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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 | { | |
0af3d00b | 490 | return __btrfs_end_transaction(trans, root, 0, 1); |
89ce8a63 CM |
491 | } |
492 | ||
493 | int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, | |
494 | struct btrfs_root *root) | |
495 | { | |
0af3d00b JB |
496 | return __btrfs_end_transaction(trans, root, 1, 1); |
497 | } | |
498 | ||
499 | int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, | |
500 | struct btrfs_root *root) | |
501 | { | |
502 | return __btrfs_end_transaction(trans, root, 0, 0); | |
89ce8a63 CM |
503 | } |
504 | ||
d352ac68 CM |
505 | /* |
506 | * when btree blocks are allocated, they have some corresponding bits set for | |
507 | * them in one of two extent_io trees. This is used to make sure all of | |
690587d1 | 508 | * those extents are sent to disk but does not wait on them |
d352ac68 | 509 | */ |
690587d1 | 510 | int btrfs_write_marked_extents(struct btrfs_root *root, |
8cef4e16 | 511 | struct extent_io_tree *dirty_pages, int mark) |
79154b1b | 512 | { |
7c4452b9 | 513 | int ret; |
777e6bd7 | 514 | int err = 0; |
7c4452b9 CM |
515 | int werr = 0; |
516 | struct page *page; | |
7c4452b9 | 517 | struct inode *btree_inode = root->fs_info->btree_inode; |
777e6bd7 | 518 | u64 start = 0; |
5f39d397 CM |
519 | u64 end; |
520 | unsigned long index; | |
7c4452b9 | 521 | |
d397712b | 522 | while (1) { |
777e6bd7 | 523 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
8cef4e16 | 524 | mark); |
5f39d397 | 525 | if (ret) |
7c4452b9 | 526 | break; |
d397712b | 527 | while (start <= end) { |
777e6bd7 CM |
528 | cond_resched(); |
529 | ||
5f39d397 | 530 | index = start >> PAGE_CACHE_SHIFT; |
35ebb934 | 531 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; |
4bef0848 | 532 | page = find_get_page(btree_inode->i_mapping, index); |
7c4452b9 CM |
533 | if (!page) |
534 | continue; | |
4bef0848 CM |
535 | |
536 | btree_lock_page_hook(page); | |
537 | if (!page->mapping) { | |
538 | unlock_page(page); | |
539 | page_cache_release(page); | |
540 | continue; | |
541 | } | |
542 | ||
6702ed49 CM |
543 | if (PageWriteback(page)) { |
544 | if (PageDirty(page)) | |
545 | wait_on_page_writeback(page); | |
546 | else { | |
547 | unlock_page(page); | |
548 | page_cache_release(page); | |
549 | continue; | |
550 | } | |
551 | } | |
7c4452b9 CM |
552 | err = write_one_page(page, 0); |
553 | if (err) | |
554 | werr = err; | |
555 | page_cache_release(page); | |
556 | } | |
557 | } | |
690587d1 CM |
558 | if (err) |
559 | werr = err; | |
560 | return werr; | |
561 | } | |
562 | ||
563 | /* | |
564 | * when btree blocks are allocated, they have some corresponding bits set for | |
565 | * them in one of two extent_io trees. This is used to make sure all of | |
566 | * those extents are on disk for transaction or log commit. We wait | |
567 | * on all the pages and clear them from the dirty pages state tree | |
568 | */ | |
569 | int btrfs_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 570 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
571 | { |
572 | int ret; | |
573 | int err = 0; | |
574 | int werr = 0; | |
575 | struct page *page; | |
576 | struct inode *btree_inode = root->fs_info->btree_inode; | |
577 | u64 start = 0; | |
578 | u64 end; | |
579 | unsigned long index; | |
580 | ||
d397712b | 581 | while (1) { |
8cef4e16 YZ |
582 | ret = find_first_extent_bit(dirty_pages, start, &start, &end, |
583 | mark); | |
777e6bd7 CM |
584 | if (ret) |
585 | break; | |
586 | ||
8cef4e16 | 587 | clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS); |
d397712b | 588 | while (start <= end) { |
777e6bd7 CM |
589 | index = start >> PAGE_CACHE_SHIFT; |
590 | start = (u64)(index + 1) << PAGE_CACHE_SHIFT; | |
591 | page = find_get_page(btree_inode->i_mapping, index); | |
592 | if (!page) | |
593 | continue; | |
594 | if (PageDirty(page)) { | |
4bef0848 CM |
595 | btree_lock_page_hook(page); |
596 | wait_on_page_writeback(page); | |
777e6bd7 CM |
597 | err = write_one_page(page, 0); |
598 | if (err) | |
599 | werr = err; | |
600 | } | |
105d931d | 601 | wait_on_page_writeback(page); |
777e6bd7 CM |
602 | page_cache_release(page); |
603 | cond_resched(); | |
604 | } | |
605 | } | |
7c4452b9 CM |
606 | if (err) |
607 | werr = err; | |
608 | return werr; | |
79154b1b CM |
609 | } |
610 | ||
690587d1 CM |
611 | /* |
612 | * when btree blocks are allocated, they have some corresponding bits set for | |
613 | * them in one of two extent_io trees. This is used to make sure all of | |
614 | * those extents are on disk for transaction or log commit | |
615 | */ | |
