type[--namelen] = 0;
4045                mddev->persistent = 0;
4046                mddev->external = 1;
4047                mddev->major_version = 0;
4048                mddev->minor_version = 90;
4049                return len;
4050        }
4051        major = simple_strtoul(buf, &e, 10);
4052        if (e==buf || *e != '.')
4053                return -EINVAL;
4054        buf = e+1;
4055        minor = simple_strtoul(buf, &e, 10);
4056        if (e==buf || (*e && *e != '\n') )
4057                return -EINVAL;
4058        if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
4059                return -ENOENT;
4060        mddev->major_version = major;
4061        mddev->minor_version = minor;
4062        mddev->persistent = 1;
4063        mddev->external = 0;
4064        return len;
4065}
4066
4067static struct md_sysfs_entry md_metadata =
4068__ATTR(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
4069
4070static ssize_t
4071action_show(struct mddev *mddev, char *page)
4072{
4073        char *type = "idle";
4074        if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
4075                type = "frozen";
4076        else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4077            (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) {
4078                if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
4079                        type = "reshape";
4080                else if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
4081                        if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
4082                                type = "resync";
4083                        else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
4084                                type = "check";
4085                        else
4086                                type = "repair";
4087                } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
4088                        type = "recover";
4089        }
4090        return sprintf(page, "%s\n", type);
4091}
4092
4093static void reap_sync_thread(struct mddev *mddev);
4094
4095static ssize_t
4096action_store(struct mddev *mddev, const char *page, size_t len)
4097{
4098        if (!mddev->pers || !mddev->pers->sync_request)
4099                return -EINVAL;
4100
4101        if (cmd_match(page, "frozen"))
4102                set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4103        else
4104                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4105
4106        if (cmd_match(page, "idle") || cmd_match(page, "frozen")) {
4107                if (mddev->sync_thread) {
4108                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4109                        reap_sync_thread(mddev);
4110                }
4111        } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
4112                   test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
4113                return -EBUSY;
4114        else if (cmd_match(page, "resync"))
4115                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4116        else if (cmd_match(page, "recover")) {
4117                set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4118                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4119        } else if (cmd_match(page, "reshape")) {
4120                int err;
4121                if (mddev->pers->start_reshape == NULL)
4122                        return -EINVAL;
4123                err = mddev->pers->start_reshape(mddev);
4124                if (err)
4125                        return err;
4126                sysfs_notify(&mddev->kobj, NULL, "degraded");
4127        } else {
4128                if (cmd_match(page, "check"))
4129                        set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4130                else if (!cmd_match(page, "repair"))
4131                        return -EINVAL;
4132                set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4133                set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4134        }
4135        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4136        md_wakeup_thread(mddev->thread);
4137        sysfs_notify_dirent_safe(mddev->sysfs_action);
4138        return len;
4139}
4140
4141static ssize_t
4142mismatch_cnt_show(struct mddev *mddev, char *page)
4143{
4144        return sprintf(page, "%llu\n",
4145                       (unsigned long long) mddev->resync_mismatches);
4146}
4147
4148static struct md_sysfs_entry md_scan_mode =
4149__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
4150
4151
4152static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
4153
4154static ssize_t
4155sync_min_show(struct mddev *mddev, char *page)
4156{
4157        return sprintf(page, "%d (%s)\n", speed_min(mddev),
4158                       mddev->sync_speed_min ? "local": "system");
4159}
4160
4161static ssize_t
4162sync_min_store(struct mddev *mddev, const char *buf, size_t len)
4163{
4164        int min;
4165        char *e;
4166        if (strncmp(buf, "system", 6)==0) {
4167                mddev->sync_speed_min = 0;
4168                return len;
4169        }
4170        min = simple_strtoul(buf, &e, 10);
4171        if (buf == e || (*e && *e != '\n') || min <= 0)
4172                return -EINVAL;
4173        mddev->sync_speed_min = min;
4174        return len;
4175}
4176
4177static struct md_sysfs_entry md_sync_min =
4178__ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
4179
4180static ssize_t
4181sync_max_show(struct mddev *mddev, char *page)
4182{
4183        return sprintf(page, "%d (%s)\n", speed_max(mddev),
4184                       mddev->sync_speed_max ? "local": "system");
4185}
4186
4187static ssize_t
4188sync_max_store(struct mddev *mddev, const char *buf, size_t len)
4189{
4190        int max;
4191        char *e;
4192        if (strncmp(buf, "system", 6)==0) {
4193                mddev->sync_speed_max = 0;
4194                return len;
4195        }
4196        max = simple_strtoul(buf, &e, 10);
4197        if (buf == e || (*e && *e != '\n') || max <= 0)
4198                return -EINVAL;
4199        mddev->sync_speed_max = max;
4200        return len;
4201}
4202
4203static struct md_sysfs_entry md_sync_max =
4204__ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
4205
4206static ssize_t
4207degraded_show(struct mddev *mddev, char *page)
4208{
4209        return sprintf(page, "%d\n", mddev->degraded);
4210}
4211static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
4212
4213static ssize_t
4214sync_force_parallel_show(struct mddev *mddev, char *page)
4215{
4216        return sprintf(page, "%d\n", mddev->parallel_resync);
4217}
4218
4219static ssize_t
4220sync_force_parallel_store(struct mddev *mddev, const char *buf, size_t len)
4221{
4222        long n;
4223
4224        if (strict_strtol(buf, 10, &n))
4225                return -EINVAL;
4226
4227        if (n != 0 && n != 1)
4228                return -EINVAL;
4229
4230        mddev->parallel_resync = n;
4231
4232        if (mddev->sync_thread)
4233                wake_up(&resync_wait);
4234
4235        return len;
4236}
4237
4238/* force parallel resync, even with shared block devices */
4239static struct md_sysfs_entry md_sync_force_parallel =
4240__ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
4241       sync_force_parallel_show, sync_force_parallel_store);
4242
4243static ssize_t
4244sync_speed_show(struct mddev *mddev, char *page)
4245{
4246        unsigned long resync, dt, db;
4247        if (mddev->curr_resync == 0)
4248                return sprintf(page, "none\n");
4249        resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
4250        dt = (jiffies - mddev->resync_mark) / HZ;
4251        if (!dt) dt++;
4252        db = resync - mddev->resync_mark_cnt;
4253        return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
4254}
4255
4256static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
4257
4258static ssize_t
4259sync_completed_show(struct mddev *mddev, char *page)
4260{
4261        unsigned long long max_sectors, resync;
4262
4263        if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4264                return sprintf(page, "none\n");
4265
4266        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
4267                max_sectors = mddev->resync_max_sectors;
4268        else
4269                max_sectors = mddev->dev_sectors;
4270
4271        resync = mddev->curr_resync_completed;
4272        return sprintf(page, "%llu / %llu\n", resync, max_sectors);
4273}
4274
4275static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
4276
4277static ssize_t
4278min_sync_show(struct mddev *mddev, char *page)
4279{
4280        return sprintf(page, "%llu\n",
4281                       (unsigned long long)mddev->resync_min);
4282}
4283static ssize_t
4284min_sync_store(struct mddev *mddev, const char *buf, size_t len)
4285{
4286        unsigned long long min;
4287        if (strict_strtoull(buf, 10, &min))
4288                return -EINVAL;
4289        if (min > mddev->resync_max)
4290                return -EINVAL;
4291        if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4292                return -EBUSY;
4293
4294        /* Must be a multiple of chunk_size */
4295        if (mddev->chunk_sectors) {
4296                sector_t temp = min;
4297                if (sector_div(temp, mddev->chunk_sectors))
4298                        return -EINVAL;
4299        }
4300        mddev->resync_min = min;
4301
4302        return len;
4303}
4304
4305static struct md_sysfs_entry md_min_sync =
4306__ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
4307
4308static ssize_t
4309max_sync_show(struct mddev *mddev, char *page)
4310{
4311        if (mddev->resync_max == MaxSector)
4312                return sprintf(page, "max\n");
4313        else
4314                return sprintf(page, "%llu\n",
4315                               (unsigned long long)mddev->resync_max);
4316}
4317static ssize_t
4318max_sync_store(struct mddev *mddev, const char *buf, size_t len)
4319{
4320        if (strncmp(buf, "max", 3) == 0)
4321                mddev->resync_max = MaxSector;
4322        else {
4323                unsigned long long max;
4324                if (strict_strtoull(buf, 10, &max))
4325                        return -EINVAL;
4326                if (max < mddev->resync_min)
4327                        return -EINVAL;
4328                if (max < mddev->resync_max &&
4329                    mddev->ro == 0 &&
4330                    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4331                        return -EBUSY;
4332
4333                /* Must be a multiple of chunk_size */
4334                if (mddev->chunk_sectors) {
4335                        sector_t temp = max;
4336                        if (sector_div(temp, mddev->chunk_sectors))
4337                                return -EINVAL;
4338                }
4339                mddev->resync_max = max;
4340        }
4341        wake_up(&mddev->recovery_wait);
4342        return len;
4343}
4344
4345static struct md_sysfs_entry md_max_sync =
4346__ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
4347
4348static ssize_t
4349suspend_lo_show(struct mddev *mddev, char *page)
4350{
4351        return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
4352}
4353
4354static ssize_t
4355suspend_lo_store(struct mddev *mddev, const char *buf, size_t len)
4356{
4357        char *e;
4358        unsigned long long new = simple_strtoull(buf, &e, 10);
4359        unsigned long long old = mddev->suspend_lo;
4360
4361        if (mddev->pers == NULL || 
4362            mddev->pers->quiesce == NULL)
4363                return -EINVAL;
4364        if (buf == e || (*e && *e != '\n'))
4365                return -EINVAL;
4366
4367        mddev->suspend_lo = new;
4368        if (new >= old)
4369                /* Shrinking suspended region */
4370                mddev->pers->quiesce(mddev, 2);
4371        else {
4372                /* Expanding suspended region - need to wait */
4373                mddev->pers->quiesce(mddev, 1);
4374                mddev->pers->quiesce(mddev, 0);
4375        }
4376        return len;
4377}
4378static struct md_sysfs_entry md_suspend_lo =
4379__ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
4380
4381
4382static ssize_t
4383suspend_hi_show(struct mddev *mddev, char *page)
4384{
4385        return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
4386}
4387
4388static ssize_t
4389suspend_hi_store(struct mddev *mddev, const char *buf, size_t len)
4390{
4391        char *e;
4392        unsigned long long new = simple_strtoull(buf, &e, 10);
4393        unsigned long long old = mddev->suspend_hi;
4394
4395        if (mddev->pers == NULL ||
4396            mddev->pers->quiesce == NULL)
4397                return -EINVAL;
4398        if (buf == e || (*e && *e != '\n'))
4399                return -EINVAL;
4400
4401        mddev->suspend_hi = new;
4402        if (new <= old)
4403                /* Shrinking suspended region */
4404                mddev->pers->quiesce(mddev, 2);
4405        else {
4406                /* Expanding suspended region - need to wait */
4407                mddev->pers->quiesce(mddev, 1);
4408                mddev->pers->quiesce(mddev, 0);
4409        }
4410        return len;
4411}
4412static struct md_sysfs_entry md_suspend_hi =
4413__ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
4414
4415static ssize_t
4416reshape_position_show(struct mddev *mddev, char *page)
4417{
4418        if (mddev->reshape_position != MaxSector)
4419                return sprintf(page, "%llu\n",
4420                               (unsigned long long)mddev->reshape_position);
4421        strcpy(page, "none\n");
4422        return 5;
4423}
4424
4425static ssize_t
4426reshape_position_store(struct mddev *mddev, const char *buf, size_t len)
4427{
4428        char *e;
4429        unsigned long long new = simple_strtoull(buf, &e, 10);
4430        if (mddev->pers)
4431                return -EBUSY;
4432        if (buf == e || (*e && *e != '\n'))
4433                return -EINVAL;
4434        mddev->reshape_position = new;
4435        mddev->delta_disks = 0;
4436        mddev->new_level = mddev->level;
4437        mddev->new_layout = mddev->layout;
4438        mddev->new_chunk_sectors = mddev->chunk_sectors;
4439        return len;
4440}
4441
4442static struct md_sysfs_entry md_reshape_position =
4443__ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
4444       reshape_position_store);
4445
4446static ssize_t
4447array_size_show(struct mddev *mddev, char *page)
4448{
4449        if (mddev->external_size)
4450                return sprintf(page, "%llu\n",
4451                               (unsigned long long)mddev->array_sectors/2);
4452        else
4453                return sprintf(page, "default\n");
4454}
4455
4456static ssize_t
4457array_size_store(struct mddev *mddev, const char *buf, size_t len)
4458{
4459        sector_t sectors;
4460
4461        if (strncmp(buf, "default", 7) == 0) {
4462                if (mddev->pers)
4463                        sectors = mddev->pers->size(mddev, 0, 0);
4464                else
4465                        sectors = mddev->array_sectors;
4466
4467                mddev->external_size = 0;
4468        } else {
4469                if (strict_blocks_to_sectors(buf, &sectors) < 0)
4470                        return -EINVAL;
4471                if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
4472                        return -E2BIG;
4473
4474                mddev->external_size = 1;
4475        }
4476
4477        mddev->array_sectors = sectors;
4478        if (mddev->pers) {
4479                set_capacity(mddev->gendisk, mddev->array_sectors);
4480                revalidate_disk(mddev->gendisk);
4481        }
4482        return len;
4483}
4484
4485static struct md_sysfs_entry md_array_size =
4486__ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
4487       array_size_store);
4488
4489static struct attribute *md_default_attrs[] = {
4490        &md_level.attr,
4491        &md_layout.attr,
4492        &md_raid_disks.attr,
4493        &md_chunk_size.attr,
4494        &md_size.attr,
4495        &md_resync_start.attr,
4496        &md_metadata.attr,
4497        &md_new_device.attr,
4498        &md_safe_delay.attr,
4499        &md_array_state.attr,
4500        &md_reshape_position.attr,
4501        &md_array_size.attr,
4502        &max_corr_read_errors.attr,
4503        NULL,
4504};
4505
4506static struct attribute *md_redundancy_attrs[] = {
4507        &md_scan_mode.attr,
4508        &md_mismatches.attr,
4509        &md_sync_min.attr,
4510        &md_sync_max.attr,
4511        &md_sync_speed.attr,
4512        &md_sync_force_parallel.attr,
4513        &md_sync_completed.attr,
4514        &md_min_sync.attr,
4515        &md_max_sync.attr,
4516        &md_suspend_lo.attr,
4517        &md_suspend_hi.attr,
4518        &md_bitmap.attr,
4519        &md_degraded.attr,
4520        NULL,
4521};
4522static struct attribute_group md_redundancy_group = {
4523        .name = NULL,
4524        .attrs = md_redundancy_attrs,
4525};
4526
4527
4528static ssize_t
4529md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
4530{
4531        struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4532        struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4533        ssize_t rv;
4534
4535        if (!entry->show)
4536                return -EIO;
4537        spin_lock(&all_mddevs_lock);
4538        if (list_empty(&mddev->all_mddevs)) {
4539                spin_unlock(&all_mddevs_lock);
4540                return -EBUSY;
4541        }
4542        mddev_get(mddev);
4543        spin_unlock(&all_mddevs_lock);
4544
4545        rv = mddev_lock(mddev);
4546        if (!rv) {
4547                rv = entry->show(mddev, page);
4548                mddev_unlock(mddev);
4549        }
4550        mddev_put(mddev);
4551        return rv;
4552}
4553
4554static ssize_t
4555md_attr_store(struct kobject *kobj, struct attribute *attr,
4556              const char *page, size_t length)
4557{
4558        struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
4559        struct mddev *mddev = container_of(kobj, struct mddev, kobj);
4560        ssize_t rv;
4561
4562        if (!entry->store)
4563                return -EIO;
4564        if (!capable(CAP_SYS_ADMIN))
4565                return -EACCES;
4566        spin_lock(&all_mddevs_lock);
4567        if (list_empty(&mddev->all_mddevs)) {
4568                spin_unlock(&all_mddevs_lock);
4569                return -EBUSY;
4570        }
4571        mddev_get(mddev);
4572        spin_unlock(&all_mddevs_lock);
4573        rv = mddev_lock(mddev);
4574        if (!rv) {
4575                rv = entry->store(mddev, page, length);
4576                mddev_unlock(mddev);
4577        }
4578        mddev_put(mddev);
4579        return rv;
4580}
4581
4582static void md_free(struct kobject *ko)
4583{
4584        struct mddev *mddev = container_of(ko, struct mddev, kobj);
4585
4586        if (mddev->sysfs_state)
4587                sysfs_put(mddev->sysfs_state);
4588
4589        if (mddev->gendisk) {
4590                del_gendisk(mddev->gendisk);
4591                put_disk(mddev->gendisk);
4592        }
4593        if (mddev->queue)
4594                blk_cleanup_queue(mddev->queue);
4595
4596        kfree(mddev);
4597}
4598
4599static const struct sysfs_ops md_sysfs_ops = {
4600        .show   = md_attr_show,
4601        .store  = md_attr_store,
4602};
4603static struct kobj_type md_ktype = {
4604        .release        = md_free,
4605        .sysfs_ops      = &md_sysfs_ops,
4606        .default_attrs  = md_default_attrs,
4607};
4608
4609int mdp_major = 0;
4610
4611static void mddev_delayed_delete(struct work_struct *ws)
4612{
4613        struct mddev *mddev = container_of(ws, struct mddev, del_work);
4614
4615        sysfs_remove_group(&mddev->kobj, &md_bitmap_group);
4616        kobject_del(&mddev->kobj);
4617        kobject_put(&mddev->kobj);
4618}
4619
4620static int md_alloc(dev_t dev, char *name)
4621{
4622        static DEFINE_MUTEX(disks_mutex);
4623        struct mddev *mddev = mddev_find(dev);
4624        struct gendisk *disk;
4625        int partitioned;
4626        int shift;
4627        int unit;
4628        int error;
4629
4630        if (!mddev)
4631                return -ENODEV;
4632
4633        partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
4634        shift = partitioned ? MdpMinorShift : 0;
4635        unit = MINOR(mddev->unit) >> shift;
4636
4637        /* wait for any previous instance of this device to be
4638         * completely removed (mddev_delayed_delete).
4639         */
4640        flush_workqueue(md_misc_wq);
4641
4642        mutex_lock(&disks_mutex);
4643        error = -EEXIST;
4644        if (mddev->gendisk)
4645                goto abort;
4646
4647        if (name) {
4648                /* Need to ensure that 'name' is not a duplicate.
