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Commit | Line | Data |
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6cbd5570 CM |
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 | ||
79154b1b | 19 | #include <linux/fs.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
34088780 | 21 | #include <linux/sched.h> |
d3c2fdcf | 22 | #include <linux/writeback.h> |
5f39d397 | 23 | #include <linux/pagemap.h> |
5f2cc086 | 24 | #include <linux/blkdev.h> |
79154b1b CM |
25 | #include "ctree.h" |
26 | #include "disk-io.h" | |
27 | #include "transaction.h" | |
925baedd | 28 | #include "locking.h" |
e02119d5 | 29 | #include "tree-log.h" |
79154b1b | 30 | |
0f7d52f4 CM |
31 | #define BTRFS_ROOT_TRANS_TAG 0 |
32 | ||
80b6794d | 33 | static noinline void put_transaction(struct btrfs_transaction *transaction) |
79154b1b | 34 | { |
13c5a93e JB |
35 | WARN_ON(atomic_read(&transaction->use_count) == 0); |
36 | if (atomic_dec_and_test(&transaction->use_count)) { | |
2c90e5d6 CM |
37 | memset(transaction, 0, sizeof(*transaction)); |
38 | kmem_cache_free(btrfs_transaction_cachep, transaction); | |
78fae27e | 39 | } |
79154b1b CM |
40 | } |
41 | ||
817d52f8 JB |
42 | static noinline void switch_commit_root(struct btrfs_root *root) |
43 | { | |
817d52f8 JB |
44 | free_extent_buffer(root->commit_root); |
45 | root->commit_root = btrfs_root_node(root); | |
817d52f8 JB |
46 | } |
47 | ||
d352ac68 CM |
48 | /* |
49 | * either allocate a new transaction or hop into the existing one | |
50 | */ | |
80b6794d | 51 | static noinline int join_transaction(struct btrfs_root *root) |
79154b1b CM |
52 | { |
53 | struct btrfs_transaction *cur_trans; | |
54 | cur_trans = root->fs_info->running_transaction; | |
55 | if (!cur_trans) { | |
2c90e5d6 CM |
56 | cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, |
57 | GFP_NOFS); | |
db5b493a TI |
58 | if (!cur_trans) |
59 | return -ENOMEM; | |
0f7d52f4 | 60 | root->fs_info->generation++; |
13c5a93e | 61 | atomic_set(&cur_trans->num_writers, 1); |
15ee9bc7 | 62 | cur_trans->num_joined = 0; |
0f7d52f4 | 63 | cur_trans->transid = root->fs_info->generation; |
79154b1b CM |
64 | init_waitqueue_head(&cur_trans->writer_wait); |
65 | init_waitqueue_head(&cur_trans->commit_wait); | |
66 | cur_trans->in_commit = 0; | |
f9295749 | 67 | cur_trans->blocked = 0; |
13c5a93e | 68 | atomic_set(&cur_trans->use_count, 1); |
79154b1b | 69 | cur_trans->commit_done = 0; |
08607c1b | 70 | cur_trans->start_time = get_seconds(); |
56bec294 | 71 | |
6bef4d31 | 72 | cur_trans->delayed_refs.root = RB_ROOT; |
56bec294 | 73 | cur_trans->delayed_refs.num_entries = 0; |
c3e69d58 CM |
74 | cur_trans->delayed_refs.num_heads_ready = 0; |
75 | cur_trans->delayed_refs.num_heads = 0; | |
56bec294 | 76 | cur_trans->delayed_refs.flushing = 0; |
c3e69d58 | 77 | cur_trans->delayed_refs.run_delayed_start = 0; |
56bec294 CM |
78 | spin_lock_init(&cur_trans->delayed_refs.lock); |
79 | ||
3063d29f | 80 | INIT_LIST_HEAD(&cur_trans->pending_snapshots); |
8fd17795 | 81 | list_add_tail(&cur_trans->list, &root->fs_info->trans_list); |
d1310b2e | 82 | extent_io_tree_init(&cur_trans->dirty_pages, |
5f39d397 CM |
83 | root->fs_info->btree_inode->i_mapping, |
84 | GFP_NOFS); | |
48ec2cf8 CM |
85 | spin_lock(&root->fs_info->new_trans_lock); |
86 | root->fs_info->running_transaction = cur_trans; | |
87 | spin_unlock(&root->fs_info->new_trans_lock); | |
15ee9bc7 | 88 | } else { |
13c5a93e | 89 | atomic_inc(&cur_trans->num_writers); |
15ee9bc7 | 90 | cur_trans->num_joined++; |
79154b1b | 91 | } |
15ee9bc7 | 92 | |
79154b1b CM |
93 | return 0; |
94 | } | |
95 | ||
d352ac68 | 96 | /* |
d397712b CM |
97 | * this does all the record keeping required to make sure that a reference |
98 | * counted root is properly recorded in a given transaction. This is required | |
99 | * to make sure the old root from before we joined the transaction is deleted | |
100 | * when the transaction commits | |
d352ac68 | 101 | */ |
5d4f98a2 YZ |
102 | static noinline int record_root_in_trans(struct btrfs_trans_handle *trans, |
103 | struct btrfs_root *root) | |
6702ed49 | 104 | { |
5d4f98a2 | 105 | if (root->ref_cows && root->last_trans < trans->transid) { |
6702ed49 | 106 | WARN_ON(root == root->fs_info->extent_root); |
5d4f98a2 YZ |
107 | WARN_ON(root->commit_root != root->node); |
108 | ||
109 | radix_tree_tag_set(&root->fs_info->fs_roots_radix, | |
110 | (unsigned long)root->root_key.objectid, | |
111 | BTRFS_ROOT_TRANS_TAG); | |
112 | root->last_trans = trans->transid; | |
113 | btrfs_init_reloc_root(trans, root); | |
114 | } | |
115 | return 0; | |
116 | } | |
bcc63abb | 117 | |
5d4f98a2 YZ |
118 | int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, |
119 | struct btrfs_root *root) | |
120 | { | |
121 | if (!root->ref_cows) | |
122 | return 0; | |
bcc63abb | 123 | |
5d4f98a2 YZ |
124 | mutex_lock(&root->fs_info->trans_mutex); |
125 | if (root->last_trans == trans->transid) { | |
126 | mutex_unlock(&root->fs_info->trans_mutex); | |
127 | return 0; | |
6702ed49 | 128 | } |
5d4f98a2 YZ |
129 | |
130 | record_root_in_trans(trans, root); | |
131 | mutex_unlock(&root->fs_info->trans_mutex); | |
6702ed49 CM |
132 | return 0; |
133 | } | |
134 | ||
d352ac68 CM |
135 | /* wait for commit against the current transaction to become unblocked |
136 | * when this is done, it is safe to start a new transaction, but the current | |
137 | * transaction might not be fully on disk. | |
138 | */ | |
37d1aeee | 139 | static void wait_current_trans(struct btrfs_root *root) |
79154b1b | 140 | { |
f9295749 | 141 | struct btrfs_transaction *cur_trans; |
79154b1b | 142 | |
f9295749 | 143 | cur_trans = root->fs_info->running_transaction; |
37d1aeee | 144 | if (cur_trans && cur_trans->blocked) { |
f9295749 | 145 | DEFINE_WAIT(wait); |
13c5a93e | 146 | atomic_inc(&cur_trans->use_count); |
d397712b | 147 | while (1) { |
f9295749 CM |
148 | prepare_to_wait(&root->fs_info->transaction_wait, &wait, |
149 | TASK_UNINTERRUPTIBLE); | |
471fa17d | 150 | if (!cur_trans->blocked) |
f9295749 | 151 | break; |
471fa17d ZL |
152 | mutex_unlock(&root->fs_info->trans_mutex); |
153 | schedule(); | |
154 | mutex_lock(&root->fs_info->trans_mutex); | |
f9295749 | 155 | } |
471fa17d | 156 | finish_wait(&root->fs_info->transaction_wait, &wait); |
f9295749 CM |
157 | put_transaction(cur_trans); |
158 | } | |
37d1aeee CM |
159 | } |
160 | ||
249ac1e5 JB |
161 | enum btrfs_trans_type { |
162 | TRANS_START, | |
163 | TRANS_JOIN, | |
164 | TRANS_USERSPACE, | |
0af3d00b | 165 | TRANS_JOIN_NOLOCK, |
249ac1e5 JB |
166 | }; |
167 | ||
a22285a6 YZ |
168 | static int may_wait_transaction(struct btrfs_root *root, int type) |
169 | { | |
170 | if (!root->fs_info->log_root_recovering && | |
171 | ((type == TRANS_START && !root->fs_info->open_ioctl_trans) || | |
172 | type == TRANS_USERSPACE)) | |
173 | return 1; | |
174 | return 0; | |
175 | } | |
176 | ||
e02119d5 | 177 | static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, |
a22285a6 | 178 | u64 num_items, int type) |
37d1aeee | 179 | { |
a22285a6 YZ |
180 | struct btrfs_trans_handle *h; |
