Commit | Line | Data |
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c1d7c514 | 1 | // SPDX-License-Identifier: GPL-2.0 |
a5ed9182 OS |
2 | /* |
3 | * Copyright (C) 2015 Facebook. All rights reserved. | |
a5ed9182 OS |
4 | */ |
5 | ||
6 | #include <linux/kernel.h> | |
25ff17e8 | 7 | #include <linux/sched/mm.h> |
9b569ea0 | 8 | #include "messages.h" |
a5ed9182 OS |
9 | #include "ctree.h" |
10 | #include "disk-io.h" | |
11 | #include "locking.h" | |
12 | #include "free-space-tree.h" | |
13 | #include "transaction.h" | |
aac0023c | 14 | #include "block-group.h" |
c7f13d42 | 15 | #include "fs.h" |
07e81dc9 | 16 | #include "accessors.h" |
a0231804 | 17 | #include "extent-tree.h" |
45c40c8f | 18 | #include "root-tree.h" |
a5ed9182 OS |
19 | |
20 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, | |
32da5386 | 21 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
22 | struct btrfs_path *path); |
23 | ||
7939dd9f JB |
24 | static struct btrfs_root *btrfs_free_space_root( |
25 | struct btrfs_block_group *block_group) | |
26 | { | |
abed4aaa JB |
27 | struct btrfs_key key = { |
28 | .objectid = BTRFS_FREE_SPACE_TREE_OBJECTID, | |
29 | .type = BTRFS_ROOT_ITEM_KEY, | |
30 | .offset = 0, | |
31 | }; | |
32 | ||
f7238e50 JB |
33 | if (btrfs_fs_incompat(block_group->fs_info, EXTENT_TREE_V2)) |
34 | key.offset = block_group->global_root_id; | |
abed4aaa | 35 | return btrfs_global_root(block_group->fs_info, &key); |
7939dd9f JB |
36 | } |
37 | ||
32da5386 | 38 | void set_free_space_tree_thresholds(struct btrfs_block_group *cache) |
a5ed9182 OS |
39 | { |
40 | u32 bitmap_range; | |
41 | size_t bitmap_size; | |
42 | u64 num_bitmaps, total_bitmap_size; | |
43 | ||
e3e39c72 MPS |
44 | if (WARN_ON(cache->length == 0)) |
45 | btrfs_warn(cache->fs_info, "block group %llu length is zero", | |
46 | cache->start); | |
47 | ||
a5ed9182 OS |
48 | /* |
49 | * We convert to bitmaps when the disk space required for using extents | |
50 | * exceeds that required for using bitmaps. | |
51 | */ | |
da17066c | 52 | bitmap_range = cache->fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
b3470b5d | 53 | num_bitmaps = div_u64(cache->length + bitmap_range - 1, bitmap_range); |
a5ed9182 OS |
54 | bitmap_size = sizeof(struct btrfs_item) + BTRFS_FREE_SPACE_BITMAP_SIZE; |
55 | total_bitmap_size = num_bitmaps * bitmap_size; | |
56 | cache->bitmap_high_thresh = div_u64(total_bitmap_size, | |
57 | sizeof(struct btrfs_item)); | |
58 | ||
59 | /* | |
60 | * We allow for a small buffer between the high threshold and low | |
61 | * threshold to avoid thrashing back and forth between the two formats. | |
62 | */ | |
63 | if (cache->bitmap_high_thresh > 100) | |
64 | cache->bitmap_low_thresh = cache->bitmap_high_thresh - 100; | |
65 | else | |
66 | cache->bitmap_low_thresh = 0; | |
67 | } | |
68 | ||
69 | static int add_new_free_space_info(struct btrfs_trans_handle *trans, | |
32da5386 | 70 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
71 | struct btrfs_path *path) |
72 | { | |
7939dd9f | 73 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
74 | struct btrfs_free_space_info *info; |
75 | struct btrfs_key key; | |
76 | struct extent_buffer *leaf; | |
77 | int ret; | |
78 | ||
b3470b5d | 79 | key.objectid = block_group->start; |
a5ed9182 | 80 | key.type = BTRFS_FREE_SPACE_INFO_KEY; |
b3470b5d | 81 | key.offset = block_group->length; |
a5ed9182 OS |
82 | |
83 | ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*info)); | |
84 | if (ret) | |
85 | goto out; | |
86 | ||
87 | leaf = path->nodes[0]; | |
88 | info = btrfs_item_ptr(leaf, path->slots[0], | |
89 | struct btrfs_free_space_info); | |
90 | btrfs_set_free_space_extent_count(leaf, info, 0); | |
91 | btrfs_set_free_space_flags(leaf, info, 0); | |
50564b65 | 92 | btrfs_mark_buffer_dirty(trans, leaf); |
a5ed9182 OS |
93 | |
94 | ret = 0; | |
95 | out: | |
96 | btrfs_release_path(path); | |
97 | return ret; | |
98 | } | |
99 | ||
ce9f967f JT |
100 | EXPORT_FOR_TESTS |
101 | struct btrfs_free_space_info *search_free_space_info( | |
2ccf545e | 102 | struct btrfs_trans_handle *trans, |
32da5386 | 103 | struct btrfs_block_group *block_group, |
ce9f967f | 104 | struct btrfs_path *path, int cow) |
a5ed9182 | 105 | { |
2ccf545e | 106 | struct btrfs_fs_info *fs_info = block_group->fs_info; |
7939dd9f | 107 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
108 | struct btrfs_key key; |
109 | int ret; | |
110 | ||
b3470b5d | 111 | key.objectid = block_group->start; |
a5ed9182 | 112 | key.type = BTRFS_FREE_SPACE_INFO_KEY; |
b3470b5d | 113 | key.offset = block_group->length; |
a5ed9182 OS |
114 | |
115 | ret = btrfs_search_slot(trans, root, &key, path, 0, cow); | |
116 | if (ret < 0) | |
117 | return ERR_PTR(ret); | |
118 | if (ret != 0) { | |
ab8d0fc4 | 119 | btrfs_warn(fs_info, "missing free space info for %llu", |
b3470b5d | 120 | block_group->start); |
a5ed9182 OS |
121 | ASSERT(0); |
122 | return ERR_PTR(-ENOENT); | |
123 | } | |
124 | ||
125 | return btrfs_item_ptr(path->nodes[0], path->slots[0], | |
126 | struct btrfs_free_space_info); | |
127 | } | |
128 | ||
129 | /* | |
130 | * btrfs_search_slot() but we're looking for the greatest key less than the | |
131 | * passed key. | |
132 | */ | |
133 | static int btrfs_search_prev_slot(struct btrfs_trans_handle *trans, | |
134 | struct btrfs_root *root, | |
135 | struct btrfs_key *key, struct btrfs_path *p, | |
136 | int ins_len, int cow) | |
137 | { | |
138 | int ret; | |
139 | ||
140 | ret = btrfs_search_slot(trans, root, key, p, ins_len, cow); | |
141 | if (ret < 0) | |
142 | return ret; | |
143 | ||
144 | if (ret == 0) { | |
145 | ASSERT(0); | |
146 | return -EIO; | |
147 | } | |
148 | ||
149 | if (p->slots[0] == 0) { | |
150 | ASSERT(0); | |
151 | return -EIO; | |
152 | } | |
153 | p->slots[0]--; | |
154 | ||
155 | return 0; | |
156 | } | |
157 | ||
098e6308 DS |
158 | static inline u32 free_space_bitmap_size(const struct btrfs_fs_info *fs_info, |
159 | u64 size) | |
a5ed9182 | 160 | { |
098e6308 | 161 | return DIV_ROUND_UP(size >> fs_info->sectorsize_bits, BITS_PER_BYTE); |
a5ed9182 OS |
162 | } |
163 | ||
a565971f | 164 | static unsigned long *alloc_bitmap(u32 bitmap_size) |
a5ed9182 | 165 | { |
a565971f | 166 | unsigned long *ret; |
25ff17e8 | 167 | unsigned int nofs_flag; |
a565971f | 168 | u32 bitmap_rounded_size = round_up(bitmap_size, sizeof(unsigned long)); |
79b134a2 DS |
169 | |
170 | /* | |
25ff17e8 OS |
171 | * GFP_NOFS doesn't work with kvmalloc(), but we really can't recurse |
172 | * into the filesystem as the free space bitmap can be modified in the | |
173 | * critical section of a transaction commit. | |
174 | * | |
175 | * TODO: push the memalloc_nofs_{save,restore}() to the caller where we | |
176 | * know that recursion is unsafe. | |
79b134a2 | 177 | */ |
25ff17e8 | 178 | nofs_flag = memalloc_nofs_save(); |
a565971f | 179 | ret = kvzalloc(bitmap_rounded_size, GFP_KERNEL); |
25ff17e8 OS |
180 | memalloc_nofs_restore(nofs_flag); |
181 | return ret; | |
a5ed9182 OS |
182 | } |
183 | ||
a565971f | 184 | static void le_bitmap_set(unsigned long *map, unsigned int start, int len) |
6faa8f47 | 185 | { |
a565971f | 186 | u8 *p = ((u8 *)map) + BIT_BYTE(start); |
6faa8f47 HM |
187 | const unsigned int size = start + len; |
188 | int bits_to_set = BITS_PER_BYTE - (start % BITS_PER_BYTE); | |
189 | u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(start); | |
190 | ||
191 | while (len - bits_to_set >= 0) { | |
192 | *p |= mask_to_set; | |
193 | len -= bits_to_set; | |
194 | bits_to_set = BITS_PER_BYTE; | |
195 | mask_to_set = ~0; | |
196 | p++; | |