4649                 */
4650                struct mddev *mddev2;
4651                spin_lock(&all_mddevs_lock);
4652
4653                list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
4654                        if (mddev2->gendisk &&
4655                            strcmp(mddev2->gendisk->disk_name, name) == 0) {
4656                                spin_unlock(&all_mddevs_lock);
4657                                goto abort;
4658                        }
4659                spin_unlock(&all_mddevs_lock);
4660        }
4661
4662        error = -ENOMEM;
4663        mddev->queue = blk_alloc_queue(GFP_KERNEL);
4664        if (!mddev->queue)
4665                goto abort;
4666        mddev->queue->queuedata = mddev;
4667
4668        blk_queue_make_request(mddev->queue, md_make_request);
4669        blk_set_stacking_limits(&mddev->queue->limits);
4670
4671        disk = alloc_disk(1 << shift);
4672        if (!disk) {
4673                blk_cleanup_queue(mddev->queue);
4674                mddev->queue = NULL;
4675                goto abort;
4676        }
4677        disk->major = MAJOR(mddev->unit);
4678        disk->first_minor = unit << shift;
4679        if (name)
4680                strcpy(disk->disk_name, name);
4681        else if (partitioned)
4682                sprintf(disk->disk_name, "md_d%d", unit);
4683        else
4684                sprintf(disk->disk_name, "md%d", unit);
4685        disk->fops = &md_fops;
4686        disk->private_data = mddev;
4687        disk->queue = mddev->queue;
4688        blk_queue_flush(mddev->queue, REQ_FLUSH | REQ_FUA);
4689        /* Allow extended partitions.  This makes the
4690         * 'mdp' device redundant, but we can't really
4691         * remove it now.
4692         */
4693        disk->flags |= GENHD_FL_EXT_DEVT;
4694        mddev->gendisk = disk;
4695        /* As soon as we call add_disk(), another thread could get
4696         * through to md_open, so make sure it doesn't get too far
4697         */
4698        mutex_lock(&mddev->open_mutex);
4699        add_disk(disk);
4700
4701        error = kobject_init_and_add(&mddev->kobj, &md_ktype,
4702                                     &disk_to_dev(disk)->kobj, "%s", "md");
4703        if (error) {
4704                /* This isn't possible, but as kobject_init_and_add is marked
4705                 * __must_check, we must do something with the result
4706                 */
4707                printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
4708                       disk->disk_name);
4709                error = 0;
4710        }
4711        if (mddev->kobj.sd &&
4712            sysfs_create_group(&mddev->kobj, &md_bitmap_group))
4713                printk(KERN_DEBUG "pointless warning\n");
4714        mutex_unlock(&mddev->open_mutex);
4715 abort:
4716        mutex_unlock(&disks_mutex);
4717        if (!error && mddev->kobj.sd) {
4718                kobject_uevent(&mddev->kobj, KOBJ_ADD);
4719                mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
4720        }
4721        mddev_put(mddev);
4722        return error;
4723}
4724
4725static struct kobject *md_probe(dev_t dev, int *part, void *data)
4726{
4727        md_alloc(dev, NULL);
4728        return NULL;
4729}
4730
4731static int add_named_array(const char *val, struct kernel_param *kp)
4732{
4733        /* val must be "md_*" where * is not all digits.
4734         * We allocate an array with a large free minor number, and
4735         * set the name to val.  val must not already be an active name.
4736         */
4737        int len = strlen(val);
4738        char buf[DISK_NAME_LEN];
4739
4740        while (len && val[len-1] == '\n')
4741                len--;
4742        if (len >= DISK_NAME_LEN)
4743                return -E2BIG;
4744        strlcpy(buf, val, len+1);
4745        if (strncmp(buf, "md_", 3) != 0)
4746                return -EINVAL;
4747        return md_alloc(0, buf);
4748}
4749
4750static void md_safemode_timeout(unsigned long data)
4751{
4752        struct mddev *mddev = (struct mddev *) data;
4753
4754        if (!atomic_read(&mddev->writes_pending)) {
4755                mddev->safemode = 1;
4756                if (mddev->external)
4757                        sysfs_notify_dirent_safe(mddev->sysfs_state);
4758        }
4759        md_wakeup_thread(mddev->thread);
4760}
4761
4762static int start_dirty_degraded;
4763
4764int md_run(struct mddev *mddev)
4765{
4766        int err;
4767        struct md_rdev *rdev;
4768        struct md_personality *pers;
4769
4770        if (list_empty(&mddev->disks))
4771                /* cannot run an array with no devices.. */
4772                return -EINVAL;
4773
4774        if (mddev->pers)
4775                return -EBUSY;
4776        /* Cannot run until previous stop completes properly */
4777        if (mddev->sysfs_active)
4778                return -EBUSY;
4779
4780        /*
4781         * Analyze all RAID superblock(s)
4782         */
4783        if (!mddev->raid_disks) {
4784                if (!mddev->persistent)
4785                        return -EINVAL;
4786                analyze_sbs(mddev);
4787        }
4788
4789        if (mddev->level != LEVEL_NONE)
4790                request_module("md-level-%d", mddev->level);
4791        else if (mddev->clevel[0])
4792                request_module("md-%s", mddev->clevel);
4793
4794        /*
4795         * Drop all container device buffers, from now on
4796         * the only valid external interface is through the md
4797         * device.
4798         */
4799        list_for_each_entry(rdev, &mddev->disks, same_set) {
4800                if (test_bit(Faulty, &rdev->flags))
4801                        continue;
4802                sync_blockdev(rdev->bdev);
4803                invalidate_bdev(rdev->bdev);
4804
4805                /* perform some consistency tests on the device.
4806                 * We don't want the data to overlap the metadata,
4807                 * Internal Bitmap issues have been handled elsewhere.
4808                 */
4809                if (rdev->meta_bdev) {
4810                        /* Nothing to check */;
4811                } else if (rdev->data_offset < rdev->sb_start) {
4812                        if (mddev->dev_sectors &&
4813                            rdev->data_offset + mddev->dev_sectors
4814                            > rdev->sb_start) {
4815                                printk("md: %s: data overlaps metadata\n",
4816                                       mdname(mddev));
4817                                return -EINVAL;
4818                        }
4819                } else {
4820                        if (rdev->sb_start + rdev->sb_size/512
4821                            > rdev->data_offset) {
4822                                printk("md: %s: metadata overlaps data\n",
4823                                       mdname(mddev));
4824                                return -EINVAL;
4825                        }
4826                }
4827                sysfs_notify_dirent_safe(rdev->sysfs_state);
4828        }
4829
4830        if (mddev->bio_set == NULL)
4831                mddev->bio_set = bioset_create(BIO_POOL_SIZE,
4832                                               sizeof(struct mddev *));
4833
4834        spin_lock(&pers_lock);
4835        pers = find_pers(mddev->level, mddev->clevel);
4836        if (!pers || !try_module_get(pers->owner)) {
4837                spin_unlock(&pers_lock);
4838                if (mddev->level != LEVEL_NONE)
4839                        printk(KERN_WARNING "md: personality for level %d is not loaded!\n",
4840                               mddev->level);
4841                else
4842                        printk(KERN_WARNING "md: personality for level %s is not loaded!\n",
4843                               mddev->clevel);
4844                return -EINVAL;
4845        }
4846        mddev->pers = pers;
4847        spin_unlock(&pers_lock);
4848        if (mddev->level != pers->level) {
4849                mddev->level = pers->level;
4850                mddev->new_level = pers->level;
4851        }
4852        strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
4853
4854        if (mddev->reshape_position != MaxSector &&
4855            pers->start_reshape == NULL) {
4856                /* This personality cannot handle reshaping... */
4857                mddev->pers = NULL;
4858                module_put(pers->owner);
4859                return -EINVAL;
4860        }
4861
4862        if (pers->sync_request) {
4863                /* Warn if this is a potentially silly
4864                 * configuration.
4865                 */
4866                char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
4867                struct md_rdev *rdev2;
4868                int warned = 0;
4869
4870                list_for_each_entry(rdev, &mddev->disks, same_set)
4871                        list_for_each_entry(rdev2, &mddev->disks, same_set) {
4872                                if (rdev < rdev2 &&
4873                                    rdev->bdev->bd_contains ==
4874                                    rdev2->bdev->bd_contains) {
4875                                        printk(KERN_WARNING
4876                                               "%s: WARNING: %s appears to be"
4877                                               " on the same physical disk as"
4878                                               " %s.\n",
4879                                               mdname(mddev),
4880                                               bdevname(rdev->bdev,b),
4881                                               bdevname(rdev2->bdev,b2));
4882                                        warned = 1;
4883                                }
4884                        }
4885
4886                if (warned)
4887                        printk(KERN_WARNING
4888                               "True protection against single-disk"
4889                               " failure might be compromised.\n");
4890        }
4891
4892        mddev->recovery = 0;
4893        /* may be over-ridden by personality */
4894        mddev->resync_max_sectors = mddev->dev_sectors;
4895
4896        mddev->ok_start_degraded = start_dirty_degraded;
4897
4898        if (start_readonly && mddev->ro == 0)
4899                mddev->ro = 2; /* read-only, but switch on first write */
4900
4901        err = mddev->pers->run(mddev);
4902        if (err)
4903                printk(KERN_ERR "md: pers->run() failed ...\n");
4904        else if (mddev->pers->size(mddev, 0, 0) < mddev->array_sectors) {
4905                WARN_ONCE(!mddev->external_size, "%s: default size too small,"
4906                          " but 'external_size' not in effect?\n", __func__);
4907                printk(KERN_ERR
4908                       "md: invalid array_size %llu > default size %llu\n",
4909                       (unsigned long long)mddev->array_sectors / 2,
4910                       (unsigned long long)mddev->pers->size(mddev, 0, 0) / 2);
4911                err = -EINVAL;
4912                mddev->pers->stop(mddev);
4913        }
4914        if (err == 0 && mddev->pers->sync_request) {
4915                err = bitmap_create(mddev);
4916                if (err) {
4917                        printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
4918                               mdname(mddev), err);
4919                        mddev->pers->stop(mddev);
4920                }
4921        }
4922        if (err) {
4923                module_put(mddev->pers->owner);
4924                mddev->pers = NULL;
4925                bitmap_destroy(mddev);
4926                return err;
4927        }
4928        if (mddev->pers->sync_request) {
4929                if (mddev->kobj.sd &&
4930                    sysfs_create_group(&mddev->kobj, &md_redundancy_group))
4931                        printk(KERN_WARNING
4932                               "md: cannot register extra attributes for %s\n",
4933                               mdname(mddev));
4934                mddev->sysfs_action = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_action");
4935        } else if (mddev->ro == 2) /* auto-readonly not meaningful */
4936                mddev->ro = 0;
4937
4938        atomic_set(&mddev->writes_pending,0);
4939        atomic_set(&mddev->max_corr_read_errors,
4940                   MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
4941        mddev->safemode = 0;
4942        mddev->safemode_timer.function = md_safemode_timeout;
4943        mddev->safemode_timer.data = (unsigned long) mddev;
4944        mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
4945        mddev->in_sync = 1;
4946        smp_wmb();
4947        mddev->ready = 1;
4948        list_for_each_entry(rdev, &mddev->disks, same_set)
4949                if (rdev->raid_disk >= 0)
4950                        if (sysfs_link_rdev(mddev, rdev))
4951                                /* failure here is OK */;
4952        
4953        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4954        
4955        if (mddev->flags)
4956                md_update_sb(mddev, 0);
4957
4958        md_new_event(mddev);
4959        sysfs_notify_dirent_safe(mddev->sysfs_state);
4960        sysfs_notify_dirent_safe(mddev->sysfs_action);
4961        sysfs_notify(&mddev->kobj, NULL, "degraded");
4962        return 0;
4963}
4964EXPORT_SYMBOL_GPL(md_run);
4965
4966static int do_md_run(struct mddev *mddev)
4967{
4968        int err;
4969
4970        err = md_run(mddev);
4971        if (err)
4972                goto out;
4973        err = bitmap_load(mddev);
4974        if (err) {
4975                bitmap_destroy(mddev);
4976                goto out;
4977        }
4978
4979        md_wakeup_thread(mddev->thread);
4980        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
4981
4982        set_capacity(mddev->gendisk, mddev->array_sectors);
4983        revalidate_disk(mddev->gendisk);
4984        mddev->changed = 1;
4985        kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
4986out:
4987        return err;
4988}
4989
4990static int restart_array(struct mddev *mddev)
4991{
4992        struct gendisk *disk = mddev->gendisk;
4993
4994        /* Complain if it has no devices */
4995        if (list_empty(&mddev->disks))
4996                return -ENXIO;
4997        if (!mddev->pers)
4998                return -EINVAL;
4999        if (!mddev->ro)
5000                return -EBUSY;
5001        mddev->safemode = 0;
5002        mddev->ro = 0;
5003        set_disk_ro(disk, 0);
5004        printk(KERN_INFO "md: %s switched to read-write mode.\n",
5005                mdname(mddev));
5006        /* Kick recovery or resync if necessary */
5007        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5008        md_wakeup_thread(mddev->thread);
5009        md_wakeup_thread(mddev->sync_thread);
5010        sysfs_notify_dirent_safe(mddev->sysfs_state);
5011        return 0;
5012}
5013
5014/* similar to deny_write_access, but accounts for our holding a reference
5015 * to the file ourselves */
5016static int deny_bitmap_write_access(struct file * file)
5017{
5018        struct inode *inode = file->f_mapping->host;
5019
5020        spin_lock(&inode->i_lock);
5021        if (atomic_read(&inode->i_writecount) > 1) {
5022                spin_unlock(&inode->i_lock);
5023                return -ETXTBSY;
5024        }
5025        atomic_set(&inode->i_writecount, -1);
5026        spin_unlock(&inode->i_lock);
5027
5028        return 0;
5029}
5030
5031void restore_bitmap_write_access(struct file *file)
5032{
5033        struct inode *inode = file->f_mapping->host;
5034
5035        spin_lock(&inode->i_lock);
5036        atomic_set(&inode->i_writecount, 1);
5037        spin_unlock(&inode->i_lock);
5038}
5039
5040static void md_clean(struct mddev *mddev)
5041{
5042        mddev->array_sectors = 0;
5043        mddev->external_size = 0;
5044        mddev->dev_sectors = 0;
5045        mddev->raid_disks = 0;
5046        mddev->recovery_cp = 0;
5047        mddev->resync_min = 0;
5048        mddev->resync_max = MaxSector;
5049        mddev->reshape_position = MaxSector;
5050        mddev->external = 0;
5051        mddev->persistent = 0;
5052        mddev->level = LEVEL_NONE;
5053        mddev->clevel[0] = 0;
5054        mddev->flags = 0;
5055        mddev->ro = 0;
5056        mddev->metadata_type[0] = 0;
5057        mddev->chunk_sectors = 0;
5058        mddev->ctime = mddev->utime = 0;
5059        mddev->layout = 0;
5060        mddev->max_disks = 0;
5061        mddev->events = 0;
5062        mddev->can_decrease_events = 0;
5063        mddev->delta_disks = 0;
5064        mddev->new_level = LEVEL_NONE;
5065        mddev->new_layout = 0;
5066        mddev->new_chunk_sectors = 0;
5067        mddev->curr_resync = 0;
5068        mddev->resync_mismatches = 0;
5069        mddev->suspend_lo = mddev->suspend_hi = 0;
5070        mddev->sync_speed_min = mddev->sync_speed_max = 0;
5071        mddev->recovery = 0;
5072        mddev->in_sync = 0;
5073        mddev->changed = 0;
5074        mddev->degraded = 0;
5075        mddev->safemode = 0;
5076        mddev->bitmap_info.offset = 0;
5077        mddev->bitmap_info.default_offset = 0;
5078        mddev->bitmap_info.chunksize = 0;
5079        mddev->bitmap_info.daemon_sleep = 0;
5080        mddev->bitmap_info.max_write_behind = 0;
5081}
5082
5083static void __md_stop_writes(struct mddev *mddev)
5084{
5085        if (mddev->sync_thread) {
5086                set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5087                set_bit(MD_RECOVERY_INTR, &mddev->recovery);
5088                reap_sync_thread(mddev);
5089        }
5090
5091        del_timer_sync(&mddev->safemode_timer);
5092
5093        bitmap_flush(mddev);
5094        md_super_wait(mddev);
5095
5096        if (!mddev->in_sync || mddev->flags) {
5097                /* mark array as shutdown cleanly */
5098                mddev->in_sync = 1;
5099                md_update_sb(mddev, 1);
5100        }
5101}
5102
5103void md_stop_writes(struct mddev *mddev)
5104{
5105        mddev_lock(mddev);
5106        __md_stop_writes(mddev);
5107        mddev_unlock(mddev);
5108}
5109EXPORT_SYMBOL_GPL(md_stop_writes);
5110
5111void md_stop(struct mddev *mddev)
5112{
5113        mddev->ready = 0;
5114        mddev->pers->stop(mddev);
5115        if (mddev->pers->sync_request && mddev->to_remove == NULL)
5116                mddev->to_remove = &md_redundancy_group;
5117        module_put(mddev->pers->owner);
5118        mddev->pers = NULL;
5119        clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5120}
5121EXPORT_SYMBOL_GPL(md_stop);
5122
5123static int md_set_readonly(struct mddev *mddev, int is_open)
5124{
5125        int err = 0;
5126        mutex_lock(&mddev->open_mutex);
5127        if (atomic_read(&mddev->openers) > is_open) {
5128                printk("md: %s still in use.\n",mdname(mddev));
5129                err = -EBUSY;
5130                goto out;
5131        }
5132        if (mddev->pers) {
5133                __md_stop_writes(mddev);
5134
5135                err  = -ENXIO;
5136                if (mddev->ro==1)
5137                        goto out;
5138                mddev->ro = 1;
5139                set_disk_ro(mddev->gendisk, 1);
5140                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
5141                sysfs_notify_dirent_safe(mddev->sysfs_state);
5142                err = 0;        
5143        }
5144out:
5145        mutex_unlock(&mddev->open_mutex);
5146        return err;
5147}
5148
5149/* mode:
5150 *   0 - completely stop and dis-assemble array
5151 *   2 - stop but do not disassemble array
5152 */
5153static int do_md_stop(struct mddev * mddev, int mode, int is_open)
5154{
5155        struct gendisk *disk = mddev->gendisk;
5156        struct md_rdev *rdev;
5157
5158        mutex_lock(&mddev->open_mutex);
5159        if (atomic_read(&mddev->openers) > is_open ||
5160            mddev->sysfs_active) {
5161                printk("md: %s still in use.\n",mdname(mddev));
5162                mutex_unlock(&mddev->open_mutex);
5163                return -EBUSY;
5164        }
5165
5166        if (mddev->pers) {
5167                if (mddev->ro)
5168                        set_disk_ro(disk, 0);
5169
5170                __md_stop_writes(mddev);
5171                md_stop(mddev);
5172                mddev->queue->merge_bvec_fn = NULL;
5173                mddev->queue->backing_dev_info.congested_fn = NULL;
5174
5175                /* tell userspace to handle 'inactive' */
5176                sysfs_notify_dirent_safe(mddev->sysfs_state);
5177
5178                list_for_each_entry(rdev, &mddev->disks, same_set)
5179                        if (rdev->raid_disk >= 0)
5180                                sysfs_unlink_rdev(mddev, rdev);
5181
5182                set_capacity(disk, 0);
5183                mutex_unlock(&mddev->open_mutex);
5184                mddev->changed = 1;
5185                revalidate_disk(disk);
5186
5187                if (mddev->ro)
5188                        mddev->ro = 0;
5189        } else
5190                mutex_unlock(&mddev->open_mutex);
5191        /*
5192         * Free resources if final stop
5193         */
5194        if (mode == 0) {
5195                printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
5196
5197                bitmap_destroy(mddev);
5198                if (mddev->bitmap_info.file) {
5199                        restore_bitmap_write_access(mddev->bitmap_info.file);
5200                        fput(mddev->bitmap_info.file);
5201                        mddev->bitmap_info.file = NULL;
5202                }
5203                mddev->bitmap_info.offset = 0;
5204
5205                export_array(mddev);
5206
5207                md_clean(mddev);
5208                kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
5209                if (mddev->hold_active == UNTIL_STOP)
5210                        mddev->hold_active = 0;
5211        }
5212        blk_integrity_unregister(disk);
5213        md_new_event(mddev);
5214        sysfs_notify_dirent_safe(mddev->sysfs_state);
5215        return 0;
5216}
5217
5218#ifndef MODULE
5219static void autorun_array(struct mddev *mddev)
5220{
5221        struct md_rdev *rdev;
5222        int err;
5223
5224        if (list_empty(&mddev->disks))
5225                return;
5226
5227        printk(KERN_INFO "md: running: ");
5228
5229        list_for_each_entry(rdev, &mddev->disks, same_set) {
5230                char b[BDEVNAME_SIZE];
5231                printk("<%s>", bdevname(rdev->bdev,b));
5232        }
5233        printk("\n");
5234
5235        err = do_md_run(mddev);
5236        if (err) {
5237                printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
5238                do_md_stop(mddev, 0, 0);
5239        }
5240}
5241
5242/*
5243 * lets try to run arrays based on all disks that have arrived
5244 * until now. (those are in pending_raid_disks)
5245 *
5246 * the method: pick the first pending disk, collect all disks with
5247 * the same UUID, remove all from the pending list and put them into
5248 * the 'same_array' list. Then order this list based on superblock
5249 * update time (freshest comes first), kick out 'old' disks and
5250 * compare superblocks. If everything's fine then run it.
