| 1 | /* |
| 2 | * Copyright (C) 2007 Oracle. All rights reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public |
| 6 | * License v2 as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 11 | * General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public |
| 14 | * License along with this program; if not, write to the |
| 15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 16 | * Boston, MA 021110-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/crc32c.h> |
| 21 | #include <linux/pagemap.h> |
| 22 | #include "hash.h" |
| 23 | #include "ctree.h" |
| 24 | #include "disk-io.h" |
| 25 | #include "print-tree.h" |
| 26 | #include "transaction.h" |
| 27 | #include "volumes.h" |
| 28 | |
| 29 | #define BLOCK_GROUP_DATA EXTENT_WRITEBACK |
| 30 | #define BLOCK_GROUP_METADATA EXTENT_UPTODATE |
| 31 | #define BLOCK_GROUP_SYSTEM EXTENT_NEW |
| 32 | |
| 33 | #define BLOCK_GROUP_DIRTY EXTENT_DIRTY |
| 34 | |
| 35 | static int finish_current_insert(struct btrfs_trans_handle *trans, struct |
| 36 | btrfs_root *extent_root); |
| 37 | static int del_pending_extents(struct btrfs_trans_handle *trans, struct |
| 38 | btrfs_root *extent_root); |
| 39 | int btrfs_make_block_group(struct btrfs_trans_handle *trans, |
| 40 | struct btrfs_root *root, u64 bytes_used, |
| 41 | u64 type, u64 chunk_tree, u64 chunk_objectid, |
| 42 | u64 size); |
| 43 | |
| 44 | |
| 45 | static int cache_block_group(struct btrfs_root *root, |
| 46 | struct btrfs_block_group_cache *block_group) |
| 47 | { |
| 48 | struct btrfs_path *path; |
| 49 | int ret; |
| 50 | struct btrfs_key key; |
| 51 | struct extent_buffer *leaf; |
| 52 | struct extent_io_tree *free_space_cache; |
| 53 | int slot; |
| 54 | u64 last = 0; |
| 55 | u64 hole_size; |
| 56 | u64 first_free; |
| 57 | int found = 0; |
| 58 | |
| 59 | if (!block_group) |
| 60 | return 0; |
| 61 | |
| 62 | root = root->fs_info->extent_root; |
| 63 | free_space_cache = &root->fs_info->free_space_cache; |
| 64 | |
| 65 | if (block_group->cached) |
| 66 | return 0; |
| 67 | |
| 68 | path = btrfs_alloc_path(); |
| 69 | if (!path) |
| 70 | return -ENOMEM; |
| 71 | |
| 72 | path->reada = 2; |
| 73 | first_free = block_group->key.objectid; |
| 74 | key.objectid = block_group->key.objectid; |
| 75 | key.offset = 0; |
| 76 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 77 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 78 | if (ret < 0) |
| 79 | return ret; |
| 80 | ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY); |
| 81 | if (ret < 0) |
| 82 | return ret; |
| 83 | if (ret == 0) { |
| 84 | leaf = path->nodes[0]; |
| 85 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
| 86 | if (key.objectid + key.offset > first_free) |
| 87 | first_free = key.objectid + key.offset; |
| 88 | } |
| 89 | while(1) { |
| 90 | leaf = path->nodes[0]; |
| 91 | slot = path->slots[0]; |
| 92 | if (slot >= btrfs_header_nritems(leaf)) { |
| 93 | ret = btrfs_next_leaf(root, path); |
| 94 | if (ret < 0) |
| 95 | goto err; |
| 96 | if (ret == 0) { |
| 97 | continue; |
| 98 | } else { |
| 99 | break; |
| 100 | } |
| 101 | } |
| 102 | btrfs_item_key_to_cpu(leaf, &key, slot); |
| 103 | if (key.objectid < block_group->key.objectid) { |
| 104 | goto next; |
| 105 | } |
| 106 | if (key.objectid >= block_group->key.objectid + |
| 107 | block_group->key.offset) { |
| 108 | break; |
| 109 | } |
| 110 | |
| 111 | if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) { |
| 112 | if (!found) { |
| 113 | last = first_free; |
| 114 | found = 1; |
| 115 | } |
| 116 | if (key.objectid > last) { |
| 117 | hole_size = key.objectid - last; |
| 118 | set_extent_dirty(free_space_cache, last, |
| 119 | last + hole_size - 1, |
| 120 | GFP_NOFS); |
| 121 | } |
| 122 | last = key.objectid + key.offset; |
| 123 | } |
| 124 | next: |
| 125 | path->slots[0]++; |
| 126 | } |
| 127 | |
| 128 | if (!found) |
| 129 | last = first_free; |
| 130 | if (block_group->key.objectid + |
| 131 | block_group->key.offset > last) { |
| 132 | hole_size = block_group->key.objectid + |
| 133 | block_group->key.offset - last; |
| 134 | set_extent_dirty(free_space_cache, last, |
| 135 | last + hole_size - 1, GFP_NOFS); |
| 136 | } |
| 137 | block_group->cached = 1; |
| 138 | err: |
| 139 | btrfs_free_path(path); |
| 140 | return 0; |
| 141 | } |
| 142 | |
| 143 | struct btrfs_block_group_cache *btrfs_lookup_block_group(struct |
| 144 | btrfs_fs_info *info, |
| 145 | u64 bytenr) |
| 146 | { |
| 147 | struct extent_io_tree *block_group_cache; |
| 148 | struct btrfs_block_group_cache *block_group = NULL; |
| 149 | u64 ptr; |
| 150 | u64 start; |
| 151 | u64 end; |
| 152 | int ret; |
| 153 | |
| 154 | block_group_cache = &info->block_group_cache; |
| 155 | ret = find_first_extent_bit(block_group_cache, |
| 156 | bytenr, &start, &end, |
| 157 | BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | |
| 158 | BLOCK_GROUP_SYSTEM); |
| 159 | if (ret) { |
| 160 | return NULL; |
| 161 | } |
| 162 | ret = get_state_private(block_group_cache, start, &ptr); |
| 163 | if (ret) |
| 164 | return NULL; |
| 165 | |
| 166 | block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr; |
| 167 | if (block_group->key.objectid <= bytenr && bytenr < |
| 168 | block_group->key.objectid + block_group->key.offset) |
| 169 | return block_group; |
| 170 | return NULL; |
| 171 | } |
| 172 | |
| 173 | static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits) |
| 174 | { |
| 175 | return (cache->flags & bits) == bits; |
| 176 | } |
| 177 | |
| 178 | static int noinline find_search_start(struct btrfs_root *root, |
| 179 | struct btrfs_block_group_cache **cache_ret, |
| 180 | u64 *start_ret, int num, int data) |
| 181 | { |
| 182 | int ret; |
| 183 | struct btrfs_block_group_cache *cache = *cache_ret; |
| 184 | struct extent_io_tree *free_space_cache; |
| 185 | struct extent_state *state; |
| 186 | u64 last; |
| 187 | u64 start = 0; |
| 188 | u64 cache_miss = 0; |
| 189 | u64 total_fs_bytes; |
| 190 | u64 search_start = *start_ret; |
| 191 | int wrapped = 0; |
| 192 | |
| 193 | if (!cache) |
| 194 | goto out; |
| 195 | total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy); |
| 196 | free_space_cache = &root->fs_info->free_space_cache; |
| 197 | |
| 198 | again: |
| 199 | ret = cache_block_group(root, cache); |
| 200 | if (ret) |
| 201 | goto out; |
| 202 | |
| 203 | last = max(search_start, cache->key.objectid); |
| 204 | if (!block_group_bits(cache, data)) { |
| 205 | goto new_group; |
| 206 | } |
| 207 | |
| 208 | spin_lock_irq(&free_space_cache->lock); |
| 209 | state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY); |
| 210 | while(1) { |
| 211 | if (!state) { |
| 212 | if (!cache_miss) |
| 213 | cache_miss = last; |
| 214 | spin_unlock_irq(&free_space_cache->lock); |
| 215 | goto new_group; |
| 216 | } |
| 217 | |
| 218 | start = max(last, state->start); |
| 219 | last = state->end + 1; |
| 220 | if (last - start < num) { |
| 221 | if (last == cache->key.objectid + cache->key.offset) |
| 222 | cache_miss = start; |
| 223 | do { |
| 224 | state = extent_state_next(state); |
| 225 | } while(state && !(state->state & EXTENT_DIRTY)); |
| 226 | continue; |
| 227 | } |
| 228 | spin_unlock_irq(&free_space_cache->lock); |
| 229 | if (start + num > cache->key.objectid + cache->key.offset) |
| 230 | goto new_group; |
| 231 | if (start + num > total_fs_bytes) |
| 232 | goto new_group; |
| 233 | if (!block_group_bits(cache, data)) { |
| 234 | printk("block group bits don't match %Lu %Lu\n", cache->flags, data); |
| 235 | } |
| 236 | *start_ret = start; |
| 237 | return 0; |
| 238 | } |
| 239 | out: |
| 240 | cache = btrfs_lookup_block_group(root->fs_info, search_start); |
| 241 | if (!cache) { |
| 242 | printk("Unable to find block group for %Lu\n", search_start); |
| 243 | WARN_ON(1); |
| 244 | } |
| 245 | return -ENOSPC; |
| 246 | |
| 247 | new_group: |
| 248 | last = cache->key.objectid + cache->key.offset; |
| 249 | wrapped: |
| 250 | cache = btrfs_lookup_block_group(root->fs_info, last); |
| 251 | if (!cache || cache->key.objectid >= total_fs_bytes) { |
| 252 | no_cache: |
| 253 | if (!wrapped) { |
| 254 | wrapped = 1; |
| 255 | last = search_start; |
| 256 | goto wrapped; |
| 257 | } |
| 258 | goto out; |
| 259 | } |
| 260 | if (cache_miss && !cache->cached) { |
| 261 | cache_block_group(root, cache); |
| 262 | last = cache_miss; |
| 263 | cache = btrfs_lookup_block_group(root->fs_info, last); |
| 264 | } |
| 265 | cache = btrfs_find_block_group(root, cache, last, data, 0); |
| 266 | if (!cache) |
| 267 | goto no_cache; |
| 268 | *cache_ret = cache; |
| 269 | cache_miss = 0; |
| 270 | goto again; |
| 271 | } |
| 272 | |
| 273 | static u64 div_factor(u64 num, int factor) |
| 274 | { |
| 275 | if (factor == 10) |
| 276 | return num; |
| 277 | num *= factor; |
| 278 | do_div(num, 10); |
| 279 | return num; |
| 280 | } |
| 281 | |
| 282 | static int block_group_state_bits(u64 flags) |
| 283 | { |
| 284 | int bits = 0; |
| 285 | if (flags & BTRFS_BLOCK_GROUP_DATA) |
| 286 | bits |= BLOCK_GROUP_DATA; |
| 287 | if (flags & BTRFS_BLOCK_GROUP_METADATA) |
| 288 | bits |= BLOCK_GROUP_METADATA; |
| 289 | if (flags & BTRFS_BLOCK_GROUP_SYSTEM) |
| 290 | bits |= BLOCK_GROUP_SYSTEM; |
| 291 | return bits; |
| 292 | } |
| 293 | |
| 294 | struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root, |
| 295 | struct btrfs_block_group_cache |
| 296 | *hint, u64 search_start, |
| 297 | int data, int owner) |
| 298 | { |
| 299 | struct btrfs_block_group_cache *cache; |
| 300 | struct extent_io_tree *block_group_cache; |
| 301 | struct btrfs_block_group_cache *found_group = NULL; |
| 302 | struct btrfs_fs_info *info = root->fs_info; |
| 303 | u64 used; |
| 304 | u64 last = 0; |
| 305 | u64 hint_last; |
| 306 | u64 start; |
| 307 | u64 end; |
| 308 | u64 free_check; |
| 309 | u64 ptr; |
| 310 | u64 total_fs_bytes; |
| 311 | int bit; |
| 312 | int ret; |
| 313 | int full_search = 0; |
| 314 | int factor = 8; |
| 315 | |
| 316 | block_group_cache = &info->block_group_cache; |
| 317 | total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy); |
| 318 | |
| 319 | if (!owner) |
| 320 | factor = 8; |
| 321 | |
| 322 | bit = block_group_state_bits(data); |
| 323 | |
| 324 | if (search_start && search_start < total_fs_bytes) { |
| 325 | struct btrfs_block_group_cache *shint; |
| 326 | shint = btrfs_lookup_block_group(info, search_start); |
| 327 | if (shint && block_group_bits(shint, data)) { |
| 328 | used = btrfs_block_group_used(&shint->item); |
| 329 | if (used + shint->pinned < |
| 330 | div_factor(shint->key.offset, factor)) { |
| 331 | return shint; |
| 332 | } |
| 333 | } |
| 334 | } |
| 335 | if (hint && block_group_bits(hint, data) && |
| 336 | hint->key.objectid < total_fs_bytes) { |
| 337 | used = btrfs_block_group_used(&hint->item); |
| 338 | if (used + hint->pinned < |
| 339 | div_factor(hint->key.offset, factor)) { |
| 340 | return hint; |
| 341 | } |
| 342 | last = hint->key.objectid + hint->key.offset; |
| 343 | hint_last = last; |
| 344 | } else { |
| 345 | if (hint) |
| 346 | hint_last = max(hint->key.objectid, search_start); |
| 347 | else |
| 348 | hint_last = search_start; |
| 349 | |
| 350 | if (hint_last >= total_fs_bytes) |
| 351 | hint_last = search_start; |
| 352 | last = hint_last; |
| 353 | } |
| 354 | again: |
| 355 | while(1) { |
| 356 | ret = find_first_extent_bit(block_group_cache, last, |
| 357 | &start, &end, bit); |
| 358 | if (ret) |
| 359 | break; |
| 360 | |
| 361 | ret = get_state_private(block_group_cache, start, &ptr); |
| 362 | if (ret) |
| 363 | break; |
| 364 | |
| 365 | cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; |
| 366 | last = cache->key.objectid + cache->key.offset; |
| 367 | used = btrfs_block_group_used(&cache->item); |
| 368 | |
| 369 | if (cache->key.objectid > total_fs_bytes) |
| 370 | break; |
| 371 | |
| 372 | if (block_group_bits(cache, data)) { |
| 373 | if (full_search) |
| 374 | free_check = cache->key.offset; |
| 375 | else |
| 376 | free_check = div_factor(cache->key.offset, |
| 377 | factor); |
| 378 | |
| 379 | if (used + cache->pinned < free_check) { |
| 380 | found_group = cache; |
| 381 | goto found; |
| 382 | } |
| 383 | } |
| 384 | cond_resched(); |
| 385 | } |
| 386 | if (!full_search) { |
