1 /* 2 * bmap.c - NILFS block mapping. 3 * 4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Koji Sato <koji@osrg.net>. 21 */ 22 23 #include <linux/fs.h> 24 #include <linux/string.h> 25 #include <linux/errno.h> 26 #include "nilfs.h" 27 #include "bmap.h" 28 #include "btree.h" 29 #include "direct.h" 30 #include "btnode.h" 31 #include "mdt.h" 32 #include "dat.h" 33 #include "alloc.h" 34 35 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap) 36 { 37 struct the_nilfs *nilfs = bmap->b_inode->i_sb->s_fs_info; 38 39 return nilfs->ns_dat; 40 } 41 42 static int nilfs_bmap_convert_error(struct nilfs_bmap *bmap, 43 const char *fname, int err) 44 { 45 struct inode *inode = bmap->b_inode; 46 47 if (err == -EINVAL) { 48 nilfs_error(inode->i_sb, fname, 49 "broken bmap (inode number=%lu)\n", inode->i_ino); 50 err = -EIO; 51 } 52 return err; 53 } 54 55 /** 56 * nilfs_bmap_lookup_at_level - find a data block or node block 57 * @bmap: bmap 58 * @key: key 59 * @level: level 60 * @ptrp: place to store the value associated to @key 61 * 62 * Description: nilfs_bmap_lookup_at_level() finds a record whose key 63 * matches @key in the block at @level of the bmap. 64 * 65 * Return Value: On success, 0 is returned and the record associated with @key 66 * is stored in the place pointed by @ptrp. On error, one of the following 67 * negative error codes is returned. 68 * 69 * %-EIO - I/O error. 70 * 71 * %-ENOMEM - Insufficient amount of memory available. 72 * 73 * %-ENOENT - A record associated with @key does not exist. 74 */ 75 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level, 76 __u64 *ptrp) 77 { 78 sector_t blocknr; 79 int ret; 80 81 down_read(&bmap->b_sem); 82 ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp); 83 if (ret < 0) { 84 ret = nilfs_bmap_convert_error(bmap, __func__, ret); 85 goto out; 86 } 87 if (NILFS_BMAP_USE_VBN(bmap)) { 88 ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp, 89 &blocknr); 90 if (!ret) 91 *ptrp = blocknr; 92 } 93 94 out: 95 up_read(&bmap->b_sem); 96 return ret; 97 } 98 99 int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp, 100 unsigned maxblocks) 101 { 102 int ret; 103 104 down_read(&bmap->b_sem); 105 ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks); 106 up_read(&bmap->b_sem); 107 108 return nilfs_bmap_convert_error(bmap, __func__, ret); 109 } 110 111 static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr) 112 { 113 __u64 keys[NILFS_BMAP_SMALL_HIGH + 1]; 114 __u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1]; 115 int ret, n; 116 117 if (bmap->b_ops->bop_check_insert != NULL) { 118 ret = bmap->b_ops->bop_check_insert(bmap, key); 119 if (ret > 0) { 120 n = bmap->b_ops->bop_gather_data( 121 bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1); 122 if (n < 0) 123 return n; 124 ret = nilfs_btree_convert_and_insert( 125 bmap, key, ptr, keys, ptrs, n); 126 if (ret == 0) 127 bmap->b_u.u_flags |= NILFS_BMAP_LARGE; 128 129 return ret; 130 } else if (ret < 0) 131 return ret; 132 } 133 134 return bmap->b_ops->bop_insert(bmap, key, ptr); 135 } 136 137 /** 138 * nilfs_bmap_insert - insert a new key-record pair into a bmap 139 * @bmap: bmap 140 * @key: key 141 * @rec: record 142 * 143 * Description: nilfs_bmap_insert() inserts the new key-record pair specified 144 * by @key and @rec into @bmap. 145 * 146 * Return Value: On success, 0 is returned. On error, one of the following 147 * negative error codes is returned. 148 * 149 * %-EIO - I/O error. 150 * 151 * %-ENOMEM - Insufficient amount of memory available. 152 * 153 * %-EEXIST - A record associated with @key already exist. 