| 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 "ctree.h" |
| 21 | #include "disk-io.h" |
| 22 | #include "print-tree.h" |
| 23 | #include "transaction.h" |
| 24 | |
| 25 | static int finish_current_insert(struct btrfs_trans_handle *trans, struct |
| 26 | btrfs_root *extent_root); |
| 27 | static int del_pending_extents(struct btrfs_trans_handle *trans, struct |
| 28 | btrfs_root *extent_root); |
| 29 | |
| 30 | static int cache_block_group(struct btrfs_root *root, |
| 31 | struct btrfs_block_group_cache *block_group) |
| 32 | { |
| 33 | struct btrfs_path *path; |
| 34 | int ret; |
| 35 | struct btrfs_key key; |
| 36 | struct btrfs_leaf *leaf; |
| 37 | struct radix_tree_root *extent_radix; |
| 38 | int slot; |
| 39 | u64 i; |
| 40 | u64 last = 0; |
| 41 | u64 hole_size; |
| 42 | int found = 0; |
| 43 | |
| 44 | root = root->fs_info->extent_root; |
| 45 | extent_radix = &root->fs_info->extent_map_radix; |
| 46 | |
| 47 | if (block_group->cached) |
| 48 | return 0; |
| 49 | if (block_group->data) |
| 50 | return 0; |
| 51 | path = btrfs_alloc_path(); |
| 52 | if (!path) |
| 53 | return -ENOMEM; |
| 54 | path->reada = 2; |
| 55 | key.objectid = block_group->key.objectid; |
| 56 | key.flags = 0; |
| 57 | key.offset = 0; |
| 58 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 59 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 60 | if (ret < 0) |
| 61 | return ret; |
| 62 | if (ret && path->slots[0] > 0) |
| 63 | path->slots[0]--; |
| 64 | while(1) { |
| 65 | leaf = btrfs_buffer_leaf(path->nodes[0]); |
| 66 | slot = path->slots[0]; |
| 67 | if (slot >= btrfs_header_nritems(&leaf->header)) { |
| 68 | ret = btrfs_next_leaf(root, path); |
| 69 | if (ret < 0) |
| 70 | goto err; |
| 71 | if (ret == 0) { |
| 72 | continue; |
| 73 | } else { |
| 74 | if (found) { |
| 75 | hole_size = block_group->key.objectid + |
| 76 | block_group->key.offset - last; |
| 77 | } else { |
| 78 | last = block_group->key.objectid; |
| 79 | hole_size = block_group->key.offset; |
| 80 | } |
| 81 | for (i = 0; i < hole_size; i++) { |
| 82 | set_radix_bit(extent_radix, |
| 83 | last + i); |
| 84 | } |
| 85 | break; |
| 86 | } |
| 87 | } |
| 88 | btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key); |
| 89 | if (key.objectid >= block_group->key.objectid + |
| 90 | block_group->key.offset) { |
| 91 | if (found) { |
| 92 | hole_size = block_group->key.objectid + |
| 93 | block_group->key.offset - last; |
| 94 | } else { |
| 95 | last = block_group->key.objectid; |
| 96 | hole_size = block_group->key.offset; |
| 97 | } |
| 98 | for (i = 0; i < hole_size; i++) { |
| 99 | set_radix_bit(extent_radix, last + i); |
| 100 | } |
| 101 | break; |
| 102 | } |
| 103 | if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) { |
| 104 | if (!found) { |
| 105 | last = key.objectid + key.offset; |
| 106 | found = 1; |
| 107 | } else { |
| 108 | hole_size = key.objectid - last; |
| 109 | for (i = 0; i < hole_size; i++) { |
| 110 | set_radix_bit(extent_radix, last + i); |
| 111 | } |
| 112 | last = key.objectid + key.offset; |
| 113 | } |
| 114 | } |
| 115 | path->slots[0]++; |
| 116 | } |
| 117 | |
| 118 | block_group->cached = 1; |
| 119 | err: |
| 120 | btrfs_free_path(path); |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | struct btrfs_block_group_cache *btrfs_lookup_block_group(struct |
| 125 | btrfs_fs_info *info, |
| 126 | u64 blocknr) |
| 127 | { |
| 128 | struct btrfs_block_group_cache *block_group; |
| 129 | int ret; |
| 130 | |
| 131 | ret = radix_tree_gang_lookup(&info->block_group_radix, |
| 132 | (void **)&block_group, |
| 133 | blocknr, 1); |
| 134 | if (ret) { |
| 135 | if (block_group->key.objectid <= blocknr && blocknr <= |
| 136 | block_group->key.objectid + block_group->key.offset) |
| 137 | return block_group; |
| 138 | } |
| 139 | ret = radix_tree_gang_lookup(&info->block_group_data_radix, |
| 140 | (void **)&block_group, |
| 141 | blocknr, 1); |
| 142 | if (ret) { |
| 143 | if (block_group->key.objectid <= blocknr && blocknr <= |
| 144 | block_group->key.objectid + block_group->key.offset) |
| 145 | return block_group; |
| 146 | } |
| 147 | return NULL; |
| 148 | } |
| 149 | |
| 150 | static u64 leaf_range(struct btrfs_root *root) |
| 151 | { |
| 152 | u64 size = BTRFS_LEAF_DATA_SIZE(root); |
| 153 | do_div(size, sizeof(struct btrfs_extent_item) + |
| 154 | sizeof(struct btrfs_item)); |
| 155 | return size; |
| 156 | } |
| 157 | |
| 158 | static u64 find_search_start(struct btrfs_root *root, |
| 159 | struct btrfs_block_group_cache **cache_ret, |
| 160 | u64 search_start, int num) |
| 161 | { |
| 162 | unsigned long gang[8]; |
| 163 | int ret; |
| 164 | struct btrfs_block_group_cache *cache = *cache_ret; |
| 165 | u64 last = max(search_start, cache->key.objectid); |
| 166 | |
| 167 | if (cache->data) |
| 168 | goto out; |
| 169 | again: |
| 170 | ret = cache_block_group(root, cache); |
| 171 | if (ret) |
| 172 | goto out; |
| 173 | while(1) { |
| 174 | ret = find_first_radix_bit(&root->fs_info->extent_map_radix, |
| 175 | gang, last, ARRAY_SIZE(gang)); |
| 176 | if (!ret) |
| 177 | goto out; |
| 178 | last = gang[ret-1] + 1; |
| 179 | if (num > 1) { |
| 180 | if (ret != ARRAY_SIZE(gang)) { |
| 181 | goto new_group; |
| 182 | } |
| 183 | if (gang[ret-1] - gang[0] > leaf_range(root)) { |
| 184 | continue; |
| 185 | } |
| 186 | } |
| 187 | if (gang[0] >= cache->key.objectid + cache->key.offset) { |
| 188 | goto new_group; |
| 189 | } |
| 190 | return gang[0]; |
| 191 | } |
| 192 | out: |
| 193 | return max(cache->last_alloc, search_start); |
| 194 | |
| 195 | new_group: |
| 196 | cache = btrfs_lookup_block_group(root->fs_info, |
| 197 | last + cache->key.offset - 1); |
| 198 | if (!cache) { |
| 199 | return max((*cache_ret)->last_alloc, search_start); |
| 200 | } |
| 201 | cache = btrfs_find_block_group(root, cache, |
| 202 | last + cache->key.offset - 1, 0, 0); |
| 203 | *cache_ret = cache; |
| 204 | goto again; |
| 205 | } |
| 206 | |
| 207 | static u64 div_factor(u64 num, int factor) |
| 208 | { |
| 209 | num *= factor; |
| 210 | do_div(num, 10); |
| 211 | return num; |
| 212 | } |
| 213 | |
| 214 | struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root, |
| 215 | struct btrfs_block_group_cache |
| 216 | *hint, u64 search_start, |
| 217 | int data, int owner) |
| 218 | { |
| 219 | struct btrfs_block_group_cache *cache[8]; |
| 220 | struct btrfs_block_group_cache *found_group = NULL; |
| 221 | struct btrfs_fs_info *info = root->fs_info; |
| 222 | struct radix_tree_root *radix; |
| 223 | struct radix_tree_root *swap_radix; |
| 224 | u64 used; |
| 225 | u64 last = 0; |
| 226 | u64 hint_last; |
| 227 | int i; |
| 228 | int ret; |
| 229 | int full_search = 0; |
| 230 | int factor = 8; |
| 231 | int data_swap = 0; |
| 232 | |
| 233 | if (!owner) |
