root/fs/nilfs2/bmap.c

DEFINITIONS

1. nilfs_bmap_get_dat
2. nilfs_bmap_convert_error
3. nilfs_bmap_lookup_at_level
4. nilfs_bmap_lookup_contig
5. nilfs_bmap_do_insert
6. nilfs_bmap_insert
7. nilfs_bmap_do_delete
8. nilfs_bmap_seek_key
9. nilfs_bmap_last_key
10. nilfs_bmap_delete
11. nilfs_bmap_do_truncate
12. nilfs_bmap_truncate
13. nilfs_bmap_clear
14. nilfs_bmap_propagate
15. nilfs_bmap_lookup_dirty_buffers
16. nilfs_bmap_assign
17. nilfs_bmap_mark
18. nilfs_bmap_test_and_clear_dirty
19. nilfs_bmap_data_get_key
20. nilfs_bmap_find_target_seq
21. nilfs_bmap_find_target_in_group
22. nilfs_bmap_read
23. nilfs_bmap_write
24. nilfs_bmap_init_gc
25. nilfs_bmap_save
26. nilfs_bmap_restore

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * bmap.c - NILFS block mapping.
   4  *
   5  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
   6  *
   7  * Written by Koji Sato.
   8  */
   9 
  10 #include <linux/fs.h>
  11 #include <linux/string.h>
  12 #include <linux/errno.h>
  13 #include "nilfs.h"
  14 #include "bmap.h"
  15 #include "btree.h"
  16 #include "direct.h"
  17 #include "btnode.h"
  18 #include "mdt.h"
  19 #include "dat.h"
  20 #include "alloc.h"
  21 
  22 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)
  23 {
  24         struct the_nilfs *nilfs = bmap->b_inode->i_sb->s_fs_info;
  25 
  26         return nilfs->ns_dat;
  27 }
  28 
  29 static int nilfs_bmap_convert_error(struct nilfs_bmap *bmap,
  30                                      const char *fname, int err)
  31 {
  32         struct inode *inode = bmap->b_inode;
  33 
  34         if (err == -EINVAL) {
  35                 __nilfs_error(inode->i_sb, fname,
  36                               "broken bmap (inode number=%lu)", inode->i_ino);
  37                 err = -EIO;
  38         }
  39         return err;
  40 }
  41 
  42 /**
  43  * nilfs_bmap_lookup_at_level - find a data block or node block
  44  * @bmap: bmap
  45  * @key: key
  46  * @level: level
  47  * @ptrp: place to store the value associated to @key
  48  *
  49  * Description: nilfs_bmap_lookup_at_level() finds a record whose key
  50  * matches @key in the block at @level of the bmap.
  51  *
  52  * Return Value: On success, 0 is returned and the record associated with @key
  53  * is stored in the place pointed by @ptrp. On error, one of the following
  54  * negative error codes is returned.
  55  *
  56  * %-EIO - I/O error.
  57  *
  58  * %-ENOMEM - Insufficient amount of memory available.
  59  *
  60  * %-ENOENT - A record associated with @key does not exist.
