linux/fs/afs/dir.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* dir.c: AFS filesystem directory handling
   3 *
   4 * Copyright (C) 2002, 2018 Red Hat, Inc. All Rights Reserved.
   5 * Written by David Howells (dhowells@redhat.com)
   6 */
   7
   8#include <linux/kernel.h>
   9#include <linux/fs.h>
  10#include <linux/namei.h>
  11#include <linux/pagemap.h>
  12#include <linux/swap.h>
  13#include <linux/ctype.h>
  14#include <linux/sched.h>
  15#include <linux/task_io_accounting_ops.h>
  16#include "internal.h"
  17#include "afs_fs.h"
  18#include "xdr_fs.h"
  19
  20static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
  21                                 unsigned int flags);
  22static int afs_dir_open(struct inode *inode, struct file *file);
  23static int afs_readdir(struct file *file, struct dir_context *ctx);
  24static int afs_d_revalidate(struct dentry *dentry, unsigned int flags);
  25static int afs_d_delete(const struct dentry *dentry);
  26static void afs_d_iput(struct dentry *dentry, struct inode *inode);
  27static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen,
  28                                  loff_t fpos, u64 ino, unsigned dtype);
  29static int afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen,
  30                              loff_t fpos, u64 ino, unsigned dtype);
  31static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
  32                      bool excl);
  33static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
  34static int afs_rmdir(struct inode *dir, struct dentry *dentry);
  35static int afs_unlink(struct inode *dir, struct dentry *dentry);
  36static int afs_link(struct dentry *from, struct inode *dir,
  37                    struct dentry *dentry);
  38static int afs_symlink(struct inode *dir, struct dentry *dentry,
  39                       const char *content);
  40static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
  41                      struct inode *new_dir, struct dentry *new_dentry,
  42                      unsigned int flags);
  43static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags);
  44static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
  45                                   unsigned int length);
  46
  47static int afs_dir_set_page_dirty(struct page *page)
  48{
  49        BUG(); /* This should never happen. */
  50}
  51
  52const struct file_operations afs_dir_file_operations = {
  53        .open           = afs_dir_open,
  54        .release        = afs_release,
  55        .iterate_shared = afs_readdir,
  56        .lock           = afs_lock,
  57        .llseek         = generic_file_llseek,
  58};
  59
  60const struct inode_operations afs_dir_inode_operations = {
  61        .create         = afs_create,
  62        .lookup         = afs_lookup,
  63        .link           = afs_link,
  64        .unlink         = afs_unlink,
  65        .symlink        = afs_symlink,
  66        .mkdir          = afs_mkdir,
  67        .rmdir          = afs_rmdir,
  68        .rename         = afs_rename,
  69        .permission     = afs_permission,
  70        .getattr        = afs_getattr,
  71        .setattr        = afs_setattr,
  72        .listxattr      = afs_listxattr,
  73};
  74
  75const struct address_space_operations afs_dir_aops = {
  76        .set_page_dirty = afs_dir_set_page_dirty,
  77        .releasepage    = afs_dir_releasepage,
  78        .invalidatepage = afs_dir_invalidatepage,
  79};
  80
  81const struct dentry_operations afs_fs_dentry_operations = {
  82        .d_revalidate   = afs_d_revalidate,
  83        .d_delete       = afs_d_delete,
  84        .d_release      = afs_d_release,
  85        .d_automount    = afs_d_automount,
  86        .d_iput         = afs_d_iput,
  87};
  88
  89struct afs_lookup_one_cookie {
  90        struct dir_context      ctx;
  91        struct qstr             name;
  92        bool                    found;
  93        struct afs_fid          fid;
  94};
  95
  96struct afs_lookup_cookie {
  97        struct dir_context      ctx;
  98        struct qstr             name;
  99        bool                    found;
 100        bool                    one_only;
 101        unsigned short          nr_fids;
 102        struct inode            **inodes;
 103        struct afs_status_cb    *statuses;
 104        struct afs_fid          fids[50];
 105};
 106
 107/*
 108 * check that a directory page is valid
 109 */
 110static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page,
 111                               loff_t i_size)
 112{
 113        struct afs_xdr_dir_page *dbuf;
 114        loff_t latter, off;
 115        int tmp, qty;
 116
 117        /* Determine how many magic numbers there should be in this page, but
 118         * we must take care because the directory may change size under us.
 119         */
 120        off = page_offset(page);
 121        if (i_size <= off)
 122                goto checked;
 123
 124        latter = i_size - off;
 125        if (latter >= PAGE_SIZE)
 126                qty = PAGE_SIZE;
 127        else
 128                qty = latter;
 129        qty /= sizeof(union afs_xdr_dir_block);
 130
 131        /* check them */
 132        dbuf = kmap(page);
 133        for (tmp = 0; tmp < qty; tmp++) {
 134                if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) {
 135                        printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n",
 136                               __func__, dvnode->vfs_inode.i_ino, tmp, qty,
 137                               ntohs(dbuf->blocks[tmp].hdr.magic));
 138                        trace_afs_dir_check_failed(dvnode, off, i_size);
 139                        kunmap(page);
 140                        trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
 141                        goto error;
 142                }
 143
 144                /* Make sure each block is NUL terminated so we can reasonably
 145                 * use string functions on it.  The filenames in the page
 146                 * *should* be NUL-terminated anyway.
 147                 */
 148                ((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0;
 149        }
 150
 151        kunmap(page);
 152
 153checked:
 154        afs_stat_v(dvnode, n_read_dir);
 155        return true;
 156
 157error:
 158        return false;
 159}
 160
 161/*
 162 * Check the contents of a directory that we've just read.
 163 */
 164static bool afs_dir_check_pages(struct afs_vnode *dvnode, struct afs_read *req)
 165{
 166        struct afs_xdr_dir_page *dbuf;
 167        unsigned int i, j, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block);
 168
 169        for (i = 0; i < req->nr_pages; i++)
 170                if (!afs_dir_check_page(dvnode, req->pages[i], req->actual_len))
 171                        goto bad;
 172        return true;
 173
 174bad:
 175        pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx r=%llx\n",
 176                dvnode->fid.vid, dvnode->fid.vnode,
 177                req->file_size, req->len, req->actual_len, req->remain);
 178        pr_warn("DIR %llx %x %x %x\n",
 179                req->pos, req->index, req->nr_pages, req->offset);
 180
 181        for (i = 0; i < req->nr_pages; i++) {
 182                dbuf = kmap(req->pages[i]);
 183                for (j = 0; j < qty; j++) {
 184                        union afs_xdr_dir_block *block = &dbuf->blocks[j];
 185
 186                        pr_warn("[%02x] %32phN\n", i * qty + j, block);
 187                }
 188                kunmap(req->pages[i]);
 189        }
 190        return false;
 191}
 192
 193/*
 194 * open an AFS directory file
 195 */
 196static int afs_dir_open(struct inode *inode, struct file *file)
 197{
 198        _enter("{%lu}", inode->i_ino);
 199
 200        BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 201        BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 202
 203        if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
 204                return -ENOENT;
 205
 206        return afs_open(inode, file);
 207}
 208
 209/*
 210 * Read the directory into the pagecache in one go, scrubbing the previous
 211 * contents.  The list of pages is returned, pinning them so that they don't
 212 * get reclaimed during the iteration.
 213 */
 214static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
 215        __acquires(&dvnode->validate_lock)
 216{
 217        struct afs_read *req;
 218        loff_t i_size;
 219        int nr_pages, nr_inline, i, n;
 220        int ret = -ENOMEM;
 221
 222retry:
 223        i_size = i_size_read(&dvnode->vfs_inode);
 224        if (i_size < 2048)
 225                return ERR_PTR(afs_bad(dvnode, afs_file_error_dir_small));
 226        if (i_size > 2048 * 1024) {
 227                trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
 228                return ERR_PTR(-EFBIG);
 229        }
 230
 231        _enter("%llu", i_size);
 232
 233        /* Get a request record to hold the page list.  We want to hold it
 234         * inline if we can, but we don't want to make an order 1 allocation.
 235         */
 236        nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE;
 237        nr_inline = nr_pages;
 238        if (nr_inline > (PAGE_SIZE - sizeof(*req)) / sizeof(struct page *))
 239                nr_inline = 0;
 240
 241        req = kzalloc(struct_size(req, array, nr_inline), GFP_KERNEL);
 242        if (!req)
 243                return ERR_PTR(-ENOMEM);
 244
 245        refcount_set(&req->usage, 1);
 246        req->nr_pages = nr_pages;
 247        req->actual_len = i_size; /* May change */
 248        req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
 249        req->data_version = dvnode->status.data_version; /* May change */
 250        if (nr_inline > 0) {
 251                req->pages = req->array;
 252        } else {
 253                req->pages = kcalloc(nr_pages, sizeof(struct page *),
 254                                     GFP_KERNEL);
 255                if (!req->pages)
 256                        goto error;
 257        }
 258
 259        /* Get a list of all the pages that hold or will hold the directory
 260         * content.  We need to fill in any gaps that we might find where the
 261         * memory reclaimer has been at work.  If there are any gaps, we will
 262         * need to reread the entire directory contents.