181 | struct btrfs_transaction *cur_trans; | |
06d5a589 | 182 | int retries = 0; |
37d1aeee | 183 | int ret; |
acce952b | 184 | |
185 | if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) | |
186 | return ERR_PTR(-EROFS); | |
a22285a6 YZ |
187 | again: |
188 | h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); | |
189 | if (!h) | |
190 | return ERR_PTR(-ENOMEM); | |
37d1aeee | 191 | |
0af3d00b JB |
192 | if (type != TRANS_JOIN_NOLOCK) |
193 | mutex_lock(&root->fs_info->trans_mutex); | |
a22285a6 | 194 | if (may_wait_transaction(root, type)) |
37d1aeee | 195 | wait_current_trans(root); |
a22285a6 | 196 | |
79154b1b | 197 | ret = join_transaction(root); |
db5b493a | 198 | if (ret < 0) { |
6e8df2ae | 199 | kmem_cache_free(btrfs_trans_handle_cachep, h); |
db5b493a TI |
200 | if (type != TRANS_JOIN_NOLOCK) |
201 | mutex_unlock(&root->fs_info->trans_mutex); | |
202 | return ERR_PTR(ret); | |
203 | } | |
0f7d52f4 | 204 | |
a22285a6 | 205 | cur_trans = root->fs_info->running_transaction; |
13c5a93e | 206 | atomic_inc(&cur_trans->use_count); |
0af3d00b JB |
207 | if (type != TRANS_JOIN_NOLOCK) |
208 | mutex_unlock(&root->fs_info->trans_mutex); | |
a22285a6 YZ |
209 | |
210 | h->transid = cur_trans->transid; | |
211 | h->transaction = cur_trans; | |
79154b1b | 212 | h->blocks_used = 0; |
d2fb3437 | 213 | h->block_group = 0; |
a22285a6 | 214 | h->bytes_reserved = 0; |
56bec294 | 215 | h->delayed_ref_updates = 0; |
f0486c68 | 216 | h->block_rsv = NULL; |
b7ec40d7 | 217 | |
a22285a6 YZ |
218 | smp_mb(); |
219 | if (cur_trans->blocked && may_wait_transaction(root, type)) { | |
220 | btrfs_commit_transaction(h, root); | |
221 | goto again; | |
222 | } | |
223 | ||
224 | if (num_items > 0) { | |
8bb8ab2e | 225 | ret = btrfs_trans_reserve_metadata(h, root, num_items); |
06d5a589 JB |
226 | if (ret == -EAGAIN && !retries) { |
227 | retries++; | |
a22285a6 YZ |
228 | btrfs_commit_transaction(h, root); |
229 | goto again; | |
06d5a589 JB |
230 | } else if (ret == -EAGAIN) { |
231 | /* | |
232 | * We have already retried and got EAGAIN, so really we | |
233 | * don't have space, so set ret to -ENOSPC. | |
234 | */ | |
235 | ret = -ENOSPC; | |
a22285a6 | 236 | } |
06d5a589 | 237 | |
a22285a6 YZ |
238 | if (ret < 0) { |
239 | btrfs_end_transaction(h, root); | |
240 | return ERR_PTR(ret); | |
241 | } | |
242 | } | |
9ed74f2d | 243 | |
0af3d00b JB |
244 | if (type != TRANS_JOIN_NOLOCK) |
245 | mutex_lock(&root->fs_info->trans_mutex); | |
5d4f98a2 | 246 | record_root_in_trans(h, root); |
0af3d00b JB |
247 | if (type != TRANS_JOIN_NOLOCK) |
248 | mutex_unlock(&root->fs_info->trans_mutex); | |
a22285a6 YZ |
249 | |
250 | if (!current->journal_info && type != TRANS_USERSPACE) | |
251 | current->journal_info = h; | |
79154b1b CM |
252 | return h; |
253 | } | |
254 | ||
f9295749 | 255 | struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, |
a22285a6 | 256 | int num_items) |
f9295749 | 257 | { |
a22285a6 | 258 | return start_transaction(root, num_items, TRANS_START); |
f9295749 CM |
259 | } |
260 | struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, | |
261 | int num_blocks) | |
262 | { | |
a22285a6 | 263 | return start_transaction(root, 0, TRANS_JOIN); |
f9295749 CM |
264 | } |
265 | ||
0af3d00b JB |
266 | struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root, |
267 | int num_blocks) | |
268 | { | |
269 | return start_transaction(root, 0, TRANS_JOIN_NOLOCK); | |
270 | } | |
271 | ||
9ca9ee09 SW |
272 | struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r, |
273 | int num_blocks) | |
274 | { | |
a22285a6 | 275 | return start_transaction(r, 0, TRANS_USERSPACE); |
9ca9ee09 SW |
276 | } |
277 | ||
d352ac68 | 278 | /* wait for a transaction commit to be fully complete */ |
89ce8a63 CM |
279 | static noinline int wait_for_commit(struct btrfs_root *root, |
280 | struct btrfs_transaction *commit) | |
281 | { | |
282 | DEFINE_WAIT(wait); | |
283 | mutex_lock(&root->fs_info->trans_mutex); | |
d397712b | 284 | while (!commit->commit_done) { |
89ce8a63 CM |
285 | prepare_to_wait(&commit->commit_wait, &wait, |
286 | TASK_UNINTERRUPTIBLE); | |
287 | if (commit->commit_done) | |
288 | break; | |
289 | mutex_unlock(&root->fs_info->trans_mutex); | |
290 | schedule(); | |
291 | mutex_lock(&root->fs_info->trans_mutex); | |
292 | } | |
293 | mutex_unlock(&root->fs_info->trans_mutex); | |
294 | finish_wait(&commit->commit_wait, &wait); | |
295 | return 0; | |
296 | } | |
297 | ||
46204592 SW |
298 | int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid) |
299 | { | |
300 | struct btrfs_transaction *cur_trans = NULL, *t; | |
301 | int ret; | |
302 | ||
303 | mutex_lock(&root->fs_info->trans_mutex); | |
304 | ||
305 | ret = 0; | |
306 | if (transid) { | |
307 | if (transid <= root->fs_info->last_trans_committed) | |
308 | goto out_unlock; | |
309 | ||
310 | /* find specified transaction */ | |
311 | list_for_each_entry(t, &root->fs_info->trans_list, list) { | |
312 | if (t->transid == transid) { | |
313 | cur_trans = t; | |
314 | break; | |
315 | } | |
316 | if (t->transid > transid) | |
317 | break; | |
318 | } | |
319 | ret = -EINVAL; | |
320 | if (!cur_trans) | |
321 | goto out_unlock; /* bad transid */ | |
322 | } else { | |
323 | /* find newest transaction that is committing | committed */ | |
324 | list_for_each_entry_reverse(t, &root->fs_info->trans_list, | |
325 | list) { | |
326 | if (t->in_commit) { | |
327 | if (t->commit_done) | |
328 | goto out_unlock; | |
329 | cur_trans = t; | |
330 | break; | |
331 | } | |
332 | } | |
333 | if (!cur_trans) | |
334 | goto out_unlock; /* nothing committing|committed */ | |
335 | } | |
336 | ||
13c5a93e | 337 | atomic_inc(&cur_trans->use_count); |
46204592 SW |
338 | mutex_unlock(&root->fs_info->trans_mutex); |
339 | ||
340 | wait_for_commit(root, cur_trans); | |
341 | ||
342 | mutex_lock(&root->fs_info->trans_mutex); | |
343 | put_transaction(cur_trans); | |
344 | ret = 0; | |
345 | out_unlock: | |
346 | mutex_unlock(&root->fs_info->trans_mutex); | |
347 | return ret; | |
348 | } | |
349 | ||
5d4f98a2 | 350 | #if 0 |
d352ac68 | 351 | /* |
d397712b CM |
352 | * rate limit against the drop_snapshot code. This helps to slow down new |
353 | * operations if the drop_snapshot code isn't able to keep up. | |
d352ac68 | 354 | */ |
37d1aeee | 355 | static void throttle_on_drops(struct btrfs_root *root) |
ab78c84d CM |
356 | { |
357 | struct btrfs_fs_info *info = root->fs_info; | |
2dd3e67b | 358 | int harder_count = 0; |
ab78c84d | 359 | |
2dd3e67b | 360 | harder: |
ab78c84d CM |
361 | if (atomic_read(&info->throttles)) { |
362 | DEFINE_WAIT(wait); | |
363 | int thr; | |
ab78c84d CM |
364 | thr = atomic_read(&info->throttle_gen); |
365 | ||
366 | do { | |
367 | prepare_to_wait(&info->transaction_throttle, | |
368 | &wait, TASK_UNINTERRUPTIBLE); | |
369 | if (!atomic_read(&info->throttles)) { | |
370 | finish_wait(&info->transaction_throttle, &wait); | |
371 | break; | |
372 | } | |
373 | schedule(); | |
374 | finish_wait(&info->transaction_throttle, &wait); | |
375 | } while (thr == atomic_read(&info->throttle_gen)); | |
