Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* dir.c: AFS filesystem directory handling |
| 2 | * |
| 3 | * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/sched.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/fs.h> |
| 18 | #include <linux/pagemap.h> |
| 19 | #include <linux/smp_lock.h> |
| 20 | #include "vnode.h" |
| 21 | #include "volume.h" |
| 22 | #include <rxrpc/call.h> |
| 23 | #include "super.h" |
| 24 | #include "internal.h" |
| 25 | |
| 26 | static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry, |
| 27 | struct nameidata *nd); |
| 28 | static int afs_dir_open(struct inode *inode, struct file *file); |
| 29 | static int afs_dir_readdir(struct file *file, void *dirent, filldir_t filldir); |
| 30 | static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd); |
| 31 | static int afs_d_delete(struct dentry *dentry); |
| 32 | static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen, |
| 33 | loff_t fpos, ino_t ino, unsigned dtype); |
| 34 | |
| 35 | struct file_operations afs_dir_file_operations = { |
| 36 | .open = afs_dir_open, |
| 37 | .readdir = afs_dir_readdir, |
| 38 | }; |
| 39 | |
| 40 | struct inode_operations afs_dir_inode_operations = { |
| 41 | .lookup = afs_dir_lookup, |
| 42 | .getattr = afs_inode_getattr, |
| 43 | #if 0 /* TODO */ |
| 44 | .create = afs_dir_create, |
| 45 | .link = afs_dir_link, |
| 46 | .unlink = afs_dir_unlink, |
| 47 | .symlink = afs_dir_symlink, |
| 48 | .mkdir = afs_dir_mkdir, |
| 49 | .rmdir = afs_dir_rmdir, |
| 50 | .mknod = afs_dir_mknod, |
| 51 | .rename = afs_dir_rename, |
| 52 | #endif |
| 53 | }; |
| 54 | |
| 55 | static struct dentry_operations afs_fs_dentry_operations = { |
| 56 | .d_revalidate = afs_d_revalidate, |
| 57 | .d_delete = afs_d_delete, |
| 58 | }; |
| 59 | |
| 60 | #define AFS_DIR_HASHTBL_SIZE 128 |
| 61 | #define AFS_DIR_DIRENT_SIZE 32 |
| 62 | #define AFS_DIRENT_PER_BLOCK 64 |
| 63 | |
| 64 | union afs_dirent { |
| 65 | struct { |
| 66 | uint8_t valid; |
| 67 | uint8_t unused[1]; |
| 68 | __be16 hash_next; |
| 69 | __be32 vnode; |
| 70 | __be32 unique; |
| 71 | uint8_t name[16]; |
| 72 | uint8_t overflow[4]; /* if any char of the name (inc |
| 73 | * NUL) reaches here, consume |
| 74 | * the next dirent too */ |
| 75 | } u; |
| 76 | uint8_t extended_name[32]; |
| 77 | }; |
| 78 | |
| 79 | /* AFS directory page header (one at the beginning of every 2048-byte chunk) */ |
| 80 | struct afs_dir_pagehdr { |
| 81 | __be16 npages; |
| 82 | __be16 magic; |
| 83 | #define AFS_DIR_MAGIC htons(1234) |
| 84 | uint8_t nentries; |
| 85 | uint8_t bitmap[8]; |
| 86 | uint8_t pad[19]; |
| 87 | }; |
| 88 | |
| 89 | /* directory block layout */ |
| 90 | union afs_dir_block { |
| 91 | |
| 92 | struct afs_dir_pagehdr pagehdr; |
| 93 | |
| 94 | struct { |
| 95 | struct afs_dir_pagehdr pagehdr; |
| 96 | uint8_t alloc_ctrs[128]; |
| 97 | /* dir hash table */ |
| 98 | uint16_t hashtable[AFS_DIR_HASHTBL_SIZE]; |
| 99 | } hdr; |
| 100 | |
| 101 | union afs_dirent dirents[AFS_DIRENT_PER_BLOCK]; |
| 102 | }; |
| 103 | |
| 104 | /* layout on a linux VM page */ |
