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Diffstat (limited to 'fs/ubifs/orphan.c')
| -rw-r--r-- | fs/ubifs/orphan.c | 958 |
1 files changed, 958 insertions, 0 deletions
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c new file mode 100644 index 000000000000..3afeb9242c6a --- /dev/null +++ b/fs/ubifs/orphan.c | |||
| @@ -0,0 +1,958 @@ | |||
| 1 | /* | ||
| 2 | * This file is part of UBIFS. | ||
| 3 | * | ||
| 4 | * Copyright (C) 2006-2008 Nokia Corporation. | ||
| 5 | * | ||
| 6 | * This program is free software; you can redistribute it and/or modify it | ||
| 7 | * under the terms of the GNU General Public License version 2 as published by | ||
| 8 | * the Free Software Foundation. | ||
| 9 | * | ||
| 10 | * This program is distributed in the hope that it will be useful, but WITHOUT | ||
| 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
| 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
| 13 | * more details. | ||
| 14 | * | ||
| 15 | * You should have received a copy of the GNU General Public License along with | ||
| 16 | * this program; if not, write to the Free Software Foundation, Inc., 51 | ||
| 17 | * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 18 | * | ||
| 19 | * Author: Adrian Hunter | ||
| 20 | */ | ||
| 21 | |||
| 22 | #include "ubifs.h" | ||
| 23 | |||
| 24 | /* | ||
| 25 | * An orphan is an inode number whose inode node has been committed to the index | ||
| 26 | * with a link count of zero. That happens when an open file is deleted | ||
| 27 | * (unlinked) and then a commit is run. In the normal course of events the inode | ||
| 28 | * would be deleted when the file is closed. However in the case of an unclean | ||
| 29 | * unmount, orphans need to be accounted for. After an unclean unmount, the | ||
| 30 | * orphans' inodes must be deleted which means either scanning the entire index | ||
| 31 | * looking for them, or keeping a list on flash somewhere. This unit implements | ||
| 32 | * the latter approach. | ||
| 33 | * | ||
| 34 | * The orphan area is a fixed number of LEBs situated between the LPT area and | ||
| 35 | * the main area. The number of orphan area LEBs is specified when the file | ||
| 36 | * system is created. The minimum number is 1. The size of the orphan area | ||
| 37 | * should be so that it can hold the maximum number of orphans that are expected | ||
| 38 | * to ever exist at one time. | ||
| 39 | * | ||
| 40 | * The number of orphans that can fit in a LEB is: | ||
| 41 | * | ||
| 42 | * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64) | ||
| 43 | * | ||
| 44 | * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough. | ||
| 45 | * | ||
| 46 | * Orphans are accumulated in a rb-tree. When an inode's link count drops to | ||
| 47 | * zero, the inode number is added to the rb-tree. It is removed from the tree | ||
| 48 | * when the inode is deleted. Any new orphans that are in the orphan tree when | ||
| 49 | * the commit is run, are written to the orphan area in 1 or more orph nodes. | ||
| 50 | * If the orphan area is full, it is consolidated to make space. There is | ||
| 51 | * always enough space because validation prevents the user from creating more | ||
| 52 | * than the maximum number of orphans allowed. | ||
| 53 | */ | ||
| 54 | |||
| 55 | #ifdef CONFIG_UBIFS_FS_DEBUG | ||
| 56 | static int dbg_check_orphans(struct ubifs_info *c); | ||
| 57 | #else | ||
| 58 | #define dbg_check_orphans(c) 0 | ||
| 59 | #endif | ||
| 60 | |||
| 61 | /** | ||
| 62 | * ubifs_add_orphan - add an orphan. | ||
| 63 | * @c: UBIFS file-system description object | ||
| 64 | * @inum: orphan inode number | ||
| 65 | * | ||
| 66 | * Add an orphan. This function is called when an inodes link count drops to | ||
| 67 | * zero. | ||
| 68 | */ | ||
| 69 | int ubifs_add_orphan(struct ubifs_info *c, ino_t inum) | ||
| 70 | { | ||
| 71 | struct ubifs_orphan *orphan, *o; | ||
| 72 | struct rb_node **p, *parent = NULL; | ||
| 73 | |||
| 74 | orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS); | ||
| 75 | if (!orphan) | ||
| 76 | return -ENOMEM; | ||
| 77 | orphan->inum = inum; | ||
| 78 | orphan->new = 1; | ||
| 79 | |||
| 80 | spin_lock(&c->orphan_lock); | ||
| 81 | if (c->tot_orphans >= c->max_orphans) { | ||
| 82 | spin_unlock(&c->orphan_lock); | ||
| 83 | kfree(orphan); | ||
| 84 | return -ENFILE; | ||
| 85 | } | ||
| 86 | p = &c->orph_tree.rb_node; | ||
| 87 | while (*p) { | ||
| 88 | parent = *p; | ||
| 89 | o = rb_entry(parent, struct ubifs_orphan, rb); | ||