616 | int btrfs_write_and_wait_marked_extents(struct btrfs_root *root, | |
8cef4e16 | 617 | struct extent_io_tree *dirty_pages, int mark) |
690587d1 CM |
618 | { |
619 | int ret; | |
620 | int ret2; | |
621 | ||
8cef4e16 YZ |
622 | ret = btrfs_write_marked_extents(root, dirty_pages, mark); |
623 | ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark); | |
690587d1 CM |
624 | return ret || ret2; |
625 | } | |
626 | ||
d0c803c4 CM |
627 | int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, |
628 | struct btrfs_root *root) | |
629 | { | |
630 | if (!trans || !trans->transaction) { | |
631 | struct inode *btree_inode; | |
632 | btree_inode = root->fs_info->btree_inode; | |
633 | return filemap_write_and_wait(btree_inode->i_mapping); | |
634 | } | |
635 | return btrfs_write_and_wait_marked_extents(root, | |
8cef4e16 YZ |
636 | &trans->transaction->dirty_pages, |
637 | EXTENT_DIRTY); | |
d0c803c4 CM |
638 | } |
639 | ||
d352ac68 CM |
640 | /* |
641 | * this is used to update the root pointer in the tree of tree roots. | |
642 | * | |
643 | * But, in the case of the extent allocation tree, updating the root | |
644 | * pointer may allocate blocks which may change the root of the extent | |
645 | * allocation tree. | |
646 | * | |
647 | * So, this loops and repeats and makes sure the cowonly root didn't | |
648 | * change while the root pointer was being updated in the metadata. | |
649 | */ | |
0b86a832 CM |
650 | static int update_cowonly_root(struct btrfs_trans_handle *trans, |
651 | struct btrfs_root *root) | |
79154b1b CM |
652 | { |
653 | int ret; | |
0b86a832 | 654 | u64 old_root_bytenr; |
86b9f2ec | 655 | u64 old_root_used; |
0b86a832 | 656 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
79154b1b | 657 | |
86b9f2ec | 658 | old_root_used = btrfs_root_used(&root->root_item); |
0b86a832 | 659 | btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 660 | |
d397712b | 661 | while (1) { |
0b86a832 | 662 | old_root_bytenr = btrfs_root_bytenr(&root->root_item); |
86b9f2ec YZ |
663 | if (old_root_bytenr == root->node->start && |
664 | old_root_used == btrfs_root_used(&root->root_item)) | |
79154b1b | 665 | break; |
87ef2bb4 | 666 | |
5d4f98a2 | 667 | btrfs_set_root_node(&root->root_item, root->node); |
79154b1b | 668 | ret = btrfs_update_root(trans, tree_root, |
0b86a832 CM |
669 | &root->root_key, |
670 | &root->root_item); | |
79154b1b | 671 | BUG_ON(ret); |
56bec294 | 672 | |
86b9f2ec | 673 | old_root_used = btrfs_root_used(&root->root_item); |
4a8c9a62 | 674 | ret = btrfs_write_dirty_block_groups(trans, root); |
56bec294 | 675 | BUG_ON(ret); |
0b86a832 | 676 | } |
276e680d YZ |
677 | |
678 | if (root != root->fs_info->extent_root) | |
679 | switch_commit_root(root); | |
680 | ||
0b86a832 CM |
681 | return 0; |
682 | } | |
683 | ||
d352ac68 CM |
684 | /* |
685 | * update all the cowonly tree roots on disk | |
686 | */ | |
5d4f98a2 YZ |
687 | static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans, |
688 | struct btrfs_root *root) | |
0b86a832 CM |
689 | { |
690 | struct btrfs_fs_info *fs_info = root->fs_info; | |
691 | struct list_head *next; | |
84234f3a | 692 | struct extent_buffer *eb; |
56bec294 | 693 | int ret; |
84234f3a | 694 | |
56bec294 CM |
695 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
696 | BUG_ON(ret); | |
87ef2bb4 | 697 | |
84234f3a | 698 | eb = btrfs_lock_root_node(fs_info->tree_root); |
9fa8cfe7 | 699 | btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb); |
84234f3a YZ |
700 | btrfs_tree_unlock(eb); |
701 | free_extent_buffer(eb); | |
0b86a832 | 702 | |
56bec294 CM |
703 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
704 | BUG_ON(ret); | |
87ef2bb4 | 705 | |
d397712b | 706 | while (!list_empty(&fs_info->dirty_cowonly_roots)) { |
0b86a832 CM |
707 | next = fs_info->dirty_cowonly_roots.next; |
708 | list_del_init(next); | |
709 | root = list_entry(next, struct btrfs_root, dirty_list); | |
87ef2bb4 | 710 | |
0b86a832 | 711 | update_cowonly_root(trans, root); |
79154b1b | 712 | } |
276e680d YZ |
713 | |
714 | down_write(&fs_info->extent_commit_sem); | |
715 | switch_commit_root(fs_info->extent_root); | |
716 | up_write(&fs_info->extent_commit_sem); | |
717 | ||
79154b1b CM |
718 | return 0; |
719 | } | |
720 | ||
d352ac68 CM |
721 | /* |
722 | * dead roots are old snapshots that need to be deleted. This allocates | |
723 | * a dirty root struct and adds it into the list of dead roots that need to | |
724 | * be deleted | |
725 | */ | |
5d4f98a2 | 726 | int btrfs_add_dead_root(struct btrfs_root *root) |
5eda7b5e | 727 | { |
b48652c1 | 728 | mutex_lock(&root->fs_info->trans_mutex); |