| 105 | struct afs_dir_page { |
| 106 | union afs_dir_block blocks[PAGE_SIZE / sizeof(union afs_dir_block)]; |
| 107 | }; |
| 108 | |
| 109 | struct afs_dir_lookup_cookie { |
| 110 | struct afs_fid fid; |
| 111 | const char *name; |
| 112 | size_t nlen; |
| 113 | int found; |
| 114 | }; |
| 115 | |
| 116 | /*****************************************************************************/ |
| 117 | /* |
| 118 | * check that a directory page is valid |
| 119 | */ |
| 120 | static inline void afs_dir_check_page(struct inode *dir, struct page *page) |
| 121 | { |
| 122 | struct afs_dir_page *dbuf; |
| 123 | loff_t latter; |
| 124 | int tmp, qty; |
| 125 | |
| 126 | #if 0 |
| 127 | /* check the page count */ |
| 128 | qty = desc.size / sizeof(dbuf->blocks[0]); |
| 129 | if (qty == 0) |
| 130 | goto error; |
| 131 | |
| 132 | if (page->index==0 && qty!=ntohs(dbuf->blocks[0].pagehdr.npages)) { |
| 133 | printk("kAFS: %s(%lu): wrong number of dir blocks %d!=%hu\n", |
| 134 | __FUNCTION__,dir->i_ino,qty,ntohs(dbuf->blocks[0].pagehdr.npages)); |
| 135 | goto error; |
| 136 | } |
| 137 | #endif |
| 138 | |
| 139 | /* determine how many magic numbers there should be in this page */ |
| 140 | latter = dir->i_size - (page->index << PAGE_CACHE_SHIFT); |
| 141 | if (latter >= PAGE_SIZE) |
| 142 | qty = PAGE_SIZE; |
| 143 | else |
| 144 | qty = latter; |
| 145 | qty /= sizeof(union afs_dir_block); |
| 146 | |
| 147 | /* check them */ |
| 148 | dbuf = page_address(page); |
| 149 | for (tmp = 0; tmp < qty; tmp++) { |
| 150 | if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) { |
| 151 | printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n", |
| 152 | __FUNCTION__, dir->i_ino, tmp, qty, |
| 153 | ntohs(dbuf->blocks[tmp].pagehdr.magic)); |
| 154 | goto error; |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | SetPageChecked(page); |
| 159 | return; |
| 160 | |
| 161 | error: |
| 162 | SetPageChecked(page); |
| 163 | SetPageError(page); |
| 164 | |
| 165 | } /* end afs_dir_check_page() */ |
| 166 | |
| 167 | /*****************************************************************************/ |
| 168 | /* |
| 169 | * discard a page cached in the pagecache |
| 170 | */ |
| 171 | static inline void afs_dir_put_page(struct page *page) |
| 172 | { |
| 173 | kunmap(page); |
| 174 | page_cache_release(page); |
| 175 | |
| 176 | } /* end afs_dir_put_page() */ |
| 177 | |
| 178 | /*****************************************************************************/ |
| 179 | /* |
| 180 | * get a page into the pagecache |
| 181 | */ |
| 182 | static struct page *afs_dir_get_page(struct inode *dir, unsigned long index) |
| 183 | { |
| 184 | struct page *page; |
| 185 | |
| 186 | _enter("{%lu},%lu", dir->i_ino, index); |
| 187 | |
| 188 | page = read_cache_page(dir->i_mapping,index, |
| 189 | (filler_t *) dir->i_mapping->a_ops->readpage, |
| 190 | NULL); |
| 191 | if (!IS_ERR(page)) { |
| 192 | wait_on_page_locked(page); |
| 193 | kmap(page); |
| 194 | if (!PageUptodate(page)) |
| 195 | goto fail; |
| 196 | if (!PageChecked(page)) |
| 197 | afs_dir_check_page(dir, page); |
| 198 | if (PageError(page)) |