5251 *
5252 * If "unit" is allocated, then bump its reference count
5253 */
5254static void autorun_devices(int part)
5255{
5256        struct md_rdev *rdev0, *rdev, *tmp;
5257        struct mddev *mddev;
5258        char b[BDEVNAME_SIZE];
5259
5260        printk(KERN_INFO "md: autorun ...\n");
5261        while (!list_empty(&pending_raid_disks)) {
5262                int unit;
5263                dev_t dev;
5264                LIST_HEAD(candidates);
5265                rdev0 = list_entry(pending_raid_disks.next,
5266                                         struct md_rdev, same_set);
5267
5268                printk(KERN_INFO "md: considering %s ...\n",
5269                        bdevname(rdev0->bdev,b));
5270                INIT_LIST_HEAD(&candidates);
5271                rdev_for_each_list(rdev, tmp, &pending_raid_disks)
5272                        if (super_90_load(rdev, rdev0, 0) >= 0) {
5273                                printk(KERN_INFO "md:  adding %s ...\n",
5274                                        bdevname(rdev->bdev,b));
5275                                list_move(&rdev->same_set, &candidates);
5276                        }
5277                /*
5278                 * now we have a set of devices, with all of them having
5279                 * mostly sane superblocks. It's time to allocate the
5280                 * mddev.
5281                 */
5282                if (part) {
5283                        dev = MKDEV(mdp_major,
5284                                    rdev0->preferred_minor << MdpMinorShift);
5285                        unit = MINOR(dev) >> MdpMinorShift;
5286                } else {
5287                        dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
5288                        unit = MINOR(dev);
5289                }
5290                if (rdev0->preferred_minor != unit) {
5291                        printk(KERN_INFO "md: unit number in %s is bad: %d\n",
5292                               bdevname(rdev0->bdev, b), rdev0->preferred_minor);
5293                        break;
5294                }
5295
5296                md_probe(dev, NULL, NULL);
5297                mddev = mddev_find(dev);
5298                if (!mddev || !mddev->gendisk) {
5299                        if (mddev)
5300                                mddev_put(mddev);
5301                        printk(KERN_ERR
5302                                "md: cannot allocate memory for md drive.\n");
5303                        break;
5304                }
5305                if (mddev_lock(mddev)) 
5306                        printk(KERN_WARNING "md: %s locked, cannot run\n",
5307                               mdname(mddev));
5308                else if (mddev->raid_disks || mddev->major_version
5309                         || !list_empty(&mddev->disks)) {
5310                        printk(KERN_WARNING 
5311                                "md: %s already running, cannot run %s\n",
5312                                mdname(mddev), bdevname(rdev0->bdev,b));
5313                        mddev_unlock(mddev);
5314                } else {
5315                        printk(KERN_INFO "md: created %s\n", mdname(mddev));
5316                        mddev->persistent = 1;
5317                        rdev_for_each_list(rdev, tmp, &candidates) {
5318                                list_del_init(&rdev->same_set);
5319                                if (bind_rdev_to_array(rdev, mddev))
5320                                        export_rdev(rdev);
5321                        }
5322                        autorun_array(mddev);
5323                        mddev_unlock(mddev);
5324                }
5325                /* on success, candidates will be empty, on error
5326                 * it won't...
5327                 */
5328                rdev_for_each_list(rdev, tmp, &candidates) {
5329                        list_del_init(&rdev->same_set);
5330                        export_rdev(rdev);
5331                }
5332                mddev_put(mddev);
5333        }
5334        printk(KERN_INFO "md: ... autorun DONE.\n");
5335}
5336#endif /* !MODULE */
5337
5338static int get_version(void __user * arg)
5339{
5340        mdu_version_t ver;
5341
5342        ver.major = MD_MAJOR_VERSION;
5343        ver.minor = MD_MINOR_VERSION;
5344        ver.patchlevel = MD_PATCHLEVEL_VERSION;
5345
5346        if (copy_to_user(arg, &ver, sizeof(ver)))
5347                return -EFAULT;
5348
5349        return 0;
5350}
5351
5352static int get_array_info(struct mddev * mddev, void __user * arg)
5353{
5354        mdu_array_info_t info;
5355        int nr,working,insync,failed,spare;
5356        struct md_rdev *rdev;
5357
5358        nr=working=insync=failed=spare=0;
5359        list_for_each_entry(rdev, &mddev->disks, same_set) {
5360                nr++;
5361                if (test_bit(Faulty, &rdev->flags))
5362                        failed++;
5363                else {
5364                        working++;
5365                        if (test_bit(In_sync, &rdev->flags))
5366                                insync++;       
5367                        else
5368                                spare++;
5369                }
5370        }
5371
5372        info.major_version = mddev->major_version;
5373        info.minor_version = mddev->minor_version;
5374        info.patch_version = MD_PATCHLEVEL_VERSION;
5375        info.ctime         = mddev->ctime;
5376        info.level         = mddev->level;
5377        info.size          = mddev->dev_sectors / 2;
5378        if (info.size != mddev->dev_sectors / 2) /* overflow */
5379                info.size = -1;
5380        info.nr_disks      = nr;
5381        info.raid_disks    = mddev->raid_disks;
5382        info.md_minor      = mddev->md_minor;
5383        info.not_persistent= !mddev->persistent;
5384
5385        info.utime         = mddev->utime;
5386        info.state         = 0;
5387        if (mddev->in_sync)
5388                info.state = (1<<MD_SB_CLEAN);
5389        if (mddev->bitmap && mddev->bitmap_info.offset)
5390                info.state = (1<<MD_SB_BITMAP_PRESENT);
5391        info.active_disks  = insync;
5392        info.working_disks = working;
5393        info.failed_disks  = failed;
5394        info.spare_disks   = spare;
5395
5396        info.layout        = mddev->layout;
5397        info.chunk_size    = mddev->chunk_sectors << 9;
5398
5399        if (copy_to_user(arg, &info, sizeof(info)))
5400                return -EFAULT;
5401
5402        return 0;
5403}
5404
5405static int get_bitmap_file(struct mddev * mddev, void __user * arg)
5406{
5407        mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
5408        char *ptr, *buf = NULL;
5409        int err = -ENOMEM;
5410
5411        if (md_allow_write(mddev))
5412                file = kmalloc(sizeof(*file), GFP_NOIO);
5413        else
5414                file = kmalloc(sizeof(*file), GFP_KERNEL);
5415
5416        if (!file)
5417                goto out;
5418
5419        /* bitmap disabled, zero the first byte and copy out */
5420        if (!mddev->bitmap || !mddev->bitmap->file) {
5421                file->pathname[0] = '\0';
5422                goto copy_out;
5423        }
5424
5425        buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
5426        if (!buf)
5427                goto out;
5428
5429        ptr = d_path(&mddev->bitmap->file->f_path, buf, sizeof(file->pathname));
5430        if (IS_ERR(ptr))
5431                goto out;
5432
5433        strcpy(file->pathname, ptr);
5434
5435copy_out:
5436        err = 0;
5437        if (copy_to_user(arg, file, sizeof(*file)))
5438                err = -EFAULT;
5439out:
5440        kfree(buf);
5441        kfree(file);
5442        return err;
5443}
5444
5445static int get_disk_info(struct mddev * mddev, void __user * arg)
5446{
5447        mdu_disk_info_t info;
5448        struct md_rdev *rdev;
5449
5450        if (copy_from_user(&info, arg, sizeof(info)))
5451                return -EFAULT;
5452
5453        rdev = find_rdev_nr(mddev, info.number);
5454        if (rdev) {
5455                info.major = MAJOR(rdev->bdev->bd_dev);
5456                info.minor = MINOR(rdev->bdev->bd_dev);
5457                info.raid_disk = rdev->raid_disk;
5458                info.state = 0;
5459                if (test_bit(Faulty, &rdev->flags))
5460                        info.state |= (1<<MD_DISK_FAULTY);
5461                else if (test_bit(In_sync, &rdev->flags)) {
5462                        info.state |= (1<<MD_DISK_ACTIVE);
5463                        info.state |= (1<<MD_DISK_SYNC);
5464                }
5465                if (test_bit(WriteMostly, &rdev->flags))
5466                        info.state |= (1<<MD_DISK_WRITEMOSTLY);
5467        } else {
5468                info.major = info.minor = 0;
5469                info.raid_disk = -1;
5470                info.state = (1<<MD_DISK_REMOVED);
5471        }
5472
5473        if (copy_to_user(arg, &info, sizeof(info)))
5474                return -EFAULT;
5475
5476        return 0;
5477}
5478
5479static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
5480{
5481        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
5482        struct md_rdev *rdev;
5483        dev_t dev = MKDEV(info->major,info->minor);
5484
5485        if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
5486                return -EOVERFLOW;
5487
5488        if (!mddev->raid_disks) {
5489                int err;
5490                /* expecting a device which has a superblock */
5491                rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
5492                if (IS_ERR(rdev)) {
5493                        printk(KERN_WARNING 
5494                                "md: md_import_device returned %ld\n",
5495                                PTR_ERR(rdev));
5496                        return PTR_ERR(rdev);
5497                }
5498                if (!list_empty(&mddev->disks)) {
5499                        struct md_rdev *rdev0
5500                                = list_entry(mddev->disks.next,
5501                                             struct md_rdev, same_set);
5502                        err = super_types[mddev->major_version]
5503                                .load_super(rdev, rdev0, mddev->minor_version);
5504                        if (err < 0) {
5505                                printk(KERN_WARNING 
5506                                        "md: %s has different UUID to %s\n",
5507                                        bdevname(rdev->bdev,b), 
5508                                        bdevname(rdev0->bdev,b2));
5509                                export_rdev(rdev);
5510                                return -EINVAL;
5511                        }
5512                }
5513                err = bind_rdev_to_array(rdev, mddev);
5514                if (err)
5515                        export_rdev(rdev);
5516                return err;
5517        }
5518
5519        /*
5520         * add_new_disk can be used once the array is assembled
5521         * to add "hot spares".  They must already have a superblock
5522         * written
5523         */
5524        if (mddev->pers) {
5525                int err;
5526                if (!mddev->pers->hot_add_disk) {
5527                        printk(KERN_WARNING 
5528                                "%s: personality does not support diskops!\n",
5529                               mdname(mddev));
5530                        return -EINVAL;
5531                }
5532                if (mddev->persistent)
5533                        rdev = md_import_device(dev, mddev->major_version,
5534                                                mddev->minor_version);
5535                else
5536                        rdev = md_import_device(dev, -1, -1);
5537                if (IS_ERR(rdev)) {
5538                        printk(KERN_WARNING 
5539                                "md: md_import_device returned %ld\n",
5540                                PTR_ERR(rdev));
5541                        return PTR_ERR(rdev);
5542                }
5543                /* set saved_raid_disk if appropriate */
5544                if (!mddev->persistent) {
5545                        if (info->state & (1<<MD_DISK_SYNC)  &&
5546                            info->raid_disk < mddev->raid_disks) {
5547                                rdev->raid_disk = info->raid_disk;
5548                                set_bit(In_sync, &rdev->flags);
5549                        } else
5550                                rdev->raid_disk = -1;
5551                } else
5552                        super_types[mddev->major_version].
5553                                validate_super(mddev, rdev);
5554                if ((info->state & (1<<MD_DISK_SYNC)) &&
5555                    (!test_bit(In_sync, &rdev->flags) ||
5556                     rdev->raid_disk != info->raid_disk)) {
5557                        /* This was a hot-add request, but events doesn't
5558                         * match, so reject it.
5559                         */
5560                        export_rdev(rdev);
5561                        return -EINVAL;
5562                }
5563
5564                if (test_bit(In_sync, &rdev->flags))
5565                        rdev->saved_raid_disk = rdev->raid_disk;
5566                else
5567                        rdev->saved_raid_disk = -1;
5568
5569                clear_bit(In_sync, &rdev->flags); /* just to be sure */
5570                if (info->state & (1<<MD_DISK_WRITEMOSTLY))
5571                        set_bit(WriteMostly, &rdev->flags);
5572                else
5573                        clear_bit(WriteMostly, &rdev->flags);
5574
5575                rdev->raid_disk = -1;
5576                err = bind_rdev_to_array(rdev, mddev);
5577                if (!err && !mddev->pers->hot_remove_disk) {
5578                        /* If there is hot_add_disk but no hot_remove_disk
5579                         * then added disks for geometry changes,
5580                         * and should be added immediately.
5581                         */
5582                        super_types[mddev->major_version].
5583                                validate_super(mddev, rdev);
5584                        err = mddev->pers->hot_add_disk(mddev, rdev);
5585                        if (err)
5586                                unbind_rdev_from_array(rdev);
5587                }
5588                if (err)
5589                        export_rdev(rdev);
5590                else
5591                        sysfs_notify_dirent_safe(rdev->sysfs_state);
5592
5593                md_update_sb(mddev, 1);
5594                if (mddev->degraded)
5595                        set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
5596                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5597                if (!err)
5598                        md_new_event(mddev);
5599                md_wakeup_thread(mddev->thread);
5600                return err;
5601        }
5602
5603        /* otherwise, add_new_disk is only allowed
5604         * for major_version==0 superblocks
5605         */
5606        if (mddev->major_version != 0) {
5607                printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
5608                       mdname(mddev));
5609                return -EINVAL;
5610        }
5611
5612        if (!(info->state & (1<<MD_DISK_FAULTY))) {
5613                int err;
5614                rdev = md_import_device(dev, -1, 0);
5615                if (IS_ERR(rdev)) {
5616                        printk(KERN_WARNING 
5617                                "md: error, md_import_device() returned %ld\n",
5618                                PTR_ERR(rdev));
5619                        return PTR_ERR(rdev);
5620                }
5621                rdev->desc_nr = info->number;
5622                if (info->raid_disk < mddev->raid_disks)
5623                        rdev->raid_disk = info->raid_disk;
5624                else
5625                        rdev->raid_disk = -1;
5626
5627                if (rdev->raid_disk < mddev->raid_disks)
5628                        if (info->state & (1<<MD_DISK_SYNC))
5629                                set_bit(In_sync, &rdev->flags);
5630
5631                if (info->state & (1<<MD_DISK_WRITEMOSTLY))
5632                        set_bit(WriteMostly, &rdev->flags);
5633
5634                if (!mddev->persistent) {
5635                        printk(KERN_INFO "md: nonpersistent superblock ...\n");
5636                        rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
5637                } else
5638                        rdev->sb_start = calc_dev_sboffset(rdev);
5639                rdev->sectors = rdev->sb_start;
5640
5641                err = bind_rdev_to_array(rdev, mddev);
5642                if (err) {
5643                        export_rdev(rdev);
5644                        return err;
5645                }
5646        }
5647
5648        return 0;
5649}
5650
5651static int hot_remove_disk(struct mddev * mddev, dev_t dev)
5652{
5653        char b[BDEVNAME_SIZE];
5654        struct md_rdev *rdev;
5655
5656        rdev = find_rdev(mddev, dev);
5657        if (!rdev)
5658                return -ENXIO;
5659
5660        if (rdev->raid_disk >= 0)
5661                goto busy;
5662
5663        kick_rdev_from_array(rdev);
5664        md_update_sb(mddev, 1);
5665        md_new_event(mddev);
5666
5667        return 0;
5668busy:
5669        printk(KERN_WARNING "md: cannot remove active disk %s from %s ...\n",
5670                bdevname(rdev->bdev,b), mdname(mddev));
5671        return -EBUSY;
5672}
5673
5674static int hot_add_disk(struct mddev * mddev, dev_t dev)
5675{
5676        char b[BDEVNAME_SIZE];
5677        int err;
5678        struct md_rdev *rdev;
5679
5680        if (!mddev->pers)
5681                return -ENODEV;
5682
5683        if (mddev->major_version != 0) {
5684                printk(KERN_WARNING "%s: HOT_ADD may only be used with"
5685                        " version-0 superblocks.\n",
5686                        mdname(mddev));
5687                return -EINVAL;
5688        }
5689        if (!mddev->pers->hot_add_disk) {
5690                printk(KERN_WARNING 
5691                        "%s: personality does not support diskops!\n",
5692                        mdname(mddev));
5693                return -EINVAL;
5694        }
5695
5696        rdev = md_import_device(dev, -1, 0);
5697        if (IS_ERR(rdev)) {
5698                printk(KERN_WARNING 
5699                        "md: error, md_import_device() returned %ld\n",
5700                        PTR_ERR(rdev));
5701                return -EINVAL;
5702        }
5703
5704        if (mddev->persistent)
5705                rdev->sb_start = calc_dev_sboffset(rdev);
5706        else
5707                rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
5708
5709        rdev->sectors = rdev->sb_start;
5710
5711        if (test_bit(Faulty, &rdev->flags)) {
5712                printk(KERN_WARNING 
5713                        "md: can not hot-add faulty %s disk to %s!\n",
5714                        bdevname(rdev->bdev,b), mdname(mddev));
5715                err = -EINVAL;
5716                goto abort_export;
5717        }
5718        clear_bit(In_sync, &rdev->flags);
5719        rdev->desc_nr = -1;
5720        rdev->saved_raid_disk = -1;
5721        err = bind_rdev_to_array(rdev, mddev);
5722        if (err)
5723                goto abort_export;
5724
5725        /*
5726         * The rest should better be atomic, we can have disk failures
5727         * noticed in interrupt contexts ...