197 | } | |
198 | if (len) { | |
199 | mask_to_set &= BITMAP_LAST_BYTE_MASK(size); | |
200 | *p |= mask_to_set; | |
201 | } | |
202 | } | |
203 | ||
ce9f967f | 204 | EXPORT_FOR_TESTS |
a5ed9182 | 205 | int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, |
32da5386 | 206 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
207 | struct btrfs_path *path) |
208 | { | |
719fb4de | 209 | struct btrfs_fs_info *fs_info = trans->fs_info; |
7939dd9f | 210 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
211 | struct btrfs_free_space_info *info; |
212 | struct btrfs_key key, found_key; | |
213 | struct extent_buffer *leaf; | |
a565971f HM |
214 | unsigned long *bitmap; |
215 | char *bitmap_cursor; | |
a5ed9182 OS |
216 | u64 start, end; |
217 | u64 bitmap_range, i; | |
218 | u32 bitmap_size, flags, expected_extent_count; | |
219 | u32 extent_count = 0; | |
220 | int done = 0, nr; | |
221 | int ret; | |
222 | ||
098e6308 | 223 | bitmap_size = free_space_bitmap_size(fs_info, block_group->length); |
a5ed9182 OS |
224 | bitmap = alloc_bitmap(bitmap_size); |
225 | if (!bitmap) { | |
226 | ret = -ENOMEM; | |
227 | goto out; | |
228 | } | |
229 | ||
b3470b5d DS |
230 | start = block_group->start; |
231 | end = block_group->start + block_group->length; | |
a5ed9182 OS |
232 | |
233 | key.objectid = end - 1; | |
234 | key.type = (u8)-1; | |
235 | key.offset = (u64)-1; | |
236 | ||
237 | while (!done) { | |
238 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
239 | if (ret) | |
240 | goto out; | |
241 | ||
242 | leaf = path->nodes[0]; | |
243 | nr = 0; | |
244 | path->slots[0]++; | |
245 | while (path->slots[0] > 0) { | |
246 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
247 | ||
248 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
b3470b5d DS |
249 | ASSERT(found_key.objectid == block_group->start); |
250 | ASSERT(found_key.offset == block_group->length); | |
a5ed9182 OS |
251 | done = 1; |
252 | break; | |
253 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY) { | |
254 | u64 first, last; | |
255 | ||
256 | ASSERT(found_key.objectid >= start); | |
257 | ASSERT(found_key.objectid < end); | |
258 | ASSERT(found_key.objectid + found_key.offset <= end); | |
259 | ||
260 | first = div_u64(found_key.objectid - start, | |
0b246afa | 261 | fs_info->sectorsize); |
a5ed9182 | 262 | last = div_u64(found_key.objectid + found_key.offset - start, |
0b246afa | 263 | fs_info->sectorsize); |
2fe1d551 | 264 | le_bitmap_set(bitmap, first, last - first); |
a5ed9182 OS |
265 | |
266 | extent_count++; | |
267 | nr++; | |
268 | path->slots[0]--; | |
269 | } else { | |
270 | ASSERT(0); | |
271 | } | |
272 | } | |
273 | ||
274 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
275 | if (ret) | |
276 | goto out; | |
277 | btrfs_release_path(path); | |
278 | } | |
279 | ||
2ccf545e | 280 | info = search_free_space_info(trans, block_group, path, 1); |
a5ed9182 OS |
281 | if (IS_ERR(info)) { |
282 | ret = PTR_ERR(info); | |
283 | goto out; | |
284 | } | |
285 | leaf = path->nodes[0]; | |
286 | flags = btrfs_free_space_flags(leaf, info); | |
287 | flags |= BTRFS_FREE_SPACE_USING_BITMAPS; | |
288 | btrfs_set_free_space_flags(leaf, info, flags); | |
289 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
50564b65 | 290 | btrfs_mark_buffer_dirty(trans, leaf); |
a5ed9182 OS |
291 | btrfs_release_path(path); |
292 | ||
293 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
294 | btrfs_err(fs_info, |
295 | "incorrect extent count for %llu; counted %u, expected %u", | |
b3470b5d | 296 | block_group->start, extent_count, |
a5ed9182 OS |
297 | expected_extent_count); |
298 | ASSERT(0); | |
299 | ret = -EIO; | |
300 | goto out; | |
301 | } | |
302 | ||
a565971f | 303 | bitmap_cursor = (char *)bitmap; |
0b246afa | 304 | bitmap_range = fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
a5ed9182 OS |
305 | i = start; |
306 | while (i < end) { | |
307 | unsigned long ptr; | |
308 | u64 extent_size; | |
309 | u32 data_size; | |
310 | ||
311 | extent_size = min(end - i, bitmap_range); | |
098e6308 | 312 | data_size = free_space_bitmap_size(fs_info, extent_size); |
a5ed9182 OS |
313 | |
314 | key.objectid = i; | |
315 | key.type = BTRFS_FREE_SPACE_BITMAP_KEY; | |
316 | key.offset = extent_size; | |
317 | ||
318 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
319 | data_size); | |
320 | if (ret) | |
321 | goto out; | |
322 | ||
323 | leaf = path->nodes[0]; | |
324 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
325 | write_extent_buffer(leaf, bitmap_cursor, ptr, | |
326 | data_size); | |
50564b65 | 327 | btrfs_mark_buffer_dirty(trans, leaf); |
a5ed9182 OS |
328 | btrfs_release_path(path); |
329 | ||
330 | i += extent_size; | |
331 | bitmap_cursor += data_size; | |
332 | } | |
333 | ||
334 | ret = 0; | |
335 | out: | |
79b134a2 | 336 | kvfree(bitmap); |
a5ed9182 | 337 | if (ret) |
66642832 | 338 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
339 | return ret; |
340 | } | |
341 | ||
ce9f967f | 342 | EXPORT_FOR_TESTS |
a5ed9182 | 343 | int convert_free_space_to_extents(struct btrfs_trans_handle *trans, |
32da5386 | 344 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
345 | struct btrfs_path *path) |
346 | { | |
5296c2bf | 347 | struct btrfs_fs_info *fs_info = trans->fs_info; |
7939dd9f | 348 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
349 | struct btrfs_free_space_info *info; |
350 | struct btrfs_key key, found_key; | |
351 | struct extent_buffer *leaf; | |
a565971f | 352 | unsigned long *bitmap; |
a5ed9182 | 353 | u64 start, end; |
a5ed9182 | 354 | u32 bitmap_size, flags, expected_extent_count; |
a565971f | 355 | unsigned long nrbits, start_bit, end_bit; |
a5ed9182 OS |
356 | u32 extent_count = 0; |
357 | int done = 0, nr; | |
358 | int ret; | |
359 | ||
098e6308 | 360 | bitmap_size = free_space_bitmap_size(fs_info, block_group->length); |
a5ed9182 OS |
361 | bitmap = alloc_bitmap(bitmap_size); |
362 | if (!bitmap) { | |
363 | ret = -ENOMEM; | |
364 | goto out; | |
365 | } | |
366 | ||
b3470b5d DS |
367 | start = block_group->start; |
368 | end = block_group->start + block_group->length; | |
a5ed9182 OS |
369 | |
370 | key.objectid = end - 1; | |
371 | key.type = (u8)-1; | |
372 | key.offset = (u64)-1; | |
373 | ||
374 | while (!done) { | |
375 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
376 | if (ret) | |
377 | goto out; | |
378 | ||
379 | leaf = path->nodes[0]; | |
380 | nr = 0; | |
381 | path->slots[0]++; | |
382 | while (path->slots[0] > 0) { | |
383 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
384 | ||
385 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
b3470b5d DS |
386 | ASSERT(found_key.objectid == block_group->start); |
387 | ASSERT(found_key.offset == block_group->length); | |
a5ed9182 OS |
388 | done = 1; |
389 | break; | |
390 | } else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
391 | unsigned long ptr; | |
a565971f | 392 | char *bitmap_cursor; |
a5ed9182 OS |
393 | u32 bitmap_pos, data_size; |
394 | ||
395 | ASSERT(found_key.objectid >= start); | |
396 | ASSERT(found_key.objectid < end); | |
397 | ASSERT(found_key.objectid + found_key.offset <= end); | |
398 | ||
399 | bitmap_pos = div_u64(found_key.objectid - start, | |
0b246afa | 400 | fs_info->sectorsize * |
a5ed9182 | 401 | BITS_PER_BYTE); |
a565971f | 402 | bitmap_cursor = ((char *)bitmap) + bitmap_pos; |
098e6308 DS |
403 | data_size = free_space_bitmap_size(fs_info, |
404 | found_key.offset); | |
a5ed9182 OS |
405 | |
406 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0] - 1); | |
407 | read_extent_buffer(leaf, bitmap_cursor, ptr, | |
