Commit | Line | Data |
---|---|---|
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, |
f993c883 | 83 | root->fs_info->btree_inode->i_mapping); |
48ec2cf8 CM |
84 | spin_lock(&root->fs_info->new_trans_lock); |
85 | root->fs_info->running_transaction = cur_trans; | |
86 | spin_unlock(&root->fs_info->new_trans_lock); | |
15ee9bc7 | 87 | } else { |
13c5a93e | 88 | atomic_inc(&cur_trans->num_writers); |
15ee9bc7 | 89 | cur_trans->num_joined++; |
79154b1b | 90 | } |
15ee9bc7 | 91 | |
79154b1b CM |
92 | return 0; |
93 | } | |
94 | ||
d352ac68 | 95 | /* |
d397712b CM |
96 | * this does all the record keeping required to make sure that a reference |
97 | * counted root is properly recorded in a given transaction. This is required | |
98 | * to make sure the old root from before we joined the transaction is deleted | |
99 | * when the transaction commits | |
d352ac68 | 100 | */ |
5d4f98a2 YZ |
101 | static noinline int record_root_in_trans(struct btrfs_trans_handle *trans, |
102 | struct btrfs_root *root) | |
6702ed49 | 103 | { |
5d4f98a2 | 104 | if (root->ref_cows && root->last_trans < trans->transid) { |
6702ed49 | 105 | WARN_ON(root == root->fs_info->extent_root); |
5d4f98a2 YZ |
106 | WARN_ON(root->commit_root != root->node); |
107 | ||
108 | radix_tree_tag_set(&root->fs_info->fs_roots_radix, | |
109 | (unsigned long)root->root_key.objectid, | |
110 | BTRFS_ROOT_TRANS_TAG); | |
111 | root->last_trans = trans->transid; | |
112 | btrfs_init_reloc_root(trans, root); | |
113 | } | |
114 | return 0; | |
115 | } | |
bcc63abb | 116 | |
5d4f98a2 YZ |
117 | int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, |
118 | struct btrfs_root *root) | |
119 | { | |
120 | if (!root->ref_cows) | |
121 | return 0; | |
bcc63abb | 122 | |
5d4f98a2 YZ |
123 | mutex_lock(&root->fs_info->trans_mutex); |
124 | if (root->last_trans == trans->transid) { | |
125 | mutex_unlock(&root->fs_info->trans_mutex); | |
126 | return 0; | |
6702ed49 | 127 | } |
5d4f98a2 YZ |
128 | |
129 | record_root_in_trans(trans, root); | |
130 | mutex_unlock(&root->fs_info->trans_mutex); | |
6702ed49 CM |
131 | return 0; |
132 | } | |
133 | ||
d352ac68 CM |
134 | /* wait for commit against the current transaction to become unblocked |
135 | * when this is done, it is safe to start a new transaction, but the current | |
136 | * transaction might not be fully on disk. | |
137 | */ | |
37d1aeee | 138 | static void wait_current_trans(struct btrfs_root *root) |
79154b1b | 139 | { |
f9295749 | 140 | struct btrfs_transaction *cur_trans; |
79154b1b | 141 | |
f9295749 | 142 | cur_trans = root->fs_info->running_transaction; |
37d1aeee | 143 | if (cur_trans && cur_trans->blocked) { |
f9295749 | 144 | DEFINE_WAIT(wait); |
13c5a93e | 145 | atomic_inc(&cur_trans->use_count); |
d397712b | 146 | while (1) { |
f9295749 CM |
147 | prepare_to_wait(&root->fs_info->transaction_wait, &wait, |
148 | TASK_UNINTERRUPTIBLE); | |
471fa17d | 149 | if (!cur_trans->blocked) |
f9295749 | 150 | break; |
471fa17d ZL |
151 | mutex_unlock(&root->fs_info->trans_mutex); |
152 | schedule(); | |
153 | mutex_lock(&root->fs_info->trans_mutex); | |
f9295749 | 154 | } |
471fa17d | 155 | finish_wait(&root->fs_info->transaction_wait, &wait); |
f9295749 CM |
156 | put_transaction(cur_trans); |
157 | } | |
37d1aeee CM |
158 | } |
159 | ||
249ac1e5 JB |
160 | enum btrfs_trans_type { |
161 | TRANS_START, | |
162 | TRANS_JOIN, | |
163 | TRANS_USERSPACE, | |
0af3d00b | 164 | TRANS_JOIN_NOLOCK, |
249ac1e5 JB |
165 | }; |
166 | ||
a22285a6 YZ |
167 | static int may_wait_transaction(struct btrfs_root *root, int type) |
168 | { | |
169 | if (!root->fs_info->log_root_recovering && | |
170 | ((type == TRANS_START && !root->fs_info->open_ioctl_trans) || | |
171 | type == TRANS_USERSPACE)) | |
172 | return 1; | |
173 | return 0; | |
174 | } | |
175 | ||
e02119d5 | 176 | static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, |
a22285a6 | 177 | u64 num_items, int type) |
37d1aeee | 178 | { |
a22285a6 YZ |
179 | struct btrfs_trans_handle *h; |
180 | struct btrfs_transaction *cur_trans; | |
06d5a589 | 181 | int retries = 0; |
37d1aeee | 182 | int ret; |
acce952b | 183 | |
184 | if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) | |
185 | return ERR_PTR(-EROFS); | |
a22285a6 YZ |
186 | again: |
187 | h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); | |
188 | if (!h) | |
189 | return ERR_PTR(-ENOMEM); | |
37d1aeee | 190 | |
0af3d00b JB |
191 | if (type != TRANS_JOIN_NOLOCK) |
192 | mutex_lock(&root->fs_info->trans_mutex); | |
a22285a6 | 193 | if (may_wait_transaction(root, type)) |
37d1aeee | 194 | wait_current_trans(root); |
a22285a6 | 195 | |
79154b1b | 196 | ret = join_transaction(root); |
db5b493a | 197 | if (ret < 0) { |
6e8df2ae | 198 | kmem_cache_free(btrfs_trans_handle_cachep, h); |
db5b493a TI |
199 | if (type != TRANS_JOIN_NOLOCK) |
200 | mutex_unlock(&root->fs_info->trans_mutex); | |
201 | return ERR_PTR(ret); | |
202 | } | |
0f7d52f4 | 203 | |
a22285a6 | 204 | cur_trans = root->fs_info->running_transaction; |
13c5a93e | 205 | atomic_inc(&cur_trans->use_count); |
0af3d00b JB |
206 | if (type != TRANS_JOIN_NOLOCK) |
207 | mutex_unlock(&root->fs_info->trans_mutex); | |
a22285a6 YZ |
208 | |
209 | h->transid = cur_trans->transid; | |
210 | h->transaction = cur_trans; | |
79154b1b | 211 | h->blocks_used = 0; |
d2fb3437 | 212 | h->block_group = 0; |
a22285a6 | 213 | h->bytes_reserved = 0; |
56bec294 | 214 | h->delayed_ref_updates = 0; |
f0486c68 | 215 | h->block_rsv = NULL; |
b7ec40d7 | 216 | |
a22285a6 YZ |
217 | smp_mb(); |
218 | if (cur_trans->blocked && may_wait_transaction(root, type)) { | |
219 | btrfs_commit_transaction(h, root); | |
220 | goto again; | |
221 | } | |
222 | ||
223 | if (num_items > 0) { | |
8bb8ab2e | 224 | ret = btrfs_trans_reserve_metadata(h, root, num_items); |
06d5a589 JB |
225 | if (ret == -EAGAIN && !retries) { |
226 | retries++; | |
a22285a6 YZ |
227 | btrfs_commit_transaction(h, root); |
228 | goto again; | |
06d5a589 JB |
229 | } else if (ret == -EAGAIN) { |
230 | /* | |
231 | * We have already retried and got EAGAIN, so really we | |
232 | * don't have space, so set ret to -ENOSPC. | |
233 | */ | |
234 | ret = -ENOSPC; | |
a22285a6 | 235 | } |
06d5a589 | 236 | |
a22285a6 YZ |
237 | if (ret < 0) { |
238 | btrfs_end_transaction(h, root); | |
239 | return ERR_PTR(ret); | |
240 | } | |
241 | } | |
9ed74f2d | 242 | |
0af3d00b JB |
243 | if (type != TRANS_JOIN_NOLOCK) |
244 | mutex_lock(&root->fs_info->trans_mutex); | |
5d4f98a2 | 245 | record_root_in_trans(h, root); |
0af3d00b JB |
