linux/fs/nfs/flexfilelayout/flexfilelayout.c
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   1/*
   2 * Module for pnfs flexfile layout driver.
   3 *
   4 * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5 *
   6 * Tao Peng <bergwolf@primarydata.com>
   7 */
   8
   9#include <linux/nfs_fs.h>
  10#include <linux/nfs_page.h>
  11#include <linux/module.h>
  12
  13#include <linux/sunrpc/metrics.h>
  14
  15#include "flexfilelayout.h"
  16#include "../nfs4session.h"
  17#include "../nfs4idmap.h"
  18#include "../internal.h"
  19#include "../delegation.h"
  20#include "../nfs4trace.h"
  21#include "../iostat.h"
  22#include "../nfs.h"
  23#include "../nfs42.h"
  24
  25#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  26
  27#define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  28
  29static struct group_info        *ff_zero_group;
  30
  31static struct pnfs_layout_hdr *
  32ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  33{
  34        struct nfs4_flexfile_layout *ffl;
  35
  36        ffl = kzalloc(sizeof(*ffl), gfp_flags);
  37        if (ffl) {
  38                INIT_LIST_HEAD(&ffl->error_list);
  39                INIT_LIST_HEAD(&ffl->mirrors);
  40                ffl->last_report_time = ktime_get();
  41                return &ffl->generic_hdr;
  42        } else
  43                return NULL;
  44}
  45
  46static void
  47ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  48{
  49        struct nfs4_ff_layout_ds_err *err, *n;
  50
  51        list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  52                                 list) {
  53                list_del(&err->list);
  54                kfree(err);
  55        }
  56        kfree(FF_LAYOUT_FROM_HDR(lo));
  57}
  58
  59static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  60{
  61        __be32 *p;
  62
  63        p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  64        if (unlikely(p == NULL))
  65                return -ENOBUFS;
  66        stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  67        memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  68        dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  69                p[0], p[1], p[2], p[3]);
  70        return 0;
  71}
  72
  73static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  74{
  75        __be32 *p;
  76
  77        p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  78        if (unlikely(!p))
  79                return -ENOBUFS;
  80        memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  81        nfs4_print_deviceid(devid);
  82        return 0;
  83}
  84
  85static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  86{
  87        __be32 *p;
  88
  89        p = xdr_inline_decode(xdr, 4);
  90        if (unlikely(!p))
  91                return -ENOBUFS;
  92        fh->size = be32_to_cpup(p++);
  93        if (fh->size > sizeof(struct nfs_fh)) {
  94                printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
  95                       fh->size);
  96                return -EOVERFLOW;
  97        }
  98        /* fh.data */
  99        p = xdr_inline_decode(xdr, fh->size);
 100        if (unlikely(!p))
 101                return -ENOBUFS;
 102        memcpy(&fh->data, p, fh->size);
 103        dprintk("%s: fh len %d\n", __func__, fh->size);
 104
 105        return 0;
 106}
 107
 108/*
 109 * Currently only stringified uids and gids are accepted.
 110 * I.e., kerberos is not supported to the DSes, so no pricipals.
 111 *
 112 * That means that one common function will suffice, but when
 113 * principals are added, this should be split to accomodate
 114 * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 115 */
 116static int
 117decode_name(struct xdr_stream *xdr, u32 *id)
 118{
 119        __be32 *p;
 120        int len;
 121
 122        /* opaque_length(4)*/
 123        p = xdr_inline_decode(xdr, 4);
 124        if (unlikely(!p))
 125                return -ENOBUFS;
 126        len = be32_to_cpup(p++);
 127        if (len < 0)
 128                return -EINVAL;
 129
 130        dprintk("%s: len %u\n", __func__, len);
 131
 132        /* opaque body */
 133        p = xdr_inline_decode(xdr, len);
 134        if (unlikely(!p))
 135                return -ENOBUFS;
 136
 137        if (!nfs_map_string_to_numeric((char *)p, len, id))
 138                return -EINVAL;
 139
 140        return 0;
 141}
 142
 143static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 144                const struct nfs4_ff_layout_mirror *m2)
 145{
 146        int i, j;
 147
 148        if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 149                return false;
 150        for (i = 0; i < m1->fh_versions_cnt; i++) {
 151                bool found_fh = false;
 152                for (j = 0; j < m2->fh_versions_cnt; j++) {
 153                        if (nfs_compare_fh(&m1->fh_versions[i],
 154                                        &m2->fh_versions[j]) == 0) {
 155                                found_fh = true;
 156                                break;
 157                        }
 158                }
 159                if (!found_fh)
 160                        return false;
 161        }
 162        return true;
 163}
 164
 165static struct nfs4_ff_layout_mirror *
 166ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 167                struct nfs4_ff_layout_mirror *mirror)
 168{
 169        struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 170        struct nfs4_ff_layout_mirror *pos;
 171        struct inode *inode = lo->plh_inode;
 172
 173        spin_lock(&inode->i_lock);
 174        list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 175                if (mirror->mirror_ds != pos->mirror_ds)
 176                        continue;
 177                if (!ff_mirror_match_fh(mirror, pos))
 178                        continue;
 179                if (atomic_inc_not_zero(&pos->ref)) {
 180                        spin_unlock(&inode->i_lock);
 181                        return pos;
 182                }
 183        }
 184        list_add(&mirror->mirrors, &ff_layout->mirrors);
 185        mirror->layout = lo;
 186        spin_unlock(&inode->i_lock);
 187        return mirror;
 188}
 189
 190static void
 191ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 192{
 193        struct inode *inode;
 194        if (mirror->layout == NULL)
 195                return;
 196        inode = mirror->layout->plh_inode;
 197        spin_lock(&inode->i_lock);
 198        list_del(&mirror->mirrors);
 199        spin_unlock(&inode->i_lock);
 200        mirror->layout = NULL;
 201}
 202
 203static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 204{
 205        struct nfs4_ff_layout_mirror *mirror;
 206
 207        mirror = kzalloc(sizeof(*mirror), gfp_flags);
 208        if (mirror != NULL) {
 209                spin_lock_init(&mirror->lock);
 210                atomic_set(&mirror->ref, 1);
 211                INIT_LIST_HEAD(&mirror->mirrors);
 212        }
 213        return mirror;
 214}
 215
 216static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 217{
 218        struct rpc_cred *cred;
 219
 220        ff_layout_remove_mirror(mirror);
 221        kfree(mirror->fh_versions);
 222        cred = rcu_access_pointer(mirror->ro_cred);
 223        if (cred)
 224                put_rpccred(cred);
 225        cred = rcu_access_pointer(mirror->rw_cred);
 226        if (cred)
 227                put_rpccred(cred);
 228        nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 229        kfree(mirror);
 230}
 231
 232static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 233{
 234        if (mirror != NULL && atomic_dec_and_test(&mirror->ref))
 235                ff_layout_free_mirror(mirror);
 236}
 237
 238static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 239{
 240        int i;
 241
 242        if (fls->mirror_array) {
 243                for (i = 0; i < fls->mirror_array_cnt; i++) {
 244                        /* normally mirror_ds is freed in
 245                         * .free_deviceid_node but we still do it here
 246                         * for .alloc_lseg error path */
 247                        ff_layout_put_mirror(fls->mirror_array[i]);
 248                }
 249                kfree(fls->mirror_array);
 250                fls->mirror_array = NULL;
 251        }
 252}
 253
 254static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 255{
 256        int ret = 0;
 257
 258        dprintk("--> %s\n", __func__);
 259
 260        /* FIXME: remove this check when layout segment support is added */
 261        if (lgr->range.offset != 0 ||
 262            lgr->range.length != NFS4_MAX_UINT64) {
 263                dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 264                        __func__);
 265                ret = -EINVAL;
 266        }
 267
 268        dprintk("--> %s returns %d\n", __func__, ret);
 269        return ret;
 270}
 271
 272static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 273{
 274        if (fls) {
 275                ff_layout_free_mirror_array(fls);
 276                kfree(fls);
 277        }
 278}
 279
 280static bool
 281ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 282                const struct pnfs_layout_range *l2)
 283{
 284        u64 end1, end2;
 285
 286        if (l1->iomode != l2->iomode)
 287                return l1->iomode != IOMODE_READ;
 288        end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 289        end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 290        if (end1 < l2->offset)
 291                return false;
 292        if (end2 < l1->offset)
 293                return true;
 294        return l2->offset <= l1->offset;
 295}
 296
 297static bool
 298ff_lseg_merge(struct pnfs_layout_segment *new,
 299                struct pnfs_layout_segment *old)
 300{
 301        u64 new_end, old_end;
 302
 303        if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 304                return false;
 305        if (new->pls_range.iomode != old->pls_range.iomode)
 306                return false;
 307        old_end = pnfs_calc_offset_end(old->pls_range.offset,
 308                        old->pls_range.length);
 309        if (old_end < new->pls_range.offset)