| 199 | goto fail; |
| 200 | } |
| 201 | return page; |
| 202 | |
| 203 | fail: |
| 204 | afs_dir_put_page(page); |
| 205 | return ERR_PTR(-EIO); |
| 206 | } /* end afs_dir_get_page() */ |
| 207 | |
| 208 | /*****************************************************************************/ |
| 209 | /* |
| 210 | * open an AFS directory file |
| 211 | */ |
| 212 | static int afs_dir_open(struct inode *inode, struct file *file) |
| 213 | { |
| 214 | _enter("{%lu}", inode->i_ino); |
| 215 | |
| 216 | BUG_ON(sizeof(union afs_dir_block) != 2048); |
| 217 | BUG_ON(sizeof(union afs_dirent) != 32); |
| 218 | |
| 219 | if (AFS_FS_I(inode)->flags & AFS_VNODE_DELETED) |
| 220 | return -ENOENT; |
| 221 | |
| 222 | _leave(" = 0"); |
| 223 | return 0; |
| 224 | |
| 225 | } /* end afs_dir_open() */ |
| 226 | |
| 227 | /*****************************************************************************/ |
| 228 | /* |
| 229 | * deal with one block in an AFS directory |
| 230 | */ |
| 231 | static int afs_dir_iterate_block(unsigned *fpos, |
| 232 | union afs_dir_block *block, |
| 233 | unsigned blkoff, |
| 234 | void *cookie, |
| 235 | filldir_t filldir) |
| 236 | { |
| 237 | union afs_dirent *dire; |
| 238 | unsigned offset, next, curr; |
| 239 | size_t nlen; |
| 240 | int tmp, ret; |
| 241 | |
| 242 | _enter("%u,%x,%p,,",*fpos,blkoff,block); |
| 243 | |
| 244 | curr = (*fpos - blkoff) / sizeof(union afs_dirent); |
| 245 | |
| 246 | /* walk through the block, an entry at a time */ |
| 247 | for (offset = AFS_DIRENT_PER_BLOCK - block->pagehdr.nentries; |
| 248 | offset < AFS_DIRENT_PER_BLOCK; |
| 249 | offset = next |
| 250 | ) { |
| 251 | next = offset + 1; |
| 252 | |
| 253 | /* skip entries marked unused in the bitmap */ |
| 254 | if (!(block->pagehdr.bitmap[offset / 8] & |
| 255 | (1 << (offset % 8)))) { |
| 256 | _debug("ENT[%Zu.%u]: unused\n", |
| 257 | blkoff / sizeof(union afs_dir_block), offset); |
| 258 | if (offset >= curr) |
| 259 | *fpos = blkoff + |
| 260 | next * sizeof(union afs_dirent); |
| 261 | continue; |
| 262 | } |
| 263 | |
| 264 | /* got a valid entry */ |
| 265 | dire = &block->dirents[offset]; |
| 266 | nlen = strnlen(dire->u.name, |
| 267 | sizeof(*block) - |
| 268 | offset * sizeof(union afs_dirent)); |
| 269 | |
| 270 | _debug("ENT[%Zu.%u]: %s %Zu \"%s\"\n", |
| 271 | blkoff / sizeof(union afs_dir_block), offset, |
| 272 | (offset < curr ? "skip" : "fill"), |
| 273 | nlen, dire->u.name); |
| 274 | |
| 275 | /* work out where the next possible entry is */ |
| 276 | for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_dirent)) { |
| 277 | if (next >= AFS_DIRENT_PER_BLOCK) { |
| 278 | _debug("ENT[%Zu.%u]:" |
| 279 | " %u travelled beyond end dir block" |
| 280 | " (len %u/%Zu)\n", |
| 281 | blkoff / sizeof(union afs_dir_block), |
| 282 | offset, next, tmp, nlen); |
| 283 | return -EIO; |
| 284 | } |
| 285 | if (!(block->pagehdr.bitmap[next / 8] & |
| 286 | (1 << (next % 8)))) { |
| 287 | _debug("ENT[%Zu.%u]:" |
| 288 | " %u unmarked extension (len %u/%Zu)\n", |
| 289 | blkoff / sizeof(union afs_dir_block), |
| 290 | offset, next, tmp, nlen); |