2dd3e67b CM |
376 | harder_count++; |
377 | ||
378 | if (root->fs_info->total_ref_cache_size > 1 * 1024 * 1024 && | |
379 | harder_count < 2) | |
380 | goto harder; | |
381 | ||
382 | if (root->fs_info->total_ref_cache_size > 5 * 1024 * 1024 && | |
383 | harder_count < 10) | |
384 | goto harder; | |
385 | ||
386 | if (root->fs_info->total_ref_cache_size > 10 * 1024 * 1024 && | |
387 | harder_count < 20) | |
388 | goto harder; | |
ab78c84d CM |
389 | } |
390 | } | |
5d4f98a2 | 391 | #endif |
ab78c84d | 392 | |
37d1aeee CM |
393 | void btrfs_throttle(struct btrfs_root *root) |
394 | { | |
395 | mutex_lock(&root->fs_info->trans_mutex); | |
9ca9ee09 SW |
396 | if (!root->fs_info->open_ioctl_trans) |
397 | wait_current_trans(root); | |
37d1aeee | 398 | mutex_unlock(&root->fs_info->trans_mutex); |
37d1aeee CM |
399 | } |
400 | ||
8929ecfa YZ |
401 | static int should_end_transaction(struct btrfs_trans_handle *trans, |
402 | struct btrfs_root *root) | |
403 | { | |
404 | int ret; | |
405 | ret = btrfs_block_rsv_check(trans, root, | |
406 | &root->fs_info->global_block_rsv, 0, 5); | |
407 | return ret ? 1 : 0; | |
408 | } | |
409 | ||
410 | int btrfs_should_end_transaction(struct btrfs_trans_handle *trans, | |
411 | struct btrfs_root *root) | |
412 | { | |
413 | struct btrfs_transaction *cur_trans = trans->transaction; | |
414 | int updates; | |
415 | ||
416 | if (cur_trans->blocked || cur_trans->delayed_refs.flushing) | |
417 | return 1; | |
418 | ||
419 | updates = trans->delayed_ref_updates; | |
420 | trans->delayed_ref_updates = 0; | |
421 | if (updates) | |
422 | btrfs_run_delayed_refs(trans, root, updates); | |
423 | ||
424 | return should_end_transaction(trans, root); | |
425 | } | |
426 | ||
89ce8a63 | 427 | static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, |
0af3d00b | 428 | struct btrfs_root *root, int throttle, int lock) |
79154b1b | 429 | { |
8929ecfa | 430 | struct btrfs_transaction *cur_trans = trans->transaction; |
ab78c84d | 431 | struct btrfs_fs_info *info = root->fs_info; |
c3e69d58 CM |
432 | int count = 0; |
433 | ||
434 | while (count < 4) { | |
435 | unsigned long cur = trans->delayed_ref_updates; | |
436 | trans->delayed_ref_updates = 0; | |
437 | if (cur && | |
438 | trans->transaction->delayed_refs.num_heads_ready > 64) { | |
439 | trans->delayed_ref_updates = 0; | |
b7ec40d7 CM |
440 | |
441 | /* | |
442 | * do a full flush if the transaction is trying | |
443 | * to close | |
444 | */ | |
445 | if (trans->transaction->delayed_refs.flushing) | |
446 | cur = 0; | |
c3e69d58 CM |
447 | btrfs_run_delayed_refs(trans, root, cur); |
448 | } else { | |
449 | break; | |
450 | } | |
451 | count++; | |
56bec294 CM |
452 | } |
453 | ||
a22285a6 YZ |
454 | btrfs_trans_release_metadata(trans, root); |
455 | ||
0af3d00b | 456 | if (lock && !root->fs_info->open_ioctl_trans && |
8929ecfa YZ |
457 | should_end_transaction(trans, root)) |
458 | trans->transaction->blocked = 1; | |
459 | ||
0af3d00b | 460 | if (lock && cur_trans->blocked && !cur_trans->in_commit) { |
8929ecfa YZ |
461 | if (throttle) |
462 | return btrfs_commit_transaction(trans, root); | |
463 | else | |
464 | wake_up_process(info->transaction_kthread); | |
465 | } | |
466 | ||
8929ecfa | 467 | WARN_ON(cur_trans != info->running_transaction); |
13c5a93e JB |
468 | WARN_ON(atomic_read(&cur_trans->num_writers) < 1); |
469 | atomic_dec(&cur_trans->num_writers); | |
89ce8a63 | 470 | |
99d16cbc | 471 | smp_mb(); |
79154b1b CM |
472 | if (waitqueue_active(&cur_trans->writer_wait)) |
473 | wake_up(&cur_trans->writer_wait); | |
79154b1b | 474 | put_transaction(cur_trans); |
9ed74f2d JB |
475 | |
476 | if (current->journal_info == trans) | |
477 | current->journal_info = NULL; | |
d6025579 | 478 | memset(trans, 0, sizeof(*trans)); |
2c90e5d6 | 479 | kmem_cache_free(btrfs_trans_handle_cachep, trans); |
ab78c84d | 480 | |
24bbcf04 YZ |
481 | if (throttle) |
482 | btrfs_run_delayed_iputs(root); | |
483 | ||
79154b1b CM |
484 | return 0; |
485 | } | |
486 | ||
89ce8a63 CM |
487 | int btrfs_end_transaction(struct btrfs_trans_handle *trans, |
488 | struct btrfs_root *root) | |
489 | { | |
16cdcec7 MX |
490 | int ret; |
491 | ||
492 | ret = __btrfs_end_transaction(trans, root, 0, 1); | |
493 | if (ret) | |
494 | return ret; | |
495 | return 0; | |
89ce8a63 CM |
496 | } |
497 | ||
498 | int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, | |
499 | struct btrfs_root *root) | |
500 | { | |
16cdcec7 MX |
501 | int ret; |
502 | ||
503 | ret = __btrfs_end_transaction(trans, root, 1, 1); | |
504 | if (ret) | |
505 | return ret; | |
506 | return 0; | |
0af3d00b JB |
507 | } |
508 | ||
509 | int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, | |
510 | struct btrfs_root *root) | |
511 | { | |
16cdcec7 MX |
512 | int ret; |
513 | ||
514 | ret = __btrfs_end_transaction(trans, root, 0, 0); | |
515 | if (ret) | |
516 | return ret; | |
517 | return 0; | |
518 | } | |
519 | ||
520 | int btrfs_end_transaction_dmeta(struct btrfs_trans_handle *trans, | |
521 | struct btrfs_root *root) | |
522 | { | |
523 | return __btrfs_end_transaction(trans, root, 1, 1); | |
89ce8a63 CM |
524 | } |
525 | ||
d352ac68 CM |
526 | /* |
527 | * when btree blocks are allocated, they have some corresponding bits set for | |
528 | * them in one of two extent_io trees. This is used to make sure all of | |
690587d1 | 529 | * those extents are sent to disk but does not wait on them |
d352ac68 | 530 | */ |
690587d1 | 531 | int btrfs_write_marked_extents(struct btrfs_root *root, |
8cef4e16 | 532 | struct extent_io_tree *dirty_pages, int mark) |
79154b1b | 533 | { |
7c4452b9 | 534 | int ret; |
777e6bd7 | 535 | int err = 0; |
7c4452b9 CM |
536 | int werr = 0; |
537 | struct page *page; | |
7c4452b9 | 538 | struct inode *btree_inode = root->fs_info->btree_inode; |
777e6bd7 | 539 | u64 start = 0; |
5f39d397 CM |
540 | u64 end; |
541 | unsigned long index; | |
7c4452b9 | 542 | |
d397712b | 543 | while (1) { |
777e6bd7 | 544 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
8cef4e16 | 545 | mark); |
5f39d397 | 546 | if (ret) |
7c4452b9 | 547 | break; |
d397712b | 548 | while (start <= end) { |
777e6bd7 CM |
549 | cond_resched(); |
550 | ||
5f39d397 | 551 | index = start >> PAGE_CACHE_SHIFT; |
35ebb934 | 552 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; |
4bef0848 | 553 | page = find_get_page(btree_inode->i_mapping, index); |
7c4452b9 CM |
554 | if (!page) |
555 | continue; | |
4bef0848 CM |
556 | |
557 | btree_lock_page_hook(page); | |
558 | if (!page->mapping) { | |
559 | unlock_page(page); | |
560 | page_cache_release(page); | |
561 | continue; | |
562 | } | |
563 | ||
6702ed49 CM |
564 | if (PageWriteback(page)) { |
565 | if (PageDirty(page)) | |
566 | wait_on_page_writeback(page); | |
567 | else { | |
568 | unlock_page(page); | |
569 | page_cache_release(page); | |
570 | continue; | |
571 | } | |
572 | } | |
7c4452b9 CM |
573 | err = write_one_page(page, 0); |
574 | if (err) | |
575 | werr = err; | |
576 | page_cache_release(page); | |
577 | } | |
578 | } | |
690587d1 CM |