 310                return false;
 311        new_end = pnfs_calc_offset_end(new->pls_range.offset,
 312                        new->pls_range.length);
 313        if (new_end < old->pls_range.offset)
 314                return false;
 315
 316        /* Mergeable: copy info from 'old' to 'new' */
 317        if (new_end < old_end)
 318                new_end = old_end;
 319        if (new->pls_range.offset < old->pls_range.offset)
 320                new->pls_range.offset = old->pls_range.offset;
 321        new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 322                        new_end);
 323        if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 324                set_bit(NFS_LSEG_ROC, &new->pls_flags);
 325        return true;
 326}
 327
 328static void
 329ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 330                struct pnfs_layout_segment *lseg,
 331                struct list_head *free_me)
 332{
 333        pnfs_generic_layout_insert_lseg(lo, lseg,
 334                        ff_lseg_range_is_after,
 335                        ff_lseg_merge,
 336                        free_me);
 337}
 338
 339static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 340{
 341        int i, j;
 342
 343        for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 344                for (j = i + 1; j < fls->mirror_array_cnt; j++)
 345                        if (fls->mirror_array[i]->efficiency <
 346                            fls->mirror_array[j]->efficiency)
 347                                swap(fls->mirror_array[i],
 348                                     fls->mirror_array[j]);
 349        }
 350}
 351
 352static void ff_layout_mark_devices_valid(struct nfs4_ff_layout_segment *fls)
 353{
 354        struct nfs4_deviceid_node *node;
 355        int i;
 356
 357        if (!(fls->flags & FF_FLAGS_NO_IO_THRU_MDS))
 358                return;
 359        for (i = 0; i < fls->mirror_array_cnt; i++) {
 360                node = &fls->mirror_array[i]->mirror_ds->id_node;
 361                clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
 362        }
 363}
 364
 365static struct pnfs_layout_segment *
 366ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 367                     struct nfs4_layoutget_res *lgr,
 368                     gfp_t gfp_flags)
 369{
 370        struct pnfs_layout_segment *ret;
 371        struct nfs4_ff_layout_segment *fls = NULL;
 372        struct xdr_stream stream;
 373        struct xdr_buf buf;
 374        struct page *scratch;
 375        u64 stripe_unit;
 376        u32 mirror_array_cnt;
 377        __be32 *p;
 378        int i, rc;
 379
 380        dprintk("--> %s\n", __func__);
 381        scratch = alloc_page(gfp_flags);
 382        if (!scratch)
 383                return ERR_PTR(-ENOMEM);
 384
 385        xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 386                              lgr->layoutp->len);
 387        xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 388
 389        /* stripe unit and mirror_array_cnt */
 390        rc = -EIO;
 391        p = xdr_inline_decode(&stream, 8 + 4);
 392        if (!p)
 393                goto out_err_free;
 394
 395        p = xdr_decode_hyper(p, &stripe_unit);
 396        mirror_array_cnt = be32_to_cpup(p++);
 397        dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 398                stripe_unit, mirror_array_cnt);
 399
 400        if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 401            mirror_array_cnt == 0)
 402                goto out_err_free;
 403
 404        rc = -ENOMEM;
 405        fls = kzalloc(sizeof(*fls), gfp_flags);
 406        if (!fls)
 407                goto out_err_free;
 408
 409        fls->mirror_array_cnt = mirror_array_cnt;
 410        fls->stripe_unit = stripe_unit;
 411        fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 412                                    sizeof(fls->mirror_array[0]), gfp_flags);
 413        if (fls->mirror_array == NULL)
 414                goto out_err_free;
 415
 416        for (i = 0; i < fls->mirror_array_cnt; i++) {
 417                struct nfs4_ff_layout_mirror *mirror;
 418                struct nfs4_deviceid devid;
 419                struct nfs4_deviceid_node *idnode;
 420                struct auth_cred acred = { .group_info = ff_zero_group };
 421                struct rpc_cred __rcu *cred;
 422                u32 ds_count, fh_count, id;
 423                int j;
 424
 425                rc = -EIO;
 426                p = xdr_inline_decode(&stream, 4);
 427                if (!p)
 428                        goto out_err_free;
 429                ds_count = be32_to_cpup(p);
 430
 431                /* FIXME: allow for striping? */
 432                if (ds_count != 1)
 433                        goto out_err_free;
 434
 435                fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 436                if (fls->mirror_array[i] == NULL) {
 437                        rc = -ENOMEM;
 438                        goto out_err_free;
 439                }
 440
 441                fls->mirror_array[i]->ds_count = ds_count;
 442
 443                /* deviceid */
 444                rc = decode_deviceid(&stream, &devid);
 445                if (rc)
 446                        goto out_err_free;
 447
 448                idnode = nfs4_find_get_deviceid(NFS_SERVER(lh->plh_inode),
 449                                                &devid, lh->plh_lc_cred,
 450                                                gfp_flags);
 451                /*
 452                 * upon success, mirror_ds is allocated by previous
 453                 * getdeviceinfo, or newly by .alloc_deviceid_node
 454                 * nfs4_find_get_deviceid failure is indeed getdeviceinfo falure
 455                 */
 456                if (idnode)
 457                        fls->mirror_array[i]->mirror_ds =
 458                                FF_LAYOUT_MIRROR_DS(idnode);
 459                else
 460                        goto out_err_free;
 461
 462                /* efficiency */
 463                rc = -EIO;
 464                p = xdr_inline_decode(&stream, 4);
 465                if (!p)
 466                        goto out_err_free;
 467                fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 468
 469                /* stateid */
 470                rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 471                if (rc)
 472                        goto out_err_free;
 473
 474                /* fh */
 475                p = xdr_inline_decode(&stream, 4);
 476                if (!p)
 477                        goto out_err_free;
 478                fh_count = be32_to_cpup(p);
 479
 480                fls->mirror_array[i]->fh_versions =
 481                        kzalloc(fh_count * sizeof(struct nfs_fh),
 482                                gfp_flags);
 483                if (fls->mirror_array[i]->fh_versions == NULL) {
 484                        rc = -ENOMEM;
 485                        goto out_err_free;
 486                }
 487
 488                for (j = 0; j < fh_count; j++) {
 489                        rc = decode_nfs_fh(&stream,
 490                                           &fls->mirror_array[i]->fh_versions[j]);
 491                        if (rc)
 492                                goto out_err_free;
 493                }
 494
 495                fls->mirror_array[i]->fh_versions_cnt = fh_count;
 496
 497                /* user */
 498                rc = decode_name(&stream, &id);
 499                if (rc)
 500                        goto out_err_free;
 501
 502                acred.uid = make_kuid(&init_user_ns, id);
 503
 504                /* group */
 505                rc = decode_name(&stream, &id);
 506                if (rc)
 507                        goto out_err_free;
 508
 509                acred.gid = make_kgid(&init_user_ns, id);
 510
 511                /* find the cred for it */
 512                rcu_assign_pointer(cred, rpc_lookup_generic_cred(&acred, 0, gfp_flags));
 513                if (IS_ERR(cred)) {
 514                        rc = PTR_ERR(cred);
 515                        goto out_err_free;
 516                }
 517
 518                if (lgr->range.iomode == IOMODE_READ)
 519                        rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 520                else
 521                        rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 522
 523                mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 524                if (mirror != fls->mirror_array[i]) {
 525                        /* swap cred ptrs so free_mirror will clean up old */
 526                        if (lgr->range.iomode == IOMODE_READ) {
 527                                cred = xchg(&mirror->ro_cred, cred);
 528                                rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 529                        } else {
 530                                cred = xchg(&mirror->rw_cred, cred);
 531                                rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 532                        }
 533                        ff_layout_free_mirror(fls->mirror_array[i]);
 534                        fls->mirror_array[i] = mirror;
 535                }
 536
 537                dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 538                        lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 539                        from_kuid(&init_user_ns, acred.uid),
 540                        from_kgid(&init_user_ns, acred.gid));
 541        }
 542
 543        p = xdr_inline_decode(&stream, 4);
 544        if (!p)
 545                goto out_sort_mirrors;
 546        fls->flags = be32_to_cpup(p);
 547
 548        p = xdr_inline_decode(&stream, 4);
 549        if (!p)
 550                goto out_sort_mirrors;
 551        for (i=0; i < fls->mirror_array_cnt; i++)
 552                fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 553
 554out_sort_mirrors:
 555        ff_layout_sort_mirrors(fls);
 556        rc = ff_layout_check_layout(lgr);
 557        if (rc)
 558                goto out_err_free;
 559        ff_layout_mark_devices_valid(fls);
 560
 561        ret = &fls->generic_hdr;
 562        dprintk("<-- %s (success)\n", __func__);
 563out_free_page:
 564        __free_page(scratch);