| 234 | factor = 5; |
| 235 | |
| 236 | if (data) { |
| 237 | radix = &info->block_group_data_radix; |
| 238 | swap_radix = &info->block_group_radix; |
| 239 | } else { |
| 240 | radix = &info->block_group_radix; |
| 241 | swap_radix = &info->block_group_data_radix; |
| 242 | } |
| 243 | |
| 244 | if (search_start) { |
| 245 | struct btrfs_block_group_cache *shint; |
| 246 | shint = btrfs_lookup_block_group(info, search_start); |
| 247 | if (shint->data == data) { |
| 248 | used = btrfs_block_group_used(&shint->item); |
| 249 | if (used + shint->pinned < |
| 250 | div_factor(shint->key.offset, factor)) { |
| 251 | return shint; |
| 252 | } |
| 253 | } |
| 254 | } |
| 255 | if (hint && hint->data == data) { |
| 256 | used = btrfs_block_group_used(&hint->item); |
| 257 | if (used + hint->pinned < |
| 258 | div_factor(hint->key.offset, factor)) { |
| 259 | return hint; |
| 260 | } |
| 261 | if (used >= div_factor(hint->key.offset, 8)) { |
| 262 | radix_tree_tag_clear(radix, |
| 263 | hint->key.objectid + |
| 264 | hint->key.offset - 1, |
| 265 | BTRFS_BLOCK_GROUP_AVAIL); |
| 266 | } |
| 267 | last = hint->key.offset * 3; |
| 268 | if (hint->key.objectid >= last) |
| 269 | last = max(search_start + hint->key.offset - 1, |
| 270 | hint->key.objectid - last); |
| 271 | else |
| 272 | last = hint->key.objectid + hint->key.offset; |
| 273 | hint_last = last; |
| 274 | } else { |
| 275 | if (hint) |
| 276 | hint_last = max(hint->key.objectid, search_start); |
| 277 | else |
| 278 | hint_last = search_start; |
| 279 | |
| 280 | last = hint_last; |
| 281 | } |
| 282 | while(1) { |
| 283 | ret = radix_tree_gang_lookup_tag(radix, (void **)cache, |
| 284 | last, ARRAY_SIZE(cache), |
| 285 | BTRFS_BLOCK_GROUP_AVAIL); |
| 286 | if (!ret) |
| 287 | break; |
| 288 | for (i = 0; i < ret; i++) { |
| 289 | last = cache[i]->key.objectid + |
| 290 | cache[i]->key.offset; |
| 291 | used = btrfs_block_group_used(&cache[i]->item); |
| 292 | if (used + cache[i]->pinned < |
| 293 | div_factor(cache[i]->key.offset, factor)) { |
| 294 | found_group = cache[i]; |
| 295 | goto found; |
| 296 | } |
| 297 | if (used >= div_factor(cache[i]->key.offset, 8)) { |
| 298 | radix_tree_tag_clear(radix, |
| 299 | cache[i]->key.objectid + |
| 300 | cache[i]->key.offset - 1, |
| 301 | BTRFS_BLOCK_GROUP_AVAIL); |
| 302 | } |
| 303 | } |
| 304 | cond_resched(); |
| 305 | } |
| 306 | last = hint_last; |
| 307 | again: |
| 308 | while(1) { |
| 309 | ret = radix_tree_gang_lookup(radix, (void **)cache, |
| 310 | last, ARRAY_SIZE(cache)); |
| 311 | if (!ret) |
| 312 | break; |
| 313 | for (i = 0; i < ret; i++) { |
| 314 | last = cache[i]->key.objectid + |
| 315 | cache[i]->key.offset; |
| 316 | used = btrfs_block_group_used(&cache[i]->item); |
| 317 | if (used + cache[i]->pinned < cache[i]->key.offset) { |
| 318 | found_group = cache[i]; |
| 319 | goto found; |
| 320 | } |
| 321 | if (used >= cache[i]->key.offset) { |
| 322 | radix_tree_tag_clear(radix, |
| 323 | cache[i]->key.objectid + |
| 324 | cache[i]->key.offset - 1, |
| 325 | BTRFS_BLOCK_GROUP_AVAIL); |
| 326 | } |
| 327 | } |
| 328 | cond_resched(); |
| 329 | } |
| 330 | if (!full_search) { |
| 331 | last = search_start; |
| 332 | full_search = 1; |
| 333 | goto again; |
| 334 | } |
| 335 | if (!data_swap) { |
| 336 | struct radix_tree_root *tmp = radix; |
| 337 | data_swap = 1; |
| 338 | radix = swap_radix; |
| 339 | swap_radix = tmp; |
| 340 | last = search_start; |
| 341 | goto again; |
| 342 | } |
| 343 | if (!found_group) { |
| 344 | ret = radix_tree_gang_lookup(radix, |
| 345 | (void **)&found_group, 0, 1); |
| 346 | if (ret == 0) { |
| 347 | ret = radix_tree_gang_lookup(swap_radix, |
| 348 | (void **)&found_group, |
| 349 | 0, 1); |
| 350 | } |
| 351 | BUG_ON(ret != 1); |
| 352 | } |
| 353 | found: |
| 354 | return found_group; |
| 355 | } |
| 356 | |
| 357 | int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, |
| 358 | struct btrfs_root *root, |
| 359 | u64 blocknr, u64 num_blocks) |
| 360 | { |
| 361 | struct btrfs_path *path; |
| 362 | int ret; |
| 363 | struct btrfs_key key; |
| 364 | struct btrfs_leaf *l; |
| 365 | struct btrfs_extent_item *item; |
| 366 | u32 refs; |
| 367 | |
| 368 | path = btrfs_alloc_path(); |
| 369 | if (!path) |
| 370 | return -ENOMEM; |
| 371 | |
| 372 | key.objectid = blocknr; |
| 373 | key.flags = 0; |
| 374 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 375 | key.offset = num_blocks; |
| 376 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, |
| 377 | 0, 1); |
| 378 | if (ret < 0) |
| 379 | return ret; |
| 380 | if (ret != 0) { |
| 381 | BUG(); |
| 382 | } |
| 383 | BUG_ON(ret != 0); |
| 384 | l = btrfs_buffer_leaf(path->nodes[0]); |
| 385 | item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); |
| 386 | refs = btrfs_extent_refs(item); |
| 387 | btrfs_set_extent_refs(item, refs + 1); |
| 388 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 389 | |
| 390 | btrfs_release_path(root->fs_info->extent_root, path); |
| 391 | btrfs_free_path(path); |
| 392 | finish_current_insert(trans, root->fs_info->extent_root); |
| 393 | del_pending_extents(trans, root->fs_info->extent_root); |
| 394 | return 0; |
| 395 | } |
| 396 | |
| 397 | int btrfs_extent_post_op(struct btrfs_trans_handle *trans, |
| 398 | struct btrfs_root *root) |
| 399 | { |
| 400 | finish_current_insert(trans, root->fs_info->extent_root); |
| 401 | del_pending_extents(trans, root->fs_info->extent_root); |
| 402 | return 0; |
| 403 | } |
| 404 | |
| 405 | static int lookup_extent_ref(struct btrfs_trans_handle *trans, |
| 406 | struct btrfs_root *root, u64 blocknr, |
| 407 | u64 num_blocks, u32 *refs) |
| 408 | { |
| 409 | struct btrfs_path *path; |
| 410 | int ret; |
| 411 | struct btrfs_key key; |
| 412 | struct btrfs_leaf *l; |
| 413 | struct btrfs_extent_item *item; |
| 414 | |
| 415 | path = btrfs_alloc_path(); |
| 416 | key.objectid = blocknr; |
| 417 | key.offset = num_blocks; |
| 418 | key.flags = 0; |
| 419 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 420 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, |
| 421 | 0, 0); |
| 422 | if (ret < 0) |
| 423 | goto out; |
| 424 | if (ret != 0) |
| 425 | BUG(); |
| 426 | l = btrfs_buffer_leaf(path->nodes[0]); |
| 427 | item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); |
| 428 | *refs = btrfs_extent_refs(item); |
| 429 | out: |
| 430 | btrfs_free_path(path); |
| 431 | return 0; |
| 432 | } |
| 433 | |
| 434 | int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, |
| 435 | struct btrfs_root *root) |
| 436 | { |
| 437 | return btrfs_inc_extent_ref(trans, root, bh_blocknr(root->node), 1); |
| 438 | } |
| 439 | |
| 440 | int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
| 441 | struct buffer_head *buf) |
| 442 | { |