  61  */
  62 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level,
  63                                __u64 *ptrp)
  64 {
  65         sector_t blocknr;
  66         int ret;
  67 
  68         down_read(&bmap->b_sem);
  69         ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp);
  70         if (ret < 0) {
  71                 ret = nilfs_bmap_convert_error(bmap, __func__, ret);
  72                 goto out;
  73         }
  74         if (NILFS_BMAP_USE_VBN(bmap)) {
  75                 ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp,
  76                                           &blocknr);
  77                 if (!ret)
  78                         *ptrp = blocknr;
  79         }
  80 
  81  out:
  82         up_read(&bmap->b_sem);
  83         return ret;
  84 }
  85 
  86 int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,
  87                              unsigned int maxblocks)
  88 {
  89         int ret;
  90 
  91         down_read(&bmap->b_sem);
  92         ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);
  93         up_read(&bmap->b_sem);
  94 
  95         return nilfs_bmap_convert_error(bmap, __func__, ret);
  96 }
  97 
  98 static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
  99 {
 100         __u64 keys[NILFS_BMAP_SMALL_HIGH + 1];
 101         __u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1];
 102         int ret, n;
 103 
 104         if (bmap->b_ops->bop_check_insert != NULL) {
 105                 ret = bmap->b_ops->bop_check_insert(bmap, key);
 106                 if (ret > 0) {
 107                         n = bmap->b_ops->bop_gather_data(
 108                                 bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1);
 109                         if (n < 0)
 110                                 return n;
 111                         ret = nilfs_btree_convert_and_insert(
 112                                 bmap, key, ptr, keys, ptrs, n);
 113                         if (ret == 0)
 114                                 bmap->b_u.u_flags |= NILFS_BMAP_LARGE;
 115 
 116                         return ret;
 117                 } else if (ret < 0)
 118                         return ret;
 119         }
 120 
 121         return bmap->b_ops->bop_insert(bmap, key, ptr);
 122 }
 123 
 124 /**
 125  * nilfs_bmap_insert - insert a new key-record pair into a bmap
 126  * @bmap: bmap
 127  * @key: key
 128  * @rec: record
 129  *
 130  * Description: nilfs_bmap_insert() inserts the new key-record pair specified
 131  * by @key and @rec into @bmap.
 132  *
 133  * Return Value: On success, 0 is returned. On error, one of the following
 134  * negative error codes is returned.
 135  *
 136  * %-EIO - I/O error.
 137  *
 138  * %-ENOMEM - Insufficient amount of memory available.
 139  *
 140  * %-EEXIST - A record associated with @key already exist.
 141  */
 142 int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec)
 143 {
 144         int ret;
 145 
 146         down_write(&bmap->b_sem);
 147         ret = nilfs_bmap_do_insert(bmap, key, rec);
 148         up_write(&bmap->b_sem);
 149 
 150         return nilfs_bmap_convert_error(bmap, __func__, ret);
 151 }
 152 
 153 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key)
 154 {
 155         __u64 keys[NILFS_BMAP_LARGE_LOW + 1];
 156         __u64 ptrs[NILFS_BMAP_LARGE_LOW + 1];
 157         int ret, n;
 158 
 159         if (bmap->b_ops->bop_check_delete != NULL) {
 160                 ret = bmap->b_ops->bop_check_delete(bmap, key);
 161                 if (ret > 0) {
 162                         n = bmap->b_ops->bop_gather_data(
 163                                 bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1);
 164                         if (n < 0)
 165                                 return n;
 166                         ret = nilfs_direct_delete_and_convert(
 167                                 bmap, key, keys, ptrs, n);
 168                         if (ret == 0)
 169                                 bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE;
 170 
 171                         return ret;
 172                 } else if (ret < 0)
 173                         return ret;
 174         }
 175 
 176         return bmap->b_ops->bop_delete(bmap, key);
 177 }
 178 
 179 /**
 180  * nilfs_bmap_seek_key - seek a valid entry and return its key
 181  * @bmap: bmap struct
 182  * @start: start key number
 183  * @keyp: place to store valid key
 184  *
 185  * Description: nilfs_bmap_seek_key() seeks a valid key on @bmap
 186  * starting from @start, and stores it to @keyp if found.
 187  *
 188  * Return Value: On success, 0 is returned. On error, one of the following
 189  * negative error codes is returned.
 190  *
 191  * %-EIO - I/O error.
 192  *
 193  * %-ENOMEM - Insufficient amount of memory available.
 194  *
 195  * %-ENOENT - No valid entry was found
 196  */
 197 int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp)
 198 {
 199         int ret;
 200 
 201         down_read(&bmap->b_sem);
 202         ret = bmap->b_ops->bop_seek_key(bmap, start, keyp);
 203         up_read(&bmap->b_sem);
 204 
 205         if (ret < 0)
 206                 ret = nilfs_bmap_convert_error(bmap, __func__, ret);
 207         return ret;
 208 }
 209 
 210 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp)
 211 {
 212         int ret;
 213 
 214         down_read(&bmap->b_sem);
 215         ret = bmap->b_ops->bop_last_key(bmap, keyp);
 216         up_read(&bmap->b_sem);
 217 
 218         if (ret < 0)
 219                 ret = nilfs_bmap_convert_error(bmap, __func__, ret);
 220         return ret;
 221 }
 222 
 223 /**
 224  * nilfs_bmap_delete - delete a key-record pair from a bmap
 225  * @bmap: bmap
 226  * @key: key
 227  *
 228  * Description: nilfs_bmap_delete() deletes the key-record pair specified by
 229  * @key from @bmap.