| 387 | last = search_start; |
| 388 | full_search = 1; |
| 389 | goto again; |
| 390 | } |
| 391 | found: |
| 392 | return found_group; |
| 393 | } |
| 394 | |
| 395 | static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation, |
| 396 | u64 owner, u64 owner_offset) |
| 397 | { |
| 398 | u32 high_crc = ~(u32)0; |
| 399 | u32 low_crc = ~(u32)0; |
| 400 | __le64 lenum; |
| 401 | |
| 402 | lenum = cpu_to_le64(root_objectid); |
| 403 | high_crc = crc32c(high_crc, &lenum, sizeof(lenum)); |
| 404 | lenum = cpu_to_le64(ref_generation); |
| 405 | low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); |
| 406 | if (owner >= BTRFS_FIRST_FREE_OBJECTID) { |
| 407 | lenum = cpu_to_le64(owner); |
| 408 | low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); |
| 409 | lenum = cpu_to_le64(owner_offset); |
| 410 | low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); |
| 411 | } |
| 412 | return ((u64)high_crc << 32) | (u64)low_crc; |
| 413 | } |
| 414 | |
| 415 | static int match_extent_ref(struct extent_buffer *leaf, |
| 416 | struct btrfs_extent_ref *disk_ref, |
| 417 | struct btrfs_extent_ref *cpu_ref) |
| 418 | { |
| 419 | int ret; |
| 420 | int len; |
| 421 | |
| 422 | if (cpu_ref->objectid) |
| 423 | len = sizeof(*cpu_ref); |
| 424 | else |
| 425 | len = 2 * sizeof(u64); |
| 426 | ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref, |
| 427 | len); |
| 428 | return ret == 0; |
| 429 | } |
| 430 | |
| 431 | static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans, |
| 432 | struct btrfs_root *root, |
| 433 | struct btrfs_path *path, u64 bytenr, |
| 434 | u64 root_objectid, |
| 435 | u64 ref_generation, u64 owner, |
| 436 | u64 owner_offset, int del) |
| 437 | { |
| 438 | u64 hash; |
| 439 | struct btrfs_key key; |
| 440 | struct btrfs_key found_key; |
| 441 | struct btrfs_extent_ref ref; |
| 442 | struct extent_buffer *leaf; |
| 443 | struct btrfs_extent_ref *disk_ref; |
| 444 | int ret; |
| 445 | int ret2; |
| 446 | |
| 447 | btrfs_set_stack_ref_root(&ref, root_objectid); |
| 448 | btrfs_set_stack_ref_generation(&ref, ref_generation); |
| 449 | btrfs_set_stack_ref_objectid(&ref, owner); |
| 450 | btrfs_set_stack_ref_offset(&ref, owner_offset); |
| 451 | |
| 452 | hash = hash_extent_ref(root_objectid, ref_generation, owner, |
| 453 | owner_offset); |
| 454 | key.offset = hash; |
| 455 | key.objectid = bytenr; |
| 456 | key.type = BTRFS_EXTENT_REF_KEY; |
| 457 | |
| 458 | while (1) { |
| 459 | ret = btrfs_search_slot(trans, root, &key, path, |
| 460 | del ? -1 : 0, del); |
| 461 | if (ret < 0) |
| 462 | goto out; |
| 463 | leaf = path->nodes[0]; |
| 464 | if (ret != 0) { |
| 465 | u32 nritems = btrfs_header_nritems(leaf); |
| 466 | if (path->slots[0] >= nritems) { |
| 467 | ret2 = btrfs_next_leaf(root, path); |
| 468 | if (ret2) |
| 469 | goto out; |
| 470 | leaf = path->nodes[0]; |
| 471 | } |
| 472 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 473 | if (found_key.objectid != bytenr || |
| 474 | found_key.type != BTRFS_EXTENT_REF_KEY) |
| 475 | goto out; |
| 476 | key.offset = found_key.offset; |
| 477 | if (del) { |
| 478 | btrfs_release_path(root, path); |
| 479 | continue; |
| 480 | } |
| 481 | } |
| 482 | disk_ref = btrfs_item_ptr(path->nodes[0], |
| 483 | path->slots[0], |
| 484 | struct btrfs_extent_ref); |
| 485 | if (match_extent_ref(path->nodes[0], disk_ref, &ref)) { |
| 486 | ret = 0; |
| 487 | goto out; |
| 488 | } |
| 489 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 490 | key.offset = found_key.offset + 1; |
| 491 | btrfs_release_path(root, path); |
| 492 | } |
| 493 | out: |
| 494 | return ret; |
| 495 | } |
| 496 | |
| 497 | /* |
| 498 | * Back reference rules. Back refs have three main goals: |
| 499 | * |
| 500 | * 1) differentiate between all holders of references to an extent so that |
| 501 | * when a reference is dropped we can make sure it was a valid reference |
| 502 | * before freeing the extent. |
| 503 | * |
| 504 | * 2) Provide enough information to quickly find the holders of an extent |
| 505 | * if we notice a given block is corrupted or bad. |
| 506 | * |
| 507 | * 3) Make it easy to migrate blocks for FS shrinking or storage pool |
| 508 | * maintenance. This is actually the same as #2, but with a slightly |
| 509 | * different use case. |
| 510 | * |
| 511 | * File extents can be referenced by: |
| 512 | * |
| 513 | * - multiple snapshots, subvolumes, or different generations in one subvol |
| 514 | * - different files inside a single subvolume (in theory, not implemented yet) |
| 515 | * - different offsets inside a file (bookend extents in file.c) |
| 516 | * |
| 517 | * The extent ref structure has fields for: |
| 518 | * |
| 519 | * - Objectid of the subvolume root |
| 520 | * - Generation number of the tree holding the reference |
| 521 | * - objectid of the file holding the reference |
| 522 | * - offset in the file corresponding to the key holding the reference |
| 523 | * |
| 524 | * When a file extent is allocated the fields are filled in: |
| 525 | * (root_key.objectid, trans->transid, inode objectid, offset in file) |
| 526 | * |
| 527 | * When a leaf is cow'd new references are added for every file extent found |
| 528 | * in the leaf. It looks the same as the create case, but trans->transid |
| 529 | * will be different when the block is cow'd. |
| 530 | * |
| 531 | * (root_key.objectid, trans->transid, inode objectid, offset in file) |
| 532 | * |
| 533 | * When a file extent is removed either during snapshot deletion or file |
| 534 | * truncation, the corresponding back reference is found |
| 535 | * by searching for: |
| 536 | * |
| 537 | * (btrfs_header_owner(leaf), btrfs_header_generation(leaf), |
| 538 | * inode objectid, offset in file) |
| 539 | * |
| 540 | * Btree extents can be referenced by: |
| 541 | * |
| 542 | * - Different subvolumes |
| 543 | * - Different generations of the same subvolume |
| 544 | * |
| 545 | * Storing sufficient information for a full reverse mapping of a btree |
| 546 | * block would require storing the lowest key of the block in the backref, |
| 547 | * and it would require updating that lowest key either before write out or |
| 548 | * every time it changed. Instead, the objectid of the lowest key is stored |
| 549 | * along with the level of the tree block. This provides a hint |
| 550 | * about where in the btree the block can be found. Searches through the |
| 551 | * btree only need to look for a pointer to that block, so they stop one |
| 552 | * level higher than the level recorded in the backref. |
| 553 | * |
| 554 | * Some btrees do not do reference counting on their extents. These |
| 555 | * include the extent tree and the tree of tree roots. Backrefs for these |
| 556 | * trees always have a generation of zero. |
| 557 | * |
| 558 | * When a tree block is created, back references are inserted: |
| 559 | * |
| 560 | * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid) |
| 561 | * |
| 562 | * When a tree block is cow'd in a reference counted root, |
| 563 | * new back references are added for all the blocks it points to. |
| 564 | * These are of the form (trans->transid will have increased since creation): |
| 565 | * |
| 566 | * (root->root_key.objectid, trans->transid, level, lowest_key_objectid) |
| 567 | * |
| 568 | * Because the lowest_key_objectid and the level are just hints |
| 569 | * they are not used when backrefs are deleted. When a backref is deleted: |
| 570 | * |
| 571 | * if backref was for a tree root: |
| 572 | * root_objectid = root->root_key.objectid |
| 573 | * else |
| 574 | * root_objectid = btrfs_header_owner(parent) |
| 575 | * |
| 576 | * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0) |
| 577 | * |
| 578 | * Back Reference Key hashing: |
| 579 | * |
| 580 | * Back references have four fields, each 64 bits long. Unfortunately, |
| 581 | * This is hashed into a single 64 bit number and placed into the key offset. |
| 582 | * The key objectid corresponds to the first byte in the extent, and the |
| 583 | * key type is set to BTRFS_EXTENT_REF_KEY |
| 584 | */ |
| 585 | int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans, |
| 586 | struct btrfs_root *root, |
| 587 | struct btrfs_path *path, u64 bytenr, |
| 588 | u64 root_objectid, u64 ref_generation, |
| 589 | u64 owner, u64 owner_offset) |
| 590 | { |
| 591 | u64 hash; |
| 592 | struct btrfs_key key; |
| 593 | struct btrfs_extent_ref ref; |
| 594 | struct btrfs_extent_ref *disk_ref; |
| 595 | int ret; |
| 596 | |
| 597 | btrfs_set_stack_ref_root(&ref, root_objectid); |
| 598 | btrfs_set_stack_ref_generation(&ref, ref_generation); |
| 599 | btrfs_set_stack_ref_objectid(&ref, owner); |
| 600 | btrfs_set_stack_ref_offset(&ref, owner_offset); |
| 601 | |
| 602 | hash = hash_extent_ref(root_objectid, ref_generation, owner, |
| 603 | owner_offset); |
| 604 | key.offset = hash; |
| 605 | key.objectid = bytenr; |
| 606 | key.type = BTRFS_EXTENT_REF_KEY; |
| 607 | |
| 608 | ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref)); |
| 609 | while (ret == -EEXIST) { |
| 610 | disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 611 | struct btrfs_extent_ref); |
| 612 | if (match_extent_ref(path->nodes[0], disk_ref, &ref)) |
| 613 | goto out; |
| 614 | key.offset++; |
| 615 | btrfs_release_path(root, path); |
| 616 | ret = btrfs_insert_empty_item(trans, root, path, &key, |
| 617 | sizeof(ref)); |
| 618 | } |
| 619 | if (ret) |
| 620 | goto out; |
| 621 | disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 622 | struct btrfs_extent_ref); |
| 623 | write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref, |
| 624 | sizeof(ref)); |
| 625 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 626 | out: |
| 627 | btrfs_release_path(root, path); |
| 628 | return ret; |
| 629 | } |
| 630 | |
| 631 | int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, |
| 632 | struct btrfs_root *root, |
| 633 | u64 bytenr, u64 num_bytes, |
| 634 | u64 root_objectid, u64 ref_generation, |
| 635 | u64 owner, u64 owner_offset) |
| 636 | { |
| 637 | struct btrfs_path *path; |
| 638 | int ret; |
| 639 | struct btrfs_key key; |
| 640 | struct extent_buffer *l; |
| 641 | struct btrfs_extent_item *item; |
| 642 | u32 refs; |
| 643 | |
| 644 | WARN_ON(num_bytes < root->sectorsize); |
| 645 | path = btrfs_alloc_path(); |
| 646 | if (!path) |
| 647 | return -ENOMEM; |
| 648 | |
| 649 | path->reada = 0; |
| 650 | key.objectid = bytenr; |
| 651 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 652 | key.offset = num_bytes; |
| 653 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, |
| 654 | 0, 1); |
| 655 | if (ret < 0) |
| 656 | return ret; |
| 657 | if (ret != 0) { |
| 658 | BUG(); |
| 659 | } |
| 660 | BUG_ON(ret != 0); |
| 661 | l = path->nodes[0]; |
| 662 | item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); |
| 663 | refs = btrfs_extent_refs(l, item); |
| 664 | btrfs_set_extent_refs(l, item, refs + 1); |
| 665 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 666 | |
| 667 | btrfs_release_path(root->fs_info->extent_root, path); |
| 668 | |
| 669 | path->reada = 0; |
| 670 | ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root, |
| 671 | path, bytenr, root_objectid, |
| 672 | ref_generation, owner, owner_offset); |
| 673 | BUG_ON(ret); |
| 674 | finish_current_insert(trans, root->fs_info->extent_root); |
| 675 | del_pending_extents(trans, root->fs_info->extent_root); |
| 676 | |
| 677 | btrfs_free_path(path); |
| 678 | return 0; |
| 679 | } |
| 680 | |
| 681 | int btrfs_extent_post_op(struct btrfs_trans_handle *trans, |
| 682 | struct btrfs_root *root) |
| 683 | { |
| 684 | finish_current_insert(trans, root->fs_info->extent_root); |
| 685 | del_pending_extents(trans, root->fs_info->extent_root); |
| 686 | return 0; |
| 687 | } |
| 688 | |
| 689 | static int lookup_extent_ref(struct btrfs_trans_handle *trans, |
| 690 | struct btrfs_root *root, u64 bytenr, |
| 691 | u64 num_bytes, u32 *refs) |
| 692 | { |
| 693 | struct btrfs_path *path; |
| 694 | int ret; |
| 695 | struct btrfs_key key; |
| 696 | struct extent_buffer *l; |
| 697 | struct btrfs_extent_item *item; |
| 698 | |
| 699 | WARN_ON(num_bytes < root->sectorsize); |
| 700 | path = btrfs_alloc_path(); |
| 701 | path->reada = 0; |