5728         */
5729
5730        rdev->raid_disk = -1;
5731
5732        md_update_sb(mddev, 1);
5733
5734        /*
5735         * Kick recovery, maybe this spare has to be added to the
5736         * array immediately.
5737         */
5738        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
5739        md_wakeup_thread(mddev->thread);
5740        md_new_event(mddev);
5741        return 0;
5742
5743abort_export:
5744        export_rdev(rdev);
5745        return err;
5746}
5747
5748static int set_bitmap_file(struct mddev *mddev, int fd)
5749{
5750        int err;
5751
5752        if (mddev->pers) {
5753                if (!mddev->pers->quiesce)
5754                        return -EBUSY;
5755                if (mddev->recovery || mddev->sync_thread)
5756                        return -EBUSY;
5757                /* we should be able to change the bitmap.. */
5758        }
5759
5760
5761        if (fd >= 0) {
5762                if (mddev->bitmap)
5763                        return -EEXIST; /* cannot add when bitmap is present */
5764                mddev->bitmap_info.file = fget(fd);
5765
5766                if (mddev->bitmap_info.file == NULL) {
5767                        printk(KERN_ERR "%s: error: failed to get bitmap file\n",
5768                               mdname(mddev));
5769                        return -EBADF;
5770                }
5771
5772                err = deny_bitmap_write_access(mddev->bitmap_info.file);
5773                if (err) {
5774                        printk(KERN_ERR "%s: error: bitmap file is already in use\n",
5775                               mdname(mddev));
5776                        fput(mddev->bitmap_info.file);
5777                        mddev->bitmap_info.file = NULL;
5778                        return err;
5779                }
5780                mddev->bitmap_info.offset = 0; /* file overrides offset */
5781        } else if (mddev->bitmap == NULL)
5782                return -ENOENT; /* cannot remove what isn't there */
5783        err = 0;
5784        if (mddev->pers) {
5785                mddev->pers->quiesce(mddev, 1);
5786                if (fd >= 0) {
5787                        err = bitmap_create(mddev);
5788                        if (!err)
5789                                err = bitmap_load(mddev);
5790                }
5791                if (fd < 0 || err) {
5792                        bitmap_destroy(mddev);
5793                        fd = -1; /* make sure to put the file */
5794                }
5795                mddev->pers->quiesce(mddev, 0);
5796        }
5797        if (fd < 0) {
5798                if (mddev->bitmap_info.file) {
5799                        restore_bitmap_write_access(mddev->bitmap_info.file);
5800                        fput(mddev->bitmap_info.file);
5801                }
5802                mddev->bitmap_info.file = NULL;
5803        }
5804
5805        return err;
5806}
5807
5808/*
5809 * set_array_info is used two different ways
5810 * The original usage is when creating a new array.
5811 * In this usage, raid_disks is > 0 and it together with
5812 *  level, size, not_persistent,layout,chunksize determine the
5813 *  shape of the array.
5814 *  This will always create an array with a type-0.90.0 superblock.
5815 * The newer usage is when assembling an array.
5816 *  In this case raid_disks will be 0, and the major_version field is
5817 *  use to determine which style super-blocks are to be found on the devices.
5818 *  The minor and patch _version numbers are also kept incase the
5819 *  super_block handler wishes to interpret them.
5820 */
5821static int set_array_info(struct mddev * mddev, mdu_array_info_t *info)
5822{
5823
5824        if (info->raid_disks == 0) {
5825                /* just setting version number for superblock loading */
5826                if (info->major_version < 0 ||
5827                    info->major_version >= ARRAY_SIZE(super_types) ||
5828                    super_types[info->major_version].name == NULL) {
5829                        /* maybe try to auto-load a module? */
5830                        printk(KERN_INFO 
5831                                "md: superblock version %d not known\n",
5832                                info->major_version);
5833                        return -EINVAL;
5834                }
5835                mddev->major_version = info->major_version;
5836                mddev->minor_version = info->minor_version;
5837                mddev->patch_version = info->patch_version;
5838                mddev->persistent = !info->not_persistent;
5839                /* ensure mddev_put doesn't delete this now that there
5840                 * is some minimal configuration.
5841                 */
5842                mddev->ctime         = get_seconds();
5843                return 0;
5844        }
5845        mddev->major_version = MD_MAJOR_VERSION;
5846        mddev->minor_version = MD_MINOR_VERSION;
5847        mddev->patch_version = MD_PATCHLEVEL_VERSION;
5848        mddev->ctime         = get_seconds();
5849
5850        mddev->level         = info->level;
5851        mddev->clevel[0]     = 0;
5852        mddev->dev_sectors   = 2 * (sector_t)info->size;
5853        mddev->raid_disks    = info->raid_disks;
5854        /* don't set md_minor, it is determined by which /dev/md* was
5855         * openned
5856         */
5857        if (info->state & (1<<MD_SB_CLEAN))
5858                mddev->recovery_cp = MaxSector;
5859        else
5860                mddev->recovery_cp = 0;
5861        mddev->persistent    = ! info->not_persistent;
5862        mddev->external      = 0;
5863
5864        mddev->layout        = info->layout;
5865        mddev->chunk_sectors = info->chunk_size >> 9;
5866
5867        mddev->max_disks     = MD_SB_DISKS;
5868
5869        if (mddev->persistent)
5870                mddev->flags         = 0;
5871        set_bit(MD_CHANGE_DEVS, &mddev->flags);
5872
5873        mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
5874        mddev->bitmap_info.offset = 0;
5875
5876        mddev->reshape_position = MaxSector;
5877
5878        /*
5879         * Generate a 128 bit UUID
5880         */
5881        get_random_bytes(mddev->uuid, 16);
5882
5883        mddev->new_level = mddev->level;
5884        mddev->new_chunk_sectors = mddev->chunk_sectors;
5885        mddev->new_layout = mddev->layout;
5886        mddev->delta_disks = 0;
5887
5888        return 0;
5889}
5890
5891void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors)
5892{
5893        WARN(!mddev_is_locked(mddev), "%s: unlocked mddev!\n", __func__);
5894
5895        if (mddev->external_size)
5896                return;
5897
5898        mddev->array_sectors = array_sectors;
5899}
5900EXPORT_SYMBOL(md_set_array_sectors);
5901
5902static int update_size(struct mddev *mddev, sector_t num_sectors)
5903{
5904        struct md_rdev *rdev;
5905        int rv;
5906        int fit = (num_sectors == 0);
5907
5908        if (mddev->pers->resize == NULL)
5909                return -EINVAL;
5910        /* The "num_sectors" is the number of sectors of each device that
5911         * is used.  This can only make sense for arrays with redundancy.
5912         * linear and raid0 always use whatever space is available. We can only
5913         * consider changing this number if no resync or reconstruction is
5914         * happening, and if the new size is acceptable. It must fit before the
5915         * sb_start or, if that is <data_offset, it must fit before the size
5916         * of each device.  If num_sectors is zero, we find the largest size
5917         * that fits.
5918         */
5919        if (mddev->sync_thread)
5920                return -EBUSY;
5921        if (mddev->bitmap)
5922                /* Sorry, cannot grow a bitmap yet, just remove it,
5923                 * grow, and re-add.
5924                 */
5925                return -EBUSY;
5926        list_for_each_entry(rdev, &mddev->disks, same_set) {
5927                sector_t avail = rdev->sectors;
5928
5929                if (fit && (num_sectors == 0 || num_sectors > avail))
5930                        num_sectors = avail;
5931                if (avail < num_sectors)
5932                        return -ENOSPC;
5933        }
5934        rv = mddev->pers->resize(mddev, num_sectors);
5935        if (!rv)
5936                revalidate_disk(mddev->gendisk);
5937        return rv;
5938}
5939
5940static int update_raid_disks(struct mddev *mddev, int raid_disks)
5941{
5942        int rv;
5943        /* change the number of raid disks */
5944        if (mddev->pers->check_reshape == NULL)
5945                return -EINVAL;
5946        if (raid_disks <= 0 ||
5947            (mddev->max_disks && raid_disks >= mddev->max_disks))
5948                return -EINVAL;
5949        if (mddev->sync_thread || mddev->reshape_position != MaxSector)
5950                return -EBUSY;
5951        mddev->delta_disks = raid_disks - mddev->raid_disks;
5952
5953        rv = mddev->pers->check_reshape(mddev);
5954        if (rv < 0)
5955                mddev->delta_disks = 0;
5956        return rv;
5957}
5958
5959
5960/*
5961 * update_array_info is used to change the configuration of an
5962 * on-line array.
5963 * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
5964 * fields in the info are checked against the array.
5965 * Any differences that cannot be handled will cause an error.
5966 * Normally, only one change can be managed at a time.
5967 */
5968static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
5969{
5970        int rv = 0;
5971        int cnt = 0;
5972        int state = 0;
5973
5974        /* calculate expected state,ignoring low bits */
5975        if (mddev->bitmap && mddev->bitmap_info.offset)
5976                state |= (1 << MD_SB_BITMAP_PRESENT);
5977
5978        if (mddev->major_version != info->major_version ||
5979            mddev->minor_version != info->minor_version ||
5980/*          mddev->patch_version != info->patch_version || */
5981            mddev->ctime         != info->ctime         ||
5982            mddev->level         != info->level         ||
5983/*          mddev->layout        != info->layout        || */
5984            !mddev->persistent   != info->not_persistent||
5985            mddev->chunk_sectors != info->chunk_size >> 9 ||
5986            /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
5987            ((state^info->state) & 0xfffffe00)
5988                )
5989                return -EINVAL;
5990        /* Check there is only one change */
5991        if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
5992                cnt++;
5993        if (mddev->raid_disks != info->raid_disks)
5994                cnt++;
5995        if (mddev->layout != info->layout)
5996                cnt++;
5997        if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
5998                cnt++;
5999        if (cnt == 0)
6000                return 0;
6001        if (cnt > 1)
6002                return -EINVAL;
6003
6004        if (mddev->layout != info->layout) {
6005                /* Change layout
6006                 * we don't need to do anything at the md level, the
6007                 * personality will take care of it all.
6008                 */
6009                if (mddev->pers->check_reshape == NULL)
6010                        return -EINVAL;
6011                else {
6012                        mddev->new_layout = info->layout;
6013                        rv = mddev->pers->check_reshape(mddev);
6014                        if (rv)
6015                                mddev->new_layout = mddev->layout;
6016                        return rv;
6017                }
6018        }
6019        if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
6020                rv = update_size(mddev, (sector_t)info->size * 2);
6021
6022        if (mddev->raid_disks    != info->raid_disks)
6023                rv = update_raid_disks(mddev, info->raid_disks);
6024
6025        if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
6026                if (mddev->pers->quiesce == NULL)
6027                        return -EINVAL;
6028                if (mddev->recovery || mddev->sync_thread)
6029                        return -EBUSY;
6030                if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
6031                        /* add the bitmap */
6032                        if (mddev->bitmap)
6033                                return -EEXIST;
6034                        if (mddev->bitmap_info.default_offset == 0)
6035                                return -EINVAL;
6036                        mddev->bitmap_info.offset =
6037                                mddev->bitmap_info.default_offset;
6038                        mddev->pers->quiesce(mddev, 1);
6039                        rv = bitmap_create(mddev);
6040                        if (!rv)
6041                                rv = bitmap_load(mddev);
6042                        if (rv)
6043                                bitmap_destroy(mddev);
6044                        mddev->pers->quiesce(mddev, 0);
6045                } else {
6046                        /* remove the bitmap */
6047                        if (!mddev->bitmap)
6048                                return -ENOENT;
6049                        if (mddev->bitmap->file)
6050                                return -EINVAL;
6051                        mddev->pers->quiesce(mddev, 1);
6052                        bitmap_destroy(mddev);
6053                        mddev->pers->quiesce(mddev, 0);
6054                        mddev->bitmap_info.offset = 0;
6055                }
6056        }
6057        md_update_sb(mddev, 1);
6058        return rv;
6059}
6060
6061static int set_disk_faulty(struct mddev *mddev, dev_t dev)
6062{
6063        struct md_rdev *rdev;
6064
6065        if (mddev->pers == NULL)
6066                return -ENODEV;
6067
6068        rdev = find_rdev(mddev, dev);
6069        if (!rdev)
6070                return -ENODEV;
6071
6072        md_error(mddev, rdev);
6073        if (!test_bit(Faulty, &rdev->flags))
6074                return -EBUSY;
6075        return 0;
6076}
6077
6078/*
6079 * We have a problem here : there is no easy way to give a CHS
6080 * virtual geometry. We currently pretend that we have a 2 heads
6081 * 4 sectors (with a BIG number of cylinders...). This drives
6082 * dosfs just mad... ;-)
6083 */
6084static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
6085{
6086        struct mddev *mddev = bdev->bd_disk->private_data;
6087
6088        geo->heads = 2;
6089        geo->sectors = 4;
6090        geo->cylinders = mddev->array_sectors / 8;
6091        return 0;
6092}
6093
6094static int md_ioctl(struct block_device *bdev, fmode_t mode,
6095                        unsigned int cmd, unsigned long arg)
6096{
6097        int err = 0;
6098        void __user *argp = (void __user *)arg;
6099        struct mddev *mddev = NULL;
6100        int ro;
6101
6102        switch (cmd) {
6103        case RAID_VERSION:
6104        case GET_ARRAY_INFO:
6105        case GET_DISK_INFO:
6106                break;
6107        default:
6108                if (!capable(CAP_SYS_ADMIN))
6109                        return -EACCES;
6110        }
6111
6112        /*
6113         * Commands dealing with the RAID driver but not any
6114         * particular array:
6115         */
6116        switch (cmd)
6117        {
6118                case RAID_VERSION:
6119                        err = get_version(argp);
6120                        goto done;
6121
6122                case PRINT_RAID_DEBUG:
6123                        err = 0;
6124                        md_print_devices();
6125                        goto done;
6126
6127#ifndef MODULE
6128                case RAID_AUTORUN:
6129                        err = 0;
6130                        autostart_arrays(arg);
6131                        goto done;
6132#endif
6133                default:;
6134        }
6135
6136        /*
6137         * Commands creating/starting a new array:
6138         */
6139
6140        mddev = bdev->bd_disk->private_data;
6141
6142        if (!mddev) {
6143                BUG();
6144                goto abort;
6145        }
6146
6147        err = mddev_lock(mddev);
6148        if (err) {
6149                printk(KERN_INFO 
6150                        "md: ioctl lock interrupted, reason %d, cmd %d\n",
6151                        err, cmd);
6152                goto abort;
6153        }
6154
6155        switch (cmd)
6156        {
6157                case SET_ARRAY_INFO:
6158                        {
6159                                mdu_array_info_t info;
6160                                if (!arg)
6161                                        memset(&info, 0, sizeof(info));
6162                                else if (copy_from_user(&info, argp, sizeof(info))) {
6163                                        err = -EFAULT;
6164                                        goto abort_unlock;
6165                                }
6166                                if (mddev->pers) {
6167                                        err = update_array_info(mddev, &info);
6168                                        if (err) {
6169                                                printk(KERN_WARNING "md: couldn't update"
6170                                                       " array info. %d\n", err);
6171                                                goto abort_unlock;
6172                                        }
6173                                        goto done_unlock;
6174                                }
6175                                if (!list_empty(&mddev->disks)) {
6176                                        printk(KERN_WARNING
6177                                               "md: array %s already has disks!\n",
6178                                               mdname(mddev));
6179                                        err = -EBUSY;
6180                                        goto abort_unlock;
6181                                }
6182                                if (mddev->raid_disks) {
6183                                        printk(KERN_WARNING
6184                                               "md: array %s already initialised!\n",
6185                                               mdname(mddev));
6186                                        err = -EBUSY;
6187                                        goto abort_unlock;
6188                                }
6189                                err = set_array_info(mddev, &info);
6190                                if (err) {
6191                                        printk(KERN_WARNING "md: couldn't set"
6192                                               " array info. %d\n", err);
6193                                        goto abort_unlock;
6194                                }
6195                        }
6196                        goto done_unlock;
6197
6198                default:;
6199        }
6200
6201        /*
6202         * Commands querying/configuring an existing array:
6203         */
6204        /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
6205         * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
6206        if ((!mddev->raid_disks && !mddev->external)
6207            && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
6208            && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
6209            && cmd != GET_BITMAP_FILE) {
6210                err = -ENODEV;
6211                goto abort_unlock;
6212        }
6213
6214        /*
6215         * Commands even a read-only array can execute:
6216         */
6217        switch (cmd)
6218        {
6219                case GET_ARRAY_INFO:
6220                        err = get_array_info(mddev, argp);
6221                        goto done_unlock;
6222
6223                case GET_BITMAP_FILE:
6224                        err = get_bitmap_file(mddev, argp);
6225                        goto done_unlock;
6226
6227                case GET_DISK_INFO:
6228                        err = get_disk_info(mddev, argp);
6229                        goto done_unlock;
6230
6231                case RESTART_ARRAY_RW:
6232                        err = restart_array(mddev);
6233                        goto done_unlock;
6234
6235                case STOP_ARRAY:
6236                        err = do_md_stop(mddev, 0, 1);
6237                        goto done_unlock;
6238
6239                case STOP_ARRAY_RO:
6240                        err = md_set_readonly(mddev, 1);
6241                        goto done_unlock;
6242
6243                case BLKROSET:
6244                        if (get_user(ro, (int __user *)(arg))) {
6245                                err = -EFAULT;
6246                                goto done_unlock;
6247                        }
6248                        err = -EINVAL;
6249
6250                        /* if the bdev is going readonly the value of mddev->ro
6251                         * does not matter, no writes are coming
6252                         */
6253                        if (ro)
6254                                goto done_unlock;
6255
6256                        /* are we are already prepared for writes? */
6257                        if (mddev->ro != 1)
6258                                goto done_unlock;
6259
6260                        /* transitioning to readauto need only happen for
6261                         * arrays that call md_write_start
6262                         */
6263                        if (mddev->pers) {
6264                                err = restart_array(mddev);
6265                                if (err == 0) {
6266                                        mddev->ro = 2;
6267                                        set_disk_ro(mddev->gendisk, 0);
6268                                }
6269                        }
6270                        goto done_unlock;
6271        }
6272
6273        /*
6274         * The remaining ioctls are changing the state of the
6275         * superblock, so we do not allow them on read-only arrays.
