1 #include <linux/module.h> 2 #include <linux/fs.h> 3 #include <linux/blkdev.h> 4 #include <linux/crypto.h> 5 #include <linux/scatterlist.h> 6 #include <linux/swap.h> 7 #include <linux/radix-tree.h> 8 #include "ctree.h" 9 #include "disk-io.h" 10 #include "transaction.h" 11 #include "btrfs_inode.h" 12 13 struct dev_lookup { 14 u64 block_start; 15 u64 num_blocks; 16 u64 device_id; 17 struct block_device *bdev; 18 }; 19 20 int btrfs_insert_dev_radix(struct btrfs_root *root, 21 struct block_device *bdev, 22 u64 device_id, 23 u64 block_start, 24 u64 num_blocks) 25 { 26 struct dev_lookup *lookup; 27 char b[BDEVNAME_SIZE]; 28 int ret; 29 30 lookup = kmalloc(sizeof(*lookup), GFP_NOFS); 31 if (!lookup) 32 return -ENOMEM; 33 lookup->block_start = block_start; 34 lookup->num_blocks = num_blocks; 35 lookup->bdev = bdev; 36 lookup->device_id = device_id; 37 printk("inserting %s into dev radix %Lu %Lu\n", bdevname(bdev, b), block_start, num_blocks); 38 39 ret = radix_tree_insert(&root->fs_info->dev_radix, block_start + 40 num_blocks - 1, lookup); 41 return ret; 42 } 43 44 u64 bh_blocknr(struct buffer_head *bh) 45 { 46 int blkbits = bh->b_page->mapping->host->i_blkbits; 47 u64 blocknr = bh->b_page->index << (PAGE_CACHE_SHIFT - blkbits); 48 unsigned long offset; 49 50 if (PageHighMem(bh->b_page)) 51 offset = (unsigned long)bh->b_data; 52 else 53 offset = bh->b_data - (char *)page_address(bh->b_page); 54 blocknr += offset >> (PAGE_CACHE_SHIFT - blkbits); 55 return blocknr; 56 } 57 58 static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf) 59 { 60 struct btrfs_node *node = btrfs_buffer_node(buf); 61 if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) { 62 printk(KERN_CRIT "bh_blocknr(buf) is %Lu, header is %Lu\n", 63 bh_blocknr(buf), btrfs_header_blocknr(&node->header)); 64 BUG(); 65 } 66 return 0; 67 } 68 69 struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr) 70 { 71 struct address_space *mapping = root->fs_info->btree_inode->i_mapping; 72 int blockbits = root->fs_info->sb->s_blocksize_bits; 73 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits); 74 struct page *page; 75 struct buffer_head *bh; 76 struct buffer_head *head; 77 struct buffer_head *ret = NULL; 78 79 80 page = find_lock_page(mapping, index); 81 if (!page) 82 return NULL; 83 84 if (!page_has_buffers(page)) 85 goto out_unlock; 86 87 head = page_buffers(page); 88 bh = head; 89 do { 90 if (buffer_mapped(bh) && bh_blocknr(bh) == blocknr) { 91 ret = bh; 92 get_bh(bh); 93 goto out_unlock; 94 } 95 bh = bh->b_this_page; 96 } while (bh != head); 97 out_unlock: 98 unlock_page(page); 99 if (ret) { 100 touch_buffer(ret); 101 } 102 page_cache_release(page); 103 return ret; 104 } 105 106 int btrfs_map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh, 107 u64 logical) 108 { 109 struct dev_lookup *lookup[2]; 110 111 int ret; 112 113 root = root->fs_info->dev_root; 114 ret = radix_tree_gang_lookup(&root->fs_info->dev_radix, 115 (void **)lookup, 116 (unsigned long)logical, 117 ARRAY_SIZE(lookup)); 118 if (ret == 0 || lookup[0]->block_start > logical || 119 lookup[0]->block_start + lookup[0]->num_blocks <= logical) { 120 ret = -ENOENT; 121 goto out; 122 } 123 bh->b_bdev = lookup[0]->bdev; 124 bh->b_blocknr = logical - lookup[0]->block_start; 125 set_buffer_mapped(bh); 126 ret = 0; 127 out: 128 return ret; 129 } 130 131 struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root, 132 u64 blocknr) 133 { 134 struct address_space *mapping = root->fs_info->btree_inode->i_mapping; 135 int blockbits = root->fs_info->sb->s_blocksize_bits; 136 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits); 137 struct page *page; 138 struct buffer_head *bh; 139 struct buffer_head *head; 140 struct buffer_head *ret = NULL; 141 int err; 142 u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits); 143 144 page = grab_cache_page(mapping, index); 145 if (!page) 146 return NULL; 147 148 if (!page_has_buffers(page)) 149 create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0); 150 head = page_buffers(page); 151 bh = head; 152 do { 153 if (!buffer_mapped(bh)) { 154 err = btrfs_map_bh_to_logical(root, bh, first_block); 155 BUG_ON(err); 156 } 157 if (bh_blocknr(bh) == blocknr) { 158 ret = bh; 159 get_bh(bh); 160 goto out_unlock; 161 } 162 bh = bh->b_this_page; 163 first_block++; 164 } while (bh != head); 165 out_unlock: 166 unlock_page(page); 167 if (ret) 168 touch_buffer(ret); 169 page_cache_release(page); 170 return ret; 171 } 172 173 static int btree_get_block(struct inode *inode, sector_t iblock, 174 struct buffer_head *bh, int create) 175 { 176 int err; 177 struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root; 178 err = btrfs_map_bh_to_logical(root, bh, iblock); 179 return err; 180 } 181 182 int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len, 183 char *result) 184 { 185 struct scatterlist sg; 186 struct crypto_hash *tfm = root->fs_info->hash_tfm; 187 struct hash_desc desc; 188 int ret; 189 190 desc.tfm = tfm; 191 desc.flags = 0; 192 sg_init_one(&sg, data, len); 193 spin_lock(&root->fs_info->hash_lock); 194 ret = crypto_hash_digest(&desc, &sg, 1, result); 195 spin_unlock(&root->fs_info->hash_lock); 196 if (ret) { 197 printk("sha256 digest failed\n"); 198 } 199 return ret; 200 } 201 static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh, 202 int verify) 203 { 204 char result[BTRFS_CSUM_SIZE]; 205 int ret; 206 struct btrfs_node *node; 207 208 ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE, 209 bh->b_size - BTRFS_CSUM_SIZE, result); 210 if (ret) 211 return ret; 212 if (verify) { 213 if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) { 214 printk("checksum verify failed on %Lu\n", 215 bh_blocknr(bh)); 216 return 1; 217 } 218 } else { 219 node = btrfs_buffer_node(bh); 220 memcpy(node->header.csum, result, BTRFS_CSUM_SIZE); 221 } 222 return 0; 223 } 224 225 static int btree_writepage(struct page *page, struct writeback_control *wbc) 226 { 227 struct buffer_head *bh; 228 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; 229 struct buffer_head *head; 230 if (!page_has_buffers(page)) { 231 create_empty_buffers(page, root->fs_info->sb->s_blocksize, 232 (1 << BH_Dirty)|(1 << BH_Uptodate)); 233 } 234 head = page_buffers(page); 235 bh = head; 236 do { 237 if (buffer_dirty(bh)) 238 csum_tree_block(root, bh, 0); 239 bh = bh->b_this_page; 240 } while (bh != head); 241 return block_write_full_page(page, btree_get_block, wbc); 242 } 243 244 static int btree_readpage(struct file * file, struct page * page) 245 { 246 return block_read_full_page(page, btree_get_block); 247 } 248 249 static struct address_space_operations btree_aops = { 250 .readpage = btree_readpage, 251 .writepage = btree_writepage, 252 .sync_page = block_sync_page, 253 }; 254 255 struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr) 256 { 257 struct buffer_head *bh = NULL; 258 259 bh = btrfs_find_create_tree_block(root, blocknr); 260 if (!bh) 261 