 565        return ret;
 566out_err_free:
 567        _ff_layout_free_lseg(fls);
 568        ret = ERR_PTR(rc);
 569        dprintk("<-- %s (%d)\n", __func__, rc);
 570        goto out_free_page;
 571}
 572
 573static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 574{
 575        struct pnfs_layout_segment *lseg;
 576
 577        list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 578                if (lseg->pls_range.iomode == IOMODE_RW)
 579                        return true;
 580
 581        return false;
 582}
 583
 584static void
 585ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 586{
 587        struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 588
 589        dprintk("--> %s\n", __func__);
 590
 591        if (lseg->pls_range.iomode == IOMODE_RW) {
 592                struct nfs4_flexfile_layout *ffl;
 593                struct inode *inode;
 594
 595                ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 596                inode = ffl->generic_hdr.plh_inode;
 597                spin_lock(&inode->i_lock);
 598                if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 599                        ffl->commit_info.nbuckets = 0;
 600                        kfree(ffl->commit_info.buckets);
 601                        ffl->commit_info.buckets = NULL;
 602                }
 603                spin_unlock(&inode->i_lock);
 604        }
 605        _ff_layout_free_lseg(fls);
 606}
 607
 608/* Return 1 until we have multiple lsegs support */
 609static int
 610ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 611{
 612        return 1;
 613}
 614
 615static void
 616nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 617{
 618        /* first IO request? */
 619        if (atomic_inc_return(&timer->n_ops) == 1) {
 620                timer->start_time = now;
 621        }
 622}
 623
 624static ktime_t
 625nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 626{
 627        ktime_t start;
 628
 629        if (atomic_dec_return(&timer->n_ops) < 0)
 630                WARN_ON_ONCE(1);
 631
 632        start = timer->start_time;
 633        timer->start_time = now;
 634        return ktime_sub(now, start);
 635}
 636
 637static bool
 638nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 639                            struct nfs4_ff_layoutstat *layoutstat,
 640                            ktime_t now)
 641{
 642        static const ktime_t notime = {0};
 643        s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 644        struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 645
 646        nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 647        if (ktime_equal(mirror->start_time, notime))
 648                mirror->start_time = now;
 649        if (mirror->report_interval != 0)
 650                report_interval = (s64)mirror->report_interval * 1000LL;
 651        else if (layoutstats_timer != 0)
 652                report_interval = (s64)layoutstats_timer * 1000LL;
 653        if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 654                        report_interval) {
 655                ffl->last_report_time = now;
 656                return true;
 657        }
 658
 659        return false;
 660}
 661
 662static void
 663nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 664                __u64 requested)
 665{
 666        struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 667
 668        iostat->ops_requested++;
 669        iostat->bytes_requested += requested;
 670}
 671
 672static void
 673nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 674                __u64 requested,
 675                __u64 completed,
 676                ktime_t time_completed,
 677                ktime_t time_started)
 678{
 679        struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 680        ktime_t completion_time = ktime_sub(time_completed, time_started);
 681        ktime_t timer;
 682
 683        iostat->ops_completed++;
 684        iostat->bytes_completed += completed;
 685        iostat->bytes_not_delivered += requested - completed;
 686
 687        timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 688        iostat->total_busy_time =
 689                        ktime_add(iostat->total_busy_time, timer);
 690        iostat->aggregate_completion_time =
 691                        ktime_add(iostat->aggregate_completion_time,
 692                                        completion_time);
 693}
 694
 695static void
 696nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 697                struct nfs4_ff_layout_mirror *mirror,
 698                __u64 requested, ktime_t now)
 699{
 700        bool report;
 701
 702        spin_lock(&mirror->lock);
 703        report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 704        nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 705        spin_unlock(&mirror->lock);
 706
 707        if (report)
 708                pnfs_report_layoutstat(inode, GFP_KERNEL);
 709}
 710
 711static void
 712nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 713                struct nfs4_ff_layout_mirror *mirror,
 714                __u64 requested,
 715                __u64 completed)
 716{
 717        spin_lock(&mirror->lock);
 718        nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 719                        requested, completed,
 720                        ktime_get(), task->tk_start);
 721        spin_unlock(&mirror->lock);
 722}
 723
 724static void
 725nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 726                struct nfs4_ff_layout_mirror *mirror,
 727                __u64 requested, ktime_t now)
 728{
 729        bool report;
 730
 731        spin_lock(&mirror->lock);
 732        report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 733        nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 734        spin_unlock(&mirror->lock);
 735
 736        if (report)
 737                pnfs_report_layoutstat(inode, GFP_NOIO);
 738}
 739
 740static void
 741nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 742                struct nfs4_ff_layout_mirror *mirror,
 743                __u64 requested,
 744                __u64 completed,
 745                enum nfs3_stable_how committed)
 746{
 747        if (committed == NFS_UNSTABLE)
 748                requested = completed = 0;
 749
 750        spin_lock(&mirror->lock);
 751        nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 752                        requested, completed, ktime_get(), task->tk_start);
 753        spin_unlock(&mirror->lock);
 754}
 755
 756static int
 757ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 758                            struct nfs_commit_info *cinfo,
 759                            gfp_t gfp_flags)
 760{
 761        struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 762        struct pnfs_commit_bucket *buckets;
 763        int size;
 764
 765        if (cinfo->ds->nbuckets != 0) {
 766                /* This assumes there is only one RW lseg per file.
 767                 * To support multiple lseg per file, we need to
 768                 * change struct pnfs_commit_bucket to allow dynamic
 769                 * increasing nbuckets.
 770                 */
 771                return 0;
 772        }
 773
 774        size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 775
 776        buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 777                          gfp_flags);
 778        if (!buckets)
 779                return -ENOMEM;
 780        else {
 781                int i;
 782
 783                spin_lock(&cinfo->inode->i_lock);
 784                if (cinfo->ds->nbuckets != 0)
 785                        kfree(buckets);
 786                else {
 787                        cinfo->ds->buckets = buckets;
 788                        cinfo->ds->nbuckets = size;
 789                        for (i = 0; i < size; i++) {
 790                                INIT_LIST_HEAD(&buckets[i].written);
 791                                INIT_LIST_HEAD(&buckets[i].committing);
 792                                /* mark direct verifier as unset */
 793                                buckets[i].direct_verf.committed =
 794                                        NFS_INVALID_STABLE_HOW;
 795                        }
 796                }
 797                spin_unlock(&cinfo->inode->i_lock);
 798                return 0;
 799        }
 800}
 801
 802static struct nfs4_pnfs_ds *
 803ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 804                                  int start_idx,
 805                                  int *best_idx)
 806{
 807        struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 808        struct nfs4_pnfs_ds *ds;
 809        bool fail_return = false;
 810        int idx;
 811
 812        /* mirrors are sorted by efficiency */
 813        for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 814                if (idx+1 == fls->mirror_array_cnt)
 815                        fail_return = true;
 816                ds = nfs4_ff_layout_prepare_ds(lseg, idx, fail_return);
 817                if (ds) {
 818                        *best_idx = idx;
 819                        return ds;
 820                }
 821        }
 822
 823        return NULL;
 824}
 825
 826static void
 827ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 828                      struct nfs_page *req,
 829                      bool strict_iomode)
 830{
 831retry_strict:
 832        pnfs_put_lseg(pgio->pg_lseg);
 833        pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 834                                           req->wb_context,
 835                                           0,
 836                                           NFS4_MAX_UINT64,
 837                                           IOMODE_READ,
 838                                           strict_iomode,
 839                                           GFP_KERNEL);
 840        if (IS_ERR(pgio->pg_lseg)) {
 841                pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 842                pgio->pg_lseg = NULL;
 843        }
 844
 845        /* If we don't have checking, do get a IOMODE_RW
 846         * segment, and the server wants to avoid READs
 847         * there, then retry!