246 | if (type != TRANS_JOIN_NOLOCK) |
247 | mutex_unlock(&root->fs_info->trans_mutex); | |
a22285a6 YZ |
248 | |
249 | if (!current->journal_info && type != TRANS_USERSPACE) | |
250 | current->journal_info = h; | |
79154b1b CM |
251 | return h; |
252 | } | |
253 | ||
f9295749 | 254 | struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, |
a22285a6 | 255 | int num_items) |
f9295749 | 256 | { |
a22285a6 | 257 | return start_transaction(root, num_items, TRANS_START); |
f9295749 CM |
258 | } |
259 | struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, | |
260 | int num_blocks) | |
261 | { | |
a22285a6 | 262 | return start_transaction(root, 0, TRANS_JOIN); |
f9295749 CM |
263 | } |
264 | ||
0af3d00b JB |
265 | struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root, |
266 | int num_blocks) | |
267 | { | |
268 | return start_transaction(root, 0, TRANS_JOIN_NOLOCK); | |
269 | } | |
270 | ||
9ca9ee09 SW |
271 | struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r, |
272 | int num_blocks) | |
273 | { | |
a22285a6 | 274 | return start_transaction(r, 0, TRANS_USERSPACE); |
9ca9ee09 SW |
275 | } |
276 | ||
d352ac68 | 277 | /* wait for a transaction commit to be fully complete */ |
89ce8a63 CM |
278 | static noinline int wait_for_commit(struct btrfs_root *root, |
279 | struct btrfs_transaction *commit) | |
280 | { | |
281 | DEFINE_WAIT(wait); | |
282 | mutex_lock(&root->fs_info->trans_mutex); | |
d397712b | 283 | while (!commit->commit_done) { |
89ce8a63 CM |
284 | prepare_to_wait(&commit->commit_wait, &wait, |
285 | TASK_UNINTERRUPTIBLE); | |
286 | if (commit->commit_done) | |
287 | break; | |
288 | mutex_unlock(&root->fs_info->trans_mutex); | |
289 | schedule(); | |
290 | mutex_lock(&root->fs_info->trans_mutex); | |
291 | } | |
292 | mutex_unlock(&root->fs_info->trans_mutex); | |
293 | finish_wait(&commit->commit_wait, &wait); | |
294 | return 0; | |
295 | } | |
296 | ||
46204592 SW |
297 | int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid) |
298 | { | |
299 | struct btrfs_transaction *cur_trans = NULL, *t; | |
300 | int ret; | |
301 | ||
302 | mutex_lock(&root->fs_info->trans_mutex); | |
303 | ||
304 | ret = 0; | |
305 | if (transid) { | |
306 | if (transid <= root->fs_info->last_trans_committed) | |
307 | goto out_unlock; | |
308 | ||
309 | /* find specified transaction */ | |
310 | list_for_each_entry(t, &root->fs_info->trans_list, list) { | |
311 | if (t->transid == transid) { | |
312 | cur_trans = t; | |
313 | break; | |
314 | } | |
315 | if (t->transid > transid) | |
316 | break; | |
317 | } | |
318 | ret = -EINVAL; | |
319 | if (!cur_trans) | |
320 | goto out_unlock; /* bad transid */ | |
321 | } else { | |
322 | /* find newest transaction that is committing | committed */ | |
323 | list_for_each_entry_reverse(t, &root->fs_info->trans_list, | |
324 | list) { | |
325 | if (t->in_commit) { | |
326 | if (t->commit_done) | |
327 | goto out_unlock; | |
328 | cur_trans = t; | |
329 | break; | |
330 | } | |
331 | } | |
332 | if (!cur_trans) | |
333 | goto out_unlock; /* nothing committing|committed */ | |
334 | } | |
335 | ||
13c5a93e | 336 | atomic_inc(&cur_trans->use_count); |
46204592 SW |
337 | mutex_unlock(&root->fs_info->trans_mutex); |
338 | ||
339 | wait_for_commit(root, cur_trans); | |
340 | ||
341 | mutex_lock(&root->fs_info->trans_mutex); | |
342 | put_transaction(cur_trans); | |
343 | ret = 0; | |
344 | out_unlock: | |
345 | mutex_unlock(&root->fs_info->trans_mutex); | |
346 | return ret; | |
347 | } | |
348 | ||
5d4f98a2 | 349 | #if 0 |
d352ac68 | 350 | /* |
d397712b CM |
351 | * rate limit against the drop_snapshot code. This helps to slow down new |
352 | * operations if the drop_snapshot code isn't able to keep up. | |
d352ac68 | 353 | */ |
37d1aeee | 354 | static void throttle_on_drops(struct btrfs_root *root) |
ab78c84d CM |
355 | { |
356 | struct btrfs_fs_info *info = root->fs_info; | |
2dd3e67b | 357 | int harder_count = 0; |
ab78c84d | 358 | |
2dd3e67b | 359 | harder: |
ab78c84d CM |
360 | if (atomic_read(&info->throttles)) { |
361 | DEFINE_WAIT(wait); | |
362 | int thr; | |
ab78c84d CM |
363 | thr = atomic_read(&info->throttle_gen); |
364 | ||
365 | do { | |
366 | prepare_to_wait(&info->transaction_throttle, | |
367 | &wait, TASK_UNINTERRUPTIBLE); | |
368 | if (!atomic_read(&info->throttles)) { | |
369 | finish_wait(&info->transaction_throttle, &wait); | |
370 | break; | |
371 | } | |
372 | schedule(); | |
373 | finish_wait(&info->transaction_throttle, &wait); | |
374 | } while (thr == atomic_read(&info->throttle_gen)); | |
2dd3e67b CM |
375 | harder_count++; |
376 | ||
377 | if (root->fs_info->total_ref_cache_size > 1 * 1024 * 1024 && | |
378 | harder_count < 2) | |
379 | goto harder; | |
380 | ||
381 | if (root->fs_info->total_ref_cache_size > 5 * 1024 * 1024 && | |
382 | harder_count < 10) | |
383 | goto harder; | |
384 | ||
385 | if (root->fs_info->total_ref_cache_size > 10 * 1024 * 1024 && | |
386 | harder_count < 20) | |
387 | goto harder; | |
ab78c84d CM |
388 | } |
389 | } | |
5d4f98a2 | 390 | #endif |
ab78c84d | 391 | |
37d1aeee CM |
392 | void btrfs_throttle(struct btrfs_root *root) |
393 | { | |
394 | mutex_lock(&root->fs_info->trans_mutex); | |
9ca9ee09 SW |
395 | if (!root->fs_info->open_ioctl_trans) |
396 | wait_current_trans(root); | |
37d1aeee | 397 | mutex_unlock(&root->fs_info->trans_mutex); |
37d1aeee CM |
398 | } |
399 | ||
8929ecfa YZ |
400 | static int should_end_transaction(struct btrfs_trans_handle *trans, |
401 | struct btrfs_root *root) | |
402 | { | |
403 | int ret; | |
404 | ret = btrfs_block_rsv_check(trans, root, | |
405 | &root->fs_info->global_block_rsv, 0, 5); | |
406 | return ret ? 1 : 0; | |
407 | } | |
408 | ||
409 | int btrfs_should_end_transaction(struct btrfs_trans_handle *trans, | |
410 | struct btrfs_root *root) | |
411 | { | |
412 | struct btrfs_transaction *cur_trans = trans->transaction; | |
413 | int updates; | |
414 | ||
415 | if (cur_trans->blocked || cur_trans->delayed_refs.flushing) | |
416 | return 1; | |
417 | ||
418 | updates = trans->delayed_ref_updates; | |
419 | trans->delayed_ref_updates = 0; | |
420 | if (updates) | |
421 | btrfs_run_delayed_refs(trans, root, updates); | |
422 | ||
423 | return should_end_transaction(trans, root); | |
424 | } | |
425 | ||
89ce8a63 | 426 | static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, |
0af3d00b | 427 | struct btrfs_root *root, int throttle, int lock) |
79154b1b | 428 | { |
8929ecfa | 429 | struct btrfs_transaction *cur_trans = trans->transaction; |