6276         * However non-MD ioctls (e.g. get-size) will still come through
6277         * here and hit the 'default' below, so only disallow
6278         * 'md' ioctls, and switch to rw mode if started auto-readonly.
6279         */
6280        if (_IOC_TYPE(cmd) == MD_MAJOR && mddev->ro && mddev->pers) {
6281                if (mddev->ro == 2) {
6282                        mddev->ro = 0;
6283                        sysfs_notify_dirent_safe(mddev->sysfs_state);
6284                        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6285                        md_wakeup_thread(mddev->thread);
6286                } else {
6287                        err = -EROFS;
6288                        goto abort_unlock;
6289                }
6290        }
6291
6292        switch (cmd)
6293        {
6294                case ADD_NEW_DISK:
6295                {
6296                        mdu_disk_info_t info;
6297                        if (copy_from_user(&info, argp, sizeof(info)))
6298                                err = -EFAULT;
6299                        else
6300                                err = add_new_disk(mddev, &info);
6301                        goto done_unlock;
6302                }
6303
6304                case HOT_REMOVE_DISK:
6305                        err = hot_remove_disk(mddev, new_decode_dev(arg));
6306                        goto done_unlock;
6307
6308                case HOT_ADD_DISK:
6309                        err = hot_add_disk(mddev, new_decode_dev(arg));
6310                        goto done_unlock;
6311
6312                case SET_DISK_FAULTY:
6313                        err = set_disk_faulty(mddev, new_decode_dev(arg));
6314                        goto done_unlock;
6315
6316                case RUN_ARRAY:
6317                        err = do_md_run(mddev);
6318                        goto done_unlock;
6319
6320                case SET_BITMAP_FILE:
6321                        err = set_bitmap_file(mddev, (int)arg);
6322                        goto done_unlock;
6323
6324                default:
6325                        err = -EINVAL;
6326                        goto abort_unlock;
6327        }
6328
6329done_unlock:
6330abort_unlock:
6331        if (mddev->hold_active == UNTIL_IOCTL &&
6332            err != -EINVAL)
6333                mddev->hold_active = 0;
6334        mddev_unlock(mddev);
6335
6336        return err;
6337done:
6338        if (err)
6339                MD_BUG();
6340abort:
6341        return err;
6342}
6343#ifdef CONFIG_COMPAT
6344static int md_compat_ioctl(struct block_device *bdev, fmode_t mode,
6345                    unsigned int cmd, unsigned long arg)
6346{
6347        switch (cmd) {
6348        case HOT_REMOVE_DISK:
6349        case HOT_ADD_DISK:
6350        case SET_DISK_FAULTY:
6351        case SET_BITMAP_FILE:
6352                /* These take in integer arg, do not convert */
6353                break;
6354        default:
6355                arg = (unsigned long)compat_ptr(arg);
6356                break;
6357        }
6358
6359        return md_ioctl(bdev, mode, cmd, arg);
6360}
6361#endif /* CONFIG_COMPAT */
6362
6363static int md_open(struct block_device *bdev, fmode_t mode)
6364{
6365        /*
6366         * Succeed if we can lock the mddev, which confirms that
6367         * it isn't being stopped right now.
6368         */
6369        struct mddev *mddev = mddev_find(bdev->bd_dev);
6370        int err;
6371
6372        if (mddev->gendisk != bdev->bd_disk) {
6373                /* we are racing with mddev_put which is discarding this
6374                 * bd_disk.
6375                 */
6376                mddev_put(mddev);
6377                /* Wait until bdev->bd_disk is definitely gone */
6378                flush_workqueue(md_misc_wq);
6379                /* Then retry the open from the top */
6380                return -ERESTARTSYS;
6381        }
6382        BUG_ON(mddev != bdev->bd_disk->private_data);
6383
6384        if ((err = mutex_lock_interruptible(&mddev->open_mutex)))
6385                goto out;
6386
6387        err = 0;
6388        atomic_inc(&mddev->openers);
6389        mutex_unlock(&mddev->open_mutex);
6390
6391        check_disk_change(bdev);
6392 out:
6393        return err;
6394}
6395
6396static int md_release(struct gendisk *disk, fmode_t mode)
6397{
6398        struct mddev *mddev = disk->private_data;
6399
6400        BUG_ON(!mddev);
6401        atomic_dec(&mddev->openers);
6402        mddev_put(mddev);
6403
6404        return 0;
6405}
6406
6407static int md_media_changed(struct gendisk *disk)
6408{
6409        struct mddev *mddev = disk->private_data;
6410
6411        return mddev->changed;
6412}
6413
6414static int md_revalidate(struct gendisk *disk)
6415{
6416        struct mddev *mddev = disk->private_data;
6417
6418        mddev->changed = 0;
6419        return 0;
6420}
6421static const struct block_device_operations md_fops =
6422{
6423        .owner          = THIS_MODULE,
6424        .open           = md_open,
6425        .release        = md_release,
6426        .ioctl          = md_ioctl,
6427#ifdef CONFIG_COMPAT
6428        .compat_ioctl   = md_compat_ioctl,
6429#endif
6430        .getgeo         = md_getgeo,
6431        .media_changed  = md_media_changed,
6432        .revalidate_disk= md_revalidate,
6433};
6434
6435static int md_thread(void * arg)
6436{
6437        struct md_thread *thread = arg;
6438
6439        /*
6440         * md_thread is a 'system-thread', it's priority should be very
6441         * high. We avoid resource deadlocks individually in each
6442         * raid personality. (RAID5 does preallocation) We also use RR and
6443         * the very same RT priority as kswapd, thus we will never get
6444         * into a priority inversion deadlock.
6445         *
6446         * we definitely have to have equal or higher priority than
6447         * bdflush, otherwise bdflush will deadlock if there are too
6448         * many dirty RAID5 blocks.
6449         */
6450
6451        allow_signal(SIGKILL);
6452        while (!kthread_should_stop()) {
6453
6454                /* We need to wait INTERRUPTIBLE so that
6455                 * we don't add to the load-average.
6456                 * That means we need to be sure no signals are
6457                 * pending
6458                 */
6459                if (signal_pending(current))
6460                        flush_signals(current);
6461
6462                wait_event_interruptible_timeout
6463                        (thread->wqueue,
6464                         test_bit(THREAD_WAKEUP, &thread->flags)
6465                         || kthread_should_stop(),
6466                         thread->timeout);
6467
6468                clear_bit(THREAD_WAKEUP, &thread->flags);
6469                if (!kthread_should_stop())
6470                        thread->run(thread->mddev);
6471        }
6472
6473        return 0;
6474}
6475
6476void md_wakeup_thread(struct md_thread *thread)
6477{
6478        if (thread) {
6479                pr_debug("md: waking up MD thread %s.\n", thread->tsk->comm);
6480                set_bit(THREAD_WAKEUP, &thread->flags);
6481                wake_up(&thread->wqueue);
6482        }
6483}
6484
6485struct md_thread *md_register_thread(void (*run) (struct mddev *), struct mddev *mddev,
6486                                 const char *name)
6487{
6488        struct md_thread *thread;
6489
6490        thread = kzalloc(sizeof(struct md_thread), GFP_KERNEL);
6491        if (!thread)
6492                return NULL;
6493
6494        init_waitqueue_head(&thread->wqueue);
6495
6496        thread->run = run;
6497        thread->mddev = mddev;
6498        thread->timeout = MAX_SCHEDULE_TIMEOUT;
6499        thread->tsk = kthread_run(md_thread, thread,
6500                                  "%s_%s",
6501                                  mdname(thread->mddev),
6502                                  name ?: mddev->pers->name);
6503        if (IS_ERR(thread->tsk)) {
6504                kfree(thread);
6505                return NULL;
6506        }
6507        return thread;
6508}
6509
6510void md_unregister_thread(struct md_thread **threadp)
6511{
6512        struct md_thread *thread = *threadp;
6513        if (!thread)
6514                return;
6515        pr_debug("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
6516        /* Locking ensures that mddev_unlock does not wake_up a
6517         * non-existent thread
6518         */
6519        spin_lock(&pers_lock);
6520        *threadp = NULL;
6521        spin_unlock(&pers_lock);
6522
6523        kthread_stop(thread->tsk);
6524        kfree(thread);
6525}
6526
6527void md_error(struct mddev *mddev, struct md_rdev *rdev)
6528{
6529        if (!mddev) {
6530                MD_BUG();
6531                return;
6532        }
6533
6534        if (!rdev || test_bit(Faulty, &rdev->flags))
6535                return;
6536
6537        if (!mddev->pers || !mddev->pers->error_handler)
6538                return;
6539        mddev->pers->error_handler(mddev,rdev);
6540        if (mddev->degraded)
6541                set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6542        sysfs_notify_dirent_safe(rdev->sysfs_state);
6543        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6544        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6545        md_wakeup_thread(mddev->thread);
6546        if (mddev->event_work.func)
6547                queue_work(md_misc_wq, &mddev->event_work);
6548        md_new_event_inintr(mddev);
6549}
6550
6551/* seq_file implementation /proc/mdstat */
6552
6553static void status_unused(struct seq_file *seq)
6554{
6555        int i = 0;
6556        struct md_rdev *rdev;
6557
6558        seq_printf(seq, "unused devices: ");
6559
6560        list_for_each_entry(rdev, &pending_raid_disks, same_set) {
6561                char b[BDEVNAME_SIZE];
6562                i++;
6563                seq_printf(seq, "%s ",
6564                              bdevname(rdev->bdev,b));
6565        }
6566        if (!i)
6567                seq_printf(seq, "<none>");
6568
6569        seq_printf(seq, "\n");
6570}
6571
6572
6573static void status_resync(struct seq_file *seq, struct mddev * mddev)
6574{
6575        sector_t max_sectors, resync, res;
6576        unsigned long dt, db;
6577        sector_t rt;
6578        int scale;
6579        unsigned int per_milli;
6580
6581        resync = mddev->curr_resync - atomic_read(&mddev->recovery_active);
6582
6583        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
6584                max_sectors = mddev->resync_max_sectors;
6585        else
6586                max_sectors = mddev->dev_sectors;
6587
6588        /*
6589         * Should not happen.
6590         */
6591        if (!max_sectors) {
6592                MD_BUG();
6593                return;
6594        }
6595        /* Pick 'scale' such that (resync>>scale)*1000 will fit
6596         * in a sector_t, and (max_sectors>>scale) will fit in a
6597         * u32, as those are the requirements for sector_div.
6598         * Thus 'scale' must be at least 10
6599         */
6600        scale = 10;
6601        if (sizeof(sector_t) > sizeof(unsigned long)) {
6602                while ( max_sectors/2 > (1ULL<<(scale+32)))
6603                        scale++;
6604        }
6605        res = (resync>>scale)*1000;
6606        sector_div(res, (u32)((max_sectors>>scale)+1));
6607
6608        per_milli = res;
6609        {
6610                int i, x = per_milli/50, y = 20-x;
6611                seq_printf(seq, "[");
6612                for (i = 0; i < x; i++)
6613                        seq_printf(seq, "=");
6614                seq_printf(seq, ">");
6615                for (i = 0; i < y; i++)
6616                        seq_printf(seq, ".");
6617                seq_printf(seq, "] ");
6618        }
6619        seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
6620                   (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
6621                    "reshape" :
6622                    (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
6623                     "check" :
6624                     (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
6625                      "resync" : "recovery"))),
6626                   per_milli/10, per_milli % 10,
6627                   (unsigned long long) resync/2,
6628                   (unsigned long long) max_sectors/2);
6629
6630        /*
6631         * dt: time from mark until now
6632         * db: blocks written from mark until now
6633         * rt: remaining time
6634         *
6635         * rt is a sector_t, so could be 32bit or 64bit.
6636         * So we divide before multiply in case it is 32bit and close
6637         * to the limit.
6638         * We scale the divisor (db) by 32 to avoid losing precision
6639         * near the end of resync when the number of remaining sectors
6640         * is close to 'db'.
6641         * We then divide rt by 32 after multiplying by db to compensate.
6642         * The '+1' avoids division by zero if db is very small.
6643         */
6644        dt = ((jiffies - mddev->resync_mark) / HZ);
6645        if (!dt) dt++;
6646        db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
6647                - mddev->resync_mark_cnt;
6648
6649        rt = max_sectors - resync;    /* number of remaining sectors */
6650        sector_div(rt, db/32+1);
6651        rt *= dt;
6652        rt >>= 5;
6653
6654        seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
6655                   ((unsigned long)rt % 60)/6);
6656
6657        seq_printf(seq, " speed=%ldK/sec", db/2/dt);
6658}
6659
6660static void *md_seq_start(struct seq_file *seq, loff_t *pos)
6661{
6662        struct list_head *tmp;
6663        loff_t l = *pos;
6664        struct mddev *mddev;
6665
6666        if (l >= 0x10000)
6667                return NULL;
6668        if (!l--)
6669                /* header */
6670                return (void*)1;
6671
6672        spin_lock(&all_mddevs_lock);
6673        list_for_each(tmp,&all_mddevs)
6674                if (!l--) {
6675                        mddev = list_entry(tmp, struct mddev, all_mddevs);
6676                        mddev_get(mddev);
6677                        spin_unlock(&all_mddevs_lock);
6678                        return mddev;
6679                }
6680        spin_unlock(&all_mddevs_lock);
6681        if (!l--)
6682                return (void*)2;/* tail */
6683        return NULL;
6684}
6685
6686static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
6687{
6688        struct list_head *tmp;
6689        struct mddev *next_mddev, *mddev = v;
6690        
6691        ++*pos;
6692        if (v == (void*)2)
6693                return NULL;
6694
6695        spin_lock(&all_mddevs_lock);
6696        if (v == (void*)1)
6697                tmp = all_mddevs.next;
6698        else
6699                tmp = mddev->all_mddevs.next;
6700        if (tmp != &all_mddevs)
6701                next_mddev = mddev_get(list_entry(tmp,struct mddev,all_mddevs));
6702        else {
6703                next_mddev = (void*)2;
6704                *pos = 0x10000;
6705        }               
6706        spin_unlock(&all_mddevs_lock);
6707
6708        if (v != (void*)1)
6709                mddev_put(mddev);
6710        return next_mddev;
6711
6712}
6713
6714static void md_seq_stop(struct seq_file *seq, void *v)
6715{
6716        struct mddev *mddev = v;
6717
6718        if (mddev && v != (void*)1 && v != (void*)2)
6719                mddev_put(mddev);
6720}
6721
6722static int md_seq_show(struct seq_file *seq, void *v)
6723{
6724        struct mddev *mddev = v;
6725        sector_t sectors;
6726        struct md_rdev *rdev;
6727        struct bitmap *bitmap;
6728
6729        if (v == (void*)1) {
6730                struct md_personality *pers;
6731                seq_printf(seq, "Personalities : ");
6732                spin_lock(&pers_lock);
6733                list_for_each_entry(pers, &pers_list, list)
6734                        seq_printf(seq, "[%s] ", pers->name);
6735
6736                spin_unlock(&pers_lock);
6737                seq_printf(seq, "\n");
6738                seq->poll_event = atomic_read(&md_event_count);
6739                return 0;
6740        }
6741        if (v == (void*)2) {
6742                status_unused(seq);
6743                return 0;
6744        }
6745
6746        if (mddev_lock(mddev) < 0)
6747                return -EINTR;
6748
6749        if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
6750                seq_printf(seq, "%s : %sactive", mdname(mddev),
6751                                                mddev->pers ? "" : "in");
6752                if (mddev->pers) {
6753                        if (mddev->ro==1)
6754                                seq_printf(seq, " (read-only)");
6755                        if (mddev->ro==2)
6756                                seq_printf(seq, " (auto-read-only)");
6757                        seq_printf(seq, " %s", mddev->pers->name);
6758                }
6759
6760                sectors = 0;
6761                list_for_each_entry(rdev, &mddev->disks, same_set) {
6762                        char b[BDEVNAME_SIZE];
6763                        seq_printf(seq, " %s[%d]",
6764                                bdevname(rdev->bdev,b), rdev->desc_nr);
6765                        if (test_bit(WriteMostly, &rdev->flags))
6766                                seq_printf(seq, "(W)");
6767                        if (test_bit(Faulty, &rdev->flags)) {
6768                                seq_printf(seq, "(F)");
6769                                continue;
6770                        }
6771                        if (rdev->raid_disk < 0)
6772                                seq_printf(seq, "(S)"); /* spare */
6773                        if (test_bit(Replacement, &rdev->flags))
6774                                seq_printf(seq, "(R)");
6775                        sectors += rdev->sectors;
6776                }
6777
6778                if (!list_empty(&mddev->disks)) {
6779                        if (mddev->pers)
6780                                seq_printf(seq, "\n      %llu blocks",
6781                                           (unsigned long long)
6782                                           mddev->array_sectors / 2);
6783                        else
6784                                seq_printf(seq, "\n      %llu blocks",
6785                                           (unsigned long long)sectors / 2);
6786                }
6787                if (mddev->persistent) {
6788                        if (mddev->major_version != 0 ||
6789                            mddev->minor_version != 90) {
6790                                seq_printf(seq," super %d.%d",
6791                                           mddev->major_version,
6792                                           mddev->minor_version);
6793                        }
6794                } else if (mddev->external)
6795                        seq_printf(seq, " super external:%s",
6796                                   mddev->metadata_type);
6797                else
6798                        seq_printf(seq, " super non-persistent");
6799
6800                if (mddev->pers) {
6801                        mddev->pers->status(seq, mddev);
6802                        seq_printf(seq, "\n      ");
6803                        if (mddev->pers->sync_request) {
6804                                if (mddev->curr_resync > 2) {
6805                                        status_resync(seq, mddev);
6806                                        seq_printf(seq, "\n      ");
6807                                } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
6808                                        seq_printf(seq, "\tresync=DELAYED\n      ");
6809                                else if (mddev->recovery_cp < MaxSector)
6810                                        seq_printf(seq, "\tresync=PENDING\n      ");
6811                        }
6812                } else
6813                        seq_printf(seq, "\n       ");
6814
6815                if ((bitmap = mddev->bitmap)) {
6816                        unsigned long chunk_kb;
6817                        unsigned long flags;
6818                        spin_lock_irqsave(&bitmap->lock, flags);
6819                        chunk_kb = mddev->bitmap_info.chunksize >> 10;
6820                        seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
6821                                "%lu%s chunk",
6822                                bitmap->pages - bitmap->missing_pages,
6823                                bitmap->pages,
6824                                (bitmap->pages - bitmap->missing_pages)
6825                                        << (PAGE_SHIFT - 10),
6826                                chunk_kb ? chunk_kb : mddev->bitmap_info.chunksize,
6827                                chunk_kb ? "KB" : "B");
6828                        if (bitmap->file) {
6829                                seq_printf(seq, ", file: ");
6830                                seq_path(seq, &bitmap->file->f_path, " \t\n");
6831                        }
6832
6833                        seq_printf(seq, "\n");
6834                        spin_unlock_irqrestore(&bitmap->lock, flags);
6835                }
6836
6837                seq_printf(seq, "\n");
6838        }
6839        mddev_unlock(mddev);
6840        
6841        return 0;
6842}
6843
6844static const struct seq_operations md_seq_ops = {
6845        .start  = md_seq_start,
6846        .next   = md_seq_next,
6847        .stop   = md_seq_stop,
6848        .show   = md_seq_show,
6849};
6850
6851static int md_seq_open(struct inode *inode, struct file *file)
6852{
6853        struct seq_file *seq;
6854        int error;
6855
6856        error = seq_open(file, &md_seq_ops);
6857        if (error)
6858                return error;
6859
6860        seq = file->private_data;
6861        seq->poll_event = atomic_read(&md_event_count);
6862        return error;
6863}
6864
6865static unsigned int mdstat_poll(struct file *filp, poll_table *wait)
6866{
6867        struct seq_file *seq = filp->private_data;
6868        int mask;
6869
6870        poll_wait(filp, &md_event_waiters, wait);
6871
6872        /* always allow read */
6873        mask = POLLIN | POLLRDNORM;
6874
6875        if (seq->poll_event != atomic_read(&md_event_count))
6876                mask |= POLLERR | POLLPRI;
6877        return mask;
6878}
6879
6880static const struct file_operations md_seq_fops = {
6881        .owner          = THIS_MODULE,
6882        .open           = md_seq_open,
6883        .read           = seq_read,
6884        .llseek         = seq_lseek,
6885        .release        = seq_release_private,
6886        .poll           = mdstat_poll,
6887};
6888
6889int register_md_personality(struct md_personality *p)
6890{
6891        spin_lock(&pers_lock);
6892        list_add_tail(&p->list, &pers_list);
6893        printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
6894        spin_unlock(&pers_lock);
6895        return 0;
6896}
6897
6898int unregister_md_personality(struct md_personality *p)
6899{
6900        printk(KERN_INFO "md: %s personality unregistered\n", p->name);
6901        spin_lock(&pers_lock);
6902        list_del_init(&p->list);
6903        spin_unlock(&pers_lock);
6904        return 0;
6905}
6906
6907static int is_mddev_idle(struct mddev *mddev, int init)
6908{
6909        struct md_rdev * rdev;
6910        int idle;
6911        int curr_events;
6912
6913        idle = 1;
6914        rcu_read_lock();
6915        rdev_for_each_rcu(rdev, mddev) {
6916                struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
6917                curr_events = (int)part_stat_read(&disk->part0, sectors[0]) +
6918                              (int)part_stat_read(&disk->part0, sectors[1]) -
6919                              atomic_read(&disk->sync_io);
6920                /* sync IO will cause sync_io to increase before the disk_stats
6921                 * as sync_io is counted when a request starts, and
6922                 * disk_stats is counted when it completes.