| 291 | return -EIO; |
| 292 | } |
| 293 | |
| 294 | _debug("ENT[%Zu.%u]: ext %u/%Zu\n", |
| 295 | blkoff / sizeof(union afs_dir_block), |
| 296 | next, tmp, nlen); |
| 297 | next++; |
| 298 | } |
| 299 | |
| 300 | /* skip if starts before the current position */ |
| 301 | if (offset < curr) |
| 302 | continue; |
| 303 | |
| 304 | /* found the next entry */ |
| 305 | ret = filldir(cookie, |
| 306 | dire->u.name, |
| 307 | nlen, |
| 308 | blkoff + offset * sizeof(union afs_dirent), |
| 309 | ntohl(dire->u.vnode), |
| 310 | filldir == afs_dir_lookup_filldir ? |
| 311 | ntohl(dire->u.unique) : DT_UNKNOWN); |
| 312 | if (ret < 0) { |
| 313 | _leave(" = 0 [full]"); |
| 314 | return 0; |
| 315 | } |
| 316 | |
| 317 | *fpos = blkoff + next * sizeof(union afs_dirent); |
| 318 | } |
| 319 | |
| 320 | _leave(" = 1 [more]"); |
| 321 | return 1; |
| 322 | } /* end afs_dir_iterate_block() */ |
| 323 | |
| 324 | /*****************************************************************************/ |
| 325 | /* |
| 326 | * read an AFS directory |
| 327 | */ |
| 328 | static int afs_dir_iterate(struct inode *dir, unsigned *fpos, void *cookie, |
| 329 | filldir_t filldir) |
| 330 | { |
| 331 | union afs_dir_block *dblock; |
| 332 | struct afs_dir_page *dbuf; |
| 333 | struct page *page; |
| 334 | unsigned blkoff, limit; |
| 335 | int ret; |
| 336 | |
| 337 | _enter("{%lu},%u,,", dir->i_ino, *fpos); |
| 338 | |
| 339 | if (AFS_FS_I(dir)->flags & AFS_VNODE_DELETED) { |
| 340 | _leave(" = -ESTALE"); |
| 341 | return -ESTALE; |
| 342 | } |
| 343 | |
| 344 | /* round the file position up to the next entry boundary */ |
| 345 | *fpos += sizeof(union afs_dirent) - 1; |
| 346 | *fpos &= ~(sizeof(union afs_dirent) - 1); |
| 347 | |
| 348 | /* walk through the blocks in sequence */ |
| 349 | ret = 0; |
| 350 | while (*fpos < dir->i_size) { |
| 351 | blkoff = *fpos & ~(sizeof(union afs_dir_block) - 1); |
| 352 | |
| 353 | /* fetch the appropriate page from the directory */ |
| 354 | page = afs_dir_get_page(dir, blkoff / PAGE_SIZE); |
| 355 | if (IS_ERR(page)) { |
| 356 | ret = PTR_ERR(page); |
| 357 | break; |
| 358 | } |
| 359 | |
| 360 | limit = blkoff & ~(PAGE_SIZE - 1); |
| 361 | |
| 362 | dbuf = page_address(page); |
| 363 | |
| 364 | /* deal with the individual blocks stashed on this page */ |
| 365 | do { |
| 366 | dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) / |
| 367 | sizeof(union afs_dir_block)]; |
| 368 | ret = afs_dir_iterate_block(fpos, dblock, blkoff, |
| 369 | cookie, filldir); |
| 370 | if (ret != 1) { |
| 371 | afs_dir_put_page(page); |
| 372 | goto out; |
| 373 | } |
| 374 | |
| 375 | blkoff += sizeof(union afs_dir_block); |
| 376 | |
| 377 | } while (*fpos < dir->i_size && blkoff < limit); |
| 378 | |
| 379 | afs_dir_put_page(page); |
| 380 | ret = 0; |
| 381 | } |
| 382 | |
| 383 | out: |
| 384 | _leave(" = %d", ret); |
| 385 | return ret; |
| 386 | } /* end afs_dir_iterate() */ |
| 387 | |
| 388 | /*****************************************************************************/ |
| 389 | /* |
| 390 | * read an AFS directory |
| 391 | */ |