408 | data_size); | |
409 | ||
410 | nr++; | |
411 | path->slots[0]--; | |
412 | } else { | |
413 | ASSERT(0); | |
414 | } | |
415 | } | |
416 | ||
417 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
418 | if (ret) | |
419 | goto out; | |
420 | btrfs_release_path(path); | |
421 | } | |
422 | ||
2ccf545e | 423 | info = search_free_space_info(trans, block_group, path, 1); |
a5ed9182 OS |
424 | if (IS_ERR(info)) { |
425 | ret = PTR_ERR(info); | |
426 | goto out; | |
427 | } | |
428 | leaf = path->nodes[0]; | |
429 | flags = btrfs_free_space_flags(leaf, info); | |
430 | flags &= ~BTRFS_FREE_SPACE_USING_BITMAPS; | |
431 | btrfs_set_free_space_flags(leaf, info, flags); | |
432 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
50564b65 | 433 | btrfs_mark_buffer_dirty(trans, leaf); |
a5ed9182 OS |
434 | btrfs_release_path(path); |
435 | ||
ab108d99 | 436 | nrbits = block_group->length >> block_group->fs_info->sectorsize_bits; |
a565971f HM |
437 | start_bit = find_next_bit_le(bitmap, nrbits, 0); |
438 | ||
439 | while (start_bit < nrbits) { | |
440 | end_bit = find_next_zero_bit_le(bitmap, nrbits, start_bit); | |
441 | ASSERT(start_bit < end_bit); | |
442 | ||
443 | key.objectid = start + start_bit * block_group->fs_info->sectorsize; | |
a5ed9182 | 444 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; |
a565971f | 445 | key.offset = (end_bit - start_bit) * block_group->fs_info->sectorsize; |
a5ed9182 OS |
446 | |
447 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
448 | if (ret) | |
449 | goto out; | |
450 | btrfs_release_path(path); | |
451 | ||
452 | extent_count++; | |
a565971f HM |
453 | |
454 | start_bit = find_next_bit_le(bitmap, nrbits, end_bit); | |
a5ed9182 OS |
455 | } |
456 | ||
457 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
458 | btrfs_err(fs_info, |
459 | "incorrect extent count for %llu; counted %u, expected %u", | |
b3470b5d | 460 | block_group->start, extent_count, |
a5ed9182 OS |
461 | expected_extent_count); |
462 | ASSERT(0); | |
463 | ret = -EIO; | |
464 | goto out; | |
465 | } | |
466 | ||
467 | ret = 0; | |
468 | out: | |
79b134a2 | 469 | kvfree(bitmap); |
a5ed9182 | 470 | if (ret) |
66642832 | 471 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
472 | return ret; |
473 | } | |
474 | ||
475 | static int update_free_space_extent_count(struct btrfs_trans_handle *trans, | |
32da5386 | 476 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
477 | struct btrfs_path *path, |
478 | int new_extents) | |
479 | { | |
480 | struct btrfs_free_space_info *info; | |
481 | u32 flags; | |
482 | u32 extent_count; | |
483 | int ret = 0; | |
484 | ||
485 | if (new_extents == 0) | |
486 | return 0; | |
487 | ||
2ccf545e | 488 | info = search_free_space_info(trans, block_group, path, 1); |
a5ed9182 OS |
489 | if (IS_ERR(info)) { |
490 | ret = PTR_ERR(info); | |
491 | goto out; | |
492 | } | |
493 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
494 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
495 | ||
496 | extent_count += new_extents; | |
497 | btrfs_set_free_space_extent_count(path->nodes[0], info, extent_count); | |
50564b65 | 498 | btrfs_mark_buffer_dirty(trans, path->nodes[0]); |
a5ed9182 OS |
499 | btrfs_release_path(path); |
500 | ||
501 | if (!(flags & BTRFS_FREE_SPACE_USING_BITMAPS) && | |
502 | extent_count > block_group->bitmap_high_thresh) { | |
719fb4de | 503 | ret = convert_free_space_to_bitmaps(trans, block_group, path); |
a5ed9182 OS |
504 | } else if ((flags & BTRFS_FREE_SPACE_USING_BITMAPS) && |
505 | extent_count < block_group->bitmap_low_thresh) { | |
5296c2bf | 506 | ret = convert_free_space_to_extents(trans, block_group, path); |
a5ed9182 OS |
507 | } |
508 | ||
509 | out: | |
510 | return ret; | |
511 | } | |
512 | ||
ce9f967f | 513 | EXPORT_FOR_TESTS |
32da5386 | 514 | int free_space_test_bit(struct btrfs_block_group *block_group, |
a5ed9182 OS |
515 | struct btrfs_path *path, u64 offset) |
516 | { | |
517 | struct extent_buffer *leaf; | |
518 | struct btrfs_key key; | |
519 | u64 found_start, found_end; | |
520 | unsigned long ptr, i; | |
521 | ||
522 | leaf = path->nodes[0]; | |
523 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
524 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
525 | ||
526 | found_start = key.objectid; | |
527 | found_end = key.objectid + key.offset; | |
528 | ASSERT(offset >= found_start && offset < found_end); | |
529 | ||
530 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
da17066c JM |
531 | i = div_u64(offset - found_start, |
532 | block_group->fs_info->sectorsize); | |
a5ed9182 OS |
533 | return !!extent_buffer_test_bit(leaf, ptr, i); |
534 | } | |
535 | ||
50564b65 FM |
536 | static void free_space_set_bits(struct btrfs_trans_handle *trans, |
537 | struct btrfs_block_group *block_group, | |
a5ed9182 OS |
538 | struct btrfs_path *path, u64 *start, u64 *size, |
539 | int bit) | |
540 | { | |
0b246afa | 541 | struct btrfs_fs_info *fs_info = block_group->fs_info; |
a5ed9182 OS |
542 | struct extent_buffer *leaf; |
543 | struct btrfs_key key; | |
544 | u64 end = *start + *size; | |
545 | u64 found_start, found_end; | |
546 | unsigned long ptr, first, last; | |
547 | ||
548 | leaf = path->nodes[0]; | |
549 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
550 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
551 | ||
552 | found_start = key.objectid; | |
553 | found_end = key.objectid + key.offset; | |
554 | ASSERT(*start >= found_start && *start < found_end); | |
555 | ASSERT(end > found_start); | |
556 | ||
557 | if (end > found_end) | |
558 | end = found_end; | |
559 | ||
560 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
ab108d99 DS |
561 | first = (*start - found_start) >> fs_info->sectorsize_bits; |
562 | last = (end - found_start) >> fs_info->sectorsize_bits; | |
a5ed9182 OS |
563 | if (bit) |
564 | extent_buffer_bitmap_set(leaf, ptr, first, last - first); | |
565 | else | |
566 | extent_buffer_bitmap_clear(leaf, ptr, first, last - first); | |
50564b65 | 567 | btrfs_mark_buffer_dirty(trans, leaf); |
a5ed9182 OS |
568 | |
569 | *size -= end - *start; | |
570 | *start = end; | |
571 | } | |
572 | ||
573 | /* | |
574 | * We can't use btrfs_next_item() in modify_free_space_bitmap() because | |
575 | * btrfs_next_leaf() doesn't get the path for writing. We can forgo the fancy | |
576 | * tree walking in btrfs_next_leaf() anyways because we know exactly what we're | |
577 | * looking for. | |
578 | */ | |
579 | static int free_space_next_bitmap(struct btrfs_trans_handle *trans, | |
580 | struct btrfs_root *root, struct btrfs_path *p) | |
581 | { | |
582 | struct btrfs_key key; | |
583 | ||
584 | if (p->slots[0] + 1 < btrfs_header_nritems(p->nodes[0])) { | |
585 | p->slots[0]++; | |
586 | return 0; | |
587 | } | |
588 | ||
589 | btrfs_item_key_to_cpu(p->nodes[0], &key, p->slots[0]); | |
590 | btrfs_release_path(p); | |
591 | ||
592 | key.objectid += key.offset; | |
593 | key.type = (u8)-1; | |
594 | key.offset = (u64)-1; | |
595 | ||
596 | return btrfs_search_prev_slot(trans, root, &key, p, 0, 1); | |
597 | } | |
598 | ||
599 | /* | |
600 | * If remove is 1, then we are removing free space, thus clearing bits in the | |
601 | * bitmap. If remove is 0, then we are adding free space, thus setting bits in | |
602 | * the bitmap. | |
603 | */ | |
604 | static int modify_free_space_bitmap(struct btrfs_trans_handle *trans, | |
32da5386 | 605 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
606 | struct btrfs_path *path, |
607 | u64 start, u64 size, int remove) | |
608 | { | |