579 | if (err) |
580 | werr = err; | |
581 | return werr; | |
582 | } | |
583 | ||
584 | /* | |
585 | * when btree blocks are allocated, they have some corresponding bits set for | |
586 | * them in one of two extent_io trees. This is used to make sure all of | |
587 | * those extents are on disk for transaction or log commit. We wait | |
588 | * on all the pages and clear them from the dirty pages state tree | |
589 | */ | |
590 | int btrfs_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 591 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
592 | { |
593 | int ret; | |
594 | int err = 0; | |
595 | int werr = 0; | |
596 | struct page *page; | |
597 | struct inode *btree_inode = root->fs_info->btree_inode; | |
598 | u64 start = 0; | |
599 | u64 end; | |
600 | unsigned long index; | |
601 | ||
d397712b | 602 | while (1) { |
8cef4e16 YZ |
603 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
604 | mark); | |
777e6bd7 CM |
605 | if (ret) |
606 | break; | |
607 | ||
8cef4e16 | 608 | clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS); |
d397712b | 609 | while (start <= end) { |
777e6bd7 CM |
610 | index = start >> PAGE_CACHE_SHIFT; |
611 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; | |
612 | page = find_get_page(btree_inode->i_mapping, index); | |
613 | if (!page) | |
614 | continue; | |
615 | if (PageDirty(page)) { | |
4bef0848 CM |
616 | btree_lock_page_hook(page); |
617 | wait_on_page_writeback(page); | |
777e6bd7 CM |
618 | err = write_one_page(page, 0); |
619 | if (err) | |
620 | werr = err; | |
621 | } | |
105d931d | 622 | wait_on_page_writeback(page); |
777e6bd7 CM |
623 | page_cache_release(page); |
624 | cond_resched(); | |
625 | } | |
626 | } | |
7c4452b9 CM |
627 | if (err) |
628 | werr = err; | |
629 | return werr; | |
79154b1b CM |
630 | } |
631 | ||
690587d1 CM |
632 | /* |
633 | * when btree blocks are allocated, they have some corresponding bits set for | |
634 | * them in one of two extent_io trees. This is used to make sure all of | |
635 | * those extents are on disk for transaction or log commit | |
636 | */ | |
637 | int btrfs_write_and_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 638 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
639 | { |
640 | int ret; | |
641 | int ret2; | |
642 | ||
8cef4e16 YZ |
643 | ret = btrfs_write_marked_extents(root, dirty_pages, mark); |
644 | ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark); | |
690587d1 CM |
645 | return ret || ret2; |
646 | } | |
647 | ||
d0c803c4 CM |
648 | int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, |
649 | struct btrfs_root *root) | |
650 | { | |
651 | if (!trans || !trans->transaction) { | |
652 | struct inode *btree_inode; | |
653 | btree_inode = root->fs_info->btree_inode; | |
654 | return filemap_write_and_wait(btree_inode->i_mapping); | |
655 | } | |
656 | return btrfs_write_and_wait_marked_extents(root, | |
8cef4e16 YZ |
657 | &trans->transaction->dirty_pages, |
658 | EXTENT_DIRTY); | |
d0c803c4 CM |
659 | } |
660 | ||
d352ac68 CM |
661 | /* |
662 | * this is used to update the root pointer in the tree of tree roots. | |
663 | * | |
664 | * But, in the case of the extent allocation tree, updating the root | |
665 | * pointer may allocate blocks which may change the root of the extent | |
666 | * allocation tree. | |
667 | * | |
668 | * So, this loops and repeats and makes sure the cowonly root didn't | |
669 | * change while the root pointer was being updated in the metadata. | |
670 | */ | |
0b86a832 CM |
671 | static int update_cowonly_root(struct btrfs_trans_handle *trans, |
672 | struct btrfs_root *root) | |
79154b1b CM |
673 | { |
674 | int ret; | |
0b86a832 | 675 | u64 old_root_bytenr; |
86b9f2ec | 676 | u64 old_root_used; |
0b86a832 | 677 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
79154b1b | 678 | |
86b9f2ec | 679 | old_root_used = btrfs_root_used(&root->root_item); |
0b86a832 | 680 | btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 681 | |
d397712b | 682 | while (1) { |
0b86a832 | 683 | old_root_bytenr = btrfs_root_bytenr(&root->root_item); |
86b9f2ec YZ |
684 | if (old_root_bytenr == root->node->start && |
685 | old_root_used == btrfs_root_used(&root->root_item)) | |
79154b1b | 686 | break; |
87ef2bb4 | 687 | |
5d4f98a2 | 688 | btrfs_set_root_node(&root->root_item, root->node); |
79154b1b | 689 | ret = btrfs_update_root(trans, tree_root, |
0b86a832 CM |
690 | &root->root_key, |
691 | &root->root_item); | |
79154b1b | 692 | BUG_ON(ret); |
56bec294 | 693 | |
86b9f2ec | 694 | old_root_used = btrfs_root_used(&root->root_item); |
4a8c9a62 | 695 | ret = btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 696 | BUG_ON(ret); |
0b86a832 | 697 | } |
276e680d YZ |
698 | |
699 | if (root != root->fs_info->extent_root) | |
700 | switch_commit_root(root); | |
701 | ||
0b86a832 CM |
702 | return 0; |
703 | } | |
704 | ||
d352ac68 CM |
705 | /* |
706 | * update all the cowonly tree roots on disk | |
707 | */ | |
5d4f98a2 YZ |
708 | static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans, |
709 | struct btrfs_root *root) | |
0b86a832 CM |
710 | { |
711 | struct btrfs_fs_info *fs_info = root->fs_info; | |
712 | struct list_head *next; | |
84234f3a | 713 | struct extent_buffer *eb; |
56bec294 | 714 | int ret; |
84234f3a | 715 | |
56bec294 CM |
716 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
717 | BUG_ON(ret); | |
87ef2bb4 | 718 | |
84234f3a | 719 | eb = btrfs_lock_root_node(fs_info->tree_root); |
9fa8cfe7 | 720 | btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb); |
84234f3a YZ |
721 | btrfs_tree_unlock(eb); |
722 | free_extent_buffer(eb); | |
0b86a832 | 723 | |
56bec294 CM |
724 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
725 | BUG_ON(ret); | |
87ef2bb4 | 726 | |
d397712b | 727 | while (!list_empty(&fs_info->dirty_cowonly_roots)) { |
0b86a832 CM |
728 | next = fs_info->dirty_cowonly_roots.next; |
729 | list_del_init(next); | |
730 | root = list_entry(next, struct btrfs_root, dirty_list); | |
87ef2bb4 | 731 | |
0b86a832 | 732 | update_cowonly_root(trans, root); |
79154b1b | 733 | } |
276e680d YZ |
734 | |
735 | down_write(&fs_info->extent_commit_sem); | |
736 | switch_commit_root(fs_info->extent_root); | |
737 | up_write(&fs_info->extent_commit_sem); | |
738 | ||
79154b1b CM |
739 | return 0; |
740 | } | |
741 | ||
d352ac68 CM |
742 | /* |
743 | * dead roots are old snapshots that need to be deleted. This allocates | |
744 | * a dirty root struct and adds it into the list of dead roots that need to | |
745 | * be deleted | |
746 | */ | |
5d4f98a2 | 747 | int btrfs_add_dead_root(struct btrfs_root *root) |
5eda7b5e | 748 | { |
b48652c1 | 749 | mutex_lock(&root->fs_info->trans_mutex); |
5d4f98a2 | 750 | list_add(&root->root_list, &root->fs_info->dead_roots); |
b48652c1 | 751 | mutex_unlock(&root->fs_info->trans_mutex); |
5eda7b5e CM |
752 | return 0; |
753 | } | |
754 | ||
d352ac68 | 755 | /* |
5d4f98a2 | 756 | * update all the cowonly tree roots on disk |
d352ac68 | 757 | */ |
5d4f98a2 YZ |
758 | static noinline int commit_fs_roots(struct btrfs_trans_handle *trans, |