return bh; 262 if (buffer_uptodate(bh)) 263 goto uptodate; 264 lock_buffer(bh); 265 if (!buffer_uptodate(bh)) { 266 get_bh(bh); 267 bh->b_end_io = end_buffer_read_sync; 268 submit_bh(READ, bh); 269 wait_on_buffer(bh); 270 if (!buffer_uptodate(bh)) 271 goto fail; 272 csum_tree_block(root, bh, 1); 273 } else { 274 unlock_buffer(bh); 275 } 276 uptodate: 277 if (check_tree_block(root, bh)) 278 BUG(); 279 return bh; 280 fail: 281 brelse(bh); 282 return NULL; 283 } 284 285 int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, 286 struct buffer_head *buf) 287 { 288 WARN_ON(atomic_read(&buf->b_count) == 0); 289 mark_buffer_dirty(buf); 290 return 0; 291 } 292 293 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, 294 struct buffer_head *buf) 295 { 296 WARN_ON(atomic_read(&buf->b_count) == 0); 297 clear_buffer_dirty(buf); 298 return 0; 299 } 300 301 static int __setup_root(int blocksize, 302 struct btrfs_root *root, 303 struct btrfs_fs_info *fs_info, 304 u64 objectid) 305 { 306 root->node = NULL; 307 root->inode = NULL; 308 root->commit_root = NULL; 309 root->blocksize = blocksize; 310 root->ref_cows = 0; 311 root->fs_info = fs_info; 312 root->objectid = objectid; 313 root->last_trans = 0; 314 root->highest_inode = 0; 315 root->last_inode_alloc = 0; 316 memset(&root->root_key, 0, sizeof(root->root_key)); 317 memset(&root->root_item, 0, sizeof(root->root_item)); 318 return 0; 319 } 320 321 static int find_and_setup_root(int blocksize, 322 struct btrfs_root *tree_root, 323 struct btrfs_fs_info *fs_info, 324 u64 objectid, 325 struct btrfs_root *root) 326 { 327 int ret; 328 329 __setup_root(blocksize, root, fs_info, objectid); 330 ret = btrfs_find_last_root(tree_root, objectid, 331 &root->root_item, &root->root_key); 332 BUG_ON(ret); 333 334 root->node = read_tree_block(root, 335 btrfs_root_blocknr(&root->root_item)); 336 BUG_ON(!root->node); 337 return 0; 338 } 339 340 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, 341 struct btrfs_key *location) 342 { 343 struct btrfs_root *root; 344 struct btrfs_root *tree_root = fs_info->tree_root; 345 struct btrfs_path *path; 346 struct btrfs_leaf *l; 347 u64 highest_inode; 348 int ret = 0; 349 350 printk("read_fs_root looking for %Lu %Lu %u\n", location->objectid, location->offset, location->flags); 351 root = radix_tree_lookup(&fs_info->fs_roots_radix, 352 (unsigned long)location->objectid); 353 if (root) { 354 printk("found %p in cache\n", root); 355 return root; 356 } 357 root = kmalloc(sizeof(*root), GFP_NOFS); 358 if (!root) { 359 printk("failed1\n"); 360 return ERR_PTR(-ENOMEM); 361 } 362 if (location->offset == (u64)-1) { 363 ret = find_and_setup_root(fs_info->sb->s_blocksize, 364 fs_info->tree_root, fs_info, 365 location->objectid, root); 366 if (ret) { 367 printk("failed2\n"); 368 kfree(root); 369 return ERR_PTR(ret); 370 } 371 goto insert; 372 } 373 374 __setup_root(fs_info->sb->s_blocksize, root, fs_info, 375 location->objectid); 376 377 path = btrfs_alloc_path(); 378 BUG_ON(!path); 379 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0); 380 if (ret != 0) { 381 printk("internal search_slot gives us %d\n", ret); 382 if (ret > 0) 383 ret = -ENOENT; 384 goto out; 385 } 386 l = btrfs_buffer_leaf(path->nodes[0]); 387 memcpy(&root->root_item, 388 btrfs_item_ptr(l, path->slots[0], struct btrfs_root_item), 389 sizeof(root->root_item)); 390 memcpy(&root->root_key, location, sizeof(*location)); 391 ret = 0; 392 out: 393 btrfs_release_path(root, path); 