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, 156 unsigned long key, 157 unsigned long rec) 158 { 159 int ret; 160 161 down_write(&bmap->b_sem); 162 ret = nilfs_bmap_do_insert(bmap, key, rec); 163 up_write(&bmap->b_sem); 164 165 return nilfs_bmap_convert_error(bmap, __func__, ret); 166 } 167 168 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key) 169 { 170 __u64 keys[NILFS_BMAP_LARGE_LOW + 1]; 171 __u64 ptrs[NILFS_BMAP_LARGE_LOW + 1]; 172 int ret, n; 173 174 if (bmap->b_ops->bop_check_delete != NULL) { 175 ret = bmap->b_ops->bop_check_delete(bmap, key); 176 if (ret > 0) { 177 n = bmap->b_ops->bop_gather_data( 178 bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1); 179 if (n < 0) 180 return n; 181 ret = nilfs_direct_delete_and_convert( 182 bmap, key, keys, ptrs, n); 183 if (ret == 0) 184 bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE; 185 186 return ret; 187 } else if (ret < 0) 188 return ret; 189 } 190 191 return bmap->b_ops->bop_delete(bmap, key); 192 } 193 194 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, unsigned long *key) 195 { 196 __u64 lastkey; 197 int ret; 198 199 down_read(&bmap->b_sem); 200 ret = bmap->b_ops->bop_last_key(bmap, &lastkey); 201 up_read(&bmap->b_sem); 202 203 if (ret < 0) 204 ret = nilfs_bmap_convert_error(bmap, __func__, ret); 205 else 206 *key = lastkey; 207 return ret; 208 } 209 210 /** 211 * nilfs_bmap_delete - delete a key-record pair from a bmap 212 * @bmap: bmap 213 * @key: key 214 * 215 * Description: nilfs_bmap_delete() deletes the key-record pair specified by 216 * @key from @bmap. 217 * 218 * Return Value: On success, 0 is returned. On error, one of the following 219 * negative error codes is returned. 220 * 221 * %-EIO - I/O error. 222 * 223 * %-ENOMEM - Insufficient amount of memory available. 224 * 225 * %-ENOENT - A record associated with @key does not exist. 226 */ 227 int nilfs_bmap_delete(struct nilfs_bmap *bmap, unsigned long key) 228 { 229 int ret; 230 231 down_write(&bmap->b_sem); 232 ret = nilfs_bmap_do_delete(bmap, key); 233 up_write(&bmap->b_sem); 234 235 return nilfs_bmap_convert_error(bmap, __func__, ret); 236 } 237 238 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, unsigned long key) 239 { 240 __u64 lastkey; 241 int ret; 242 243 ret = bmap->b_ops->bop_last_key(bmap, &lastkey); 244 if (ret < 0) { 245 if (ret == -ENOENT) 246 ret = 0; 247 return ret; 248 } 249 250 while (key <= lastkey) { 251 ret = nilfs_bmap_do_delete(bmap, lastkey); 252 if (ret < 0) 253 return ret; 254 ret = bmap->b_ops->bop_last_key(bmap, &lastkey); 255 if (ret < 0) { 256 if (ret == -ENOENT) 257 ret = 0; 258 return ret; 259 } 260 } 261 return 0; 262 } 263 264 /** 265 * nilfs_bmap_truncate - truncate a bmap to a specified key 266 * @bmap: bmap 267 * @key: key 268 * 269 * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are 270 * greater than or equal to @key from @bmap. 271 * 272 * Return Value: On success, 0 is returned. On error, one of the following 273 * negative error codes is returned. 274 * 275 * %-EIO - I/O error. 276 * 277 * %-ENOMEM - Insufficient amount of memory available. 278 */ 279 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, unsigned long key) 280 { 281 int ret; 282 283 down_write(&bmap->b_sem); 284 ret = nilfs_bmap_do_truncate(bmap, key); 285 up_write(&bmap->b_sem); 286 287 return nilfs_bmap_convert_error(bmap, __func__, ret); 288 } 289 290 /** 291 * nilfs_bmap_clear - free resources a bmap holds 292 * @bmap: bmap 293 * 294 * Description: nilfs_bmap_clear() frees resources associated with @bmap. 295 */ 296 void nilfs_bmap_clear(struct nilfs_bmap *bmap) 297 { 298 down_write(&bmap->b_sem); 299 if (bmap->b_ops->bop_clear != NULL) 300 bmap->b_ops->bop_clear(bmap); 301 up_write(&bmap->b_sem); 302 } 303 304 /** 305 * nilfs_bmap_propagate - propagate dirty state 306 * @bmap: bmap 307 * @bh: buffer head 308 * 309 * Description: nilfs_bmap_propagate() marks the buffers that directly or 310 * indirectly refer to the block specified by @bh dirty. 