| 392 | static int afs_dir_readdir(struct file *file, void *cookie, filldir_t filldir) |
| 393 | { |
| 394 | unsigned fpos; |
| 395 | int ret; |
| 396 | |
| 397 | _enter("{%Ld,{%lu}}", file->f_pos, file->f_dentry->d_inode->i_ino); |
| 398 | |
| 399 | fpos = file->f_pos; |
| 400 | ret = afs_dir_iterate(file->f_dentry->d_inode, &fpos, cookie, filldir); |
| 401 | file->f_pos = fpos; |
| 402 | |
| 403 | _leave(" = %d", ret); |
| 404 | return ret; |
| 405 | } /* end afs_dir_readdir() */ |
| 406 | |
| 407 | /*****************************************************************************/ |
| 408 | /* |
| 409 | * search the directory for a name |
| 410 | * - if afs_dir_iterate_block() spots this function, it'll pass the FID |
| 411 | * uniquifier through dtype |
| 412 | */ |
| 413 | static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen, |
| 414 | loff_t fpos, ino_t ino, unsigned dtype) |
| 415 | { |
| 416 | struct afs_dir_lookup_cookie *cookie = _cookie; |
| 417 | |
| 418 | _enter("{%s,%Zu},%s,%u,,%lu,%u", |
| 419 | cookie->name, cookie->nlen, name, nlen, ino, dtype); |
| 420 | |
| 421 | if (cookie->nlen != nlen || memcmp(cookie->name, name, nlen) != 0) { |
| 422 | _leave(" = 0 [no]"); |
| 423 | return 0; |
| 424 | } |
| 425 | |
| 426 | cookie->fid.vnode = ino; |
| 427 | cookie->fid.unique = dtype; |
| 428 | cookie->found = 1; |
| 429 | |
| 430 | _leave(" = -1 [found]"); |
| 431 | return -1; |
| 432 | } /* end afs_dir_lookup_filldir() */ |
| 433 | |
| 434 | /*****************************************************************************/ |
| 435 | /* |
| 436 | * look up an entry in a directory |
| 437 | */ |
| 438 | static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry, |
| 439 | struct nameidata *nd) |
| 440 | { |
| 441 | struct afs_dir_lookup_cookie cookie; |
| 442 | struct afs_super_info *as; |
| 443 | struct afs_vnode *vnode; |
| 444 | struct inode *inode; |
| 445 | unsigned fpos; |
| 446 | int ret; |
| 447 | |
| 448 | _enter("{%lu},%p{%s}", dir->i_ino, dentry, dentry->d_name.name); |
| 449 | |
| 450 | /* insanity checks first */ |
| 451 | BUG_ON(sizeof(union afs_dir_block) != 2048); |
| 452 | BUG_ON(sizeof(union afs_dirent) != 32); |
| 453 | |
| 454 | if (dentry->d_name.len > 255) { |
| 455 | _leave(" = -ENAMETOOLONG"); |
| 456 | return ERR_PTR(-ENAMETOOLONG); |
| 457 | } |
| 458 | |
| 459 | vnode = AFS_FS_I(dir); |
| 460 | if (vnode->flags & AFS_VNODE_DELETED) { |
| 461 | _leave(" = -ESTALE"); |
| 462 | return ERR_PTR(-ESTALE); |
| 463 | } |
| 464 | |
| 465 | as = dir->i_sb->s_fs_info; |
| 466 | |
| 467 | /* search the directory */ |
| 468 | cookie.name = dentry->d_name.name; |
| 469 | cookie.nlen = dentry->d_name.len; |
| 470 | cookie.fid.vid = as->volume->vid; |
| 471 | cookie.found = 0; |
| 472 | |
| 473 | fpos = 0; |
| 474 | ret = afs_dir_iterate(dir, &fpos, &cookie, afs_dir_lookup_filldir); |
| 475 | if (ret < 0) { |
| 476 | _leave(" = %d", ret); |
| 477 | return ERR_PTR(ret); |
| 478 | } |
| 479 | |
| 480 | ret = -ENOENT; |
| 481 | if (!cookie.found) { |
| 482 | _leave(" = %d", ret); |
| 483 | return ERR_PTR(ret); |
| 484 | } |