| 90 | if (inum < o->inum) | ||
| 91 | p = &(*p)->rb_left; | ||
| 92 | else if (inum > o->inum) | ||
| 93 | p = &(*p)->rb_right; | ||
| 94 | else { | ||
| 95 | dbg_err("orphaned twice"); | ||
| 96 | spin_unlock(&c->orphan_lock); | ||
| 97 | kfree(orphan); | ||
| 98 | return 0; | ||
| 99 | } | ||
| 100 | } | ||
| 101 | c->tot_orphans += 1; | ||
| 102 | c->new_orphans += 1; | ||
| 103 | rb_link_node(&orphan->rb, parent, p); | ||
| 104 | rb_insert_color(&orphan->rb, &c->orph_tree); | ||
| 105 | list_add_tail(&orphan->list, &c->orph_list); | ||
| 106 | list_add_tail(&orphan->new_list, &c->orph_new); | ||
| 107 | spin_unlock(&c->orphan_lock); | ||
| 108 | dbg_gen("ino %lu", inum); | ||
| 109 | return 0; | ||
| 110 | } | ||
| 111 | |||
| 112 | /** | ||
| 113 | * ubifs_delete_orphan - delete an orphan. | ||
| 114 | * @c: UBIFS file-system description object | ||
| 115 | * @inum: orphan inode number | ||
| 116 | * | ||
| 117 | * Delete an orphan. This function is called when an inode is deleted. | ||
| 118 | */ | ||
| 119 | void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum) | ||
| 120 | { | ||
| 121 | struct ubifs_orphan *o; | ||
| 122 | struct rb_node *p; | ||
| 123 | |||
| 124 | spin_lock(&c->orphan_lock); | ||
| 125 | p = c->orph_tree.rb_node; | ||
| 126 | while (p) { | ||
| 127 | o = rb_entry(p, struct ubifs_orphan, rb); | ||
| 128 | if (inum < o->inum) | ||
| 129 | p = p->rb_left; | ||
| 130 | else if (inum > o->inum) | ||
| 131 | p = p->rb_right; | ||
| 132 | else { | ||
| 133 | if (o->dnext) { | ||
| 134 | spin_unlock(&c->orphan_lock); | ||
| 135 | dbg_gen("deleted twice ino %lu", inum); | ||
| 136 | return; | ||
| 137 | } | ||
| 138 | if (o->cnext) { | ||
| 139 | o->dnext = c->orph_dnext; | ||
| 140 | c->orph_dnext = o; | ||
| 141 | spin_unlock(&c->orphan_lock); | ||
| 142 | dbg_gen("delete later ino %lu", inum); | ||
| 143 | return; | ||
| 144 | } | ||
| 145 | rb_erase(p, &c->orph_tree); | ||
| 146 | list_del(&o->list); | ||
| 147 | c->tot_orphans -= 1; | ||
| 148 | if (o->new) { | ||
| 149 | list_del(&o->new_list); | ||
| 150 | c->new_orphans -= 1; | ||
| 151 | } | ||
| 152 | spin_unlock(&c->orphan_lock); | ||
| 153 | kfree(o); | ||
| 154 | dbg_gen("inum %lu", inum); | ||
| 155 | return; | ||
| 156 | } | ||
| 157 | } | ||
| 158 | spin_unlock(&c->orphan_lock); | ||
| 159 | dbg_err("missing orphan ino %lu", inum); | ||
| 160 | dbg_dump_stack(); | ||
| 161 | } | ||
| 162 | |||
| 163 | /** | ||
| 164 | * ubifs_orphan_start_commit - start commit of orphans. | ||
| 165 | * @c: UBIFS file-system description object | ||
| 166 | * | ||
| 167 | * Start commit of orphans. | ||
| 168 | */ | ||
| 169 | int ubifs_orphan_start_commit(struct ubifs_info *c) | ||
| 170 | { | ||
| 171 | struct ubifs_orphan *orphan, **last; | ||
| 172 | |||
| 173 | spin_lock(&c->orphan_lock); | ||
| 174 | last = &c->orph_cnext; | ||
| 175 | list_for_each_entry(orphan, &c->orph_new, new_list) { | ||
| 176 | ubifs_assert(orphan->new); | ||
| 177 | orphan->new = 0; | ||
| 178 | *last = orphan; | ||
| 179 | last = &orphan->cnext; | ||
| 180 | } | ||
| 181 | *last = orphan->cnext; | ||
| 182 | c->cmt_orphans = c->new_orphans; | ||
| 183 | c->new_orphans = 0; | ||
| 184 | dbg_cmt("%d orphans to commit", c->cmt_orphans); | ||
| 185 | INIT_LIST_HEAD(&c->orph_new); | ||
| 186 | if (c->tot_orphans == 0) | ||
| 187 | c->no_orphs = 1; | ||
| 188 | else | ||
| 189 | c->no_orphs = 0; | ||
| 190 | spin_unlock(&c->orphan_lock); | ||
| 191 | return 0; | ||
| 192 | } | ||
| 193 | |||
| 194 | /** | ||
| 195 | * avail_orphs - calculate available space. | ||
| 196 | * @c: UBIFS file-system description object | ||
| 197 | * | ||
| 198 | * This function returns the number of orphans that can be written in the | ||
| 199 | * available space. | ||
| 200 | */ | ||
| 201 | static int avail_orphs(struct ubifs_info *c) | ||
| 202 | { | ||
| 203 | int avail_lebs, avail, gap; | ||
| 204 | |||
| 205 | avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1; | ||
| 206 | avail = avail_lebs * | ||
| 207 | ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); | ||
| 208 | gap = c->leb_size - c->ohead_offs; | ||
| 209 | if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64)) | ||
| 210 | avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); | ||
| 211 | return avail; | ||
| 212 | } | ||
| 213 | |||
| 214 | /** | ||
| 215 | * tot_avail_orphs - calculate total space. | ||
| 216 | * @c: UBIFS file-system description object | ||
| 217 | * | ||
| 218 | * This function returns the number of orphans that can be written in half | ||