| 443 | u64 blocknr; |
| 444 | struct btrfs_node *buf_node; |
| 445 | struct btrfs_leaf *buf_leaf; |
| 446 | struct btrfs_disk_key *key; |
| 447 | struct btrfs_file_extent_item *fi; |
| 448 | int i; |
| 449 | int leaf; |
| 450 | int ret; |
| 451 | int faili; |
| 452 | int err; |
| 453 | |
| 454 | if (!root->ref_cows) |
| 455 | return 0; |
| 456 | buf_node = btrfs_buffer_node(buf); |
| 457 | leaf = btrfs_is_leaf(buf_node); |
| 458 | buf_leaf = btrfs_buffer_leaf(buf); |
| 459 | for (i = 0; i < btrfs_header_nritems(&buf_node->header); i++) { |
| 460 | if (leaf) { |
| 461 | u64 disk_blocknr; |
| 462 | key = &buf_leaf->items[i].key; |
| 463 | if (btrfs_disk_key_type(key) != BTRFS_EXTENT_DATA_KEY) |
| 464 | continue; |
| 465 | fi = btrfs_item_ptr(buf_leaf, i, |
| 466 | struct btrfs_file_extent_item); |
| 467 | if (btrfs_file_extent_type(fi) == |
| 468 | BTRFS_FILE_EXTENT_INLINE) |
| 469 | continue; |
| 470 | disk_blocknr = btrfs_file_extent_disk_blocknr(fi); |
| 471 | if (disk_blocknr == 0) |
| 472 | continue; |
| 473 | ret = btrfs_inc_extent_ref(trans, root, disk_blocknr, |
| 474 | btrfs_file_extent_disk_num_blocks(fi)); |
| 475 | if (ret) { |
| 476 | faili = i; |
| 477 | goto fail; |
| 478 | } |
| 479 | } else { |
| 480 | blocknr = btrfs_node_blockptr(buf_node, i); |
| 481 | ret = btrfs_inc_extent_ref(trans, root, blocknr, 1); |
| 482 | if (ret) { |
| 483 | faili = i; |
| 484 | goto fail; |
| 485 | } |
| 486 | } |
| 487 | } |
| 488 | return 0; |
| 489 | fail: |
| 490 | WARN_ON(1); |
| 491 | for (i =0; i < faili; i++) { |
| 492 | if (leaf) { |
| 493 | u64 disk_blocknr; |
| 494 | key = &buf_leaf->items[i].key; |
| 495 | if (btrfs_disk_key_type(key) != BTRFS_EXTENT_DATA_KEY) |
| 496 | continue; |
| 497 | fi = btrfs_item_ptr(buf_leaf, i, |
| 498 | struct btrfs_file_extent_item); |
| 499 | if (btrfs_file_extent_type(fi) == |
| 500 | BTRFS_FILE_EXTENT_INLINE) |
| 501 | continue; |
| 502 | disk_blocknr = btrfs_file_extent_disk_blocknr(fi); |
| 503 | if (disk_blocknr == 0) |
| 504 | continue; |
| 505 | err = btrfs_free_extent(trans, root, disk_blocknr, |
| 506 | btrfs_file_extent_disk_num_blocks(fi), 0); |
| 507 | BUG_ON(err); |
| 508 | } else { |
| 509 | blocknr = btrfs_node_blockptr(buf_node, i); |
| 510 | err = btrfs_free_extent(trans, root, blocknr, 1, 0); |
| 511 | BUG_ON(err); |
| 512 | } |
| 513 | } |
| 514 | return ret; |
| 515 | } |
| 516 | |
| 517 | static int write_one_cache_group(struct btrfs_trans_handle *trans, |
| 518 | struct btrfs_root *root, |
| 519 | struct btrfs_path *path, |
| 520 | struct btrfs_block_group_cache *cache) |
| 521 | { |
| 522 | int ret; |
| 523 | int pending_ret; |
| 524 | struct btrfs_root *extent_root = root->fs_info->extent_root; |
| 525 | struct btrfs_block_group_item *bi; |
| 526 | |
| 527 | ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); |
| 528 | if (ret < 0) |
| 529 | goto fail; |
| 530 | BUG_ON(ret); |
| 531 | bi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0], |
| 532 | struct btrfs_block_group_item); |
| 533 | memcpy(bi, &cache->item, sizeof(*bi)); |
| 534 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 535 | btrfs_release_path(extent_root, path); |
| 536 | fail: |
| 537 | finish_current_insert(trans, extent_root); |
| 538 | pending_ret = del_pending_extents(trans, extent_root); |
| 539 | if (ret) |
| 540 | return ret; |
| 541 | if (pending_ret) |
| 542 | return pending_ret; |
| 543 | if (cache->data) |
| 544 | cache->last_alloc = cache->first_free; |
| 545 | return 0; |
| 546 | |
| 547 | } |
| 548 | |
| 549 | static int write_dirty_block_radix(struct btrfs_trans_handle *trans, |
| 550 | struct btrfs_root *root, |
| 551 | struct radix_tree_root *radix) |
| 552 | { |
| 553 | struct btrfs_block_group_cache *cache[8]; |
| 554 | int ret; |
| 555 | int err = 0; |
| 556 | int werr = 0; |
| 557 | int i; |
| 558 | struct btrfs_path *path; |
| 559 | unsigned long off = 0; |
| 560 | |
| 561 | path = btrfs_alloc_path(); |
| 562 | if (!path) |
| 563 | return -ENOMEM; |
| 564 | |
| 565 | while(1) { |
| 566 | ret = radix_tree_gang_lookup_tag(radix, (void **)cache, |
| 567 | off, ARRAY_SIZE(cache), |
| 568 | BTRFS_BLOCK_GROUP_DIRTY); |
| 569 | if (!ret) |
| 570 | break; |
| 571 | for (i = 0; i < ret; i++) { |
| 572 | err = write_one_cache_group(trans, root, |
| 573 | path, cache[i]); |
| 574 | /* |
| 575 | * if we fail to write the cache group, we want |
| 576 | * to keep it marked dirty in hopes that a later |
| 577 | * write will work |
| 578 | */ |
| 579 | if (err) { |
| 580 | werr = err; |
| 581 | off = cache[i]->key.objectid + |
| 582 | cache[i]->key.offset; |
| 583 | continue; |
| 584 | } |
| 585 | |
| 586 | radix_tree_tag_clear(radix, cache[i]->key.objectid + |
| 587 | cache[i]->key.offset - 1, |
| 588 | BTRFS_BLOCK_GROUP_DIRTY); |
| 589 | } |
| 590 | } |
| 591 | btrfs_free_path(path); |
| 592 | return werr; |
| 593 | } |
| 594 | |
| 595 | int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, |
| 596 | struct btrfs_root *root) |
| 597 | { |
| 598 | int ret; |
| 599 | int ret2; |
| 600 | ret = write_dirty_block_radix(trans, root, |
| 601 | &root->fs_info->block_group_radix); |
| 602 | ret2 = write_dirty_block_radix(trans, root, |
| 603 | &root->fs_info->block_group_data_radix); |
| 604 | if (ret) |
| 605 | return ret; |
| 606 | if (ret2) |
| 607 | return ret2; |
| 608 | return 0; |
| 609 | } |
| 610 | |
| 611 | static int update_block_group(struct btrfs_trans_handle *trans, |
| 612 | struct btrfs_root *root, |
| 613 | u64 blocknr, u64 num, int alloc, int mark_free, |
| 614 | int data) |
| 615 | { |
| 616 | struct btrfs_block_group_cache *cache; |
| 617 | struct btrfs_fs_info *info = root->fs_info; |
| 618 | u64 total = num; |
| 619 | u64 old_val; |
| 620 | u64 block_in_group; |
| 621 | u64 i; |
| 622 | int ret; |
| 623 | |
| 624 | while(total) { |
| 625 | cache = btrfs_lookup_block_group(info, blocknr); |
| 626 | if (!cache) { |
| 627 | return -1; |
| 628 | } |
| 629 | block_in_group = blocknr - cache->key.objectid; |
| 630 | WARN_ON(block_in_group > cache->key.offset); |
| 631 | radix_tree_tag_set(cache->radix, cache->key.objectid + |
| 632 | cache->key.offset - 1, |
| 633 | BTRFS_BLOCK_GROUP_DIRTY); |
| 634 | |
| 635 | old_val = btrfs_block_group_used(&cache->item); |
| 636 | num = min(total, cache->key.offset - block_in_group); |
| 637 | if (alloc) { |
| 638 | if (blocknr > cache->last_alloc) |
| 639 | cache->last_alloc = blocknr; |
| 640 | if (!cache->data) { |
| 641 | for (i = 0; i < num; i++) { |
| 642 | clear_radix_bit(&info->extent_map_radix, |
| 643 | blocknr + i); |
| 644 | } |
| 645 | } |
| 646 | if (cache->data != data && |
| 647 | old_val < (cache->key.offset >> 1)) { |
| 648 | cache->data = data; |
| 649 | radix_tree_delete(cache->radix, |
| 650 | cache->key.objectid + |