 263         */
 264        i = 0;
 265        do {
 266                n = find_get_pages_contig(dvnode->vfs_inode.i_mapping, i,
 267                                          req->nr_pages - i,
 268                                          req->pages + i);
 269                _debug("find %u at %u/%u", n, i, req->nr_pages);
 270                if (n == 0) {
 271                        gfp_t gfp = dvnode->vfs_inode.i_mapping->gfp_mask;
 272
 273                        if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
 274                                afs_stat_v(dvnode, n_inval);
 275
 276                        ret = -ENOMEM;
 277                        req->pages[i] = __page_cache_alloc(gfp);
 278                        if (!req->pages[i])
 279                                goto error;
 280                        ret = add_to_page_cache_lru(req->pages[i],
 281                                                    dvnode->vfs_inode.i_mapping,
 282                                                    i, gfp);
 283                        if (ret < 0)
 284                                goto error;
 285
 286                        set_page_private(req->pages[i], 1);
 287                        SetPagePrivate(req->pages[i]);
 288                        unlock_page(req->pages[i]);
 289                        i++;
 290                } else {
 291                        i += n;
 292                }
 293        } while (i < req->nr_pages);
 294
 295        /* If we're going to reload, we need to lock all the pages to prevent
 296         * races.
 297         */
 298        ret = -ERESTARTSYS;
 299        if (down_read_killable(&dvnode->validate_lock) < 0)
 300                goto error;
 301
 302        if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
 303                goto success;
 304
 305        up_read(&dvnode->validate_lock);
 306        if (down_write_killable(&dvnode->validate_lock) < 0)
 307                goto error;
 308
 309        if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
 310                trace_afs_reload_dir(dvnode);
 311                ret = afs_fetch_data(dvnode, key, req);
 312                if (ret < 0)
 313                        goto error_unlock;
 314
 315                task_io_account_read(PAGE_SIZE * req->nr_pages);
 316
 317                if (req->len < req->file_size)
 318                        goto content_has_grown;
 319
 320                /* Validate the data we just read. */
 321                ret = -EIO;
 322                if (!afs_dir_check_pages(dvnode, req))
 323                        goto error_unlock;
 324
 325                // TODO: Trim excess pages
 326
 327                set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags);
 328        }
 329
 330        downgrade_write(&dvnode->validate_lock);
 331success:
 332        return req;
 333
 334error_unlock:
 335        up_write(&dvnode->validate_lock);
 336error:
 337        afs_put_read(req);
 338        _leave(" = %d", ret);
 339        return ERR_PTR(ret);
 340
 341content_has_grown:
 342        up_write(&dvnode->validate_lock);
 343        afs_put_read(req);
 344        goto retry;
 345}
 346
 347/*
 348 * deal with one block in an AFS directory
 349 */
 350static int afs_dir_iterate_block(struct afs_vnode *dvnode,
 351                                 struct dir_context *ctx,
 352                                 union afs_xdr_dir_block *block,
 353                                 unsigned blkoff)
 354{
 355        union afs_xdr_dirent *dire;
 356        unsigned offset, next, curr;
 357        size_t nlen;
 358        int tmp;
 359
 360        _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block);
 361
 362        curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
 363
 364        /* walk through the block, an entry at a time */
 365        for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
 366             offset < AFS_DIR_SLOTS_PER_BLOCK;
 367             offset = next
 368             ) {
 369                next = offset + 1;
 370
 371                /* skip entries marked unused in the bitmap */
 372                if (!(block->hdr.bitmap[offset / 8] &
 373                      (1 << (offset % 8)))) {
 374                        _debug("ENT[%zu.%u]: unused",
 375                               blkoff / sizeof(union afs_xdr_dir_block), offset);
 376                        if (offset >= curr)
 377                                ctx->pos = blkoff +
 378                                        next * sizeof(union afs_xdr_dirent);
 379                        continue;
 380                }
 381
 382                /* got a valid entry */
 383                dire = &block->dirents[offset];
 384                nlen = strnlen(dire->u.name,
 385                               sizeof(*block) -
 386                               offset * sizeof(union afs_xdr_dirent));
 387
 388                _debug("ENT[%zu.%u]: %s %zu \"%s\"",
 389                       blkoff / sizeof(union afs_xdr_dir_block), offset,
 390                       (offset < curr ? "skip" : "fill"),
 391                       nlen, dire->u.name);
 392
 393                /* work out where the next possible entry is */
 394                for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_xdr_dirent)) {
 395                        if (next >= AFS_DIR_SLOTS_PER_BLOCK) {
 396                                _debug("ENT[%zu.%u]:"
 397                                       " %u travelled beyond end dir block"
 398                                       " (len %u/%zu)",
 399                                       blkoff / sizeof(union afs_xdr_dir_block),
 400                                       offset, next, tmp, nlen);
 401                                return afs_bad(dvnode, afs_file_error_dir_over_end);
 402                        }
 403                        if (!(block->hdr.bitmap[next / 8] &
 404                              (1 << (next % 8)))) {
 405                                _debug("ENT[%zu.%u]:"
 406                                       " %u unmarked extension (len %u/%zu)",
 407                                       blkoff / sizeof(union afs_xdr_dir_block),
 408                                       offset, next, tmp, nlen);
 409                                return afs_bad(dvnode, afs_file_error_dir_unmarked_ext);
 410                        }
 411
 412                        _debug("ENT[%zu.%u]: ext %u/%zu",
 413                               blkoff / sizeof(union afs_xdr_dir_block),
 414                               next, tmp, nlen);
 415                        next++;
 416                }
 417
 418                /* skip if starts before the current position */
 419                if (offset < curr)
 420                        continue;
 421
 422                /* found the next entry */
 423                if (!dir_emit(ctx, dire->u.name, nlen,
 424                              ntohl(dire->u.vnode),
 425                              (ctx->actor == afs_lookup_filldir ||
 426                               ctx->actor == afs_lookup_one_filldir)?
 427                              ntohl(dire->u.unique) : DT_UNKNOWN)) {
 428                        _leave(" = 0 [full]");
 429                        return 0;
 430                }
 431
 432                ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
 433        }
 434
 435        _leave(" = 1 [more]");
 436        return 1;
 437}
 438
 439/*
 440 * iterate through the data blob that lists the contents of an AFS directory
 441 */
 442static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
 443                           struct key *key, afs_dataversion_t *_dir_version)
 444{
 445        struct afs_vnode *dvnode = AFS_FS_I(dir);
 446        struct afs_xdr_dir_page *dbuf;
 447        union afs_xdr_dir_block *dblock;
 448        struct afs_read *req;
 449        struct page *page;
 450        unsigned blkoff, limit;
 451        int ret;
 452
 453        _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
 454
 455        if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
 456                _leave(" = -ESTALE");
 457                return -ESTALE;
 458        }
 459
 460        req = afs_read_dir(dvnode, key);
 461        if (IS_ERR(req))
 462                return PTR_ERR(req);
 463        *_dir_version = req->data_version;
 464
 465        /* round the file position up to the next entry boundary */
 466        ctx->pos += sizeof(union afs_xdr_dirent) - 1;
 467        ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1);
 468
 469        /* walk through the blocks in sequence */
 470        ret = 0;
 471        while (ctx->pos < req->actual_len) {
 472                blkoff = ctx->pos & ~(sizeof(union afs_xdr_dir_block) - 1);
 473
 474                /* Fetch the appropriate page from the directory and re-add it
 475                 * to the LRU.