7939dd9f | 609 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
610 | struct btrfs_key key; |
611 | u64 end = start + size; | |
612 | u64 cur_start, cur_size; | |
613 | int prev_bit, next_bit; | |
614 | int new_extents; | |
615 | int ret; | |
616 | ||
617 | /* | |
618 | * Read the bit for the block immediately before the extent of space if | |
619 | * that block is within the block group. | |
620 | */ | |
b3470b5d | 621 | if (start > block_group->start) { |
da17066c | 622 | u64 prev_block = start - block_group->fs_info->sectorsize; |
a5ed9182 OS |
623 | |
624 | key.objectid = prev_block; | |
625 | key.type = (u8)-1; | |
626 | key.offset = (u64)-1; | |
627 | ||
628 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
629 | if (ret) | |
630 | goto out; | |
631 | ||
632 | prev_bit = free_space_test_bit(block_group, path, prev_block); | |
633 | ||
634 | /* The previous block may have been in the previous bitmap. */ | |
635 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
636 | if (start >= key.objectid + key.offset) { | |
637 | ret = free_space_next_bitmap(trans, root, path); | |
638 | if (ret) | |
639 | goto out; | |
640 | } | |
641 | } else { | |
642 | key.objectid = start; | |
643 | key.type = (u8)-1; | |
644 | key.offset = (u64)-1; | |
645 | ||
646 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
647 | if (ret) | |
648 | goto out; | |
649 | ||
650 | prev_bit = -1; | |
651 | } | |
652 | ||
653 | /* | |
654 | * Iterate over all of the bitmaps overlapped by the extent of space, | |
655 | * clearing/setting bits as required. | |
656 | */ | |
657 | cur_start = start; | |
658 | cur_size = size; | |
659 | while (1) { | |
50564b65 | 660 | free_space_set_bits(trans, block_group, path, &cur_start, &cur_size, |
a5ed9182 OS |
661 | !remove); |
662 | if (cur_size == 0) | |
663 | break; | |
664 | ret = free_space_next_bitmap(trans, root, path); | |
665 | if (ret) | |
666 | goto out; | |
667 | } | |
668 | ||
669 | /* | |
670 | * Read the bit for the block immediately after the extent of space if | |
671 | * that block is within the block group. | |
672 | */ | |
b3470b5d | 673 | if (end < block_group->start + block_group->length) { |
a5ed9182 OS |
674 | /* The next block may be in the next bitmap. */ |
675 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
676 | if (end >= key.objectid + key.offset) { | |
677 | ret = free_space_next_bitmap(trans, root, path); | |
678 | if (ret) | |
679 | goto out; | |
680 | } | |
681 | ||
682 | next_bit = free_space_test_bit(block_group, path, end); | |
683 | } else { | |
684 | next_bit = -1; | |
685 | } | |
686 | ||
687 | if (remove) { | |
688 | new_extents = -1; | |
689 | if (prev_bit == 1) { | |
690 | /* Leftover on the left. */ | |
691 | new_extents++; | |
692 | } | |
693 | if (next_bit == 1) { | |
694 | /* Leftover on the right. */ | |
695 | new_extents++; | |
696 | } | |
697 | } else { | |
698 | new_extents = 1; | |
699 | if (prev_bit == 1) { | |
700 | /* Merging with neighbor on the left. */ | |
701 | new_extents--; | |
702 | } | |
703 | if (next_bit == 1) { | |
704 | /* Merging with neighbor on the right. */ | |
705 | new_extents--; | |
706 | } | |
707 | } | |
708 | ||
709 | btrfs_release_path(path); | |
690d7682 | 710 | ret = update_free_space_extent_count(trans, block_group, path, |
a5ed9182 OS |
711 | new_extents); |
712 | ||
713 | out: | |
714 | return ret; | |
715 | } | |
716 | ||
717 | static int remove_free_space_extent(struct btrfs_trans_handle *trans, | |
32da5386 | 718 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
719 | struct btrfs_path *path, |
720 | u64 start, u64 size) | |
721 | { | |
7939dd9f | 722 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
723 | struct btrfs_key key; |
724 | u64 found_start, found_end; | |
725 | u64 end = start + size; | |
726 | int new_extents = -1; | |
727 | int ret; | |
728 | ||
729 | key.objectid = start; | |
730 | key.type = (u8)-1; | |
731 | key.offset = (u64)-1; | |
732 | ||
733 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
734 | if (ret) | |
735 | goto out; | |
736 | ||
737 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
738 | ||
739 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
740 | ||
741 | found_start = key.objectid; | |
742 | found_end = key.objectid + key.offset; | |
743 | ASSERT(start >= found_start && end <= found_end); | |
744 | ||
745 | /* | |
746 | * Okay, now that we've found the free space extent which contains the | |
747 | * free space that we are removing, there are four cases: | |
748 | * | |
749 | * 1. We're using the whole extent: delete the key we found and | |
750 | * decrement the free space extent count. | |
751 | * 2. We are using part of the extent starting at the beginning: delete | |
752 | * the key we found and insert a new key representing the leftover at | |
753 | * the end. There is no net change in the number of extents. | |
754 | * 3. We are using part of the extent ending at the end: delete the key | |
755 | * we found and insert a new key representing the leftover at the | |
756 | * beginning. There is no net change in the number of extents. | |
757 | * 4. We are using part of the extent in the middle: delete the key we | |
758 | * found and insert two new keys representing the leftovers on each | |
759 | * side. Where we used to have one extent, we now have two, so increment | |
760 | * the extent count. We may need to convert the block group to bitmaps | |
761 | * as a result. | |
762 | */ | |
763 | ||
764 | /* Delete the existing key (cases 1-4). */ | |
765 | ret = btrfs_del_item(trans, root, path); | |
766 | if (ret) | |
767 | goto out; | |
768 | ||
769 | /* Add a key for leftovers at the beginning (cases 3 and 4). */ | |
770 | if (start > found_start) { | |
771 | key.objectid = found_start; | |
772 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
773 | key.offset = start - found_start; | |
774 | ||
775 | btrfs_release_path(path); | |
776 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
777 | if (ret) | |
778 | goto out; | |
779 | new_extents++; | |
780 | } | |
781 | ||
782 | /* Add a key for leftovers at the end (cases 2 and 4). */ | |
783 | if (end < found_end) { | |
784 | key.objectid = end; | |
785 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
786 | key.offset = found_end - end; | |
787 | ||
788 | btrfs_release_path(path); | |
789 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
790 | if (ret) | |
791 | goto out; | |
792 | new_extents++; | |
793 | } | |
794 | ||
795 | btrfs_release_path(path); | |
690d7682 | 796 | ret = update_free_space_extent_count(trans, block_group, path, |
a5ed9182 OS |
797 | new_extents); |
798 | ||
799 | out: | |
800 | return ret; | |
801 | } | |
802 | ||
ce9f967f | 803 | EXPORT_FOR_TESTS |
a5ed9182 | 804 | int __remove_from_free_space_tree(struct btrfs_trans_handle *trans, |
32da5386 | 805 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
806 | struct btrfs_path *path, u64 start, u64 size) |
807 | { | |
808 | struct btrfs_free_space_info *info; | |
809 | u32 flags; | |
810 | int ret; | |
811 | ||
0d7764ff | 812 | if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) { |
9a7e0f92 | 813 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
814 | if (ret) |
815 | return ret; | |
816 | } | |
817 | ||
2ccf545e | 818 | info = search_free_space_info(NULL, block_group, path, 0); |
a5ed9182 OS |
819 | if (IS_ERR(info)) |
820 | return PTR_ERR(info); | |
821 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
822 | btrfs_release_path(path); | |
823 | ||
824 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
85a7ef13 NB |
