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