759 | struct btrfs_root *root) | |
0f7d52f4 | 760 | { |
0f7d52f4 | 761 | struct btrfs_root *gang[8]; |
5d4f98a2 | 762 | struct btrfs_fs_info *fs_info = root->fs_info; |
0f7d52f4 CM |
763 | int i; |
764 | int ret; | |
54aa1f4d CM |
765 | int err = 0; |
766 | ||
d397712b | 767 | while (1) { |
5d4f98a2 YZ |
768 | ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix, |
769 | (void **)gang, 0, | |
0f7d52f4 CM |
770 | ARRAY_SIZE(gang), |
771 | BTRFS_ROOT_TRANS_TAG); | |
772 | if (ret == 0) | |
773 | break; | |
774 | for (i = 0; i < ret; i++) { | |
775 | root = gang[i]; | |
5d4f98a2 YZ |
776 | radix_tree_tag_clear(&fs_info->fs_roots_radix, |
777 | (unsigned long)root->root_key.objectid, | |
778 | BTRFS_ROOT_TRANS_TAG); | |
31153d81 | 779 | |
e02119d5 | 780 | btrfs_free_log(trans, root); |
5d4f98a2 | 781 | btrfs_update_reloc_root(trans, root); |
d68fc57b | 782 | btrfs_orphan_commit_root(trans, root); |
bcc63abb | 783 | |
978d910d | 784 | if (root->commit_root != root->node) { |
817d52f8 | 785 | switch_commit_root(root); |
978d910d YZ |
786 | btrfs_set_root_node(&root->root_item, |
787 | root->node); | |
788 | } | |
5d4f98a2 | 789 | |
5d4f98a2 | 790 | err = btrfs_update_root(trans, fs_info->tree_root, |
0f7d52f4 CM |
791 | &root->root_key, |
792 | &root->root_item); | |
54aa1f4d CM |
793 | if (err) |
794 | break; | |
0f7d52f4 CM |
795 | } |
796 | } | |
54aa1f4d | 797 | return err; |
0f7d52f4 CM |
798 | } |
799 | ||
d352ac68 CM |
800 | /* |
801 | * defrag a given btree. If cacheonly == 1, this won't read from the disk, | |
802 | * otherwise every leaf in the btree is read and defragged. | |
803 | */ | |
e9d0b13b CM |
804 | int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) |
805 | { | |
806 | struct btrfs_fs_info *info = root->fs_info; | |
e9d0b13b | 807 | struct btrfs_trans_handle *trans; |
8929ecfa | 808 | int ret; |
d3c2fdcf | 809 | unsigned long nr; |
e9d0b13b | 810 | |
8929ecfa | 811 | if (xchg(&root->defrag_running, 1)) |
e9d0b13b | 812 | return 0; |
8929ecfa | 813 | |
6b80053d | 814 | while (1) { |
8929ecfa YZ |
815 | trans = btrfs_start_transaction(root, 0); |
816 | if (IS_ERR(trans)) | |
817 | return PTR_ERR(trans); | |
818 | ||
e9d0b13b | 819 | ret = btrfs_defrag_leaves(trans, root, cacheonly); |
8929ecfa | 820 | |
d3c2fdcf | 821 | nr = trans->blocks_used; |
e9d0b13b | 822 | btrfs_end_transaction(trans, root); |
d3c2fdcf | 823 | btrfs_btree_balance_dirty(info->tree_root, nr); |
e9d0b13b CM |
824 | cond_resched(); |
825 | ||
3f157a2f | 826 | if (root->fs_info->closing || ret != -EAGAIN) |
e9d0b13b CM |
827 | break; |
828 | } | |
829 | root->defrag_running = 0; | |
8929ecfa | 830 | return ret; |
e9d0b13b CM |
831 | } |
832 | ||
2c47e605 | 833 | #if 0 |
b7ec40d7 CM |
834 | /* |
835 | * when dropping snapshots, we generate a ton of delayed refs, and it makes | |
836 | * sense not to join the transaction while it is trying to flush the current | |
837 | * queue of delayed refs out. | |
838 | * | |
839 | * This is used by the drop snapshot code only | |
840 | */ | |
841 | static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info) | |
842 | { | |
843 | DEFINE_WAIT(wait); | |
844 | ||
845 | mutex_lock(&info->trans_mutex); | |
846 | while (info->running_transaction && | |
847 | info->running_transaction->delayed_refs.flushing) { | |
848 | prepare_to_wait(&info->transaction_wait, &wait, | |
849 | TASK_UNINTERRUPTIBLE); | |
850 | mutex_unlock(&info->trans_mutex); | |
59bc5c75 | 851 | |
b7ec40d7 | 852 | schedule(); |
59bc5c75 | 853 | |
b7ec40d7 CM |
854 | mutex_lock(&info->trans_mutex); |
855 | finish_wait(&info->transaction_wait, &wait); | |
856 | } | |
857 | mutex_unlock(&info->trans_mutex); | |
858 | return 0; | |
859 | } | |
860 | ||
d352ac68 CM |
861 | /* |
862 | * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on | |
863 | * all of them | |
864 | */ | |
5d4f98a2 | 865 | int btrfs_drop_dead_root(struct btrfs_root *root) |
0f7d52f4 | 866 | { |
0f7d52f4 | 867 | struct btrfs_trans_handle *trans; |
5d4f98a2 | 868 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
d3c2fdcf | 869 | unsigned long nr; |
5d4f98a2 | 870 | int ret; |
58176a96 | 871 | |
5d4f98a2 YZ |
872 | while (1) { |
873 | /* | |
874 | * we don't want to jump in and create a bunch of | |
875 | * delayed refs if the transaction is starting to close | |
876 | */ | |
877 | wait_transaction_pre_flush(tree_root->fs_info); | |
878 | trans = btrfs_start_transaction(tree_root, 1); | |
a2135011 | 879 | |
5d4f98a2 YZ |
880 | /* |
881 | * we've joined a transaction, make sure it isn't | |
882 | * closing right now | |
883 | */ | |
884 | if (trans->transaction->delayed_refs.flushing) { | |
885 | btrfs_end_transaction(trans, tree_root); | |
886 | continue; | |
9f3a7427 | 887 | } |
58176a96 | 888 | |
5d4f98a2 YZ |
889 | ret = btrfs_drop_snapshot(trans, root); |
890 | if (ret != -EAGAIN) | |
891 | break; | |
a2135011 | 892 | |
5d4f98a2 YZ |
893 | ret = btrfs_update_root(trans, tree_root, |
894 | &root->root_key, | |
895 | &root->root_item); | |
896 | if (ret) | |
54aa1f4d | 897 | break; |
bcc63abb | 898 | |
d3c2fdcf | 899 | nr = trans->blocks_used; |
0f7d52f4 CM |
900 | ret = btrfs_end_transaction(trans, tree_root); |
901 | BUG_ON(ret); | |
5eda7b5e | 902 | |
d3c2fdcf | 903 | btrfs_btree_balance_dirty(tree_root, nr); |
4dc11904 | 904 | cond_resched(); |
0f7d52f4 | 905 | } |
5d4f98a2 YZ |
906 | BUG_ON(ret); |
907 | ||
908 | ret = btrfs_del_root(trans, tree_root, &root->root_key); | |
909 | BUG_ON(ret); | |
910 | ||
911 | nr = trans->blocks_used; | |
912 | ret = btrfs_end_transaction(trans, tree_root); | |
913 | BUG_ON(ret); | |
914 | ||
915 | free_extent_buffer(root->node); | |
916 | free_extent_buffer(root->commit_root); | |
917 | kfree(root); | |
918 | ||
919 | btrfs_btree_balance_dirty(tree_root, nr); | |
54aa1f4d | 920 | return ret; |
0f7d52f4 | 921 | } |
2c47e605 | 922 | #endif |
0f7d52f4 | 923 | |
d352ac68 CM |
924 | /* |
925 | * new snapshots need to be created at a very specific time in the | |
926 | * transaction commit. This does the actual creation | |
927 | */ | |
80b6794d | 928 | static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, |
3063d29f CM |
929 | struct btrfs_fs_info *fs_info, |
930 | struct btrfs_pending_snapshot *pending) | |
931 | { | |
932 | struct btrfs_key key; | |
80b6794d | 933 | struct btrfs_root_item *new_root_item; |
3063d29f CM |
934 | struct btrfs_root *tree_root = fs_info->tree_root; |
935 | struct btrfs_root *root = pending->root; | |
6bdb72de SW |
936 | struct btrfs_root *parent_root; |
937 | struct inode *parent_inode; | |
6a912213 | 938 | struct dentry *parent; |
a22285a6 | 939 | struct dentry *dentry; |
3063d29f | 940 | struct extent_buffer *tmp; |
925baedd | 941 | struct extent_buffer *old; |
3063d29f | 942 | int ret; |
d68fc57b | 943 | u64 to_reserve = 0; |
6bdb72de | 944 | u64 index = 0; |
a22285a6 | 945 | u64 objectid; |
b83cc969 | 946 | u64 root_flags; |
3063d29f | 947 | |
80b6794d CM |
948 | new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); |
949 | if (!new_root_item) { | |
a22285a6 | 950 | pending->error = -ENOMEM; |