| 702 | key.objectid = bytenr; |
| 703 | key.offset = num_bytes; |
| 704 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 705 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, |
| 706 | 0, 0); |
| 707 | if (ret < 0) |
| 708 | goto out; |
| 709 | if (ret != 0) { |
| 710 | btrfs_print_leaf(root, path->nodes[0]); |
| 711 | printk("failed to find block number %Lu\n", bytenr); |
| 712 | BUG(); |
| 713 | } |
| 714 | l = path->nodes[0]; |
| 715 | item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); |
| 716 | *refs = btrfs_extent_refs(l, item); |
| 717 | out: |
| 718 | btrfs_free_path(path); |
| 719 | return 0; |
| 720 | } |
| 721 | |
| 722 | u32 btrfs_count_snapshots_in_path(struct btrfs_root *root, |
| 723 | struct btrfs_path *count_path, |
| 724 | u64 first_extent) |
| 725 | { |
| 726 | struct btrfs_root *extent_root = root->fs_info->extent_root; |
| 727 | struct btrfs_path *path; |
| 728 | u64 bytenr; |
| 729 | u64 found_objectid; |
| 730 | u64 root_objectid = root->root_key.objectid; |
| 731 | u32 total_count = 0; |
| 732 | u32 cur_count; |
| 733 | u32 nritems; |
| 734 | int ret; |
| 735 | struct btrfs_key key; |
| 736 | struct btrfs_key found_key; |
| 737 | struct extent_buffer *l; |
| 738 | struct btrfs_extent_item *item; |
| 739 | struct btrfs_extent_ref *ref_item; |
| 740 | int level = -1; |
| 741 | |
| 742 | path = btrfs_alloc_path(); |
| 743 | again: |
| 744 | if (level == -1) |
| 745 | bytenr = first_extent; |
| 746 | else |
| 747 | bytenr = count_path->nodes[level]->start; |
| 748 | |
| 749 | cur_count = 0; |
| 750 | key.objectid = bytenr; |
| 751 | key.offset = 0; |
| 752 | |
| 753 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 754 | ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); |
| 755 | if (ret < 0) |
| 756 | goto out; |
| 757 | BUG_ON(ret == 0); |
| 758 | |
| 759 | l = path->nodes[0]; |
| 760 | btrfs_item_key_to_cpu(l, &found_key, path->slots[0]); |
| 761 | |
| 762 | if (found_key.objectid != bytenr || |
| 763 | found_key.type != BTRFS_EXTENT_ITEM_KEY) { |
| 764 | goto out; |
| 765 | } |
| 766 | |
| 767 | item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); |
| 768 | while (1) { |
| 769 | l = path->nodes[0]; |
| 770 | nritems = btrfs_header_nritems(l); |
| 771 | if (path->slots[0] >= nritems) { |
| 772 | ret = btrfs_next_leaf(extent_root, path); |
| 773 | if (ret == 0) |
| 774 | continue; |
| 775 | break; |
| 776 | } |
| 777 | btrfs_item_key_to_cpu(l, &found_key, path->slots[0]); |
| 778 | if (found_key.objectid != bytenr) |
| 779 | break; |
| 780 | |
| 781 | if (found_key.type != BTRFS_EXTENT_REF_KEY) { |
| 782 | path->slots[0]++; |
| 783 | continue; |
| 784 | } |
| 785 | |
| 786 | cur_count++; |
| 787 | ref_item = btrfs_item_ptr(l, path->slots[0], |
| 788 | struct btrfs_extent_ref); |
| 789 | found_objectid = btrfs_ref_root(l, ref_item); |
| 790 | |
| 791 | if (found_objectid != root_objectid) { |
| 792 | total_count = 2; |
| 793 | goto out; |
| 794 | } |
| 795 | total_count = 1; |
| 796 | path->slots[0]++; |
| 797 | } |
| 798 | if (cur_count == 0) { |
| 799 | total_count = 0; |
| 800 | goto out; |
| 801 | } |
| 802 | if (level >= 0 && root->node == count_path->nodes[level]) |
| 803 | goto out; |
| 804 | level++; |
| 805 | btrfs_release_path(root, path); |
| 806 | goto again; |
| 807 | |
| 808 | out: |
| 809 | btrfs_free_path(path); |
| 810 | return total_count; |
| 811 | } |
| 812 | int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, |
| 813 | struct btrfs_root *root, u64 owner_objectid) |
| 814 | { |
| 815 | u64 generation; |
| 816 | u64 key_objectid; |
| 817 | u64 level; |
| 818 | u32 nritems; |
| 819 | struct btrfs_disk_key disk_key; |
| 820 | |
| 821 | level = btrfs_header_level(root->node); |
| 822 | generation = trans->transid; |
| 823 | nritems = btrfs_header_nritems(root->node); |
| 824 | if (nritems > 0) { |
| 825 | if (level == 0) |
| 826 | btrfs_item_key(root->node, &disk_key, 0); |
| 827 | else |
| 828 | btrfs_node_key(root->node, &disk_key, 0); |
| 829 | key_objectid = btrfs_disk_key_objectid(&disk_key); |
| 830 | } else { |
| 831 | key_objectid = 0; |
| 832 | } |
| 833 | return btrfs_inc_extent_ref(trans, root, root->node->start, |
| 834 | root->node->len, owner_objectid, |
| 835 | generation, level, key_objectid); |
| 836 | } |
| 837 | |
| 838 | int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
| 839 | struct extent_buffer *buf) |
| 840 | { |
| 841 | u64 bytenr; |
| 842 | u32 nritems; |
| 843 | struct btrfs_key key; |
| 844 | struct btrfs_file_extent_item *fi; |
| 845 | int i; |
| 846 | int level; |
| 847 | int ret; |
| 848 | int faili; |
| 849 | |
| 850 | if (!root->ref_cows) |
| 851 | return 0; |
| 852 | |
| 853 | level = btrfs_header_level(buf); |
| 854 | nritems = btrfs_header_nritems(buf); |
| 855 | for (i = 0; i < nritems; i++) { |
| 856 | if (level == 0) { |
| 857 | u64 disk_bytenr; |
| 858 | btrfs_item_key_to_cpu(buf, &key, i); |
| 859 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) |
| 860 | continue; |
| 861 | fi = btrfs_item_ptr(buf, i, |
| 862 | struct btrfs_file_extent_item); |
| 863 | if (btrfs_file_extent_type(buf, fi) == |
| 864 | BTRFS_FILE_EXTENT_INLINE) |
| 865 | continue; |
| 866 | disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); |
| 867 | if (disk_bytenr == 0) |
| 868 | continue; |
| 869 | ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, |
| 870 | btrfs_file_extent_disk_num_bytes(buf, fi), |
| 871 | root->root_key.objectid, trans->transid, |
| 872 | key.objectid, key.offset); |
| 873 | if (ret) { |
| 874 | faili = i; |
| 875 | goto fail; |
| 876 | } |
| 877 | } else { |
| 878 | bytenr = btrfs_node_blockptr(buf, i); |
| 879 | btrfs_node_key_to_cpu(buf, &key, i); |
| 880 | ret = btrfs_inc_extent_ref(trans, root, bytenr, |
| 881 | btrfs_level_size(root, level - 1), |
| 882 | root->root_key.objectid, |
| 883 | trans->transid, |
| 884 | level - 1, key.objectid); |
| 885 | if (ret) { |
| 886 | faili = i; |
| 887 | goto fail; |
| 888 | } |
| 889 | } |
| 890 | } |
| 891 | return 0; |
| 892 | fail: |
| 893 | WARN_ON(1); |
| 894 | #if 0 |
| 895 | for (i =0; i < faili; i++) { |
| 896 | if (level == 0) { |
| 897 | u64 disk_bytenr; |
| 898 | btrfs_item_key_to_cpu(buf, &key, i); |
| 899 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) |
| 900 | continue; |
| 901 | fi = btrfs_item_ptr(buf, i, |
| 902 | struct btrfs_file_extent_item); |
| 903 | if (btrfs_file_extent_type(buf, fi) == |
| 904 | BTRFS_FILE_EXTENT_INLINE) |
| 905 | continue; |
| 906 | disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); |
| 907 | if (disk_bytenr == 0) |
| 908 | continue; |
| 909 | err = btrfs_free_extent(trans, root, disk_bytenr, |
| 910 | btrfs_file_extent_disk_num_bytes(buf, |
| 911 | fi), 0); |
| 912 | BUG_ON(err); |
| 913 | } else { |
| 914 | bytenr = btrfs_node_blockptr(buf, i); |
| 915 | err = btrfs_free_extent(trans, root, bytenr, |
| 916 | btrfs_level_size(root, level - 1), 0); |
| 917 | BUG_ON(err); |
| 918 | } |
| 919 | } |
| 920 | #endif |
| 921 | return ret; |
| 922 | } |
| 923 | |
| 924 | static int write_one_cache_group(struct btrfs_trans_handle *trans, |
| 925 | struct btrfs_root *root, |
| 926 | struct btrfs_path *path, |
| 927 | struct btrfs_block_group_cache *cache) |
| 928 | { |
| 929 | int ret; |
| 930 | int pending_ret; |
| 931 | struct btrfs_root *extent_root = root->fs_info->extent_root; |
| 932 | unsigned long bi; |
| 933 | struct extent_buffer *leaf; |
| 934 | |
| 935 | ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); |
| 936 | if (ret < 0) |
| 937 | goto fail; |
| 938 | BUG_ON(ret); |
| 939 | |
| 940 | leaf = path->nodes[0]; |
| 941 | bi = btrfs_item_ptr_offset(leaf, path->slots[0]); |
| 942 | write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item)); |
| 943 | btrfs_mark_buffer_dirty(leaf); |
| 944 | btrfs_release_path(extent_root, path); |
| 945 | fail: |
| 946 | finish_current_insert(trans, extent_root); |
| 947 | pending_ret = del_pending_extents(trans, extent_root); |
| 948 | if (ret) |
| 949 | return ret; |
| 950 | if (pending_ret) |
| 951 | return pending_ret; |
| 952 | return 0; |
| 953 | |
| 954 | } |
| 955 | |
| 956 | int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, |
| 957 | struct btrfs_root *root) |
| 958 | { |
| 959 | struct extent_io_tree *block_group_cache; |
| 960 | struct btrfs_block_group_cache *cache; |
| 961 | int ret; |
| 962 | int err = 0; |
| 963 | int werr = 0; |
| 964 | struct btrfs_path *path; |
| 965 | u64 last = 0; |
| 966 | u64 start; |
| 967 | u64 end; |
| 968 | u64 ptr; |
| 969 | |
| 970 | block_group_cache = &root->fs_info->block_group_cache; |
| 971 | path = btrfs_alloc_path(); |
| 972 | if (!path) |
| 973 | return -ENOMEM; |
| 974 | |
| 975 | while(1) { |
| 976 | ret = find_first_extent_bit(block_group_cache, last, |
| 977 | &start, &end, BLOCK_GROUP_DIRTY); |
| 978 | if (ret) |
| 979 | break; |
| 980 | |
| 981 | last = end + 1; |
| 982 | ret = get_state_private(block_group_cache, start, &ptr); |
| 983 | if (ret) |
| 984 | break; |
| 985 | |
| 986 | cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; |
| 987 | err = write_one_cache_group(trans, root, |
| 988 | path, cache); |
| 989 | /* |
| 990 | * if we fail to write the cache group, we want |
| 991 | * to keep it marked dirty in hopes that a later |
| 992 | * write will work |
| 993 | */ |
| 994 | if (err) { |
| 995 | werr = err; |
| 996 | continue; |
| 997 | } |
| 998 | clear_extent_bits(block_group_cache, start, end, |
| 999 | BLOCK_GROUP_DIRTY, GFP_NOFS); |
| 1000 | } |
| 1001 | btrfs_free_path(path); |
| 1002 | return werr; |
| 1003 | } |
| 1004 | |
| 1005 | static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, |
| 1006 | u64 flags) |
| 1007 | { |
| 1008 | struct list_head *head = &info->space_info; |
| 1009 | struct list_head *cur; |
| 1010 | struct btrfs_space_info *found; |
| 1011 | list_for_each(cur, head) { |
| 1012 | found = list_entry(cur, struct btrfs_space_info, list); |
| 1013 | if (found->flags == flags) |
| 1014 | return found; |
| 1015 | } |
| 1016 | return NULL; |
| 1017 | |
| 1018 | } |
| 1019 | |
| 1020 | static int update_space_info(struct btrfs_fs_info *info, u64 flags, |
| 1021 | u64 total_bytes, u64 bytes_used, |
| 1022 | struct btrfs_space_info **space_info) |
| 1023 | { |
| 1024 | struct btrfs_space_info *found; |
| 1025 | |
| 1026 | found = __find_space_info(info, flags); |
| 1027 | if (found) { |
| 1028 | found->total_bytes += total_bytes; |
| 1029 | found->bytes_used += bytes_used; |
| 1030 | WARN_ON(found->total_bytes < found->bytes_used); |
| 1031 | *space_info = found; |
| 1032 | return 0; |
| 1033 | } |
| 1034 | found = kmalloc(sizeof(*found), GFP_NOFS); |
| 1035 | if (!found) |
| 1036 | return -ENOMEM; |
| 1037 | |
| 1038 | list_add(&found->list, &info->space_info); |
| 1039 | found->flags = flags; |
| 1040 | found->total_bytes = total_bytes; |
| 1041 | found->bytes_used = bytes_used; |
| 1042 | found->bytes_pinned = 0; |
| 1043 | found->full = 0; |
| 1044 | *space_info = found; |
| 1045 | return 0; |
| 1046 | } |
| 1047 | |
| 1048 | static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) |
| 1049 | { |
| 1050 | u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 | |
| 1051 | BTRFS_BLOCK_GROUP_RAID1); |
| 1052 | if (extra_flags) { |
| 1053 | if (flags & BTRFS_BLOCK_GROUP_DATA) |
| 1054 | fs_info->avail_data_alloc_bits |= extra_flags; |
| 1055 | if (flags & BTRFS_BLOCK_GROUP_METADATA) |
| 1056 | fs_info->avail_metadata_alloc_bits |= extra_flags; |
| 1057 | if (flags & BTRFS_BLOCK_GROUP_SYSTEM) |
| 1058 | fs_info->avail_system_alloc_bits |= extra_flags; |
| 1059 | } |
| 1060 | } |
| 1061 | |
| 1062 | static int do_chunk_alloc(struct btrfs_trans_handle *trans, |
| 1063 | struct btrfs_root *extent_root, u64 alloc_bytes, |
| 1064 | u64 flags) |
| 1065 | { |
| 1066 | struct btrfs_space_info *space_info; |
| 1067 | u64 thresh; |
| 1068 | u64 start; |
| 1069 | u64 num_bytes; |
| 1070 | int ret; |
| 1071 | |
| 1072 | space_info = __find_space_info(extent_root->fs_info, flags); |
| 1073 | if (!space_info) { |
| 1074 | ret = update_space_info(extent_root->fs_info, flags, |
| 1075 | 0, 0, &space_info); |
| 1076 | BUG_ON(ret); |
| 1077 | } |
| 1078 | BUG_ON(!space_info); |
| 1079 | |
| 1080 | if (space_info->full) |