 848         */
 849        if (pgio->pg_lseg && !strict_iomode &&
 850            ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 851                strict_iomode = true;
 852                goto retry_strict;
 853        }
 854}
 855
 856static void
 857ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 858                        struct nfs_page *req)
 859{
 860        struct nfs_pgio_mirror *pgm;
 861        struct nfs4_ff_layout_mirror *mirror;
 862        struct nfs4_pnfs_ds *ds;
 863        int ds_idx;
 864
 865retry:
 866        /* Use full layout for now */
 867        if (!pgio->pg_lseg)
 868                ff_layout_pg_get_read(pgio, req, false);
 869        else if (ff_layout_avoid_read_on_rw(pgio->pg_lseg))
 870                ff_layout_pg_get_read(pgio, req, true);
 871
 872        /* If no lseg, fall back to read through mds */
 873        if (pgio->pg_lseg == NULL)
 874                goto out_mds;
 875
 876        ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 877        if (!ds) {
 878                if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 879                        goto out_mds;
 880                pnfs_put_lseg(pgio->pg_lseg);
 881                pgio->pg_lseg = NULL;
 882                /* Sleep for 1 second before retrying */
 883                ssleep(1);
 884                goto retry;
 885        }
 886
 887        mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 888
 889        pgio->pg_mirror_idx = ds_idx;
 890
 891        /* read always uses only one mirror - idx 0 for pgio layer */
 892        pgm = &pgio->pg_mirrors[0];
 893        pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 894
 895        return;
 896out_mds:
 897        pnfs_put_lseg(pgio->pg_lseg);
 898        pgio->pg_lseg = NULL;
 899        nfs_pageio_reset_read_mds(pgio);
 900}
 901
 902static void
 903ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 904                        struct nfs_page *req)
 905{
 906        struct nfs4_ff_layout_mirror *mirror;
 907        struct nfs_pgio_mirror *pgm;
 908        struct nfs_commit_info cinfo;
 909        struct nfs4_pnfs_ds *ds;
 910        int i;
 911        int status;
 912
 913retry:
 914        if (!pgio->pg_lseg) {
 915                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 916                                                   req->wb_context,
 917                                                   0,
 918                                                   NFS4_MAX_UINT64,
 919                                                   IOMODE_RW,
 920                                                   false,
 921                                                   GFP_NOFS);
 922                if (IS_ERR(pgio->pg_lseg)) {
 923                        pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 924                        pgio->pg_lseg = NULL;
 925                        return;
 926                }
 927        }
 928        /* If no lseg, fall back to write through mds */
 929        if (pgio->pg_lseg == NULL)
 930                goto out_mds;
 931
 932        nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 933        status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 934        if (status < 0)
 935                goto out_mds;
 936
 937        /* Use a direct mapping of ds_idx to pgio mirror_idx */
 938        if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 939            FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 940                goto out_mds;
 941
 942        for (i = 0; i < pgio->pg_mirror_count; i++) {
 943                ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 944                if (!ds) {
 945                        if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 946                                goto out_mds;
 947                        pnfs_put_lseg(pgio->pg_lseg);
 948                        pgio->pg_lseg = NULL;
 949                        /* Sleep for 1 second before retrying */
 950                        ssleep(1);
 951                        goto retry;
 952                }
 953                pgm = &pgio->pg_mirrors[i];
 954                mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 955                pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 956        }
 957
 958        return;
 959
 960out_mds:
 961        pnfs_put_lseg(pgio->pg_lseg);
 962        pgio->pg_lseg = NULL;
 963        nfs_pageio_reset_write_mds(pgio);
 964}
 965
 966static unsigned int
 967ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 968                                    struct nfs_page *req)
 969{
 970        if (!pgio->pg_lseg) {
 971                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 972                                                   req->wb_context,
 973                                                   0,
 974                                                   NFS4_MAX_UINT64,
 975                                                   IOMODE_RW,
 976                                                   false,
 977                                                   GFP_NOFS);
 978                if (IS_ERR(pgio->pg_lseg)) {
 979                        pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 980                        pgio->pg_lseg = NULL;
 981                        goto out;
 982                }
 983        }
 984        if (pgio->pg_lseg)
 985                return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 986
 987        /* no lseg means that pnfs is not in use, so no mirroring here */
 988        nfs_pageio_reset_write_mds(pgio);
 989out:
 990        return 1;
 991}
 992
 993static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 994        .pg_init = ff_layout_pg_init_read,
 995        .pg_test = pnfs_generic_pg_test,
 996        .pg_doio = pnfs_generic_pg_readpages,
 997        .pg_cleanup = pnfs_generic_pg_cleanup,
 998};
 999
1000static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1001        .pg_init = ff_layout_pg_init_write,
1002        .pg_test = pnfs_generic_pg_test,
1003        .pg_doio = pnfs_generic_pg_writepages,
1004        .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1005        .pg_cleanup = pnfs_generic_pg_cleanup,
1006};
1007
1008static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1009{
1010        struct rpc_task *task = &hdr->task;
1011
1012        pnfs_layoutcommit_inode(hdr->inode, false);
1013
1014        if (retry_pnfs) {
1015                dprintk("%s Reset task %5u for i/o through pNFS "
1016                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1017                        hdr->task.tk_pid,
1018                        hdr->inode->i_sb->s_id,
1019                        (unsigned long long)NFS_FILEID(hdr->inode),
1020                        hdr->args.count,
1021                        (unsigned long long)hdr->args.offset);
1022
1023                hdr->completion_ops->reschedule_io(hdr);
1024                return;
1025        }
1026
1027        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1028                dprintk("%s Reset task %5u for i/o through MDS "
1029                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1030                        hdr->task.tk_pid,
1031                        hdr->inode->i_sb->s_id,
1032                        (unsigned long long)NFS_FILEID(hdr->inode),
1033                        hdr->args.count,
1034                        (unsigned long long)hdr->args.offset);
1035
1036                task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1037        }
1038}
1039
1040static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1041{
1042        struct rpc_task *task = &hdr->task;
1043
1044        pnfs_layoutcommit_inode(hdr->inode, false);
1045
1046        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1047                dprintk("%s Reset task %5u for i/o through MDS "
1048                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1049                        hdr->task.tk_pid,
1050                        hdr->inode->i_sb->s_id,
1051                        (unsigned long long)NFS_FILEID(hdr->inode),
1052                        hdr->args.count,
1053                        (unsigned long long)hdr->args.offset);
1054
1055                task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1056        }
1057}
1058
1059static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1060                                           struct nfs4_state *state,
1061                                           struct nfs_client *clp,
1062                                           struct pnfs_layout_segment *lseg,
1063                                           int idx)
1064{
1065        struct pnfs_layout_hdr *lo = lseg->pls_layout;
1066        struct inode *inode = lo->plh_inode;
1067        struct nfs_server *mds_server = NFS_SERVER(inode);
1068
1069        struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1070        struct nfs_client *mds_client = mds_server->nfs_client;
1071        struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1072
1073        if (task->tk_status >= 0)
1074                return 0;
1075
1076        switch (task->tk_status) {
1077        /* MDS state errors */
1078        case -NFS4ERR_DELEG_REVOKED:
1079        case -NFS4ERR_ADMIN_REVOKED:
1080        case -NFS4ERR_BAD_STATEID:
1081                if (state == NULL)
1082                        break;
1083                nfs_remove_bad_delegation(state->inode);
1084        case -NFS4ERR_OPENMODE:
1085                if (state == NULL)
1086                        break;
1087                if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
1088                        goto out_bad_stateid;
1089                goto wait_on_recovery;
1090        case -NFS4ERR_EXPIRED:
1091                if (state != NULL) {
1092                        if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
1093                                goto out_bad_stateid;
1094                }
1095                nfs4_schedule_lease_recovery(mds_client);
1096                goto wait_on_recovery;
1097        /* DS session errors */
1098        case -NFS4ERR_BADSESSION:
1099        case -NFS4ERR_BADSLOT:
1100        case -NFS4ERR_BAD_HIGH_SLOT:
1101        case -NFS4ERR_DEADSESSION:
1102        case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1103        case -NFS4ERR_SEQ_FALSE_RETRY:
1104        case -NFS4ERR_SEQ_MISORDERED:
1105                dprintk("%s ERROR %d, Reset session. Exchangeid "
1106                        "flags 0x%x\n", __func__, task->tk_status,
1107                        clp->cl_exchange_flags);
1108                nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1109                break;
1110        case -NFS4ERR_DELAY:
1111        case -NFS4ERR_GRACE:
1112                rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1113                break;
1114        case -NFS4ERR_RETRY_UNCACHED_REP:
1115                break;
1116        /* Invalidate Layout errors */
1117        case -NFS4ERR_PNFS_NO_LAYOUT:
1118        case -ESTALE:           /* mapped NFS4ERR_STALE */
1119        case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1120        case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1121        case -NFS4ERR_FHEXPIRED:
1122        case -NFS4ERR_WRONG_TYPE:
1123                dprintk("%s Invalid layout error %d\n", __func__,
1124                        task->tk_status);
1125                /*
1126                 * Destroy layout so new i/o will get a new layout.
1127                 * Layout will not be destroyed until all current lseg
1128                 * references are put. Mark layout as invalid to resend failed
1129                 * i/o and all i/o waiting on the slot table to the MDS until
1130                 * layout is destroyed and a new valid layout is obtained.