| 651 | cache->key.offset - 1); |
| 652 | |
| 653 | if (data) { |
| 654 | cache->radix = |
| 655 | &info->block_group_data_radix; |
| 656 | cache->item.flags |= |
| 657 | BTRFS_BLOCK_GROUP_DATA; |
| 658 | } else { |
| 659 | cache->radix = &info->block_group_radix; |
| 660 | cache->item.flags &= |
| 661 | ~BTRFS_BLOCK_GROUP_DATA; |
| 662 | } |
| 663 | ret = radix_tree_insert(cache->radix, |
| 664 | cache->key.objectid + |
| 665 | cache->key.offset - 1, |
| 666 | (void *)cache); |
| 667 | } |
| 668 | old_val += num; |
| 669 | } else { |
| 670 | old_val -= num; |
| 671 | if (blocknr < cache->first_free) |
| 672 | cache->first_free = blocknr; |
| 673 | if (!cache->data && mark_free) { |
| 674 | for (i = 0; i < num; i++) { |
| 675 | set_radix_bit(&info->extent_map_radix, |
| 676 | blocknr + i); |
| 677 | } |
| 678 | } |
| 679 | if (old_val < (cache->key.offset >> 1) && |
| 680 | old_val + num >= (cache->key.offset >> 1)) { |
| 681 | radix_tree_tag_set(cache->radix, |
| 682 | cache->key.objectid + |
| 683 | cache->key.offset - 1, |
| 684 | BTRFS_BLOCK_GROUP_AVAIL); |
| 685 | } |
| 686 | } |
| 687 | btrfs_set_block_group_used(&cache->item, old_val); |
| 688 | total -= num; |
| 689 | blocknr += num; |
| 690 | } |
| 691 | return 0; |
| 692 | } |
| 693 | |
| 694 | int btrfs_copy_pinned(struct btrfs_root *root, struct radix_tree_root *copy) |
| 695 | { |
| 696 | unsigned long gang[8]; |
| 697 | u64 last = 0; |
| 698 | struct radix_tree_root *pinned_radix = &root->fs_info->pinned_radix; |
| 699 | int ret; |
| 700 | int i; |
| 701 | |
| 702 | while(1) { |
| 703 | ret = find_first_radix_bit(pinned_radix, gang, last, |
| 704 | ARRAY_SIZE(gang)); |
| 705 | if (!ret) |
| 706 | break; |
| 707 | for (i = 0 ; i < ret; i++) { |
| 708 | set_radix_bit(copy, gang[i]); |
| 709 | last = gang[i] + 1; |
| 710 | } |
| 711 | } |
| 712 | ret = find_first_radix_bit(&root->fs_info->extent_ins_radix, gang, 0, |
| 713 | ARRAY_SIZE(gang)); |
| 714 | WARN_ON(ret); |
| 715 | return 0; |
| 716 | } |
| 717 | |
| 718 | int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, |
| 719 | struct btrfs_root *root, |
| 720 | struct radix_tree_root *unpin_radix) |
| 721 | { |
| 722 | unsigned long gang[8]; |
| 723 | struct btrfs_block_group_cache *block_group; |
| 724 | u64 first = 0; |
| 725 | int ret; |
| 726 | int i; |
| 727 | struct radix_tree_root *pinned_radix = &root->fs_info->pinned_radix; |
| 728 | struct radix_tree_root *extent_radix = &root->fs_info->extent_map_radix; |
| 729 | |
| 730 | while(1) { |
| 731 | ret = find_first_radix_bit(unpin_radix, gang, 0, |
| 732 | ARRAY_SIZE(gang)); |
| 733 | if (!ret) |
| 734 | break; |
| 735 | if (!first) |
| 736 | first = gang[0]; |
| 737 | for (i = 0; i < ret; i++) { |
| 738 | clear_radix_bit(pinned_radix, gang[i]); |
| 739 | clear_radix_bit(unpin_radix, gang[i]); |
| 740 | block_group = btrfs_lookup_block_group(root->fs_info, |
| 741 | gang[i]); |
| 742 | if (block_group) { |
| 743 | WARN_ON(block_group->pinned == 0); |
| 744 | block_group->pinned--; |
| 745 | if (gang[i] < block_group->last_alloc) |
| 746 | block_group->last_alloc = gang[i]; |
| 747 | if (!block_group->data) |
| 748 | set_radix_bit(extent_radix, gang[i]); |
| 749 | } |
| 750 | } |
| 751 | } |
| 752 | return 0; |
| 753 | } |
| 754 | |
| 755 | static int finish_current_insert(struct btrfs_trans_handle *trans, struct |
| 756 | btrfs_root *extent_root) |
| 757 | { |
| 758 | struct btrfs_key ins; |
| 759 | struct btrfs_extent_item extent_item; |
| 760 | int i; |
| 761 | int ret; |
| 762 | int err; |
| 763 | unsigned long gang[8]; |
| 764 | struct btrfs_fs_info *info = extent_root->fs_info; |
| 765 | |
| 766 | btrfs_set_extent_refs(&extent_item, 1); |
| 767 | ins.offset = 1; |
| 768 | ins.flags = 0; |
| 769 | btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY); |
| 770 | btrfs_set_extent_owner(&extent_item, extent_root->root_key.objectid); |
| 771 | |
| 772 | while(1) { |
| 773 | ret = find_first_radix_bit(&info->extent_ins_radix, gang, 0, |
| 774 | ARRAY_SIZE(gang)); |
| 775 | if (!ret) |
| 776 | break; |
| 777 | |
| 778 | for (i = 0; i < ret; i++) { |
| 779 | ins.objectid = gang[i]; |
| 780 | err = btrfs_insert_item(trans, extent_root, &ins, |
| 781 | &extent_item, |
| 782 | sizeof(extent_item)); |
| 783 | clear_radix_bit(&info->extent_ins_radix, gang[i]); |
| 784 | WARN_ON(err); |
| 785 | } |
| 786 | } |
| 787 | return 0; |
| 788 | } |
| 789 | |
| 790 | static int pin_down_block(struct btrfs_root *root, u64 blocknr, int pending) |
| 791 | { |
| 792 | int err; |
| 793 | struct btrfs_header *header; |
| 794 | struct buffer_head *bh; |
| 795 | |
| 796 | if (!pending) { |
| 797 | bh = btrfs_find_tree_block(root, blocknr); |
| 798 | if (bh) { |
| 799 | if (buffer_uptodate(bh)) { |
| 800 | u64 transid = |
| 801 | root->fs_info->running_transaction->transid; |
| 802 | header = btrfs_buffer_header(bh); |
| 803 | if (btrfs_header_generation(header) == |
| 804 | transid) { |
| 805 | btrfs_block_release(root, bh); |
| 806 | return 0; |
| 807 | } |
| 808 | } |
| 809 | btrfs_block_release(root, bh); |
| 810 | } |
| 811 | err = set_radix_bit(&root->fs_info->pinned_radix, blocknr); |
| 812 | if (!err) { |
| 813 | struct btrfs_block_group_cache *cache; |
| 814 | cache = btrfs_lookup_block_group(root->fs_info, |
| 815 | blocknr); |
| 816 | if (cache) |
| 817 | cache->pinned++; |
| 818 | } |
| 819 | } else { |
| 820 | err = set_radix_bit(&root->fs_info->pending_del_radix, blocknr); |
| 821 | } |
| 822 | BUG_ON(err < 0); |
| 823 | return 0; |
| 824 | } |
| 825 | |
| 826 | /* |
| 827 | * remove an extent from the root, returns 0 on success |
| 828 | */ |
| 829 | static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 830 | *root, u64 blocknr, u64 num_blocks, int pin, |
| 831 | int mark_free) |
| 832 | { |
| 833 | struct btrfs_path *path; |
| 834 | struct btrfs_key key; |
| 835 | struct btrfs_fs_info *info = root->fs_info; |
| 836 | struct btrfs_root *extent_root = info->extent_root; |
| 837 | int ret; |
| 838 | struct btrfs_extent_item *ei; |
| 839 | u32 refs; |
| 840 | |
| 841 | key.objectid = blocknr; |
| 842 | key.flags = 0; |
| 843 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); |
| 844 | key.offset = num_blocks; |
| 845 | |
| 846 | path = btrfs_alloc_path(); |
| 847 | if (!path) |
| 848 | return -ENOMEM; |
| 849 | |
| 850 | ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); |
| 851 | if (ret < 0) |
| 852 | return ret; |
| 853 | BUG_ON(ret); |
| 854 | ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0], |
| 855 | struct btrfs_extent_item); |
| 856 | BUG_ON(ei->refs == 0); |
| 857 | refs = btrfs_extent_refs(ei) - 1; |
| 858 | btrfs_set_extent_refs(ei, refs); |
| 859 | btrfs_mark_buffer_dirty(path->nodes[0]); |
| 860 | if (refs == 0) { |
| 861 | u64 super_blocks_used; |