 476                 */
 477                page = req->pages[blkoff / PAGE_SIZE];
 478                if (!page) {
 479                        ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
 480                        break;
 481                }
 482                mark_page_accessed(page);
 483
 484                limit = blkoff & ~(PAGE_SIZE - 1);
 485
 486                dbuf = kmap(page);
 487
 488                /* deal with the individual blocks stashed on this page */
 489                do {
 490                        dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) /
 491                                               sizeof(union afs_xdr_dir_block)];
 492                        ret = afs_dir_iterate_block(dvnode, ctx, dblock, blkoff);
 493                        if (ret != 1) {
 494                                kunmap(page);
 495                                goto out;
 496                        }
 497
 498                        blkoff += sizeof(union afs_xdr_dir_block);
 499
 500                } while (ctx->pos < dir->i_size && blkoff < limit);
 501
 502                kunmap(page);
 503                ret = 0;
 504        }
 505
 506out:
 507        up_read(&dvnode->validate_lock);
 508        afs_put_read(req);
 509        _leave(" = %d", ret);
 510        return ret;
 511}
 512
 513/*
 514 * read an AFS directory
 515 */
 516static int afs_readdir(struct file *file, struct dir_context *ctx)
 517{
 518        afs_dataversion_t dir_version;
 519
 520        return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file),
 521                               &dir_version);
 522}
 523
 524/*
 525 * Search the directory for a single name
 526 * - if afs_dir_iterate_block() spots this function, it'll pass the FID
 527 *   uniquifier through dtype
 528 */
 529static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name,
 530                                  int nlen, loff_t fpos, u64 ino, unsigned dtype)
 531{
 532        struct afs_lookup_one_cookie *cookie =
 533                container_of(ctx, struct afs_lookup_one_cookie, ctx);
 534
 535        _enter("{%s,%u},%s,%u,,%llu,%u",
 536               cookie->name.name, cookie->name.len, name, nlen,
 537               (unsigned long long) ino, dtype);
 538
 539        /* insanity checks first */
 540        BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 541        BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 542
 543        if (cookie->name.len != nlen ||
 544            memcmp(cookie->name.name, name, nlen) != 0) {
 545                _leave(" = 0 [no]");
 546                return 0;
 547        }
 548
 549        cookie->fid.vnode = ino;
 550        cookie->fid.unique = dtype;
 551        cookie->found = 1;
 552
 553        _leave(" = -1 [found]");
 554        return -1;
 555}
 556
 557/*
 558 * Do a lookup of a single name in a directory
 559 * - just returns the FID the dentry name maps to if found
 560 */
 561static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
 562                             struct afs_fid *fid, struct key *key,
 563                             afs_dataversion_t *_dir_version)
 564{
 565        struct afs_super_info *as = dir->i_sb->s_fs_info;
 566        struct afs_lookup_one_cookie cookie = {
 567                .ctx.actor = afs_lookup_one_filldir,
 568                .name = dentry->d_name,
 569                .fid.vid = as->volume->vid
 570        };
 571        int ret;
 572
 573        _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
 574
 575        /* search the directory */
 576        ret = afs_dir_iterate(dir, &cookie.ctx, key, _dir_version);
 577        if (ret < 0) {
 578                _leave(" = %d [iter]", ret);
 579                return ret;
 580        }
 581
 582        ret = -ENOENT;
 583        if (!cookie.found) {
 584                _leave(" = -ENOENT [not found]");
 585                return -ENOENT;
 586        }
 587
 588        *fid = cookie.fid;
 589        _leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique);
 590        return 0;
 591}
 592
 593/*
 594 * search the directory for a name
 595 * - if afs_dir_iterate_block() spots this function, it'll pass the FID
 596 *   uniquifier through dtype
 597 */
 598static int afs_lookup_filldir(struct dir_context *ctx, const char *name,
 599                              int nlen, loff_t fpos, u64 ino, unsigned dtype)
 600{
 601        struct afs_lookup_cookie *cookie =
 602                container_of(ctx, struct afs_lookup_cookie, ctx);
 603        int ret;
 604
 605        _enter("{%s,%u},%s,%u,,%llu,%u",
 606               cookie->name.name, cookie->name.len, name, nlen,
 607               (unsigned long long) ino, dtype);
 608
 609        /* insanity checks first */
 610        BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 611        BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 612
 613        if (cookie->found) {
 614                if (cookie->nr_fids < 50) {
 615                        cookie->fids[cookie->nr_fids].vnode     = ino;
 616                        cookie->fids[cookie->nr_fids].unique    = dtype;
 617                        cookie->nr_fids++;
 618                }
 619        } else if (cookie->name.len == nlen &&
 620                   memcmp(cookie->name.name, name, nlen) == 0) {
 621                cookie->fids[0].vnode   = ino;
 622                cookie->fids[0].unique  = dtype;
 623                cookie->found = 1;
 624                if (cookie->one_only)
 625                        return -1;
 626        }
 627
 628        ret = cookie->nr_fids >= 50 ? -1 : 0;
 629        _leave(" = %d", ret);
 630        return ret;
 631}
 632
 633/*
 634 * Do a lookup in a directory.  We make use of bulk lookup to query a slew of
 635 * files in one go and create inodes for them.  The inode of the file we were
 636 * asked for is returned.
 637 */
 638static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
 639                                   struct key *key)
 640{
 641        struct afs_lookup_cookie *cookie;
 642        struct afs_cb_interest *dcbi, *cbi = NULL;
 643        struct afs_super_info *as = dir->i_sb->s_fs_info;
 644        struct afs_status_cb *scb;
 645        struct afs_iget_data iget_data;
 646        struct afs_fs_cursor fc;
 647        struct afs_server *server;
 648        struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
 649        struct inode *inode = NULL, *ti;
 650        afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version);
 651        int ret, i;
 652
 653        _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
 654
 655        cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL);
 656        if (!cookie)
 657                return ERR_PTR(-ENOMEM);
 658
 659        cookie->ctx.actor = afs_lookup_filldir;
 660        cookie->name = dentry->d_name;
 661        cookie->nr_fids = 1; /* slot 0 is saved for the fid we actually want */
 662
 663        read_seqlock_excl(&dvnode->cb_lock);
 664        dcbi = rcu_dereference_protected(dvnode->cb_interest,
 665                                         lockdep_is_held(&dvnode->cb_lock.lock));
 666        if (dcbi) {
 667                server = dcbi->server;
 668                if (server &&
 669                    test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags))
 670                        cookie->one_only = true;
 671        }
 672        read_sequnlock_excl(&dvnode->cb_lock);
 673
 674        for (i = 0; i < 50; i++)
 675                cookie->fids[i].vid = as->volume->vid;
 676
 677        /* search the directory */
 678        ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version);
 679        if (ret < 0) {
 680                inode = ERR_PTR(ret);
 681                goto out;
 682        }
 683
 684        dentry->d_fsdata = (void *)(unsigned long)data_version;
 685
 686        inode = ERR_PTR(-ENOENT);
 687        if (!cookie->found)
 688                goto out;
 689
 690        /* Check to see if we already have an inode for the primary fid. */
 691        iget_data.fid = cookie->fids[0];
 692        iget_data.volume = dvnode->volume;
 693        iget_data.cb_v_break = dvnode->volume->cb_v_break;
 694        iget_data.cb_s_break = 0;
 695        inode = ilookup5(dir->i_sb, cookie->fids[0].vnode,
 696                         afs_iget5_test, &iget_data);
 697        if (inode)
 698                goto out;
 699
 700        /* Need space for examining all the selected files */
 701        inode = ERR_PTR(-ENOMEM);
 702        cookie->statuses = kvcalloc(cookie->nr_fids, sizeof(struct afs_status_cb),
 703                                    GFP_KERNEL);
 704        if (!cookie->statuses)
 705                goto out;
 706
 707        cookie->inodes = kcalloc(cookie->nr_fids, sizeof(struct inode *),
 708                                 GFP_KERNEL);
 709        if (!cookie->inodes)
 710                goto out_s;
 711
 712        for (i = 1; i < cookie->nr_fids; i++) {
 713                scb = &cookie->statuses[i];
 714
 715                /* Find any inodes that already exist and get their
 716                 * callback counters.
 717                 */
 718                iget_data.fid = cookie->fids[i];
 719                ti = ilookup5_nowait(dir->i_sb, iget_data.fid.vnode,
 720                                     afs_iget5_test, &iget_data);
 721                if (!IS_ERR_OR_NULL(ti)) {
 722                        vnode = AFS_FS_I(ti);
 723                        scb->cb_break = afs_calc_vnode_cb_break(vnode);
 724                        cookie->inodes[i] = ti;
 725                }
 726        }
 727
 728        /* Try FS.InlineBulkStatus first.  Abort codes for the individual
 729         * lookups contained therein are stored in the reply without aborting
 730         * the whole operation.