825 | return modify_free_space_bitmap(trans, block_group, path, |
826 | start, size, 1); | |
a5ed9182 | 827 | } else { |
e581168d NB |
828 | return remove_free_space_extent(trans, block_group, path, |
829 | start, size); | |
a5ed9182 OS |
830 | } |
831 | } | |
832 | ||
833 | int remove_from_free_space_tree(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
834 | u64 start, u64 size) |
835 | { | |
32da5386 | 836 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
837 | struct btrfs_path *path; |
838 | int ret; | |
839 | ||
25a356d3 | 840 | if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE)) |
a5ed9182 OS |
841 | return 0; |
842 | ||
843 | path = btrfs_alloc_path(); | |
844 | if (!path) { | |
845 | ret = -ENOMEM; | |
846 | goto out; | |
847 | } | |
848 | ||
25a356d3 | 849 | block_group = btrfs_lookup_block_group(trans->fs_info, start); |
a5ed9182 OS |
850 | if (!block_group) { |
851 | ASSERT(0); | |
852 | ret = -ENOENT; | |
853 | goto out; | |
854 | } | |
855 | ||
856 | mutex_lock(&block_group->free_space_lock); | |
c31683a6 NB |
857 | ret = __remove_from_free_space_tree(trans, block_group, path, start, |
858 | size); | |
a5ed9182 OS |
859 | mutex_unlock(&block_group->free_space_lock); |
860 | ||
861 | btrfs_put_block_group(block_group); | |
862 | out: | |
863 | btrfs_free_path(path); | |
864 | if (ret) | |
66642832 | 865 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
866 | return ret; |
867 | } | |
868 | ||
869 | static int add_free_space_extent(struct btrfs_trans_handle *trans, | |
32da5386 | 870 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
871 | struct btrfs_path *path, |
872 | u64 start, u64 size) | |
873 | { | |
7939dd9f | 874 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
875 | struct btrfs_key key, new_key; |
876 | u64 found_start, found_end; | |
877 | u64 end = start + size; | |
878 | int new_extents = 1; | |
879 | int ret; | |
880 | ||
881 | /* | |
882 | * We are adding a new extent of free space, but we need to merge | |
883 | * extents. There are four cases here: | |
884 | * | |
885 | * 1. The new extent does not have any immediate neighbors to merge | |
886 | * with: add the new key and increment the free space extent count. We | |
887 | * may need to convert the block group to bitmaps as a result. | |
888 | * 2. The new extent has an immediate neighbor before it: remove the | |
889 | * previous key and insert a new key combining both of them. There is no | |
890 | * net change in the number of extents. | |
891 | * 3. The new extent has an immediate neighbor after it: remove the next | |
892 | * key and insert a new key combining both of them. There is no net | |
893 | * change in the number of extents. | |
894 | * 4. The new extent has immediate neighbors on both sides: remove both | |
895 | * of the keys and insert a new key combining all of them. Where we used | |
896 | * to have two extents, we now have one, so decrement the extent count. | |
897 | */ | |
898 | ||
899 | new_key.objectid = start; | |
900 | new_key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
901 | new_key.offset = size; | |
902 | ||
903 | /* Search for a neighbor on the left. */ | |
b3470b5d | 904 | if (start == block_group->start) |
a5ed9182 OS |
905 | goto right; |
906 | key.objectid = start - 1; | |
907 | key.type = (u8)-1; | |
908 | key.offset = (u64)-1; | |
909 | ||
910 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
911 | if (ret) | |
912 | goto out; | |
913 | ||
914 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
915 | ||
916 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
917 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
918 | btrfs_release_path(path); | |
919 | goto right; | |
920 | } | |
921 | ||
922 | found_start = key.objectid; | |
923 | found_end = key.objectid + key.offset; | |
b3470b5d DS |
924 | ASSERT(found_start >= block_group->start && |
925 | found_end > block_group->start); | |
a5ed9182 OS |
926 | ASSERT(found_start < start && found_end <= start); |
927 | ||
928 | /* | |
929 | * Delete the neighbor on the left and absorb it into the new key (cases | |
930 | * 2 and 4). | |
931 | */ | |
932 | if (found_end == start) { | |
933 | ret = btrfs_del_item(trans, root, path); | |
934 | if (ret) | |
935 | goto out; | |
936 | new_key.objectid = found_start; | |
937 | new_key.offset += key.offset; | |
938 | new_extents--; | |
939 | } | |
940 | btrfs_release_path(path); | |
941 | ||
942 | right: | |
943 | /* Search for a neighbor on the right. */ | |
b3470b5d | 944 | if (end == block_group->start + block_group->length) |
a5ed9182 OS |
945 | goto insert; |
946 | key.objectid = end; | |
947 | key.type = (u8)-1; | |
948 | key.offset = (u64)-1; | |
949 | ||
950 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
951 | if (ret) | |
952 | goto out; | |
953 | ||
954 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
955 | ||
956 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
957 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
958 | btrfs_release_path(path); | |
959 | goto insert; | |
960 | } | |
961 | ||
962 | found_start = key.objectid; | |
963 | found_end = key.objectid + key.offset; | |
b3470b5d DS |
964 | ASSERT(found_start >= block_group->start && |
965 | found_end > block_group->start); | |
a5ed9182 OS |
966 | ASSERT((found_start < start && found_end <= start) || |
967 | (found_start >= end && found_end > end)); | |
968 | ||
969 | /* | |
970 | * Delete the neighbor on the right and absorb it into the new key | |
971 | * (cases 3 and 4). | |
972 | */ | |
973 | if (found_start == end) { | |
974 | ret = btrfs_del_item(trans, root, path); | |
975 | if (ret) | |
976 | goto out; | |
977 | new_key.offset += key.offset; | |
978 | new_extents--; | |
979 | } | |
980 | btrfs_release_path(path); | |
981 | ||
982 | insert: | |
983 | /* Insert the new key (cases 1-4). */ | |
984 | ret = btrfs_insert_empty_item(trans, root, path, &new_key, 0); | |
985 | if (ret) | |
986 | goto out; | |
987 | ||
988 | btrfs_release_path(path); | |
690d7682 | 989 | ret = update_free_space_extent_count(trans, block_group, path, |
a5ed9182 OS |
990 | new_extents); |
991 | ||
992 | out: | |
993 | return ret; | |
994 | } | |
995 | ||
ce9f967f | 996 | EXPORT_FOR_TESTS |
a5ed9182 | 997 | int __add_to_free_space_tree(struct btrfs_trans_handle *trans, |
32da5386 | 998 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
999 | struct btrfs_path *path, u64 start, u64 size) |
1000 | { | |
1001 | struct btrfs_free_space_info *info; | |
1002 | u32 flags; | |
1003 | int ret; | |
1004 | ||
0d7764ff | 1005 | if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) { |
9a7e0f92 | 1006 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
1007 | if (ret) |
1008 | return ret; | |
1009 | } | |
1010 | ||
2ccf545e | 1011 | info = search_free_space_info(NULL, block_group, path, 0); |
a5ed9182 OS |
1012 | if (IS_ERR(info)) |
1013 | return PTR_ERR(info); | |
1014 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
1015 | btrfs_release_path(path); | |
1016 | ||
1017 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
85a7ef13 NB |
1018 | return modify_free_space_bitmap(trans, block_group, path, |
1019 | start, size, 0); | |
a5ed9182 | 1020 | } else { |
5cb17822 NB |
1021 | return add_free_space_extent(trans, block_group, path, start, |
1022 | size); | |
a5ed9182 OS |
1023 | } |
1024 | } | |
1025 | ||
1026 | int add_to_free_space_tree(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
1027 | u64 start, u64 size) |
1028 | { | |
32da5386 | 1029 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
1030 | struct btrfs_path *path; |
1031 | int ret; | |