394 btrfs_free_path(path); 395 if (ret) { 396 kfree(root); 397 return ERR_PTR(ret); 398 } 399 root->node = read_tree_block(root, 400 btrfs_root_blocknr(&root->root_item)); 401 BUG_ON(!root->node); 402 insert: 403 printk("inserting %p\n", root); 404 root->ref_cows = 1; 405 ret = radix_tree_insert(&fs_info->fs_roots_radix, 406 (unsigned long)root->root_key.objectid, 407 root); 408 if (ret) { 409 printk("radix_tree_insert gives us %d\n", ret); 410 brelse(root->node); 411 kfree(root); 412 return ERR_PTR(ret); 413 } 414 ret = btrfs_find_highest_inode(root, &highest_inode); 415 if (ret == 0) { 416 root->highest_inode = highest_inode; 417 root->last_inode_alloc = highest_inode; 418 printk("highest inode is %Lu\n", highest_inode); 419 } 420 printk("all worked\n"); 421 return root; 422 } 423 424 static int btrfs_open_disk(struct btrfs_root *root, u64 device_id, 425 u64 block_start, u64 num_blocks, 426 char *filename, int name_len) 427 { 428 char *null_filename; 429 struct block_device *bdev; 430 int ret; 431 432 null_filename = kmalloc(name_len + 1, GFP_NOFS); 433 if (!null_filename) 434 return -ENOMEM; 435 memcpy(null_filename, filename, name_len); 436 null_filename[name_len] = '\0'; 437 438 bdev = open_bdev_excl(null_filename, O_RDWR, root->fs_info->sb); 439 if (IS_ERR(bdev)) { 440 ret = PTR_ERR(bdev); 441 goto out; 442 } 443 set_blocksize(bdev, root->fs_info->sb->s_blocksize); 444 ret = btrfs_insert_dev_radix(root, bdev, device_id, 445 block_start, num_blocks); 446 BUG_ON(ret); 447 ret = 0; 448 out: 449 kfree(null_filename); 450 return ret; 451 } 452 453 static int read_device_info(struct btrfs_root *root) 454 { 455 struct btrfs_path *path; 456 int ret; 457 struct btrfs_key key; 458 struct btrfs_leaf *leaf; 459 struct btrfs_device_item *dev_item; 460 int nritems; 461 int slot; 462 463 root = root->fs_info->dev_root; 464 465 path = btrfs_alloc_path(); 466 if (!path) 467 return -ENOMEM; 468 key.objectid = 0; 469 key.offset = 0; 470 key.flags = 0; 471 btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY); 472 473 mutex_lock(&root->fs_info->fs_mutex); 474 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 475 leaf = btrfs_buffer_leaf(path->nodes[0]); 476 nritems = btrfs_header_nritems(&leaf->header); 477 while(1) { 478 slot = path->slots[0]; 479 if (slot >= nritems) { 480 ret = btrfs_next_leaf(root, path); 481 if (ret) 482 break; 483 leaf = btrfs_buffer_leaf(path->nodes[0]); 484 nritems = btrfs_header_nritems(&leaf->header); 485 slot = path->slots[0]; 486 } 487 btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key); 488 if (btrfs_key_type(&key) != BTRFS_DEV_ITEM_KEY) { 489 path->slots[0]++; 490 continue; 491 } 492 dev_item = btrfs_item_ptr(leaf, slot, struct btrfs_device_item); 493 printk("found key %Lu %Lu\n", key.objectid, key.offset); 494 if (btrfs_device_id(dev_item) != 495 btrfs_super_device_id(root->fs_info->disk_super)) { 496 ret = btrfs_open_disk(root, btrfs_device_id(dev_item), 497 key.objectid, key.offset, 498 (char *)(dev_item + 1), 499 btrfs_device_pathlen(dev_item)); 500 BUG_ON(ret); 501 } 502 path->slots[0]++; 503 } 504 btrfs_free_path(path); 505 mutex_unlock(&root->fs_info->fs_mutex); 506 return 0; 507 } 508 509 struct btrfs_root *open_ctree(struct super_block *sb) 510 { 511 struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root), 512 GFP_NOFS); 513 struct btrfs_root *dev_root = kmalloc(sizeof(struct btrfs_root), 514 GFP_NOFS); 515 struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root), 