| 485 | |
| 486 | /* instantiate the dentry */ |
| 487 | ret = afs_iget(dir->i_sb, &cookie.fid, &inode); |
| 488 | if (ret < 0) { |
| 489 | _leave(" = %d", ret); |
| 490 | return ERR_PTR(ret); |
| 491 | } |
| 492 | |
| 493 | dentry->d_op = &afs_fs_dentry_operations; |
| 494 | dentry->d_fsdata = (void *) (unsigned long) vnode->status.version; |
| 495 | |
| 496 | d_add(dentry, inode); |
| 497 | _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%lu }", |
| 498 | cookie.fid.vnode, |
| 499 | cookie.fid.unique, |
| 500 | dentry->d_inode->i_ino, |
| 501 | dentry->d_inode->i_version); |
| 502 | |
| 503 | return NULL; |
| 504 | } /* end afs_dir_lookup() */ |
| 505 | |
| 506 | /*****************************************************************************/ |
| 507 | /* |
| 508 | * check that a dentry lookup hit has found a valid entry |
| 509 | * - NOTE! the hit can be a negative hit too, so we can't assume we have an |
| 510 | * inode |
| 511 | * (derived from nfs_lookup_revalidate) |
| 512 | */ |
| 513 | static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd) |
| 514 | { |
| 515 | struct afs_dir_lookup_cookie cookie; |
| 516 | struct dentry *parent; |
| 517 | struct inode *inode, *dir; |
| 518 | unsigned fpos; |
| 519 | int ret; |
| 520 | |
| 521 | _enter("{sb=%p n=%s},", dentry->d_sb, dentry->d_name.name); |
| 522 | |
| 523 | /* lock down the parent dentry so we can peer at it */ |
| 524 | parent = dget_parent(dentry->d_parent); |
| 525 | |
| 526 | dir = parent->d_inode; |
| 527 | inode = dentry->d_inode; |
| 528 | |
| 529 | /* handle a negative dentry */ |
| 530 | if (!inode) |
| 531 | goto out_bad; |
| 532 | |
| 533 | /* handle a bad inode */ |
| 534 | if (is_bad_inode(inode)) { |
| 535 | printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n", |
| 536 | dentry->d_parent->d_name.name, dentry->d_name.name); |
| 537 | goto out_bad; |
| 538 | } |
| 539 | |
| 540 | /* force a full look up if the parent directory changed since last the |
| 541 | * server was consulted |
| 542 | * - otherwise this inode must still exist, even if the inode details |
| 543 | * themselves have changed |
| 544 | */ |
| 545 | if (AFS_FS_I(dir)->flags & AFS_VNODE_CHANGED) |
| 546 | afs_vnode_fetch_status(AFS_FS_I(dir)); |
| 547 | |
| 548 | if (AFS_FS_I(dir)->flags & AFS_VNODE_DELETED) { |
| 549 | _debug("%s: parent dir deleted", dentry->d_name.name); |
| 550 | goto out_bad; |
| 551 | } |
| 552 | |
| 553 | if (AFS_FS_I(inode)->flags & AFS_VNODE_DELETED) { |
| 554 | _debug("%s: file already deleted", dentry->d_name.name); |
| 555 | goto out_bad; |
| 556 | } |
| 557 | |
| 558 | if ((unsigned long) dentry->d_fsdata != |
| 559 | (unsigned long) AFS_FS_I(dir)->status.version) { |
| 560 | _debug("%s: parent changed %lu -> %u", |
| 561 | dentry->d_name.name, |
| 562 | (unsigned long) dentry->d_fsdata, |
| 563 | (unsigned) AFS_FS_I(dir)->status.version); |
| 564 | |
| 565 | /* search the directory for this vnode */ |
| 566 | cookie.name = dentry->d_name.name; |
| 567 | cookie.nlen = dentry->d_name.len; |
| 568 | cookie.fid.vid = AFS_FS_I(inode)->volume->vid; |