 230  *
 231  * Return Value: On success, 0 is returned. On error, one of the following
 232  * negative error codes is returned.
 233  *
 234  * %-EIO - I/O error.
 235  *
 236  * %-ENOMEM - Insufficient amount of memory available.
 237  *
 238  * %-ENOENT - A record associated with @key does not exist.
 239  */
 240 int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key)
 241 {
 242         int ret;
 243 
 244         down_write(&bmap->b_sem);
 245         ret = nilfs_bmap_do_delete(bmap, key);
 246         up_write(&bmap->b_sem);
 247 
 248         return nilfs_bmap_convert_error(bmap, __func__, ret);
 249 }
 250 
 251 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, __u64 key)
 252 {
 253         __u64 lastkey;
 254         int ret;
 255 
 256         ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
 257         if (ret < 0) {
 258                 if (ret == -ENOENT)
 259                         ret = 0;
 260                 return ret;
 261         }
 262 
 263         while (key <= lastkey) {
 264                 ret = nilfs_bmap_do_delete(bmap, lastkey);
 265                 if (ret < 0)
 266                         return ret;
 267                 ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
 268                 if (ret < 0) {
 269                         if (ret == -ENOENT)
 270                                 ret = 0;
 271                         return ret;
 272                 }
 273         }
 274         return 0;
 275 }
 276 
 277 /**
 278  * nilfs_bmap_truncate - truncate a bmap to a specified key
 279  * @bmap: bmap
 280  * @key: key
 281  *
 282  * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are
 283  * greater than or equal to @key from @bmap.
 284  *
 285  * Return Value: On success, 0 is returned. On error, one of the following
 286  * negative error codes is returned.
 287  *
 288  * %-EIO - I/O error.
 289  *
 290  * %-ENOMEM - Insufficient amount of memory available.
 291  */
 292 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key)
 293 {
 294         int ret;
 295 
 296         down_write(&bmap->b_sem);
 297         ret = nilfs_bmap_do_truncate(bmap, key);
 298         up_write(&bmap->b_sem);
 299 
 300         return nilfs_bmap_convert_error(bmap, __func__, ret);
 301 }
 302 
 303 /**
 304  * nilfs_bmap_clear - free resources a bmap holds
 305  * @bmap: bmap
 306  *
 307  * Description: nilfs_bmap_clear() frees resources associated with @bmap.
 308  */
 309 void nilfs_bmap_clear(struct nilfs_bmap *bmap)
 310 {
 311         down_write(&bmap->b_sem);
 312         if (bmap->b_ops->bop_clear != NULL)
 313                 bmap->b_ops->bop_clear(bmap);
 314         up_write(&bmap->b_sem);
 315 }
 316 
 317 /**
 318  * nilfs_bmap_propagate - propagate dirty state
 319  * @bmap: bmap
 320  * @bh: buffer head
 321  *
 322  * Description: nilfs_bmap_propagate() marks the buffers that directly or
 323  * indirectly refer to the block specified by @bh dirty.
 324  *
 325  * Return Value: On success, 0 is returned. On error, one of the following
 326  * negative error codes is returned.
 327  *
 328  * %-EIO - I/O error.
 329  *
 330  * %-ENOMEM - Insufficient amount of memory available.