5d4f98a2 | 729 | list_add(&root->root_list, &root->fs_info->dead_roots); |
b48652c1 | 730 | mutex_unlock(&root->fs_info->trans_mutex); |
5eda7b5e CM |
731 | return 0; |
732 | } | |
733 | ||
d352ac68 | 734 | /* |
5d4f98a2 | 735 | * update all the cowonly tree roots on disk |
d352ac68 | 736 | */ |
5d4f98a2 YZ |
737 | static noinline int commit_fs_roots(struct btrfs_trans_handle *trans, |
738 | struct btrfs_root *root) | |
0f7d52f4 | 739 | { |
0f7d52f4 | 740 | struct btrfs_root *gang[8]; |
5d4f98a2 | 741 | struct btrfs_fs_info *fs_info = root->fs_info; |
0f7d52f4 CM |
742 | int i; |
743 | int ret; | |
54aa1f4d CM |
744 | int err = 0; |
745 | ||
d397712b | 746 | while (1) { |
5d4f98a2 YZ |
747 | ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix, |
748 | (void **)gang, 0, | |
0f7d52f4 CM |
749 | ARRAY_SIZE(gang), |
750 | BTRFS_ROOT_TRANS_TAG); | |
751 | if (ret == 0) | |
752 | break; | |
753 | for (i = 0; i < ret; i++) { | |
754 | root = gang[i]; | |
5d4f98a2 YZ |
755 | radix_tree_tag_clear(&fs_info->fs_roots_radix, |
756 | (unsigned long)root->root_key.objectid, | |
757 | BTRFS_ROOT_TRANS_TAG); | |
31153d81 | 758 | |
e02119d5 | 759 | btrfs_free_log(trans, root); |
5d4f98a2 | 760 | btrfs_update_reloc_root(trans, root); |
d68fc57b | 761 | btrfs_orphan_commit_root(trans, root); |
bcc63abb | 762 | |
978d910d | 763 | if (root->commit_root != root->node) { |
817d52f8 | 764 | switch_commit_root(root); |
978d910d YZ |
765 | btrfs_set_root_node(&root->root_item, |
766 | root->node); | |
767 | } | |
5d4f98a2 | 768 | |
5d4f98a2 | 769 | err = btrfs_update_root(trans, fs_info->tree_root, |
0f7d52f4 CM |
770 | &root->root_key, |
771 | &root->root_item); | |
54aa1f4d CM |
772 | if (err) |
773 | break; | |
0f7d52f4 CM |
774 | } |
775 | } | |
54aa1f4d | 776 | return err; |
0f7d52f4 CM |
777 | } |
778 | ||
d352ac68 CM |
779 | /* |
780 | * defrag a given btree. If cacheonly == 1, this won't read from the disk, | |
781 | * otherwise every leaf in the btree is read and defragged. | |
782 | */ | |
e9d0b13b CM |
783 | int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) |
784 | { | |
785 | struct btrfs_fs_info *info = root->fs_info; | |
e9d0b13b | 786 | struct btrfs_trans_handle *trans; |
8929ecfa | 787 | int ret; |
d3c2fdcf | 788 | unsigned long nr; |
e9d0b13b | 789 | |
8929ecfa | 790 | if (xchg(&root->defrag_running, 1)) |
e9d0b13b | 791 | return 0; |
8929ecfa | 792 | |
6b80053d | 793 | while (1) { |
8929ecfa YZ |
794 | trans = btrfs_start_transaction(root, 0); |
795 | if (IS_ERR(trans)) | |
796 | return PTR_ERR(trans); | |
797 | ||
e9d0b13b | 798 | ret = btrfs_defrag_leaves(trans, root, cacheonly); |
8929ecfa | 799 | |
d3c2fdcf | 800 | nr = trans->blocks_used; |
e9d0b13b | 801 | btrfs_end_transaction(trans, root); |
d3c2fdcf | 802 | btrfs_btree_balance_dirty(info->tree_root, nr); |
e9d0b13b CM |
803 | cond_resched(); |
804 | ||
3f157a2f | 805 | if (root->fs_info->closing || ret != -EAGAIN) |
e9d0b13b CM |
806 | break; |
807 | } | |
808 | root->defrag_running = 0; | |
8929ecfa | 809 | return ret; |
e9d0b13b CM |
810 | } |
811 | ||
2c47e605 | 812 | #if 0 |
b7ec40d7 CM |
813 | /* |
814 | * when dropping snapshots, we generate a ton of delayed refs, and it makes | |
815 | * sense not to join the transaction while it is trying to flush the current | |
816 | * queue of delayed refs out. | |
817 | * | |
818 | * This is used by the drop snapshot code only | |
819 | */ | |
820 | static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info) | |
821 | { | |
822 | DEFINE_WAIT(wait); | |
823 | ||
824 | mutex_lock(&info->trans_mutex); | |
825 | while (info->running_transaction && | |
826 | info->running_transaction->delayed_refs.flushing) { | |
827 | prepare_to_wait(&info->transaction_wait, &wait, | |
828 | TASK_UNINTERRUPTIBLE); | |
829 | mutex_unlock(&info->trans_mutex); | |
59bc5c75 | 830 | |
b7ec40d7 | 831 | schedule(); |
59bc5c75 | 832 | |
b7ec40d7 CM |
833 | mutex_lock(&info->trans_mutex); |
834 | finish_wait(&info->transaction_wait, &wait); | |
835 | } | |
836 | mutex_unlock(&info->trans_mutex); | |
837 | return 0; | |
838 | } | |
839 | ||
d352ac68 CM |
840 | /* |
841 | * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on | |
842 | * all of them | |
843 | */ | |
5d4f98a2 | 844 | int btrfs_drop_dead_root(struct btrfs_root *root) |
0f7d52f4 | 845 | { |
0f7d52f4 | 846 | struct btrfs_trans_handle *trans; |
5d4f98a2 | 847 | struct btrfs_root *tree_root = root->fs_info->tree_root; |
d3c2fdcf | 848 | unsigned long nr; |
5d4f98a2 | 849 | int ret; |
58176a96 | 850 | |
5d4f98a2 YZ |
851 | while (1) { |
852 | /* | |
853 | * we don't want to jump in and create a bunch of | |