| 1081 | return 0; |
| 1082 | |
| 1083 | thresh = div_factor(space_info->total_bytes, 6); |
| 1084 | if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) < |
| 1085 | thresh) |
| 1086 | return 0; |
| 1087 | |
| 1088 | ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags); |
| 1089 | if (ret == -ENOSPC) { |
| 1090 | printk("space info full %Lu\n", flags); |
| 1091 | space_info->full = 1; |
| 1092 | return 0; |
| 1093 | } |
| 1094 | |
| 1095 | BUG_ON(ret); |
| 1096 | |
| 1097 | ret = btrfs_make_block_group(trans, extent_root, 0, flags, |
| 1098 | extent_root->fs_info->chunk_root->root_key.objectid, |
| 1099 | start, num_bytes); |
| 1100 | BUG_ON(ret); |
| 1101 | |
| 1102 | set_avail_alloc_bits(extent_root->fs_info, flags); |
| 1103 | return 0; |
| 1104 | } |
| 1105 | |
| 1106 | static int update_block_group(struct btrfs_trans_handle *trans, |
| 1107 | struct btrfs_root *root, |
| 1108 | u64 bytenr, u64 num_bytes, int alloc, |
| 1109 | int mark_free) |
| 1110 | { |
| 1111 | struct btrfs_block_group_cache *cache; |
| 1112 | struct btrfs_fs_info *info = root->fs_info; |
| 1113 | u64 total = num_bytes; |
| 1114 | u64 old_val; |
| 1115 | u64 byte_in_group; |
| 1116 | u64 start; |
| 1117 | u64 end; |
| 1118 | |
| 1119 | while(total) { |
| 1120 | cache = btrfs_lookup_block_group(info, bytenr); |
| 1121 | if (!cache) { |
| 1122 | return -1; |
| 1123 | } |
| 1124 | byte_in_group = bytenr - cache->key.objectid; |
| 1125 | WARN_ON(byte_in_group > cache->key.offset); |
| 1126 | start = cache->key.objectid; |
| 1127 | end = start + cache->key.offset - 1; |
| 1128 | set_extent_bits(&info->block_group_cache, start, end, |
| 1129 | BLOCK_GROUP_DIRTY, GFP_NOFS); |
| 1130 | |
| 1131 | old_val = btrfs_block_group_used(&cache->item); |
| 1132 | num_bytes = min(total, cache->key.offset - byte_in_group); |
| 1133 | if (alloc) { |
| 1134 | old_val += num_bytes; |
| 1135 | cache->space_info->bytes_used += num_bytes; |
| 1136 | } else { |
| 1137 | old_val -= num_bytes; |
| 1138 | cache->space_info->bytes_used -= num_bytes; |
| 1139 | if (mark_free) { |
| 1140 | set_extent_dirty(&info->free_space_cache, |
| 1141 | bytenr, bytenr + num_bytes - 1, |
| 1142 | GFP_NOFS); |
| 1143 | } |
| 1144 | } |
| 1145 | btrfs_set_block_group_used(&cache->item, old_val); |
| 1146 | total -= num_bytes; |
| 1147 | bytenr += num_bytes; |
| 1148 | } |
| 1149 | return 0; |
| 1150 | } |
| 1151 | |
| 1152 | static int update_pinned_extents(struct btrfs_root *root, |
| 1153 | u64 bytenr, u64 num, int pin) |
| 1154 | { |
| 1155 | u64 len; |
| 1156 | struct btrfs_block_group_cache *cache; |
| 1157 | struct btrfs_fs_info *fs_info = root->fs_info; |
| 1158 | |
| 1159 | if (pin) { |
| 1160 | set_extent_dirty(&fs_info->pinned_extents, |
| 1161 | bytenr, bytenr + num - 1, GFP_NOFS); |
| 1162 | } else { |
| 1163 | clear_extent_dirty(&fs_info->pinned_extents, |
| 1164 | bytenr, bytenr + num - 1, GFP_NOFS); |
| 1165 | } |
| 1166 | while (num > 0) { |
| 1167 | cache = btrfs_lookup_block_group(fs_info, bytenr); |
| 1168 | WARN_ON(!cache); |
| 1169 | len = min(num, cache->key.offset - |
| 1170 | (bytenr - cache->key.objectid)); |
| 1171 | if (pin) { |
| 1172 | cache->pinned += len; |
| 1173 | cache->space_info->bytes_pinned += len; |
| 1174 | fs_info->total_pinned += len; |
| 1175 | } else { |
| 1176 | cache->pinned -= len; |
| 1177 | cache->space_info->bytes_pinned -= len; |
| 1178 | fs_info->total_pinned -= len; |
| 1179 | } |
| 1180 | bytenr += len; |
| 1181 | num -= len; |
| 1182 | } |
| 1183 | return 0; |
| 1184 | } |
| 1185 | |
| 1186 | int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy) |
| 1187 | { |
| 1188 | u64 last = 0; |
| 1189 | u64 start; |
| 1190 | u64 end; |
| 1191 | struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents; |
| 1192 | int ret; |
| 1193 | |
| 1194 | while(1) { |
| 1195 | ret = find_first_extent_bit(pinned_extents, last, |
| 1196 | &start, &end, EXTENT_DIRTY); |
| 1197 | if (ret) |
| 1198 | break; |
| 1199 | set_extent_dirty(copy, start, end, GFP_NOFS); |
| 1200 | last = end + 1; |
| 1201 | } |
| 1202 | return 0; |
| 1203 | } |
| 1204 | |
| 1205 | int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, |
| 1206 | struct btrfs_root *root, |
| 1207 | struct extent_io_tree *unpin) |
| 1208 | { |
| 1209 | u64 start; |
| 1210 | u64 end; |
| 1211 | int ret; |
| 1212 | struct extent_io_tree *free_space_cache; |
| 1213 | free_space_cache = &root->fs_info->free_space_cache; |
| 1214 | |
| 1215 | while(1) { |
| 1216 | ret = find_first_extent_bit(unpin, 0, &start, &end, |
| 1217 | EXTENT_DIRTY); |
| 1218 | if (ret) |
| 1219 | break; |
| 1220 | update_pinned_extents(root, start, end + 1 - start, 0); |
| 1221 | clear_extent_dirty(unpin, start, end, GFP_NOFS); |
| 1222 | set_extent_dirty(free_space_cache, start, end, GFP_NOFS); |
| 1223 | } |
| 1224 | return 0; |
| 1225 | } |
| 1226 | |
| 1227 | static int finish_current_insert(struct btrfs_trans_handle *trans, |
| 1228 | struct btrfs_root *extent_root) |
| 1229 | { |
| 1230 | u64 start; |
| 1231 | u64 end; |
| 1232 | struct btrfs_fs_info *info = extent_root->fs_info; |
| 1233 | struct extent_buffer *eb; |
| 1234 | struct btrfs_path *path; |
| 1235 | struct btrfs_key ins; |
| 1236 | struct btrfs_disk_key first; |
| 1237 | struct btrfs_extent_item extent_item; |
| 1238 | int ret; |
| 1239 | int level; |
| 1240 | int err = 0; |
| 1241 | |
| 1242 | btrfs_set_stack_extent_refs(&extent_item, 1); |
| 1243 | btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY); |
| 1244 | path = btrfs_alloc_path(); |
| 1245 | |
| 1246 | while(1) { |
| 1247 | ret = find_first_extent_bit(&info->extent_ins, 0, &start, |
| 1248 | &end, EXTENT_LOCKED); |
| 1249 | if (ret) |
| 1250 | break; |
| 1251 | |
| 1252 | ins.objectid = start; |
| 1253 | ins.offset = end + 1 - start; |
| 1254 | err = btrfs_insert_item(trans, extent_root, &ins, |
| 1255 | &extent_item, sizeof(extent_item)); |
| 1256 | clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED, |
| 1257 | GFP_NOFS); |
| 1258 | eb = read_tree_block(extent_root, ins.objectid, ins.offset); |
| 1259 | level = btrfs_header_level(eb); |
| 1260 | if (level == 0) { |
| 1261 | btrfs_item_key(eb, &first, 0); |
| 1262 | } else { |
| 1263 | btrfs_node_key(eb, &first, 0); |
| 1264 | } |
| 1265 | err = btrfs_insert_extent_backref(trans, extent_root, path, |
| 1266 | start, extent_root->root_key.objectid, |
| 1267 | 0, level, |
| 1268 | btrfs_disk_key_objectid(&first)); |
| 1269 | BUG_ON(err); |
| 1270 | free_extent_buffer(eb); |
| 1271 | } |
| 1272 | btrfs_free_path(path); |
| 1273 | return 0; |
| 1274 | } |
| 1275 | |
| 1276 | static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes, |
| 1277 | int pending) |
| 1278 | { |
| 1279 | int err = 0; |
| 1280 | struct extent_buffer *buf; |
| 1281 | |
| 1282 | if (!pending) { |
| 1283 | buf = btrfs_find_tree_block(root, bytenr, num_bytes); |
| 1284 | if (buf) { |
| 1285 | if (btrfs_buffer_uptodate(buf)) { |
| 1286 | u64 transid = |
| 1287 | root->fs_info->running_transaction->transid; |
| 1288 | u64 header_transid = |
| 1289 | btrfs_header_generation(buf); |
| 1290 | if (header_transid == transid) { |
| 1291 | clean_tree_block(NULL, root, buf); |
| 1292 | free_extent_buffer(buf); |
| 1293 | return 1; |
| 1294 | } |
| 1295 | } |
| 1296 | free_extent_buffer(buf); |
| 1297 | } |
| 1298 | update_pinned_extents(root, bytenr, num_bytes, 1); |
| 1299 | } else { |
| 1300 | set_extent_bits(&root->fs_info->pending_del, |
| 1301 | bytenr, bytenr + num_bytes - 1, |
| 1302 | EXTENT_LOCKED, GFP_NOFS); |
| 1303 | } |
| 1304 | BUG_ON(err < 0); |
| 1305 | return 0; |
| 1306 | } |
| 1307 | |
| 1308 | /* |
| 1309 | * remove an extent from the root, returns 0 on success |
| 1310 | */ |
| 1311 | static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 1312 | *root, u64 bytenr, u64 num_bytes, |
| 1313 | u64 root_objectid, u64 ref_generation, |
| 1314 | u64 owner_objectid, u64 owner_offset, int pin, |
| 1315 | int mark_free) |
| 1316 | { |
| 1317 | struct btrfs_path *path; |
| 1318 | struct btrfs_key key; |
| 1319 | struct btrfs_fs_info *info = root->fs_info; |
| 1320 | struct btrfs_root *extent_root = info->extent_root; |
| 1321 | struct extent_buffer *leaf; |
| 1322 | int ret; |
| 1323 | int extent_slot = 0; |
| 1324 | int found_extent = 0; |
| 1325 | int num_to_del = 1; |
| 1326 | struct btrfs_extent_item *ei; |
| 1327 | u32 refs; |
| 1328 | |
| 1329 | key.objectid = bytenr; |
| 1330 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 1331 | key.offset = num_bytes; |
| 1332 | path = btrfs_alloc_path(); |
| 1333 | if (!path) |
| 1334 | return -ENOMEM; |
| 1335 | |
| 1336 | path->reada = 0; |
| 1337 | ret = lookup_extent_backref(trans, extent_root, path, |
| 1338 | bytenr, root_objectid, |
| 1339 | ref_generation, |
| 1340 | owner_objectid, owner_offset, 1); |
| 1341 | if (ret == 0) { |
| 1342 | struct btrfs_key found_key; |
| 1343 | extent_slot = path->slots[0]; |
| 1344 | while(extent_slot > 0) { |
| 1345 | extent_slot--; |
| 1346 | btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| 1347 | extent_slot); |
| 1348 | if (found_key.objectid != bytenr) |
| 1349 | break; |
| 1350 | if (found_key.type == BTRFS_EXTENT_ITEM_KEY && |
| 1351 | found_key.offset == num_bytes) { |
| 1352 | found_extent = 1; |
| 1353 | break; |
| 1354 | } |
| 1355 | if (path->slots[0] - extent_slot > 5) |
| 1356 | break; |
| 1357 | } |
| 1358 | if (!found_extent) |
| 1359 | ret = btrfs_del_item(trans, extent_root, path); |
| 1360 | } else { |
| 1361 | btrfs_print_leaf(extent_root, path->nodes[0]); |
| 1362 | WARN_ON(1); |
| 1363 | printk("Unable to find ref byte nr %Lu root %Lu " |
| 1364 | " gen %Lu owner %Lu offset %Lu\n", bytenr, |
| 1365 | root_objectid, ref_generation, owner_objectid, |
| 1366 | owner_offset); |
| 1367 | } |
| 1368 | if (!found_extent) { |
| 1369 | btrfs_release_path(extent_root, path); |
| 1370 | ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); |
| 1371 | if (ret < 0) |
| 1372 | return ret; |
| 1373 | BUG_ON(ret); |
| 1374 | extent_slot = path->slots[0]; |
| 1375 | } |
| 1376 | |
| 1377 | leaf = path->nodes[0]; |
| 1378 | ei = btrfs_item_ptr(leaf, extent_slot, |
| 1379 | struct btrfs_extent_item); |
| 1380 | refs = btrfs_extent_refs(leaf, ei); |
| 1381 | BUG_ON(refs == 0); |
| 1382 | refs -= 1; |
| 1383 | btrfs_set_extent_refs(leaf, ei, refs); |
| 1384 | |
| 1385 | btrfs_mark_buffer_dirty(leaf); |
| 1386 | |
| 1387 | if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) { |
| 1388 | /* if the back ref and the extent are next to each other |
| 1389 | * they get deleted below in one shot |
| 1390 | */ |
| 1391 | path->slots[0] = extent_slot; |
| 1392 | num_to_del = 2; |
| 1393 | } else if (found_extent) { |
| 1394 | /* otherwise delete the extent back ref */ |
| 1395 | ret = btrfs_del_item(trans, extent_root, path); |
| 1396 | BUG_ON(ret); |
| 1397 | /* if refs are 0, we need to setup the path for deletion */ |
| 1398 | if (refs == 0) { |
| 1399 | btrfs_release_path(extent_root, path); |
| 1400 | ret = btrfs_search_slot(trans, extent_root, &key, path, |
| 1401 | -1, 1); |
| 1402 | if (ret < 0) |
| 1403 | return ret; |
| 1404 | BUG_ON(ret); |
| 1405 | } |
| 1406 | } |
| 1407 | |
| 1408 | if (refs == 0) { |
| 1409 | u64 super_used; |
| 1410 | u64 root_used; |
| 1411 | |
| 1412 | if (pin) { |
| 1413 | ret = pin_down_bytes(root, bytenr, num_bytes, 0); |
| 1414 | if (ret > 0) |
| 1415 | mark_free = 1; |
| 1416 | BUG_ON(ret < 0); |
| 1417 | } |
| 1418 | |
| 1419 | /* block accounting for super block */ |
| 1420 | super_used = btrfs_super_bytes_used(&info->super_copy); |
| 1421 | btrfs_set_super_bytes_used(&info->super_copy, |
| 1422 | super_used - num_bytes); |
| 1423 | |
| 1424 | /* block accounting for root item */ |
| 1425 | root_used = btrfs_root_used(&root->root_item); |
| 1426 | btrfs_set_root_used(&root->root_item, |
| 1427 | root_used - num_bytes); |
| 1428 | ret = btrfs_del_items(trans, extent_root, path, path->slots[0], |
| 1429 | num_to_del); |
| 1430 | if (ret) { |
| 1431 | return ret; |
| 1432 | } |
| 1433 | ret = update_block_group(trans, root, bytenr, num_bytes, 0, |
| 1434 | mark_free); |
| 1435 | BUG_ON(ret); |
| 1436 | } |
| 1437 | btrfs_free_path(path); |
| 1438 | finish_current_insert(trans, extent_root); |
| 1439 | return ret; |