154 */ 155 int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec) 156 { 157 int ret; 158 159 down_write(&bmap->b_sem); 160 ret = nilfs_bmap_do_insert(bmap, key, rec); 161 up_write(&bmap->b_sem); 162 163 return nilfs_bmap_convert_error(bmap, __func__, ret); 164 } 165 166 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key) 167 { 168 __u64 keys[NILFS_BMAP_LARGE_LOW + 1]; 169 __u64 ptrs[NILFS_BMAP_LARGE_LOW + 1]; 170 int ret, n; 171 172 if (bmap->b_ops->bop_check_delete != NULL) { 173 ret = bmap->b_ops->bop_check_delete(bmap, key); 174 if (ret > 0) { 175 n = bmap->b_ops->bop_gather_data( 176 bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1); 177 if (n < 0) 178 return n; 179 ret = nilfs_direct_delete_and_convert( 180 bmap, key, keys, ptrs, n); 181 if (ret == 0) 182 bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE; 183 184 return ret; 185 } else if (ret < 0) 186 return ret; 187 } 188 189 return bmap->b_ops->bop_delete(bmap, key); 190 } 191 192 /** 193 * nilfs_bmap_seek_key - seek a valid entry and return its key 194 * @bmap: bmap struct 195 * @start: start key number 196 * @keyp: place to store valid key 197 * 198 * Description: nilfs_bmap_seek_key() seeks a valid key on @bmap 199 * starting from @start, and stores it to @keyp if found. 200 * 201 * Return Value: On success, 0 is returned. On error, one of the following 202 * negative error codes is returned. 203 * 204 * %-EIO - I/O error. 205 * 206 * %-ENOMEM - Insufficient amount of memory available. 207 * 208 * %-ENOENT - No valid entry was found 209 */ 210 int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp) 211 { 212 int ret; 213 214 down_read(&bmap->b_sem); 215 ret = bmap->b_ops->bop_seek_key(bmap, start, 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 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp) 224 { 225 int ret; 226 227 down_read(&bmap->b_sem); 228 ret = bmap->b_ops->bop_last_key(bmap, keyp); 229 up_read(&bmap->b_sem); 230 231 if (ret < 0) 232 ret = nilfs_bmap_convert_error(bmap, __func__, ret); 233 return ret; 234 } 235 236 /** 237 * nilfs_bmap_delete - delete a key-record pair from a bmap 238 * @bmap: bmap 239 * @key: key 240 * 241 * Description: nilfs_bmap_delete() deletes the key-record pair specified by 242 * @key from @bmap. 243 * 244 * Return Value: On success, 0 is returned. On error, one of the following 245 * negative error codes is returned. 246 * 247 * %-EIO - I/O error. 248 * 249 * %-ENOMEM - Insufficient amount of memory available. 250 * 251 * %-ENOENT - A record associated with @key does not exist. 252 */ 253 int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key) 254 { 255 int ret; 256 257 down_write(&bmap->b_sem); 258 ret = nilfs_bmap_do_delete(bmap, key); 259 up_write(&bmap->b_sem); 260 261 return nilfs_bmap_convert_error(bmap, __func__, ret); 262 } 263 264 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, __u64 key) 265 { 266 __u64 lastkey; 267 int ret; 268 269 ret = bmap->b_ops->bop_last_key(bmap, &lastkey); 270 if (ret < 0) { 271 if (ret == -ENOENT) 272 ret = 0; 273 return ret; 274 } 275 276 while (key <= lastkey) { 277 ret = nilfs_bmap_do_delete(bmap, lastkey); 278 if (ret < 0) 279 return ret; 280 ret = bmap->b_ops->bop_last_key(bmap, &lastkey); 281 if (ret < 0) { 282 if (ret == -ENOENT) 283 ret = 0; 284 return ret; 285 } 286 } 287 return 0; 288 } 289 290 /** 291 * nilfs_bmap_truncate - truncate a bmap to a specified key 292 * @bmap: bmap 293 * @key: key 294 * 295 * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are 296 * greater than or equal to @key from @bmap. 297 * 298 * Return Value: On success, 0 is returned. On error, one of the following 299 * negative error codes is returned. 300 * 301 * %-EIO - I/O error. 302 * 303 * %-ENOMEM - Insufficient amount of memory available. 304 */ 305 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key) 306 { 307 int ret; 308 309 down_write(&bmap->b_sem); 310 ret = nilfs_bmap_do_truncate(bmap, key); 311 up_write(&bmap->b_sem); 312 313 return nilfs_bmap_convert_error(bmap, __func__, ret); 314 } 315 316 /** 317 * nilfs_bmap_clear - free resources a bmap holds 318 * @bmap: bmap 319 * 320 * Description: nilfs_bmap_clear() frees resources associated with @bmap. 321 */ 322 void nilfs_bmap_clear(struct nilfs_bmap *bmap) 323 { 324 down_write(&bmap->b_sem); 325 if (bmap->b_ops->bop_clear != NULL) 326 bmap->b_ops->bop_clear(bmap); 327 up_write(&bmap->b_sem); 328 } 329 330 /** 331 * nilfs_bmap_propagate - propagate dirty state 332 * @bmap: bmap 333 * @bh: buffer head 334 * 335 * Description: nilfs_bmap_propagate() marks the buffers that directly or 336 * indirectly refer to the block specified by @bh dirty. 