| 862 | |
| 863 | if (pin) { |
| 864 | ret = pin_down_block(root, blocknr, 0); |
| 865 | BUG_ON(ret); |
| 866 | } |
| 867 | |
| 868 | super_blocks_used = btrfs_super_blocks_used(&info->super_copy); |
| 869 | btrfs_set_super_blocks_used(&info->super_copy, |
| 870 | super_blocks_used - num_blocks); |
| 871 | ret = btrfs_del_item(trans, extent_root, path); |
| 872 | if (ret) { |
| 873 | return ret; |
| 874 | } |
| 875 | ret = update_block_group(trans, root, blocknr, num_blocks, 0, |
| 876 | mark_free, 0); |
| 877 | BUG_ON(ret); |
| 878 | } |
| 879 | btrfs_free_path(path); |
| 880 | finish_current_insert(trans, extent_root); |
| 881 | return ret; |
| 882 | } |
| 883 | |
| 884 | /* |
| 885 | * find all the blocks marked as pending in the radix tree and remove |
| 886 | * them from the extent map |
| 887 | */ |
| 888 | static int del_pending_extents(struct btrfs_trans_handle *trans, struct |
| 889 | btrfs_root *extent_root) |
| 890 | { |
| 891 | int ret; |
| 892 | int wret; |
| 893 | int err = 0; |
| 894 | unsigned long gang[4]; |
| 895 | int i; |
| 896 | struct radix_tree_root *pending_radix; |
| 897 | struct radix_tree_root *pinned_radix; |
| 898 | struct btrfs_block_group_cache *cache; |
| 899 | |
| 900 | pending_radix = &extent_root->fs_info->pending_del_radix; |
| 901 | pinned_radix = &extent_root->fs_info->pinned_radix; |
| 902 | |
| 903 | while(1) { |
| 904 | ret = find_first_radix_bit(pending_radix, gang, 0, |
| 905 | ARRAY_SIZE(gang)); |
| 906 | if (!ret) |
| 907 | break; |
| 908 | for (i = 0; i < ret; i++) { |
| 909 | wret = set_radix_bit(pinned_radix, gang[i]); |
| 910 | if (wret == 0) { |
| 911 | cache = |
| 912 | btrfs_lookup_block_group(extent_root->fs_info, |
| 913 | gang[i]); |
| 914 | if (cache) |
| 915 | cache->pinned++; |
| 916 | } |
| 917 | if (wret < 0) { |
| 918 | printk(KERN_CRIT "set_radix_bit, err %d\n", |
| 919 | wret); |
| 920 | BUG_ON(wret < 0); |
| 921 | } |
| 922 | wret = clear_radix_bit(pending_radix, gang[i]); |
| 923 | BUG_ON(wret); |
| 924 | wret = __free_extent(trans, extent_root, |
| 925 | gang[i], 1, 0, 0); |
| 926 | if (wret) |
| 927 | err = wret; |
| 928 | } |
| 929 | } |
| 930 | return err; |
| 931 | } |
| 932 | |
| 933 | /* |
| 934 | * remove an extent from the root, returns 0 on success |
| 935 | */ |
| 936 | int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 937 | *root, u64 blocknr, u64 num_blocks, int pin) |
| 938 | { |
| 939 | struct btrfs_root *extent_root = root->fs_info->extent_root; |
| 940 | int pending_ret; |
| 941 | int ret; |
| 942 | |
| 943 | if (root == extent_root) { |
| 944 | pin_down_block(root, blocknr, 1); |
| 945 | return 0; |
| 946 | } |
| 947 | ret = __free_extent(trans, root, blocknr, num_blocks, pin, pin == 0); |
| 948 | pending_ret = del_pending_extents(trans, root->fs_info->extent_root); |
| 949 | return ret ? ret : pending_ret; |
| 950 | } |
| 951 | |
| 952 | /* |
| 953 | * walks the btree of allocated extents and find a hole of a given size. |
| 954 | * The key ins is changed to record the hole: |
| 955 | * ins->objectid == block start |
| 956 | * ins->flags = BTRFS_EXTENT_ITEM_KEY |
| 957 | * ins->offset == number of blocks |
| 958 | * Any available blocks before search_start are skipped. |
| 959 | */ |
| 960 | static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root |
| 961 | *orig_root, u64 num_blocks, u64 empty_size, |
| 962 | u64 search_start, u64 search_end, u64 hint_block, |
| 963 | struct btrfs_key *ins, u64 exclude_start, |
| 964 | u64 exclude_nr, int data) |
| 965 | { |
| 966 | struct btrfs_path *path; |
| 967 | struct btrfs_key key; |
| 968 | int ret; |
| 969 | u64 hole_size = 0; |
| 970 | int slot = 0; |
| 971 | u64 last_block = 0; |
| 972 | u64 test_block; |
| 973 | u64 orig_search_start = search_start; |
| 974 | int start_found; |
| 975 | struct btrfs_leaf *l; |
| 976 | struct btrfs_root * root = orig_root->fs_info->extent_root; |
| 977 | struct btrfs_fs_info *info = root->fs_info; |
| 978 | int total_needed = num_blocks; |
| 979 | int level; |
| 980 | struct btrfs_block_group_cache *block_group; |
| 981 | int full_scan = 0; |
| 982 | int wrapped = 0; |
| 983 | |
| 984 | WARN_ON(num_blocks < 1); |
| 985 | ins->flags = 0; |
| 986 | btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); |
| 987 | |
| 988 | level = btrfs_header_level(btrfs_buffer_header(root->node)); |
| 989 | if (search_end == (u64)-1) |
| 990 | search_end = btrfs_super_total_blocks(&info->super_copy); |
| 991 | if (hint_block) { |
| 992 | block_group = btrfs_lookup_block_group(info, hint_block); |
| 993 | block_group = btrfs_find_block_group(root, block_group, |
| 994 | hint_block, data, 1); |
| 995 | } else { |
| 996 | block_group = btrfs_find_block_group(root, |
| 997 | trans->block_group, 0, |
| 998 | data, 1); |
| 999 | } |
| 1000 | |
| 1001 | total_needed += empty_size; |
| 1002 | path = btrfs_alloc_path(); |
| 1003 | |
| 1004 | check_failed: |
| 1005 | if (!block_group->data) |
| 1006 | search_start = find_search_start(root, &block_group, |
| 1007 | search_start, total_needed); |
| 1008 | else if (!full_scan) |
| 1009 | search_start = max(block_group->last_alloc, search_start); |
| 1010 | |
| 1011 | btrfs_init_path(path); |
| 1012 | ins->objectid = search_start; |
| 1013 | ins->offset = 0; |
| 1014 | start_found = 0; |
| 1015 | path->reada = 2; |
| 1016 | |
| 1017 | ret = btrfs_search_slot(trans, root, ins, path, 0, 0); |
| 1018 | if (ret < 0) |
| 1019 | goto error; |
| 1020 | |
| 1021 | if (path->slots[0] > 0) { |
| 1022 | path->slots[0]--; |
| 1023 | } |
| 1024 | |
| 1025 | l = btrfs_buffer_leaf(path->nodes[0]); |
| 1026 | btrfs_disk_key_to_cpu(&key, &l->items[path->slots[0]].key); |
| 1027 | /* |
| 1028 | * a rare case, go back one key if we hit a block group item |
| 1029 | * instead of an extent item |
| 1030 | */ |
| 1031 | if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY && |
| 1032 | key.objectid + key.offset >= search_start) { |
| 1033 | ins->objectid = key.objectid; |
| 1034 | ins->offset = key.offset - 1; |
| 1035 | btrfs_release_path(root, path); |
| 1036 | ret = btrfs_search_slot(trans, root, ins, path, 0, 0); |
| 1037 | if (ret < 0) |
| 1038 | goto error; |
| 1039 | |
| 1040 | if (path->slots[0] > 0) { |
| 1041 | path->slots[0]--; |
| 1042 | } |
| 1043 | } |
| 1044 | |
| 1045 | while (1) { |
| 1046 | l = btrfs_buffer_leaf(path->nodes[0]); |
| 1047 | slot = path->slots[0]; |
| 1048 | if (slot >= btrfs_header_nritems(&l->header)) { |
| 1049 | ret = btrfs_next_leaf(root, path); |
| 1050 | if (ret == 0) |
| 1051 | continue; |
| 1052 | if (ret < 0) |
| 1053 | goto error; |
| 1054 | if (!start_found) { |
| 1055 | ins->objectid = search_start; |
| 1056 | ins->offset = search_end - search_start; |
| 1057 | start_found = 1; |
| 1058 | goto check_pending; |
