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