 331  */
 332 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh)
 333 {
 334         int ret;
 335 
 336         down_write(&bmap->b_sem);
 337         ret = bmap->b_ops->bop_propagate(bmap, bh);
 338         up_write(&bmap->b_sem);
 339 
 340         return nilfs_bmap_convert_error(bmap, __func__, ret);
 341 }
 342 
 343 /**
 344  * nilfs_bmap_lookup_dirty_buffers -
 345  * @bmap: bmap
 346  * @listp: pointer to buffer head list
 347  */
 348 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap,
 349                                      struct list_head *listp)
 350 {
 351         if (bmap->b_ops->bop_lookup_dirty_buffers != NULL)
 352                 bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp);
 353 }
 354 
 355 /**
 356  * nilfs_bmap_assign - assign a new block number to a block
 357  * @bmap: bmap
 358  * @bhp: pointer to buffer head
 359  * @blocknr: block number
 360  * @binfo: block information
 361  *
 362  * Description: nilfs_bmap_assign() assigns the block number @blocknr to the
 363  * buffer specified by @bh.
 364  *
 365  * Return Value: On success, 0 is returned and the buffer head of a newly
 366  * create buffer and the block information associated with the buffer are
 367  * stored in the place pointed by @bh and @binfo, respectively. On error, one
 368  * of the following negative error codes is returned.
 369  *
 370  * %-EIO - I/O error.
 371  *
 372  * %-ENOMEM - Insufficient amount of memory available.
 373  */
 374 int nilfs_bmap_assign(struct nilfs_bmap *bmap,
 375                       struct buffer_head **bh,
 376                       unsigned long blocknr,
 377                       union nilfs_binfo *binfo)
 378 {
 379         int ret;
 380 
 381         down_write(&bmap->b_sem);
 382         ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo);
 383         up_write(&bmap->b_sem);
 384 
 385         return nilfs_bmap_convert_error(bmap, __func__, ret);
 386 }
 387 
 388 /**
 389  * nilfs_bmap_mark - mark block dirty
 390  * @bmap: bmap
 391  * @key: key
 392  * @level: level
 393  *
 394  * Description: nilfs_bmap_mark() marks the block specified by @key and @level
 395  * as dirty.
 396  *
 397  * Return Value: On success, 0 is returned. On error, one of the following
 398  * negative error codes is returned.
 399  *
 400  * %-EIO - I/O error.
 401  *
 402  * %-ENOMEM - Insufficient amount of memory available.
 403  */
 404 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level)
 405 {
 406         int ret;
 407 
 408         if (bmap->b_ops->bop_mark == NULL)
 409                 return 0;
 410 
 411         down_write(&bmap->b_sem);
 412         ret = bmap->b_ops->bop_mark(bmap, key, level);
 413         up_write(&bmap->b_sem);
 414 
 415         return nilfs_bmap_convert_error(bmap, __func__, ret);
 416 }
 417 
 418 /**
 419  * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state
 420  * @bmap: bmap
 421  *
 422  * Description: nilfs_test_and_clear() is the atomic operation to test and
 423  * clear the dirty state of @bmap.
 424  *
 425  * Return Value: 1 is returned if @bmap is dirty, or 0 if clear.
 426  */
 427 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap)
 428 {
 429         int ret;
 430 
 431         down_write(&bmap->b_sem);
 432         ret = nilfs_bmap_dirty(bmap);
 433         nilfs_bmap_clear_dirty(bmap);
 434         up_write(&bmap->b_sem);
 435         return ret;
 436 }
 437 
 438 
 439 /*
 440  * Internal use only
 441  */
 442 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
 443                               const struct buffer_head *bh)
 444 {
 445         struct buffer_head *pbh;
 446         __u64 key;
 447 
 448         key = page_index(bh->b_page) << (PAGE_SHIFT -
 449                                          bmap->b_inode->i_blkbits);
 450         for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page)
 451                 key++;
 452 
 453         return key;
 454 }
 455 
 456 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
 457 {
 458         __s64 diff;
 459 
 460         diff = key - bmap->b_last_allocated_key;
 461         if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) &&
 462             (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) &&
 463             (bmap->b_last_allocated_ptr + diff > 0))
 464                 return bmap->b_last_allocated_ptr + diff;
 465         else
 466                 return NILFS_BMAP_INVALID_PTR;
 467 }
 468 
 469 #define NILFS_BMAP_GROUP_DIV    8
 470 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
 471 {
 472         struct inode *dat = nilfs_bmap_get_dat(bmap);
 473         unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
 474         unsigned long group = bmap->b_inode->i_ino / entries_per_group;
 475 
 476         return group * entries_per_group +
 477                 (bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
 478                 (entries_per_group / NILFS_BMAP_GROUP_DIV);
 479 }
 480 
 481 static struct lock_class_key nilfs_bmap_dat_lock_key;
 482 static struct lock_class_key nilfs_bmap_mdt_lock_key;
 483 
 484 /**
 485  * nilfs_bmap_read - read a bmap from an inode
 486  * @bmap: bmap
 487  * @raw_inode: on-disk inode
 488  *
 489  * Description: nilfs_bmap_read() initializes the bmap @bmap.