| 1059 | } |
| 1060 | ins->objectid = last_block > search_start ? |
| 1061 | last_block : search_start; |
| 1062 | ins->offset = search_end - ins->objectid; |
| 1063 | goto check_pending; |
| 1064 | } |
| 1065 | |
| 1066 | btrfs_disk_key_to_cpu(&key, &l->items[slot].key); |
| 1067 | if (key.objectid >= search_start && key.objectid > last_block && |
| 1068 | start_found) { |
| 1069 | if (last_block < search_start) |
| 1070 | last_block = search_start; |
| 1071 | hole_size = key.objectid - last_block; |
| 1072 | if (hole_size >= num_blocks) { |
| 1073 | ins->objectid = last_block; |
| 1074 | ins->offset = hole_size; |
| 1075 | goto check_pending; |
| 1076 | } |
| 1077 | } |
| 1078 | |
| 1079 | if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY) |
| 1080 | goto next; |
| 1081 | |
| 1082 | start_found = 1; |
| 1083 | last_block = key.objectid + key.offset; |
| 1084 | if (!full_scan && last_block >= block_group->key.objectid + |
| 1085 | block_group->key.offset) { |
| 1086 | btrfs_release_path(root, path); |
| 1087 | search_start = block_group->key.objectid + |
| 1088 | block_group->key.offset * 2; |
| 1089 | goto new_group; |
| 1090 | } |
| 1091 | next: |
| 1092 | path->slots[0]++; |
| 1093 | cond_resched(); |
| 1094 | } |
| 1095 | check_pending: |
| 1096 | /* we have to make sure we didn't find an extent that has already |
| 1097 | * been allocated by the map tree or the original allocation |
| 1098 | */ |
| 1099 | btrfs_release_path(root, path); |
| 1100 | BUG_ON(ins->objectid < search_start); |
| 1101 | |
| 1102 | if (ins->objectid + num_blocks >= search_end) { |
| 1103 | if (full_scan) { |
| 1104 | ret = -ENOSPC; |
| 1105 | goto error; |
| 1106 | } |
| 1107 | search_start = orig_search_start; |
| 1108 | if (wrapped) { |
| 1109 | if (!full_scan) |
| 1110 | total_needed -= empty_size; |
| 1111 | full_scan = 1; |
| 1112 | } else |
| 1113 | wrapped = 1; |
| 1114 | goto new_group; |
| 1115 | } |
| 1116 | for (test_block = ins->objectid; |
| 1117 | test_block < ins->objectid + num_blocks; test_block++) { |
| 1118 | if (test_radix_bit(&info->pinned_radix, test_block) || |
| 1119 | test_radix_bit(&info->extent_ins_radix, test_block)) { |
| 1120 | search_start = test_block + 1; |
| 1121 | goto new_group; |
| 1122 | } |
| 1123 | } |
| 1124 | if (exclude_nr > 0 && (ins->objectid + num_blocks > exclude_start && |
| 1125 | ins->objectid < exclude_start + exclude_nr)) { |
| 1126 | search_start = exclude_start + exclude_nr; |
| 1127 | goto new_group; |
| 1128 | } |
| 1129 | if (!data) { |
| 1130 | block_group = btrfs_lookup_block_group(info, ins->objectid); |
| 1131 | if (block_group) |
| 1132 | trans->block_group = block_group; |
| 1133 | } |
| 1134 | ins->offset = num_blocks; |
| 1135 | btrfs_free_path(path); |
| 1136 | return 0; |
| 1137 | |
| 1138 | new_group: |
| 1139 | if (search_start + num_blocks >= search_end) { |
| 1140 | search_start = orig_search_start; |
| 1141 | if (full_scan) { |
| 1142 | ret = -ENOSPC; |
| 1143 | goto error; |
| 1144 | } |
| 1145 | if (wrapped) { |
| 1146 | if (!full_scan) |
| 1147 | total_needed -= empty_size; |
| 1148 | full_scan = 1; |
| 1149 | } else |
| 1150 | wrapped = 1; |
| 1151 | } |
| 1152 | block_group = btrfs_lookup_block_group(info, search_start); |
| 1153 | cond_resched(); |
| 1154 | if (!full_scan) |
| 1155 | block_group = btrfs_find_block_group(root, block_group, |
| 1156 | search_start, data, 0); |
| 1157 | goto check_failed; |
| 1158 | |
| 1159 | error: |
| 1160 | btrfs_release_path(root, path); |
| 1161 | btrfs_free_path(path); |
| 1162 | return ret; |
| 1163 | } |
| 1164 | /* |
| 1165 | * finds a free extent and does all the dirty work required for allocation |
| 1166 | * returns the key for the extent through ins, and a tree buffer for |
| 1167 | * the first block of the extent through buf. |
| 1168 | * |
| 1169 | * returns 0 if everything worked, non-zero otherwise. |
| 1170 | */ |
| 1171 | int btrfs_alloc_extent(struct btrfs_trans_handle *trans, |
| 1172 | struct btrfs_root *root, u64 owner, |
| 1173 | u64 num_blocks, u64 empty_size, u64 hint_block, |
| 1174 | u64 search_end, struct btrfs_key *ins, int data) |
| 1175 | { |
| 1176 | int ret; |
| 1177 | int pending_ret; |
| 1178 | u64 super_blocks_used; |
| 1179 | u64 search_start = 0; |
| 1180 | struct btrfs_fs_info *info = root->fs_info; |
| 1181 | struct btrfs_root *extent_root = info->extent_root; |
| 1182 | struct btrfs_extent_item extent_item; |
| 1183 | |
| 1184 | btrfs_set_extent_refs(&extent_item, 1); |
| 1185 | btrfs_set_extent_owner(&extent_item, owner); |
| 1186 | |
| 1187 | WARN_ON(num_blocks < 1); |
| 1188 | ret = find_free_extent(trans, root, num_blocks, empty_size, |
| 1189 | search_start, search_end, hint_block, ins, |
| 1190 | trans->alloc_exclude_start, |
| 1191 | trans->alloc_exclude_nr, data); |
| 1192 | BUG_ON(ret); |
| 1193 | if (ret) |
| 1194 | return ret; |
| 1195 | |
| 1196 | super_blocks_used = btrfs_super_blocks_used(&info->super_copy); |
| 1197 | btrfs_set_super_blocks_used(&info->super_copy, super_blocks_used + |
| 1198 | num_blocks); |
| 1199 | |
| 1200 | if (root == extent_root) { |
| 1201 | BUG_ON(num_blocks != 1); |
| 1202 | set_radix_bit(&root->fs_info->extent_ins_radix, ins->objectid); |
| 1203 | goto update_block; |
| 1204 | } |
| 1205 | |
| 1206 | WARN_ON(trans->alloc_exclude_nr); |
| 1207 | trans->alloc_exclude_start = ins->objectid; |
| 1208 | trans->alloc_exclude_nr = ins->offset; |
| 1209 | ret = btrfs_insert_item(trans, extent_root, ins, &extent_item, |
| 1210 | sizeof(extent_item)); |
| 1211 | |
| 1212 | trans->alloc_exclude_start = 0; |
| 1213 | trans->alloc_exclude_nr = 0; |
| 1214 | |
| 1215 | BUG_ON(ret); |
| 1216 | finish_current_insert(trans, extent_root); |
| 1217 | pending_ret = del_pending_extents(trans, extent_root); |
| 1218 | if (ret) { |
| 1219 | return ret; |
| 1220 | } |
| 1221 | if (pending_ret) { |
| 1222 | return pending_ret; |
| 1223 | } |
| 1224 | |
| 1225 | update_block: |
| 1226 | ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0, |
| 1227 | data); |
| 1228 | BUG_ON(ret); |
| 1229 | return 0; |
| 1230 | } |
| 1231 | |
| 1232 | /* |
| 1233 | * helper function to allocate a block for a given tree |
| 1234 | * returns the tree buffer or NULL. |
| 1235 | */ |
| 1236 | struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, |
| 1237 | struct btrfs_root *root, u64 hint, |
| 1238 | u64 empty_size) |
| 1239 | { |
| 1240 | struct btrfs_key ins; |
| 1241 | int ret; |
| 1242 | struct buffer_head *buf; |
| 1243 | |
| 1244 | ret = btrfs_alloc_extent(trans, root, root->root_key.objectid, |
| 1245 | 1, empty_size, hint, |
| 1246 | (unsigned long)-1, &ins, 0); |
| 1247 | if (ret) { |
| 1248 | BUG_ON(ret > 0); |
| 1249 | return ERR_PTR(ret); |
| 1250 | } |
| 1251 | buf = btrfs_find_create_tree_block(root, ins.objectid); |