80b6794d CM |
951 | goto fail; |
952 | } | |
a22285a6 | 953 | |
3063d29f | 954 | ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); |
a22285a6 YZ |
955 | if (ret) { |
956 | pending->error = ret; | |
3063d29f | 957 | goto fail; |
a22285a6 | 958 | } |
3063d29f | 959 | |
3fd0a558 | 960 | btrfs_reloc_pre_snapshot(trans, pending, &to_reserve); |
d68fc57b YZ |
961 | btrfs_orphan_pre_snapshot(trans, pending, &to_reserve); |
962 | ||
963 | if (to_reserve > 0) { | |
964 | ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv, | |
8bb8ab2e | 965 | to_reserve); |
d68fc57b YZ |
966 | if (ret) { |
967 | pending->error = ret; | |
968 | goto fail; | |
969 | } | |
970 | } | |
971 | ||
3063d29f | 972 | key.objectid = objectid; |
a22285a6 YZ |
973 | key.offset = (u64)-1; |
974 | key.type = BTRFS_ROOT_ITEM_KEY; | |
3063d29f | 975 | |
a22285a6 | 976 | trans->block_rsv = &pending->block_rsv; |
3de4586c | 977 | |
a22285a6 | 978 | dentry = pending->dentry; |
6a912213 JB |
979 | parent = dget_parent(dentry); |
980 | parent_inode = parent->d_inode; | |
a22285a6 | 981 | parent_root = BTRFS_I(parent_inode)->root; |
6bdb72de | 982 | record_root_in_trans(trans, parent_root); |
a22285a6 | 983 | |
3063d29f CM |
984 | /* |
985 | * insert the directory item | |
986 | */ | |
3de4586c | 987 | ret = btrfs_set_inode_index(parent_inode, &index); |
6bdb72de | 988 | BUG_ON(ret); |
0660b5af | 989 | ret = btrfs_insert_dir_item(trans, parent_root, |
a22285a6 | 990 | dentry->d_name.name, dentry->d_name.len, |
16cdcec7 | 991 | parent_inode, &key, |
a22285a6 | 992 | BTRFS_FT_DIR, index); |
6bdb72de | 993 | BUG_ON(ret); |
0660b5af | 994 | |
a22285a6 YZ |
995 | btrfs_i_size_write(parent_inode, parent_inode->i_size + |
996 | dentry->d_name.len * 2); | |
52c26179 YZ |
997 | ret = btrfs_update_inode(trans, parent_root, parent_inode); |
998 | BUG_ON(ret); | |
999 | ||
6bdb72de SW |
1000 | record_root_in_trans(trans, root); |
1001 | btrfs_set_root_last_snapshot(&root->root_item, trans->transid); | |
1002 | memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); | |
08fe4db1 | 1003 | btrfs_check_and_init_root_item(new_root_item); |
6bdb72de | 1004 | |
b83cc969 LZ |
1005 | root_flags = btrfs_root_flags(new_root_item); |
1006 | if (pending->readonly) | |
1007 | root_flags |= BTRFS_ROOT_SUBVOL_RDONLY; | |
1008 | else | |
1009 | root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY; | |
1010 | btrfs_set_root_flags(new_root_item, root_flags); | |
1011 | ||
6bdb72de SW |
1012 | old = btrfs_lock_root_node(root); |
1013 | btrfs_cow_block(trans, root, old, NULL, 0, &old); | |
1014 | btrfs_set_lock_blocking(old); | |
1015 | ||
1016 | btrfs_copy_root(trans, root, old, &tmp, objectid); | |
1017 | btrfs_tree_unlock(old); | |
1018 | free_extent_buffer(old); | |
1019 | ||
1020 | btrfs_set_root_node(new_root_item, tmp); | |
a22285a6 YZ |
1021 | /* record when the snapshot was created in key.offset */ |
1022 | key.offset = trans->transid; | |
1023 | ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); | |
6bdb72de SW |
1024 | btrfs_tree_unlock(tmp); |
1025 | free_extent_buffer(tmp); | |
a22285a6 | 1026 | BUG_ON(ret); |
6bdb72de | 1027 | |
a22285a6 YZ |
1028 | /* |
1029 | * insert root back/forward references | |
1030 | */ | |
1031 | ret = btrfs_add_root_ref(trans, tree_root, objectid, | |
0660b5af | 1032 | parent_root->root_key.objectid, |
a22285a6 YZ |
1033 | parent_inode->i_ino, index, |
1034 | dentry->d_name.name, dentry->d_name.len); | |
0660b5af | 1035 | BUG_ON(ret); |
6a912213 | 1036 | dput(parent); |
0660b5af | 1037 | |
a22285a6 YZ |
1038 | key.offset = (u64)-1; |
1039 | pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); | |
1040 | BUG_ON(IS_ERR(pending->snap)); | |
d68fc57b | 1041 | |
3fd0a558 | 1042 | btrfs_reloc_post_snapshot(trans, pending); |
d68fc57b | 1043 | btrfs_orphan_post_snapshot(trans, pending); |
3063d29f | 1044 | fail: |
6bdb72de | 1045 | kfree(new_root_item); |
a22285a6 YZ |
1046 | btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); |
1047 | return 0; | |
3063d29f CM |
1048 | } |
1049 | ||
d352ac68 CM |
1050 | /* |
1051 | * create all the snapshots we've scheduled for creation | |
1052 | */ | |
80b6794d CM |
1053 | static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, |
1054 | struct btrfs_fs_info *fs_info) | |
3de4586c CM |
1055 | { |
1056 | struct btrfs_pending_snapshot *pending; | |
1057 | struct list_head *head = &trans->transaction->pending_snapshots; | |
3de4586c CM |
1058 | int ret; |
1059 | ||
c6e30871 | 1060 | list_for_each_entry(pending, head, list) { |
16cdcec7 MX |
1061 | /* |
1062 | * We must deal with the delayed items before creating | |
1063 | * snapshots, or we will create a snapthot with inconsistent | |
1064 | * information. | |
1065 | */ | |
1066 | ret = btrfs_run_delayed_items(trans, fs_info->fs_root); | |
1067 | BUG_ON(ret); | |
1068 | ||
3de4586c CM |
1069 | ret = create_pending_snapshot(trans, fs_info, pending); |
1070 | BUG_ON(ret); | |
1071 | } | |
1072 | return 0; | |
1073 | } | |
1074 | ||
5d4f98a2 YZ |
1075 | static void update_super_roots(struct btrfs_root *root) |
1076 | { | |
1077 | struct btrfs_root_item *root_item; | |
1078 | struct btrfs_super_block *super; | |
1079 | ||
1080 | super = &root->fs_info->super_copy; | |
1081 | ||
1082 | root_item = &root->fs_info->chunk_root->root_item; | |
1083 | super->chunk_root = root_item->bytenr; | |
1084 | super->chunk_root_generation = root_item->generation; | |
1085 | super->chunk_root_level = root_item->level; | |
1086 | ||
1087 | root_item = &root->fs_info->tree_root->root_item; | |
1088 | super->root = root_item->bytenr; | |
1089 | super->generation = root_item->generation; | |
1090 | super->root_level = root_item->level; | |
0af3d00b JB |
1091 | if (super->cache_generation != 0 || btrfs_test_opt(root, SPACE_CACHE)) |
1092 | super->cache_generation = root_item->generation; | |
5d4f98a2 YZ |
1093 | } |
1094 | ||
f36f3042 CM |
1095 | int btrfs_transaction_in_commit(struct btrfs_fs_info *info) |
1096 | { | |
1097 | int ret = 0; | |
1098 | spin_lock(&info->new_trans_lock); | |
1099 | if (info->running_transaction) | |
1100 | ret = info->running_transaction->in_commit; | |
1101 | spin_unlock(&info->new_trans_lock); | |
1102 | return ret; | |
1103 | } | |
1104 | ||
8929ecfa YZ |
1105 | int btrfs_transaction_blocked(struct btrfs_fs_info *info) |
1106 | { | |
1107 | int ret = 0; | |
1108 | spin_lock(&info->new_trans_lock); | |
1109 | if (info->running_transaction) | |
1110 | ret = info->running_transaction->blocked; | |
1111 | spin_unlock(&info->new_trans_lock); | |
1112 | return ret; | |
1113 | } | |
1114 | ||
bb9c12c9 SW |
1115 | /* |
1116 | * wait for the current transaction commit to start and block subsequent | |
1117 | * transaction joins | |
1118 | */ | |
1119 | static void wait_current_trans_commit_start(struct btrfs_root *root, | |
1120 | struct btrfs_transaction *trans) | |
1121 | { | |
1122 | DEFINE_WAIT(wait); | |
1123 | ||
1124 | if (trans->in_commit) | |
1125 | return; | |
1126 | ||
1127 | while (1) { | |
1128 | prepare_to_wait(&root->fs_info->transaction_blocked_wait, &wait, | |