| 219 | * the total space. That leaves half the space for adding new orphans. | ||
| 220 | */ | ||
| 221 | static int tot_avail_orphs(struct ubifs_info *c) | ||
| 222 | { | ||
| 223 | int avail_lebs, avail; | ||
| 224 | |||
| 225 | avail_lebs = c->orph_lebs; | ||
| 226 | avail = avail_lebs * | ||
| 227 | ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); | ||
| 228 | return avail / 2; | ||
| 229 | } | ||
| 230 | |||
| 231 | /** | ||
| 232 | * do_write_orph_node - write a node | ||
| 233 | * @c: UBIFS file-system description object | ||
| 234 | * @len: length of node | ||
| 235 | * @atomic: write atomically | ||
| 236 | * | ||
| 237 | * This function writes a node to the orphan head from the orphan buffer. If | ||
| 238 | * %atomic is not zero, then the write is done atomically. On success, %0 is | ||
| 239 | * returned, otherwise a negative error code is returned. | ||
| 240 | */ | ||
| 241 | static int do_write_orph_node(struct ubifs_info *c, int len, int atomic) | ||
| 242 | { | ||
| 243 | int err = 0; | ||
| 244 | |||
| 245 | if (atomic) { | ||
| 246 | ubifs_assert(c->ohead_offs == 0); | ||
| 247 | ubifs_prepare_node(c, c->orph_buf, len, 1); | ||
| 248 | len = ALIGN(len, c->min_io_size); | ||
| 249 | err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len, | ||
| 250 | UBI_SHORTTERM); | ||
| 251 | } else { | ||
| 252 | if (c->ohead_offs == 0) { | ||
| 253 | /* Ensure LEB has been unmapped */ | ||
| 254 | err = ubifs_leb_unmap(c, c->ohead_lnum); | ||
| 255 | if (err) | ||
| 256 | return err; | ||
| 257 | } | ||
| 258 | err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum, | ||
| 259 | c->ohead_offs, UBI_SHORTTERM); | ||
| 260 | } | ||
| 261 | return err; | ||
| 262 | } | ||
| 263 | |||
| 264 | /** | ||
| 265 | * write_orph_node - write an orph node | ||
| 266 | * @c: UBIFS file-system description object | ||
| 267 | * @atomic: write atomically | ||
| 268 | * | ||
| 269 | * This function builds an orph node from the cnext list and writes it to the | ||
| 270 | * orphan head. On success, %0 is returned, otherwise a negative error code | ||
| 271 | * is returned. | ||
| 272 | */ | ||
| 273 | static int write_orph_node(struct ubifs_info *c, int atomic) | ||
| 274 | { | ||
| 275 | struct ubifs_orphan *orphan, *cnext; | ||
| 276 | struct ubifs_orph_node *orph; | ||
| 277 | int gap, err, len, cnt, i; | ||
| 278 | |||
| 279 | ubifs_assert(c->cmt_orphans > 0); | ||
| 280 | gap = c->leb_size - c->ohead_offs; | ||
| 281 | if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) { | ||
| 282 | c->ohead_lnum += 1; | ||
| 283 | c->ohead_offs = 0; | ||
| 284 | gap = c->leb_size; | ||
| 285 | if (c->ohead_lnum > c->orph_last) { | ||
| 286 | /* | ||
| 287 | * We limit the number of orphans so that this should | ||
| 288 | * never happen. | ||
| 289 | */ | ||
| 290 | ubifs_err("out of space in orphan area"); | ||
| 291 | return -EINVAL; | ||
| 292 | } | ||
| 293 | } | ||
| 294 | cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); | ||
| 295 | if (cnt > c->cmt_orphans) | ||
| 296 | cnt = c->cmt_orphans; | ||
| 297 | len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64); | ||
| 298 | ubifs_assert(c->orph_buf); | ||
| 299 | orph = c->orph_buf; | ||
| 300 | orph->ch.node_type = UBIFS_ORPH_NODE; | ||
| 301 | spin_lock(&c->orphan_lock); | ||
| 302 | cnext = c->orph_cnext; | ||
| 303 | for (i = 0; i < cnt; i++) { | ||
| 304 | orphan = cnext; | ||
| 305 | orph->inos[i] = cpu_to_le64(orphan->inum); | ||
| 306 | cnext = orphan->cnext; | ||
| 307 | orphan->cnext = NULL; | ||
| 308 | } | ||
| 309 | c->orph_cnext = cnext; | ||
| 310 | c->cmt_orphans -= cnt; | ||
| 311 | spin_unlock(&c->orphan_lock); | ||
| 312 | if (c->cmt_orphans) | ||
| 313 | orph->cmt_no = cpu_to_le64(c->cmt_no + 1); | ||
| 314 | else | ||
| 315 | /* Mark the last node of the commit */ | ||
| 316 | orph->cmt_no = cpu_to_le64((c->cmt_no + 1) | (1ULL << 63)); | ||
| 317 | ubifs_assert(c->ohead_offs + len <= c->leb_size); | ||
| 318 | ubifs_assert(c->ohead_lnum >= c->orph_first); | ||
| 319 | ubifs_assert(c->ohead_lnum <= c->orph_last); | ||
| 320 | err = do_write_orph_node(c, len, atomic); | ||
| 321 | c->ohead_offs += ALIGN(len, c->min_io_size); | ||
| 322 | c->ohead_offs = ALIGN(c->ohead_offs, 8); | ||
| 323 | return err; | ||
| 324 | } | ||
| 325 | |||
| 326 | /** | ||
| 327 | * write_orph_nodes - write orph nodes until there are no more to commit | ||
| 328 | * @c: UBIFS file-system description object | ||
| 329 | * @atomic: write atomically | ||