| 1252 | if (!buf) { |
| 1253 | btrfs_free_extent(trans, root, ins.objectid, 1, 0); |
| 1254 | return ERR_PTR(-ENOMEM); |
| 1255 | } |
| 1256 | WARN_ON(buffer_dirty(buf)); |
| 1257 | set_buffer_uptodate(buf); |
| 1258 | set_buffer_checked(buf); |
| 1259 | set_buffer_defrag(buf); |
| 1260 | set_radix_bit(&trans->transaction->dirty_pages, buf->b_page->index); |
| 1261 | return buf; |
| 1262 | } |
| 1263 | |
| 1264 | static int drop_leaf_ref(struct btrfs_trans_handle *trans, |
| 1265 | struct btrfs_root *root, struct buffer_head *cur) |
| 1266 | { |
| 1267 | struct btrfs_disk_key *key; |
| 1268 | struct btrfs_leaf *leaf; |
| 1269 | struct btrfs_file_extent_item *fi; |
| 1270 | int i; |
| 1271 | int nritems; |
| 1272 | int ret; |
| 1273 | |
| 1274 | BUG_ON(!btrfs_is_leaf(btrfs_buffer_node(cur))); |
| 1275 | leaf = btrfs_buffer_leaf(cur); |
| 1276 | nritems = btrfs_header_nritems(&leaf->header); |
| 1277 | for (i = 0; i < nritems; i++) { |
| 1278 | u64 disk_blocknr; |
| 1279 | key = &leaf->items[i].key; |
| 1280 | if (btrfs_disk_key_type(key) != BTRFS_EXTENT_DATA_KEY) |
| 1281 | continue; |
| 1282 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); |
| 1283 | if (btrfs_file_extent_type(fi) == BTRFS_FILE_EXTENT_INLINE) |
| 1284 | continue; |
| 1285 | /* |
| 1286 | * FIXME make sure to insert a trans record that |
| 1287 | * repeats the snapshot del on crash |
| 1288 | */ |
| 1289 | disk_blocknr = btrfs_file_extent_disk_blocknr(fi); |
| 1290 | if (disk_blocknr == 0) |
| 1291 | continue; |
| 1292 | ret = btrfs_free_extent(trans, root, disk_blocknr, |
| 1293 | btrfs_file_extent_disk_num_blocks(fi), |
| 1294 | 0); |
| 1295 | BUG_ON(ret); |
| 1296 | } |
| 1297 | return 0; |
| 1298 | } |
| 1299 | |
| 1300 | static void reada_walk_down(struct btrfs_root *root, |
| 1301 | struct btrfs_node *node) |
| 1302 | { |
| 1303 | int i; |
| 1304 | u32 nritems; |
| 1305 | u64 blocknr; |
| 1306 | int ret; |
| 1307 | u32 refs; |
| 1308 | |
| 1309 | nritems = btrfs_header_nritems(&node->header); |
| 1310 | for (i = 0; i < nritems; i++) { |
| 1311 | blocknr = btrfs_node_blockptr(node, i); |
| 1312 | ret = lookup_extent_ref(NULL, root, blocknr, 1, &refs); |
| 1313 | BUG_ON(ret); |
| 1314 | if (refs != 1) |
| 1315 | continue; |
| 1316 | mutex_unlock(&root->fs_info->fs_mutex); |
| 1317 | ret = readahead_tree_block(root, blocknr); |
| 1318 | cond_resched(); |
| 1319 | mutex_lock(&root->fs_info->fs_mutex); |
| 1320 | if (ret) |
| 1321 | break; |
| 1322 | } |
| 1323 | } |
| 1324 | |
| 1325 | /* |
| 1326 | * helper function for drop_snapshot, this walks down the tree dropping ref |
| 1327 | * counts as it goes. |
| 1328 | */ |
| 1329 | static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root |
| 1330 | *root, struct btrfs_path *path, int *level) |
| 1331 | { |
| 1332 | struct buffer_head *next; |
| 1333 | struct buffer_head *cur; |
| 1334 | u64 blocknr; |
| 1335 | int ret; |
| 1336 | u32 refs; |
| 1337 | |
| 1338 | WARN_ON(*level < 0); |
| 1339 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 1340 | ret = lookup_extent_ref(trans, root, bh_blocknr(path->nodes[*level]), |
| 1341 | 1, &refs); |
| 1342 | BUG_ON(ret); |
| 1343 | if (refs > 1) |
| 1344 | goto out; |
| 1345 | |
| 1346 | /* |
| 1347 | * walk down to the last node level and free all the leaves |
| 1348 | */ |
| 1349 | while(*level >= 0) { |
| 1350 | WARN_ON(*level < 0); |
| 1351 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 1352 | cur = path->nodes[*level]; |
| 1353 | |
| 1354 | if (*level > 0 && path->slots[*level] == 0) |
| 1355 | reada_walk_down(root, btrfs_buffer_node(cur)); |
| 1356 | |
| 1357 | if (btrfs_header_level(btrfs_buffer_header(cur)) != *level) |
| 1358 | WARN_ON(1); |
| 1359 | |
| 1360 | if (path->slots[*level] >= |
| 1361 | btrfs_header_nritems(btrfs_buffer_header(cur))) |
| 1362 | break; |
| 1363 | if (*level == 0) { |
| 1364 | ret = drop_leaf_ref(trans, root, cur); |
| 1365 | BUG_ON(ret); |
| 1366 | break; |
| 1367 | } |
| 1368 | blocknr = btrfs_node_blockptr(btrfs_buffer_node(cur), |
| 1369 | path->slots[*level]); |
| 1370 | ret = lookup_extent_ref(trans, root, blocknr, 1, &refs); |
| 1371 | BUG_ON(ret); |
| 1372 | if (refs != 1) { |
| 1373 | path->slots[*level]++; |
| 1374 | ret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
| 1375 | BUG_ON(ret); |
| 1376 | continue; |
| 1377 | } |
| 1378 | next = btrfs_find_tree_block(root, blocknr); |
| 1379 | if (!next || !buffer_uptodate(next)) { |
| 1380 | brelse(next); |
| 1381 | mutex_unlock(&root->fs_info->fs_mutex); |
| 1382 | next = read_tree_block(root, blocknr); |
| 1383 | mutex_lock(&root->fs_info->fs_mutex); |
| 1384 | |
| 1385 | /* we dropped the lock, check one more time */ |
| 1386 | ret = lookup_extent_ref(trans, root, blocknr, 1, &refs); |
| 1387 | BUG_ON(ret); |
| 1388 | if (refs != 1) { |
| 1389 | path->slots[*level]++; |
| 1390 | brelse(next); |
| 1391 | ret = btrfs_free_extent(trans, root, |
| 1392 | blocknr, 1, 1); |
| 1393 | BUG_ON(ret); |
| 1394 | continue; |
| 1395 | } |
| 1396 | } |
| 1397 | WARN_ON(*level <= 0); |
| 1398 | if (path->nodes[*level-1]) |
| 1399 | btrfs_block_release(root, path->nodes[*level-1]); |
| 1400 | path->nodes[*level-1] = next; |
| 1401 | *level = btrfs_header_level(btrfs_buffer_header(next)); |
| 1402 | path->slots[*level] = 0; |
| 1403 | } |
| 1404 | out: |
| 1405 | WARN_ON(*level < 0); |
| 1406 | WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| 1407 | ret = btrfs_free_extent(trans, root, |
| 1408 | bh_blocknr(path->nodes[*level]), 1, 1); |
| 1409 | btrfs_block_release(root, path->nodes[*level]); |
| 1410 | path->nodes[*level] = NULL; |
| 1411 | *level += 1; |
| 1412 | BUG_ON(ret); |
| 1413 | return 0; |
| 1414 | } |
| 1415 | |
| 1416 | /* |
| 1417 | * helper for dropping snapshots. This walks back up the tree in the path |
| 1418 | * to find the first node higher up where we haven't yet gone through |
| 1419 | * all the slots |
| 1420 | */ |
| 1421 | static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root |
| 1422 | *root, struct btrfs_path *path, int *level) |
| 1423 | { |
| 1424 | int i; |
| 1425 | int slot; |
| 1426 | int ret; |
| 1427 | struct btrfs_root_item *root_item = &root->root_item; |
| 1428 | |
| 1429 | for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { |
| 1430 | slot = path->slots[i]; |
| 1431 | if (slot < btrfs_header_nritems( |
| 1432 | btrfs_buffer_header(path->nodes[i])) - 1) { |
| 1433 | struct btrfs_node *node; |
| 1434 | node = btrfs_buffer_node(path->nodes[i]); |
| 1435 | path->slots[i]++; |
| 1436 | *level = i; |
| 1437 | WARN_ON(*level == 0); |
| 1438 | memcpy(&root_item->drop_progress, |
| 1439 | &node->ptrs[path->slots[i]].key, |
| 1440 | sizeof(root_item->drop_progress)); |
| 1441 | root_item->drop_level = i; |