516 GFP_NOFS); 517 struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info), 518 GFP_NOFS); 519 int ret; 520 struct btrfs_super_block *disk_super; 521 struct dev_lookup *dev_lookup; 522 523 init_bit_radix(&fs_info->pinned_radix); 524 init_bit_radix(&fs_info->pending_del_radix); 525 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS); 526 INIT_RADIX_TREE(&fs_info->dev_radix, GFP_NOFS); 527 sb_set_blocksize(sb, 4096); 528 fs_info->running_transaction = NULL; 529 fs_info->tree_root = tree_root; 530 fs_info->extent_root = extent_root; 531 fs_info->dev_root = dev_root; 532 fs_info->sb = sb; 533 fs_info->btree_inode = new_inode(sb); 534 fs_info->btree_inode->i_ino = 1; 535 fs_info->btree_inode->i_nlink = 1; 536 fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size; 537 fs_info->btree_inode->i_mapping->a_ops = &btree_aops; 538 BTRFS_I(fs_info->btree_inode)->root = tree_root; 539 memset(&BTRFS_I(fs_info->btree_inode)->location, 0, 540 sizeof(struct btrfs_key)); 541 insert_inode_hash(fs_info->btree_inode); 542 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS); 543 fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC); 544 spin_lock_init(&fs_info->hash_lock); 545 if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) { 546 printk("failed to allocate sha256 hash\n"); 547 return NULL; 548 } 549 mutex_init(&fs_info->trans_mutex); 550 mutex_init(&fs_info->fs_mutex); 551 memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert)); 552 memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert)); 553 554 __setup_root(sb->s_blocksize, dev_root, 555 fs_info, BTRFS_DEV_TREE_OBJECTID); 556 557 __setup_root(sb->s_blocksize, tree_root, 558 fs_info, BTRFS_ROOT_TREE_OBJECTID); 559 560 dev_lookup = kmalloc(sizeof(*dev_lookup), GFP_NOFS); 561 dev_lookup->block_start = 0; 562 dev_lookup->num_blocks = (u32)-2; 563 dev_lookup->bdev = sb->s_bdev; 564 dev_lookup->device_id = 0; 565 ret = radix_tree_insert(&fs_info->dev_radix, (u32)-2, dev_lookup); 566 BUG_ON(ret); 567 fs_info->sb_buffer = read_tree_block(tree_root, 568 BTRFS_SUPER_INFO_OFFSET / 569 sb->s_blocksize); 570 571 if (!fs_info->sb_buffer) 572 return NULL; 573 disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data; 574 if (!btrfs_super_root(disk_super)) 575 return NULL; 576 577 i_size_write(fs_info->btree_inode, 578 btrfs_super_total_blocks(disk_super) << 579 fs_info->btree_inode->i_blkbits); 580 581 radix_tree_delete(&fs_info->dev_radix, (u32)-2); 582 dev_lookup->block_start = btrfs_super_device_block_start(disk_super); 583 dev_lookup->num_blocks = btrfs_super_device_num_blocks(disk_super); 584 dev_lookup->device_id = btrfs_super_device_id(disk_super); 585 586 ret = radix_tree_insert(&fs_info->dev_radix, 587 dev_lookup->block_start + 588 dev_lookup->num_blocks - 1, dev_lookup); 589 BUG_ON(ret); 590 591 fs_info->disk_super = disk_super; 592 593 dev_root->node = read_tree_block(tree_root, 594 btrfs_super_device_root(disk_super)); 595 596 ret = read_device_info(dev_root); 597 BUG_ON(ret); 598 599 tree_root->node = read_tree_block(tree_root, 600 btrfs_super_root(disk_super)); 601 BUG_ON(!tree_root->node); 602 603 mutex_lock(&fs_info->fs_mutex); 604 ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info, 605 BTRFS_EXTENT_TREE_OBJECTID, extent_root); 606 BUG_ON(ret); 607 608 fs_info->generation = btrfs_super_generation(disk_super) + 1; 609 memset(&fs_info->kobj, 0, sizeof(fs_info->kobj)); 610 