ab78c84d | 430 | struct btrfs_fs_info *info = root->fs_info; |
c3e69d58 CM |
431 | int count = 0; |
432 | ||
433 | while (count < 4) { | |
434 | unsigned long cur = trans->delayed_ref_updates; | |
435 | trans->delayed_ref_updates = 0; | |
436 | if (cur && | |
437 | trans->transaction->delayed_refs.num_heads_ready > 64) { | |
438 | trans->delayed_ref_updates = 0; | |
b7ec40d7 CM |
439 | |
440 | /* | |
441 | * do a full flush if the transaction is trying | |
442 | * to close | |
443 | */ | |
444 | if (trans->transaction->delayed_refs.flushing) | |
445 | cur = 0; | |
c3e69d58 CM |
446 | btrfs_run_delayed_refs(trans, root, cur); |
447 | } else { | |
448 | break; | |
449 | } | |
450 | count++; | |
56bec294 CM |
451 | } |
452 | ||
a22285a6 YZ |
453 | btrfs_trans_release_metadata(trans, root); |
454 | ||
0af3d00b | 455 | if (lock && !root->fs_info->open_ioctl_trans && |
8929ecfa YZ |
456 | should_end_transaction(trans, root)) |
457 | trans->transaction->blocked = 1; | |
458 | ||
0af3d00b | 459 | if (lock && cur_trans->blocked && !cur_trans->in_commit) { |
8929ecfa YZ |
460 | if (throttle) |
461 | return btrfs_commit_transaction(trans, root); | |
462 | else | |
463 | wake_up_process(info->transaction_kthread); | |
464 | } | |
465 | ||
8929ecfa | 466 | WARN_ON(cur_trans != info->running_transaction); |
13c5a93e JB |
467 | WARN_ON(atomic_read(&cur_trans->num_writers) < 1); |
468 | atomic_dec(&cur_trans->num_writers); | |
89ce8a63 | 469 | |
99d16cbc | 470 | smp_mb(); |
79154b1b CM |
471 | if (waitqueue_active(&cur_trans->writer_wait)) |
472 | wake_up(&cur_trans->writer_wait); | |
79154b1b | 473 | put_transaction(cur_trans); |
9ed74f2d JB |
474 | |
475 | if (current->journal_info == trans) | |
476 | current->journal_info = NULL; | |
d6025579 | 477 | memset(trans, 0, sizeof(*trans)); |
2c90e5d6 | 478 | kmem_cache_free(btrfs_trans_handle_cachep, trans); |
ab78c84d | 479 | |
24bbcf04 YZ |
480 | if (throttle) |
481 | btrfs_run_delayed_iputs(root); | |
482 | ||
79154b1b CM |
483 | return 0; |
484 | } | |
485 | ||
89ce8a63 CM |
486 | int btrfs_end_transaction(struct btrfs_trans_handle *trans, |
487 | struct btrfs_root *root) | |
488 | { | |
0af3d00b | 489 | return __btrfs_end_transaction(trans, root, 0, 1); |
89ce8a63 CM |
490 | } |
491 | ||
492 | int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, | |
493 | struct btrfs_root *root) | |
494 | { | |
0af3d00b JB |
495 | return __btrfs_end_transaction(trans, root, 1, 1); |
496 | } | |
497 | ||
498 | int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, | |
499 | struct btrfs_root *root) | |
500 | { | |
501 | return __btrfs_end_transaction(trans, root, 0, 0); | |
89ce8a63 CM |
502 | } |
503 | ||
d352ac68 CM |
504 | /* |
505 | * when btree blocks are allocated, they have some corresponding bits set for | |
506 | * them in one of two extent_io trees. This is used to make sure all of | |
690587d1 | 507 | * those extents are sent to disk but does not wait on them |
d352ac68 | 508 | */ |
690587d1 | 509 | int btrfs_write_marked_extents(struct btrfs_root *root, |
8cef4e16 | 510 | struct extent_io_tree *dirty_pages, int mark) |
79154b1b | 511 | { |
7c4452b9 | 512 | int ret; |
777e6bd7 | 513 | int err = 0; |
7c4452b9 CM |
514 | int werr = 0; |
515 | struct page *page; | |
7c4452b9 | 516 | struct inode *btree_inode = root->fs_info->btree_inode; |
777e6bd7 | 517 | u64 start = 0; |
5f39d397 CM |
518 | u64 end; |
519 | unsigned long index; | |
7c4452b9 | 520 | |
d397712b | 521 | while (1) { |
777e6bd7 | 522 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
8cef4e16 | 523 | mark); |
5f39d397 | 524 | if (ret) |
7c4452b9 | 525 | break; |
d397712b | 526 | while (start <= end) { |
777e6bd7 CM |
527 | cond_resched(); |
528 | ||
5f39d397 | 529 | index = start >> PAGE_CACHE_SHIFT; |
35ebb934 | 530 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; |
4bef0848 | 531 | page = find_get_page(btree_inode->i_mapping, index); |
7c4452b9 CM |
532 | if (!page) |
533 | continue; | |
4bef0848 CM |
534 | |
535 | btree_lock_page_hook(page); | |
536 | if (!page->mapping) { | |
537 | unlock_page(page); | |
538 | page_cache_release(page); | |
539 | continue; | |
540 | } | |
541 | ||
6702ed49 CM |
542 | if (PageWriteback(page)) { |
543 | if (PageDirty(page)) | |
544 | wait_on_page_writeback(page); | |
545 | else { | |
546 | unlock_page(page); | |
547 | page_cache_release(page); | |
548 | continue; | |
549 | } | |
550 | } | |
7c4452b9 CM |
551 | err = write_one_page(page, 0); |
552 | if (err) | |
553 | werr = err; | |
554 | page_cache_release(page); | |
555 | } | |
556 | } | |
690587d1 CM |
557 | if (err) |
558 | werr = err; | |
559 | return werr; | |
560 | } | |
561 | ||
562 | /* | |
563 | * when btree blocks are allocated, they have some corresponding bits set for | |
564 | * them in one of two extent_io trees. This is used to make sure all of | |
565 | * those extents are on disk for transaction or log commit. We wait | |
566 | * on all the pages and clear them from the dirty pages state tree | |
567 | */ | |
568 | int btrfs_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 569 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
570 | { |
571 | int ret; | |
572 | int err = 0; | |
573 | int werr = 0; | |
574 | struct page *page; | |
575 | struct inode *btree_inode = root->fs_info->btree_inode; | |
576 | u64 start = 0; | |
577 | u64 end; | |
578 | unsigned long index; | |
579 | ||
d397712b | 580 | while (1) { |
8cef4e16 YZ |
581 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
582 | mark); | |
777e6bd7 CM |
583 | if (ret) |
584 | break; | |
585 | ||
8cef4e16 | 586 | clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS); |
d397712b | 587 | while (start <= end) { |
777e6bd7 CM |
588 | index = start >> PAGE_CACHE_SHIFT; |
589 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; | |
590 | page = find_get_page(btree_inode->i_mapping, index); | |
591 | if (!page) | |
592 | continue; | |
593 | if (PageDirty(page)) { | |
4bef0848 CM |
594 | btree_lock_page_hook(page); |
595 | wait_on_page_writeback(page); | |
777e6bd7 CM |
596 | err = write_one_page(page, 0); |
597 | if (err) | |
598 | werr = err; | |
599 | } | |
105d931d | 600 | wait_on_page_writeback(page); |
777e6bd7 CM |
601 | page_cache_release(page); |
602 | cond_resched(); | |
603 | } | |
604 | } | |
7c4452b9 CM |
605 | if (err) |
606 | werr = err; | |
607 | return werr; | |
79154b1b CM |
608 | } |
609 | ||
690587d1 CM |
610 | /* |
611 | * when btree blocks are allocated, they have some corresponding bits set for | |
612 | * them in one of two extent_io trees. This is used to make sure all of | |