6923                 * So resync activity will cause curr_events to be smaller than
6924                 * when there was no such activity.
6925                 * non-sync IO will cause disk_stat to increase without
6926                 * increasing sync_io so curr_events will (eventually)
6927                 * be larger than it was before.  Once it becomes
6928                 * substantially larger, the test below will cause
6929                 * the array to appear non-idle, and resync will slow
6930                 * down.
6931                 * If there is a lot of outstanding resync activity when
6932                 * we set last_event to curr_events, then all that activity
6933                 * completing might cause the array to appear non-idle
6934                 * and resync will be slowed down even though there might
6935                 * not have been non-resync activity.  This will only
6936                 * happen once though.  'last_events' will soon reflect
6937                 * the state where there is little or no outstanding
6938                 * resync requests, and further resync activity will
6939                 * always make curr_events less than last_events.
6940                 *
6941                 */
6942                if (init || curr_events - rdev->last_events > 64) {
6943                        rdev->last_events = curr_events;
6944                        idle = 0;
6945                }
6946        }
6947        rcu_read_unlock();
6948        return idle;
6949}
6950
6951void md_done_sync(struct mddev *mddev, int blocks, int ok)
6952{
6953        /* another "blocks" (512byte) blocks have been synced */
6954        atomic_sub(blocks, &mddev->recovery_active);
6955        wake_up(&mddev->recovery_wait);
6956        if (!ok) {
6957                set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6958                md_wakeup_thread(mddev->thread);
6959                // stop recovery, signal do_sync ....
6960        }
6961}
6962
6963
6964/* md_write_start(mddev, bi)
6965 * If we need to update some array metadata (e.g. 'active' flag
6966 * in superblock) before writing, schedule a superblock update
6967 * and wait for it to complete.
6968 */
6969void md_write_start(struct mddev *mddev, struct bio *bi)
6970{
6971        int did_change = 0;
6972        if (bio_data_dir(bi) != WRITE)
6973                return;
6974
6975        BUG_ON(mddev->ro == 1);
6976        if (mddev->ro == 2) {
6977                /* need to switch to read/write */
6978                mddev->ro = 0;
6979                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6980                md_wakeup_thread(mddev->thread);
6981                md_wakeup_thread(mddev->sync_thread);
6982                did_change = 1;
6983        }
6984        atomic_inc(&mddev->writes_pending);
6985        if (mddev->safemode == 1)
6986                mddev->safemode = 0;
6987        if (mddev->in_sync) {
6988                spin_lock_irq(&mddev->write_lock);
6989                if (mddev->in_sync) {
6990                        mddev->in_sync = 0;
6991                        set_bit(MD_CHANGE_CLEAN, &mddev->flags);
6992                        set_bit(MD_CHANGE_PENDING, &mddev->flags);
6993                        md_wakeup_thread(mddev->thread);
6994                        did_change = 1;
6995                }
6996                spin_unlock_irq(&mddev->write_lock);
6997        }
6998        if (did_change)
6999                sysfs_notify_dirent_safe(mddev->sysfs_state);
7000        wait_event(mddev->sb_wait,
7001                   !test_bit(MD_CHANGE_PENDING, &mddev->flags));
7002}
7003
7004void md_write_end(struct mddev *mddev)
7005{
7006        if (atomic_dec_and_test(&mddev->writes_pending)) {
7007                if (mddev->safemode == 2)
7008                        md_wakeup_thread(mddev->thread);
7009                else if (mddev->safemode_delay)
7010                        mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
7011        }
7012}
7013
7014/* md_allow_write(mddev)
7015 * Calling this ensures that the array is marked 'active' so that writes
7016 * may proceed without blocking.  It is important to call this before
7017 * attempting a GFP_KERNEL allocation while holding the mddev lock.
7018 * Must be called with mddev_lock held.
7019 *
7020 * In the ->external case MD_CHANGE_CLEAN can not be cleared until mddev->lock
7021 * is dropped, so return -EAGAIN after notifying userspace.
7022 */
7023int md_allow_write(struct mddev *mddev)
7024{
7025        if (!mddev->pers)
7026                return 0;
7027        if (mddev->ro)
7028                return 0;
7029        if (!mddev->pers->sync_request)
7030                return 0;
7031
7032        spin_lock_irq(&mddev->write_lock);
7033        if (mddev->in_sync) {
7034                mddev->in_sync = 0;
7035                set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7036                set_bit(MD_CHANGE_PENDING, &mddev->flags);
7037                if (mddev->safemode_delay &&
7038                    mddev->safemode == 0)
7039                        mddev->safemode = 1;
7040                spin_unlock_irq(&mddev->write_lock);
7041                md_update_sb(mddev, 0);
7042                sysfs_notify_dirent_safe(mddev->sysfs_state);
7043        } else
7044                spin_unlock_irq(&mddev->write_lock);
7045
7046        if (test_bit(MD_CHANGE_PENDING, &mddev->flags))
7047                return -EAGAIN;
7048        else
7049                return 0;
7050}
7051EXPORT_SYMBOL_GPL(md_allow_write);
7052
7053#define SYNC_MARKS      10
7054#define SYNC_MARK_STEP  (3*HZ)
7055void md_do_sync(struct mddev *mddev)
7056{
7057        struct mddev *mddev2;
7058        unsigned int currspeed = 0,
7059                 window;
7060        sector_t max_sectors,j, io_sectors;
7061        unsigned long mark[SYNC_MARKS];
7062        sector_t mark_cnt[SYNC_MARKS];
7063        int last_mark,m;
7064        struct list_head *tmp;
7065        sector_t last_check;
7066        int skipped = 0;
7067        struct md_rdev *rdev;
7068        char *desc;
7069
7070        /* just incase thread restarts... */
7071        if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
7072                return;
7073        if (mddev->ro) /* never try to sync a read-only array */
7074                return;
7075
7076        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7077                if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
7078                        desc = "data-check";
7079                else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7080                        desc = "requested-resync";
7081                else
7082                        desc = "resync";
7083        } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
7084                desc = "reshape";
7085        else
7086                desc = "recovery";
7087
7088        /* we overload curr_resync somewhat here.
7089         * 0 == not engaged in resync at all
7090         * 2 == checking that there is no conflict with another sync
7091         * 1 == like 2, but have yielded to allow conflicting resync to
7092         *              commense
7093         * other == active in resync - this many blocks
7094         *
7095         * Before starting a resync we must have set curr_resync to
7096         * 2, and then checked that every "conflicting" array has curr_resync
7097         * less than ours.  When we find one that is the same or higher
7098         * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
7099         * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
7100         * This will mean we have to start checking from the beginning again.
7101         *
7102         */
7103
7104        do {
7105                mddev->curr_resync = 2;
7106
7107        try_again:
7108                if (kthread_should_stop())
7109                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7110
7111                if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7112                        goto skip;
7113                for_each_mddev(mddev2, tmp) {
7114                        if (mddev2 == mddev)
7115                                continue;
7116                        if (!mddev->parallel_resync
7117                        &&  mddev2->curr_resync
7118                        &&  match_mddev_units(mddev, mddev2)) {
7119                                DEFINE_WAIT(wq);
7120                                if (mddev < mddev2 && mddev->curr_resync == 2) {
7121                                        /* arbitrarily yield */
7122                                        mddev->curr_resync = 1;
7123                                        wake_up(&resync_wait);
7124                                }
7125                                if (mddev > mddev2 && mddev->curr_resync == 1)
7126                                        /* no need to wait here, we can wait the next
7127                                         * time 'round when curr_resync == 2
7128                                         */
7129                                        continue;
7130                                /* We need to wait 'interruptible' so as not to
7131                                 * contribute to the load average, and not to
7132                                 * be caught by 'softlockup'
7133                                 */
7134                                prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
7135                                if (!kthread_should_stop() &&
7136                                    mddev2->curr_resync >= mddev->curr_resync) {
7137                                        printk(KERN_INFO "md: delaying %s of %s"
7138                                               " until %s has finished (they"
7139                                               " share one or more physical units)\n",
7140                                               desc, mdname(mddev), mdname(mddev2));
7141                                        mddev_put(mddev2);
7142                                        if (signal_pending(current))
7143                                                flush_signals(current);
7144                                        schedule();
7145                                        finish_wait(&resync_wait, &wq);
7146                                        goto try_again;
7147                                }
7148                                finish_wait(&resync_wait, &wq);
7149                        }
7150                }
7151        } while (mddev->curr_resync < 2);
7152
7153        j = 0;
7154        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7155                /* resync follows the size requested by the personality,
7156                 * which defaults to physical size, but can be virtual size
7157                 */
7158                max_sectors = mddev->resync_max_sectors;
7159                mddev->resync_mismatches = 0;
7160                /* we don't use the checkpoint if there's a bitmap */
7161                if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7162                        j = mddev->resync_min;
7163                else if (!mddev->bitmap)
7164                        j = mddev->recovery_cp;
7165
7166        } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
7167                max_sectors = mddev->dev_sectors;
7168        else {
7169                /* recovery follows the physical size of devices */
7170                max_sectors = mddev->dev_sectors;
7171                j = MaxSector;
7172                rcu_read_lock();
7173                list_for_each_entry_rcu(rdev, &mddev->disks, same_set)
7174                        if (rdev->raid_disk >= 0 &&
7175                            !test_bit(Faulty, &rdev->flags) &&
7176                            !test_bit(In_sync, &rdev->flags) &&
7177                            rdev->recovery_offset < j)
7178                                j = rdev->recovery_offset;
7179                rcu_read_unlock();
7180        }
7181
7182        printk(KERN_INFO "md: %s of RAID array %s\n", desc, mdname(mddev));
7183        printk(KERN_INFO "md: minimum _guaranteed_  speed:"
7184                " %d KB/sec/disk.\n", speed_min(mddev));
7185        printk(KERN_INFO "md: using maximum available idle IO bandwidth "
7186               "(but not more than %d KB/sec) for %s.\n",
7187               speed_max(mddev), desc);
7188
7189        is_mddev_idle(mddev, 1); /* this initializes IO event counters */
7190
7191        io_sectors = 0;
7192        for (m = 0; m < SYNC_MARKS; m++) {
7193                mark[m] = jiffies;
7194                mark_cnt[m] = io_sectors;
7195        }
7196        last_mark = 0;
7197        mddev->resync_mark = mark[last_mark];
7198        mddev->resync_mark_cnt = mark_cnt[last_mark];
7199
7200        /*
7201         * Tune reconstruction:
7202         */
7203        window = 32*(PAGE_SIZE/512);
7204        printk(KERN_INFO "md: using %dk window, over a total of %lluk.\n",
7205                window/2, (unsigned long long)max_sectors/2);
7206
7207        atomic_set(&mddev->recovery_active, 0);
7208        last_check = 0;
7209
7210        if (j>2) {
7211                printk(KERN_INFO 
7212                       "md: resuming %s of %s from checkpoint.\n",
7213                       desc, mdname(mddev));
7214                mddev->curr_resync = j;
7215        }
7216        mddev->curr_resync_completed = j;
7217
7218        while (j < max_sectors) {
7219                sector_t sectors;
7220
7221                skipped = 0;
7222
7223                if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
7224                    ((mddev->curr_resync > mddev->curr_resync_completed &&
7225                      (mddev->curr_resync - mddev->curr_resync_completed)
7226                      > (max_sectors >> 4)) ||
7227                     (j - mddev->curr_resync_completed)*2
7228                     >= mddev->resync_max - mddev->curr_resync_completed
7229                            )) {
7230                        /* time to update curr_resync_completed */
7231                        wait_event(mddev->recovery_wait,
7232                                   atomic_read(&mddev->recovery_active) == 0);
7233                        mddev->curr_resync_completed = j;
7234                        set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7235                        sysfs_notify(&mddev->kobj, NULL, "sync_completed");
7236                }
7237
7238                while (j >= mddev->resync_max && !kthread_should_stop()) {
7239                        /* As this condition is controlled by user-space,
7240                         * we can block indefinitely, so use '_interruptible'
7241                         * to avoid triggering warnings.
7242                         */
7243                        flush_signals(current); /* just in case */
7244                        wait_event_interruptible(mddev->recovery_wait,
7245                                                 mddev->resync_max > j
7246                                                 || kthread_should_stop());
7247                }
7248
7249                if (kthread_should_stop())
7250                        goto interrupted;
7251
7252                sectors = mddev->pers->sync_request(mddev, j, &skipped,
7253                                                  currspeed < speed_min(mddev));
7254                if (sectors == 0) {
7255                        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7256                        goto out;
7257                }
7258
7259                if (!skipped) { /* actual IO requested */
7260                        io_sectors += sectors;
7261                        atomic_add(sectors, &mddev->recovery_active);
7262                }
7263
7264                if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7265                        break;
7266
7267                j += sectors;
7268                if (j>1) mddev->curr_resync = j;
7269                mddev->curr_mark_cnt = io_sectors;
7270                if (last_check == 0)
7271                        /* this is the earliest that rebuild will be
7272                         * visible in /proc/mdstat
7273                         */
7274                        md_new_event(mddev);
7275
7276                if (last_check + window > io_sectors || j == max_sectors)
7277                        continue;
7278
7279                last_check = io_sectors;
7280        repeat:
7281                if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
7282                        /* step marks */
7283                        int next = (last_mark+1) % SYNC_MARKS;
7284
7285                        mddev->resync_mark = mark[next];
7286                        mddev->resync_mark_cnt = mark_cnt[next];
7287                        mark[next] = jiffies;
7288                        mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
7289                        last_mark = next;
7290                }
7291
7292
7293                if (kthread_should_stop())
7294                        goto interrupted;
7295
7296
7297                /*
7298                 * this loop exits only if either when we are slower than
7299                 * the 'hard' speed limit, or the system was IO-idle for
7300                 * a jiffy.