 731         */
 732        if (cookie->one_only)
 733                goto no_inline_bulk_status;
 734
 735        inode = ERR_PTR(-ERESTARTSYS);
 736        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
 737                while (afs_select_fileserver(&fc)) {
 738                        if (test_bit(AFS_SERVER_FL_NO_IBULK,
 739                                      &fc.cbi->server->flags)) {
 740                                fc.ac.abort_code = RX_INVALID_OPERATION;
 741                                fc.ac.error = -ECONNABORTED;
 742                                break;
 743                        }
 744                        iget_data.cb_v_break = dvnode->volume->cb_v_break;
 745                        iget_data.cb_s_break = fc.cbi->server->cb_s_break;
 746                        afs_fs_inline_bulk_status(&fc,
 747                                                  afs_v2net(dvnode),
 748                                                  cookie->fids,
 749                                                  cookie->statuses,
 750                                                  cookie->nr_fids, NULL);
 751                }
 752
 753                if (fc.ac.error == 0)
 754                        cbi = afs_get_cb_interest(fc.cbi);
 755                if (fc.ac.abort_code == RX_INVALID_OPERATION)
 756                        set_bit(AFS_SERVER_FL_NO_IBULK, &fc.cbi->server->flags);
 757                inode = ERR_PTR(afs_end_vnode_operation(&fc));
 758        }
 759
 760        if (!IS_ERR(inode))
 761                goto success;
 762        if (fc.ac.abort_code != RX_INVALID_OPERATION)
 763                goto out_c;
 764
 765no_inline_bulk_status:
 766        /* We could try FS.BulkStatus next, but this aborts the entire op if
 767         * any of the lookups fails - so, for the moment, revert to
 768         * FS.FetchStatus for just the primary fid.
 769         */
 770        inode = ERR_PTR(-ERESTARTSYS);
 771        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
 772                while (afs_select_fileserver(&fc)) {
 773                        iget_data.cb_v_break = dvnode->volume->cb_v_break;
 774                        iget_data.cb_s_break = fc.cbi->server->cb_s_break;
 775                        scb = &cookie->statuses[0];
 776                        afs_fs_fetch_status(&fc,
 777                                            afs_v2net(dvnode),
 778                                            cookie->fids,
 779                                            scb,
 780                                            NULL);
 781                }
 782
 783                if (fc.ac.error == 0)
 784                        cbi = afs_get_cb_interest(fc.cbi);
 785                inode = ERR_PTR(afs_end_vnode_operation(&fc));
 786        }
 787
 788        if (IS_ERR(inode))
 789                goto out_c;
 790
 791success:
 792        /* Turn all the files into inodes and save the first one - which is the
 793         * one we actually want.
 794         */
 795        scb = &cookie->statuses[0];
 796        if (scb->status.abort_code != 0)
 797                inode = ERR_PTR(afs_abort_to_error(scb->status.abort_code));
 798
 799        for (i = 0; i < cookie->nr_fids; i++) {
 800                struct afs_status_cb *scb = &cookie->statuses[i];
 801
 802                if (!scb->have_status && !scb->have_error)
 803                        continue;
 804
 805                if (cookie->inodes[i]) {
 806                        struct afs_vnode *iv = AFS_FS_I(cookie->inodes[i]);
 807
 808                        if (test_bit(AFS_VNODE_UNSET, &iv->flags))
 809                                continue;
 810
 811                        afs_vnode_commit_status(&fc, iv,
 812                                                scb->cb_break, NULL, scb);
 813                        continue;
 814                }
 815
 816                if (scb->status.abort_code != 0)
 817                        continue;
 818
 819                iget_data.fid = cookie->fids[i];
 820                ti = afs_iget(dir->i_sb, key, &iget_data, scb, cbi, dvnode);
 821                if (!IS_ERR(ti))
 822                        afs_cache_permit(AFS_FS_I(ti), key,
 823                                         0 /* Assume vnode->cb_break is 0 */ +
 824                                         iget_data.cb_v_break,
 825                                         scb);
 826                if (i == 0) {
 827                        inode = ti;
 828                } else {
 829                        if (!IS_ERR(ti))
 830                                iput(ti);
 831                }
 832        }
 833
 834out_c:
 835        afs_put_cb_interest(afs_v2net(dvnode), cbi);
 836        if (cookie->inodes) {
 837                for (i = 0; i < cookie->nr_fids; i++)
 838                        iput(cookie->inodes[i]);
 839                kfree(cookie->inodes);
 840        }
 841out_s:
 842        kvfree(cookie->statuses);
 843out:
 844        kfree(cookie);
 845        return inode;
 846}
 847
 848/*
 849 * Look up an entry in a directory with @sys substitution.
 850 */
 851static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry,
 852                                       struct key *key)
 853{
 854        struct afs_sysnames *subs;
 855        struct afs_net *net = afs_i2net(dir);
 856        struct dentry *ret;
 857        char *buf, *p, *name;
 858        int len, i;
 859
 860        _enter("");
 861
 862        ret = ERR_PTR(-ENOMEM);
 863        p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL);
 864        if (!buf)
 865                goto out_p;
 866        if (dentry->d_name.len > 4) {
 867                memcpy(p, dentry->d_name.name, dentry->d_name.len - 4);
 868                p += dentry->d_name.len - 4;
 869        }
 870
 871        /* There is an ordered list of substitutes that we have to try. */
 872        read_lock(&net->sysnames_lock);
 873        subs = net->sysnames;
 874        refcount_inc(&subs->usage);
 875        read_unlock(&net->sysnames_lock);
 876
 877        for (i = 0; i < subs->nr; i++) {
 878                name = subs->subs[i];
 879                len = dentry->d_name.len - 4 + strlen(name);
 880                if (len >= AFSNAMEMAX) {
 881                        ret = ERR_PTR(-ENAMETOOLONG);
 882                        goto out_s;
 883                }
 884
 885                strcpy(p, name);
 886                ret = lookup_one_len(buf, dentry->d_parent, len);
 887                if (IS_ERR(ret) || d_is_positive(ret))
 888                        goto out_s;
 889                dput(ret);
 890        }
 891
 892        /* We don't want to d_add() the @sys dentry here as we don't want to
 893         * the cached dentry to hide changes to the sysnames list.
 894         */
 895        ret = NULL;
 896out_s:
 897        afs_put_sysnames(subs);
 898        kfree(buf);
 899out_p:
 900        key_put(key);
 901        return ret;
 902}
 903
 904/*
 905 * look up an entry in a directory
 906 */
 907static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
 908                                 unsigned int flags)
 909{
 910        struct afs_vnode *dvnode = AFS_FS_I(dir);
 911        struct inode *inode;
 912        struct dentry *d;
 913        struct key *key;
 914        int ret;
 915
 916        _enter("{%llx:%llu},%p{%pd},",
 917               dvnode->fid.vid, dvnode->fid.vnode, dentry, dentry);
 918
 919        ASSERTCMP(d_inode(dentry), ==, NULL);
 920
 921        if (dentry->d_name.len >= AFSNAMEMAX) {
 922                _leave(" = -ENAMETOOLONG");
 923                return ERR_PTR(-ENAMETOOLONG);
 924        }
 925
 926        if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) {
 927                _leave(" = -ESTALE");
 928                return ERR_PTR(-ESTALE);
 929        }
 930
 931        key = afs_request_key(dvnode->volume->cell);
 932        if (IS_ERR(key)) {
 933                _leave(" = %ld [key]", PTR_ERR(key));
 934                return ERR_CAST(key);
 935        }
 936
 937        ret = afs_validate(dvnode, key);
 938        if (ret < 0) {
 939                key_put(key);
 940                _leave(" = %d [val]", ret);
 941                return ERR_PTR(ret);
 942        }
 943
 944        if (dentry->d_name.len >= 4 &&
 945            dentry->d_name.name[dentry->d_name.len - 4] == '@' &&
 946            dentry->d_name.name[dentry->d_name.len - 3] == 's' &&
 947            dentry->d_name.name[dentry->d_name.len - 2] == 'y' &&
 948            dentry->d_name.name[dentry->d_name.len - 1] == 's')
 949                return afs_lookup_atsys(dir, dentry, key);
 950
 951        afs_stat_v(dvnode, n_lookup);
 952        inode = afs_do_lookup(dir, dentry, key);
 953        key_put(key);
 954        if (inode == ERR_PTR(-ENOENT)) {
 955                inode = afs_try_auto_mntpt(dentry, dir);
 956        } else {
 957                dentry->d_fsdata =
 958                        (void *)(unsigned long)dvnode->status.data_version;
 959        }
 960        d = d_splice_alias(inode, dentry);
 961        if (!IS_ERR_OR_NULL(d)) {
 962                d->d_fsdata = dentry->d_fsdata;
 963                trace_afs_lookup(dvnode, &d->d_name,
 964                                 inode ? AFS_FS_I(inode) : NULL);
 965        } else {
 966                trace_afs_lookup(dvnode, &dentry->d_name,
 967                                 IS_ERR_OR_NULL(inode) ? NULL
 968                                 : AFS_FS_I(inode));
 969        }
 970        return d;
 971}
 972
 973/*
 974 * Check the validity of a dentry under RCU conditions.