| 330 | * | ||
| 331 | * This function writes orph nodes for all the orphans to commit. On success, | ||
| 332 | * %0 is returned, otherwise a negative error code is returned. | ||
| 333 | */ | ||
| 334 | static int write_orph_nodes(struct ubifs_info *c, int atomic) | ||
| 335 | { | ||
| 336 | int err; | ||
| 337 | |||
| 338 | while (c->cmt_orphans > 0) { | ||
| 339 | err = write_orph_node(c, atomic); | ||
| 340 | if (err) | ||
| 341 | return err; | ||
| 342 | } | ||
| 343 | if (atomic) { | ||
| 344 | int lnum; | ||
| 345 | |||
| 346 | /* Unmap any unused LEBs after consolidation */ | ||
| 347 | lnum = c->ohead_lnum + 1; | ||
| 348 | for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) { | ||
| 349 | err = ubifs_leb_unmap(c, lnum); | ||
| 350 | if (err) | ||
| 351 | return err; | ||
| 352 | } | ||
| 353 | } | ||
| 354 | return 0; | ||
| 355 | } | ||
| 356 | |||
| 357 | /** | ||
| 358 | * consolidate - consolidate the orphan area. | ||
| 359 | * @c: UBIFS file-system description object | ||
| 360 | * | ||
| 361 | * This function enables consolidation by putting all the orphans into the list | ||
| 362 | * to commit. The list is in the order that the orphans were added, and the | ||
| 363 | * LEBs are written atomically in order, so at no time can orphans be lost by | ||
| 364 | * an unclean unmount. | ||
| 365 | * | ||
| 366 | * This function returns %0 on success and a negative error code on failure. | ||
| 367 | */ | ||
| 368 | static int consolidate(struct ubifs_info *c) | ||
| 369 | { | ||
| 370 | int tot_avail = tot_avail_orphs(c), err = 0; | ||
| 371 | |||
| 372 | spin_lock(&c->orphan_lock); | ||
| 373 | dbg_cmt("there is space for %d orphans and there are %d", | ||
| 374 | tot_avail, c->tot_orphans); | ||
| 375 | if (c->tot_orphans - c->new_orphans <= tot_avail) { | ||
| 376 | struct ubifs_orphan *orphan, **last; | ||
| 377 | int cnt = 0; | ||
| 378 | |||
| 379 | /* Change the cnext list to include all non-new orphans */ | ||
| 380 | last = &c->orph_cnext; | ||
| 381 | list_for_each_entry(orphan, &c->orph_list, list) { | ||
| 382 | if (orphan->new) | ||
| 383 | continue; | ||
| 384 | *last = orphan; | ||
| 385 | last = &orphan->cnext; | ||
| 386 | cnt += 1; | ||
| 387 | } | ||
| 388 | *last = orphan->cnext; | ||
| 389 | ubifs_assert(cnt == c->tot_orphans - c->new_orphans); | ||
| 390 | c->cmt_orphans = cnt; | ||
| 391 | c->ohead_lnum = c->orph_first; | ||
| 392 | c->ohead_offs = 0; | ||
| 393 | } else { | ||
| 394 | /* | ||
| 395 | * We limit the number of orphans so that this should | ||
| 396 | * never happen. | ||
| 397 | */ | ||
| 398 | ubifs_err("out of space in orphan area"); | ||
| 399 | err = -EINVAL; | ||
| 400 | } | ||
| 401 | spin_unlock(&c->orphan_lock); | ||
| 402 | return err; | ||
| 403 | } | ||
| 404 | |||
| 405 | /** | ||
| 406 | * commit_orphans - commit orphans. | ||
| 407 | * @c: UBIFS file-system description object | ||
| 408 | * | ||
| 409 | * This function commits orphans to flash. On success, %0 is returned, | ||
| 410 | * otherwise a negative error code is returned. | ||
| 411 | */ | ||
| 412 | static int commit_orphans(struct ubifs_info *c) | ||
| 413 | { | ||
| 414 | int avail, atomic = 0, err; | ||
| 415 | |||
| 416 | ubifs_assert(c->cmt_orphans > 0); | ||
| 417 | avail = avail_orphs(c); | ||
| 418 | if (avail < c->cmt_orphans) { | ||
| 419 | /* Not enough space to write new orphans, so consolidate */ | ||
| 420 | err = consolidate(c); | ||
| 421 | if (err) | ||
| 422 | return err; | ||
| 423 | atomic = 1; | ||
| 424 | } | ||
| 425 | err = write_orph_nodes(c, atomic); | ||
| 426 | return err; | ||
| 427 | } | ||
| 428 | |||
| 429 | /** | ||
| 430 | * erase_deleted - erase the orphans marked for deletion. | ||
| 431 | * @c: UBIFS file-system description object | ||
| 432 | * | ||
| 433 | * During commit, the orphans being committed cannot be deleted, so they are | ||
| 434 | * marked for deletion and deleted by this function. Also, the recovery | ||
| 435 | * adds killed orphans to the deletion list, and therefore they are deleted | ||
| 436 | * here too. | ||
| 437 | */ | ||
| 438 | static void erase_deleted(struct ubifs_info *c) | ||
| 439 | { | ||
| 440 | struct ubifs_orphan *orphan, *dnext; | ||
| 441 | |||
| 442 | spin_lock(&c->orphan_lock); | ||
| 443 | dnext = c->orph_dnext; | ||
| 444 | while (dnext) { | ||
| 445 | orphan = dnext; | ||
| 446 | dnext = orphan->dnext; | ||
| 447 | ubifs_assert(!orphan->new); | ||
| 448 | rb_erase(&orphan->rb, &c->orph_tree); | ||
| 449 | list_del(&orphan->list); | ||