| 1440 | } |
| 1441 | |
| 1442 | /* |
| 1443 | * find all the blocks marked as pending in the radix tree and remove |
| 1444 | * them from the extent map |
| 1445 | */ |
| 1446 | static int del_pending_extents(struct btrfs_trans_handle *trans, struct |
| 1447 | btrfs_root *extent_root) |
| 1448 | { |
| 1449 | int ret; |
| 1450 | int err = 0; |
| 1451 | u64 start; |
| 1452 | u64 end; |
| 1453 | struct extent_io_tree *pending_del; |
| 1454 | struct extent_io_tree *pinned_extents; |
| 1455 | |
| 1456 | pending_del = &extent_root->fs_info->pending_del; |
| 1457 | pinned_extents = &extent_root->fs_info->pinned_extents; |
| 1458 | |
| 1459 | while(1) { |
| 1460 | ret = find_first_extent_bit(pending_del, 0, &start, &end, |
| 1461 | EXTENT_LOCKED); |
| 1462 | if (ret) |
| 1463 | break; |
| 1464 | update_pinned_extents(extent_root, start, end + 1 - start, 1); |
| 1465 | clear_extent_bits(pending_del, start, end, EXTENT_LOCKED, |
| 1466 | GFP_NOFS); |
| 1467 | ret = __free_extent(trans, extent_root, |
| 1468 | start, end + 1 - start, |
| 1469 | extent_root->root_key.objectid, |
| 1470 | 0, 0, 0, 0, 0); |
| 1471 | if (ret) |
| 1472 | err = ret; |
| 1473 | } |
| 1474 | return err; |
| 1475 | } |
| 1476 | |
| 1477 | /* |
| 1478 | * remove an extent from the root, returns 0 on success |
| 1479 | */ |
| 1480 | int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 1481 | *root, u64 bytenr, u64 num_bytes, |
| 1482 | u64 root_objectid, u64 ref_generation, |
| 1483 | u64 owner_objectid, u64 owner_offset, int pin) |
| 1484 | { |
| 1485 | struct btrfs_root *extent_root = root->fs_info->extent_root; |
| 1486 | int pending_ret; |
| 1487 | int ret; |
| 1488 | |
| 1489 | WARN_ON(num_bytes < root->sectorsize); |
| 1490 | if (!root->ref_cows) |
| 1491 | ref_generation = 0; |
| 1492 | |
| 1493 | if (root == extent_root) { |
| 1494 | pin_down_bytes(root, bytenr, num_bytes, 1); |
| 1495 | return 0; |
| 1496 | } |
| 1497 | ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid, |
| 1498 | ref_generation, owner_objectid, owner_offset, |
| 1499 | pin, pin == 0); |
| 1500 | pending_ret = del_pending_extents(trans, root->fs_info->extent_root); |
| 1501 | return ret ? ret : pending_ret; |
| 1502 | } |
| 1503 | |
| 1504 | static u64 stripe_align(struct btrfs_root *root, u64 val) |
| 1505 | { |
| 1506 | u64 mask = ((u64)root->stripesize - 1); |
| 1507 | u64 ret = (val + mask) & ~mask; |
| 1508 | return ret; |
| 1509 | } |
| 1510 | |
| 1511 | /* |
| 1512 | * walks the btree of allocated extents and find a hole of a given size. |
| 1513 | * The key ins is changed to record the hole: |
| 1514 | * ins->objectid == block start |
| 1515 | * ins->flags = BTRFS_EXTENT_ITEM_KEY |
| 1516 | * ins->offset == number of blocks |
| 1517 | * Any available blocks before search_start are skipped. |
| 1518 | */ |
| 1519 | static int noinline find_free_extent(struct btrfs_trans_handle *trans, |
| 1520 | struct btrfs_root *orig_root, |
| 1521 | u64 num_bytes, u64 empty_size, |
| 1522 | u64 search_start, u64 search_end, |
| 1523 | u64 hint_byte, struct btrfs_key *ins, |
| 1524 | u64 exclude_start, u64 exclude_nr, |
| 1525 | int data) |
| 1526 | { |
| 1527 | int ret; |
| 1528 | u64 orig_search_start = search_start; |
| 1529 | struct btrfs_root * root = orig_root->fs_info->extent_root; |
| 1530 | struct btrfs_fs_info *info = root->fs_info; |
| 1531 | u64 total_needed = num_bytes; |
| 1532 | u64 *last_ptr = NULL; |
| 1533 | struct btrfs_block_group_cache *block_group; |
| 1534 | int full_scan = 0; |
| 1535 | int wrapped = 0; |
| 1536 | int empty_cluster = 2 * 1024 * 1024; |
| 1537 | |
| 1538 | WARN_ON(num_bytes < root->sectorsize); |
| 1539 | btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); |
| 1540 | |
| 1541 | if (data & BTRFS_BLOCK_GROUP_METADATA) { |
| 1542 | last_ptr = &root->fs_info->last_alloc; |
| 1543 | empty_cluster = 256 * 1024; |
| 1544 | } |
| 1545 | |
| 1546 | if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) { |
| 1547 | last_ptr = &root->fs_info->last_data_alloc; |
| 1548 | } |
| 1549 | |
| 1550 | if (last_ptr) { |
| 1551 | if (*last_ptr) |
| 1552 | hint_byte = *last_ptr; |
| 1553 | else { |
| 1554 | empty_size += empty_cluster; |
| 1555 | } |
| 1556 | } |
| 1557 | |
| 1558 | if (search_end == (u64)-1) |
| 1559 | search_end = btrfs_super_total_bytes(&info->super_copy); |
| 1560 | |
| 1561 | if (hint_byte) { |
| 1562 | block_group = btrfs_lookup_block_group(info, hint_byte); |
| 1563 | if (!block_group) |
| 1564 | hint_byte = search_start; |
| 1565 | block_group = btrfs_find_block_group(root, block_group, |
| 1566 | hint_byte, data, 1); |
| 1567 | if (last_ptr && *last_ptr == 0 && block_group) |
| 1568 | hint_byte = block_group->key.objectid; |
| 1569 | } else { |
| 1570 | block_group = btrfs_find_block_group(root, |
| 1571 | trans->block_group, |
| 1572 | search_start, data, 1); |
| 1573 | } |
| 1574 | search_start = max(search_start, hint_byte); |
| 1575 | |
| 1576 | total_needed += empty_size; |
| 1577 | |
| 1578 | check_failed: |
| 1579 | if (!block_group) { |
| 1580 | block_group = btrfs_lookup_block_group(info, search_start); |
| 1581 | if (!block_group) |
| 1582 | block_group = btrfs_lookup_block_group(info, |
| 1583 | orig_search_start); |
| 1584 | } |
| 1585 | ret = find_search_start(root, &block_group, &search_start, |
| 1586 | total_needed, data); |
| 1587 | if (ret == -ENOSPC && last_ptr && *last_ptr) { |
| 1588 | *last_ptr = 0; |
| 1589 | block_group = btrfs_lookup_block_group(info, |
| 1590 | orig_search_start); |
| 1591 | search_start = orig_search_start; |
| 1592 | ret = find_search_start(root, &block_group, &search_start, |
| 1593 | total_needed, data); |
| 1594 | } |
| 1595 | if (ret == -ENOSPC) |
| 1596 | goto enospc; |
| 1597 | if (ret) |
| 1598 | goto error; |
| 1599 | |
| 1600 | if (last_ptr && *last_ptr && search_start != *last_ptr) { |
| 1601 | *last_ptr = 0; |
| 1602 | if (!empty_size) { |
| 1603 | empty_size += empty_cluster; |
| 1604 | total_needed += empty_size; |
| 1605 | } |
| 1606 | block_group = btrfs_lookup_block_group(info, |
| 1607 | orig_search_start); |
| 1608 | search_start = orig_search_start; |
| 1609 | ret = find_search_start(root, &block_group, |
| 1610 | &search_start, total_needed, data); |
| 1611 | if (ret == -ENOSPC) |
| 1612 | goto enospc; |
| 1613 | if (ret) |
| 1614 | goto error; |
| 1615 | } |
| 1616 | |
| 1617 | search_start = stripe_align(root, search_start); |
| 1618 | ins->objectid = search_start; |
| 1619 | ins->offset = num_bytes; |
| 1620 | |
| 1621 | if (ins->objectid + num_bytes >= search_end) |
| 1622 | goto enospc; |
| 1623 | |
| 1624 | if (ins->objectid + num_bytes > |
| 1625 | block_group->key.objectid + block_group->key.offset) { |
| 1626 | search_start = block_group->key.objectid + |
| 1627 | block_group->key.offset; |
| 1628 | goto new_group; |
| 1629 | } |
| 1630 | |
| 1631 | if (test_range_bit(&info->extent_ins, ins->objectid, |
| 1632 | ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) { |
| 1633 | search_start = ins->objectid + num_bytes; |
| 1634 | goto new_group; |
| 1635 | } |
| 1636 | |
| 1637 | if (test_range_bit(&info->pinned_extents, ins->objectid, |
| 1638 | ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) { |
| 1639 | search_start = ins->objectid + num_bytes; |
| 1640 | goto new_group; |
| 1641 | } |
| 1642 | |
| 1643 | if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start && |
| 1644 | ins->objectid < exclude_start + exclude_nr)) { |
| 1645 | search_start = exclude_start + exclude_nr; |
| 1646 | goto new_group; |
| 1647 | } |
| 1648 | |
| 1649 | if (!(data & BTRFS_BLOCK_GROUP_DATA)) { |
| 1650 | block_group = btrfs_lookup_block_group(info, ins->objectid); |
| 1651 | if (block_group) |
| 1652 | trans->block_group = block_group; |
| 1653 | } |
| 1654 | ins->offset = num_bytes; |
| 1655 | if (last_ptr) { |
| 1656 | *last_ptr = ins->objectid + ins->offset; |
| 1657 | if (*last_ptr == |
| 1658 | btrfs_super_total_bytes(&root->fs_info->super_copy)) { |
| 1659 | *last_ptr = 0; |
| 1660 | } |
| 1661 | } |
| 1662 | return 0; |
| 1663 | |
| 1664 | new_group: |
| 1665 | if (search_start + num_bytes >= search_end) { |
| 1666 | enospc: |
| 1667 | search_start = orig_search_start; |
| 1668 | if (full_scan) { |
| 1669 | ret = -ENOSPC; |
| 1670 | goto error; |
| 1671 | } |
| 1672 | if (wrapped) { |
| 1673 | if (!full_scan) |
| 1674 | total_needed -= empty_size; |
| 1675 | full_scan = 1; |
| 1676 | } else |
| 1677 | wrapped = 1; |
| 1678 | } |
| 1679 | block_group = btrfs_lookup_block_group(info, search_start); |
| 1680 | cond_resched(); |
| 1681 | block_group = btrfs_find_block_group(root, block_group, |
| 1682 | search_start, data, 0); |
| 1683 | goto check_failed; |
| 1684 | |
| 1685 | error: |
| 1686 | return ret; |
| 1687 | } |
| 1688 | /* |
| 1689 | * finds a free extent and does all the dirty work required for allocation |
| 1690 | * returns the key for the extent through ins, and a tree buffer for |
| 1691 | * the first block of the extent through buf. |
| 1692 | * |
| 1693 | * returns 0 if everything worked, non-zero otherwise. |
| 1694 | */ |
| 1695 | int btrfs_alloc_extent(struct btrfs_trans_handle *trans, |
| 1696 | struct btrfs_root *root, |
| 1697 | u64 num_bytes, u64 root_objectid, u64 ref_generation, |
| 1698 | u64 owner, u64 owner_offset, |
| 1699 | u64 empty_size, u64 hint_byte, |
| 1700 | u64 search_end, struct btrfs_key *ins, int data) |
| 1701 | { |
| 1702 | int ret; |
| 1703 | int pending_ret; |
| 1704 | u64 super_used; |
| 1705 | u64 root_used; |
| 1706 | u64 search_start = 0; |
| 1707 | u64 new_hint; |
| 1708 | u64 alloc_profile; |
| 1709 | u32 sizes[2]; |
| 1710 | struct btrfs_fs_info *info = root->fs_info; |
| 1711 | struct btrfs_root *extent_root = info->extent_root; |
| 1712 | struct btrfs_extent_item *extent_item; |
| 1713 | struct btrfs_extent_ref *ref; |
| 1714 | struct btrfs_path *path; |
| 1715 | struct btrfs_key keys[2]; |
| 1716 | |
| 1717 | if (data) { |
| 1718 | alloc_profile = info->avail_data_alloc_bits & |
| 1719 | info->data_alloc_profile; |
| 1720 | data = BTRFS_BLOCK_GROUP_DATA | alloc_profile; |
| 1721 | } else if (root == root->fs_info->chunk_root) { |
| 1722 | alloc_profile = info->avail_system_alloc_bits & |
| 1723 | info->system_alloc_profile; |
| 1724 | data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile; |
| 1725 | } else { |
| 1726 | alloc_profile = info->avail_metadata_alloc_bits & |
| 1727 | info->metadata_alloc_profile; |
| 1728 | data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile; |
| 1729 | } |
| 1730 | |
| 1731 | if (root->ref_cows) { |
| 1732 | if (!(data & BTRFS_BLOCK_GROUP_METADATA)) { |
| 1733 | ret = do_chunk_alloc(trans, root->fs_info->extent_root, |
| 1734 | 2 * 1024 * 1024, |
| 1735 | BTRFS_BLOCK_GROUP_METADATA | |
| 1736 | (info->metadata_alloc_profile & |
| 1737 | info->avail_metadata_alloc_bits)); |
| 1738 | BUG_ON(ret); |
| 1739 | } |
| 1740 | ret = do_chunk_alloc(trans, root->fs_info->extent_root, |
| 1741 | num_bytes + 2 * 1024 * 1024, data); |
| 1742 | BUG_ON(ret); |
| 1743 | } |
| 1744 | |
| 1745 | new_hint = max(hint_byte, root->fs_info->alloc_start); |
| 1746 | if (new_hint < btrfs_super_total_bytes(&info->super_copy)) |
| 1747 | hint_byte = new_hint; |
| 1748 | |
| 1749 | WARN_ON(num_bytes < root->sectorsize); |
| 1750 | ret = find_free_extent(trans, root, num_bytes, empty_size, |
| 1751 | search_start, search_end, hint_byte, ins, |
| 1752 | trans->alloc_exclude_start, |
| 1753 | trans->alloc_exclude_nr, data); |
| 1754 | BUG_ON(ret); |
| 1755 | if (ret) |
| 1756 | return ret; |
| 1757 | |
| 1758 | /* block accounting for super block */ |
| 1759 | super_used = btrfs_super_bytes_used(&info->super_copy); |
| 1760 | btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes); |
| 1761 | |
| 1762 | /* block accounting for root item */ |
| 1763 | root_used = btrfs_root_used(&root->root_item); |
| 1764 | btrfs_set_root_used(&root->root_item, root_used + num_bytes); |
| 1765 | |
| 1766 | clear_extent_dirty(&root->fs_info->free_space_cache, |
| 1767 | ins->objectid, ins->objectid + ins->offset - 1, |
| 1768 | GFP_NOFS); |
| 1769 | |
| 1770 | if (root == extent_root) { |
| 1771 | set_extent_bits(&root->fs_info->extent_ins, ins->objectid, |