854 | * delayed refs if the transaction is starting to close | |
855 | */ | |
856 | wait_transaction_pre_flush(tree_root->fs_info); | |
857 | trans = btrfs_start_transaction(tree_root, 1); | |
a2135011 | 858 | |
5d4f98a2 YZ |
859 | /* |
860 | * we've joined a transaction, make sure it isn't | |
861 | * closing right now | |
862 | */ | |
863 | if (trans->transaction->delayed_refs.flushing) { | |
864 | btrfs_end_transaction(trans, tree_root); | |
865 | continue; | |
9f3a7427 | 866 | } |
58176a96 | 867 | |
5d4f98a2 YZ |
868 | ret = btrfs_drop_snapshot(trans, root); |
869 | if (ret != -EAGAIN) | |
870 | break; | |
a2135011 | 871 | |
5d4f98a2 YZ |
872 | ret = btrfs_update_root(trans, tree_root, |
873 | &root->root_key, | |
874 | &root->root_item); | |
875 | if (ret) | |
54aa1f4d | 876 | break; |
bcc63abb | 877 | |
d3c2fdcf | 878 | nr = trans->blocks_used; |
0f7d52f4 CM |
879 | ret = btrfs_end_transaction(trans, tree_root); |
880 | BUG_ON(ret); | |
5eda7b5e | 881 | |
d3c2fdcf | 882 | btrfs_btree_balance_dirty(tree_root, nr); |
4dc11904 | 883 | cond_resched(); |
0f7d52f4 | 884 | } |
5d4f98a2 YZ |
885 | BUG_ON(ret); |
886 | ||
887 | ret = btrfs_del_root(trans, tree_root, &root->root_key); | |
888 | BUG_ON(ret); | |
889 | ||
890 | nr = trans->blocks_used; | |
891 | ret = btrfs_end_transaction(trans, tree_root); | |
892 | BUG_ON(ret); | |
893 | ||
894 | free_extent_buffer(root->node); | |
895 | free_extent_buffer(root->commit_root); | |
896 | kfree(root); | |
897 | ||
898 | btrfs_btree_balance_dirty(tree_root, nr); | |
54aa1f4d | 899 | return ret; |
0f7d52f4 | 900 | } |
2c47e605 | 901 | #endif |
0f7d52f4 | 902 | |
d352ac68 CM |
903 | /* |
904 | * new snapshots need to be created at a very specific time in the | |
905 | * transaction commit. This does the actual creation | |
906 | */ | |
80b6794d | 907 | static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, |
3063d29f CM |
908 | struct btrfs_fs_info *fs_info, |
909 | struct btrfs_pending_snapshot *pending) | |
910 | { | |
911 | struct btrfs_key key; | |
80b6794d | 912 | struct btrfs_root_item *new_root_item; |
3063d29f CM |
913 | struct btrfs_root *tree_root = fs_info->tree_root; |
914 | struct btrfs_root *root = pending->root; | |
6bdb72de SW |
915 | struct btrfs_root *parent_root; |
916 | struct inode *parent_inode; | |
6a912213 | 917 | struct dentry *parent; |
a22285a6 | 918 | struct dentry *dentry; |
3063d29f | 919 | struct extent_buffer *tmp; |
925baedd | 920 | struct extent_buffer *old; |
3063d29f | 921 | int ret; |
d68fc57b | 922 | u64 to_reserve = 0; |
6bdb72de | 923 | u64 index = 0; |
a22285a6 | 924 | u64 objectid; |
b83cc969 | 925 | u64 root_flags; |
3063d29f | 926 | |
80b6794d CM |
927 | new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); |
928 | if (!new_root_item) { | |
a22285a6 | 929 | pending->error = -ENOMEM; |
80b6794d CM |
930 | goto fail; |
931 | } | |
a22285a6 | 932 | |
3063d29f | 933 | ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); |
a22285a6 YZ |
934 | if (ret) { |
935 | pending->error = ret; | |
3063d29f | 936 | goto fail; |
a22285a6 | 937 | } |
3063d29f | 938 | |
3fd0a558 | 939 | btrfs_reloc_pre_snapshot(trans, pending, &to_reserve); |
d68fc57b YZ |
940 | btrfs_orphan_pre_snapshot(trans, pending, &to_reserve); |
941 | ||
942 | if (to_reserve > 0) { | |
943 | ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv, | |
8bb8ab2e | 944 | to_reserve); |
d68fc57b YZ |
945 | if (ret) { |
946 | pending->error = ret; | |
947 | goto fail; | |
948 | } | |
949 | } | |
950 | ||
3063d29f | 951 | key.objectid = objectid; |
a22285a6 YZ |
952 | key.offset = (u64)-1; |
953 | key.type = BTRFS_ROOT_ITEM_KEY; | |
3063d29f | 954 | |
a22285a6 | 955 | trans->block_rsv = &pending->block_rsv; |
3de4586c | 956 | |
a22285a6 | 957 | dentry = pending->dentry; |
6a912213 JB |
958 | parent = dget_parent(dentry); |
959 | parent_inode = parent->d_inode; | |
a22285a6 | 960 | parent_root = BTRFS_I(parent_inode)->root; |
6bdb72de | 961 | record_root_in_trans(trans, parent_root); |
a22285a6 | 962 | |
3063d29f CM |
963 | /* |
964 | * insert the directory item | |
965 | */ | |
3de4586c | 966 | ret = btrfs_set_inode_index(parent_inode, &index); |
6bdb72de | 967 | BUG_ON(ret); |
0660b5af | 968 | ret = btrfs_insert_dir_item(trans, parent_root, |
a22285a6 YZ |
969 | dentry->d_name.name, dentry->d_name.len, |
970 | parent_inode->i_ino, &key, | |
971 | BTRFS_FT_DIR, index); | |
6bdb72de | 972 | BUG_ON(ret); |
0660b5af | 973 | |
a22285a6 YZ |
974 | btrfs_i_size_write(parent_inode, parent_inode->i_size + |
975 | dentry->d_name.len * 2); | |
52c26179 YZ |
976 | ret = btrfs_update_inode(trans, parent_root, parent_inode); |
977 | BUG_ON(ret); | |