613 | * those extents are on disk for transaction or log commit | |
614 | */ | |
615 | int btrfs_write_and_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 616 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
617 | { |
618 | int ret; | |
619 | int ret2; | |
620 | ||
8cef4e16 YZ |
621 | ret = btrfs_write_marked_extents(root, dirty_pages, mark); |
622 | ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark); | |
690587d1 CM |
623 | return ret || ret2; |
624 | } | |
625 | ||
d0c803c4 CM |
626 | int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, |
627 | struct btrfs_root *root) | |
628 | { | |
629 | if (!trans || !trans->transaction) { | |
630 | struct inode *btree_inode; | |
631 | btree_inode = root->fs_info->btree_inode; | |
632 | return filemap_write_and_wait(btree_inode->i_mapping); | |
633 | } | |
634 | return btrfs_write_and_wait_marked_extents(root, | |
8cef4e16 YZ |
635 | &trans->transaction->dirty_pages, |
636 | EXTENT_DIRTY); | |
d0c803c4 CM |
637 | } |
638 | ||
d352ac68 CM |
639 | /* |
640 | * this is used to update the root pointer in the tree of tree roots. | |
641 | * | |
642 | * But, in the case of the extent allocation tree, updating the root | |
643 | * pointer may allocate blocks which may change the root of the extent | |
644 | * allocation tree. | |
645 | * | |
646 | * So, this loops and repeats and makes sure the cowonly root didn't | |
647 | * change while the root pointer was being updated in the metadata. | |
648 | */ | |
0b86a832 CM |
649 | static int update_cowonly_root(struct btrfs_trans_handle *trans, |
650 | struct btrfs_root *root) | |
79154b1b CM |
651 | { |
652 | int ret; | |
0b86a832 | 653 | u64 old_root_bytenr; |
86b9f2ec | 654 | u64 old_root_used; |
0b86a832 | 655 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
79154b1b | 656 | |
86b9f2ec | 657 | old_root_used = btrfs_root_used(&root->root_item); |
0b86a832 | 658 | btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 659 | |
d397712b | 660 | while (1) { |
0b86a832 | 661 | old_root_bytenr = btrfs_root_bytenr(&root->root_item); |
86b9f2ec YZ |
662 | if (old_root_bytenr == root->node->start && |
663 | old_root_used == btrfs_root_used(&root->root_item)) | |
79154b1b | 664 | break; |
87ef2bb4 | 665 | |
5d4f98a2 | 666 | btrfs_set_root_node(&root->root_item, root->node); |
79154b1b | 667 | ret = btrfs_update_root(trans, tree_root, |
0b86a832 CM |
668 | &root->root_key, |
669 | &root->root_item); | |
79154b1b | 670 | BUG_ON(ret); |
56bec294 | 671 | |
86b9f2ec | 672 | old_root_used = btrfs_root_used(&root->root_item); |
4a8c9a62 | 673 | ret = btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 674 | BUG_ON(ret); |
0b86a832 | 675 | } |
276e680d YZ |
676 | |
677 | if (root != root->fs_info->extent_root) | |
678 | switch_commit_root(root); | |
679 | ||
0b86a832 CM |
680 | return 0; |
681 | } | |
682 | ||
d352ac68 CM |
683 | /* |
684 | * update all the cowonly tree roots on disk | |
685 | */ | |
5d4f98a2 YZ |
686 | static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans, |
687 | struct btrfs_root *root) | |
0b86a832 CM |
688 | { |
689 | struct btrfs_fs_info *fs_info = root->fs_info; | |
690 | struct list_head *next; | |
84234f3a | 691 | struct extent_buffer *eb; |
56bec294 | 692 | int ret; |
84234f3a | 693 | |
56bec294 CM |
694 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
695 | BUG_ON(ret); | |
87ef2bb4 | 696 | |
84234f3a | 697 | eb = btrfs_lock_root_node(fs_info->tree_root); |
9fa8cfe7 | 698 | btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb); |
84234f3a YZ |
699 | btrfs_tree_unlock(eb); |
700 | free_extent_buffer(eb); | |
0b86a832 | 701 | |
56bec294 CM |
702 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
703 | BUG_ON(ret); | |
87ef2bb4 | 704 | |
d397712b | 705 | while (!list_empty(&fs_info->dirty_cowonly_roots)) { |
0b86a832 CM |
706 | next = fs_info->dirty_cowonly_roots.next; |
707 | list_del_init(next); | |
708 | root = list_entry(next, struct btrfs_root, dirty_list); | |
87ef2bb4 | 709 | |
0b86a832 | 710 | update_cowonly_root(trans, root); |
79154b1b | 711 | } |
276e680d YZ |
712 | |
713 | down_write(&fs_info->extent_commit_sem); | |
714 | switch_commit_root(fs_info->extent_root); | |
715 | up_write(&fs_info->extent_commit_sem); | |
716 | ||
79154b1b CM |
717 | return 0; |
718 | } | |
719 | ||
d352ac68 CM |
720 | /* |
721 | * dead roots are old snapshots that need to be deleted. This allocates | |
722 | * a dirty root struct and adds it into the list of dead roots that need to | |
723 | * be deleted | |
724 | */ | |
5d4f98a2 | 725 | int btrfs_add_dead_root(struct btrfs_root *root) |
5eda7b5e | 726 | { |
b48652c1 | 727 | mutex_lock(&root->fs_info->trans_mutex); |
5d4f98a2 | 728 | list_add(&root->root_list, &root->fs_info->dead_roots); |
b48652c1 | 729 | mutex_unlock(&root->fs_info->trans_mutex); |
5eda7b5e CM |
730 | return 0; |
731 | } | |
732 | ||
d352ac68 | 733 | /* |
5d4f98a2 | 734 | * update all the cowonly tree roots on disk |
d352ac68 | 735 | */ |
5d4f98a2 YZ |
736 | static noinline int commit_fs_roots(struct btrfs_trans_handle *trans, |
737 | struct btrfs_root *root) | |
0f7d52f4 | 738 | { |
0f7d52f4 | 739 | struct btrfs_root *gang[8]; |
5d4f98a2 | 740 | struct btrfs_fs_info *fs_info = root->fs_info; |
0f7d52f4 CM |
741 | int i; |
742 | int ret; | |
54aa1f4d CM |
743 | int err = 0; |
744 | ||
d397712b | 745 | while (1) { |
5d4f98a2 YZ |
746 | ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix, |
747 | (void **)gang, 0, | |
0f7d52f4 CM |
748 | ARRAY_SIZE(gang), |
749 | BTRFS_ROOT_TRANS_TAG); | |
750 | if (ret == 0) | |
751 | break; | |
752 | for (i = 0; i < ret; i++) { | |
753 | root = gang[i]; | |
5d4f98a2 YZ |
754 | radix_tree_tag_clear(&fs_info->fs_roots_radix, |
755 | (unsigned long)root->root_key.objectid, | |
756 | BTRFS_ROOT_TRANS_TAG); | |
31153d81 | 757 | |
e02119d5 | 758 | btrfs_free_log(trans, root); |
5d4f98a2 | 759 | btrfs_update_reloc_root(trans, root); |
d68fc57b | 760 | btrfs_orphan_commit_root(trans, root); |
bcc63abb | 761 | |
978d910d | 762 | if (root->commit_root != root->node) { |
817d52f8 | 763 | switch_commit_root(root); |
978d910d YZ |
764 | btrfs_set_root_node(&root->root_item, |
765 | root->node); | |
766 | } | |
5d4f98a2 | 767 | |
5d4f98a2 | 768 | err = btrfs_update_root(trans, fs_info->tree_root, |
0f7d52f4 CM |
769 | &root->root_key, |
770 | &root->root_item); | |
54aa1f4d CM |
771 | if (err) |
772 | break; | |
0f7d52f4 CM |
773 | } |
774 | } | |
54aa1f4d | 775 | return err; |
0f7d52f4 CM |
776 | } |
777 | ||
d352ac68 CM |
778 | /* |