| 1442 | return 0; |
| 1443 | } else { |
| 1444 | ret = btrfs_free_extent(trans, root, |
| 1445 | bh_blocknr(path->nodes[*level]), |
| 1446 | 1, 1); |
| 1447 | BUG_ON(ret); |
| 1448 | btrfs_block_release(root, path->nodes[*level]); |
| 1449 | path->nodes[*level] = NULL; |
| 1450 | *level = i + 1; |
| 1451 | } |
| 1452 | } |
| 1453 | return 1; |
| 1454 | } |
| 1455 | |
| 1456 | /* |
| 1457 | * drop the reference count on the tree rooted at 'snap'. This traverses |
| 1458 | * the tree freeing any blocks that have a ref count of zero after being |
| 1459 | * decremented. |
| 1460 | */ |
| 1461 | int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root |
| 1462 | *root) |
| 1463 | { |
| 1464 | int ret = 0; |
| 1465 | int wret; |
| 1466 | int level; |
| 1467 | struct btrfs_path *path; |
| 1468 | int i; |
| 1469 | int orig_level; |
| 1470 | struct btrfs_root_item *root_item = &root->root_item; |
| 1471 | |
| 1472 | path = btrfs_alloc_path(); |
| 1473 | BUG_ON(!path); |
| 1474 | |
| 1475 | level = btrfs_header_level(btrfs_buffer_header(root->node)); |
| 1476 | orig_level = level; |
| 1477 | if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { |
| 1478 | path->nodes[level] = root->node; |
| 1479 | path->slots[level] = 0; |
| 1480 | } else { |
| 1481 | struct btrfs_key key; |
| 1482 | struct btrfs_disk_key *found_key; |
| 1483 | struct btrfs_node *node; |
| 1484 | |
| 1485 | btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); |
| 1486 | level = root_item->drop_level; |
| 1487 | path->lowest_level = level; |
| 1488 | wret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 1489 | if (wret < 0) { |
| 1490 | ret = wret; |
| 1491 | goto out; |
| 1492 | } |
| 1493 | node = btrfs_buffer_node(path->nodes[level]); |
| 1494 | found_key = &node->ptrs[path->slots[level]].key; |
| 1495 | WARN_ON(memcmp(found_key, &root_item->drop_progress, |
| 1496 | sizeof(*found_key))); |
| 1497 | } |
| 1498 | while(1) { |
| 1499 | wret = walk_down_tree(trans, root, path, &level); |
| 1500 | if (wret > 0) |
| 1501 | break; |
| 1502 | if (wret < 0) |
| 1503 | ret = wret; |
| 1504 | |
| 1505 | wret = walk_up_tree(trans, root, path, &level); |
| 1506 | if (wret > 0) |
| 1507 | break; |
| 1508 | if (wret < 0) |
| 1509 | ret = wret; |
| 1510 | ret = -EAGAIN; |
| 1511 | get_bh(root->node); |
| 1512 | break; |
| 1513 | } |
| 1514 | for (i = 0; i <= orig_level; i++) { |
| 1515 | if (path->nodes[i]) { |
| 1516 | btrfs_block_release(root, path->nodes[i]); |
| 1517 | path->nodes[i] = 0; |
| 1518 | } |
| 1519 | } |
| 1520 | out: |
| 1521 | btrfs_free_path(path); |
| 1522 | return ret; |
| 1523 | } |
| 1524 | |
| 1525 | static int free_block_group_radix(struct radix_tree_root *radix) |
| 1526 | { |
| 1527 | int ret; |
| 1528 | struct btrfs_block_group_cache *cache[8]; |
| 1529 | int i; |
| 1530 | |
| 1531 | while(1) { |
| 1532 | ret = radix_tree_gang_lookup(radix, (void **)cache, 0, |
| 1533 | ARRAY_SIZE(cache)); |
| 1534 | if (!ret) |
| 1535 | break; |
| 1536 | for (i = 0; i < ret; i++) { |
| 1537 | radix_tree_delete(radix, cache[i]->key.objectid + |
| 1538 | cache[i]->key.offset - 1); |
| 1539 | kfree(cache[i]); |
| 1540 | } |
| 1541 | } |
| 1542 | return 0; |
| 1543 | } |
| 1544 | |
| 1545 | int btrfs_free_block_groups(struct btrfs_fs_info *info) |
| 1546 | { |
| 1547 | int ret; |
| 1548 | int ret2; |
| 1549 | unsigned long gang[16]; |
| 1550 | int i; |
| 1551 | |
| 1552 | ret = free_block_group_radix(&info->block_group_radix); |
| 1553 | ret2 = free_block_group_radix(&info->block_group_data_radix); |
| 1554 | if (ret) |
| 1555 | return ret; |
| 1556 | if (ret2) |
| 1557 | return ret2; |
| 1558 | |
| 1559 | while(1) { |
| 1560 | ret = find_first_radix_bit(&info->extent_map_radix, |
| 1561 | gang, 0, ARRAY_SIZE(gang)); |
| 1562 | if (!ret) |
| 1563 | break; |
| 1564 | for (i = 0; i < ret; i++) { |
| 1565 | clear_radix_bit(&info->extent_map_radix, gang[i]); |
| 1566 | } |
| 1567 | } |
| 1568 | return 0; |
| 1569 | } |
| 1570 | |
| 1571 | int btrfs_read_block_groups(struct btrfs_root *root) |
| 1572 | { |
| 1573 | struct btrfs_path *path; |
| 1574 | int ret; |
| 1575 | int err = 0; |
| 1576 | struct btrfs_block_group_item *bi; |
| 1577 | struct btrfs_block_group_cache *cache; |
| 1578 | struct btrfs_fs_info *info = root->fs_info; |
| 1579 | struct radix_tree_root *radix; |
| 1580 | struct btrfs_key key; |
| 1581 | struct btrfs_key found_key; |
| 1582 | struct btrfs_leaf *leaf; |
| 1583 | u64 group_size_blocks; |
| 1584 | u64 used; |
| 1585 | |
| 1586 | group_size_blocks = BTRFS_BLOCK_GROUP_SIZE >> |
| 1587 | root->fs_info->sb->s_blocksize_bits; |
| 1588 | root = info->extent_root; |
| 1589 | key.objectid = 0; |
| 1590 | key.offset = group_size_blocks; |
| 1591 | key.flags = 0; |
| 1592 | btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY); |
| 1593 | |
| 1594 | path = btrfs_alloc_path(); |
| 1595 | if (!path) |
| 1596 | return -ENOMEM; |
| 1597 | |
| 1598 | while(1) { |
| 1599 | ret = btrfs_search_slot(NULL, info->extent_root, |
| 1600 | &key, path, 0, 0); |
| 1601 | if (ret != 0) { |
| 1602 | err = ret; |
| 1603 | break; |
| 1604 | } |
| 1605 | leaf = btrfs_buffer_leaf(path->nodes[0]); |
| 1606 | btrfs_disk_key_to_cpu(&found_key, |
| 1607 | &leaf->items[path->slots[0]].key); |
| 1608 | cache = kmalloc(sizeof(*cache), GFP_NOFS); |
| 1609 | if (!cache) { |
| 1610 | err = -1; |
| 1611 | break; |
| 1612 | } |
| 1613 | |
| 1614 | bi = btrfs_item_ptr(leaf, path->slots[0], |
| 1615 | struct btrfs_block_group_item); |
| 1616 | if (bi->flags & BTRFS_BLOCK_GROUP_DATA) { |
| 1617 | radix = &info->block_group_data_radix; |
| 1618 | cache->data = 1; |
| 1619 | } else { |
| 1620 | radix = &info->block_group_radix; |
| 1621 | cache->data = 0; |
| 1622 | } |
| 1623 | |
| 1624 | memcpy(&cache->item, bi, sizeof(*bi)); |
| 1625 | memcpy(&cache->key, &found_key, sizeof(found_key)); |
| 1626 | cache->last_alloc = cache->key.objectid; |
| 1627 | cache->first_free = cache->key.objectid; |
| 1628 | cache->pinned = 0; |
| 1629 | cache->cached = 0; |
| 1630 | |
| 1631 | cache->radix = radix; |
| 1632 | |
| 1633 | key.objectid = found_key.objectid + found_key.offset; |
| 1634 | btrfs_release_path(root, path); |
| 1635 | ret = radix_tree_insert(radix, found_key.objectid + |
| 1636 | found_key.offset - 1, |
| 1637 | (void *)cache); |
| 1638 | BUG_ON(ret); |
| 1639 | used = btrfs_block_group_used(bi); |
| 1640 | if (used < div_factor(key.offset, 8)) { |
| 1641 | radix_tree_tag_set(radix, found_key.objectid + |
| 1642 | found_key.offset - 1, |
| 1643 | BTRFS_BLOCK_GROUP_AVAIL); |
| 1644 | } |
| 1645 | if (key.objectid >= |
| 1646 | btrfs_super_total_blocks(&info->super_copy)) |
| 1647 | break; |
| 1648 | } |
| 1649 | |
| 1650 | btrfs_free_path(path); |
| 1651 | return 0; |
| 1652 | } |