| 1772 | ins->objectid + ins->offset - 1, |
| 1773 | EXTENT_LOCKED, GFP_NOFS); |
| 1774 | goto update_block; |
| 1775 | } |
| 1776 | |
| 1777 | WARN_ON(trans->alloc_exclude_nr); |
| 1778 | trans->alloc_exclude_start = ins->objectid; |
| 1779 | trans->alloc_exclude_nr = ins->offset; |
| 1780 | |
| 1781 | memcpy(&keys[0], ins, sizeof(*ins)); |
| 1782 | keys[1].offset = hash_extent_ref(root_objectid, ref_generation, |
| 1783 | owner, owner_offset); |
| 1784 | keys[1].objectid = ins->objectid; |
| 1785 | keys[1].type = BTRFS_EXTENT_REF_KEY; |
| 1786 | sizes[0] = sizeof(*extent_item); |
| 1787 | sizes[1] = sizeof(*ref); |
| 1788 | |
| 1789 | path = btrfs_alloc_path(); |
| 1790 | BUG_ON(!path); |
| 1791 | |
| 1792 | ret = btrfs_insert_empty_items(trans, extent_root, path, keys, |
| 1793 | sizes, 2); |
| 1794 | |
| 1795 | BUG_ON(ret); |
| 1796 | extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 1797 | struct btrfs_extent_item); |
| 1798 | btrfs_set_extent_refs(path->nodes[0], extent_item, 1); |
| 1799 | ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, |
| 1800 | struct btrfs_extent_ref); |
| 1801 | |
| 1802 | btrfs_set_ref_root(path->nodes[0], ref, root_objectid); |
| 1803 | btrfs_set_ref_generation(path->nodes[0], ref, ref_generation); |
| 1804 | btrfs_set_ref_objectid(path->nodes[0], ref, owner); |
| 1805 | btrfs_set_ref_offset(path->nodes[0], ref, owner_offset); |
| 1806 | |
| 1807 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 1808 | |
| 1809 | trans->alloc_exclude_start = 0; |
| 1810 | trans->alloc_exclude_nr = 0; |
| 1811 | btrfs_free_path(path); |
| 1812 | finish_current_insert(trans, extent_root); |
| 1813 | pending_ret = del_pending_extents(trans, extent_root); |
| 1814 | |
| 1815 | if (ret) { |
| 1816 | return ret; |
| 1817 | } |
| 1818 | if (pending_ret) { |
| 1819 | return pending_ret; |
| 1820 | } |
| 1821 | |
| 1822 | update_block: |
| 1823 | ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0); |
| 1824 | if (ret) { |
| 1825 | printk("update block group failed for %Lu %Lu\n", |
| 1826 | ins->objectid, ins->offset); |
| 1827 | BUG(); |
| 1828 | } |
| 1829 | return 0; |
| 1830 | } |
| 1831 | |
| 1832 | /* |
| 1833 | * helper function to allocate a block for a given tree |
| 1834 | * returns the tree buffer or NULL. |
| 1835 | */ |
| 1836 | struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, |
| 1837 | struct btrfs_root *root, |
| 1838 | u32 blocksize, |
| 1839 | u64 root_objectid, u64 hint, |
| 1840 | u64 empty_size) |
| 1841 | { |
| 1842 | u64 ref_generation; |
| 1843 | |
| 1844 | if (root->ref_cows) |
| 1845 | ref_generation = trans->transid; |
| 1846 | else |
| 1847 | ref_generation = 0; |
| 1848 | |
| 1849 | |
| 1850 | return __btrfs_alloc_free_block(trans, root, blocksize, root_objectid, |
| 1851 | ref_generation, 0, 0, hint, empty_size); |
| 1852 | } |
| 1853 | |
| 1854 | /* |
| 1855 | * helper function to allocate a block for a given tree |
| 1856 | * returns the tree buffer or NULL. |
| 1857 | */ |
| 1858 | struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans, |
| 1859 | struct btrfs_root *root, |
| 1860 | u32 blocksize, |
| 1861 | u64 root_objectid, |
| 1862 | u64 ref_generation, |
| 1863 | u64 first_objectid, |
| 1864 | int level, |
| 1865 | u64 hint, |
| 1866 | u64 empty_size) |
| 1867 | { |
| 1868 | struct btrfs_key ins; |
| 1869 | int ret; |
| 1870 | struct extent_buffer *buf; |
| 1871 | |
| 1872 | ret = btrfs_alloc_extent(trans, root, blocksize, |
| 1873 | root_objectid, ref_generation, |
| 1874 | level, first_objectid, empty_size, hint, |
| 1875 | (u64)-1, &ins, 0); |
| 1876 | if (ret) { |
| 1877 | BUG_ON(ret > 0); |
| 1878 | return ERR_PTR(ret); |
| 1879 | } |
| 1880 | buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize); |
| 1881 | if (!buf) { |
| 1882 | btrfs_free_extent(trans, root, ins.objectid, blocksize, |
| 1883 | root->root_key.objectid, ref_generation, |
| 1884 | 0, 0, 0); |
| 1885 | return ERR_PTR(-ENOMEM); |
| 1886 | } |
| 1887 | btrfs_set_header_generation(buf, trans->transid); |
| 1888 | clean_tree_block(trans, root, buf); |
| 1889 | wait_on_tree_block_writeback(root, buf); |
| 1890 | btrfs_set_buffer_uptodate(buf); |
| 1891 | |
| 1892 | if (PageDirty(buf->first_page)) { |
| 1893 | printk("page %lu dirty\n", buf->first_page->index); |
| 1894 | WARN_ON(1); |
| 1895 | } |
| 1896 | |
| 1897 | set_extent_dirty(&trans->transaction->dirty_pages, buf->start, |
| 1898 | buf->start + buf->len - 1, GFP_NOFS); |
| 1899 | set_extent_bits(&BTRFS_I(root->fs_info->btree_inode)->io_tree, |
| 1900 | buf->start, buf->start + buf->len - 1, |
| 1901 | EXTENT_CSUM, GFP_NOFS); |
| 1902 | buf->flags |= EXTENT_CSUM; |
| 1903 | if (!btrfs_test_opt(root, SSD)) |
| 1904 | btrfs_set_buffer_defrag(buf); |
| 1905 | trans->blocks_used++; |
| 1906 | return buf; |
| 1907 | } |
| 1908 | |
| 1909 | static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans, |
| 1910 | struct btrfs_root *root, |
| 1911 | struct extent_buffer *leaf) |
| 1912 | { |
| 1913 | u64 leaf_owner; |
| 1914 | u64 leaf_generation; |
| 1915 | struct btrfs_key key; |
| 1916 | struct btrfs_file_extent_item *fi; |
| 1917 | int i; |
| 1918 | int nritems; |
| 1919 | int ret; |
| 1920 | |
| 1921 | BUG_ON(!btrfs_is_leaf(leaf)); |
| 1922 | nritems = btrfs_header_nritems(leaf); |
| 1923 | leaf_owner = btrfs_header_owner(leaf); |
| 1924 | leaf_generation = btrfs_header_generation(leaf); |
| 1925 | |
| 1926 | for (i = 0; i < nritems; i++) { |
| 1927 | u64 disk_bytenr; |
| 1928 | |
| 1929 | btrfs_item_key_to_cpu(leaf, &key, i); |
| 1930 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) |
| 1931 | continue; |
| 1932 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); |
| 1933 | if (btrfs_file_extent_type(leaf, fi) == |
| 1934 | BTRFS_FILE_EXTENT_INLINE) |
| 1935 | continue; |
| 1936 | /* |
| 1937 | * FIXME make sure to insert a trans record that |
| 1938 | * repeats the snapshot del on crash |
| 1939 | */ |
| 1940 | disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); |
| 1941 | if (disk_bytenr == 0) |
| 1942 | continue; |
| 1943 | ret = btrfs_free_extent(trans, root, disk_bytenr, |
| 1944 | btrfs_file_extent_disk_num_bytes(leaf, fi), |
| 1945 | leaf_owner, leaf_generation, |
| 1946 | key.objectid, key.offset, 0); |
| 1947 | BUG_ON(ret); |
| 1948 | } |
| 1949 | return 0; |
| 1950 | } |
| 1951 | |
| 1952 | static void noinline reada_walk_down(struct btrfs_root *root, |
| 1953 | struct extent_buffer *node, |
| 1954 | int slot) |
| 1955 | { |
| 1956 | u64 bytenr; |
| 1957 | u64 last = 0; |
| 1958 | u32 nritems; |
| 1959 | u32 refs; |
| 1960 | u32 blocksize; |
| 1961 | int ret; |
| 1962 | int i; |
| 1963 | int level; |
| 1964 | int skipped = 0; |
| 1965 | |
| 1966 | nritems = btrfs_header_nritems(node); |
| 1967 | level = btrfs_header_level(node); |
| 1968 | if (level) |
| 1969 | return; |
| 1970 | |
| 1971 | for (i = slot; i < nritems && skipped < 32; i++) { |
| 1972 | bytenr = btrfs_node_blockptr(node, i); |
| 1973 | if (last && ((bytenr > last && bytenr - last > 32 * 1024) || |
| 1974 | (last > bytenr && last - bytenr > 32 * 1024))) { |
| 1975 | skipped++; |
| 1976 | continue; |
| 1977 | } |
| 1978 | blocksize = btrfs_level_size(root, level - 1); |
| 1979 | if (i != slot) { |
| 1980 | ret = lookup_extent_ref(NULL, root, bytenr, |
| 1981 | blocksize, &refs); |
| 1982 | BUG_ON(ret); |
| 1983 | if (refs != 1) { |
| 1984 | skipped++; |
| 1985 | continue; |
| 1986 | } |
| 1987 | } |
| 1988 | mutex_unlock(&root->fs_info->fs_mutex); |
| 1989 | ret = readahead_tree_block(root, bytenr, blocksize); |
| 1990 | last = bytenr + blocksize; |
| 1991 | cond_resched(); |
| 1992 | mutex_lock(&root->fs_info->fs_mutex); |
| 1993 | if (ret) |
| 1994 | break; |
| 1995 | } |
| 1996 | } |
| 1997 | |
| 1998 | /* |
| 1999 | * helper function for drop_snapshot, this walks down the tree dropping ref |
| 2000 | * counts as it goes. |
| 2001 | */ |
| 2002 | static int noinline walk_down_tree(struct btrfs_trans_handle *trans, |
| 2003 | struct btrfs_root *root, |
| 2004 | struct btrfs_path *path, int *level) |
| 2005 | { |
| 2006 | u64 root_owner; |
| 2007 | u64 root_gen; |
| 2008 | u64 bytenr; |
| 2009 | struct extent_buffer *next; |
| 2010 | struct extent_buffer *cur; |
| 2011 | struct extent_buffer *parent; |
| 2012 | u32 blocksize; |
| 2013 | int ret; |
| 2014 | u32 refs; |
| 2015 | |
| 2016 | WARN_ON(*level < 0); |
| 2017 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 2018 | ret = lookup_extent_ref(trans, root, |
| 2019 | path->nodes[*level]->start, |
| 2020 | path->nodes[*level]->len, &refs); |
| 2021 | BUG_ON(ret); |
| 2022 | if (refs > 1) |
| 2023 | goto out; |
| 2024 | |
| 2025 | /* |
| 2026 | * walk down to the last node level and free all the leaves |
| 2027 | */ |
| 2028 | while(*level >= 0) { |
| 2029 | WARN_ON(*level < 0); |
| 2030 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 2031 | cur = path->nodes[*level]; |
| 2032 | |
| 2033 | if (btrfs_header_level(cur) != *level) |
| 2034 | WARN_ON(1); |
| 2035 | |
| 2036 | if (path->slots[*level] >= |
| 2037 | btrfs_header_nritems(cur)) |
| 2038 | break; |
| 2039 | if (*level == 0) { |
| 2040 | ret = drop_leaf_ref(trans, root, cur); |
| 2041 | BUG_ON(ret); |
| 2042 | break; |
| 2043 | } |
| 2044 | bytenr = btrfs_node_blockptr(cur, path->slots[*level]); |
| 2045 | blocksize = btrfs_level_size(root, *level - 1); |
| 2046 | ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs); |
| 2047 | BUG_ON(ret); |
| 2048 | if (refs != 1) { |
| 2049 | parent = path->nodes[*level]; |
| 2050 | root_owner = btrfs_header_owner(parent); |
| 2051 | root_gen = btrfs_header_generation(parent); |
| 2052 | path->slots[*level]++; |
| 2053 | ret = btrfs_free_extent(trans, root, bytenr, |
| 2054 | blocksize, root_owner, |
| 2055 | root_gen, 0, 0, 1); |
| 2056 | BUG_ON(ret); |
| 2057 | continue; |
| 2058 | } |
| 2059 | next = btrfs_find_tree_block(root, bytenr, blocksize); |
| 2060 | if (!next || !btrfs_buffer_uptodate(next)) { |
| 2061 | free_extent_buffer(next); |
| 2062 | reada_walk_down(root, cur, path->slots[*level]); |
| 2063 | |
| 2064 | mutex_unlock(&root->fs_info->fs_mutex); |
| 2065 | next = read_tree_block(root, bytenr, blocksize); |
| 2066 | mutex_lock(&root->fs_info->fs_mutex); |
| 2067 | |
| 2068 | /* we've dropped the lock, double check */ |
| 2069 | ret = lookup_extent_ref(trans, root, bytenr, |
| 2070 | blocksize, &refs); |
| 2071 | BUG_ON(ret); |
| 2072 | if (refs != 1) { |
| 2073 | parent = path->nodes[*level]; |
| 2074 | root_owner = btrfs_header_owner(parent); |
| 2075 | root_gen = btrfs_header_generation(parent); |
| 2076 | |
| 2077 | path->slots[*level]++; |
| 2078 | free_extent_buffer(next); |
| 2079 | ret = btrfs_free_extent(trans, root, bytenr, |
| 2080 | blocksize, |
| 2081 | root_owner, |
| 2082 | root_gen, 0, 0, 1); |
| 2083 | BUG_ON(ret); |
| 2084 | continue; |
| 2085 | } |
| 2086 | } else if (next) { |
| 2087 | btrfs_verify_block_csum(root, next); |
| 2088 | } |
| 2089 | WARN_ON(*level <= 0); |
| 2090 | if (path->nodes[*level-1]) |
| 2091 | free_extent_buffer(path->nodes[*level-1]); |
| 2092 | path->nodes[*level-1] = next; |
| 2093 | *level = btrfs_header_level(next); |
| 2094 | path->slots[*level] = 0; |
| 2095 | } |
| 2096 | out: |
| 2097 | WARN_ON(*level < 0); |
| 2098 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 2099 | |
| 2100 | if (path->nodes[*level] == root->node) { |
| 2101 | root_owner = root->root_key.objectid; |
| 2102 | parent = path->nodes[*level]; |
| 2103 | } else { |
| 2104 | parent = path->nodes[*level + 1]; |
| 2105 | root_owner = btrfs_header_owner(parent); |
| 2106 | } |
| 2107 | |
| 2108 | root_gen = btrfs_header_generation(parent); |
| 2109 | ret = btrfs_free_extent(trans, root, path->nodes[*level]->start, |
| 2110 | path->nodes[*level]->len, |
| 2111 | root_owner, root_gen, 0, 0, 1); |
| 2112 | free_extent_buffer(path->nodes[*level]); |
| 2113 | path->nodes[*level] = NULL; |
| 2114 | *level += 1; |
| 2115 | BUG_ON(ret); |
| 2116 | return 0; |
| 2117 | } |
| 2118 | |
| 2119 | /* |
| 2120 | * helper for dropping snapshots. This walks back up the tree in the path |
| 2121 | * to find the first node higher up where we haven't yet gone through |
| 2122 | * all the slots |
| 2123 | */ |
| 2124 | static int noinline walk_up_tree(struct btrfs_trans_handle *trans, |