| 450 | c->tot_orphans -= 1; | ||
| 451 | dbg_gen("deleting orphan ino %lu", orphan->inum); | ||
| 452 | kfree(orphan); | ||
| 453 | } | ||
| 454 | c->orph_dnext = NULL; | ||
| 455 | spin_unlock(&c->orphan_lock); | ||
| 456 | } | ||
| 457 | |||
| 458 | /** | ||
| 459 | * ubifs_orphan_end_commit - end commit of orphans. | ||
| 460 | * @c: UBIFS file-system description object | ||
| 461 | * | ||
| 462 | * End commit of orphans. | ||
| 463 | */ | ||
| 464 | int ubifs_orphan_end_commit(struct ubifs_info *c) | ||
| 465 | { | ||
| 466 | int err; | ||
| 467 | |||
| 468 | if (c->cmt_orphans != 0) { | ||
| 469 | err = commit_orphans(c); | ||
| 470 | if (err) | ||
| 471 | return err; | ||
| 472 | } | ||
| 473 | erase_deleted(c); | ||
| 474 | err = dbg_check_orphans(c); | ||
| 475 | return err; | ||
| 476 | } | ||
| 477 | |||
| 478 | /** | ||
| 479 | * clear_orphans - erase all LEBs used for orphans. | ||
| 480 | * @c: UBIFS file-system description object | ||
| 481 | * | ||
| 482 | * If recovery is not required, then the orphans from the previous session | ||
| 483 | * are not needed. This function locates the LEBs used to record | ||
| 484 | * orphans, and un-maps them. | ||
| 485 | */ | ||
| 486 | static int clear_orphans(struct ubifs_info *c) | ||
| 487 | { | ||
| 488 | int lnum, err; | ||
| 489 | |||
| 490 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | ||
| 491 | err = ubifs_leb_unmap(c, lnum); | ||
| 492 | if (err) | ||
| 493 | return err; | ||
| 494 | } | ||
| 495 | c->ohead_lnum = c->orph_first; | ||
| 496 | c->ohead_offs = 0; | ||
| 497 | return 0; | ||
| 498 | } | ||
| 499 | |||
| 500 | /** | ||
| 501 | * insert_dead_orphan - insert an orphan. | ||
| 502 | * @c: UBIFS file-system description object | ||
| 503 | * @inum: orphan inode number | ||
| 504 | * | ||
| 505 | * This function is a helper to the 'do_kill_orphans()' function. The orphan | ||
| 506 | * must be kept until the next commit, so it is added to the rb-tree and the | ||
| 507 | * deletion list. | ||
| 508 | */ | ||
| 509 | static int insert_dead_orphan(struct ubifs_info *c, ino_t inum) | ||
| 510 | { | ||
| 511 | struct ubifs_orphan *orphan, *o; | ||
| 512 | struct rb_node **p, *parent = NULL; | ||
| 513 | |||
| 514 | orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL); | ||
| 515 | if (!orphan) | ||
| 516 | return -ENOMEM; | ||
| 517 | orphan->inum = inum; | ||
| 518 | |||
| 519 | p = &c->orph_tree.rb_node; | ||
| 520 | while (*p) { | ||
| 521 | parent = *p; | ||
| 522 | o = rb_entry(parent, struct ubifs_orphan, rb); | ||
| 523 | if (inum < o->inum) | ||
| 524 | p = &(*p)->rb_left; | ||
| 525 | else if (inum > o->inum) | ||
| 526 | p = &(*p)->rb_right; | ||
| 527 | else { | ||
| 528 | /* Already added - no problem */ | ||
| 529 | kfree(orphan); | ||
| 530 | return 0; | ||
| 531 | } | ||
| 532 | } | ||
| 533 | c->tot_orphans += 1; | ||
| 534 | rb_link_node(&orphan->rb, parent, p); | ||
| 535 | rb_insert_color(&orphan->rb, &c->orph_tree); | ||
| 536 | list_add_tail(&orphan->list, &c->orph_list); | ||
| 537 | orphan->dnext = c->orph_dnext; | ||
| 538 | c->orph_dnext = orphan; | ||
| 539 | dbg_mnt("ino %lu, new %d, tot %d", | ||
| 540 | inum, c->new_orphans, c->tot_orphans); | ||
| 541 | return 0; | ||
| 542 | } | ||
| 543 | |||
| 544 | /** | ||
| 545 | * do_kill_orphans - remove orphan inodes from the index. | ||
| 546 | * @c: UBIFS file-system description object | ||
| 547 | * @sleb: scanned LEB | ||
| 548 | * @last_cmt_no: cmt_no of last orph node read is passed and returned here | ||
| 549 | * @outofdate: whether the LEB is out of date is returned here | ||
| 550 | * @last_flagged: whether the end orph node is encountered | ||
| 551 | * | ||
| 552 | * This function is a helper to the 'kill_orphans()' function. It goes through | ||
| 553 | * every orphan node in a LEB and for every inode number recorded, removes | ||
| 554 | * all keys for that inode from the TNC. | ||
| 555 | */ | ||
| 556 | static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb, | ||
| 557 | unsigned long long *last_cmt_no, int *outofdate, | ||
| 558 | int *last_flagged) | ||
| 559 | { | ||
| 560 | struct ubifs_scan_node *snod; | ||
| 561 | struct ubifs_orph_node *orph; | ||
| 562 | unsigned long long cmt_no; | ||
| 563 | ino_t inum; | ||
| 564 | int i, n, err, first = 1; | ||
| 565 | |||
| 566 | list_for_each_entry(snod, &sleb->nodes, list) { | ||
| 567 | if (snod->type != UBIFS_ORPH_NODE) { | ||
| 568 | ubifs_err("invalid node type %d in orphan area at " | ||
| 569 | "%d:%d", snod->type, sleb->lnum, snod->offs); | ||