978 | ||
6bdb72de SW |
979 | record_root_in_trans(trans, root); |
980 | btrfs_set_root_last_snapshot(&root->root_item, trans->transid); | |
981 | memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); | |
08fe4db1 | 982 | btrfs_check_and_init_root_item(new_root_item); |
6bdb72de | 983 | |
b83cc969 LZ |
984 | root_flags = btrfs_root_flags(new_root_item); |
985 | if (pending->readonly) | |
986 | root_flags |= BTRFS_ROOT_SUBVOL_RDONLY; | |
987 | else | |
988 | root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY; | |
989 | btrfs_set_root_flags(new_root_item, root_flags); | |
990 | ||
6bdb72de SW |
991 | old = btrfs_lock_root_node(root); |
992 | btrfs_cow_block(trans, root, old, NULL, 0, &old); | |
993 | btrfs_set_lock_blocking(old); | |
994 | ||
995 | btrfs_copy_root(trans, root, old, &tmp, objectid); | |
996 | btrfs_tree_unlock(old); | |
997 | free_extent_buffer(old); | |
998 | ||
999 | btrfs_set_root_node(new_root_item, tmp); | |
a22285a6 YZ |
1000 | /* record when the snapshot was created in key.offset */ |
1001 | key.offset = trans->transid; | |
1002 | ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); | |
6bdb72de SW |
1003 | btrfs_tree_unlock(tmp); |
1004 | free_extent_buffer(tmp); | |
a22285a6 | 1005 | BUG_ON(ret); |
6bdb72de | 1006 | |
a22285a6 YZ |
1007 | /* |
1008 | * insert root back/forward references | |
1009 | */ | |
1010 | ret = btrfs_add_root_ref(trans, tree_root, objectid, | |
0660b5af | 1011 | parent_root->root_key.objectid, |
a22285a6 YZ |
1012 | parent_inode->i_ino, index, |
1013 | dentry->d_name.name, dentry->d_name.len); | |
0660b5af | 1014 | BUG_ON(ret); |
6a912213 | 1015 | dput(parent); |
0660b5af | 1016 | |
a22285a6 YZ |
1017 | key.offset = (u64)-1; |
1018 | pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); | |
1019 | BUG_ON(IS_ERR(pending->snap)); | |
d68fc57b | 1020 | |
3fd0a558 | 1021 | btrfs_reloc_post_snapshot(trans, pending); |
d68fc57b | 1022 | btrfs_orphan_post_snapshot(trans, pending); |
3063d29f | 1023 | fail: |
6bdb72de | 1024 | kfree(new_root_item); |
a22285a6 YZ |
1025 | btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); |
1026 | return 0; | |
3063d29f CM |
1027 | } |
1028 | ||
d352ac68 CM |
1029 | /* |
1030 | * create all the snapshots we've scheduled for creation | |
1031 | */ | |
80b6794d CM |
1032 | static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, |
1033 | struct btrfs_fs_info *fs_info) | |
3de4586c CM |
1034 | { |
1035 | struct btrfs_pending_snapshot *pending; | |
1036 | struct list_head *head = &trans->transaction->pending_snapshots; | |
3de4586c CM |
1037 | int ret; |
1038 | ||
c6e30871 | 1039 | list_for_each_entry(pending, head, list) { |
3de4586c CM |
1040 | ret = create_pending_snapshot(trans, fs_info, pending); |
1041 | BUG_ON(ret); | |
1042 | } | |
1043 | return 0; | |
1044 | } | |
1045 | ||
5d4f98a2 YZ |
1046 | static void update_super_roots(struct btrfs_root *root) |
1047 | { | |
1048 | struct btrfs_root_item *root_item; | |
1049 | struct btrfs_super_block *super; | |
1050 | ||
1051 | super = &root->fs_info->super_copy; | |
1052 | ||
1053 | root_item = &root->fs_info->chunk_root->root_item; | |
1054 | super->chunk_root = root_item->bytenr; | |
1055 | super->chunk_root_generation = root_item->generation; | |
1056 | super->chunk_root_level = root_item->level; | |
1057 | ||
1058 | root_item = &root->fs_info->tree_root->root_item; | |
1059 | super->root = root_item->bytenr; | |
1060 | super->generation = root_item->generation; | |
1061 | super->root_level = root_item->level; | |
0af3d00b JB |
1062 | if (super->cache_generation != 0 || btrfs_test_opt(root, SPACE_CACHE)) |
1063 | super->cache_generation = root_item->generation; | |
5d4f98a2 YZ |
1064 | } |
1065 | ||
f36f3042 CM |
1066 | int btrfs_transaction_in_commit(struct btrfs_fs_info *info) |
1067 | { | |
1068 | int ret = 0; | |
1069 | spin_lock(&info->new_trans_lock); | |
1070 | if (info->running_transaction) | |
1071 | ret = info->running_transaction->in_commit; | |
1072 | spin_unlock(&info->new_trans_lock); | |
1073 | return ret; | |
1074 | } | |
1075 | ||
8929ecfa YZ |
1076 | int btrfs_transaction_blocked(struct btrfs_fs_info *info) |
1077 | { | |
1078 | int ret = 0; | |
1079 | spin_lock(&info->new_trans_lock); | |
1080 | if (info->running_transaction) | |
1081 | ret = info->running_transaction->blocked; | |
1082 | spin_unlock(&info->new_trans_lock); | |
1083 | return ret; | |
1084 | } | |
1085 | ||
bb9c12c9 SW |
1086 | /* |
1087 | * wait for the current transaction commit to start and block subsequent | |
1088 | * transaction joins | |
1089 | */ | |
1090 | static void wait_current_trans_commit_start(struct btrfs_root *root, | |