 975 */
 976static int afs_d_revalidate_rcu(struct dentry *dentry)
 977{
 978        struct afs_vnode *dvnode, *vnode;
 979        struct dentry *parent;
 980        struct inode *dir, *inode;
 981        long dir_version, de_version;
 982
 983        _enter("%p", dentry);
 984
 985        /* Check the parent directory is still valid first. */
 986        parent = READ_ONCE(dentry->d_parent);
 987        dir = d_inode_rcu(parent);
 988        if (!dir)
 989                return -ECHILD;
 990        dvnode = AFS_FS_I(dir);
 991        if (test_bit(AFS_VNODE_DELETED, &dvnode->flags))
 992                return -ECHILD;
 993
 994        if (!afs_check_validity(dvnode))
 995                return -ECHILD;
 996
 997        /* We only need to invalidate a dentry if the server's copy changed
 998         * behind our back.  If we made the change, it's no problem.  Note that
 999         * on a 32-bit system, we only have 32 bits in the dentry to store the
1000         * version.
1001         */
1002        dir_version = (long)READ_ONCE(dvnode->status.data_version);
1003        de_version = (long)READ_ONCE(dentry->d_fsdata);
1004        if (de_version != dir_version) {
1005                dir_version = (long)READ_ONCE(dvnode->invalid_before);
1006                if (de_version - dir_version < 0)
1007                        return -ECHILD;
1008        }
1009
1010        /* Check to see if the vnode referred to by the dentry still
1011         * has a callback.
1012         */
1013        if (d_really_is_positive(dentry)) {
1014                inode = d_inode_rcu(dentry);
1015                if (inode) {
1016                        vnode = AFS_FS_I(inode);
1017                        if (!afs_check_validity(vnode))
1018                                return -ECHILD;
1019                }
1020        }
1021
1022        return 1; /* Still valid */
1023}
1024
1025/*
1026 * check that a dentry lookup hit has found a valid entry
1027 * - NOTE! the hit can be a negative hit too, so we can't assume we have an
1028 *   inode
1029 */
1030static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
1031{
1032        struct afs_vnode *vnode, *dir;
1033        struct afs_fid uninitialized_var(fid);
1034        struct dentry *parent;
1035        struct inode *inode;
1036        struct key *key;
1037        afs_dataversion_t dir_version;
1038        long de_version;
1039        int ret;
1040
1041        if (flags & LOOKUP_RCU)
1042                return afs_d_revalidate_rcu(dentry);
1043
1044        if (d_really_is_positive(dentry)) {
1045                vnode = AFS_FS_I(d_inode(dentry));
1046                _enter("{v={%llx:%llu} n=%pd fl=%lx},",
1047                       vnode->fid.vid, vnode->fid.vnode, dentry,
1048                       vnode->flags);
1049        } else {
1050                _enter("{neg n=%pd}", dentry);
1051        }
1052
1053        key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
1054        if (IS_ERR(key))
1055                key = NULL;
1056
1057        if (d_really_is_positive(dentry)) {
1058                inode = d_inode(dentry);
1059                if (inode) {
1060                        vnode = AFS_FS_I(inode);
1061                        afs_validate(vnode, key);
1062                        if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1063                                goto out_bad;
1064                }
1065        }
1066
1067        /* lock down the parent dentry so we can peer at it */
1068        parent = dget_parent(dentry);
1069        dir = AFS_FS_I(d_inode(parent));
1070
1071        /* validate the parent directory */
1072        afs_validate(dir, key);
1073
1074        if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
1075                _debug("%pd: parent dir deleted", dentry);
1076                goto out_bad_parent;
1077        }
1078
1079        /* We only need to invalidate a dentry if the server's copy changed
1080         * behind our back.  If we made the change, it's no problem.  Note that
1081         * on a 32-bit system, we only have 32 bits in the dentry to store the
1082         * version.
1083         */
1084        dir_version = dir->status.data_version;
1085        de_version = (long)dentry->d_fsdata;
1086        if (de_version == (long)dir_version)
1087                goto out_valid_noupdate;
1088
1089        dir_version = dir->invalid_before;
1090        if (de_version - (long)dir_version >= 0)
1091                goto out_valid;
1092
1093        _debug("dir modified");
1094        afs_stat_v(dir, n_reval);
1095
1096        /* search the directory for this vnode */
1097        ret = afs_do_lookup_one(&dir->vfs_inode, dentry, &fid, key, &dir_version);
1098        switch (ret) {
1099        case 0:
1100                /* the filename maps to something */
1101                if (d_really_is_negative(dentry))
1102                        goto out_bad_parent;
1103                inode = d_inode(dentry);
1104                if (is_bad_inode(inode)) {
1105                        printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
1106                               dentry);
1107                        goto out_bad_parent;
1108                }
1109
1110                vnode = AFS_FS_I(inode);
1111
1112                /* if the vnode ID has changed, then the dirent points to a
1113                 * different file */
1114                if (fid.vnode != vnode->fid.vnode) {
1115                        _debug("%pd: dirent changed [%llu != %llu]",
1116                               dentry, fid.vnode,
1117                               vnode->fid.vnode);
1118                        goto not_found;
1119                }
1120
1121                /* if the vnode ID uniqifier has changed, then the file has
1122                 * been deleted and replaced, and the original vnode ID has
1123                 * been reused */
1124                if (fid.unique != vnode->fid.unique) {
1125                        _debug("%pd: file deleted (uq %u -> %u I:%u)",
1126                               dentry, fid.unique,
1127                               vnode->fid.unique,
1128                               vnode->vfs_inode.i_generation);
1129                        write_seqlock(&vnode->cb_lock);
1130                        set_bit(AFS_VNODE_DELETED, &vnode->flags);
1131                        write_sequnlock(&vnode->cb_lock);
1132                        goto not_found;
1133                }
1134                goto out_valid;
1135
1136        case -ENOENT:
1137                /* the filename is unknown */
1138                _debug("%pd: dirent not found", dentry);
1139                if (d_really_is_positive(dentry))
1140                        goto not_found;
1141                goto out_valid;
1142
1143        default:
1144                _debug("failed to iterate dir %pd: %d",
1145                       parent, ret);
1146                goto out_bad_parent;
1147        }
1148
1149out_valid:
1150        dentry->d_fsdata = (void *)(unsigned long)dir_version;
1151out_valid_noupdate:
1152        dput(parent);
1153        key_put(key);
1154        _leave(" = 1 [valid]");
1155        return 1;
1156
1157        /* the dirent, if it exists, now points to a different vnode */
1158not_found:
1159        spin_lock(&dentry->d_lock);
1160        dentry->d_flags |= DCACHE_NFSFS_RENAMED;
1161        spin_unlock(&dentry->d_lock);
1162
1163out_bad_parent:
1164        _debug("dropping dentry %pd2", dentry);
1165        dput(parent);
1166out_bad:
1167        key_put(key);
1168
1169        _leave(" = 0 [bad]");
1170        return 0;
1171}
1172
1173/*
1174 * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
1175 * sleep)
1176 * - called from dput() when d_count is going to 0.
1177 * - return 1 to request dentry be unhashed, 0 otherwise
1178 */
1179static int afs_d_delete(const struct dentry *dentry)
1180{
1181        _enter("%pd", dentry);
1182
1183        if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1184                goto zap;
1185
1186        if (d_really_is_positive(dentry) &&
1187            (test_bit(AFS_VNODE_DELETED,   &AFS_FS_I(d_inode(dentry))->flags) ||
1188             test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
1189                goto zap;
1190
1191        _leave(" = 0 [keep]");
1192        return 0;
1193
1194zap:
1195        _leave(" = 1 [zap]");
1196        return 1;
1197}
1198
1199/*
1200 * Clean up sillyrename files on dentry removal.
1201 */
1202static void afs_d_iput(struct dentry *dentry, struct inode *inode)
1203{
1204        if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1205                afs_silly_iput(dentry, inode);
1206        iput(inode);
1207}
1208
1209/*
1210 * handle dentry release
1211 */
1212void afs_d_release(struct dentry *dentry)
1213{
1214        _enter("%pd", dentry);
1215}
1216
1217/*
1218 * Create a new inode for create/mkdir/symlink
1219 */
1220static void afs_vnode_new_inode(struct afs_fs_cursor *fc,
1221                                struct dentry *new_dentry,
1222                                struct afs_iget_data *new_data,
1223                                struct afs_status_cb *new_scb)
1224{
1225        struct afs_vnode *vnode;
1226        struct inode *inode;
1227
1228        if (fc->ac.error < 0)
1229                return;
1230
1231        inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key,
1232                         new_data, new_scb, fc->cbi, fc->vnode);
1233        if (IS_ERR(inode)) {
1234                /* ENOMEM or EINTR at a really inconvenient time - just abandon
1235                 * the new directory on the server.