| 570 | dbg_dump_node(c, snod->node); | ||
| 571 | return -EINVAL; | ||
| 572 | } | ||
| 573 | |||
| 574 | orph = snod->node; | ||
| 575 | |||
| 576 | /* Check commit number */ | ||
| 577 | cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX; | ||
| 578 | /* | ||
| 579 | * The commit number on the master node may be less, because | ||
| 580 | * of a failed commit. If there are several failed commits in a | ||
| 581 | * row, the commit number written on orph nodes will continue to | ||
| 582 | * increase (because the commit number is adjusted here) even | ||
| 583 | * though the commit number on the master node stays the same | ||
| 584 | * because the master node has not been re-written. | ||
| 585 | */ | ||
| 586 | if (cmt_no > c->cmt_no) | ||
| 587 | c->cmt_no = cmt_no; | ||
| 588 | if (cmt_no < *last_cmt_no && *last_flagged) { | ||
| 589 | /* | ||
| 590 | * The last orph node had a higher commit number and was | ||
| 591 | * flagged as the last written for that commit number. | ||
| 592 | * That makes this orph node, out of date. | ||
| 593 | */ | ||
| 594 | if (!first) { | ||
| 595 | ubifs_err("out of order commit number %llu in " | ||
| 596 | "orphan node at %d:%d", | ||
| 597 | cmt_no, sleb->lnum, snod->offs); | ||
| 598 | dbg_dump_node(c, snod->node); | ||
| 599 | return -EINVAL; | ||
| 600 | } | ||
| 601 | dbg_rcvry("out of date LEB %d", sleb->lnum); | ||
| 602 | *outofdate = 1; | ||
| 603 | return 0; | ||
| 604 | } | ||
| 605 | |||
| 606 | if (first) | ||
| 607 | first = 0; | ||
| 608 | |||
| 609 | n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; | ||
| 610 | for (i = 0; i < n; i++) { | ||
| 611 | inum = le64_to_cpu(orph->inos[i]); | ||
| 612 | dbg_rcvry("deleting orphaned inode %lu", inum); | ||
| 613 | err = ubifs_tnc_remove_ino(c, inum); | ||
| 614 | if (err) | ||
| 615 | return err; | ||
| 616 | err = insert_dead_orphan(c, inum); | ||
| 617 | if (err) | ||
| 618 | return err; | ||
| 619 | } | ||
| 620 | |||
| 621 | *last_cmt_no = cmt_no; | ||
| 622 | if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) { | ||
| 623 | dbg_rcvry("last orph node for commit %llu at %d:%d", | ||
| 624 | cmt_no, sleb->lnum, snod->offs); | ||
| 625 | *last_flagged = 1; | ||
| 626 | } else | ||
| 627 | *last_flagged = 0; | ||
| 628 | } | ||
| 629 | |||
| 630 | return 0; | ||
| 631 | } | ||
| 632 | |||
| 633 | /** | ||
| 634 | * kill_orphans - remove all orphan inodes from the index. | ||
| 635 | * @c: UBIFS file-system description object | ||
| 636 | * | ||
| 637 | * If recovery is required, then orphan inodes recorded during the previous | ||
| 638 | * session (which ended with an unclean unmount) must be deleted from the index. | ||
| 639 | * This is done by updating the TNC, but since the index is not updated until | ||
| 640 | * the next commit, the LEBs where the orphan information is recorded are not | ||
| 641 | * erased until the next commit. | ||
| 642 | */ | ||
| 643 | static int kill_orphans(struct ubifs_info *c) | ||
| 644 | { | ||
| 645 | unsigned long long last_cmt_no = 0; | ||
| 646 | int lnum, err = 0, outofdate = 0, last_flagged = 0; | ||
| 647 | |||
| 648 | c->ohead_lnum = c->orph_first; | ||
| 649 | c->ohead_offs = 0; | ||
| 650 | /* Check no-orphans flag and skip this if no orphans */ | ||
| 651 | if (c->no_orphs) { | ||
| 652 | dbg_rcvry("no orphans"); | ||
| 653 | return 0; | ||
| 654 | } | ||
| 655 | /* | ||
| 656 | * Orph nodes always start at c->orph_first and are written to each | ||
| 657 | * successive LEB in turn. Generally unused LEBs will have been unmapped | ||
| 658 | * but may contain out of date orph nodes if the unmap didn't go | ||
| 659 | * through. In addition, the last orph node written for each commit is | ||
| 660 | * marked (top bit of orph->cmt_no is set to 1). It is possible that | ||
| 661 | * there are orph nodes from the next commit (i.e. the commit did not | ||
| 662 | * complete successfully). In that case, no orphans will have been lost | ||
| 663 | * due to the way that orphans are written, and any orphans added will | ||
| 664 | * be valid orphans anyway and so can be deleted. | ||
| 665 | */ | ||
| 666 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | ||
| 667 | struct ubifs_scan_leb *sleb; | ||
| 668 | |||
| 669 | dbg_rcvry("LEB %d", lnum); | ||
| 670 | sleb = ubifs_scan(c, lnum, 0, c->sbuf); | ||
| 671 | if (IS_ERR(sleb)) { | ||
| 672 | sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0); | ||
| 673 | if (IS_ERR(sleb)) { | ||
| 674 | err = PTR_ERR(sleb); | ||