| 569 | cookie.found = 0; |
| 570 | |
| 571 | fpos = 0; |
| 572 | ret = afs_dir_iterate(dir, &fpos, &cookie, |
| 573 | afs_dir_lookup_filldir); |
| 574 | if (ret < 0) { |
| 575 | _debug("failed to iterate dir %s: %d", |
| 576 | parent->d_name.name, ret); |
| 577 | goto out_bad; |
| 578 | } |
| 579 | |
| 580 | if (!cookie.found) { |
| 581 | _debug("%s: dirent not found", dentry->d_name.name); |
| 582 | goto not_found; |
| 583 | } |
| 584 | |
| 585 | /* if the vnode ID has changed, then the dirent points to a |
| 586 | * different file */ |
| 587 | if (cookie.fid.vnode != AFS_FS_I(inode)->fid.vnode) { |
| 588 | _debug("%s: dirent changed", dentry->d_name.name); |
| 589 | goto not_found; |
| 590 | } |
| 591 | |
| 592 | /* if the vnode ID uniqifier has changed, then the file has |
| 593 | * been deleted */ |
| 594 | if (cookie.fid.unique != AFS_FS_I(inode)->fid.unique) { |
| 595 | _debug("%s: file deleted (uq %u -> %u I:%lu)", |
| 596 | dentry->d_name.name, |
| 597 | cookie.fid.unique, |
| 598 | AFS_FS_I(inode)->fid.unique, |
| 599 | inode->i_version); |
| 600 | spin_lock(&AFS_FS_I(inode)->lock); |
| 601 | AFS_FS_I(inode)->flags |= AFS_VNODE_DELETED; |
| 602 | spin_unlock(&AFS_FS_I(inode)->lock); |
| 603 | invalidate_remote_inode(inode); |
| 604 | goto out_bad; |
| 605 | } |
| 606 | |
| 607 | dentry->d_fsdata = |
| 608 | (void *) (unsigned long) AFS_FS_I(dir)->status.version; |
| 609 | } |
| 610 | |
| 611 | out_valid: |
| 612 | dput(parent); |
| 613 | _leave(" = 1 [valid]"); |
| 614 | return 1; |
| 615 | |
| 616 | /* the dirent, if it exists, now points to a different vnode */ |
| 617 | not_found: |
| 618 | spin_lock(&dentry->d_lock); |
| 619 | dentry->d_flags |= DCACHE_NFSFS_RENAMED; |
| 620 | spin_unlock(&dentry->d_lock); |
| 621 | |
| 622 | out_bad: |
| 623 | if (inode) { |
| 624 | /* don't unhash if we have submounts */ |
| 625 | if (have_submounts(dentry)) |
| 626 | goto out_valid; |
| 627 | } |
| 628 | |
| 629 | shrink_dcache_parent(dentry); |
| 630 | |
| 631 | _debug("dropping dentry %s/%s", |
| 632 | dentry->d_parent->d_name.name, dentry->d_name.name); |
| 633 | d_drop(dentry); |
| 634 | |
| 635 | dput(parent); |
| 636 | |
| 637 | _leave(" = 0 [bad]"); |
| 638 | return 0; |
| 639 | } /* end afs_d_revalidate() */ |
| 640 | |
| 641 | /*****************************************************************************/ |
| 642 | /* |
| 643 | * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't |
| 644 | * sleep) |
| 645 | * - called from dput() when d_count is going to 0. |
| 646 | * - return 1 to request dentry be unhashed, 0 otherwise |
| 647 | */ |
| 648 | static int afs_d_delete(struct dentry *dentry) |
| 649 | { |
| 650 | _enter("%s", dentry->d_name.name); |
| 651 | |
| 652 | if (dentry->d_flags & DCACHE_NFSFS_RENAMED) |
| 653 | goto zap; |
| 654 | |
| 655 | if (dentry->d_inode) { |
| 656 | if (AFS_FS_I(dentry->d_inode)->flags & AFS_VNODE_DELETED) |
| 657 | goto zap; |
| 658 | } |
| 659 | |
| 660 | _leave(" = 0 [keep]"); |
| 661 | return 0; |
| 662 | |
| 663 | zap: |
| 664 | _leave(" = 1 [zap]"); |
| 665 | return 1; |
| 666 | } /* end afs_d_delete() */ |