1236                 */
1237                fc->ac.error = PTR_ERR(inode);
1238                return;
1239        }
1240
1241        vnode = AFS_FS_I(inode);
1242        set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
1243        if (fc->ac.error == 0)
1244                afs_cache_permit(vnode, fc->key, vnode->cb_break, new_scb);
1245        d_instantiate(new_dentry, inode);
1246}
1247
1248static void afs_prep_for_new_inode(struct afs_fs_cursor *fc,
1249                                   struct afs_iget_data *iget_data)
1250{
1251        iget_data->volume = fc->vnode->volume;
1252        iget_data->cb_v_break = fc->vnode->volume->cb_v_break;
1253        iget_data->cb_s_break = fc->cbi->server->cb_s_break;
1254}
1255
1256/*
1257 * Note that a dentry got changed.  We need to set d_fsdata to the data version
1258 * number derived from the result of the operation.  It doesn't matter if
1259 * d_fsdata goes backwards as we'll just revalidate.
1260 */
1261static void afs_update_dentry_version(struct afs_fs_cursor *fc,
1262                                      struct dentry *dentry,
1263                                      struct afs_status_cb *scb)
1264{
1265        if (fc->ac.error == 0)
1266                dentry->d_fsdata =
1267                        (void *)(unsigned long)scb->status.data_version;
1268}
1269
1270/*
1271 * create a directory on an AFS filesystem
1272 */
1273static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1274{
1275        struct afs_iget_data iget_data;
1276        struct afs_status_cb *scb;
1277        struct afs_fs_cursor fc;
1278        struct afs_vnode *dvnode = AFS_FS_I(dir);
1279        struct key *key;
1280        int ret;
1281
1282        mode |= S_IFDIR;
1283
1284        _enter("{%llx:%llu},{%pd},%ho",
1285               dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1286
1287        ret = -ENOMEM;
1288        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1289        if (!scb)
1290                goto error;
1291
1292        key = afs_request_key(dvnode->volume->cell);
1293        if (IS_ERR(key)) {
1294                ret = PTR_ERR(key);
1295                goto error_scb;
1296        }
1297
1298        ret = -ERESTARTSYS;
1299        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1300                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1301
1302                while (afs_select_fileserver(&fc)) {
1303                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1304                        afs_prep_for_new_inode(&fc, &iget_data);
1305                        afs_fs_create(&fc, dentry->d_name.name, mode,
1306                                      &scb[0], &iget_data.fid, &scb[1]);
1307                }
1308
1309                afs_check_for_remote_deletion(&fc, dvnode);
1310                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1311                                        &data_version, &scb[0]);
1312                afs_update_dentry_version(&fc, dentry, &scb[0]);
1313                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1314                ret = afs_end_vnode_operation(&fc);
1315                if (ret < 0)
1316                        goto error_key;
1317        } else {
1318                goto error_key;
1319        }
1320
1321        if (ret == 0 &&
1322            test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1323                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1324                                 afs_edit_dir_for_create);
1325
1326        key_put(key);
1327        kfree(scb);
1328        _leave(" = 0");
1329        return 0;
1330
1331error_key:
1332        key_put(key);
1333error_scb:
1334        kfree(scb);
1335error:
1336        d_drop(dentry);
1337        _leave(" = %d", ret);
1338        return ret;
1339}
1340
1341/*
1342 * Remove a subdir from a directory.
1343 */
1344static void afs_dir_remove_subdir(struct dentry *dentry)
1345{
1346        if (d_really_is_positive(dentry)) {
1347                struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1348
1349                clear_nlink(&vnode->vfs_inode);
1350                set_bit(AFS_VNODE_DELETED, &vnode->flags);
1351                clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
1352                clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
1353        }
1354}
1355
1356/*
1357 * remove a directory from an AFS filesystem
1358 */
1359static int afs_rmdir(struct inode *dir, struct dentry *dentry)
1360{
1361        struct afs_status_cb *scb;
1362        struct afs_fs_cursor fc;
1363        struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL;
1364        struct key *key;
1365        int ret;
1366
1367        _enter("{%llx:%llu},{%pd}",
1368               dvnode->fid.vid, dvnode->fid.vnode, dentry);
1369
1370        scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL);
1371        if (!scb)
1372                return -ENOMEM;
1373
1374        key = afs_request_key(dvnode->volume->cell);
1375        if (IS_ERR(key)) {
1376                ret = PTR_ERR(key);
1377                goto error;
1378        }
1379
1380        /* Try to make sure we have a callback promise on the victim. */
1381        if (d_really_is_positive(dentry)) {
1382                vnode = AFS_FS_I(d_inode(dentry));
1383                ret = afs_validate(vnode, key);
1384                if (ret < 0)
1385                        goto error_key;
1386        }
1387
1388        if (vnode) {
1389                ret = down_write_killable(&vnode->rmdir_lock);
1390                if (ret < 0)
1391                        goto error_key;
1392        }
1393
1394        ret = -ERESTARTSYS;
1395        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1396                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1397
1398                while (afs_select_fileserver(&fc)) {
1399                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1400                        afs_fs_remove(&fc, vnode, dentry->d_name.name, true, scb);
1401                }
1402
1403                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1404                                        &data_version, scb);
1405                afs_update_dentry_version(&fc, dentry, scb);
1406                ret = afs_end_vnode_operation(&fc);
1407                if (ret == 0) {
1408                        afs_dir_remove_subdir(dentry);
1409                        if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1410                                afs_edit_dir_remove(dvnode, &dentry->d_name,
1411                                                    afs_edit_dir_for_rmdir);
1412                }
1413        }
1414
1415        if (vnode)
1416                up_write(&vnode->rmdir_lock);
1417error_key:
1418        key_put(key);
1419error:
1420        kfree(scb);
1421        return ret;
1422}
1423
1424/*
1425 * Remove a link to a file or symlink from a directory.
1426 *
1427 * If the file was not deleted due to excess hard links, the fileserver will
1428 * break the callback promise on the file - if it had one - before it returns
1429 * to us, and if it was deleted, it won't
1430 *
1431 * However, if we didn't have a callback promise outstanding, or it was
1432 * outstanding on a different server, then it won't break it either...
1433 */
1434static int afs_dir_remove_link(struct afs_vnode *dvnode, struct dentry *dentry,
1435                               struct key *key)
1436{
1437        int ret = 0;
1438
1439        if (d_really_is_positive(dentry)) {
1440                struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1441
1442                if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
1443                        /* Already done */
1444                } else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
1445                        write_seqlock(&vnode->cb_lock);
1446                        drop_nlink(&vnode->vfs_inode);
1447                        if (vnode->vfs_inode.i_nlink == 0) {
1448                                set_bit(AFS_VNODE_DELETED, &vnode->flags);
1449                                __afs_break_callback(vnode, afs_cb_break_for_unlink);
1450                        }
1451                        write_sequnlock(&vnode->cb_lock);
1452                        ret = 0;
1453                } else {
1454                        afs_break_callback(vnode, afs_cb_break_for_unlink);
1455
1456                        if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1457                                kdebug("AFS_VNODE_DELETED");
1458
1459                        ret = afs_validate(vnode, key);
1460                        if (ret == -ESTALE)
1461                                ret = 0;
1462                }
1463                _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret);
1464        }
1465
1466        return ret;
1467}
1468
1469/*
1470 * Remove a file or symlink from an AFS filesystem.