1131                 */
1132                pnfs_destroy_layout(NFS_I(inode));
1133                rpc_wake_up(&tbl->slot_tbl_waitq);
1134                goto reset;
1135        /* RPC connection errors */
1136        case -ECONNREFUSED:
1137        case -EHOSTDOWN:
1138        case -EHOSTUNREACH:
1139        case -ENETUNREACH:
1140        case -EIO:
1141        case -ETIMEDOUT:
1142        case -EPIPE:
1143                dprintk("%s DS connection error %d\n", __func__,
1144                        task->tk_status);
1145                nfs4_mark_deviceid_unavailable(devid);
1146                rpc_wake_up(&tbl->slot_tbl_waitq);
1147                /* fall through */
1148        default:
1149                if (ff_layout_avoid_mds_available_ds(lseg))
1150                        return -NFS4ERR_RESET_TO_PNFS;
1151reset:
1152                dprintk("%s Retry through MDS. Error %d\n", __func__,
1153                        task->tk_status);
1154                return -NFS4ERR_RESET_TO_MDS;
1155        }
1156out:
1157        task->tk_status = 0;
1158        return -EAGAIN;
1159out_bad_stateid:
1160        task->tk_status = -EIO;
1161        return 0;
1162wait_on_recovery:
1163        rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
1164        if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
1165                rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
1166        goto out;
1167}
1168
1169/* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1170static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1171                                           struct pnfs_layout_segment *lseg,
1172                                           int idx)
1173{
1174        struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1175
1176        if (task->tk_status >= 0)
1177                return 0;
1178
1179        switch (task->tk_status) {
1180        /* File access problems. Don't mark the device as unavailable */
1181        case -EACCES:
1182        case -ESTALE:
1183        case -EISDIR:
1184        case -EBADHANDLE:
1185        case -ELOOP:
1186        case -ENOSPC:
1187                break;
1188        case -EJUKEBOX:
1189                nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1190                goto out_retry;
1191        default:
1192                dprintk("%s DS connection error %d\n", __func__,
1193                        task->tk_status);
1194                nfs4_mark_deviceid_unavailable(devid);
1195        }
1196        /* FIXME: Need to prevent infinite looping here. */
1197        return -NFS4ERR_RESET_TO_PNFS;
1198out_retry:
1199        task->tk_status = 0;
1200        rpc_restart_call_prepare(task);
1201        rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1202        return -EAGAIN;
1203}
1204
1205static int ff_layout_async_handle_error(struct rpc_task *task,
1206                                        struct nfs4_state *state,
1207                                        struct nfs_client *clp,
1208                                        struct pnfs_layout_segment *lseg,
1209                                        int idx)
1210{
1211        int vers = clp->cl_nfs_mod->rpc_vers->number;
1212
1213        switch (vers) {
1214        case 3:
1215                return ff_layout_async_handle_error_v3(task, lseg, idx);
1216        case 4:
1217                return ff_layout_async_handle_error_v4(task, state, clp,
1218                                                       lseg, idx);
1219        default:
1220                /* should never happen */
1221                WARN_ON_ONCE(1);
1222                return 0;
1223        }
1224}
1225
1226static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1227                                        int idx, u64 offset, u64 length,
1228                                        u32 status, int opnum, int error)
1229{
1230        struct nfs4_ff_layout_mirror *mirror;
1231        int err;
1232
1233        if (status == 0) {
1234                switch (error) {
1235                case -ETIMEDOUT:
1236                case -EPFNOSUPPORT:
1237                case -EPROTONOSUPPORT:
1238                case -EOPNOTSUPP:
1239                case -ECONNREFUSED:
1240                case -ECONNRESET:
1241                case -EHOSTDOWN:
1242                case -EHOSTUNREACH:
1243                case -ENETUNREACH:
1244                case -EADDRINUSE:
1245                case -ENOBUFS:
1246                case -EPIPE:
1247                case -EPERM:
1248                        status = NFS4ERR_NXIO;
1249                        break;
1250                case -EACCES:
1251                        status = NFS4ERR_ACCESS;
1252                        break;
1253                default:
1254                        return;
1255                }
1256        }
1257
1258        switch (status) {
1259        case NFS4ERR_DELAY:
1260        case NFS4ERR_GRACE:
1261                return;
1262        default:
1263                break;
1264        }
1265
1266        mirror = FF_LAYOUT_COMP(lseg, idx);
1267        err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1268                                       mirror, offset, length, status, opnum,
1269                                       GFP_NOIO);
1270        pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1271        dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1272}
1273
1274/* NFS_PROTO call done callback routines */
1275static int ff_layout_read_done_cb(struct rpc_task *task,
1276                                struct nfs_pgio_header *hdr)
1277{
1278        int err;
1279
1280        trace_nfs4_pnfs_read(hdr, task->tk_status);
1281        if (task->tk_status < 0)
1282                ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1283                                            hdr->args.offset, hdr->args.count,
1284                                            hdr->res.op_status, OP_READ,
1285                                            task->tk_status);
1286        err = ff_layout_async_handle_error(task, hdr->args.context->state,
1287                                           hdr->ds_clp, hdr->lseg,
1288                                           hdr->pgio_mirror_idx);
1289
1290        switch (err) {
1291        case -NFS4ERR_RESET_TO_PNFS:
1292                if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1293                                        hdr->pgio_mirror_idx + 1,
1294                                        &hdr->pgio_mirror_idx))
1295                        goto out_eagain;
1296                pnfs_read_resend_pnfs(hdr);
1297                return task->tk_status;
1298        case -NFS4ERR_RESET_TO_MDS:
1299                ff_layout_reset_read(hdr);
1300                return task->tk_status;
1301        case -EAGAIN:
1302                goto out_eagain;
1303        }
1304
1305        return 0;
1306out_eagain:
1307        rpc_restart_call_prepare(task);
1308        return -EAGAIN;
1309}
1310
1311static bool
1312ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1313{
1314        return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1315}
1316
1317/*
1318 * We reference the rpc_cred of the first WRITE that triggers the need for
1319 * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1320 * rfc5661 is not clear about which credential should be used.
1321 *
1322 * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1323 * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1324 * we always send layoutcommit after DS writes.
1325 */
1326static void
1327ff_layout_set_layoutcommit(struct inode *inode,
1328                struct pnfs_layout_segment *lseg,
1329                loff_t end_offset)
1330{
1331        if (!ff_layout_need_layoutcommit(lseg))
1332                return;
1333
1334        pnfs_set_layoutcommit(inode, lseg, end_offset);
1335        dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1336                (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1337}
1338
1339static bool
1340ff_layout_device_unavailable(struct pnfs_layout_segment *lseg, int idx)
1341{
1342        /* No mirroring for now */
1343        struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
1344
1345        return ff_layout_test_devid_unavailable(node);
1346}
1347
1348static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1349                struct nfs_pgio_header *hdr)
1350{
1351        if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1352                return;
1353        nfs4_ff_layout_stat_io_start_read(hdr->inode,
1354                        FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1355                        hdr->args.count,
1356                        task->tk_start);
1357}
1358
1359static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1360                struct nfs_pgio_header *hdr)
1361{
1362        if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1363                return;
1364        nfs4_ff_layout_stat_io_end_read(task,
1365                        FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1366                        hdr->args.count,
1367                        hdr->res.count);
1368}
1369
1370static int ff_layout_read_prepare_common(struct rpc_task *task,
1371                                         struct nfs_pgio_header *hdr)
1372{
1373        if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1374                rpc_exit(task, -EIO);
1375                return -EIO;
1376        }
1377        if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1378                rpc_exit(task, -EHOSTDOWN);
1379                return -EAGAIN;
1380        }
1381
1382        ff_layout_read_record_layoutstats_start(task, hdr);
1383        return 0;
1384}
1385
1386/*
1387 * Call ops for the async read/write cases
1388 * In the case of dense layouts, the offset needs to be reset to its
1389 * original value.