779 | * defrag a given btree. If cacheonly == 1, this won't read from the disk, | |
780 | * otherwise every leaf in the btree is read and defragged. | |
781 | */ | |
e9d0b13b CM |
782 | int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) |
783 | { | |
784 | struct btrfs_fs_info *info = root->fs_info; | |
e9d0b13b | 785 | struct btrfs_trans_handle *trans; |
8929ecfa | 786 | int ret; |
d3c2fdcf | 787 | unsigned long nr; |
e9d0b13b | 788 | |
8929ecfa | 789 | if (xchg(&root->defrag_running, 1)) |
e9d0b13b | 790 | return 0; |
8929ecfa | 791 | |
6b80053d | 792 | while (1) { |
8929ecfa YZ |
793 | trans = btrfs_start_transaction(root, 0); |
794 | if (IS_ERR(trans)) | |
795 | return PTR_ERR(trans); | |
796 | ||
e9d0b13b | 797 | ret = btrfs_defrag_leaves(trans, root, cacheonly); |
8929ecfa | 798 | |
d3c2fdcf | 799 | nr = trans->blocks_used; |
e9d0b13b | 800 | btrfs_end_transaction(trans, root); |
d3c2fdcf | 801 | btrfs_btree_balance_dirty(info->tree_root, nr); |
e9d0b13b CM |
802 | cond_resched(); |
803 | ||
3f157a2f | 804 | if (root->fs_info->closing || ret != -EAGAIN) |
e9d0b13b CM |
805 | break; |
806 | } | |
807 | root->defrag_running = 0; | |
8929ecfa | 808 | return ret; |
e9d0b13b CM |
809 | } |
810 | ||
2c47e605 | 811 | #if 0 |
b7ec40d7 CM |
812 | /* |
813 | * when dropping snapshots, we generate a ton of delayed refs, and it makes | |
814 | * sense not to join the transaction while it is trying to flush the current | |
815 | * queue of delayed refs out. | |
816 | * | |
817 | * This is used by the drop snapshot code only | |
818 | */ | |
819 | static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info) | |
820 | { | |
821 | DEFINE_WAIT(wait); | |
822 | ||
823 | mutex_lock(&info->trans_mutex); | |
824 | while (info->running_transaction && | |
825 | info->running_transaction->delayed_refs.flushing) { | |
826 | prepare_to_wait(&info->transaction_wait, &wait, | |
827 | TASK_UNINTERRUPTIBLE); | |
828 | mutex_unlock(&info->trans_mutex); | |
59bc5c75 | 829 | |
b7ec40d7 | 830 | schedule(); |
59bc5c75 | 831 | |
b7ec40d7 CM |
832 | mutex_lock(&info->trans_mutex); |
833 | finish_wait(&info->transaction_wait, &wait); | |
834 | } | |
835 | mutex_unlock(&info->trans_mutex); | |
836 | return 0; | |
837 | } | |
838 | ||
d352ac68 CM |
839 | /* |
840 | * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on | |
841 | * all of them | |
842 | */ | |
5d4f98a2 | 843 | int btrfs_drop_dead_root(struct btrfs_root *root) |
0f7d52f4 | 844 | { |
0f7d52f4 | 845 | struct btrfs_trans_handle *trans; |
5d4f98a2 | 846 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
d3c2fdcf | 847 | unsigned long nr; |
5d4f98a2 | 848 | int ret; |
58176a96 | 849 | |
5d4f98a2 YZ |
850 | while (1) { |
851 | /* | |
852 | * we don't want to jump in and create a bunch of | |
853 | * delayed refs if the transaction is starting to close | |
854 | */ | |
855 | wait_transaction_pre_flush(tree_root->fs_info); | |
856 | trans = btrfs_start_transaction(tree_root, 1); | |
a2135011 | 857 | |
5d4f98a2 YZ |
858 | /* |
859 | * we've joined a transaction, make sure it isn't | |
860 | * closing right now | |
861 | */ | |
862 | if (trans->transaction->delayed_refs.flushing) { | |
863 | btrfs_end_transaction(trans, tree_root); | |
864 | continue; | |
9f3a7427 | 865 | } |
58176a96 | 866 | |
5d4f98a2 YZ |
867 | ret = btrfs_drop_snapshot(trans, root); |
868 | if (ret != -EAGAIN) | |
869 | break; | |
a2135011 | 870 | |
5d4f98a2 YZ |
871 | ret = btrfs_update_root(trans, tree_root, |
872 | &root->root_key, | |
873 | &root->root_item); | |
874 | if (ret) | |
54aa1f4d | 875 | break; |
bcc63abb | 876 | |
d3c2fdcf | 877 | nr = trans->blocks_used; |
0f7d52f4 CM |
878 | ret = btrfs_end_transaction(trans, tree_root); |
879 | BUG_ON(ret); | |
5eda7b5e | 880 | |
d3c2fdcf | 881 | btrfs_btree_balance_dirty(tree_root, nr); |
4dc11904 | 882 | cond_resched(); |
0f7d52f4 | 883 | } |
5d4f98a2 YZ |
884 | BUG_ON(ret); |
885 | ||
886 | ret = btrfs_del_root(trans, tree_root, &root->root_key); | |
887 | BUG_ON(ret); | |
888 | ||
889 | nr = trans->blocks_used; | |
890 | ret = btrfs_end_transaction(trans, tree_root); | |
891 | BUG_ON(ret); | |
892 | ||
893 | free_extent_buffer(root->node); | |
894 | free_extent_buffer(root->commit_root); | |
895 | kfree(root); | |
896 | ||
897 | btrfs_btree_balance_dirty(tree_root, nr); | |
54aa1f4d | 898 | return ret; |
0f7d52f4 | 899 | } |
2c47e605 | 900 | #endif |
0f7d52f4 | 901 | |
d352ac68 CM |
902 | /* |
903 | * new snapshots need to be created at a very specific time in the | |
904 | * transaction commit. This does the actual creation | |
905 | */ | |
80b6794d | 906 | static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, |
3063d29f CM |
907 | struct btrfs_fs_info *fs_info, |
908 | struct btrfs_pending_snapshot *pending) | |
909 | { | |
910 | struct btrfs_key key; | |
80b6794d | 911 | struct btrfs_root_item *new_root_item; |
3063d29f CM |
912 | struct btrfs_root *tree_root = fs_info->tree_root; |
913 | struct btrfs_root *root = pending->root; | |
6bdb72de SW |
914 | struct btrfs_root *parent_root; |
915 | struct inode *parent_inode; | |
6a912213 | 916 | struct dentry *parent; |
a22285a6 | 917 | struct dentry *dentry; |
3063d29f | 918 | struct extent_buffer *tmp; |
925baedd | 919 | struct extent_buffer *old; |
3063d29f | 920 | int ret; |
d68fc57b | 921 | u64 to_reserve = 0; |
6bdb72de | 922 | u64 index = 0; |
a22285a6 | 923 | u64 objectid; |
b83cc969 | 924 | u64 root_flags; |
3063d29f | 925 | |
80b6794d CM |
926 | new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); |
927 | if (!new_root_item) { | |
a22285a6 | 928 | pending->error = -ENOMEM; |
80b6794d CM |
929 | goto fail; |
930 | } | |
a22285a6 | 931 | |
3063d29f | 932 | ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); |
a22285a6 YZ |
933 | if (ret) { |
934 | pending->error = ret; | |
3063d29f | 935 | goto fail; |
a22285a6 | 936 | } |
3063d29f | 937 | |
3fd0a558 | 938 | btrfs_reloc_pre_snapshot(trans, pending, &to_reserve); |
d68fc57b YZ |
939 | btrfs_orphan_pre_snapshot(trans, pending, &to_reserve); |
940 | ||
941 | if (to_reserve > 0) { | |
942 | ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv, | |
8bb8ab2e | 943 | to_reserve); |
d68fc57b YZ |
944 | if (ret) { |
945 | pending->error = ret; | |
946 | goto fail; | |
947 | } | |
948 | } | |
949 | ||
3063d29f | 950 | key.objectid = objectid; |
a22285a6 YZ |
951 | key.offset = (u64)-1; |
952 | key.type = BTRFS_ROOT_ITEM_KEY; | |
3063d29f | 953 | |
a22285a6 | 954 | trans->block_rsv = &pending->block_rsv; |
3de4586c | 955 | |
a22285a6 | 956 | dentry = pending->dentry; |