1471 */
1472static int afs_unlink(struct inode *dir, struct dentry *dentry)
1473{
1474        struct afs_fs_cursor fc;
1475        struct afs_status_cb *scb;
1476        struct afs_vnode *dvnode = AFS_FS_I(dir);
1477        struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1478        struct key *key;
1479        bool need_rehash = false;
1480        int ret;
1481
1482        _enter("{%llx:%llu},{%pd}",
1483               dvnode->fid.vid, dvnode->fid.vnode, dentry);
1484
1485        if (dentry->d_name.len >= AFSNAMEMAX)
1486                return -ENAMETOOLONG;
1487
1488        ret = -ENOMEM;
1489        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1490        if (!scb)
1491                goto error;
1492
1493        key = afs_request_key(dvnode->volume->cell);
1494        if (IS_ERR(key)) {
1495                ret = PTR_ERR(key);
1496                goto error_scb;
1497        }
1498
1499        /* Try to make sure we have a callback promise on the victim. */
1500        ret = afs_validate(vnode, key);
1501        if (ret < 0)
1502                goto error_key;
1503
1504        spin_lock(&dentry->d_lock);
1505        if (d_count(dentry) > 1) {
1506                spin_unlock(&dentry->d_lock);
1507                /* Start asynchronous writeout of the inode */
1508                write_inode_now(d_inode(dentry), 0);
1509                ret = afs_sillyrename(dvnode, vnode, dentry, key);
1510                goto error_key;
1511        }
1512        if (!d_unhashed(dentry)) {
1513                /* Prevent a race with RCU lookup. */
1514                __d_drop(dentry);
1515                need_rehash = true;
1516        }
1517        spin_unlock(&dentry->d_lock);
1518
1519        ret = -ERESTARTSYS;
1520        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1521                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1522                afs_dataversion_t data_version_2 = vnode->status.data_version;
1523
1524                while (afs_select_fileserver(&fc)) {
1525                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1526                        fc.cb_break_2 = afs_calc_vnode_cb_break(vnode);
1527
1528                        if (test_bit(AFS_SERVER_FL_IS_YFS, &fc.cbi->server->flags) &&
1529                            !test_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags)) {
1530                                yfs_fs_remove_file2(&fc, vnode, dentry->d_name.name,
1531                                                    &scb[0], &scb[1]);
1532                                if (fc.ac.error != -ECONNABORTED ||
1533                                    fc.ac.abort_code != RXGEN_OPCODE)
1534                                        continue;
1535                                set_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags);
1536                        }
1537
1538                        afs_fs_remove(&fc, vnode, dentry->d_name.name, false, &scb[0]);
1539                }
1540
1541                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1542                                        &data_version, &scb[0]);
1543                afs_vnode_commit_status(&fc, vnode, fc.cb_break_2,
1544                                        &data_version_2, &scb[1]);
1545                afs_update_dentry_version(&fc, dentry, &scb[0]);
1546                ret = afs_end_vnode_operation(&fc);
1547                if (ret == 0 && !(scb[1].have_status || scb[1].have_error))
1548                        ret = afs_dir_remove_link(dvnode, dentry, key);
1549                if (ret == 0 &&
1550                    test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1551                        afs_edit_dir_remove(dvnode, &dentry->d_name,
1552                                            afs_edit_dir_for_unlink);
1553        }
1554
1555        if (need_rehash && ret < 0 && ret != -ENOENT)
1556                d_rehash(dentry);
1557
1558error_key:
1559        key_put(key);
1560error_scb:
1561        kfree(scb);
1562error:
1563        _leave(" = %d", ret);
1564        return ret;
1565}
1566
1567/*
1568 * create a regular file on an AFS filesystem
1569 */
1570static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
1571                      bool excl)
1572{
1573        struct afs_iget_data iget_data;
1574        struct afs_fs_cursor fc;
1575        struct afs_status_cb *scb;
1576        struct afs_vnode *dvnode = AFS_FS_I(dir);
1577        struct key *key;
1578        int ret;
1579
1580        mode |= S_IFREG;
1581
1582        _enter("{%llx:%llu},{%pd},%ho,",
1583               dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1584
1585        ret = -ENAMETOOLONG;
1586        if (dentry->d_name.len >= AFSNAMEMAX)
1587                goto error;
1588
1589        key = afs_request_key(dvnode->volume->cell);
1590        if (IS_ERR(key)) {
1591                ret = PTR_ERR(key);
1592                goto error;
1593        }
1594
1595        ret = -ENOMEM;
1596        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1597        if (!scb)
1598                goto error_scb;
1599
1600        ret = -ERESTARTSYS;
1601        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1602                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1603
1604                while (afs_select_fileserver(&fc)) {
1605                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1606                        afs_prep_for_new_inode(&fc, &iget_data);
1607                        afs_fs_create(&fc, dentry->d_name.name, mode,
1608                                      &scb[0], &iget_data.fid, &scb[1]);
1609                }
1610
1611                afs_check_for_remote_deletion(&fc, dvnode);
1612                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1613                                        &data_version, &scb[0]);
1614                afs_update_dentry_version(&fc, dentry, &scb[0]);
1615                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1616                ret = afs_end_vnode_operation(&fc);
1617                if (ret < 0)
1618                        goto error_key;
1619        } else {
1620                goto error_key;
1621        }
1622
1623        if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1624                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1625                                 afs_edit_dir_for_create);
1626
1627        kfree(scb);
1628        key_put(key);
1629        _leave(" = 0");
1630        return 0;
1631
1632error_scb:
1633        kfree(scb);
1634error_key:
1635        key_put(key);
1636error:
1637        d_drop(dentry);
1638        _leave(" = %d", ret);
1639        return ret;
1640}
1641
1642/*
1643 * create a hard link between files in an AFS filesystem
1644 */
1645static int afs_link(struct dentry *from, struct inode *dir,
1646                    struct dentry *dentry)
1647{
1648        struct afs_fs_cursor fc;
1649        struct afs_status_cb *scb;
1650        struct afs_vnode *dvnode = AFS_FS_I(dir);
1651        struct afs_vnode *vnode = AFS_FS_I(d_inode(from));
1652        struct key *key;
1653        int ret;
1654
1655        _enter("{%llx:%llu},{%llx:%llu},{%pd}",
1656               vnode->fid.vid, vnode->fid.vnode,
1657               dvnode->fid.vid, dvnode->fid.vnode,
1658               dentry);
1659
1660        ret = -ENAMETOOLONG;
1661        if (dentry->d_name.len >= AFSNAMEMAX)
1662                goto error;
1663
1664        ret = -ENOMEM;
1665        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1666        if (!scb)
1667                goto error;
1668
1669        key = afs_request_key(dvnode->volume->cell);
1670        if (IS_ERR(key)) {
1671                ret = PTR_ERR(key);
1672                goto error_scb;
1673        }
1674
1675        ret = -ERESTARTSYS;
1676        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1677                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1678
1679                if (mutex_lock_interruptible_nested(&vnode->io_lock, 1) < 0) {
1680                        afs_end_vnode_operation(&fc);
1681                        goto error_key;
1682                }
1683
1684                while (afs_select_fileserver(&fc)) {
1685                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1686                        fc.cb_break_2 = afs_calc_vnode_cb_break(vnode);
1687                        afs_fs_link(&fc, vnode, dentry->d_name.name,
1688                                    &scb[0], &scb[1]);
1689                }
1690
1691                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1692                                        &data_version, &scb[0]);
1693                afs_vnode_commit_status(&fc, vnode, fc.cb_break_2,
1694                                        NULL, &scb[1]);
1695                ihold(&vnode->vfs_inode);
1696                afs_update_dentry_version(&fc, dentry, &scb[0]);
1697                d_instantiate(dentry, &vnode->vfs_inode);
1698
1699                mutex_unlock(&vnode->io_lock);
1700                ret = afs_end_vnode_operation(&fc);
1701                if (ret < 0)
1702                        goto error_key;
1703        } else {
1704                goto error_key;
1705        }
1706
1707        if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1708                afs_edit_dir_add(dvnode, &dentry->d_name, &vnode->fid,
1709                                 afs_edit_dir_for_link);
1710
1711        key_put(key);
1712        kfree(scb);
1713        _leave(" = 0");
1714        return 0;
1715
1716error_key:
1717        key_put(key);
1718error_scb:
1719        kfree(scb);
1720error:
1721        d_drop(dentry);
1722        _leave(" = %d", ret);
1723        return ret;
1724}
1725
1726/*
1727 * create a symlink in an AFS filesystem
1728 */
1729static int afs_symlink(struct inode *dir, struct dentry *dentry,
1730                       const char *content)
1731{
1732        struct afs_iget_data iget_data;
1733        struct afs_fs_cursor fc;
1734        struct afs_status_cb *scb;
1735        struct afs_vnode *dvnode = AFS_FS_I(dir);
1736        struct key *key;
1737        int ret;
1738
1739        _enter("{%llx:%llu},{%pd},%s",
1740               dvnode->fid.vid, dvnode->fid.vnode, dentry,
1741               content);
1742
1743        ret = -ENAMETOOLONG;
1744        if (dentry->d_name.len >= AFSNAMEMAX)
1745                goto error;
1746
1747        ret = -EINVAL;
1748        if (strlen(content) >= AFSPATHMAX)
1749                goto error;
1750
1751        ret = -ENOMEM;
1752        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1753        if (!scb)
1754                goto error;
1755
1756        key = afs_request_key(dvnode->volume->cell);
1757        if (IS_ERR(key)) {
1758                ret = PTR_ERR(key);
1759                goto error_scb;
1760        }
1761
1762        ret = -ERESTARTSYS;
1763        if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1764                afs_dataversion_t data_version = dvnode->status.data_version + 1;
1765
1766                while (afs_select_fileserver(&fc)) {
1767                        fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1768                        afs_prep_for_new_inode(&fc, &iget_data);
1769                        afs_fs_symlink(&fc, dentry->d_name.name, content,
1770                                       &scb[0], &iget_data.fid, &scb[1]);
1771                }
1772
1773                afs_check_for_remote_deletion(&fc, dvnode);
1774                afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1775                                        &data_version, &scb[0]);
1776                afs_update_dentry_version(&fc, dentry, &scb[0]);
1777                afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1778                ret = afs_end_vnode_operation(&fc);
1779                if (ret < 0)
1780                        goto error_key;
1781        } else {
1782                goto error_key;
1783        }
1784
1785        if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1786                afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1787                                 afs_edit_dir_for_symlink);
1788
1789        key_put(key);
1790        kfree(scb);
1791        _leave(" = 0");
1792        return 0;
1793
1794error_key:
1795        key_put(key);
1796error_scb:
1797        kfree(scb);
1798error:
1799        d_drop(dentry);
1800        _leave(" = %d", ret);
1801        return ret;
1802}
1803
1804/*
1805 * rename a file in an AFS filesystem and/or move it between directories
1806 */
1807static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
1808                      struct inode *new_dir, struct dentry *new_dentry,
1809                      unsigned int flags)
1810{
1811        struct afs_fs_cursor fc;
1812        struct afs_status_cb *scb;
1813        struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
1814        struct dentry *tmp = NULL, *rehash = NULL;
1815        struct inode *new_inode;
1816        struct key *key;
1817        bool new_negative = d_is_negative(new_dentry);
1818        int ret;
1819
1820        if (flags)
1821                return -EINVAL;
1822
1823        /* Don't allow silly-rename files be moved around. */
1824        if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED)
1825                return -EINVAL;
1826
1827        vnode = AFS_FS_I(d_inode(old_dentry));
1828        orig_dvnode = AFS_FS_I(old_dir);
1829        new_dvnode = AFS_FS_I(new_dir);
1830
1831        _enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%pd}",
1832               orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
1833               vnode->fid.vid, vnode->fid.vnode,
1834               new_dvnode->fid.vid, new_dvnode->fid.vnode,
1835               new_dentry);
1836
1837        ret = -ENOMEM;
1838        scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1839        if (!scb)
1840                goto error;
1841
1842        key = afs_request_key(orig_dvnode->volume->cell);
1843        if (IS_ERR(key)) {
1844                ret = PTR_ERR(key);
1845                goto error_scb;
1846        }
1847
1848        /* For non-directories, check whether the target is busy and if so,
1849         * make a copy of the dentry and then do a silly-rename.  If the
1850         * silly-rename succeeds, the copied dentry is hashed and becomes the
1851         * new target.