1091 | struct btrfs_transaction *trans) | |
1092 | { | |
1093 | DEFINE_WAIT(wait); | |
1094 | ||
1095 | if (trans->in_commit) | |
1096 | return; | |
1097 | ||
1098 | while (1) { | |
1099 | prepare_to_wait(&root->fs_info->transaction_blocked_wait, &wait, | |
1100 | TASK_UNINTERRUPTIBLE); | |
1101 | if (trans->in_commit) { | |
1102 | finish_wait(&root->fs_info->transaction_blocked_wait, | |
1103 | &wait); | |
1104 | break; | |
1105 | } | |
1106 | mutex_unlock(&root->fs_info->trans_mutex); | |
1107 | schedule(); | |
1108 | mutex_lock(&root->fs_info->trans_mutex); | |
1109 | finish_wait(&root->fs_info->transaction_blocked_wait, &wait); | |
1110 | } | |
1111 | } | |
1112 | ||
1113 | /* | |
1114 | * wait for the current transaction to start and then become unblocked. | |
1115 | * caller holds ref. | |
1116 | */ | |
1117 | static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root, | |
1118 | struct btrfs_transaction *trans) | |
1119 | { | |
1120 | DEFINE_WAIT(wait); | |
1121 | ||
1122 | if (trans->commit_done || (trans->in_commit && !trans->blocked)) | |
1123 | return; | |
1124 | ||
1125 | while (1) { | |
1126 | prepare_to_wait(&root->fs_info->transaction_wait, &wait, | |
1127 | TASK_UNINTERRUPTIBLE); | |
1128 | if (trans->commit_done || | |
1129 | (trans->in_commit && !trans->blocked)) { | |
1130 | finish_wait(&root->fs_info->transaction_wait, | |
1131 | &wait); | |
1132 | break; | |
1133 | } | |
1134 | mutex_unlock(&root->fs_info->trans_mutex); | |
1135 | schedule(); | |
1136 | mutex_lock(&root->fs_info->trans_mutex); | |
1137 | finish_wait(&root->fs_info->transaction_wait, | |
1138 | &wait); | |
1139 | } | |
1140 | } | |
1141 | ||
1142 | /* | |
1143 | * commit transactions asynchronously. once btrfs_commit_transaction_async | |
1144 | * returns, any subsequent transaction will not be allowed to join. | |
1145 | */ | |
1146 | struct btrfs_async_commit { | |
1147 | struct btrfs_trans_handle *newtrans; | |
1148 | struct btrfs_root *root; | |
1149 | struct delayed_work work; | |
1150 | }; | |
1151 | ||
1152 | static void do_async_commit(struct work_struct *work) | |
1153 | { | |
1154 | struct btrfs_async_commit *ac = | |
1155 | container_of(work, struct btrfs_async_commit, work.work); | |
1156 | ||
1157 | btrfs_commit_transaction(ac->newtrans, ac->root); | |
1158 | kfree(ac); | |
1159 | } | |
1160 | ||
1161 | int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans, | |
1162 | struct btrfs_root *root, | |
1163 | int wait_for_unblock) | |
1164 | { | |
1165 | struct btrfs_async_commit *ac; | |
1166 | struct btrfs_transaction *cur_trans; | |
1167 | ||
1168 | ac = kmalloc(sizeof(*ac), GFP_NOFS); | |
db5b493a TI |
1169 | if (!ac) |
1170 | return -ENOMEM; | |
bb9c12c9 SW |
1171 | |
1172 | INIT_DELAYED_WORK(&ac->work, do_async_commit); | |
1173 | ac->root = root; | |
1174 | ac->newtrans = btrfs_join_transaction(root, 0); | |
3612b495 TI |
1175 | if (IS_ERR(ac->newtrans)) { |
1176 | int err = PTR_ERR(ac->newtrans); | |
1177 | kfree(ac); | |
1178 | return err; | |
1179 | } | |
bb9c12c9 SW |
1180 | |
1181 | /* take transaction reference */ | |
1182 | mutex_lock(&root->fs_info->trans_mutex); | |
1183 | cur_trans = trans->transaction; | |
13c5a93e | 1184 | atomic_inc(&cur_trans->use_count); |
bb9c12c9 SW |
1185 | mutex_unlock(&root->fs_info->trans_mutex); |
1186 | ||
1187 | btrfs_end_transaction(trans, root); | |
1188 | schedule_delayed_work(&ac->work, 0); | |
1189 | ||
1190 | /* wait for transaction to start and unblock */ | |
1191 | mutex_lock(&root->fs_info->trans_mutex); | |
1192 | if (wait_for_unblock) | |
1193 | wait_current_trans_commit_start_and_unblock(root, cur_trans); | |
1194 | else | |
1195 | wait_current_trans_commit_start(root, cur_trans); | |
1196 | put_transaction(cur_trans); | |
1197 | mutex_unlock(&root->fs_info->trans_mutex); | |
1198 | ||
1199 | return 0; | |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | * btrfs_transaction state sequence: | |
1204 | * in_commit = 0, blocked = 0 (initial) | |
1205 | * in_commit = 1, blocked = 1 | |
1206 | * blocked = 0 | |
1207 | * commit_done = 1 | |
1208 | */ | |
79154b1b CM |
1209 | int btrfs_commit_transaction(struct btrfs_trans_handle *trans, |
1210 | struct btrfs_root *root) | |
1211 | { | |
15ee9bc7 | 1212 | unsigned long joined = 0; |
79154b1b | 1213 | struct btrfs_transaction *cur_trans; |
8fd17795 | 1214 | struct btrfs_transaction *prev_trans = NULL; |
79154b1b | 1215 | DEFINE_WAIT(wait); |
15ee9bc7 | 1216 | int ret; |
89573b9c CM |
1217 | int should_grow = 0; |
1218 | unsigned long now = get_seconds(); | |
dccae999 | 1219 | int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT); |
