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