1852         */
1853        if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) {
1854                /* To prevent any new references to the target during the
1855                 * rename, we unhash the dentry in advance.
1856                 */
1857                if (!d_unhashed(new_dentry)) {
1858                        d_drop(new_dentry);
1859                        rehash = new_dentry;
1860                }
1861
1862                if (d_count(new_dentry) > 2) {
1863                        /* copy the target dentry's name */
1864                        ret = -ENOMEM;
1865                        tmp = d_alloc(new_dentry->d_parent,
1866                                      &new_dentry->d_name);
1867                        if (!tmp)
1868                                goto error_rehash;
1869
1870                        ret = afs_sillyrename(new_dvnode,
1871                                              AFS_FS_I(d_inode(new_dentry)),
1872                                              new_dentry, key);
1873                        if (ret)
1874                                goto error_rehash;
1875
1876                        new_dentry = tmp;
1877                        rehash = NULL;
1878                        new_negative = true;
1879                }
1880        }
1881
1882        /* This bit is potentially nasty as there's a potential race with
1883         * afs_d_revalidate{,_rcu}().  We have to change d_fsdata on the dentry
1884         * to reflect it's new parent's new data_version after the op, but
1885         * d_revalidate may see old_dentry between the op having taken place
1886         * and the version being updated.
1887         *
1888         * So drop the old_dentry for now to make other threads go through
1889         * lookup instead - which we hold a lock against.
1890         */
1891        d_drop(old_dentry);
1892
1893        ret = -ERESTARTSYS;
1894        if (afs_begin_vnode_operation(&fc, orig_dvnode, key, true)) {
1895                afs_dataversion_t orig_data_version;
1896                afs_dataversion_t new_data_version;
1897                struct afs_status_cb *new_scb = &scb[1];
1898
1899                orig_data_version = orig_dvnode->status.data_version + 1;
1900
1901                if (orig_dvnode != new_dvnode) {
1902                        if (mutex_lock_interruptible_nested(&new_dvnode->io_lock, 1) < 0) {
1903                                afs_end_vnode_operation(&fc);
1904                                goto error_rehash_old;
1905                        }
1906                        new_data_version = new_dvnode->status.data_version + 1;
1907                } else {
1908                        new_data_version = orig_data_version;
1909                        new_scb = &scb[0];
1910                }
1911
1912                while (afs_select_fileserver(&fc)) {
1913                        fc.cb_break = afs_calc_vnode_cb_break(orig_dvnode);
1914                        fc.cb_break_2 = afs_calc_vnode_cb_break(new_dvnode);
1915                        afs_fs_rename(&fc, old_dentry->d_name.name,
1916                                      new_dvnode, new_dentry->d_name.name,
1917                                      &scb[0], new_scb);
1918                }
1919
1920                afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break,
1921                                        &orig_data_version, &scb[0]);
1922                if (new_dvnode != orig_dvnode) {
1923                        afs_vnode_commit_status(&fc, new_dvnode, fc.cb_break_2,
1924                                                &new_data_version, &scb[1]);
1925                        mutex_unlock(&new_dvnode->io_lock);
1926                }
1927                ret = afs_end_vnode_operation(&fc);
1928                if (ret < 0)
1929                        goto error_rehash_old;
1930        }
1931
1932        if (ret == 0) {
1933                if (rehash)
1934                        d_rehash(rehash);
1935                if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags))
1936                    afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
1937                                        afs_edit_dir_for_rename_0);
1938
1939                if (!new_negative &&
1940                    test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
1941                        afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
1942                                            afs_edit_dir_for_rename_1);
1943
1944                if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
1945                        afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
1946                                         &vnode->fid, afs_edit_dir_for_rename_2);
1947
1948                new_inode = d_inode(new_dentry);
1949                if (new_inode) {
1950                        spin_lock(&new_inode->i_lock);
1951                        if (new_inode->i_nlink > 0)
1952                                drop_nlink(new_inode);
1953                        spin_unlock(&new_inode->i_lock);
1954                }
1955
1956                /* Now we can update d_fsdata on the dentries to reflect their
1957                 * new parent's data_version.
1958                 *
1959                 * Note that if we ever implement RENAME_EXCHANGE, we'll have
1960                 * to update both dentries with opposing dir versions.
1961                 */
1962                if (new_dvnode != orig_dvnode) {
1963                        afs_update_dentry_version(&fc, old_dentry, &scb[1]);
1964                        afs_update_dentry_version(&fc, new_dentry, &scb[1]);
1965                } else {
1966                        afs_update_dentry_version(&fc, old_dentry, &scb[0]);
1967                        afs_update_dentry_version(&fc, new_dentry, &scb[0]);
1968                }
1969                d_move(old_dentry, new_dentry);
1970                goto error_tmp;
1971        }
1972
1973error_rehash_old:
1974        d_rehash(new_dentry);
1975error_rehash:
1976        if (rehash)
1977                d_rehash(rehash);
1978error_tmp:
1979        if (tmp)
1980                dput(tmp);
1981        key_put(key);
1982error_scb:
1983        kfree(scb);
1984error:
1985        _leave(" = %d", ret);
1986        return ret;
1987}
1988
1989/*
1990 * Release a directory page and clean up its private state if it's not busy
1991 * - return true if the page can now be released, false if not
1992 */
1993static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags)
1994{
1995        struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
1996
1997        _enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, page->index);
1998
1999        set_page_private(page, 0);
2000        ClearPagePrivate(page);
2001
2002        /* The directory will need reloading. */
2003        if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2004                afs_stat_v(dvnode, n_relpg);
2005        return 1;
2006}
2007
2008/*
2009 * invalidate part or all of a page
2010 * - release a page and clean up its private data if offset is 0 (indicating
2011 *   the entire page)
2012 */
2013static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
2014                                   unsigned int length)
2015{
2016        struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
2017
2018        _enter("{%lu},%u,%u", page->index, offset, length);
2019
2020        BUG_ON(!PageLocked(page));
2021
2022        /* The directory will need reloading. */
2023        if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2024                afs_stat_v(dvnode, n_inval);
2025
2026        /* we clean up only if the entire page is being invalidated */
2027        if (offset == 0 && length == PAGE_SIZE) {
2028                set_page_private(page, 0);
2029                ClearPagePrivate(page);
2030        }
2031}
2032