1129 | TASK_UNINTERRUPTIBLE); | |
1130 | if (trans->in_commit) { | |
1131 | finish_wait(&root->fs_info->transaction_blocked_wait, | |
1132 | &wait); | |
1133 | break; | |
1134 | } | |
1135 | mutex_unlock(&root->fs_info->trans_mutex); | |
1136 | schedule(); | |
1137 | mutex_lock(&root->fs_info->trans_mutex); | |
1138 | finish_wait(&root->fs_info->transaction_blocked_wait, &wait); | |
1139 | } | |
1140 | } | |
1141 | ||
1142 | /* | |
1143 | * wait for the current transaction to start and then become unblocked. | |
1144 | * caller holds ref. | |
1145 | */ | |
1146 | static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root, | |
1147 | struct btrfs_transaction *trans) | |
1148 | { | |
1149 | DEFINE_WAIT(wait); | |
1150 | ||
1151 | if (trans->commit_done || (trans->in_commit && !trans->blocked)) | |
1152 | return; | |
1153 | ||
1154 | while (1) { | |
1155 | prepare_to_wait(&root->fs_info->transaction_wait, &wait, | |
1156 | TASK_UNINTERRUPTIBLE); | |
1157 | if (trans->commit_done || | |
1158 | (trans->in_commit && !trans->blocked)) { | |
1159 | finish_wait(&root->fs_info->transaction_wait, | |
1160 | &wait); | |
1161 | break; | |
1162 | } | |
1163 | mutex_unlock(&root->fs_info->trans_mutex); | |
1164 | schedule(); | |
1165 | mutex_lock(&root->fs_info->trans_mutex); | |
1166 | finish_wait(&root->fs_info->transaction_wait, | |
1167 | &wait); | |
1168 | } | |
1169 | } | |
1170 | ||
1171 | /* | |
1172 | * commit transactions asynchronously. once btrfs_commit_transaction_async | |
1173 | * returns, any subsequent transaction will not be allowed to join. | |
1174 | */ | |
1175 | struct btrfs_async_commit { | |
1176 | struct btrfs_trans_handle *newtrans; | |
1177 | struct btrfs_root *root; | |
1178 | struct delayed_work work; | |
1179 | }; | |
1180 | ||
1181 | static void do_async_commit(struct work_struct *work) | |
1182 | { | |
1183 | struct btrfs_async_commit *ac = | |
1184 | container_of(work, struct btrfs_async_commit, work.work); | |
1185 | ||
1186 | btrfs_commit_transaction(ac->newtrans, ac->root); | |
1187 | kfree(ac); | |
1188 | } | |
1189 | ||
1190 | int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans, | |
1191 | struct btrfs_root *root, | |
1192 | int wait_for_unblock) | |
1193 | { | |
1194 | struct btrfs_async_commit *ac; | |
1195 | struct btrfs_transaction *cur_trans; | |
1196 | ||
1197 | ac = kmalloc(sizeof(*ac), GFP_NOFS); | |
db5b493a TI |
1198 | if (!ac) |
1199 | return -ENOMEM; | |
bb9c12c9 SW |
1200 | |
1201 | INIT_DELAYED_WORK(&ac->work, do_async_commit); | |
1202 | ac->root = root; | |
1203 | ac->newtrans = btrfs_join_transaction(root, 0); | |
3612b495 TI |
1204 | if (IS_ERR(ac->newtrans)) { |
1205 | int err = PTR_ERR(ac->newtrans); | |
1206 | kfree(ac); | |
1207 | return err; | |
1208 | } | |
bb9c12c9 SW |
1209 | |
1210 | /* take transaction reference */ | |
1211 | mutex_lock(&root->fs_info->trans_mutex); | |
1212 | cur_trans = trans->transaction; | |
13c5a93e | 1213 | atomic_inc(&cur_trans->use_count); |
bb9c12c9 SW |
1214 | mutex_unlock(&root->fs_info->trans_mutex); |
1215 | ||
1216 | btrfs_end_transaction(trans, root); | |
1217 | schedule_delayed_work(&ac->work, 0); | |
1218 | ||
1219 | /* wait for transaction to start and unblock */ | |
1220 | mutex_lock(&root->fs_info->trans_mutex); | |
1221 | if (wait_for_unblock) | |
1222 | wait_current_trans_commit_start_and_unblock(root, cur_trans); | |
1223 | else | |
1224 | wait_current_trans_commit_start(root, cur_trans); | |
1225 | put_transaction(cur_trans); | |
1226 | mutex_unlock(&root->fs_info->trans_mutex); | |
1227 | ||
1228 | return 0; | |
1229 | } | |
1230 | ||
1231 | /* | |
1232 | * btrfs_transaction state sequence: | |
1233 | * in_commit = 0, blocked = 0 (initial) | |
1234 | * in_commit = 1, blocked = 1 | |
1235 | * blocked = 0 | |
1236 | * commit_done = 1 | |
1237 | */ | |
79154b1b CM |
1238 | int btrfs_commit_transaction(struct btrfs_trans_handle *trans, |
1239 | struct btrfs_root *root) | |
1240 | { | |
15ee9bc7 | 1241 | unsigned long joined = 0; |
79154b1b | 1242 | struct btrfs_transaction *cur_trans; |
8fd17795 | 1243 | struct btrfs_transaction *prev_trans = NULL; |
79154b1b | 1244 | DEFINE_WAIT(wait); |
15ee9bc7 | 1245 | int ret; |
89573b9c CM |
1246 | int should_grow = 0; |
1247 | unsigned long now = get_seconds(); | |
dccae999 | 1248 | int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT); |
79154b1b | 1249 | |
5a3f23d5 CM |
1250 | btrfs_run_ordered_operations(root, 0); |
1251 | ||
56bec294 CM |
1252 | /* make a pass through all the delayed refs we have so far |
1253 | * any runnings procs may add more while we are here | |
1254 | */ | |
1255 | ret = btrfs_run_delayed_refs(trans, root, 0); | |
1256 | BUG_ON(ret); | |
1257 | ||
a22285a6 YZ |
1258 | btrfs_trans_release_metadata(trans, root); |
1259 | ||
b7ec40d7 | 1260 | cur_trans = trans->transaction; |
56bec294 CM |
1261 | /* |
1262 | * set the flushing flag so procs in this transaction have to | |
1263 | * start sending their work down. | |
1264 | */ | |
b7ec40d7 | 1265 | cur_trans->delayed_refs.flushing = 1; |
56bec294 | 1266 | |
c3e69d58 | 1267 | ret = btrfs_run_delayed_refs(trans, root, 0); |
56bec294 CM |
1268 | BUG_ON(ret); |
1269 | ||
79154b1b | 1270 | mutex_lock(&root->fs_info->trans_mutex); |
b7ec40d7 | 1271 | if (cur_trans->in_commit) { |
13c5a93e | 1272 | atomic_inc(&cur_trans->use_count); |
ccd467d6 | 1273 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b | 1274 | btrfs_end_transaction(trans, root); |
ccd467d6 | 1275 | |
79154b1b CM |
1276 | ret = wait_for_commit(root, cur_trans); |
1277 | BUG_ON(ret); | |
15ee9bc7 JB |
1278 | |
1279 | mutex_lock(&root->fs_info->trans_mutex); | |
79154b1b | 1280 | put_transaction(cur_trans); |
15ee9bc7 JB |
1281 | mutex_unlock(&root->fs_info->trans_mutex); |
1282 | ||
79154b1b CM |
1283 | return 0; |
1284 | } | |
4313b399 | 1285 | |
2c90e5d6 | 1286 | trans->transaction->in_commit = 1; |
f9295749 | 1287 | trans->transaction->blocked = 1; |
bb9c12c9 SW |
1288 | wake_up(&root->fs_info->transaction_blocked_wait); |
1289 | ||
ccd467d6 CM |
1290 | if (cur_trans->list.prev != &root->fs_info->trans_list) { |
1291 | prev_trans = list_entry(cur_trans->list.prev, | |
1292 | struct btrfs_transaction, list); | |
1293 | if (!prev_trans->commit_done) { | |
13c5a93e | 1294 | atomic_inc(&prev_trans->use_count); |
ccd467d6 CM |
1295 | mutex_unlock(&root->fs_info->trans_mutex); |
1296 | ||
1297 | wait_for_commit(root, prev_trans); | |
ccd467d6 | 1298 | |
ccd467d6 | 1299 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1300 | put_transaction(prev_trans); |
ccd467d6 CM |
1301 | } |
1302 | } | |
15ee9bc7 | 1303 | |
89573b9c CM |
1304 | if (now < cur_trans->start_time || now - cur_trans->start_time < 1) |
1305 | should_grow = 1; | |
1306 | ||
15ee9bc7 | 1307 | do { |
7ea394f1 | 1308 | int snap_pending = 0; |
15ee9bc7 | 1309 | joined = cur_trans->num_joined; |
7ea394f1 YZ |
1310 | if (!list_empty(&trans->transaction->pending_snapshots)) |
1311 | snap_pending = 1; | |
1312 | ||
2c90e5d6 | 1313 | WARN_ON(cur_trans != trans->transaction); |