7301                 * the system might be non-idle CPU-wise, but we only care
7302                 * about not overloading the IO subsystem. (things like an
7303                 * e2fsck being done on the RAID array should execute fast)
7304                 */
7305                cond_resched();
7306
7307                currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
7308                        /((jiffies-mddev->resync_mark)/HZ +1) +1;
7309
7310                if (currspeed > speed_min(mddev)) {
7311                        if ((currspeed > speed_max(mddev)) ||
7312                                        !is_mddev_idle(mddev, 0)) {
7313                                msleep(500);
7314                                goto repeat;
7315                        }
7316                }
7317        }
7318        printk(KERN_INFO "md: %s: %s done.\n",mdname(mddev), desc);
7319        /*
7320         * this also signals 'finished resyncing' to md_stop
7321         */
7322 out:
7323        wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
7324
7325        /* tell personality that we are finished */
7326        mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
7327
7328        if (!test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
7329            mddev->curr_resync > 2) {
7330                if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
7331                        if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
7332                                if (mddev->curr_resync >= mddev->recovery_cp) {
7333                                        printk(KERN_INFO
7334                                               "md: checkpointing %s of %s.\n",
7335                                               desc, mdname(mddev));
7336                                        mddev->recovery_cp =
7337                                                mddev->curr_resync_completed;
7338                                }
7339                        } else
7340                                mddev->recovery_cp = MaxSector;
7341                } else {
7342                        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
7343                                mddev->curr_resync = MaxSector;
7344                        rcu_read_lock();
7345                        list_for_each_entry_rcu(rdev, &mddev->disks, same_set)
7346                                if (rdev->raid_disk >= 0 &&
7347                                    mddev->delta_disks >= 0 &&
7348                                    !test_bit(Faulty, &rdev->flags) &&
7349                                    !test_bit(In_sync, &rdev->flags) &&
7350                                    rdev->recovery_offset < mddev->curr_resync)
7351                                        rdev->recovery_offset = mddev->curr_resync;
7352                        rcu_read_unlock();
7353                }
7354        }
7355 skip:
7356        set_bit(MD_CHANGE_DEVS, &mddev->flags);
7357
7358        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
7359                /* We completed so min/max setting can be forgotten if used. */
7360                if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7361                        mddev->resync_min = 0;
7362                mddev->resync_max = MaxSector;
7363        } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
7364                mddev->resync_min = mddev->curr_resync_completed;
7365        mddev->curr_resync = 0;
7366        wake_up(&resync_wait);
7367        set_bit(MD_RECOVERY_DONE, &mddev->recovery);
7368        md_wakeup_thread(mddev->thread);
7369        return;
7370
7371 interrupted:
7372        /*
7373         * got a signal, exit.
7374         */
7375        printk(KERN_INFO
7376               "md: md_do_sync() got signal ... exiting\n");
7377        set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7378        goto out;
7379
7380}
7381EXPORT_SYMBOL_GPL(md_do_sync);
7382
7383static int remove_and_add_spares(struct mddev *mddev)
7384{
7385        struct md_rdev *rdev;
7386        int spares = 0;
7387        int removed = 0;
7388
7389        mddev->curr_resync_completed = 0;
7390
7391        list_for_each_entry(rdev, &mddev->disks, same_set)
7392                if (rdev->raid_disk >= 0 &&
7393                    !test_bit(Blocked, &rdev->flags) &&
7394                    (test_bit(Faulty, &rdev->flags) ||
7395                     ! test_bit(In_sync, &rdev->flags)) &&
7396                    atomic_read(&rdev->nr_pending)==0) {
7397                        if (mddev->pers->hot_remove_disk(
7398                                    mddev, rdev) == 0) {
7399                                sysfs_unlink_rdev(mddev, rdev);
7400                                rdev->raid_disk = -1;
7401                                removed++;
7402                        }
7403                }
7404        if (removed)
7405                sysfs_notify(&mddev->kobj, NULL,
7406                             "degraded");
7407
7408
7409        list_for_each_entry(rdev, &mddev->disks, same_set) {
7410                if (rdev->raid_disk >= 0 &&
7411                    !test_bit(In_sync, &rdev->flags) &&
7412                    !test_bit(Faulty, &rdev->flags))
7413                        spares++;
7414                if (rdev->raid_disk < 0
7415                    && !test_bit(Faulty, &rdev->flags)) {
7416                        rdev->recovery_offset = 0;
7417                        if (mddev->pers->
7418                            hot_add_disk(mddev, rdev) == 0) {
7419                                if (sysfs_link_rdev(mddev, rdev))
7420                                        /* failure here is OK */;
7421                                spares++;
7422                                md_new_event(mddev);
7423                                set_bit(MD_CHANGE_DEVS, &mddev->flags);
7424                        }
7425                }
7426        }
7427        return spares;
7428}
7429
7430static void reap_sync_thread(struct mddev *mddev)
7431{
7432        struct md_rdev *rdev;
7433
7434        /* resync has finished, collect result */
7435        md_unregister_thread(&mddev->sync_thread);
7436        if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
7437            !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
7438                /* success...*/
7439                /* activate any spares */
7440                if (mddev->pers->spare_active(mddev))
7441                        sysfs_notify(&mddev->kobj, NULL,
7442                                     "degraded");
7443        }
7444        if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
7445            mddev->pers->finish_reshape)
7446                mddev->pers->finish_reshape(mddev);
7447
7448        /* If array is no-longer degraded, then any saved_raid_disk
7449         * information must be scrapped.  Also if any device is now
7450         * In_sync we must scrape the saved_raid_disk for that device
7451         * do the superblock for an incrementally recovered device
7452         * written out.
7453         */
7454        list_for_each_entry(rdev, &mddev->disks, same_set)
7455                if (!mddev->degraded ||
7456                    test_bit(In_sync, &rdev->flags))
7457                        rdev->saved_raid_disk = -1;
7458
7459        md_update_sb(mddev, 1);
7460        clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7461        clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7462        clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7463        clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7464        clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7465        /* flag recovery needed just to double check */
7466        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7467        sysfs_notify_dirent_safe(mddev->sysfs_action);
7468        md_new_event(mddev);
7469        if (mddev->event_work.func)
7470                queue_work(md_misc_wq, &mddev->event_work);
7471}
7472
7473/*
7474 * This routine is regularly called by all per-raid-array threads to
7475 * deal with generic issues like resync and super-block update.
7476 * Raid personalities that don't have a thread (linear/raid0) do not
7477 * need this as they never do any recovery or update the superblock.
7478 *
7479 * It does not do any resync itself, but rather "forks" off other threads
7480 * to do that as needed.
7481 * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
7482 * "->recovery" and create a thread at ->sync_thread.
7483 * When the thread finishes it sets MD_RECOVERY_DONE
7484 * and wakeups up this thread which will reap the thread and finish up.
7485 * This thread also removes any faulty devices (with nr_pending == 0).
7486 *
7487 * The overall approach is:
7488 *  1/ if the superblock needs updating, update it.
7489 *  2/ If a recovery thread is running, don't do anything else.
7490 *  3/ If recovery has finished, clean up, possibly marking spares active.
7491 *  4/ If there are any faulty devices, remove them.
7492 *  5/ If array is degraded, try to add spares devices
7493 *  6/ If array has spares or is not in-sync, start a resync thread.
7494 */
7495void md_check_recovery(struct mddev *mddev)
7496{
7497        if (mddev->suspended)
7498                return;
7499
7500        if (mddev->bitmap)
7501                bitmap_daemon_work(mddev);
7502
7503        if (signal_pending(current)) {
7504                if (mddev->pers->sync_request && !mddev->external) {
7505                        printk(KERN_INFO "md: %s in immediate safe mode\n",
7506                               mdname(mddev));
7507                        mddev->safemode = 2;
7508                }
7509                flush_signals(current);
7510        }
7511
7512        if (mddev->ro && !test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
7513                return;
7514        if ( ! (
7515                (mddev->flags & ~ (1<<MD_CHANGE_PENDING)) ||
7516                test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
7517                test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
7518                (mddev->external == 0 && mddev->safemode == 1) ||
7519                (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
7520                 && !mddev->in_sync && mddev->recovery_cp == MaxSector)
7521                ))
7522                return;
7523
7524        if (mddev_trylock(mddev)) {
7525                int spares = 0;
7526
7527                if (mddev->ro) {
7528                        /* Only thing we do on a ro array is remove
7529                         * failed devices.
7530                         */
7531                        struct md_rdev *rdev;
7532                        list_for_each_entry(rdev, &mddev->disks, same_set)
7533                                if (rdev->raid_disk >= 0 &&
7534                                    !test_bit(Blocked, &rdev->flags) &&
7535                                    test_bit(Faulty, &rdev->flags) &&
7536                                    atomic_read(&rdev->nr_pending)==0) {
7537                                        if (mddev->pers->hot_remove_disk(
7538                                                    mddev, rdev) == 0) {
7539                                                sysfs_unlink_rdev(mddev, rdev);
7540                                                rdev->raid_disk = -1;
7541                                        }
7542                                }
7543                        clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7544                        goto unlock;
7545                }
7546
7547                if (!mddev->external) {
7548                        int did_change = 0;
7549                        spin_lock_irq(&mddev->write_lock);
7550                        if (mddev->safemode &&
7551                            !atomic_read(&mddev->writes_pending) &&
7552                            !mddev->in_sync &&
7553                            mddev->recovery_cp == MaxSector) {
7554                                mddev->in_sync = 1;
7555                                did_change = 1;
7556                                set_bit(MD_CHANGE_CLEAN, &mddev->flags);
7557                        }
7558                        if (mddev->safemode == 1)
7559                                mddev->safemode = 0;
7560                        spin_unlock_irq(&mddev->write_lock);
7561                        if (did_change)
7562                                sysfs_notify_dirent_safe(mddev->sysfs_state);
7563                }
7564
7565                if (mddev->flags)
7566                        md_update_sb(mddev, 0);
7567
7568                if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
7569                    !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
7570                        /* resync/recovery still happening */
7571                        clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7572                        goto unlock;
7573                }
7574                if (mddev->sync_thread) {
7575                        reap_sync_thread(mddev);
7576                        goto unlock;
7577                }
7578                /* Set RUNNING before clearing NEEDED to avoid
7579                 * any transients in the value of "sync_action".
7580                 */
7581                set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7582                clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7583                /* Clear some bits that don't mean anything, but
7584                 * might be left set
7585                 */
7586                clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
7587                clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
7588
7589                if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
7590                        goto unlock;
7591                /* no recovery is running.
7592                 * remove any failed drives, then
7593                 * add spares if possible.
7594                 * Spare are also removed and re-added, to allow
7595                 * the personality to fail the re-add.
7596                 */
7597
7598                if (mddev->reshape_position != MaxSector) {
7599                        if (mddev->pers->check_reshape == NULL ||
7600                            mddev->pers->check_reshape(mddev) != 0)
7601                                /* Cannot proceed */
7602                                goto unlock;
7603                        set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7604                        clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7605                } else if ((spares = remove_and_add_spares(mddev))) {
7606                        clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7607                        clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7608                        clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7609                        set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7610                } else if (mddev->recovery_cp < MaxSector) {
7611                        set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7612                        clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7613                } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
7614                        /* nothing to be done ... */
7615                        goto unlock;
7616
7617                if (mddev->pers->sync_request) {
7618                        if (spares && mddev->bitmap && ! mddev->bitmap->file) {
7619                                /* We are adding a device or devices to an array
7620                                 * which has the bitmap stored on all devices.
7621                                 * So make sure all bitmap pages get written
7622                                 */
7623                                bitmap_write_all(mddev->bitmap);
7624                        }
7625                        mddev->sync_thread = md_register_thread(md_do_sync,
7626                                                                mddev,
7627                                                                "resync");
7628                        if (!mddev->sync_thread) {
7629                                printk(KERN_ERR "%s: could not start resync"
7630                                        " thread...\n", 
7631                                        mdname(mddev));
7632                                /* leave the spares where they are, it shouldn't hurt */
7633                                clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7634                                clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7635                                clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7636                                clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
7637                                clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7638                        } else
7639                                md_wakeup_thread(mddev->sync_thread);
7640                        sysfs_notify_dirent_safe(mddev->sysfs_action);
7641                        md_new_event(mddev);
7642                }
7643        unlock:
7644                if (!mddev->sync_thread) {
7645                        clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7646                        if (test_and_clear_bit(MD_RECOVERY_RECOVER,
7647                                               &mddev->recovery))
7648                                if (mddev->sysfs_action)
7649                                        sysfs_notify_dirent_safe(mddev->sysfs_action);
7650                }
7651                mddev_unlock(mddev);
7652        }
7653}
7654
7655void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev)
7656{
7657        sysfs_notify_dirent_safe(rdev->sysfs_state);
7658        wait_event_timeout(rdev->blocked_wait,
7659                           !test_bit(Blocked, &rdev->flags) &&
7660                           !test_bit(BlockedBadBlocks, &rdev->flags),
7661                           msecs_to_jiffies(5000));
7662        rdev_dec_pending(rdev, mddev);
7663}
7664EXPORT_SYMBOL(md_wait_for_blocked_rdev);
7665
7666
7667/* Bad block management.
7668 * We can record which blocks on each device are 'bad' and so just
7669 * fail those blocks, or that stripe, rather than the whole device.
7670 * Entries in the bad-block table are 64bits wide.  This comprises:
7671 * Length of bad-range, in sectors: 0-511 for lengths 1-512
7672 * Start of bad-range, sector offset, 54 bits (allows 8 exbibytes)
7673 *  A 'shift' can be set so that larger blocks are tracked and
7674 *  consequently larger devices can be covered.
7675 * 'Acknowledged' flag - 1 bit. - the most significant bit.
7676 *
7677 * Locking of the bad-block table uses a seqlock so md_is_badblock
7678 * might need to retry if it is very unlucky.
7679 * We will sometimes want to check for bad blocks in a bi_end_io function,
7680 * so we use the write_seqlock_irq variant.
7681 *
7682 * When looking for a bad block we specify a range and want to
7683 * know if any block in the range is bad.  So we binary-search
7684 * to the last range that starts at-or-before the given endpoint,
7685 * (or "before the sector after the target range")
7686 * then see if it ends after the given start.
7687 * We return
7688 *  0 if there are no known bad blocks in the range
7689 *  1 if there are known bad block which are all acknowledged
7690 * -1 if there are bad blocks which have not yet been acknowledged in metadata.
7691 * plus the start/length of the first bad section we overlap.
7692 */
7693int md_is_badblock(struct badblocks *bb, sector_t s, int sectors,
7694                   sector_t *first_bad, int *bad_sectors)
7695{
7696        int hi;
7697        int lo = 0;
7698        u64 *p = bb->page;
7699        int rv = 0;
7700        sector_t target = s + sectors;
7701        unsigned seq;
7702
7703        if (bb->shift > 0) {
7704                /* round the start down, and the end up */
7705                s >>= bb->shift;
7706                target += (1<<bb->shift) - 1;
7707                target >>= bb->shift;
7708                sectors = target - s;
7709        }
7710        /* 'target' is now the first block after the bad range */
7711
7712retry:
7713        seq = read_seqbegin(&bb->lock);
7714
7715        hi = bb->count;
7716
7717        /* Binary search between lo and hi for 'target'
7718         * i.e. for the last range that starts before 'target'
7719         */
7720        /* INVARIANT: ranges before 'lo' and at-or-after 'hi'
7721         * are known not to be the last range before target.
7722         * VARIANT: hi-lo is the number of possible
7723         * ranges, and decreases until it reaches 1
7724         */
7725        while (hi - lo > 1) {
7726                int mid = (lo + hi) / 2;
7727                sector_t a = BB_OFFSET(p[mid]);
7728                if (a < target)
7729                        /* This could still be the one, earlier ranges
7730                         * could not. */
7731                        lo = mid;
7732                else
7733                        /* This and later ranges are definitely out. */
7734                        hi = mid;
7735        }
7736        /* 'lo' might be the last that started before target, but 'hi' isn't */
7737        if (hi > lo) {
7738                /* need to check all range that end after 's' to see if
7739                 * any are unacknowledged.
7740                 */
7741                while (lo >= 0 &&
7742                       BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) {
7743                        if (BB_OFFSET(p[lo]) < target) {
7744                                /* starts before the end, and finishes after
7745                                 * the start, so they must overlap
7746                                 */
7747                                if (rv != -1 && BB_ACK(p[lo]))
7748                                        rv = 1;
7749                                else
7750                                        rv = -1;
7751                                *first_bad = BB_OFFSET(p[lo]);
7752                                *bad_sectors = BB_LEN(p[lo]);
7753                        }
7754                        lo--;
7755                }
7756        }
7757
7758        if (read_seqretry(&bb->lock, seq))
7759                goto retry;
7760
7761        return rv;
7762}
7763EXPORT_SYMBOL_GPL(md_is_badblock);
7764
7765/*
7766 * Add a range of bad blocks to the table.
7767 * This might extend the table, or might contract it
7768 * if two adjacent ranges can be merged.
7769 * We binary-search to find the 'insertion' point, then
7770 * decide how best to handle it.
7771 */
7772static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
7773                            int acknowledged)
7774{
7775        u64 *p;
7776        int lo, hi;
7777        int rv = 1;
7778
7779        if (bb->shift < 0)
7780                /* badblocks are disabled */
7781                return 0;
7782
7783        if (bb->shift) {
7784                /* round the start down, and the end up */
7785                sector_t next = s + sectors;
7786                s >>= bb->shift;
7787                next += (1<<bb->shift) - 1;
7788                next >>= bb->shift;
7789                sectors = next - s;
7790        }
7791
7792        write_seqlock_irq(&bb->lock);
7793
7794        p = bb->page;
7795        lo = 0;
7796        hi = bb->count;
7797        /* Find the last range that starts at-or-before 's' */
7798        while (hi - lo > 1) {
7799                int mid = (lo + hi) / 2;
7800                sector_t a = BB_OFFSET(p[mid]);
7801                if (a <= s)
7802                        lo = mid;
7803                else
7804                        hi = mid;
7805        }
7806        if (hi > lo && BB_OFFSET(p[lo]) > s)
7807                hi = lo;
7808
7809        if (hi > lo) {
7810                /* we found a range that might merge with the start
7811                 * of our new range
7812                 */
7813                sector_t a = BB_OFFSET(p[lo]);
7814                sector_t e = a + BB_LEN(p[lo]);
7815                int ack = BB_ACK(p[lo]);
7816                if (e >= s) {
7817                        /* Yes, we can merge with a previous range */
7818                        if (s == a && s + sectors >= e)
7819                                /* new range covers old */
7820                                ack = acknowledged;
7821                        else
7822                                ack = ack && acknowledged;
7823
7824                        if (e < s + sectors)
7825                                e = s + sectors;
7826                        if (e - a <= BB_MAX_LEN) {
7827                                p[lo] = BB_MAKE(a, e-a, ack);
7828                                s = e;
7829                        } else {
7830                                /* does not all fit in one range,
7831                                 * make p[lo] maximal
7832                                 */
7833                                if (BB_LEN(p[lo]) != BB_MAX_LEN)
7834                                        p[lo] = BB_MAKE(a, BB_MAX_LEN, ack);
7835                                s = a + BB_MAX_LEN;
7836                        }
7837                        sectors = e - s;
7838                }
7839        }
7840        if (sectors && hi < bb->count) {
7841                /* 'hi' points to the first range that starts after 's'.