1390 */
1391static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1392{
1393        struct nfs_pgio_header *hdr = data;
1394
1395        if (ff_layout_read_prepare_common(task, hdr))
1396                return;
1397
1398        rpc_call_start(task);
1399}
1400
1401static int ff_layout_setup_sequence(struct nfs_client *ds_clp,
1402                                    struct nfs4_sequence_args *args,
1403                                    struct nfs4_sequence_res *res,
1404                                    struct rpc_task *task)
1405{
1406        if (ds_clp->cl_session)
1407                return nfs41_setup_sequence(ds_clp->cl_session,
1408                                           args,
1409                                           res,
1410                                           task);
1411        return nfs40_setup_sequence(ds_clp->cl_slot_tbl,
1412                                   args,
1413                                   res,
1414                                   task);
1415}
1416
1417static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1418{
1419        struct nfs_pgio_header *hdr = data;
1420
1421        if (ff_layout_setup_sequence(hdr->ds_clp,
1422                                     &hdr->args.seq_args,
1423                                     &hdr->res.seq_res,
1424                                     task))
1425                return;
1426
1427        if (ff_layout_read_prepare_common(task, hdr))
1428                return;
1429
1430        if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1431                        hdr->args.lock_context, FMODE_READ) == -EIO)
1432                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1433}
1434
1435static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1436{
1437        struct nfs_pgio_header *hdr = data;
1438
1439        dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1440
1441        if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1442            task->tk_status == 0) {
1443                nfs4_sequence_done(task, &hdr->res.seq_res);
1444                return;
1445        }
1446
1447        /* Note this may cause RPC to be resent */
1448        hdr->mds_ops->rpc_call_done(task, hdr);
1449}
1450
1451static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1452{
1453        struct nfs_pgio_header *hdr = data;
1454
1455        ff_layout_read_record_layoutstats_done(task, hdr);
1456        rpc_count_iostats_metrics(task,
1457            &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1458}
1459
1460static void ff_layout_read_release(void *data)
1461{
1462        struct nfs_pgio_header *hdr = data;
1463
1464        ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1465        pnfs_generic_rw_release(data);
1466}
1467
1468
1469static int ff_layout_write_done_cb(struct rpc_task *task,
1470                                struct nfs_pgio_header *hdr)
1471{
1472        loff_t end_offs = 0;
1473        int err;
1474
1475        trace_nfs4_pnfs_write(hdr, task->tk_status);
1476        if (task->tk_status < 0)
1477                ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1478                                            hdr->args.offset, hdr->args.count,
1479                                            hdr->res.op_status, OP_WRITE,
1480                                            task->tk_status);
1481        err = ff_layout_async_handle_error(task, hdr->args.context->state,
1482                                           hdr->ds_clp, hdr->lseg,
1483                                           hdr->pgio_mirror_idx);
1484
1485        switch (err) {
1486        case -NFS4ERR_RESET_TO_PNFS:
1487                ff_layout_reset_write(hdr, true);
1488                return task->tk_status;
1489        case -NFS4ERR_RESET_TO_MDS:
1490                ff_layout_reset_write(hdr, false);
1491                return task->tk_status;
1492        case -EAGAIN:
1493                return -EAGAIN;
1494        }
1495
1496        if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1497            hdr->res.verf->committed == NFS_DATA_SYNC)
1498                end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1499
1500        /* Note: if the write is unstable, don't set end_offs until commit */
1501        ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1502
1503        /* zero out fattr since we don't care DS attr at all */
1504        hdr->fattr.valid = 0;
1505        if (task->tk_status >= 0)
1506                nfs_writeback_update_inode(hdr);
1507
1508        return 0;
1509}
1510
1511static int ff_layout_commit_done_cb(struct rpc_task *task,
1512                                     struct nfs_commit_data *data)
1513{
1514        int err;
1515
1516        trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1517        if (task->tk_status < 0)
1518                ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1519                                            data->args.offset, data->args.count,
1520                                            data->res.op_status, OP_COMMIT,
1521                                            task->tk_status);
1522        err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1523                                           data->lseg, data->ds_commit_index);
1524
1525        switch (err) {
1526        case -NFS4ERR_RESET_TO_PNFS:
1527                pnfs_generic_prepare_to_resend_writes(data);
1528                return -EAGAIN;
1529        case -NFS4ERR_RESET_TO_MDS:
1530                pnfs_generic_prepare_to_resend_writes(data);
1531                return -EAGAIN;
1532        case -EAGAIN:
1533                rpc_restart_call_prepare(task);
1534                return -EAGAIN;
1535        }
1536
1537        ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1538
1539        return 0;
1540}
1541
1542static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1543                struct nfs_pgio_header *hdr)
1544{
1545        if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1546                return;
1547        nfs4_ff_layout_stat_io_start_write(hdr->inode,
1548                        FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1549                        hdr->args.count,
1550                        task->tk_start);
1551}
1552
1553static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1554                struct nfs_pgio_header *hdr)
1555{
1556        if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1557                return;
1558        nfs4_ff_layout_stat_io_end_write(task,
1559                        FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1560                        hdr->args.count, hdr->res.count,
1561                        hdr->res.verf->committed);
1562}
1563
1564static int ff_layout_write_prepare_common(struct rpc_task *task,
1565                                          struct nfs_pgio_header *hdr)
1566{
1567        if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1568                rpc_exit(task, -EIO);
1569                return -EIO;
1570        }
1571
1572        if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1573                rpc_exit(task, -EHOSTDOWN);
1574                return -EAGAIN;
1575        }
1576
1577        ff_layout_write_record_layoutstats_start(task, hdr);
1578        return 0;
1579}
1580
1581static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1582{
1583        struct nfs_pgio_header *hdr = data;
1584
1585        if (ff_layout_write_prepare_common(task, hdr))
1586                return;
1587
1588        rpc_call_start(task);
1589}
1590
1591static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1592{
1593        struct nfs_pgio_header *hdr = data;
1594
1595        if (ff_layout_setup_sequence(hdr->ds_clp,
1596                                     &hdr->args.seq_args,
1597                                     &hdr->res.seq_res,
1598                                     task))
1599                return;
1600
1601        if (ff_layout_write_prepare_common(task, hdr))
1602                return;
1603
1604        if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1605                        hdr->args.lock_context, FMODE_WRITE) == -EIO)
1606                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1607}
1608
1609static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1610{
1611        struct nfs_pgio_header *hdr = data;
1612
1613        if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1614            task->tk_status == 0) {
1615                nfs4_sequence_done(task, &hdr->res.seq_res);
1616                return;
1617        }
1618
1619        /* Note this may cause RPC to be resent */
1620        hdr->mds_ops->rpc_call_done(task, hdr);
1621}
1622
1623static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1624{
1625        struct nfs_pgio_header *hdr = data;
1626
1627        ff_layout_write_record_layoutstats_done(task, hdr);
1628        rpc_count_iostats_metrics(task,
1629            &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1630}
1631
1632static void ff_layout_write_release(void *data)
1633{
1634        struct nfs_pgio_header *hdr = data;
1635
1636        ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1637        pnfs_generic_rw_release(data);
1638}
1639
1640static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1641                struct nfs_commit_data *cdata)
1642{
1643        if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1644                return;
1645        nfs4_ff_layout_stat_io_start_write(cdata->inode,
1646                        FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1647                        0, task->tk_start);
1648}
1649
1650static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1651                struct nfs_commit_data *cdata)
1652{
1653        struct nfs_page *req;
1654        __u64 count = 0;
1655
1656        if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1657                return;
1658
1659        if (task->tk_status == 0) {
1660                list_for_each_entry(req, &cdata->pages, wb_list)
1661                        count += req->wb_bytes;
1662        }
1663        nfs4_ff_layout_stat_io_end_write(task,
1664                        FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1665                        count, count, NFS_FILE_SYNC);
1666}
1667
1668static void ff_layout_commit_prepare_common(struct rpc_task *task,
1669                struct nfs_commit_data *cdata)
1670{
1671        ff_layout_commit_record_layoutstats_start(task, cdata);
1672}
1673
1674static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1675{
1676        ff_layout_commit_prepare_common(task, data);
1677        rpc_call_start(task);
1678}
1679
1680static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1681{
1682        struct nfs_commit_data *wdata = data;
1683
1684        if (ff_layout_setup_sequence(wdata->ds_clp,
1685                                 &wdata->args.seq_args,
1686                                 &wdata->res.seq_res,
1687                                 task))
1688                return;
1689        ff_layout_commit_prepare_common(task, data);
1690}
1691
1692static void ff_layout_commit_done(struct rpc_task *task, void *data)
1693{
1694        pnfs_generic_write_commit_done(task, data);
1695}
1696
1697static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1698{
1699        struct nfs_commit_data *cdata = data;
1700
1701        ff_layout_commit_record_layoutstats_done(task, cdata);
1702        rpc_count_iostats_metrics(task,
1703            &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1704}
1705
1706static void ff_layout_commit_release(void *data)
1707{
1708        struct nfs_commit_data *cdata = data;
1709
1710        ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1711        pnfs_generic_commit_release(data);
1712}
1713
1714static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1715        .rpc_call_prepare = ff_layout_read_prepare_v3,
1716        .rpc_call_done = ff_layout_read_call_done,
1717        .rpc_count_stats = ff_layout_read_count_stats,
1718        .rpc_release = ff_layout_read_release,
1719};
1720
1721static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1722        .rpc_call_prepare = ff_layout_read_prepare_v4,
1723        .rpc_call_done = ff_layout_read_call_done,
1724        .rpc_count_stats = ff_layout_read_count_stats,
1725        .rpc_release = ff_layout_read_release,
1726};
1727
1728static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1729        .rpc_call_prepare = ff_layout_write_prepare_v3,
1730        .rpc_call_done = ff_layout_write_call_done,
1731        .rpc_count_stats = ff_layout_write_count_stats,
1732        .rpc_release = ff_layout_write_release,
1733};
1734
1735static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1736        .rpc_call_prepare = ff_layout_write_prepare_v4,
1737        .rpc_call_done = ff_layout_write_call_done,
1738        .rpc_count_stats = ff_layout_write_count_stats,
1739        .rpc_release = ff_layout_write_release,
1740};
1741
1742static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1743        .rpc_call_prepare = ff_layout_commit_prepare_v3,
1744        .rpc_call_done = ff_layout_commit_done,
1745        .rpc_count_stats = ff_layout_commit_count_stats,
1746        .rpc_release = ff_layout_commit_release,
1747};
1748
1749static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1750        .rpc_call_prepare = ff_layout_commit_prepare_v4,
1751        .rpc_call_done = ff_layout_commit_done,
1752        .rpc_count_stats = ff_layout_commit_count_stats,
1753        .rpc_release = ff_layout_commit_release,
1754};
1755
1756static enum pnfs_try_status
1757ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1758{
1759        struct pnfs_layout_segment *lseg = hdr->lseg;
1760        struct nfs4_pnfs_ds *ds;
1761        struct rpc_clnt *ds_clnt;
1762        struct rpc_cred *ds_cred;
1763        loff_t offset = hdr->args.offset;
1764        u32 idx = hdr->pgio_mirror_idx;
1765        int vers;
1766        struct nfs_fh *fh;
1767
1768        dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
1769                __func__, hdr->inode->i_ino,
1770                hdr->args.pgbase, (size_t)hdr->args.count, offset);
1771
1772        ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
1773        if (!ds)
1774                goto out_failed;
1775
1776        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1777                                                   hdr->inode);
1778        if (IS_ERR(ds_clnt))
1779                goto out_failed;
1780
1781        ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1782        if (!ds_cred)
1783                goto out_failed;
1784
1785        vers = nfs4_ff_layout_ds_version(lseg, idx);
1786
1787        dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1788                ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count), vers);
1789
1790        hdr->pgio_done_cb = ff_layout_read_done_cb;
1791        atomic_inc(&ds->ds_clp->cl_count);
1792        hdr->ds_clp = ds->ds_clp;
1793        fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1794        if (fh)
1795                hdr->args.fh = fh;
1796        /*
1797         * Note that if we ever decide to split across DSes,
1798         * then we may need to handle dense-like offsets.