79154b1b | 1220 | |
5a3f23d5 CM |
1221 | btrfs_run_ordered_operations(root, 0); |
1222 | ||
56bec294 CM |
1223 | /* make a pass through all the delayed refs we have so far |
1224 | * any runnings procs may add more while we are here | |
1225 | */ | |
1226 | ret = btrfs_run_delayed_refs(trans, root, 0); | |
1227 | BUG_ON(ret); | |
1228 | ||
a22285a6 YZ |
1229 | btrfs_trans_release_metadata(trans, root); |
1230 | ||
b7ec40d7 | 1231 | cur_trans = trans->transaction; |
56bec294 CM |
1232 | /* |
1233 | * set the flushing flag so procs in this transaction have to | |
1234 | * start sending their work down. | |
1235 | */ | |
b7ec40d7 | 1236 | cur_trans->delayed_refs.flushing = 1; |
56bec294 | 1237 | |
c3e69d58 | 1238 | ret = btrfs_run_delayed_refs(trans, root, 0); |
56bec294 CM |
1239 | BUG_ON(ret); |
1240 | ||
79154b1b | 1241 | mutex_lock(&root->fs_info->trans_mutex); |
b7ec40d7 | 1242 | if (cur_trans->in_commit) { |
13c5a93e | 1243 | atomic_inc(&cur_trans->use_count); |
ccd467d6 | 1244 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b | 1245 | btrfs_end_transaction(trans, root); |
ccd467d6 | 1246 | |
79154b1b CM |
1247 | ret = wait_for_commit(root, cur_trans); |
1248 | BUG_ON(ret); | |
15ee9bc7 JB |
1249 | |
1250 | mutex_lock(&root->fs_info->trans_mutex); | |
79154b1b | 1251 | put_transaction(cur_trans); |
15ee9bc7 JB |
1252 | mutex_unlock(&root->fs_info->trans_mutex); |
1253 | ||
79154b1b CM |
1254 | return 0; |
1255 | } | |
4313b399 | 1256 | |
2c90e5d6 | 1257 | trans->transaction->in_commit = 1; |
f9295749 | 1258 | trans->transaction->blocked = 1; |
bb9c12c9 SW |
1259 | wake_up(&root->fs_info->transaction_blocked_wait); |
1260 | ||
ccd467d6 CM |
1261 | if (cur_trans->list.prev != &root->fs_info->trans_list) { |
1262 | prev_trans = list_entry(cur_trans->list.prev, | |
1263 | struct btrfs_transaction, list); | |
1264 | if (!prev_trans->commit_done) { | |
13c5a93e | 1265 | atomic_inc(&prev_trans->use_count); |
ccd467d6 CM |
1266 | mutex_unlock(&root->fs_info->trans_mutex); |
1267 | ||
1268 | wait_for_commit(root, prev_trans); | |
ccd467d6 | 1269 | |
ccd467d6 | 1270 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1271 | put_transaction(prev_trans); |
ccd467d6 CM |
1272 | } |
1273 | } | |
15ee9bc7 | 1274 | |
89573b9c CM |
1275 | if (now < cur_trans->start_time || now - cur_trans->start_time < 1) |
1276 | should_grow = 1; | |
1277 | ||
15ee9bc7 | 1278 | do { |
7ea394f1 | 1279 | int snap_pending = 0; |
15ee9bc7 | 1280 | joined = cur_trans->num_joined; |
7ea394f1 YZ |
1281 | if (!list_empty(&trans->transaction->pending_snapshots)) |
1282 | snap_pending = 1; | |
1283 | ||
2c90e5d6 | 1284 | WARN_ON(cur_trans != trans->transaction); |
79154b1b | 1285 | mutex_unlock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1286 | |
0bdb1db2 | 1287 | if (flush_on_commit || snap_pending) { |
24bbcf04 YZ |
1288 | btrfs_start_delalloc_inodes(root, 1); |
1289 | ret = btrfs_wait_ordered_extents(root, 0, 1); | |
ebecd3d9 | 1290 | BUG_ON(ret); |
7ea394f1 YZ |
1291 | } |
1292 | ||
5a3f23d5 CM |
1293 | /* |
1294 | * rename don't use btrfs_join_transaction, so, once we | |
1295 | * set the transaction to blocked above, we aren't going | |
1296 | * to get any new ordered operations. We can safely run | |
1297 | * it here and no for sure that nothing new will be added | |
1298 | * to the list | |
1299 | */ | |
1300 | btrfs_run_ordered_operations(root, 1); | |
1301 | ||
ed3b3d31 CM |
1302 | prepare_to_wait(&cur_trans->writer_wait, &wait, |
1303 | TASK_UNINTERRUPTIBLE); | |
1304 | ||
89573b9c | 1305 | smp_mb(); |
13c5a93e | 1306 | if (atomic_read(&cur_trans->num_writers) > 1) |
99d16cbc SW |
1307 | schedule_timeout(MAX_SCHEDULE_TIMEOUT); |
1308 | else if (should_grow) | |
1309 | schedule_timeout(1); | |
15ee9bc7 | 1310 | |
79154b1b | 1311 | mutex_lock(&root->fs_info->trans_mutex); |
15ee9bc7 | 1312 | finish_wait(&cur_trans->writer_wait, &wait); |
13c5a93e | 1313 | } while (atomic_read(&cur_trans->num_writers) > 1 || |
89573b9c | 1314 | (should_grow && cur_trans->num_joined != joined)); |
15ee9bc7 | 1315 | |
3063d29f CM |
1316 | ret = create_pending_snapshots(trans, root->fs_info); |
1317 | BUG_ON(ret); | |
1318 | ||
56bec294 CM |
1319 | ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); |
1320 | BUG_ON(ret); | |
1321 | ||
2c90e5d6 | 1322 | WARN_ON(cur_trans != trans->transaction); |
dc17ff8f | 1323 | |
e02119d5 CM |
1324 | /* btrfs_commit_tree_roots is responsible for getting the |
1325 | * various roots consistent with each other. Every pointer | |
1326 | * in the tree of tree roots has to point to the most up to date | |