7842                 * Maybe we can merge with the start of that range */
7843                sector_t a = BB_OFFSET(p[hi]);
7844                sector_t e = a + BB_LEN(p[hi]);
7845                int ack = BB_ACK(p[hi]);
7846                if (a <= s + sectors) {
7847                        /* merging is possible */
7848                        if (e <= s + sectors) {
7849                                /* full overlap */
7850                                e = s + sectors;
7851                                ack = acknowledged;
7852                        } else
7853                                ack = ack && acknowledged;
7854
7855                        a = s;
7856                        if (e - a <= BB_MAX_LEN) {
7857                                p[hi] = BB_MAKE(a, e-a, ack);
7858                                s = e;
7859                        } else {
7860                                p[hi] = BB_MAKE(a, BB_MAX_LEN, ack);
7861                                s = a + BB_MAX_LEN;
7862                        }
7863                        sectors = e - s;
7864                        lo = hi;
7865                        hi++;
7866                }
7867        }
7868        if (sectors == 0 && hi < bb->count) {
7869                /* we might be able to combine lo and hi */
7870                /* Note: 's' is at the end of 'lo' */
7871                sector_t a = BB_OFFSET(p[hi]);
7872                int lolen = BB_LEN(p[lo]);
7873                int hilen = BB_LEN(p[hi]);
7874                int newlen = lolen + hilen - (s - a);
7875                if (s >= a && newlen < BB_MAX_LEN) {
7876                        /* yes, we can combine them */
7877                        int ack = BB_ACK(p[lo]) && BB_ACK(p[hi]);
7878                        p[lo] = BB_MAKE(BB_OFFSET(p[lo]), newlen, ack);
7879                        memmove(p + hi, p + hi + 1,
7880                                (bb->count - hi - 1) * 8);
7881                        bb->count--;
7882                }
7883        }
7884        while (sectors) {
7885                /* didn't merge (it all).
7886                 * Need to add a range just before 'hi' */
7887                if (bb->count >= MD_MAX_BADBLOCKS) {
7888                        /* No room for more */
7889                        rv = 0;
7890                        break;
7891                } else {
7892                        int this_sectors = sectors;
7893                        memmove(p + hi + 1, p + hi,
7894                                (bb->count - hi) * 8);
7895                        bb->count++;
7896
7897                        if (this_sectors > BB_MAX_LEN)
7898                                this_sectors = BB_MAX_LEN;
7899                        p[hi] = BB_MAKE(s, this_sectors, acknowledged);
7900                        sectors -= this_sectors;
7901                        s += this_sectors;
7902                }
7903        }
7904
7905        bb->changed = 1;
7906        if (!acknowledged)
7907                bb->unacked_exist = 1;
7908        write_sequnlock_irq(&bb->lock);
7909
7910        return rv;
7911}
7912
7913int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
7914                       int acknowledged)
7915{
7916        int rv = md_set_badblocks(&rdev->badblocks,
7917                                  s + rdev->data_offset, sectors, acknowledged);
7918        if (rv) {
7919                /* Make sure they get written out promptly */
7920                sysfs_notify_dirent_safe(rdev->sysfs_state);
7921                set_bit(MD_CHANGE_CLEAN, &rdev->mddev->flags);
7922                md_wakeup_thread(rdev->mddev->thread);
7923        }
7924        return rv;
7925}
7926EXPORT_SYMBOL_GPL(rdev_set_badblocks);
7927
7928/*
7929 * Remove a range of bad blocks from the table.
7930 * This may involve extending the table if we spilt a region,
7931 * but it must not fail.  So if the table becomes full, we just
7932 * drop the remove request.
7933 */
7934static int md_clear_badblocks(struct badblocks *bb, sector_t s, int sectors)
7935{
7936        u64 *p;
7937        int lo, hi;
7938        sector_t target = s + sectors;
7939        int rv = 0;
7940
7941        if (bb->shift > 0) {
7942                /* When clearing we round the start up and the end down.
7943                 * This should not matter as the shift should align with
7944                 * the block size and no rounding should ever be needed.
7945                 * However it is better the think a block is bad when it
7946                 * isn't than to think a block is not bad when it is.
7947                 */
7948                s += (1<<bb->shift) - 1;
7949                s >>= bb->shift;
7950                target >>= bb->shift;
7951                sectors = target - s;
7952        }
7953
7954        write_seqlock_irq(&bb->lock);
7955
7956        p = bb->page;
7957        lo = 0;
7958        hi = bb->count;
7959        /* Find the last range that starts before 'target' */
7960        while (hi - lo > 1) {
7961                int mid = (lo + hi) / 2;
7962                sector_t a = BB_OFFSET(p[mid]);
7963                if (a < target)
7964                        lo = mid;
7965                else
7966                        hi = mid;
7967        }
7968        if (hi > lo) {
7969                /* p[lo] is the last range that could overlap the
7970                 * current range.  Earlier ranges could also overlap,
7971                 * but only this one can overlap the end of the range.
7972                 */
7973                if (BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > target) {
7974                        /* Partial overlap, leave the tail of this range */
7975                        int ack = BB_ACK(p[lo]);
7976                        sector_t a = BB_OFFSET(p[lo]);
7977                        sector_t end = a + BB_LEN(p[lo]);
7978
7979                        if (a < s) {
7980                                /* we need to split this range */
7981                                if (bb->count >= MD_MAX_BADBLOCKS) {
7982                                        rv = 0;
7983                                        goto out;
7984                                }
7985                                memmove(p+lo+1, p+lo, (bb->count - lo) * 8);
7986                                bb->count++;
7987                                p[lo] = BB_MAKE(a, s-a, ack);
7988                                lo++;
7989                        }
7990                        p[lo] = BB_MAKE(target, end - target, ack);
7991                        /* there is no longer an overlap */
7992                        hi = lo;
7993                        lo--;
7994                }
7995                while (lo >= 0 &&
7996                       BB_OFFSET(p[lo]) + BB_LEN(p[lo]) > s) {
7997                        /* This range does overlap */
7998                        if (BB_OFFSET(p[lo]) < s) {
7999                                /* Keep the early parts of this range. */
8000                                int ack = BB_ACK(p[lo]);
8001                                sector_t start = BB_OFFSET(p[lo]);
8002                                p[lo] = BB_MAKE(start, s - start, ack);
8003                                /* now low doesn't overlap, so.. */
8004                                break;
8005                        }
8006                        lo--;
8007                }
8008                /* 'lo' is strictly before, 'hi' is strictly after,
8009                 * anything between needs to be discarded
8010                 */
8011                if (hi - lo > 1) {
8012                        memmove(p+lo+1, p+hi, (bb->count - hi) * 8);
8013                        bb->count -= (hi - lo - 1);
8014                }
8015        }
8016
8017        bb->changed = 1;
8018out:
8019        write_sequnlock_irq(&bb->lock);
8020        return rv;
8021}
8022
8023int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors)
8024{
8025        return md_clear_badblocks(&rdev->badblocks,
8026                                  s + rdev->data_offset,
8027                                  sectors);
8028}
8029EXPORT_SYMBOL_GPL(rdev_clear_badblocks);
8030
8031/*
8032 * Acknowledge all bad blocks in a list.
8033 * This only succeeds if ->changed is clear.  It is used by
8034 * in-kernel metadata updates
8035 */
8036void md_ack_all_badblocks(struct badblocks *bb)
8037{
8038        if (bb->page == NULL || bb->changed)
8039                /* no point even trying */
8040                return;
8041        write_seqlock_irq(&bb->lock);
8042
8043        if (bb->changed == 0) {
8044                u64 *p = bb->page;
8045                int i;
8046                for (i = 0; i < bb->count ; i++) {
8047                        if (!BB_ACK(p[i])) {
8048                                sector_t start = BB_OFFSET(p[i]);
8049                                int len = BB_LEN(p[i]);
8050                                p[i] = BB_MAKE(start, len, 1);
8051                        }
8052                }
8053                bb->unacked_exist = 0;
8054        }
8055        write_sequnlock_irq(&bb->lock);
8056}
8057EXPORT_SYMBOL_GPL(md_ack_all_badblocks);
8058
8059/* sysfs access to bad-blocks list.
8060 * We present two files.
8061 * 'bad-blocks' lists sector numbers and lengths of ranges that
8062 *    are recorded as bad.  The list is truncated to fit within
8063 *    the one-page limit of sysfs.
8064 *    Writing "sector length" to this file adds an acknowledged
8065 *    bad block list.
8066 * 'unacknowledged-bad-blocks' lists bad blocks that have not yet
8067 *    been acknowledged.  Writing to this file adds bad blocks
8068 *    without acknowledging them.  This is largely for testing.
8069 */
8070
8071static ssize_t
8072badblocks_show(struct badblocks *bb, char *page, int unack)
8073{
8074        size_t len;
8075        int i;
8076        u64 *p = bb->page;
8077        unsigned seq;
8078
8079        if (bb->shift < 0)
8080                return 0;
8081
8082retry:
8083        seq = read_seqbegin(&bb->lock);
8084
8085        len = 0;
8086        i = 0;
8087
8088        while (len < PAGE_SIZE && i < bb->count) {
8089                sector_t s = BB_OFFSET(p[i]);
8090                unsigned int length = BB_LEN(p[i]);
8091                int ack = BB_ACK(p[i]);
8092                i++;
8093
8094                if (unack && ack)
8095                        continue;
8096
8097                len += snprintf(page+len, PAGE_SIZE-len, "%llu %u\n",
8098                                (unsigned long long)s << bb->shift,
8099                                length << bb->shift);
8100        }
8101        if (unack && len == 0)
8102                bb->unacked_exist = 0;
8103
8104        if (read_seqretry(&bb->lock, seq))
8105                goto retry;
8106
8107        return len;
8108}
8109
8110#define DO_DEBUG 1
8111
8112static ssize_t
8113badblocks_store(struct badblocks *bb, const char *page, size_t len, int unack)
8114{
8115        unsigned long long sector;
8116        int length;
8117        char newline;
8118#ifdef DO_DEBUG
8119        /* Allow clearing via sysfs *only* for testing/debugging.
8120         * Normally only a successful write may clear a badblock
8121         */
8122        int clear = 0;
8123        if (page[0] == '-') {
8124                clear = 1;
8125                page++;
8126        }
8127#endif /* DO_DEBUG */
8128
8129        switch (sscanf(page, "%llu %d%c", &sector, &length, &newline)) {
8130        case 3:
8131                if (newline != '\n')
8132                        return -EINVAL;
8133        case 2:
8134                if (length <= 0)
8135                        return -EINVAL;
8136                break;
8137        default:
8138                return -EINVAL;
8139        }
8140
8141#ifdef DO_DEBUG
8142        if (clear) {
8143                md_clear_badblocks(bb, sector, length);
8144                return len;
8145        }
8146#endif /* DO_DEBUG */
8147        if (md_set_badblocks(bb, sector, length, !unack))
8148                return len;
8149        else
8150                return -ENOSPC;
8151}
8152
8153static int md_notify_reboot(struct notifier_block *this,
8154                            unsigned long code, void *x)
8155{
8156        struct list_head *tmp;
8157        struct mddev *mddev;
8158        int need_delay = 0;
8159
8160        if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
8161
8162                printk(KERN_INFO "md: stopping all md devices.\n");
8163
8164                for_each_mddev(mddev, tmp) {
8165                        if (mddev_trylock(mddev)) {
8166                                /* Force a switch to readonly even array
8167                                 * appears to still be in use.  Hence
8168                                 * the '100'.
8169                                 */
8170                                md_set_readonly(mddev, 100);
8171                                mddev_unlock(mddev);
8172                        }
8173                        need_delay = 1;
8174                }
8175                /*
8176                 * certain more exotic SCSI devices are known to be
8177                 * volatile wrt too early system reboots. While the
8178                 * right place to handle this issue is the given
8179                 * driver, we do want to have a safe RAID driver ...
8180                 */
8181                if (need_delay)
8182                        mdelay(1000*1);
8183        }
8184        return NOTIFY_DONE;
8185}
8186
8187static struct notifier_block md_notifier = {
8188        .notifier_call  = md_notify_reboot,
8189        .next           = NULL,
8190        .priority       = INT_MAX, /* before any real devices */
8191};
8192
8193static void md_geninit(void)
8194{
8195        pr_debug("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
8196
8197        proc_create("mdstat", S_IRUGO, NULL, &md_seq_fops);
8198}
8199
8200static int __init md_init(void)
8201{
8202        int ret = -ENOMEM;
8203
8204        md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM, 0);
8205        if (!md_wq)
8206                goto err_wq;
8207
8208        md_misc_wq = alloc_workqueue("md_misc", 0, 0);
8209        if (!md_misc_wq)
8210                goto err_misc_wq;
8211
8212        if ((ret = register_blkdev(MD_MAJOR, "md")) < 0)
8213                goto err_md;
8214
8215        if ((ret = register_blkdev(0, "mdp")) < 0)
8216                goto err_mdp;
8217        mdp_major = ret;
8218
8219        blk_register_region(MKDEV(MD_MAJOR, 0), 1UL<<MINORBITS, THIS_MODULE,
8220                            md_probe, NULL, NULL);
8221        blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE,
8222                            md_probe, NULL, NULL);
8223
8224        register_reboot_notifier(&md_notifier);
8225        raid_table_header = register_sysctl_table(raid_root_table);
8226
8227        md_geninit();
8228        return 0;
8229
8230err_mdp:
8231        unregister_blkdev(MD_MAJOR, "md");
8232err_md:
8233        destroy_workqueue(md_misc_wq);
8234err_misc_wq:
8235        destroy_workqueue(md_wq);
8236err_wq:
8237        return ret;
8238}
8239
8240#ifndef MODULE
8241
8242/*
8243 * Searches all registered partitions for autorun RAID arrays
8244 * at boot time.
8245 */
8246
8247static LIST_HEAD(all_detected_devices);
8248struct detected_devices_node {
8249        struct list_head list;
8250        dev_t dev;
8251};
8252
8253void md_autodetect_dev(dev_t dev)
8254{
8255        struct detected_devices_node *node_detected_dev;
8256
8257        node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
8258        if (node_detected_dev) {
8259                node_detected_dev->dev = dev;
8260                list_add_tail(&node_detected_dev->list, &all_detected_devices);
8261        } else {
8262                printk(KERN_CRIT "md: md_autodetect_dev: kzalloc failed"
8263                        ", skipping dev(%d,%d)\n", MAJOR(dev), MINOR(dev));
8264        }
8265}
8266
8267
8268static void autostart_arrays(int part)
8269{
8270        struct md_rdev *rdev;
8271        struct detected_devices_node *node_detected_dev;
8272        dev_t dev;
8273        int i_scanned, i_passed;
8274
8275        i_scanned = 0;
8276        i_passed = 0;
8277
8278        printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
8279
8280        while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
8281                i_scanned++;
8282                node_detected_dev = list_entry(all_detected_devices.next,
8283                                        struct detected_devices_node, list);
8284                list_del(&node_detected_dev->list);
8285                dev = node_detected_dev->dev;
8286                kfree(node_detected_dev);
8287                rdev = md_import_device(dev,0, 90);
8288                if (IS_ERR(rdev))
8289                        continue;
8290
8291                if (test_bit(Faulty, &rdev->flags)) {
8292                        MD_BUG();
8293                        continue;
8294                }
8295                set_bit(AutoDetected, &rdev->flags);
8296                list_add(&rdev->same_set, &pending_raid_disks);
8297                i_passed++;
8298        }
8299
8300        printk(KERN_INFO "md: Scanned %d and added %d devices.\n",
8301                                                i_scanned, i_passed);
8302
8303        autorun_devices(part);
8304}
8305
8306#endif /* !MODULE */
8307
8308static __exit void md_exit(void)
8309{
8310        struct mddev *mddev;
8311        struct list_head *tmp;
8312
8313        blk_unregister_region(MKDEV(MD_MAJOR,0), 1U << MINORBITS);
8314        blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS);
8315
8316        unregister_blkdev(MD_MAJOR,"md");
8317        unregister_blkdev(mdp_major, "mdp");
8318        unregister_reboot_notifier(&md_notifier);
8319        unregister_sysctl_table(raid_table_header);
8320        remove_proc_entry("mdstat", NULL);
8321        for_each_mddev(mddev, tmp) {
8322                export_array(mddev);
8323                mddev->hold_active = 0;
8324        }
8325        destroy_workqueue(md_misc_wq);
8326        destroy_workqueue(md_wq);
8327}
8328
8329subsys_initcall(md_init);
8330module_exit(md_exit)
8331
8332static int get_ro(char *buffer, struct kernel_param *kp)
8333{
8334        return sprintf(buffer, "%d", start_readonly);
8335}
8336static int set_ro(const char *val, struct kernel_param *kp)
8337{
8338        char *e;
8339        int num = simple_strtoul(val, &e, 10);
8340        if (*val && (*e == '\0' || *e == '\n')) {
8341                start_readonly = num;
8342                return 0;
8343        }
8344        return -EINVAL;
8345}
8346
8347module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
8348module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
8349
8350module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR);
8351
8352EXPORT_SYMBOL(register_md_personality);
8353EXPORT_SYMBOL(unregister_md_personality);
8354EXPORT_SYMBOL(md_error);
8355EXPORT_SYMBOL(md_done_sync);
8356EXPORT_SYMBOL(md_write_start);
8357EXPORT_SYMBOL(md_write_end);
8358EXPORT_SYMBOL(md_register_thread);
8359EXPORT_SYMBOL(md_unregister_thread);
8360EXPORT_SYMBOL(md_wakeup_thread);
8361EXPORT_SYMBOL(md_check_recovery);
8362MODULE_LICENSE("GPL");
8363MODULE_DESCRIPTION("MD RAID framework");
8364MODULE_ALIAS("md");
8365MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);
8366