1799         */
1800        hdr->args.offset = offset;
1801        hdr->mds_offset = offset;
1802
1803        /* Perform an asynchronous read to ds */
1804        nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1805                          vers == 3 ? &ff_layout_read_call_ops_v3 :
1806                                      &ff_layout_read_call_ops_v4,
1807                          0, RPC_TASK_SOFTCONN);
1808        put_rpccred(ds_cred);
1809        return PNFS_ATTEMPTED;
1810
1811out_failed:
1812        if (ff_layout_avoid_mds_available_ds(lseg))
1813                return PNFS_TRY_AGAIN;
1814        return PNFS_NOT_ATTEMPTED;
1815}
1816
1817/* Perform async writes. */
1818static enum pnfs_try_status
1819ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1820{
1821        struct pnfs_layout_segment *lseg = hdr->lseg;
1822        struct nfs4_pnfs_ds *ds;
1823        struct rpc_clnt *ds_clnt;
1824        struct rpc_cred *ds_cred;
1825        loff_t offset = hdr->args.offset;
1826        int vers;
1827        struct nfs_fh *fh;
1828        int idx = hdr->pgio_mirror_idx;
1829
1830        ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1831        if (!ds)
1832                return PNFS_NOT_ATTEMPTED;
1833
1834        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1835                                                   hdr->inode);
1836        if (IS_ERR(ds_clnt))
1837                return PNFS_NOT_ATTEMPTED;
1838
1839        ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1840        if (!ds_cred)
1841                return PNFS_NOT_ATTEMPTED;
1842
1843        vers = nfs4_ff_layout_ds_version(lseg, idx);
1844
1845        dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d vers %d\n",
1846                __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1847                offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count),
1848                vers);
1849
1850        hdr->pgio_done_cb = ff_layout_write_done_cb;
1851        atomic_inc(&ds->ds_clp->cl_count);
1852        hdr->ds_clp = ds->ds_clp;
1853        hdr->ds_commit_idx = idx;
1854        fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1855        if (fh)
1856                hdr->args.fh = fh;
1857
1858        /*
1859         * Note that if we ever decide to split across DSes,
1860         * then we may need to handle dense-like offsets.
1861         */
1862        hdr->args.offset = offset;
1863
1864        /* Perform an asynchronous write */
1865        nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1866                          vers == 3 ? &ff_layout_write_call_ops_v3 :
1867                                      &ff_layout_write_call_ops_v4,
1868                          sync, RPC_TASK_SOFTCONN);
1869        put_rpccred(ds_cred);
1870        return PNFS_ATTEMPTED;
1871}
1872
1873static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1874{
1875        return i;
1876}
1877
1878static struct nfs_fh *
1879select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1880{
1881        struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1882
1883        /* FIXME: Assume that there is only one NFS version available
1884         * for the DS.
1885         */
1886        return &flseg->mirror_array[i]->fh_versions[0];
1887}
1888
1889static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1890{
1891        struct pnfs_layout_segment *lseg = data->lseg;
1892        struct nfs4_pnfs_ds *ds;
1893        struct rpc_clnt *ds_clnt;
1894        struct rpc_cred *ds_cred;
1895        u32 idx;
1896        int vers, ret;
1897        struct nfs_fh *fh;
1898
1899        idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1900        ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1901        if (!ds)
1902                goto out_err;
1903
1904        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1905                                                   data->inode);
1906        if (IS_ERR(ds_clnt))
1907                goto out_err;
1908
1909        ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1910        if (!ds_cred)
1911                goto out_err;
1912
1913        vers = nfs4_ff_layout_ds_version(lseg, idx);
1914
1915        dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1916                data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count),
1917                vers);
1918        data->commit_done_cb = ff_layout_commit_done_cb;
1919        data->cred = ds_cred;
1920        atomic_inc(&ds->ds_clp->cl_count);
1921        data->ds_clp = ds->ds_clp;
1922        fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1923        if (fh)
1924                data->args.fh = fh;
1925
1926        ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1927                                   vers == 3 ? &ff_layout_commit_call_ops_v3 :
1928                                               &ff_layout_commit_call_ops_v4,
1929                                   how, RPC_TASK_SOFTCONN);
1930        put_rpccred(ds_cred);
1931        return ret;
1932out_err:
1933        pnfs_generic_prepare_to_resend_writes(data);
1934        pnfs_generic_commit_release(data);
1935        return -EAGAIN;
1936}
1937
1938static int
1939ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1940                           int how, struct nfs_commit_info *cinfo)
1941{
1942        return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1943                                            ff_layout_initiate_commit);
1944}
1945
1946static struct pnfs_ds_commit_info *
1947ff_layout_get_ds_info(struct inode *inode)
1948{
1949        struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1950
1951        if (layout == NULL)
1952                return NULL;
1953
1954        return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1955}
1956
1957static void
1958ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1959{
1960        nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1961                                                  id_node));
1962}
1963
1964static int ff_layout_encode_ioerr(struct nfs4_flexfile_layout *flo,
1965                                  struct xdr_stream *xdr,
1966                                  const struct nfs4_layoutreturn_args *args)
1967{
1968        struct pnfs_layout_hdr *hdr = &flo->generic_hdr;
1969        __be32 *start;
1970        int count = 0, ret = 0;
1971
1972        start = xdr_reserve_space(xdr, 4);
1973        if (unlikely(!start))
1974                return -E2BIG;
1975
1976        /* This assume we always return _ALL_ layouts */
1977        spin_lock(&hdr->plh_inode->i_lock);
1978        ret = ff_layout_encode_ds_ioerr(flo, xdr, &count, &args->range);
1979        spin_unlock(&hdr->plh_inode->i_lock);
1980
1981        *start = cpu_to_be32(count);
1982
1983        return ret;
1984}
1985
1986/* report nothing for now */
1987static void ff_layout_encode_iostats(struct nfs4_flexfile_layout *flo,
1988                                     struct xdr_stream *xdr,
1989                                     const struct nfs4_layoutreturn_args *args)
1990{
1991        __be32 *p;
1992
1993        p = xdr_reserve_space(xdr, 4);
1994        if (likely(p))
1995                *p = cpu_to_be32(0);
1996}
1997
1998static struct nfs4_deviceid_node *
1999ff_layout_alloc_deviceid_node(struct nfs_server *server,
2000                              struct pnfs_device *pdev, gfp_t gfp_flags)
2001{
2002        struct nfs4_ff_layout_ds *dsaddr;
2003
2004        dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2005        if (!dsaddr)
2006                return NULL;
2007        return &dsaddr->id_node;
2008}
2009
2010static void
2011ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
2012                              struct xdr_stream *xdr,
2013                              const struct nfs4_layoutreturn_args *args)
2014{
2015        struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo);
2016        __be32 *start;
2017
2018        dprintk("%s: Begin\n", __func__);
2019        start = xdr_reserve_space(xdr, 4);
2020        BUG_ON(!start);
2021
2022        ff_layout_encode_ioerr(flo, xdr, args);
2023        ff_layout_encode_iostats(flo, xdr, args);
2024
2025        *start = cpu_to_be32((xdr->p - start - 1) * 4);
2026        dprintk("%s: Return\n", __func__);
2027}
2028
2029static int
2030ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2031{
2032        const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2033
2034        return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2035}
2036
2037static size_t
2038ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2039                          const int buflen)
2040{
2041        const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2042        const struct in6_addr *addr = &sin6->sin6_addr;
2043
2044        /*
2045         * RFC 4291, Section 2.2.2
2046         *
2047         * Shorthanded ANY address
2048         */
2049        if (ipv6_addr_any(addr))
2050                return snprintf(buf, buflen, "::");
2051
2052        /*
2053         * RFC 4291, Section 2.2.2
2054         *
2055         * Shorthanded loopback address
2056         */
2057        if (ipv6_addr_loopback(addr))
2058                return snprintf(buf, buflen, "::1");
2059
2060        /*
2061         * RFC 4291, Section 2.2.3
2062         *
2063         * Special presentation address format for mapped v4
2064         * addresses.