| 2125 | struct btrfs_root *root, |
| 2126 | struct btrfs_path *path, int *level) |
| 2127 | { |
| 2128 | u64 root_owner; |
| 2129 | u64 root_gen; |
| 2130 | struct btrfs_root_item *root_item = &root->root_item; |
| 2131 | int i; |
| 2132 | int slot; |
| 2133 | int ret; |
| 2134 | |
| 2135 | for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { |
| 2136 | slot = path->slots[i]; |
| 2137 | if (slot < btrfs_header_nritems(path->nodes[i]) - 1) { |
| 2138 | struct extent_buffer *node; |
| 2139 | struct btrfs_disk_key disk_key; |
| 2140 | node = path->nodes[i]; |
| 2141 | path->slots[i]++; |
| 2142 | *level = i; |
| 2143 | WARN_ON(*level == 0); |
| 2144 | btrfs_node_key(node, &disk_key, path->slots[i]); |
| 2145 | memcpy(&root_item->drop_progress, |
| 2146 | &disk_key, sizeof(disk_key)); |
| 2147 | root_item->drop_level = i; |
| 2148 | return 0; |
| 2149 | } else { |
| 2150 | if (path->nodes[*level] == root->node) { |
| 2151 | root_owner = root->root_key.objectid; |
| 2152 | root_gen = |
| 2153 | btrfs_header_generation(path->nodes[*level]); |
| 2154 | } else { |
| 2155 | struct extent_buffer *node; |
| 2156 | node = path->nodes[*level + 1]; |
| 2157 | root_owner = btrfs_header_owner(node); |
| 2158 | root_gen = btrfs_header_generation(node); |
| 2159 | } |
| 2160 | ret = btrfs_free_extent(trans, root, |
| 2161 | path->nodes[*level]->start, |
| 2162 | path->nodes[*level]->len, |
| 2163 | root_owner, root_gen, 0, 0, 1); |
| 2164 | BUG_ON(ret); |
| 2165 | free_extent_buffer(path->nodes[*level]); |
| 2166 | path->nodes[*level] = NULL; |
| 2167 | *level = i + 1; |
| 2168 | } |
| 2169 | } |
| 2170 | return 1; |
| 2171 | } |
| 2172 | |
| 2173 | /* |
| 2174 | * drop the reference count on the tree rooted at 'snap'. This traverses |
| 2175 | * the tree freeing any blocks that have a ref count of zero after being |
| 2176 | * decremented. |
| 2177 | */ |
| 2178 | int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root |
| 2179 | *root) |
| 2180 | { |
| 2181 | int ret = 0; |
| 2182 | int wret; |
| 2183 | int level; |
| 2184 | struct btrfs_path *path; |
| 2185 | int i; |
| 2186 | int orig_level; |
| 2187 | struct btrfs_root_item *root_item = &root->root_item; |
| 2188 | |
| 2189 | path = btrfs_alloc_path(); |
| 2190 | BUG_ON(!path); |
| 2191 | |
| 2192 | level = btrfs_header_level(root->node); |
| 2193 | orig_level = level; |
| 2194 | if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { |
| 2195 | path->nodes[level] = root->node; |
| 2196 | extent_buffer_get(root->node); |
| 2197 | path->slots[level] = 0; |
| 2198 | } else { |
| 2199 | struct btrfs_key key; |
| 2200 | struct btrfs_disk_key found_key; |
| 2201 | struct extent_buffer *node; |
| 2202 | |
| 2203 | btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); |
| 2204 | level = root_item->drop_level; |
| 2205 | path->lowest_level = level; |
| 2206 | wret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 2207 | if (wret < 0) { |
| 2208 | ret = wret; |
| 2209 | goto out; |
| 2210 | } |
| 2211 | node = path->nodes[level]; |
| 2212 | btrfs_node_key(node, &found_key, path->slots[level]); |
| 2213 | WARN_ON(memcmp(&found_key, &root_item->drop_progress, |
| 2214 | sizeof(found_key))); |
| 2215 | } |
| 2216 | while(1) { |
| 2217 | wret = walk_down_tree(trans, root, path, &level); |
| 2218 | if (wret > 0) |
| 2219 | break; |
| 2220 | if (wret < 0) |
| 2221 | ret = wret; |
| 2222 | |
| 2223 | wret = walk_up_tree(trans, root, path, &level); |
| 2224 | if (wret > 0) |
| 2225 | break; |
| 2226 | if (wret < 0) |
| 2227 | ret = wret; |
| 2228 | ret = -EAGAIN; |
| 2229 | break; |
| 2230 | } |
| 2231 | for (i = 0; i <= orig_level; i++) { |
| 2232 | if (path->nodes[i]) { |
| 2233 | free_extent_buffer(path->nodes[i]); |
| 2234 | path->nodes[i] = NULL; |
| 2235 | } |
| 2236 | } |
| 2237 | out: |
| 2238 | btrfs_free_path(path); |
| 2239 | return ret; |
| 2240 | } |
| 2241 | |
| 2242 | int btrfs_free_block_groups(struct btrfs_fs_info *info) |
| 2243 | { |
| 2244 | u64 start; |
| 2245 | u64 end; |
| 2246 | u64 ptr; |
| 2247 | int ret; |
| 2248 | while(1) { |
| 2249 | ret = find_first_extent_bit(&info->block_group_cache, 0, |
| 2250 | &start, &end, (unsigned int)-1); |
| 2251 | if (ret) |
| 2252 | break; |
| 2253 | ret = get_state_private(&info->block_group_cache, start, &ptr); |
| 2254 | if (!ret) |
| 2255 | kfree((void *)(unsigned long)ptr); |
| 2256 | clear_extent_bits(&info->block_group_cache, start, |
| 2257 | end, (unsigned int)-1, GFP_NOFS); |
| 2258 | } |
| 2259 | while(1) { |
| 2260 | ret = find_first_extent_bit(&info->free_space_cache, 0, |
| 2261 | &start, &end, EXTENT_DIRTY); |
| 2262 | if (ret) |
| 2263 | break; |
| 2264 | clear_extent_dirty(&info->free_space_cache, start, |
| 2265 | end, GFP_NOFS); |
| 2266 | } |
| 2267 | return 0; |
| 2268 | } |
| 2269 | |
| 2270 | static int noinline relocate_inode_pages(struct inode *inode, u64 start, |
| 2271 | u64 len) |
| 2272 | { |
| 2273 | u64 page_start; |
| 2274 | u64 page_end; |
| 2275 | u64 delalloc_start; |
| 2276 | u64 existing_delalloc; |
| 2277 | unsigned long last_index; |
| 2278 | unsigned long i; |
| 2279 | struct page *page; |
| 2280 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| 2281 | struct file_ra_state *ra; |
| 2282 | |
| 2283 | ra = kzalloc(sizeof(*ra), GFP_NOFS); |
| 2284 | |
| 2285 | mutex_lock(&inode->i_mutex); |
| 2286 | i = start >> PAGE_CACHE_SHIFT; |
| 2287 | last_index = (start + len - 1) >> PAGE_CACHE_SHIFT; |
| 2288 | |
| 2289 | file_ra_state_init(ra, inode->i_mapping); |
| 2290 | btrfs_force_ra(inode->i_mapping, ra, NULL, i, last_index); |
| 2291 | kfree(ra); |
| 2292 | |
| 2293 | for (; i <= last_index; i++) { |
| 2294 | page = grab_cache_page(inode->i_mapping, i); |
| 2295 | if (!page) |
| 2296 | goto out_unlock; |
| 2297 | if (!PageUptodate(page)) { |
| 2298 | btrfs_readpage(NULL, page); |
| 2299 | lock_page(page); |
| 2300 | if (!PageUptodate(page)) { |
| 2301 | unlock_page(page); |
| 2302 | page_cache_release(page); |
| 2303 | goto out_unlock; |
| 2304 | } |
| 2305 | } |
| 2306 | page_start = (u64)page->index << PAGE_CACHE_SHIFT; |
| 2307 | page_end = page_start + PAGE_CACHE_SIZE - 1; |
| 2308 | |
| 2309 | lock_extent(io_tree, page_start, page_end, GFP_NOFS); |
| 2310 | |
| 2311 | delalloc_start = page_start; |
| 2312 | existing_delalloc = count_range_bits(io_tree, |
| 2313 | &delalloc_start, page_end, |
| 2314 | PAGE_CACHE_SIZE, EXTENT_DELALLOC); |
| 2315 | |
| 2316 | set_extent_delalloc(io_tree, page_start, |
| 2317 | page_end, GFP_NOFS); |
| 2318 | |
| 2319 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); |
| 2320 | set_page_dirty(page); |
| 2321 | unlock_page(page); |
| 2322 | page_cache_release(page); |
| 2323 | } |
| 2324 | |
| 2325 | out_unlock: |
| 2326 | mutex_unlock(&inode->i_mutex); |
| 2327 | return 0; |
| 2328 | } |
| 2329 | |
| 2330 | /* |
| 2331 | * note, this releases the path |
| 2332 | */ |
| 2333 | static int noinline relocate_one_reference(struct btrfs_root *extent_root, |
| 2334 | struct btrfs_path *path, |
| 2335 | struct btrfs_key *extent_key) |
| 2336 | { |
| 2337 | struct inode *inode; |
| 2338 | struct btrfs_root *found_root; |
| 2339 | struct btrfs_key *root_location; |
| 2340 | struct btrfs_extent_ref *ref; |
| 2341 | u64 ref_root; |
| 2342 | u64 ref_gen; |
| 2343 | u64 ref_objectid; |
| 2344 | u64 ref_offset; |
| 2345 | int ret; |
| 2346 | |
| 2347 | ref = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 2348 | struct btrfs_extent_ref); |
| 2349 | ref_root = btrfs_ref_root(path->nodes[0], ref); |
| 2350 | ref_gen = btrfs_ref_generation(path->nodes[0], ref); |
| 2351 | ref_objectid = btrfs_ref_objectid(path->nodes[0], ref); |
| 2352 | ref_offset = btrfs_ref_offset(path->nodes[0], ref); |
| 2353 | btrfs_release_path(extent_root, path); |
| 2354 | |
| 2355 | root_location = kmalloc(sizeof(*root_location), GFP_NOFS); |
| 2356 | root_location->objectid = ref_root; |
| 2357 | if (ref_gen == 0) |
| 2358 | root_location->offset = 0; |
| 2359 | else |
| 2360 | root_location->offset = (u64)-1; |
| 2361 | root_location->type = BTRFS_ROOT_ITEM_KEY; |
| 2362 | |
| 2363 | found_root = btrfs_read_fs_root_no_name(extent_root->fs_info, |
| 2364 | root_location); |
| 2365 | BUG_ON(!found_root); |
| 2366 | kfree(root_location); |
| 2367 | |
| 2368 | if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) { |
| 2369 | mutex_unlock(&extent_root->fs_info->fs_mutex); |
| 2370 | inode = btrfs_iget_locked(extent_root->fs_info->sb, |
| 2371 | ref_objectid, found_root); |
| 2372 | if (inode->i_state & I_NEW) { |
| 2373 | /* the inode and parent dir are two different roots */ |
| 2374 | BTRFS_I(inode)->root = found_root; |
| 2375 | BTRFS_I(inode)->location.objectid = ref_objectid; |
| 2376 | BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY; |
| 2377 | BTRFS_I(inode)->location.offset = 0; |
| 2378 | btrfs_read_locked_inode(inode); |
| 2379 | unlock_new_inode(inode); |
| 2380 | |
| 2381 | } |
| 2382 | /* this can happen if the reference is not against |
| 2383 | * the latest version of the tree root |
| 2384 | */ |
| 2385 | if (is_bad_inode(inode)) { |
| 2386 | mutex_lock(&extent_root->fs_info->fs_mutex); |
| 2387 | goto out; |
| 2388 | } |
| 2389 | relocate_inode_pages(inode, ref_offset, extent_key->offset); |
| 2390 | /* FIXME, data=ordered will help get rid of this */ |
| 2391 | filemap_fdatawrite(inode->i_mapping); |
| 2392 | iput(inode); |
| 2393 | mutex_lock(&extent_root->fs_info->fs_mutex); |
| 2394 | } else { |
| 2395 | struct btrfs_trans_handle *trans; |
| 2396 | struct btrfs_key found_key; |
| 2397 | struct extent_buffer *eb; |
| 2398 | int level; |
| 2399 | int i; |
| 2400 | |
| 2401 | trans = btrfs_start_transaction(found_root, 1); |
| 2402 | eb = read_tree_block(found_root, extent_key->objectid, |
| 2403 | extent_key->offset); |
| 2404 | level = btrfs_header_level(eb); |
| 2405 | |
| 2406 | if (level == 0) |
| 2407 | btrfs_item_key_to_cpu(eb, &found_key, 0); |
| 2408 | else |
| 2409 | btrfs_node_key_to_cpu(eb, &found_key, 0); |
| 2410 | |
| 2411 | free_extent_buffer(eb); |
| 2412 | |
| 2413 | path->lowest_level = level; |
| 2414 | path->reada = 2; |
| 2415 | ret = btrfs_search_slot(trans, found_root, &found_key, path, |
| 2416 | 0, 1); |
| 2417 | path->lowest_level = 0; |
| 2418 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
| 2419 | if (!path->nodes[i]) |
| 2420 | break; |
| 2421 | free_extent_buffer(path->nodes[i]); |
| 2422 | path->nodes[i] = NULL; |
| 2423 | } |
| 2424 | btrfs_release_path(found_root, path); |
| 2425 | btrfs_end_transaction(trans, found_root); |
| 2426 | } |
| 2427 | |
| 2428 | out: |
| 2429 | return 0; |
| 2430 | } |
| 2431 | |
| 2432 | static int noinline relocate_one_extent(struct btrfs_root *extent_root, |
| 2433 | struct btrfs_path *path, |
| 2434 | struct btrfs_key *extent_key) |
| 2435 | { |
| 2436 | struct btrfs_key key; |
| 2437 | struct btrfs_key found_key; |
| 2438 | struct extent_buffer *leaf; |
| 2439 | u32 nritems; |
| 2440 | u32 item_size; |
| 2441 | int ret = 0; |
| 2442 | |
| 2443 | key.objectid = extent_key->objectid; |
| 2444 | key.type = BTRFS_EXTENT_REF_KEY; |
| 2445 | key.offset = 0; |
| 2446 | |
| 2447 | while(1) { |
| 2448 | ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); |
| 2449 | |
| 2450 | if (ret < 0) |
| 2451 | goto out; |
| 2452 | |
| 2453 | ret = 0; |
| 2454 | leaf = path->nodes[0]; |
| 2455 | nritems = btrfs_header_nritems(leaf); |
| 2456 | if (path->slots[0] == nritems) |
| 2457 | goto out; |
| 2458 | |
| 2459 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2460 | if (found_key.objectid != extent_key->objectid) |
| 2461 | break; |
| 2462 | |
| 2463 | if (found_key.type != BTRFS_EXTENT_REF_KEY) |
| 2464 | break; |
| 2465 | |
| 2466 | key.offset = found_key.offset + 1; |
| 2467 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
| 2468 | |
| 2469 | ret = relocate_one_reference(extent_root, path, extent_key); |
| 2470 | if (ret) |
| 2471 | goto out; |
| 2472 | } |
| 2473 | ret = 0; |
| 2474 | out: |
| 2475 | btrfs_release_path(extent_root, path); |
| 2476 | return ret; |
| 2477 | } |
| 2478 | |
| 2479 | int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size) |
| 2480 | { |
| 2481 | struct btrfs_trans_handle *trans; |