311 * 312 * Return Value: On success, 0 is returned. On error, one of the following 313 * negative error codes is returned. 314 * 315 * %-EIO - I/O error. 316 * 317 * %-ENOMEM - Insufficient amount of memory available. 318 */ 319 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh) 320 { 321 int ret; 322 323 down_write(&bmap->b_sem); 324 ret = bmap->b_ops->bop_propagate(bmap, bh); 325 up_write(&bmap->b_sem); 326 327 return nilfs_bmap_convert_error(bmap, __func__, ret); 328 } 329 330 /** 331 * nilfs_bmap_lookup_dirty_buffers - 332 * @bmap: bmap 333 * @listp: pointer to buffer head list 334 */ 335 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap, 336 struct list_head *listp) 337 { 338 if (bmap->b_ops->bop_lookup_dirty_buffers != NULL) 339 bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp); 340 } 341 342 /** 343 * nilfs_bmap_assign - assign a new block number to a block 344 * @bmap: bmap 345 * @bhp: pointer to buffer head 346 * @blocknr: block number 347 * @binfo: block information 348 * 349 * Description: nilfs_bmap_assign() assigns the block number @blocknr to the 350 * buffer specified by @bh. 351 * 352 * Return Value: On success, 0 is returned and the buffer head of a newly 353 * create buffer and the block information associated with the buffer are 354 * stored in the place pointed by @bh and @binfo, respectively. On error, one 355 * of the following negative error codes is returned. 356 * 357 * %-EIO - I/O error. 358 * 359 * %-ENOMEM - Insufficient amount of memory available. 360 */ 361 int nilfs_bmap_assign(struct nilfs_bmap *bmap, 362 struct buffer_head **bh, 363 unsigned long blocknr, 364 union nilfs_binfo *binfo) 365 { 366 int ret; 367 368 down_write(&bmap->b_sem); 369 ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo); 370 up_write(&bmap->b_sem); 371 372 return nilfs_bmap_convert_error(bmap, __func__, ret); 373 } 374 375 /** 376 * nilfs_bmap_mark - mark block dirty 377 * @bmap: bmap 378 * @key: key 379 * @level: level 380 * 381 * Description: nilfs_bmap_mark() marks the block specified by @key and @level 382 * as dirty. 383 * 384 * Return Value: On success, 0 is returned. On error, one of the following 385 * negative error codes is returned. 386 * 387 * %-EIO - I/O error. 388 * 389 * %-ENOMEM - Insufficient amount of memory available. 390 */ 391 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level) 392 { 393 int ret; 394 395 if (bmap->b_ops->bop_mark == NULL) 396 return 0; 397 398 down_write(&bmap->b_sem); 399 ret = bmap->b_ops->bop_mark(bmap, key, level); 400 up_write(&bmap->b_sem); 401 402 return nilfs_bmap_convert_error(bmap, __func__, ret); 403 } 404 405 /** 406 * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state 407 * @bmap: bmap 408 * 409 * Description: nilfs_test_and_clear() is the atomic operation to test and 410 * clear the dirty state of @bmap. 411 * 412 * Return Value: 1 is returned if @bmap is dirty, or 0 if clear. 413 */ 414 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap) 415 { 416 int ret; 417 418 down_write(&bmap->b_sem); 419 ret = nilfs_bmap_dirty(bmap); 420 nilfs_bmap_clear_dirty(bmap); 421 up_write(&bmap->b_sem); 422 return ret; 423 } 424 425 426 /* 427 * Internal use only 428 */ 429 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap, 430 const struct buffer_head *bh) 431 { 432 struct buffer_head *pbh; 433 __u64 key; 434 435 key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT - 436 bmap->b_inode->i_blkbits); 437 for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page) 438 key++; 439 440 return key; 441 } 442 443 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key) 444 { 445 __s64 diff; 446 447 diff = key - bmap->b_last_allocated_key; 448 if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) && 449 (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) && 450 (bmap->b_last_allocated_ptr + diff > 