| 675 | break; | ||
| 676 | } | ||
| 677 | } | ||
| 678 | err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate, | ||
| 679 | &last_flagged); | ||
| 680 | if (err || outofdate) { | ||
| 681 | ubifs_scan_destroy(sleb); | ||
| 682 | break; | ||
| 683 | } | ||
| 684 | if (sleb->endpt) { | ||
| 685 | c->ohead_lnum = lnum; | ||
| 686 | c->ohead_offs = sleb->endpt; | ||
| 687 | } | ||
| 688 | ubifs_scan_destroy(sleb); | ||
| 689 | } | ||
| 690 | return err; | ||
| 691 | } | ||
| 692 | |||
| 693 | /** | ||
| 694 | * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them. | ||
| 695 | * @c: UBIFS file-system description object | ||
| 696 | * @unclean: indicates recovery from unclean unmount | ||
| 697 | * @read_only: indicates read only mount | ||
| 698 | * | ||
| 699 | * This function is called when mounting to erase orphans from the previous | ||
| 700 | * session. If UBIFS was not unmounted cleanly, then the inodes recorded as | ||
| 701 | * orphans are deleted. | ||
| 702 | */ | ||
| 703 | int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only) | ||
| 704 | { | ||
| 705 | int err = 0; | ||
| 706 | |||
| 707 | c->max_orphans = tot_avail_orphs(c); | ||
| 708 | |||
| 709 | if (!read_only) { | ||
| 710 | c->orph_buf = vmalloc(c->leb_size); | ||
| 711 | if (!c->orph_buf) | ||
| 712 | return -ENOMEM; | ||
| 713 | } | ||
| 714 | |||
| 715 | if (unclean) | ||
| 716 | err = kill_orphans(c); | ||
| 717 | else if (!read_only) | ||
| 718 | err = clear_orphans(c); | ||
| 719 | |||
| 720 | return err; | ||
| 721 | } | ||
| 722 | |||
| 723 | #ifdef CONFIG_UBIFS_FS_DEBUG | ||
| 724 | |||
| 725 | struct check_orphan { | ||
| 726 | struct rb_node rb; | ||
| 727 | ino_t inum; | ||
| 728 | }; | ||
| 729 | |||
| 730 | struct check_info { | ||
| 731 | unsigned long last_ino; | ||
| 732 | unsigned long tot_inos; | ||
| 733 | unsigned long missing; | ||
| 734 | unsigned long long leaf_cnt; | ||
| 735 | struct ubifs_ino_node *node; | ||
| 736 | struct rb_root root; | ||
| 737 | }; | ||
| 738 | |||
| 739 | static int dbg_find_orphan(struct ubifs_info *c, ino_t inum) | ||
| 740 | { | ||
| 741 | struct ubifs_orphan *o; | ||
| 742 | struct rb_node *p; | ||
| 743 | |||
| 744 | spin_lock(&c->orphan_lock); | ||
| 745 | p = c->orph_tree.rb_node; | ||
| 746 | while (p) { | ||
| 747 | o = rb_entry(p, struct ubifs_orphan, rb); | ||
| 748 | if (inum < o->inum) | ||
| 749 | p = p->rb_left; | ||
| 750 | else if (inum > o->inum) | ||
| 751 | p = p->rb_right; | ||
| 752 | else { | ||
| 753 | spin_unlock(&c->orphan_lock); | ||
| 754 | return 1; | ||
| 755 | } | ||
| 756 | } | ||
| 757 | spin_unlock(&c->orphan_lock); | ||
| 758 | return 0; | ||
| 759 | } | ||
| 760 | |||
| 761 | static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum) | ||
| 762 | { | ||
| 763 | struct check_orphan *orphan, *o; | ||
| 764 | struct rb_node **p, *parent = NULL; | ||
| 765 | |||
| 766 | orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS); | ||
| 767 | if (!orphan) | ||
| 768 | return -ENOMEM; | ||
| 769 | orphan->inum = inum; | ||
| 770 | |||
| 771 | p = &root->rb_node; | ||
| 772 | while (*p) { | ||
| 773 | parent = *p; | ||
| 774 | o = rb_entry(parent, struct check_orphan, rb); | ||
| 775 | if (inum < o->inum) | ||
| 776 | p = &(*p)->rb_left; | ||
| 777 | else if (inum > o->inum) | ||
| 778 | p = &(*p)->rb_right; | ||
| 779 | else { | ||
| 780 | kfree(orphan); | ||
| 781 | return 0; | ||
| 782 | } | ||
| 783 | } | ||
| 784 | rb_link_node(&orphan->rb, parent, p); | ||
| 785 | rb_insert_color(&orphan->rb, root); | ||
| 786 | return 0; | ||
| 787 | } | ||
| 788 | |||
| 789 | static int dbg_find_check_orphan(struct rb_root *root, ino_t inum) | ||
| 790 | { | ||
| 791 | struct check_orphan *o; | ||
| 792 | struct rb_node *p; | ||
| 793 | |||
| 794 | p = root->rb_node; | ||
| 795 | while (p) { | ||
| 796 | o = rb_entry(p, struct check_orphan, rb); | ||
| 797 | if (inum < o->inum) | ||
| 798 | p = p->rb_left; | ||
| 799 | else if (inum > o->inum) | ||
| 800 | p = p->rb_right; | ||
| 801 | else | ||
| 802 | return 1; | ||
| 803 | } | ||
| 804 | return 0; | ||
| 805 | } | ||
| 806 | |||
| 807 | static void dbg_free_check_tree(struct rb_root *root) | ||
| 808 | { | ||
| 809 | struct rb_node *this = root->rb_node; | ||
| 810 | struct check_orphan *o; | ||
| 811 | |||
| 812 | while (this) { | ||
| 813 | if (this->rb_left) { | ||
| 814 | this = this->rb_left; | ||
| 815 | continue; | ||
| 816 | } else if (this->rb_right) { | ||
| 817 | this = this->rb_right; | ||
| 818 | continue; | ||