2065         */
2066        if (ipv6_addr_v4mapped(addr))
2067                return snprintf(buf, buflen, "::ffff:%pI4",
2068                                        &addr->s6_addr32[3]);
2069
2070        /*
2071         * RFC 4291, Section 2.2.1
2072         */
2073        return snprintf(buf, buflen, "%pI6c", addr);
2074}
2075
2076/* Derived from rpc_sockaddr2uaddr */
2077static void
2078ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2079{
2080        struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2081        char portbuf[RPCBIND_MAXUADDRPLEN];
2082        char addrbuf[RPCBIND_MAXUADDRLEN];
2083        char *netid;
2084        unsigned short port;
2085        int len, netid_len;
2086        __be32 *p;
2087
2088        switch (sap->sa_family) {
2089        case AF_INET:
2090                if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2091                        return;
2092                port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2093                netid = "tcp";
2094                netid_len = 3;
2095                break;
2096        case AF_INET6:
2097                if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2098                        return;
2099                port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2100                netid = "tcp6";
2101                netid_len = 4;
2102                break;
2103        default:
2104                /* we only support tcp and tcp6 */
2105                WARN_ON_ONCE(1);
2106                return;
2107        }
2108
2109        snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2110        len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2111
2112        p = xdr_reserve_space(xdr, 4 + netid_len);
2113        xdr_encode_opaque(p, netid, netid_len);
2114
2115        p = xdr_reserve_space(xdr, 4 + len);
2116        xdr_encode_opaque(p, addrbuf, len);
2117}
2118
2119static void
2120ff_layout_encode_nfstime(struct xdr_stream *xdr,
2121                         ktime_t t)
2122{
2123        struct timespec64 ts;
2124        __be32 *p;
2125
2126        p = xdr_reserve_space(xdr, 12);
2127        ts = ktime_to_timespec64(t);
2128        p = xdr_encode_hyper(p, ts.tv_sec);
2129        *p++ = cpu_to_be32(ts.tv_nsec);
2130}
2131
2132static void
2133ff_layout_encode_io_latency(struct xdr_stream *xdr,
2134                            struct nfs4_ff_io_stat *stat)
2135{
2136        __be32 *p;
2137
2138        p = xdr_reserve_space(xdr, 5 * 8);
2139        p = xdr_encode_hyper(p, stat->ops_requested);
2140        p = xdr_encode_hyper(p, stat->bytes_requested);
2141        p = xdr_encode_hyper(p, stat->ops_completed);
2142        p = xdr_encode_hyper(p, stat->bytes_completed);
2143        p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2144        ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2145        ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2146}
2147
2148static void
2149ff_layout_encode_layoutstats(struct xdr_stream *xdr,
2150                             struct nfs42_layoutstat_args *args,
2151                             struct nfs42_layoutstat_devinfo *devinfo)
2152{
2153        struct nfs4_ff_layout_mirror *mirror = devinfo->layout_private;
2154        struct nfs4_pnfs_ds_addr *da;
2155        struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2156        struct nfs_fh *fh = &mirror->fh_versions[0];
2157        __be32 *p, *start;
2158
2159        da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2160        dprintk("%s: DS %s: encoding address %s\n",
2161                __func__, ds->ds_remotestr, da->da_remotestr);
2162        /* layoutupdate length */
2163        start = xdr_reserve_space(xdr, 4);
2164        /* netaddr4 */
2165        ff_layout_encode_netaddr(xdr, da);
2166        /* nfs_fh4 */
2167        p = xdr_reserve_space(xdr, 4 + fh->size);
2168        xdr_encode_opaque(p, fh->data, fh->size);
2169        /* ff_io_latency4 read */
2170        spin_lock(&mirror->lock);
2171        ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2172        /* ff_io_latency4 write */
2173        ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2174        spin_unlock(&mirror->lock);
2175        /* nfstime4 */
2176        ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2177        /* bool */
2178        p = xdr_reserve_space(xdr, 4);
2179        *p = cpu_to_be32(false);
2180
2181        *start = cpu_to_be32((xdr->p - start - 1) * 4);
2182}
2183
2184static int
2185ff_layout_mirror_prepare_stats(struct nfs42_layoutstat_args *args,
2186                               struct pnfs_layout_hdr *lo,
2187                               int dev_limit)
2188{
2189        struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2190        struct nfs4_ff_layout_mirror *mirror;
2191        struct nfs4_deviceid_node *dev;
2192        struct nfs42_layoutstat_devinfo *devinfo;
2193        int i = 0;
2194
2195        list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2196                if (i >= dev_limit)
2197                        break;
2198                if (!mirror->mirror_ds)
2199                        continue;
2200                /* mirror refcount put in cleanup_layoutstats */
2201                if (!atomic_inc_not_zero(&mirror->ref))
2202                        continue;
2203                dev = &mirror->mirror_ds->id_node; 
2204                devinfo = &args->devinfo[i];
2205                memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2206                devinfo->offset = 0;
2207                devinfo->length = NFS4_MAX_UINT64;
2208                devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2209                devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2210                devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2211                devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2212                devinfo->layout_type = LAYOUT_FLEX_FILES;
2213                devinfo->layoutstats_encode = ff_layout_encode_layoutstats;
2214                devinfo->layout_private = mirror;
2215
2216                i++;
2217        }
2218        return i;
2219}
2220
2221static int
2222ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2223{
2224        struct nfs4_flexfile_layout *ff_layout;
2225        struct nfs4_ff_layout_mirror *mirror;
2226        int dev_count = 0;
2227
2228        spin_lock(&args->inode->i_lock);
2229        ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2230        list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2231                if (atomic_read(&mirror->ref) != 0)
2232                        dev_count ++;
2233        }
2234        spin_unlock(&args->inode->i_lock);
2235        /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2236        if (dev_count > PNFS_LAYOUTSTATS_MAXDEV) {
2237                dprintk("%s: truncating devinfo to limit (%d:%d)\n",
2238                        __func__, dev_count, PNFS_LAYOUTSTATS_MAXDEV);
2239                dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2240        }
2241        args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2242        if (!args->devinfo)
2243                return -ENOMEM;
2244
2245        spin_lock(&args->inode->i_lock);
2246        args->num_dev = ff_layout_mirror_prepare_stats(args,
2247                        &ff_layout->generic_hdr, dev_count);
2248        spin_unlock(&args->inode->i_lock);
2249
2250        return 0;
2251}
2252
2253static void
2254ff_layout_cleanup_layoutstats(struct nfs42_layoutstat_data *data)
2255{
2256        struct nfs4_ff_layout_mirror *mirror;
2257        int i;
2258
2259        for (i = 0; i < data->args.num_dev; i++) {
2260                mirror = data->args.devinfo[i].layout_private;
2261                data->args.devinfo[i].layout_private = NULL;
2262                ff_layout_put_mirror(mirror);
2263        }
2264}
2265
2266static struct pnfs_layoutdriver_type flexfilelayout_type = {
2267        .id                     = LAYOUT_FLEX_FILES,
2268        .name                   = "LAYOUT_FLEX_FILES",
2269        .owner                  = THIS_MODULE,
2270        .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2271        .free_layout_hdr        = ff_layout_free_layout_hdr,
2272        .alloc_lseg             = ff_layout_alloc_lseg,
2273        .free_lseg              = ff_layout_free_lseg,
2274        .add_lseg               = ff_layout_add_lseg,
2275        .pg_read_ops            = &ff_layout_pg_read_ops,
2276        .pg_write_ops           = &ff_layout_pg_write_ops,
2277        .get_ds_info            = ff_layout_get_ds_info,
2278        .free_deviceid_node     = ff_layout_free_deviceid_node,
2279        .mark_request_commit    = pnfs_layout_mark_request_commit,
2280        .clear_request_commit   = pnfs_generic_clear_request_commit,
2281        .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2282        .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2283        .commit_pagelist        = ff_layout_commit_pagelist,
2284        .read_pagelist          = ff_layout_read_pagelist,
2285        .write_pagelist         = ff_layout_write_pagelist,
2286        .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2287        .encode_layoutreturn    = ff_layout_encode_layoutreturn,
2288        .sync                   = pnfs_nfs_generic_sync,
2289        .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2290        .cleanup_layoutstats    = ff_layout_cleanup_layoutstats,
2291};
2292
2293static int __init nfs4flexfilelayout_init(void)
2294{
2295        printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2296               __func__);
2297        if (!ff_zero_group) {
2298                ff_zero_group = groups_alloc(0);
2299                if (!ff_zero_group)
2300                        return -ENOMEM;
2301        }
2302        return pnfs_register_layoutdriver(&flexfilelayout_type);
2303}
2304
2305static void __exit nfs4flexfilelayout_exit(void)
2306{
2307        printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2308               __func__);
2309        pnfs_unregister_layoutdriver(&flexfilelayout_type);
2310        if (ff_zero_group) {
2311                put_group_info(ff_zero_group);
2312                ff_zero_group = NULL;
2313        }
2314}
2315
2316MODULE_ALIAS("nfs-layouttype4-4");
2317
2318MODULE_LICENSE("GPL");
2319MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2320
2321module_init(nfs4flexfilelayout_init);
2322module_exit(nfs4flexfilelayout_exit);
2323