kobj_set_kset_s(fs_info, btrfs_subsys); 611 kobject_set_name(&fs_info->kobj, "%s", sb->s_id); 612 kobject_register(&fs_info->kobj); 613 mutex_unlock(&fs_info->fs_mutex); 614 return tree_root; 615 } 616 617 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root 618 *root) 619 { 620 struct buffer_head *bh = root->fs_info->sb_buffer; 621 622 btrfs_set_super_root(root->fs_info->disk_super, 623 bh_blocknr(root->fs_info->tree_root->node)); 624 lock_buffer(bh); 625 WARN_ON(atomic_read(&bh->b_count) < 1); 626 clear_buffer_dirty(bh); 627 csum_tree_block(root, bh, 0); 628 bh->b_end_io = end_buffer_write_sync; 629 get_bh(bh); 630 submit_bh(WRITE, bh); 631 wait_on_buffer(bh); 632 if (!buffer_uptodate(bh)) { 633 WARN_ON(1); 634 return -EIO; 635 } 636 return 0; 637 } 638 639 static int free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root) 640 { 641 radix_tree_delete(&fs_info->fs_roots_radix, 642 (unsigned long)root->root_key.objectid); 643 if (root->inode) 644 iput(root->inode); 645 if (root->node) 646 brelse(root->node); 647 if (root->commit_root) 648 brelse(root->commit_root); 649 kfree(root); 650 return 0; 651 } 652 653 int del_fs_roots(struct btrfs_fs_info *fs_info) 654 { 655 int ret; 656 struct btrfs_root *gang[8]; 657 int i; 658 659 while(1) { 660 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, 661 (void **)gang, 0, 662 ARRAY_SIZE(gang)); 663 if (!ret) 664 break; 665 for (i = 0; i < ret; i++) 666 free_fs_root(fs_info, gang[i]); 667 } 668 return 0; 669 } 670 671 static int free_dev_radix(struct btrfs_fs_info *fs_info) 672 { 673 struct dev_lookup *lookup[8]; 674 struct block_device *super_bdev = fs_info->sb->s_bdev; 675 int ret; 676 int i; 677 while(1) { 678 ret = radix_tree_gang_lookup(&fs_info->dev_radix, 679 (void **)lookup, 0, 680 ARRAY_SIZE(lookup)); 681 if (!ret) 682 break; 683 for (i = 0; i < ret; i++) { 684 if (lookup[i]->bdev != super_bdev) 685 close_bdev_excl(lookup[i]->bdev); 686 radix_tree_delete(&fs_info->dev_radix, 687 lookup[i]->block_start + 688 lookup[i]->num_blocks - 1); 689 kfree(lookup[i]); 690 } 691 } 692 return 0; 693 } 694 695 int close_ctree(struct btrfs_root *root) 696 { 697 int ret; 698 struct btrfs_trans_handle *trans; 699 struct btrfs_fs_info *fs_info = root->fs_info; 700 701 mutex_lock(&fs_info->fs_mutex); 702 trans = btrfs_start_transaction(root, 1); 703 btrfs_commit_transaction(trans, root); 704 /* run commit again to drop the original snapshot */ 705 trans = btrfs_start_transaction(root, 1); 706 btrfs_commit_transaction(trans, root); 707 ret = btrfs_write_and_wait_transaction(NULL, root); 708 BUG_ON(ret); 709 write_ctree_super(NULL, root); 710 mutex_unlock(&fs_info->fs_mutex); 711 712 if (fs_info->extent_root->node) 713 btrfs_block_release(fs_info->extent_root, 714 fs_info->extent_root->node); 715 if (fs_info->dev_root->node) 716 btrfs_block_release(fs_info->dev_root, 717 fs_info->dev_root->node); 718 if (fs_info->tree_root->node) 719 btrfs_block_release(fs_info->tree_root, 720 fs_info->tree_root->node); 721 btrfs_block_release(root, fs_info->sb_buffer); 722 crypto_free_hash(fs_info->hash_tfm); 723 truncate_inode_pages(fs_info->btree_inode->i_mapping, 0); 724 iput(fs_info->btree_inode); 725 726 free_dev_radix(fs_info); 727 del_fs_roots(fs_info); 728 kfree(fs_info->extent_root); 729 kfree(fs_info->tree_root); 730 kobject_unregister(&fs_info->kobj); 731 return 0; 732 } 733 734 void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf) 735 { 736 brelse(buf); 737 } 738 739