6a912213 JB |
957 | parent = dget_parent(dentry); |
958 | parent_inode = parent->d_inode; | |
a22285a6 | 959 | parent_root = BTRFS_I(parent_inode)->root; |
6bdb72de | 960 | record_root_in_trans(trans, parent_root); |
a22285a6 | 961 | |
3063d29f CM |
962 | /* |
963 | * insert the directory item | |
964 | */ | |
3de4586c | 965 | ret = btrfs_set_inode_index(parent_inode, &index); |
6bdb72de | 966 | BUG_ON(ret); |
0660b5af | 967 | ret = btrfs_insert_dir_item(trans, parent_root, |
a22285a6 YZ |
968 | dentry->d_name.name, dentry->d_name.len, |
969 | parent_inode->i_ino, &key, | |
970 | BTRFS_FT_DIR, index); | |
6bdb72de | 971 | BUG_ON(ret); |
0660b5af | 972 | |
a22285a6 YZ |
973 | btrfs_i_size_write(parent_inode, parent_inode->i_size + |
974 | dentry->d_name.len * 2); | |
52c26179 YZ |
975 | ret = btrfs_update_inode(trans, parent_root, parent_inode); |
976 | BUG_ON(ret); | |
977 | ||
6bdb72de SW |
978 | record_root_in_trans(trans, root); |
979 | btrfs_set_root_last_snapshot(&root->root_item, trans->transid); | |
980 | memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); | |
08fe4db1 | 981 | btrfs_check_and_init_root_item(new_root_item); |
6bdb72de | 982 | |
b83cc969 LZ |
983 | root_flags = btrfs_root_flags(new_root_item); |
984 | if (pending->readonly) | |
985 | root_flags |= BTRFS_ROOT_SUBVOL_RDONLY; | |
986 | else | |
987 | root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY; | |
988 | btrfs_set_root_flags(new_root_item, root_flags); | |
989 | ||
6bdb72de SW |
990 | old = btrfs_lock_root_node(root); |
991 | btrfs_cow_block(trans, root, old, NULL, 0, &old); | |
992 | btrfs_set_lock_blocking(old); | |
993 | ||
994 | btrfs_copy_root(trans, root, old, &tmp, objectid); | |
995 | btrfs_tree_unlock(old); | |
996 | free_extent_buffer(old); | |
997 | ||
998 | btrfs_set_root_node(new_root_item, tmp); | |
a22285a6 YZ |
999 | /* record when the snapshot was created in key.offset */ |
1000 | key.offset = trans->transid; | |
1001 | ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); | |
6bdb72de SW |
1002 | btrfs_tree_unlock(tmp); |
1003 | free_extent_buffer(tmp); | |
a22285a6 | 1004 | BUG_ON(ret); |
6bdb72de | 1005 | |
a22285a6 YZ |
1006 | /* |
1007 | * insert root back/forward references | |
1008 | */ | |
1009 | ret = btrfs_add_root_ref(trans, tree_root, objectid, | |
0660b5af | 1010 | parent_root->root_key.objectid, |
a22285a6 YZ |
1011 | parent_inode->i_ino, index, |
1012 | dentry->d_name.name, dentry->d_name.len); | |
0660b5af | 1013 | BUG_ON(ret); |
6a912213 | 1014 | dput(parent); |
0660b5af | 1015 | |
a22285a6 YZ |
1016 | key.offset = (u64)-1; |
1017 | pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); | |
1018 | BUG_ON(IS_ERR(pending->snap)); | |
d68fc57b | 1019 | |
3fd0a558 | 1020 | btrfs_reloc_post_snapshot(trans, pending); |
d68fc57b | 1021 | btrfs_orphan_post_snapshot(trans, pending); |
3063d29f | 1022 | fail: |
6bdb72de | 1023 | kfree(new_root_item); |
a22285a6 YZ |
1024 | btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); |
1025 | return 0; | |
3063d29f CM |
1026 | } |
1027 | ||
d352ac68 CM |
1028 | /* |
1029 | * create all the snapshots we've scheduled for creation | |
1030 | */ | |
80b6794d CM |
1031 | static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, |
1032 | struct btrfs_fs_info *fs_info) | |
3de4586c CM |
1033 | { |
1034 | struct btrfs_pending_snapshot *pending; | |
1035 | struct list_head *head = &trans->transaction->pending_snapshots; | |
3de4586c CM |
1036 | int ret; |
1037 | ||
c6e30871 | 1038 | list_for_each_entry(pending, head, list) { |
3de4586c CM |
1039 | ret = create_pending_snapshot(trans, fs_info, pending); |
1040 | BUG_ON(ret); | |
1041 | } | |
1042 | return 0; | |
1043 | } | |
1044 | ||
5d4f98a2 YZ |
1045 | static void update_super_roots(struct btrfs_root *root) |
1046 | { | |
1047 | struct btrfs_root_item *root_item; | |
1048 | struct btrfs_super_block *super; | |
1049 | ||
1050 | super = &root->fs_info->super_copy; | |
1051 | ||
1052 | root_item = &root->fs_info->chunk_root->root_item; | |
1053 | super->chunk_root = root_item->bytenr; | |
1054 | super->chunk_root_generation = root_item->generation; | |
1055 | super->chunk_root_level = root_item->level; | |
1056 | ||
1057 | root_item = &root->fs_info->tree_root->root_item; | |
1058 | super->root = root_item->bytenr; | |
1059 | super->generation = root_item->generation; | |
1060 | super->root_level = root_item->level; | |
0af3d00b JB |
1061 | if (super->cache_generation != 0 || btrfs_test_opt(root, SPACE_CACHE)) |
1062 | super->cache_generation = root_item->generation; | |
5d4f98a2 YZ |
1063 | } |
1064 | ||
f36f3042 CM |
1065 | int btrfs_transaction_in_commit(struct btrfs_fs_info *info) |
1066 | { | |
1067 | int ret = 0; | |
1068 | spin_lock(&info->new_trans_lock); | |
1069 | if (info->running_transaction) | |
1070 | ret = info->running_transaction->in_commit; | |
1071 | spin_unlock(&info->new_trans_lock); | |
1072 | return ret; | |
1073 | } | |
1074 | ||
8929ecfa YZ |
1075 | int btrfs_transaction_blocked(struct btrfs_fs_info *info) |
1076 | { | |
1077 | int ret = 0; | |
1078 | spin_lock(&info->new_trans_lock); | |
1079 | if (info->running_transaction) | |
1080 | ret = info->running_transaction->blocked; | |
1081 | spin_unlock(&info->new_trans_lock); | |
1082 | return ret; | |
1083 | } | |
1084 | ||
bb9c12c9 SW |
1085 | /* |
1086 | * wait for the current transaction commit to start and block subsequent | |
1087 | * transaction joins | |
1088 | */ | |
1089 | static void wait_current_trans_commit_start(struct btrfs_root *root, | |
1090 | struct btrfs_transaction *trans) | |
1091 | { | |
1092 | DEFINE_WAIT(wait); | |
1093 | ||
1094 | if (trans->in_commit) | |
1095 | return; | |
1096 | ||
1097 | while (1) { | |
1098 | prepare_to_wait(&root->fs_info->transaction_blocked_wait, &wait, | |
1099 | TASK_UNINTERRUPTIBLE); | |
1100 | if (trans->in_commit) { | |
1101 | finish_wait(&root->fs_info->transaction_blocked_wait, | |
1102 | &wait); | |
1103 | break; | |
1104 | } | |
1105 | mutex_unlock(&root->fs_info->trans_mutex); | |
1106 | schedule(); | |
1107 | mutex_lock(&root->fs_info->trans_mutex); | |
1108 | finish_wait(&root->fs_info->transaction_blocked_wait, &wait); | |
1109 | } | |
1110 | } | |
1111 | ||
1112 | /* | |
1113 | * wait for the current transaction to start and then become unblocked. | |
1114 | * caller holds ref. | |
1115 | */ | |
1116 | static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root, | |
1117 | struct btrfs_transaction *trans) | |
1118 | { | |
1119 | DEFINE_WAIT(wait); | |
1120 | ||