| 2482 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
| 2483 | struct btrfs_path *path; |
| 2484 | u64 cur_byte; |
| 2485 | u64 total_found; |
| 2486 | struct btrfs_fs_info *info = root->fs_info; |
| 2487 | struct extent_io_tree *block_group_cache; |
| 2488 | struct btrfs_key key; |
| 2489 | struct btrfs_key found_key; |
| 2490 | struct extent_buffer *leaf; |
| 2491 | u32 nritems; |
| 2492 | int ret; |
| 2493 | int progress = 0; |
| 2494 | |
| 2495 | btrfs_set_super_total_bytes(&info->super_copy, new_size); |
| 2496 | clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1, |
| 2497 | GFP_NOFS); |
| 2498 | block_group_cache = &info->block_group_cache; |
| 2499 | path = btrfs_alloc_path(); |
| 2500 | root = root->fs_info->extent_root; |
| 2501 | path->reada = 2; |
| 2502 | |
| 2503 | again: |
| 2504 | total_found = 0; |
| 2505 | key.objectid = new_size; |
| 2506 | key.offset = 0; |
| 2507 | key.type = 0; |
| 2508 | cur_byte = key.objectid; |
| 2509 | |
| 2510 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 2511 | if (ret < 0) |
| 2512 | goto out; |
| 2513 | |
| 2514 | ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY); |
| 2515 | if (ret < 0) |
| 2516 | goto out; |
| 2517 | if (ret == 0) { |
| 2518 | leaf = path->nodes[0]; |
| 2519 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2520 | if (found_key.objectid + found_key.offset > new_size) { |
| 2521 | cur_byte = found_key.objectid; |
| 2522 | key.objectid = cur_byte; |
| 2523 | } |
| 2524 | } |
| 2525 | btrfs_release_path(root, path); |
| 2526 | |
| 2527 | while(1) { |
| 2528 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 2529 | if (ret < 0) |
| 2530 | goto out; |
| 2531 | |
| 2532 | leaf = path->nodes[0]; |
| 2533 | nritems = btrfs_header_nritems(leaf); |
| 2534 | next: |
| 2535 | if (path->slots[0] >= nritems) { |
| 2536 | ret = btrfs_next_leaf(root, path); |
| 2537 | if (ret < 0) |
| 2538 | goto out; |
| 2539 | if (ret == 1) { |
| 2540 | ret = 0; |
| 2541 | break; |
| 2542 | } |
| 2543 | leaf = path->nodes[0]; |
| 2544 | nritems = btrfs_header_nritems(leaf); |
| 2545 | } |
| 2546 | |
| 2547 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2548 | |
| 2549 | if (progress && need_resched()) { |
| 2550 | memcpy(&key, &found_key, sizeof(key)); |
| 2551 | mutex_unlock(&root->fs_info->fs_mutex); |
| 2552 | cond_resched(); |
| 2553 | mutex_lock(&root->fs_info->fs_mutex); |
| 2554 | btrfs_release_path(root, path); |
| 2555 | btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 2556 | progress = 0; |
| 2557 | goto next; |
| 2558 | } |
| 2559 | progress = 1; |
| 2560 | |
| 2561 | if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY || |
| 2562 | found_key.objectid + found_key.offset <= cur_byte) { |
| 2563 | path->slots[0]++; |
| 2564 | goto next; |
| 2565 | } |
| 2566 | |
| 2567 | total_found++; |
| 2568 | cur_byte = found_key.objectid + found_key.offset; |
| 2569 | key.objectid = cur_byte; |
| 2570 | btrfs_release_path(root, path); |
| 2571 | ret = relocate_one_extent(root, path, &found_key); |
| 2572 | } |
| 2573 | |
| 2574 | btrfs_release_path(root, path); |
| 2575 | |
| 2576 | if (total_found > 0) { |
| 2577 | trans = btrfs_start_transaction(tree_root, 1); |
| 2578 | btrfs_commit_transaction(trans, tree_root); |
| 2579 | |
| 2580 | mutex_unlock(&root->fs_info->fs_mutex); |
| 2581 | btrfs_clean_old_snapshots(tree_root); |
| 2582 | mutex_lock(&root->fs_info->fs_mutex); |
| 2583 | |
| 2584 | trans = btrfs_start_transaction(tree_root, 1); |
| 2585 | btrfs_commit_transaction(trans, tree_root); |
| 2586 | goto again; |
| 2587 | } |
| 2588 | |
| 2589 | trans = btrfs_start_transaction(root, 1); |
| 2590 | key.objectid = new_size; |
| 2591 | key.offset = 0; |
| 2592 | key.type = 0; |
| 2593 | while(1) { |
| 2594 | u64 ptr; |
| 2595 | |
| 2596 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| 2597 | if (ret < 0) |
| 2598 | goto out; |
| 2599 | |
| 2600 | leaf = path->nodes[0]; |
| 2601 | nritems = btrfs_header_nritems(leaf); |
| 2602 | bg_next: |
| 2603 | if (path->slots[0] >= nritems) { |
| 2604 | ret = btrfs_next_leaf(root, path); |
| 2605 | if (ret < 0) |
| 2606 | break; |
| 2607 | if (ret == 1) { |
| 2608 | ret = 0; |
| 2609 | break; |
| 2610 | } |
| 2611 | leaf = path->nodes[0]; |
| 2612 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2613 | |
| 2614 | /* |
| 2615 | * btrfs_next_leaf doesn't cow buffers, we have to |
| 2616 | * do the search again |
| 2617 | */ |
| 2618 | memcpy(&key, &found_key, sizeof(key)); |
| 2619 | btrfs_release_path(root, path); |
| 2620 | goto resched_check; |
| 2621 | } |
| 2622 | |
| 2623 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2624 | if (btrfs_key_type(&found_key) != BTRFS_BLOCK_GROUP_ITEM_KEY) { |
| 2625 | printk("shrinker found key %Lu %u %Lu\n", |
| 2626 | found_key.objectid, found_key.type, |
| 2627 | found_key.offset); |
| 2628 | path->slots[0]++; |
| 2629 | goto bg_next; |
| 2630 | } |
| 2631 | ret = get_state_private(&info->block_group_cache, |
| 2632 | found_key.objectid, &ptr); |
| 2633 | if (!ret) |
| 2634 | kfree((void *)(unsigned long)ptr); |
| 2635 | |
| 2636 | clear_extent_bits(&info->block_group_cache, found_key.objectid, |
| 2637 | found_key.objectid + found_key.offset - 1, |
| 2638 | (unsigned int)-1, GFP_NOFS); |
| 2639 | |
| 2640 | key.objectid = found_key.objectid + 1; |
| 2641 | btrfs_del_item(trans, root, path); |
| 2642 | btrfs_release_path(root, path); |
| 2643 | resched_check: |
| 2644 | if (need_resched()) { |
| 2645 | mutex_unlock(&root->fs_info->fs_mutex); |
| 2646 | cond_resched(); |
| 2647 | mutex_lock(&root->fs_info->fs_mutex); |
| 2648 | } |
| 2649 | } |
| 2650 | clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1, |
| 2651 | GFP_NOFS); |
| 2652 | btrfs_commit_transaction(trans, root); |
| 2653 | out: |
| 2654 | btrfs_free_path(path); |
| 2655 | return ret; |
| 2656 | } |
| 2657 | |
| 2658 | int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans, |
| 2659 | struct btrfs_root *root, u64 new_size) |
| 2660 | { |
| 2661 | btrfs_set_super_total_bytes(&root->fs_info->super_copy, new_size); |
| 2662 | return 0; |
| 2663 | } |
| 2664 | |
| 2665 | int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path, |
| 2666 | struct btrfs_key *key) |
| 2667 | { |
| 2668 | int ret; |
| 2669 | struct btrfs_key found_key; |
| 2670 | struct extent_buffer *leaf; |
| 2671 | int slot; |
| 2672 | |
| 2673 | ret = btrfs_search_slot(NULL, root, key, path, 0, 0); |
| 2674 | if (ret < 0) |
| 2675 | return ret; |
| 2676 | while(1) { |
| 2677 | slot = path->slots[0]; |
| 2678 | leaf = path->nodes[0]; |
| 2679 | if (slot >= btrfs_header_nritems(leaf)) { |
| 2680 | ret = btrfs_next_leaf(root, path); |
| 2681 | if (ret == 0) |
| 2682 | continue; |
| 2683 | if (ret < 0) |
| 2684 | goto error; |
| 2685 | break; |
| 2686 | } |
| 2687 | btrfs_item_key_to_cpu(leaf, &found_key, slot); |
| 2688 | |
| 2689 | if (found_key.objectid >= key->objectid && |
| 2690 | found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) |
| 2691 | return 0; |
| 2692 | path->slots[0]++; |
| 2693 | } |
| 2694 | ret = -ENOENT; |
| 2695 | error: |
| 2696 | return ret; |
| 2697 | } |
| 2698 | |
| 2699 | int btrfs_read_block_groups(struct btrfs_root *root) |
| 2700 | { |
| 2701 | struct btrfs_path *path; |
| 2702 | int ret; |
| 2703 | int bit; |
| 2704 | struct btrfs_block_group_cache *cache; |
| 2705 | struct btrfs_fs_info *info = root->fs_info; |
| 2706 | struct btrfs_space_info *space_info; |
| 2707 | struct extent_io_tree *block_group_cache; |
| 2708 | struct btrfs_key key; |
| 2709 | struct btrfs_key found_key; |
| 2710 | struct extent_buffer *leaf; |
| 2711 | |
| 2712 | block_group_cache = &info->block_group_cache; |
| 2713 | root = info->extent_root; |
| 2714 | key.objectid = 0; |
| 2715 | key.offset = 0; |
| 2716 | btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY); |
| 2717 | path = btrfs_alloc_path(); |
| 2718 | if (!path) |
| 2719 | return -ENOMEM; |
| 2720 | |
| 2721 | while(1) { |
| 2722 | ret = find_first_block_group(root, path, &key); |
| 2723 | if (ret > 0) { |
| 2724 | ret = 0; |
| 2725 | goto error; |
| 2726 | } |
| 2727 | if (ret != 0) |
| 2728 | goto error; |
| 2729 | |
| 2730 | leaf = path->nodes[0]; |
| 2731 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 2732 | cache = kmalloc(sizeof(*cache), GFP_NOFS); |
| 2733 | if (!cache) { |
| 2734 | ret = -ENOMEM; |
| 2735 | break; |
| 2736 | } |
| 2737 | |
| 2738 | read_extent_buffer(leaf, &cache->item, |
| 2739 | btrfs_item_ptr_offset(leaf, path->slots[0]), |
| 2740 | sizeof(cache->item)); |
| 2741 | memcpy(&cache->key, &found_key, sizeof(found_key)); |
| 2742 | cache->cached = 0; |
| 2743 | cache->pinned = 0; |
| 2744 | |
| 2745 | key.objectid = found_key.objectid + found_key.offset; |
| 2746 | btrfs_release_path(root, path); |
| 2747 | cache->flags = btrfs_block_group_flags(&cache->item); |
| 2748 | bit = 0; |
| 2749 | if (cache->flags & BTRFS_BLOCK_GROUP_DATA) { |
| 2750 | bit = BLOCK_GROUP_DATA; |
| 2751 | } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 2752 | bit = BLOCK_GROUP_SYSTEM; |
| 2753 | } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) { |
| 2754 | bit = BLOCK_GROUP_METADATA; |
| 2755 | } |
| 2756 | set_avail_alloc_bits(info, cache->flags); |
| 2757 | |
| 2758 | ret = update_space_info(info, cache->flags, found_key.offset, |
| 2759 | btrfs_block_group_used(&cache->item), |
| 2760 | &space_info); |
| 2761 | BUG_ON(ret); |
| 2762 | cache->space_info = space_info; |
| 2763 | |
| 2764 | /* use EXTENT_LOCKED to prevent merging */ |
| 2765 | set_extent_bits(block_group_cache, found_key.objectid, |
| 2766 | found_key.objectid + found_key.offset - 1, |
| 2767 | bit | EXTENT_LOCKED, GFP_NOFS); |
| 2768 | set_state_private(block_group_cache, found_key.objectid, |
| 2769 | (unsigned long)cache); |
| 2770 | |
| 2771 | if (key.objectid >= |
| 2772 | btrfs_super_total_bytes(&info->super_copy)) |
| 2773 | break; |
| 2774 | } |
| 2775 | ret = 0; |
| 2776 | error: |
| 2777 | btrfs_free_path(path); |
| 2778 | return ret; |
| 2779 | } |
| 2780 | |
| 2781 | int btrfs_make_block_group(struct btrfs_trans_handle *trans, |
| 2782 | struct btrfs_root *root, u64 bytes_used, |
| 2783 | u64 type, u64 chunk_tree, u64 chunk_objectid, |
| 2784 | u64 size) |
| 2785 | { |
| 2786 | int ret; |
| 2787 | int bit = 0; |
| 2788 | struct btrfs_root *extent_root; |
| 2789 | struct btrfs_block_group_cache *cache; |
| 2790 | struct extent_io_tree *block_group_cache; |
| 2791 | |
| 2792 | extent_root = root->fs_info->extent_root; |
| 2793 | block_group_cache = &root->fs_info->block_group_cache; |
| 2794 | |
| 2795 | cache = kmalloc(sizeof(*cache), GFP_NOFS); |
| 2796 | BUG_ON(!cache); |
| 2797 | cache->key.objectid = chunk_objectid; |
| 2798 | cache->key.offset = size; |
| 2799 | cache->cached = 0; |
| 2800 | cache->pinned = 0; |
| 2801 | btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY); |
| 2802 | memset(&cache->item, 0, sizeof(cache->item)); |
| 2803 | btrfs_set_block_group_used(&cache->item, bytes_used); |
| 2804 | btrfs_set_block_group_chunk_tree(&cache->item, chunk_tree); |
| 2805 | btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid); |
| 2806 | cache->flags = type; |
| 2807 | btrfs_set_block_group_flags(&cache->item, type); |
| 2808 | |
| 2809 | ret = update_space_info(root->fs_info, cache->flags, size, bytes_used, |
| 2810 | &cache->space_info); |
| 2811 | BUG_ON(ret); |
| 2812 | |
| 2813 | if (type & BTRFS_BLOCK_GROUP_DATA) { |
| 2814 | bit = BLOCK_GROUP_DATA; |
| 2815 | } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 2816 | bit = BLOCK_GROUP_SYSTEM; |
| 2817 | } else if (type & BTRFS_BLOCK_GROUP_METADATA) { |
| 2818 | bit = BLOCK_GROUP_METADATA; |
| 2819 | } |
| 2820 | set_extent_bits(block_group_cache, chunk_objectid, |
| 2821 | chunk_objectid + size - 1, |
| 2822 | bit | EXTENT_LOCKED, GFP_NOFS); |
| 2823 | set_state_private(block_group_cache, chunk_objectid, |
| 2824 | (unsigned long)cache); |
| 2825 | |
| 2826 | ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item, |
| 2827 | sizeof(cache->item)); |
| 2828 | BUG_ON(ret); |
| 2829 | |
| 2830 | finish_current_insert(trans, extent_root); |
| 2831 | ret = del_pending_extents(trans, extent_root); |
| 2832 | BUG_ON(ret); |
| 2833 | return 0; |
| 2834 | } |