| 819 | } | ||
| 820 | o = rb_entry(this, struct check_orphan, rb); | ||
| 821 | this = rb_parent(this); | ||
| 822 | if (this) { | ||
| 823 | if (this->rb_left == &o->rb) | ||
| 824 | this->rb_left = NULL; | ||
| 825 | else | ||
| 826 | this->rb_right = NULL; | ||
| 827 | } | ||
| 828 | kfree(o); | ||
| 829 | } | ||
| 830 | } | ||
| 831 | |||
| 832 | static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr, | ||
| 833 | void *priv) | ||
| 834 | { | ||
| 835 | struct check_info *ci = priv; | ||
| 836 | ino_t inum; | ||
| 837 | int err; | ||
| 838 | |||
| 839 | inum = key_inum(c, &zbr->key); | ||
| 840 | if (inum != ci->last_ino) { | ||
| 841 | /* Lowest node type is the inode node, so it comes first */ | ||
| 842 | if (key_type(c, &zbr->key) != UBIFS_INO_KEY) | ||
| 843 | ubifs_err("found orphan node ino %lu, type %d", inum, | ||
| 844 | key_type(c, &zbr->key)); | ||
| 845 | ci->last_ino = inum; | ||
| 846 | ci->tot_inos += 1; | ||
| 847 | err = ubifs_tnc_read_node(c, zbr, ci->node); | ||
| 848 | if (err) { | ||
| 849 | ubifs_err("node read failed, error %d", err); | ||
| 850 | return err; | ||
| 851 | } | ||
| 852 | if (ci->node->nlink == 0) | ||
| 853 | /* Must be recorded as an orphan */ | ||
| 854 | if (!dbg_find_check_orphan(&ci->root, inum) && | ||
| 855 | !dbg_find_orphan(c, inum)) { | ||
| 856 | ubifs_err("missing orphan, ino %lu", inum); | ||
| 857 | ci->missing += 1; | ||
| 858 | } | ||
| 859 | } | ||
| 860 | ci->leaf_cnt += 1; | ||
| 861 | return 0; | ||
| 862 | } | ||
| 863 | |||
| 864 | static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb) | ||
| 865 | { | ||
| 866 | struct ubifs_scan_node *snod; | ||
| 867 | struct ubifs_orph_node *orph; | ||
| 868 | ino_t inum; | ||
| 869 | int i, n, err; | ||
| 870 | |||
| 871 | list_for_each_entry(snod, &sleb->nodes, list) { | ||
| 872 | cond_resched(); | ||
| 873 | if (snod->type != UBIFS_ORPH_NODE) | ||
| 874 | continue; | ||
| 875 | orph = snod->node; | ||
| 876 | n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; | ||
| 877 | for (i = 0; i < n; i++) { | ||
| 878 | inum = le64_to_cpu(orph->inos[i]); | ||
| 879 | err = dbg_ins_check_orphan(&ci->root, inum); | ||
| 880 | if (err) | ||
| 881 | return err; | ||
| 882 | } | ||
| 883 | } | ||
| 884 | return 0; | ||
| 885 | } | ||
| 886 | |||
| 887 | static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci) | ||
| 888 | { | ||
| 889 | int lnum, err = 0; | ||
| 890 | |||
| 891 | /* Check no-orphans flag and skip this if no orphans */ | ||
| 892 | if (c->no_orphs) | ||
| 893 | return 0; | ||
| 894 | |||
| 895 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | ||
| 896 | struct ubifs_scan_leb *sleb; | ||
| 897 | |||
| 898 | sleb = ubifs_scan(c, lnum, 0, c->dbg_buf); | ||
| 899 | if (IS_ERR(sleb)) { | ||
| 900 | err = PTR_ERR(sleb); | ||
| 901 | break; | ||
| 902 | } | ||
| 903 | |||
| 904 | err = dbg_read_orphans(ci, sleb); | ||
| 905 | ubifs_scan_destroy(sleb); | ||
| 906 | if (err) | ||
| 907 | break; | ||
| 908 | } | ||
| 909 | |||
| 910 | return err; | ||
| 911 | } | ||
| 912 | |||
| 913 | static int dbg_check_orphans(struct ubifs_info *c) | ||
| 914 | { | ||
| 915 | struct check_info ci; | ||
| 916 | int err; | ||
| 917 | |||
| 918 | if (!(ubifs_chk_flags & UBIFS_CHK_ORPH)) | ||
| 919 | return 0; | ||
| 920 | |||
| 921 | ci.last_ino = 0; | ||
| 922 | ci.tot_inos = 0; | ||
| 923 | ci.missing = 0; | ||
| 924 | ci.leaf_cnt = 0; | ||
| 925 | ci.root = RB_ROOT; | ||
| 926 | ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); | ||
| 927 | if (!ci.node) { | ||
| 928 | ubifs_err("out of memory"); | ||
| 929 | return -ENOMEM; | ||
| 930 | } | ||
| 931 | |||
| 932 | err = dbg_scan_orphans(c, &ci); | ||
| 933 | if (err) | ||
| 934 | goto out; | ||
| 935 | |||
| 936 | err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci); | ||
| 937 | if (err) { | ||
| 938 | ubifs_err("cannot scan TNC, error %d", err); | ||
| 939 | goto out; | ||
| 940 | } | ||
| 941 | |||
| 942 | if (ci.missing) { | ||
| 943 | ubifs_err("%lu missing orphan(s)", ci.missing); | ||
| 944 | err = -EINVAL; | ||
| 945 | goto out; | ||
| 946 | } | ||
| 947 | |||
| 948 | dbg_cmt("last inode number is %lu", ci.last_ino); | ||
| 949 | dbg_cmt("total number of inodes is %lu", ci.tot_inos); | ||
| 950 | dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt); | ||
| 951 | |||
| 952 | out: | ||
| 953 | dbg_free_check_tree(&ci.root); | ||
| 954 | kfree(ci.node); | ||
| 955 | return err; | ||
| 956 | } | ||
| 957 | |||
| 958 | #endif /* CONFIG_UBIFS_FS_DEBUG */ | ||