337 * 338 * Return Value: On success, 0 is returned. On error, one of the following 339 * negative error codes is returned. 340 * 341 * %-EIO - I/O error. 342 * 343 * %-ENOMEM - Insufficient amount of memory available. 344 */ 345 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh) 346 { 347 int ret; 348 349 down_write(&bmap->b_sem); 350 ret = bmap->b_ops->bop_propagate(bmap, bh); 351 up_write(&bmap->b_sem); 352 353 return nilfs_bmap_convert_error(bmap, __func__, ret); 354 } 355 356 /** 357 * nilfs_bmap_lookup_dirty_buffers - 358 * @bmap: bmap 359 * @listp: pointer to buffer head list 360 */ 361 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap, 362 struct list_head *listp) 363 { 364 if (bmap->b_ops->bop_lookup_dirty_buffers != NULL) 365 bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp); 366 } 367 368 /** 369 * nilfs_bmap_assign - assign a new block number to a block 370 * @bmap: bmap 371 * @bhp: pointer to buffer head 372 * @blocknr: block number 373 * @binfo: block information 374 * 375 * Description: nilfs_bmap_assign() assigns the block number @blocknr to the 376 * buffer specified by @bh. 377 * 378 * Return Value: On success, 0 is returned and the buffer head of a newly 379 * create buffer and the block information associated with the buffer are 380 * stored in the place pointed by @bh and @binfo, respectively. On error, one 381 * of the following negative error codes is returned. 382 * 383 * %-EIO - I/O error. 384 * 385 * %-ENOMEM - Insufficient amount of memory available. 386 */ 387 int nilfs_bmap_assign(struct nilfs_bmap *bmap, 388 struct buffer_head **bh, 389 unsigned long blocknr, 390 union nilfs_binfo *binfo) 391 { 392 int ret; 393 394 down_write(&bmap->b_sem); 395 ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo); 396 up_write(&bmap->b_sem); 397 398 return nilfs_bmap_convert_error(bmap, __func__, ret); 399 } 400 401 /** 402 * nilfs_bmap_mark - mark block dirty 403 * @bmap: bmap 404 * @key: key 405 * @level: level 406 * 407 * Description: nilfs_bmap_mark() marks the block specified by @key and @level 408 * as dirty. 409 * 410 * Return Value: On success, 0 is returned. On error, one of the following 411 * negative error codes is returned. 412 * 413 * %-EIO - I/O error. 414 * 415 * %-ENOMEM - Insufficient amount of memory available. 416 */ 417 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level) 418 { 419 int ret; 420 421 if (bmap->b_ops->bop_mark == NULL) 422 return 0; 423 424 down_write(&bmap->b_sem); 425 ret = bmap->b_ops->bop_mark(bmap, key, level); 426 up_write(&bmap->b_sem); 427 428 return nilfs_bmap_convert_error(bmap, __func__, ret); 429 } 430 431 /** 432 * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state 433 * @bmap: bmap 434 * 435 * Description: nilfs_test_and_clear() is the atomic operation to test and 436 * clear the dirty state of @bmap. 437 * 438 * Return Value: 1 is returned if @bmap is dirty, or 0 if clear. 439 */ 440 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap) 441 { 442 int ret; 443 444 down_write(&bmap->b_sem); 445 ret = nilfs_bmap_dirty(bmap); 446 nilfs_bmap_clear_dirty(bmap); 447 up_write(&bmap->b_sem); 448 return ret; 449 } 450 451 452 /* 453 * Internal use only 454 */ 455 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap, 456 const struct buffer_head *bh) 457 { 458 struct buffer_head *pbh; 459 __u64 key; 460 461 key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT - 462 bmap->b_inode->i_blkbits); 463 for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page) 464 key++; 465 466 return key; 467 } 468 469 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key) 470 { 471 __s64 diff; 472 473 diff = key - bmap->b_last_allocated_key; 474 if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) && 475 (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) && 476 (bmap->b_last_allocated_ptr + diff > 0)) 477 return bmap->b_last_allocated_ptr + diff; 478 else 479 return NILFS_BMAP_INVALID_PTR; 480 } 481 482 #define NILFS_BMAP_GROUP_DIV 8 483 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap) 484 { 485 struct inode *dat = nilfs_bmap_get_dat(bmap); 486 unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat); 487 unsigned long group = bmap->b_inode->i_ino / entries_per_group; 488 489 return group * entries_per_group + 490 (bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) * 491 (entries_per_group / NILFS_BMAP_GROUP_DIV); 492 } 493 494 static struct lock_class_key nilfs_bmap_dat_lock_key; 495 static struct lock_class_key nilfs_bmap_mdt_lock_key; 496 497 /** 498 * nilfs_bmap_read - read a bmap from an inode 499 * @bmap: bmap 500 * @raw_inode: on-disk inode 501 * 502 * Description: nilfs_bmap_read() initializes the bmap @bmap. 503 * 504 * Return Value: On success, 0 is returned. On error, the following negative 505 * error code is returned. 506 * 507 * %-ENOMEM - Insufficient amount of memory available. 508 */ 509 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode) 510 { 511 if (raw_inode == NULL) 512 memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE); 513 else 514 memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE); 515 516 init_rwsem(&bmap->b_sem); 517 bmap->b_state = 0; 518 bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode; 519 switch (bmap->b_inode->i_ino) { 520 case NILFS_DAT_INO: 521 bmap->b_ptr_type = NILFS_BMAP_PTR_P; 522 bmap->b_last_allocated_key = 0; 523 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT; 524 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key); 525 break; 526 case NILFS_CPFILE_INO: 527 case NILFS_SUFILE_INO: 528 bmap->b_ptr_type = NILFS_BMAP_PTR_VS; 529 bmap->b_last_allocated_key = 0; 530 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 531 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key); 532 break; 533 case NILFS_IFILE_INO: 534 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key); 535 /* Fall through */ 536 default: 537 bmap->b_ptr_type = NILFS_BMAP_PTR_VM; 538 bmap->b_last_allocated_key = 0; 539 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 540 break; 541 } 542 543 return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ? 544 nilfs_btree_init(bmap) : nilfs_direct_init(bmap); 545 } 546 547 /** 548 * nilfs_bmap_write - write back a bmap to an inode 549 * @bmap: bmap 550 * @raw_inode: on-disk inode 551 * 552 * Description: nilfs_bmap_write() stores @bmap in @raw_inode. 553 */ 554 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode) 555 { 556 down_write(&bmap->b_sem); 557 memcpy(raw_inode->i_bmap, bmap->b_u.u_data, 558 NILFS_INODE_BMAP_SIZE * sizeof(__le64)); 559 if (bmap->b_inode->i_ino == NILFS_DAT_INO) 560 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT; 561 562 up_write(&bmap->b_sem); 563 } 564 565 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap) 566 { 567 memset(&bmap->b_u, 0, NILFS_BMAP_SIZE); 568 init_rwsem(&bmap->b_sem); 569 bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode; 570 bmap->b_ptr_type = NILFS_BMAP_PTR_U; 571 bmap->b_last_allocated_key = 0; 572 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 573 bmap->b_state = 0; 574 nilfs_btree_init_gc(bmap); 575 } 576 577 void nilfs_bmap_save(const struct nilfs_bmap *bmap, 578 struct nilfs_bmap_store *store) 579 { 580 memcpy(store->data, bmap->b_u.u_data, sizeof(store->data)); 581 store->last_allocated_key = bmap->b_last_allocated_key; 582 store->last_allocated_ptr = bmap->b_last_allocated_ptr; 583 store->state = bmap->b_state; 584 } 585 586 void nilfs_bmap_restore(struct nilfs_bmap *bmap, 587 const struct nilfs_bmap_store *store) 588 { 589 memcpy(bmap->b_u.u_data, store->data, sizeof(store->data)); 590 bmap->b_last_allocated_key = store->last_allocated_key; 591 bmap->b_last_allocated_ptr = store->last_allocated_ptr; 592 bmap->b_state = store->state; 593 } 594