1121 | if (trans->commit_done || (trans->in_commit && !trans->blocked)) | |
1122 | return; | |
1123 | ||
1124 | while (1) { | |
1125 | prepare_to_wait(&root->fs_info->transaction_wait, &wait, | |
1126 | TASK_UNINTERRUPTIBLE); | |
1127 | if (trans->commit_done || | |
1128 | (trans->in_commit && !trans->blocked)) { | |
1129 | finish_wait(&root->fs_info->transaction_wait, | |
1130 | &wait); | |
1131 | break; | |
1132 | } | |
1133 | mutex_unlock(&root->fs_info->trans_mutex); | |
1134 | schedule(); | |
1135 | mutex_lock(&root->fs_info->trans_mutex); | |
1136 | finish_wait(&root->fs_info->transaction_wait, | |
1137 | &wait); | |
1138 | } | |
1139 | } | |
1140 | ||
1141 | /* | |
1142 | * commit transactions asynchronously. once btrfs_commit_transaction_async | |
1143 | * returns, any subsequent transaction will not be allowed to join. | |
1144 | */ | |
1145 | struct btrfs_async_commit { | |
1146 | struct btrfs_trans_handle *newtrans; | |
1147 | struct btrfs_root *root; | |
1148 | struct delayed_work work; | |
1149 | }; | |
1150 | ||
1151 | static void do_async_commit(struct work_struct *work) | |
1152 | { | |
1153 | struct btrfs_async_commit *ac = | |
1154 | container_of(work, struct btrfs_async_commit, work.work); | |
1155 | ||
1156 | btrfs_commit_transaction(ac->newtrans, ac->root); | |
1157 | kfree(ac); | |
1158 | } | |
1159 | ||
1160 | int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans, | |
1161 | struct btrfs_root *root, | |
1162 | int wait_for_unblock) | |
1163 | { | |
1164 | struct btrfs_async_commit *ac; | |
1165 | struct btrfs_transaction *cur_trans; | |
1166 | ||
1167 | ac = kmalloc(sizeof(*ac), GFP_NOFS); | |
db5b493a TI |
1168 | if (!ac) |
1169 | return -ENOMEM; | |
bb9c12c9 SW |
1170 | |
1171 | INIT_DELAYED_WORK(&ac->work, do_async_commit); | |
1172 | ac->root = root; | |
1173 | ac->newtrans = btrfs_join_transaction(root, 0); | |
3612b495 TI |
1174 | if (IS_ERR(ac->newtrans)) { |
1175 | int err = PTR_ERR(ac->newtrans); | |
1176 | kfree(ac); | |
1177 | return err; | |
1178 | } | |
bb9c12c9 SW |
1179 | |
1180 | /* take transaction reference */ | |
1181 | mutex_lock(&root->fs_info->trans_mutex); | |
1182 | cur_trans = trans->transaction; | |
13c5a93e | 1183 | atomic_inc(&cur_trans->use_count); |
bb9c12c9 SW |
1184 | mutex_unlock(&root->fs_info->trans_mutex); |
1185 | ||
1186 | btrfs_end_transaction(trans, root); | |
1187 | schedule_delayed_work(&ac->work, 0); | |
1188 | ||
1189 | /* wait for transaction to start and unblock */ | |
1190 | mutex_lock(&root->fs_info->trans_mutex); | |
1191 | if (wait_for_unblock) | |
1192 | wait_current_trans_commit_start_and_unblock(root, cur_trans); | |
1193 | else | |
1194 | wait_current_trans_commit_start(root, cur_trans); | |
1195 | put_transaction(cur_trans); | |
1196 | mutex_unlock(&root->fs_info->trans_mutex); | |
1197 | ||
1198 | return 0; | |
1199 | } | |
1200 | ||
1201 | /* | |
1202 | * btrfs_transaction state sequence: | |
1203 | * in_commit = 0, blocked = 0 (initial) | |
1204 | * in_commit = 1, blocked = 1 | |
1205 | * blocked = 0 | |
1206 | * commit_done = 1 | |
1207 | */ | |
79154b1b CM |
1208 | int btrfs_commit_transaction(struct btrfs_trans_handle *trans, |
1209 | struct btrfs_root *root) | |
1210 | { | |
15ee9bc7 | 1211 | unsigned long joined = 0; |
79154b1b | 1212 | struct btrfs_transaction *cur_trans; |
8fd17795 | 1213 | struct btrfs_transaction *prev_trans = NULL; |
79154b1b | 1214 | DEFINE_WAIT(wait); |
15ee9bc7 | 1215 | int ret; |
89573b9c CM |
1216 | int should_grow = 0; |
1217 | unsigned long now = get_seconds(); | |
dccae999 | 1218 | int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT); |
79154b1b | 1219 | |
5a3f23d5 CM |
1220 | btrfs_run_ordered_operations(root, 0); |
1221 | ||
56bec294 CM |
1222 | /* make a pass through all the delayed refs we have so far |
1223 | * any runnings procs may add more while we are here | |
1224 | */ | |
1225 | ret = btrfs_run_delayed_refs(trans, root, 0); | |
1226 | BUG_ON(ret); | |
1227 | ||
a22285a6 YZ |
1228 | btrfs_trans_release_metadata(trans, root); |
1229 | ||
b7ec40d7 | 1230 | cur_trans = trans->transaction; |
56bec294 CM |
1231 | /* |
1232 | * set the flushing flag so procs in this transaction have to | |
1233 | * start sending their work down. | |
1234 | */ | |
b7ec40d7 | 1235 | cur_trans->delayed_refs.flushing = 1; |
56bec294 | 1236 | |
c3e69d58 | 1237 | ret = btrfs_run_delayed_refs(trans, root, 0); |
56bec294 CM |
1238 | BUG_ON(ret); |
1239 | ||
79154b1b | 1240 | mutex_lock(&root->fs_info->trans_mutex); |
b7ec40d7 | 1241 | if (cur_trans->in_commit) { |
13c5a93e | 1242 | atomic_inc(&cur_trans->use_count); |
ccd467d6 | 1243 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b | 1244 | btrfs_end_transaction(trans, root); |
ccd467d6 | 1245 | |
79154b1b CM |
1246 | ret = wait_for_commit(root, cur_trans); |
1247 | BUG_ON(ret); | |
15ee9bc7 JB |
1248 | |
1249 | mutex_lock(&root->fs_info->trans_mutex); | |
79154b1b | 1250 | put_transaction(cur_trans); |
15ee9bc7 JB |
1251 | mutex_unlock(&root->fs_info->trans_mutex); |
1252 | ||
79154b1b CM |
1253 | return 0; |
1254 | } | |
4313b399 | 1255 | |
2c90e5d6 | 1256 | trans->transaction->in_commit = 1; |
f9295749 | 1257 | trans->transaction->blocked = 1; |
bb9c12c9 SW |
1258 | wake_up(&root->fs_info->transaction_blocked_wait); |
1259 | ||
ccd467d6 CM |
1260 | if (cur_trans->list.prev != &root->fs_info->trans_list) { |
1261 | prev_trans = list_entry(cur_trans->list.prev, | |
1262 | struct btrfs_transaction, list); | |
1263 | if (!prev_trans->commit_done) { | |
13c5a93e | 1264 | atomic_inc(&prev_trans->use_count); |
ccd467d6 CM |
1265 | mutex_unlock(&root->fs_info->trans_mutex); |
1266 | ||
1267 | wait_for_commit(root, prev_trans); | |
ccd467d6 | 1268 | |
ccd467d6 | 1269 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1270 | put_transaction(prev_trans); |
ccd467d6 CM |
1271 | } |
1272 | } | |
15ee9bc7 | 1273 | |
89573b9c CM |
1274 | if (now < cur_trans->start_time || now - cur_trans->start_time < 1) |
1275 | should_grow = 1; | |
1276 | ||
15ee9bc7 | 1277 | do { |
7ea394f1 | 1278 | int snap_pending = 0; |
15ee9bc7 | 1279 | joined = cur_trans->num_joined; |
7ea394f1 YZ |
1280 | if (!list_empty(&trans->transaction->pending_snapshots)) |
1281 | snap_pending = 1; | |
1282 | ||
2c90e5d6 | 1283 | WARN_ON(cur_trans != trans->transaction); |
79154b1b | 1284 | mutex_unlock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1285 | |
0bdb1db2 | 1286 | if (flush_on_commit || snap_pending) { |
24bbcf04 YZ |
1287 | btrfs_start_delalloc_inodes(root, 1); |