 490  *
 491  * Return Value: On success, 0 is returned. On error, the following negative
 492  * error code is returned.
 493  *
 494  * %-ENOMEM - Insufficient amount of memory available.
 495  */
 496 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
 497 {
 498         if (raw_inode == NULL)
 499                 memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE);
 500         else
 501                 memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE);
 502 
 503         init_rwsem(&bmap->b_sem);
 504         bmap->b_state = 0;
 505         bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
 506         switch (bmap->b_inode->i_ino) {
 507         case NILFS_DAT_INO:
 508                 bmap->b_ptr_type = NILFS_BMAP_PTR_P;
 509                 bmap->b_last_allocated_key = 0;
 510                 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
 511                 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
 512                 break;
 513         case NILFS_CPFILE_INO:
 514         case NILFS_SUFILE_INO:
 515                 bmap->b_ptr_type = NILFS_BMAP_PTR_VS;
 516                 bmap->b_last_allocated_key = 0;
 517                 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
 518                 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
 519                 break;
 520         case NILFS_IFILE_INO:
 521                 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
 522                 /* Fall through */
 523         default:
 524                 bmap->b_ptr_type = NILFS_BMAP_PTR_VM;
 525                 bmap->b_last_allocated_key = 0;
 526                 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
 527                 break;
 528         }
 529 
 530         return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ?
 531                 nilfs_btree_init(bmap) : nilfs_direct_init(bmap);
 532 }
 533 
 534 /**
 535  * nilfs_bmap_write - write back a bmap to an inode
 536  * @bmap: bmap
 537  * @raw_inode: on-disk inode
 538  *
 539  * Description: nilfs_bmap_write() stores @bmap in @raw_inode.
 540  */
 541 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
 542 {
 543         down_write(&bmap->b_sem);
 544         memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
 545                NILFS_INODE_BMAP_SIZE * sizeof(__le64));
 546         if (bmap->b_inode->i_ino == NILFS_DAT_INO)
 547                 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
 548 
 549         up_write(&bmap->b_sem);
 550 }
 551 
 552 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
 553 {
 554         memset(&bmap->b_u, 0, NILFS_BMAP_SIZE);
 555         init_rwsem(&bmap->b_sem);
 556         bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
 557         bmap->b_ptr_type = NILFS_BMAP_PTR_U;
 558         bmap->b_last_allocated_key = 0;
 559         bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
 560         bmap->b_state = 0;
 561         nilfs_btree_init_gc(bmap);
 562 }
 563 
 564 void nilfs_bmap_save(const struct nilfs_bmap *bmap,
 565                      struct nilfs_bmap_store *store)
 566 {
 567         memcpy(store->data, bmap->b_u.u_data, sizeof(store->data));
 568         store->last_allocated_key = bmap->b_last_allocated_key;
 569         store->last_allocated_ptr = bmap->b_last_allocated_ptr;
 570         store->state = bmap->b_state;
 571 }
 572 
 573 void nilfs_bmap_restore(struct nilfs_bmap *bmap,
 574                         const struct nilfs_bmap_store *store)
 575 {
 576         memcpy(bmap->b_u.u_data, store->data, sizeof(store->data));
 577         bmap->b_last_allocated_key = store->last_allocated_key;
 578         bmap->b_last_allocated_ptr = store->last_allocated_ptr;
 579         bmap->b_state = store->state;
 580 }