79154b1b | 1314 | mutex_unlock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1315 | |
0bdb1db2 | 1316 | if (flush_on_commit || snap_pending) { |
24bbcf04 YZ |
1317 | btrfs_start_delalloc_inodes(root, 1); |
1318 | ret = btrfs_wait_ordered_extents(root, 0, 1); | |
ebecd3d9 | 1319 | BUG_ON(ret); |
7ea394f1 YZ |
1320 | } |
1321 | ||
16cdcec7 MX |
1322 | ret = btrfs_run_delayed_items(trans, root); |
1323 | BUG_ON(ret); | |
1324 | ||
5a3f23d5 CM |
1325 | /* |
1326 | * rename don't use btrfs_join_transaction, so, once we | |
1327 | * set the transaction to blocked above, we aren't going | |
1328 | * to get any new ordered operations. We can safely run | |
1329 | * it here and no for sure that nothing new will be added | |
1330 | * to the list | |
1331 | */ | |
1332 | btrfs_run_ordered_operations(root, 1); | |
1333 | ||
ed3b3d31 CM |
1334 | prepare_to_wait(&cur_trans->writer_wait, &wait, |
1335 | TASK_UNINTERRUPTIBLE); | |
1336 | ||
89573b9c | 1337 | smp_mb(); |
13c5a93e | 1338 | if (atomic_read(&cur_trans->num_writers) > 1) |
99d16cbc SW |
1339 | schedule_timeout(MAX_SCHEDULE_TIMEOUT); |
1340 | else if (should_grow) | |
1341 | schedule_timeout(1); | |
15ee9bc7 | 1342 | |
79154b1b | 1343 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1344 | finish_wait(&cur_trans->writer_wait, &wait); |
13c5a93e | 1345 | } while (atomic_read(&cur_trans->num_writers) > 1 || |
89573b9c | 1346 | (should_grow && cur_trans->num_joined != joined)); |
15ee9bc7 | 1347 | |
3063d29f CM |
1348 | ret = create_pending_snapshots(trans, root->fs_info); |
1349 | BUG_ON(ret); | |
1350 | ||
16cdcec7 MX |
1351 | ret = btrfs_run_delayed_items(trans, root); |
1352 | BUG_ON(ret); | |
1353 | ||
56bec294 CM |
1354 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
1355 | BUG_ON(ret); | |
1356 | ||
2c90e5d6 | 1357 | WARN_ON(cur_trans != trans->transaction); |
dc17ff8f | 1358 | |
e02119d5 CM |
1359 | /* btrfs_commit_tree_roots is responsible for getting the |
1360 | * various roots consistent with each other. Every pointer | |
1361 | * in the tree of tree roots has to point to the most up to date | |
1362 | * root for every subvolume and other tree. So, we have to keep | |
1363 | * the tree logging code from jumping in and changing any | |
1364 | * of the trees. | |
1365 | * | |
1366 | * At this point in the commit, there can't be any tree-log | |
1367 | * writers, but a little lower down we drop the trans mutex | |
1368 | * and let new people in. By holding the tree_log_mutex | |
1369 | * from now until after the super is written, we avoid races | |
1370 | * with the tree-log code. | |
1371 | */ | |
1372 | mutex_lock(&root->fs_info->tree_log_mutex); | |
1373 | ||
5d4f98a2 | 1374 | ret = commit_fs_roots(trans, root); |
54aa1f4d CM |
1375 | BUG_ON(ret); |
1376 | ||
5d4f98a2 | 1377 | /* commit_fs_roots gets rid of all the tree log roots, it is now |
e02119d5 CM |
1378 | * safe to free the root of tree log roots |
1379 | */ | |
1380 | btrfs_free_log_root_tree(trans, root->fs_info); | |
1381 | ||
5d4f98a2 | 1382 | ret = commit_cowonly_roots(trans, root); |
79154b1b | 1383 | BUG_ON(ret); |
54aa1f4d | 1384 | |
11833d66 YZ |
1385 | btrfs_prepare_extent_commit(trans, root); |
1386 | ||
78fae27e | 1387 | cur_trans = root->fs_info->running_transaction; |
cee36a03 | 1388 | spin_lock(&root->fs_info->new_trans_lock); |
78fae27e | 1389 | root->fs_info->running_transaction = NULL; |
cee36a03 | 1390 | spin_unlock(&root->fs_info->new_trans_lock); |
5d4f98a2 YZ |
1391 | |
1392 | btrfs_set_root_node(&root->fs_info->tree_root->root_item, | |
1393 | root->fs_info->tree_root->node); | |
817d52f8 | 1394 | switch_commit_root(root->fs_info->tree_root); |
5d4f98a2 YZ |
1395 | |
1396 | btrfs_set_root_node(&root->fs_info->chunk_root->root_item, | |
1397 | root->fs_info->chunk_root->node); | |
817d52f8 | 1398 | switch_commit_root(root->fs_info->chunk_root); |
5d4f98a2 YZ |
1399 | |
1400 | update_super_roots(root); | |
e02119d5 CM |
1401 | |
1402 | if (!root->fs_info->log_root_recovering) { | |
1403 | btrfs_set_super_log_root(&root->fs_info->super_copy, 0); | |
1404 | btrfs_set_super_log_root_level(&root->fs_info->super_copy, 0); | |
1405 | } | |
1406 | ||
a061fc8d CM |
1407 | memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, |
1408 | sizeof(root->fs_info->super_copy)); | |
ccd467d6 | 1409 | |
f9295749 | 1410 | trans->transaction->blocked = 0; |
b7ec40d7 | 1411 | |
f9295749 | 1412 | wake_up(&root->fs_info->transaction_wait); |
e6dcd2dc | 1413 | |
78fae27e | 1414 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b CM |
1415 | ret = btrfs_write_and_wait_transaction(trans, root); |
1416 | BUG_ON(ret); | |
a512bbf8 | 1417 | write_ctree_super(trans, root, 0); |
4313b399 | 1418 | |
e02119d5 CM |
1419 | /* |
1420 | * the super is written, we can safely allow the tree-loggers | |
1421 | * to go about their business | |
1422 | */ | |
1423 | mutex_unlock(&root->fs_info->tree_log_mutex); | |
1424 | ||
11833d66 | 1425 | btrfs_finish_extent_commit(trans, root); |
4313b399 | 1426 | |
1a40e23b ZY |
1427 | mutex_lock(&root->fs_info->trans_mutex); |
1428 | ||
2c90e5d6 | 1429 | cur_trans->commit_done = 1; |
b7ec40d7 | 1430 | |
15ee9bc7 | 1431 | root->fs_info->last_trans_committed = cur_trans->transid; |
817d52f8 | 1432 | |
2c90e5d6 | 1433 | wake_up(&cur_trans->commit_wait); |
3de4586c | 1434 | |
13c5a93e | 1435 | list_del_init(&cur_trans->list); |
78fae27e | 1436 | put_transaction(cur_trans); |
79154b1b | 1437 | put_transaction(cur_trans); |
58176a96 | 1438 | |
1abe9b8a | 1439 | trace_btrfs_transaction_commit(root); |
1440 | ||
78fae27e | 1441 | mutex_unlock(&root->fs_info->trans_mutex); |
3de4586c | 1442 | |
9ed74f2d JB |
1443 | if (current->journal_info == trans) |
1444 | current->journal_info = NULL; | |
1445 | ||
2c90e5d6 | 1446 | kmem_cache_free(btrfs_trans_handle_cachep, trans); |
24bbcf04 YZ |
1447 | |
1448 | if (current != root->fs_info->transaction_kthread) | |
1449 | btrfs_run_delayed_iputs(root); | |
1450 | ||
79154b1b CM |
1451 | return ret; |
1452 | } | |
1453 | ||
d352ac68 CM |
1454 | /* |
1455 | * interface function to delete all the snapshots we have scheduled for deletion | |
1456 | */ | |
e9d0b13b CM |
1457 | int btrfs_clean_old_snapshots(struct btrfs_root *root) |
1458 | { | |
5d4f98a2 YZ |
1459 | LIST_HEAD(list); |
1460 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1461 | ||
1462 | mutex_lock(&fs_info->trans_mutex); | |
1463 | list_splice_init(&fs_info->dead_roots, &list); | |
1464 | mutex_unlock(&fs_info->trans_mutex); | |
e9d0b13b | 1465 | |
5d4f98a2 YZ |
1466 | while (!list_empty(&list)) { |
1467 | root = list_entry(list.next, struct btrfs_root, root_list); | |
76dda93c YZ |
1468 | list_del(&root->root_list); |
1469 | ||
16cdcec7 MX |
1470 | btrfs_kill_all_delayed_nodes(root); |
1471 | ||
76dda93c YZ |
1472 | if (btrfs_header_backref_rev(root->node) < |
1473 | BTRFS_MIXED_BACKREF_REV) | |
3fd0a558 | 1474 | btrfs_drop_snapshot(root, NULL, 0); |
76dda93c | 1475 | else |
3fd0a558 | 1476 | btrfs_drop_snapshot(root, NULL, 1); |
e9d0b13b CM |
1477 | } |
1478 | return 0; | |
1479 | } |