1288 | ret = btrfs_wait_ordered_extents(root, 0, 1); | |
ebecd3d9 | 1289 | BUG_ON(ret); |
7ea394f1 YZ |
1290 | } |
1291 | ||
5a3f23d5 CM |
1292 | /* |
1293 | * rename don't use btrfs_join_transaction, so, once we | |
1294 | * set the transaction to blocked above, we aren't going | |
1295 | * to get any new ordered operations. We can safely run | |
1296 | * it here and no for sure that nothing new will be added | |
1297 | * to the list | |
1298 | */ | |
1299 | btrfs_run_ordered_operations(root, 1); | |
1300 | ||
ed3b3d31 CM |
1301 | prepare_to_wait(&cur_trans->writer_wait, &wait, |
1302 | TASK_UNINTERRUPTIBLE); | |
1303 | ||
89573b9c | 1304 | smp_mb(); |
13c5a93e | 1305 | if (atomic_read(&cur_trans->num_writers) > 1) |
99d16cbc SW |
1306 | schedule_timeout(MAX_SCHEDULE_TIMEOUT); |
1307 | else if (should_grow) | |
1308 | schedule_timeout(1); | |
15ee9bc7 | 1309 | |
79154b1b | 1310 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1311 | finish_wait(&cur_trans->writer_wait, &wait); |
13c5a93e | 1312 | } while (atomic_read(&cur_trans->num_writers) > 1 || |
89573b9c | 1313 | (should_grow && cur_trans->num_joined != joined)); |
15ee9bc7 | 1314 | |
3063d29f CM |
1315 | ret = create_pending_snapshots(trans, root->fs_info); |
1316 | BUG_ON(ret); | |
1317 | ||
56bec294 CM |
1318 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
1319 | BUG_ON(ret); | |
1320 | ||
2c90e5d6 | 1321 | WARN_ON(cur_trans != trans->transaction); |
dc17ff8f | 1322 | |
e02119d5 CM |
1323 | /* btrfs_commit_tree_roots is responsible for getting the |
1324 | * various roots consistent with each other. Every pointer | |
1325 | * in the tree of tree roots has to point to the most up to date | |
1326 | * root for every subvolume and other tree. So, we have to keep | |
1327 | * the tree logging code from jumping in and changing any | |
1328 | * of the trees. | |
1329 | * | |
1330 | * At this point in the commit, there can't be any tree-log | |
1331 | * writers, but a little lower down we drop the trans mutex | |
1332 | * and let new people in. By holding the tree_log_mutex | |
1333 | * from now until after the super is written, we avoid races | |
1334 | * with the tree-log code. | |
1335 | */ | |
1336 | mutex_lock(&root->fs_info->tree_log_mutex); | |
1337 | ||
5d4f98a2 | 1338 | ret = commit_fs_roots(trans, root); |
54aa1f4d CM |
1339 | BUG_ON(ret); |
1340 | ||
5d4f98a2 | 1341 | /* commit_fs_roots gets rid of all the tree log roots, it is now |
e02119d5 CM |
1342 | * safe to free the root of tree log roots |
1343 | */ | |
1344 | btrfs_free_log_root_tree(trans, root->fs_info); | |
1345 | ||
5d4f98a2 | 1346 | ret = commit_cowonly_roots(trans, root); |
79154b1b | 1347 | BUG_ON(ret); |
54aa1f4d | 1348 | |
11833d66 YZ |
1349 | btrfs_prepare_extent_commit(trans, root); |
1350 | ||
78fae27e | 1351 | cur_trans = root->fs_info->running_transaction; |
cee36a03 | 1352 | spin_lock(&root->fs_info->new_trans_lock); |
78fae27e | 1353 | root->fs_info->running_transaction = NULL; |
cee36a03 | 1354 | spin_unlock(&root->fs_info->new_trans_lock); |
5d4f98a2 YZ |
1355 | |
1356 | btrfs_set_root_node(&root->fs_info->tree_root->root_item, | |
1357 | root->fs_info->tree_root->node); | |
817d52f8 | 1358 | switch_commit_root(root->fs_info->tree_root); |
5d4f98a2 YZ |
1359 | |
1360 | btrfs_set_root_node(&root->fs_info->chunk_root->root_item, | |
1361 | root->fs_info->chunk_root->node); | |
817d52f8 | 1362 | switch_commit_root(root->fs_info->chunk_root); |
5d4f98a2 YZ |
1363 | |
1364 | update_super_roots(root); | |
e02119d5 CM |
1365 | |
1366 | if (!root->fs_info->log_root_recovering) { | |
1367 | btrfs_set_super_log_root(&root->fs_info->super_copy, 0); | |
1368 | btrfs_set_super_log_root_level(&root->fs_info->super_copy, 0); | |
1369 | } | |
1370 | ||
a061fc8d CM |
1371 | memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, |
1372 | sizeof(root->fs_info->super_copy)); | |
ccd467d6 | 1373 | |
f9295749 | 1374 | trans->transaction->blocked = 0; |
b7ec40d7 | 1375 | |
f9295749 | 1376 | wake_up(&root->fs_info->transaction_wait); |
e6dcd2dc | 1377 | |
78fae27e | 1378 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b CM |
1379 | ret = btrfs_write_and_wait_transaction(trans, root); |
1380 | BUG_ON(ret); | |
a512bbf8 | 1381 | write_ctree_super(trans, root, 0); |
4313b399 | 1382 | |
e02119d5 CM |
1383 | /* |
1384 | * the super is written, we can safely allow the tree-loggers | |
1385 | * to go about their business | |
1386 | */ | |
1387 | mutex_unlock(&root->fs_info->tree_log_mutex); | |
1388 | ||
11833d66 | 1389 | btrfs_finish_extent_commit(trans, root); |
4313b399 | 1390 | |
1a40e23b ZY |
1391 | mutex_lock(&root->fs_info->trans_mutex); |
1392 | ||
2c90e5d6 | 1393 | cur_trans->commit_done = 1; |
b7ec40d7 | 1394 | |
15ee9bc7 | 1395 | root->fs_info->last_trans_committed = cur_trans->transid; |
817d52f8 | 1396 | |
2c90e5d6 | 1397 | wake_up(&cur_trans->commit_wait); |
3de4586c | 1398 | |
13c5a93e | 1399 | list_del_init(&cur_trans->list); |
78fae27e | 1400 | put_transaction(cur_trans); |
79154b1b | 1401 | put_transaction(cur_trans); |
58176a96 | 1402 | |
1abe9b8a | 1403 | trace_btrfs_transaction_commit(root); |
1404 | ||
78fae27e | 1405 | mutex_unlock(&root->fs_info->trans_mutex); |
3de4586c | 1406 | |
9ed74f2d JB |
1407 | if (current->journal_info == trans) |
1408 | current->journal_info = NULL; | |
1409 | ||
2c90e5d6 | 1410 | kmem_cache_free(btrfs_trans_handle_cachep, trans); |
24bbcf04 YZ |
1411 | |
1412 | if (current != root->fs_info->transaction_kthread) | |
1413 | btrfs_run_delayed_iputs(root); | |
1414 | ||
79154b1b CM |
1415 | return ret; |
1416 | } | |
1417 | ||
d352ac68 CM |
1418 | /* |
1419 | * interface function to delete all the snapshots we have scheduled for deletion | |
1420 | */ | |
e9d0b13b CM |
1421 | int btrfs_clean_old_snapshots(struct btrfs_root *root) |
1422 | { | |
5d4f98a2 YZ |
1423 | LIST_HEAD(list); |
1424 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1425 | ||
1426 | mutex_lock(&fs_info->trans_mutex); | |
1427 | list_splice_init(&fs_info->dead_roots, &list); | |
1428 | mutex_unlock(&fs_info->trans_mutex); | |
e9d0b13b | 1429 | |
5d4f98a2 YZ |
1430 | while (!list_empty(&list)) { |
1431 | root = list_entry(list.next, struct btrfs_root, root_list); | |
76dda93c YZ |
1432 | list_del(&root->root_list); |
1433 | ||
1434 | if (btrfs_header_backref_rev(root->node) < | |
1435 | BTRFS_MIXED_BACKREF_REV) | |
3fd0a558 | 1436 | btrfs_drop_snapshot(root, NULL, 0); |
76dda93c | 1437 | else |
3fd0a558 | 1438 | btrfs_drop_snapshot(root, NULL, 1); |
e9d0b13b CM |
1439 | } |
1440 | return 0; | |
1441 | } |