0)) 451 return bmap->b_last_allocated_ptr + diff; 452 else 453 return NILFS_BMAP_INVALID_PTR; 454 } 455 456 #define NILFS_BMAP_GROUP_DIV 8 457 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap) 458 { 459 struct inode *dat = nilfs_bmap_get_dat(bmap); 460 unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat); 461 unsigned long group = bmap->b_inode->i_ino / entries_per_group; 462 463 return group * entries_per_group + 464 (bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) * 465 (entries_per_group / NILFS_BMAP_GROUP_DIV); 466 } 467 468 static struct lock_class_key nilfs_bmap_dat_lock_key; 469 static struct lock_class_key nilfs_bmap_mdt_lock_key; 470 471 /** 472 * nilfs_bmap_read - read a bmap from an inode 473 * @bmap: bmap 474 * @raw_inode: on-disk inode 475 * 476 * Description: nilfs_bmap_read() initializes the bmap @bmap. 477 * 478 * Return Value: On success, 0 is returned. On error, the following negative 479 * error code is returned. 480 * 481 * %-ENOMEM - Insufficient amount of memory available. 482 */ 483 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode) 484 { 485 if (raw_inode == NULL) 486 memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE); 487 else 488 memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE); 489 490 init_rwsem(&bmap->b_sem); 491 bmap->b_state = 0; 492 bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode; 493 switch (bmap->b_inode->i_ino) { 494 case NILFS_DAT_INO: 495 bmap->b_ptr_type = NILFS_BMAP_PTR_P; 496 bmap->b_last_allocated_key = 0; 497 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT; 498 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key); 499 break; 500 case NILFS_CPFILE_INO: 501 case NILFS_SUFILE_INO: 502 bmap->b_ptr_type = NILFS_BMAP_PTR_VS; 503 bmap->b_last_allocated_key = 0; 504 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 505 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key); 506 break; 507 case NILFS_IFILE_INO: 508 lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key); 509 /* Fall through */ 510 default: 511 bmap->b_ptr_type = NILFS_BMAP_PTR_VM; 512 bmap->b_last_allocated_key = 0; 513 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 514 break; 515 } 516 517 return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ? 518 nilfs_btree_init(bmap) : nilfs_direct_init(bmap); 519 } 520 521 /** 522 * nilfs_bmap_write - write back a bmap to an inode 523 * @bmap: bmap 524 * @raw_inode: on-disk inode 525 * 526 * Description: nilfs_bmap_write() stores @bmap in @raw_inode. 527 */ 528 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode) 529 { 530 down_write(&bmap->b_sem); 531 memcpy(raw_inode->i_bmap, bmap->b_u.u_data, 532 NILFS_INODE_BMAP_SIZE * sizeof(__le64)); 533 if (bmap->b_inode->i_ino == NILFS_DAT_INO) 534 bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT; 535 536 up_write(&bmap->b_sem); 537 } 538 539 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap) 540 { 541 memset(&bmap->b_u, 0, NILFS_BMAP_SIZE); 542 init_rwsem(&bmap->b_sem); 543 bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode; 544 bmap->b_ptr_type = NILFS_BMAP_PTR_U; 545 bmap->b_last_allocated_key = 0; 546 bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR; 547 bmap->b_state = 0; 548 nilfs_btree_init_gc(bmap); 549 } 550 551 void nilfs_bmap_save(const struct nilfs_bmap *bmap, 552 struct nilfs_bmap_store *store) 553 { 554 memcpy(store->data, bmap->b_u.u_data, sizeof(store->data)); 555 store->last_allocated_key = bmap->b_last_allocated_key; 556 store->last_allocated_ptr = bmap->b_last_allocated_ptr; 557 store->state = bmap->b_state; 558 } 559 560 void nilfs_bmap_restore(struct nilfs_bmap *bmap, 561 const struct nilfs_bmap_store *store) 562 { 563 memcpy(bmap->b_u.u_data, store->data, sizeof(store->data)); 564 bmap->b_last_allocated_key = store->last_allocated_key; 565 bmap->b_last_allocated_ptr = store->last_allocated_ptr; 566 bmap->b_state = store->state; 567 } 568