1032 | ||
e7355e50 | 1033 | if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE)) |
a5ed9182 OS |
1034 | return 0; |
1035 | ||
1036 | path = btrfs_alloc_path(); | |
1037 | if (!path) { | |
1038 | ret = -ENOMEM; | |
1039 | goto out; | |
1040 | } | |
1041 | ||
e7355e50 | 1042 | block_group = btrfs_lookup_block_group(trans->fs_info, start); |
a5ed9182 OS |
1043 | if (!block_group) { |
1044 | ASSERT(0); | |
1045 | ret = -ENOENT; | |
1046 | goto out; | |
1047 | } | |
1048 | ||
1049 | mutex_lock(&block_group->free_space_lock); | |
2d5cffa1 | 1050 | ret = __add_to_free_space_tree(trans, block_group, path, start, size); |
a5ed9182 OS |
1051 | mutex_unlock(&block_group->free_space_lock); |
1052 | ||
1053 | btrfs_put_block_group(block_group); | |
1054 | out: | |
1055 | btrfs_free_path(path); | |
1056 | if (ret) | |
66642832 | 1057 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1058 | return ret; |
1059 | } | |
1060 | ||
1061 | /* | |
1062 | * Populate the free space tree by walking the extent tree. Operations on the | |
1063 | * extent tree that happen as a result of writes to the free space tree will go | |
1064 | * through the normal add/remove hooks. | |
1065 | */ | |
1066 | static int populate_free_space_tree(struct btrfs_trans_handle *trans, | |
32da5386 | 1067 | struct btrfs_block_group *block_group) |
a5ed9182 | 1068 | { |
29cbcf40 | 1069 | struct btrfs_root *extent_root; |
a5ed9182 OS |
1070 | struct btrfs_path *path, *path2; |
1071 | struct btrfs_key key; | |
1072 | u64 start, end; | |
1073 | int ret; | |
1074 | ||
1075 | path = btrfs_alloc_path(); | |
1076 | if (!path) | |
1077 | return -ENOMEM; | |
019599ad | 1078 | path->reada = READA_FORWARD; |
a5ed9182 OS |
1079 | |
1080 | path2 = btrfs_alloc_path(); | |
1081 | if (!path2) { | |
1082 | btrfs_free_path(path); | |
1083 | return -ENOMEM; | |
1084 | } | |
1085 | ||
66afee18 | 1086 | ret = add_new_free_space_info(trans, block_group, path2); |
a5ed9182 OS |
1087 | if (ret) |
1088 | goto out; | |
1089 | ||
511711af CM |
1090 | mutex_lock(&block_group->free_space_lock); |
1091 | ||
a5ed9182 OS |
1092 | /* |
1093 | * Iterate through all of the extent and metadata items in this block | |
1094 | * group, adding the free space between them and the free space at the | |
1095 | * end. Note that EXTENT_ITEM and METADATA_ITEM are less than | |
1096 | * BLOCK_GROUP_ITEM, so an extent may precede the block group that it's | |
1097 | * contained in. | |
1098 | */ | |
b3470b5d | 1099 | key.objectid = block_group->start; |
a5ed9182 OS |
1100 | key.type = BTRFS_EXTENT_ITEM_KEY; |
1101 | key.offset = 0; | |
1102 | ||
29cbcf40 | 1103 | extent_root = btrfs_extent_root(trans->fs_info, key.objectid); |
a5ed9182 OS |
1104 | ret = btrfs_search_slot_for_read(extent_root, &key, path, 1, 0); |
1105 | if (ret < 0) | |
511711af | 1106 | goto out_locked; |
a5ed9182 OS |
1107 | ASSERT(ret == 0); |
1108 | ||
b3470b5d DS |
1109 | start = block_group->start; |
1110 | end = block_group->start + block_group->length; | |
a5ed9182 OS |
1111 | while (1) { |
1112 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1113 | ||
1114 | if (key.type == BTRFS_EXTENT_ITEM_KEY || | |
1115 | key.type == BTRFS_METADATA_ITEM_KEY) { | |
1116 | if (key.objectid >= end) | |
1117 | break; | |
1118 | ||
1119 | if (start < key.objectid) { | |
2d5cffa1 | 1120 | ret = __add_to_free_space_tree(trans, |
a5ed9182 OS |
1121 | block_group, |
1122 | path2, start, | |
1123 | key.objectid - | |
1124 | start); | |
1125 | if (ret) | |
511711af | 1126 | goto out_locked; |
a5ed9182 OS |
1127 | } |
1128 | start = key.objectid; | |
1129 | if (key.type == BTRFS_METADATA_ITEM_KEY) | |
ffa9a9ef | 1130 | start += trans->fs_info->nodesize; |
a5ed9182 OS |
1131 | else |
1132 | start += key.offset; | |
1133 | } else if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) { | |
b3470b5d | 1134 | if (key.objectid != block_group->start) |
a5ed9182 OS |
1135 | break; |
1136 | } | |
1137 | ||
1138 | ret = btrfs_next_item(extent_root, path); | |
1139 | if (ret < 0) | |
511711af | 1140 | goto out_locked; |
a5ed9182 OS |
1141 | if (ret) |
1142 | break; | |
1143 | } | |
1144 | if (start < end) { | |
2d5cffa1 NB |
1145 | ret = __add_to_free_space_tree(trans, block_group, path2, |
1146 | start, end - start); | |
a5ed9182 | 1147 | if (ret) |
511711af | 1148 | goto out_locked; |
a5ed9182 OS |
1149 | } |
1150 | ||
1151 | ret = 0; | |
511711af CM |
1152 | out_locked: |
1153 | mutex_unlock(&block_group->free_space_lock); | |
a5ed9182 OS |
1154 | out: |
1155 | btrfs_free_path(path2); | |
1156 | btrfs_free_path(path); | |
1157 | return ret; | |
1158 | } | |
1159 | ||
1160 | int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) | |
1161 | { | |
1162 | struct btrfs_trans_handle *trans; | |
1163 | struct btrfs_root *tree_root = fs_info->tree_root; | |
1164 | struct btrfs_root *free_space_root; | |
32da5386 | 1165 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
1166 | struct rb_node *node; |
1167 | int ret; | |
1168 | ||
1169 | trans = btrfs_start_transaction(tree_root, 0); | |
1170 | if (IS_ERR(trans)) | |
1171 | return PTR_ERR(trans); | |
1172 | ||
afcdd129 | 1173 | set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
2f96e402 | 1174 | set_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags); |
9b7a2440 | 1175 | free_space_root = btrfs_create_tree(trans, |
a5ed9182 OS |
1176 | BTRFS_FREE_SPACE_TREE_OBJECTID); |
1177 | if (IS_ERR(free_space_root)) { | |
1178 | ret = PTR_ERR(free_space_root); | |
1179 | goto abort; | |
1180 | } | |
abed4aaa JB |
1181 | ret = btrfs_global_root_insert(free_space_root); |
1182 | if (ret) { | |
1183 | btrfs_put_root(free_space_root); | |
1184 | goto abort; | |
1185 | } | |
a5ed9182 | 1186 | |
08dddb29 | 1187 | node = rb_first_cached(&fs_info->block_group_cache_tree); |
a5ed9182 | 1188 | while (node) { |
32da5386 | 1189 | block_group = rb_entry(node, struct btrfs_block_group, |
a5ed9182 | 1190 | cache_node); |
ffa9a9ef | 1191 | ret = populate_free_space_tree(trans, block_group); |
a5ed9182 OS |
1192 | if (ret) |
1193 | goto abort; | |
1194 | node = rb_next(node); | |
1195 | } | |
1196 | ||
1197 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1198 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
afcdd129 | 1199 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
2f96e402 | 1200 | ret = btrfs_commit_transaction(trans); |
a5ed9182 | 1201 | |
2f96e402 JB |
1202 | /* |
1203 | * Now that we've committed the transaction any reading of our commit | |
1204 | * root will be safe, so we can cache from the free space tree now. | |
1205 | */ | |
1206 | clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags); | |
1207 | return ret; | |
a5ed9182 OS |
1208 | |
1209 | abort: | |
afcdd129 | 1210 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
2f96e402 | 1211 | clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags); |
66642832 | 1212 | btrfs_abort_transaction(trans, ret); |
3a45bb20 | 1213 | btrfs_end_transaction(trans); |
a5ed9182 OS |
1214 | return ret; |
1215 | } | |
1216 | ||
1217 | static int clear_free_space_tree(struct btrfs_trans_handle *trans, | |
1218 | struct btrfs_root *root) | |
1219 | { | |
1220 | struct btrfs_path *path; | |
1221 | struct btrfs_key key; | |
1222 | int nr; | |
1223 | int ret; | |
1224 | ||
1225 | path = btrfs_alloc_path(); | |
1226 | if (!path) | |
1227 | return -ENOMEM; | |
1228 | ||
a5ed9182 OS |
1229 | key.objectid = 0; |
1230 | key.type = 0; | |
1231 | key.offset = 0; | |
1232 | ||
1233 | while (1) { | |
1234 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
1235 | if (ret < 0) | |
1236 | goto out; | |
1237 | ||
1238 | nr = btrfs_header_nritems(path->nodes[0]); | |
1239 | if (!nr) | |
1240 | break; | |
1241 | ||
1242 | path->slots[0] = 0; | |
1243 | ret = btrfs_del_items(trans, root, path, 0, nr); | |
1244 | if (ret) | |
1245 | goto out; | |
1246 | ||
1247 | btrfs_release_path(path); | |
1248 | } | |
1249 | ||
1250 | ret = 0; | |
1251 | out: | |
1252 | btrfs_free_path(path); | |
1253 | return ret; | |
1254 | } | |
1255 | ||
1d6a4fc8 | 1256 | int btrfs_delete_free_space_tree(struct btrfs_fs_info *fs_info) |
a5ed9182 OS |
1257 | { |
1258 | struct btrfs_trans_handle *trans; | |
1259 | struct btrfs_root *tree_root = fs_info->tree_root; | |
abed4aaa JB |
1260 | struct btrfs_key key = { |
1261 | .objectid = BTRFS_FREE_SPACE_TREE_OBJECTID, | |
1262 | .type = BTRFS_ROOT_ITEM_KEY, | |
1263 | .offset = 0, | |
1264 | }; | |
1265 | struct btrfs_root *free_space_root = btrfs_global_root(fs_info, &key); | |
a5ed9182 OS |
1266 | int ret; |
1267 | ||
1268 | trans = btrfs_start_transaction(tree_root, 0); | |
1269 | if (IS_ERR(trans)) | |
1270 | return PTR_ERR(trans); | |
1271 | ||
1272 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1273 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
a5ed9182 OS |
1274 | |
1275 | ret = clear_free_space_tree(trans, free_space_root); | |
0896ce75 DS |
1276 | if (ret) { |
1277 | btrfs_abort_transaction(trans, ret); | |
1278 | btrfs_end_transaction(trans); | |
1279 | return ret; | |
1280 | } | |
a5ed9182 | 1281 | |
ab9ce7d4 | 1282 | ret = btrfs_del_root(trans, &free_space_root->root_key); |
0896ce75 DS |
1283 | if (ret) { |
1284 | btrfs_abort_transaction(trans, ret); | |
1285 | btrfs_end_transaction(trans); | |
1286 | return ret; | |
1287 | } | |
a5ed9182 | 1288 | |
abed4aaa | 1289 | btrfs_global_root_delete(free_space_root); |
babebf02 FM |
1290 | |
1291 | spin_lock(&fs_info->trans_lock); | |
a5ed9182 | 1292 | list_del(&free_space_root->dirty_list); |
babebf02 | 1293 | spin_unlock(&fs_info->trans_lock); |
a5ed9182 OS |
1294 | |
1295 | btrfs_tree_lock(free_space_root->node); | |
190a8339 | 1296 | btrfs_clear_buffer_dirty(trans, free_space_root->node); |
a5ed9182 | 1297 | btrfs_tree_unlock(free_space_root->node); |
7a163608 FM |
1298 | btrfs_free_tree_block(trans, btrfs_root_id(free_space_root), |
1299 | free_space_root->node, 0, 1); | |
a5ed9182 | 1300 | |
00246528 | 1301 | btrfs_put_root(free_space_root); |
a5ed9182 | 1302 | |
0bef7109 | 1303 | return btrfs_commit_transaction(trans); |
a5ed9182 OS |
1304 | } |
1305 | ||
1d6a4fc8 QW |
1306 | int btrfs_rebuild_free_space_tree(struct btrfs_fs_info *fs_info) |
1307 | { | |
1308 | struct btrfs_trans_handle *trans; | |
1309 | struct btrfs_key key = { | |
1310 | .objectid = BTRFS_FREE_SPACE_TREE_OBJECTID, | |
1311 | .type = BTRFS_ROOT_ITEM_KEY, | |
1312 | .offset = 0, | |
1313 | }; | |
1314 | struct btrfs_root *free_space_root = btrfs_global_root(fs_info, &key); | |
1315 | struct rb_node *node; | |
1316 | int ret; | |
1317 | ||
1318 | trans = btrfs_start_transaction(free_space_root, 1); | |
1319 | if (IS_ERR(trans)) | |
1320 | return PTR_ERR(trans); | |
1321 | ||
1322 | set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); | |
1323 | set_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags); | |
1324 | ||
1325 | ret = clear_free_space_tree(trans, free_space_root); | |
1326 | if (ret) | |
1327 | goto abort; | |
1328 | ||
1329 | node = rb_first_cached(&fs_info->block_group_cache_tree); | |
1330 | while (node) { | |
1331 | struct btrfs_block_group *block_group; | |
1332 | ||
1333 | block_group = rb_entry(node, struct btrfs_block_group, | |
1334 | cache_node); | |
1335 | ret = populate_free_space_tree(trans, block_group); | |
1336 | if (ret) | |
1337 | goto abort; | |
1338 | node = rb_next(node); | |
1339 | } | |
1340 | ||
1341 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
1342 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); | |
1343 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); | |
1344 | ||
1345 | ret = btrfs_commit_transaction(trans); | |
1346 | clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags); | |
1347 | return ret; | |
1348 | abort: | |
1349 | btrfs_abort_transaction(trans, ret); | |
1350 | btrfs_end_transaction(trans); | |
1351 | return ret; | |
1352 | } | |
1353 | ||
a5ed9182 | 1354 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, |
32da5386 | 1355 | struct btrfs_block_group *block_group, |
a5ed9182 OS |
1356 | struct btrfs_path *path) |
1357 | { | |
a5ed9182 OS |
1358 | int ret; |
1359 | ||
0d7764ff | 1360 | clear_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags); |
a5ed9182 | 1361 | |
66afee18 | 1362 | ret = add_new_free_space_info(trans, block_group, path); |
a5ed9182 OS |
1363 | if (ret) |
1364 | return ret; | |
1365 | ||
2d5cffa1 | 1366 | return __add_to_free_space_tree(trans, block_group, path, |
b3470b5d DS |
1367 | block_group->start, |
1368 | block_group->length); | |
a5ed9182 OS |
1369 | } |
1370 | ||
1371 | int add_block_group_free_space(struct btrfs_trans_handle *trans, | |
32da5386 | 1372 | struct btrfs_block_group *block_group) |
a5ed9182 | 1373 | { |
e4e0711c | 1374 | struct btrfs_fs_info *fs_info = trans->fs_info; |
a5ed9182 OS |
1375 | struct btrfs_path *path = NULL; |
1376 | int ret = 0; | |
1377 | ||
1378 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1379 | return 0; | |
1380 | ||
1381 | mutex_lock(&block_group->free_space_lock); | |
0d7764ff | 1382 | if (!test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) |
a5ed9182 OS |
1383 | goto out; |
1384 | ||
1385 | path = btrfs_alloc_path(); | |
1386 | if (!path) { | |
1387 | ret = -ENOMEM; | |
1388 | goto out; | |
1389 | } | |
1390 | ||
9a7e0f92 | 1391 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
1392 | |
1393 | out: | |
1394 | btrfs_free_path(path); | |
1395 | mutex_unlock(&block_group->free_space_lock); | |
1396 | if (ret) | |
66642832 | 1397 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1398 | return ret; |
1399 | } | |
1400 | ||
1401 | int remove_block_group_free_space(struct btrfs_trans_handle *trans, | |
32da5386 | 1402 | struct btrfs_block_group *block_group) |
a5ed9182 | 1403 | { |
7939dd9f | 1404 | struct btrfs_root *root = btrfs_free_space_root(block_group); |
a5ed9182 OS |
1405 | struct btrfs_path *path; |
1406 | struct btrfs_key key, found_key; | |
1407 | struct extent_buffer *leaf; | |
1408 | u64 start, end; | |
1409 | int done = 0, nr; | |
1410 | int ret; | |
1411 | ||
f3f72779 | 1412 | if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE)) |
a5ed9182 OS |
1413 | return 0; |
1414 | ||
0d7764ff | 1415 | if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) { |
a5ed9182 OS |
1416 | /* We never added this block group to the free space tree. */ |
1417 | return 0; | |
1418 | } | |
1419 | ||
1420 | path = btrfs_alloc_path(); | |
1421 | if (!path) { | |
1422 | ret = -ENOMEM; | |
1423 | goto out; | |
1424 | } | |
1425 | ||
b3470b5d DS |
1426 | start = block_group->start; |
1427 | end = block_group->start + block_group->length; | |
a5ed9182 OS |
1428 | |
1429 | key.objectid = end - 1; | |
1430 | key.type = (u8)-1; | |
1431 | key.offset = (u64)-1; | |
1432 | ||
1433 | while (!done) { | |
1434 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
1435 | if (ret) | |
1436 | goto out; | |
1437 | ||
1438 | leaf = path->nodes[0]; | |
1439 | nr = 0; | |
1440 | path->slots[0]++; | |
1441 | while (path->slots[0] > 0) { | |
1442 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
1443 | ||
1444 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
b3470b5d DS |
1445 | ASSERT(found_key.objectid == block_group->start); |
1446 | ASSERT(found_key.offset == block_group->length); | |
a5ed9182 OS |
1447 | done = 1; |
1448 | nr++; | |
1449 | path->slots[0]--; | |
1450 | break; | |
1451 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY || | |
1452 | found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
1453 | ASSERT(found_key.objectid >= start); | |
1454 | ASSERT(found_key.objectid < end); | |
1455 | ASSERT(found_key.objectid + found_key.offset <= end); | |
1456 | nr++; | |
1457 | path->slots[0]--; | |
1458 | } else { | |
1459 | ASSERT(0); | |
1460 | } | |
1461 | } | |
1462 | ||
1463 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
1464 | if (ret) | |
1465 | goto out; | |
1466 | btrfs_release_path(path); | |
1467 | } | |
1468 | ||
1469 | ret = 0; | |
1470 | out: | |
1471 | btrfs_free_path(path); | |
1472 | if (ret) | |
66642832 | 1473 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1474 | return ret; |
1475 | } | |
1476 | ||
1477 | static int load_free_space_bitmaps(struct btrfs_caching_control *caching_ctl, | |
1478 | struct btrfs_path *path, | |
1479 | u32 expected_extent_count) | |
1480 | { | |
32da5386 | 1481 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
1482 | struct btrfs_fs_info *fs_info; |
1483 | struct btrfs_root *root; | |
1484 | struct btrfs_key key; | |
1485 | int prev_bit = 0, bit; | |
1486 | /* Initialize to silence GCC. */ | |
1487 | u64 extent_start = 0; | |
1488 | u64 end, offset; | |
1489 | u64 total_found = 0; | |
1490 | u32 extent_count = 0; | |
1491 | int ret; | |
1492 | ||
1493 | block_group = caching_ctl->block_group; | |
1494 | fs_info = block_group->fs_info; | |
7939dd9f | 1495 | root = btrfs_free_space_root(block_group); |
a5ed9182 | 1496 | |
b3470b5d | 1497 | end = block_group->start + block_group->length; |
a5ed9182 OS |
1498 | |
1499 | while (1) { | |
1500 | ret = btrfs_next_item(root, path); | |
1501 | if (ret < 0) | |
1502 | goto out; | |
1503 | if (ret) | |
1504 | break; | |
1505 | ||
1506 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1507 | ||
1508 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1509 | break; | |
1510 | ||
1511 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
1512 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1513 | ||
a5ed9182 OS |
1514 | offset = key.objectid; |
1515 | while (offset < key.objectid + key.offset) { | |
1516 | bit = free_space_test_bit(block_group, path, offset); | |
1517 | if (prev_bit == 0 && bit == 1) { | |
1518 | extent_start = offset; | |
1519 | } else if (prev_bit == 1 && bit == 0) { | |
d8ccbd21 FM |
1520 | u64 space_added; |
1521 | ||
3b9f0995 FM |
1522 | ret = btrfs_add_new_free_space(block_group, |
1523 | extent_start, | |
1524 | offset, | |
1525 | &space_added); | |
d8ccbd21 FM |
1526 | if (ret) |
1527 | goto out; | |
1528 | total_found += space_added; | |
a5ed9182 OS |
1529 | if (total_found > CACHING_CTL_WAKE_UP) { |
1530 | total_found = 0; | |
1531 | wake_up(&caching_ctl->wait); | |
1532 | } | |
1533 | extent_count++; | |
1534 | } | |
1535 | prev_bit = bit; | |
0b246afa | 1536 | offset += fs_info->sectorsize; |
a5ed9182 OS |
1537 | } |
1538 | } | |
1539 | if (prev_bit == 1) { | |
3b9f0995 | 1540 | ret = btrfs_add_new_free_space(block_group, extent_start, end, NULL); |
d8ccbd21 FM |
1541 | if (ret) |
1542 | goto out; | |
a5ed9182 OS |
1543 | extent_count++; |
1544 | } | |
1545 | ||
1546 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1547 | btrfs_err(fs_info, |
1548 | "incorrect extent count for %llu; counted %u, expected %u", | |
b3470b5d | 1549 | block_group->start, extent_count, |
a5ed9182 OS |
1550 | expected_extent_count); |
1551 | ASSERT(0); | |
1552 | ret = -EIO; | |
1553 | goto out; | |
1554 | } | |
1555 | ||
a5ed9182 OS |
1556 | ret = 0; |
1557 | out: | |
1558 | return ret; | |
1559 | } | |
1560 | ||
1561 | static int load_free_space_extents(struct btrfs_caching_control *caching_ctl, | |
1562 | struct btrfs_path *path, | |
1563 | u32 expected_extent_count) | |
1564 | { | |
32da5386 | 1565 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
1566 | struct btrfs_fs_info *fs_info; |
1567 | struct btrfs_root *root; | |
1568 | struct btrfs_key key; | |
1569 | u64 end; | |
1570 | u64 total_found = 0; | |
1571 | u32 extent_count = 0; | |
1572 | int ret; | |
1573 | ||
1574 | block_group = caching_ctl->block_group; | |
1575 | fs_info = block_group->fs_info; | |
7939dd9f | 1576 | root = btrfs_free_space_root(block_group); |
a5ed9182 | 1577 | |
b3470b5d | 1578 | end = block_group->start + block_group->length; |
a5ed9182 OS |
1579 | |
1580 | while (1) { | |
d8ccbd21 FM |
1581 | u64 space_added; |
1582 | ||
a5ed9182 OS |
1583 | ret = btrfs_next_item(root, path); |
1584 | if (ret < 0) | |
1585 | goto out; | |
1586 | if (ret) | |
1587 | break; | |
1588 | ||
1589 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1590 | ||
1591 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1592 | break; | |
1593 | ||
1594 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
1595 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1596 | ||
3b9f0995 FM |
1597 | ret = btrfs_add_new_free_space(block_group, key.objectid, |
1598 | key.objectid + key.offset, | |
1599 | &space_added); | |
d8ccbd21 FM |
1600 | if (ret) |
1601 | goto out; | |
1602 | total_found += space_added; | |
a5ed9182 OS |
1603 | if (total_found > CACHING_CTL_WAKE_UP) { |
1604 | total_found = 0; | |
1605 | wake_up(&caching_ctl->wait); | |
1606 | } | |
1607 | extent_count++; | |
1608 | } | |
1609 | ||
1610 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1611 | btrfs_err(fs_info, |
1612 | "incorrect extent count for %llu; counted %u, expected %u", | |
b3470b5d | 1613 | block_group->start, extent_count, |
a5ed9182 OS |
1614 | expected_extent_count); |
1615 | ASSERT(0); | |
1616 | ret = -EIO; | |
1617 | goto out; | |
1618 | } | |
1619 | ||
a5ed9182 OS |
1620 | ret = 0; |
1621 | out: | |
1622 | return ret; | |
1623 | } | |
1624 | ||
1625 | int load_free_space_tree(struct btrfs_caching_control *caching_ctl) | |
1626 | { | |
32da5386 | 1627 | struct btrfs_block_group *block_group; |
a5ed9182 OS |
1628 | struct btrfs_free_space_info *info; |
1629 | struct btrfs_path *path; | |
1630 | u32 extent_count, flags; | |
1631 | int ret; | |
1632 | ||
1633 | block_group = caching_ctl->block_group; | |
a5ed9182 OS |
1634 | |
1635 | path = btrfs_alloc_path(); | |
1636 | if (!path) | |
1637 | return -ENOMEM; | |
1638 | ||
1639 | /* | |
1640 | * Just like caching_thread() doesn't want to deadlock on the extent | |
1641 | * tree, we don't want to deadlock on the free space tree. | |
1642 | */ | |
1643 | path->skip_locking = 1; | |
1644 | path->search_commit_root = 1; | |
7ce311d5 | 1645 | path->reada = READA_FORWARD; |
a5ed9182 | 1646 | |
2ccf545e | 1647 | info = search_free_space_info(NULL, block_group, path, 0); |
a5ed9182 OS |
1648 | if (IS_ERR(info)) { |
1649 | ret = PTR_ERR(info); | |
1650 | goto out; | |
1651 | } | |
1652 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
1653 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
1654 | ||
1655 | /* | |
1656 | * We left path pointing to the free space info item, so now | |
1657 | * load_free_space_foo can just iterate through the free space tree from | |
1658 | * there. | |
1659 | */ | |
1660 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) | |
1661 | ret = load_free_space_bitmaps(caching_ctl, path, extent_count); | |
1662 | else | |
1663 | ret = load_free_space_extents(caching_ctl, path, extent_count); | |
1664 | ||
1665 | out: | |
1666 | btrfs_free_path(path); | |
1667 | return ret; | |
1668 | } |