1327 | * root for every subvolume and other tree. So, we have to keep | |
1328 | * the tree logging code from jumping in and changing any | |
1329 | * of the trees. | |
1330 | * | |
1331 | * At this point in the commit, there can't be any tree-log | |
1332 | * writers, but a little lower down we drop the trans mutex | |
1333 | * and let new people in. By holding the tree_log_mutex | |
1334 | * from now until after the super is written, we avoid races | |
1335 | * with the tree-log code. | |
1336 | */ | |
1337 | mutex_lock(&root->fs_info->tree_log_mutex); | |
1338 | ||
5d4f98a2 | 1339 | ret = commit_fs_roots(trans, root); |
54aa1f4d CM |
1340 | BUG_ON(ret); |
1341 | ||
5d4f98a2 | 1342 | /* commit_fs_roots gets rid of all the tree log roots, it is now |
e02119d5 CM |
1343 | * safe to free the root of tree log roots |
1344 | */ | |
1345 | btrfs_free_log_root_tree(trans, root->fs_info); | |
1346 | ||
5d4f98a2 | 1347 | ret = commit_cowonly_roots(trans, root); |
79154b1b | 1348 | BUG_ON(ret); |
54aa1f4d | 1349 | |
11833d66 YZ |
1350 | btrfs_prepare_extent_commit(trans, root); |
1351 | ||
78fae27e | 1352 | cur_trans = root->fs_info->running_transaction; |
cee36a03 | 1353 | spin_lock(&root->fs_info->new_trans_lock); |
78fae27e | 1354 | root->fs_info->running_transaction = NULL; |
cee36a03 | 1355 | spin_unlock(&root->fs_info->new_trans_lock); |
5d4f98a2 YZ |
1356 | |
1357 | btrfs_set_root_node(&root->fs_info->tree_root->root_item, | |
1358 | root->fs_info->tree_root->node); | |
817d52f8 | 1359 | switch_commit_root(root->fs_info->tree_root); |
5d4f98a2 YZ |
1360 | |
1361 | btrfs_set_root_node(&root->fs_info->chunk_root->root_item, | |
1362 | root->fs_info->chunk_root->node); | |
817d52f8 | 1363 | switch_commit_root(root->fs_info->chunk_root); |
5d4f98a2 YZ |
1364 | |
1365 | update_super_roots(root); | |
e02119d5 CM |
1366 | |
1367 | if (!root->fs_info->log_root_recovering) { | |
1368 | btrfs_set_super_log_root(&root->fs_info->super_copy, 0); | |
1369 | btrfs_set_super_log_root_level(&root->fs_info->super_copy, 0); | |
1370 | } | |
1371 | ||
a061fc8d CM |
1372 | memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, |
1373 | sizeof(root->fs_info->super_copy)); | |
ccd467d6 | 1374 | |
f9295749 | 1375 | trans->transaction->blocked = 0; |
b7ec40d7 | 1376 | |
f9295749 | 1377 | wake_up(&root->fs_info->transaction_wait); |
e6dcd2dc | 1378 | |
78fae27e | 1379 | mutex_unlock(&root->fs_info->trans_mutex); |
79154b1b CM |
1380 | ret = btrfs_write_and_wait_transaction(trans, root); |
1381 | BUG_ON(ret); | |
a512bbf8 | 1382 | write_ctree_super(trans, root, 0); |
4313b399 | 1383 | |
e02119d5 CM |
1384 | /* |
1385 | * the super is written, we can safely allow the tree-loggers | |
1386 | * to go about their business | |
1387 | */ | |
1388 | mutex_unlock(&root->fs_info->tree_log_mutex); | |
1389 | ||
11833d66 | 1390 | btrfs_finish_extent_commit(trans, root); |
4313b399 | 1391 | |
1a40e23b ZY |
1392 | mutex_lock(&root->fs_info->trans_mutex); |
1393 | ||
2c90e5d6 | 1394 | cur_trans->commit_done = 1; |
b7ec40d7 | 1395 | |
15ee9bc7 | 1396 | root->fs_info->last_trans_committed = cur_trans->transid; |
817d52f8 | 1397 | |
2c90e5d6 | 1398 | wake_up(&cur_trans->commit_wait); |
3de4586c | 1399 | |
13c5a93e | 1400 | list_del_init(&cur_trans->list); |
78fae27e | 1401 | put_transaction(cur_trans); |
79154b1b | 1402 | put_transaction(cur_trans); |
58176a96 | 1403 | |
1abe9b8a | 1404 | trace_btrfs_transaction_commit(root); |
1405 | ||
78fae27e | 1406 | mutex_unlock(&root->fs_info->trans_mutex); |
3de4586c | 1407 | |
9ed74f2d JB |
1408 | if (current->journal_info == trans) |
1409 | current->journal_info = NULL; | |
1410 | ||
2c90e5d6 | 1411 | kmem_cache_free(btrfs_trans_handle_cachep, trans); |
24bbcf04 YZ |
1412 | |
1413 | if (current != root->fs_info->transaction_kthread) | |
1414 | btrfs_run_delayed_iputs(root); | |
1415 | ||
79154b1b CM |
1416 | return ret; |
1417 | } | |
1418 | ||
d352ac68 CM |
1419 | /* |
1420 | * interface function to delete all the snapshots we have scheduled for deletion | |
1421 | */ | |
e9d0b13b CM |
1422 | int btrfs_clean_old_snapshots(struct btrfs_root *root) |
1423 | { | |
5d4f98a2 YZ |
1424 | LIST_HEAD(list); |
1425 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1426 | ||
1427 | mutex_lock(&fs_info->trans_mutex); | |
1428 | list_splice_init(&fs_info->dead_roots, &list); | |
1429 | mutex_unlock(&fs_info->trans_mutex); | |
e9d0b13b | 1430 | |
5d4f98a2 YZ |
1431 | while (!list_empty(&list)) { |
1432 | root = list_entry(list.next, struct btrfs_root, root_list); | |
76dda93c YZ |
1433 | list_del(&root->root_list); |
1434 | ||
1435 | if (btrfs_header_backref_rev(root->node) < | |
1436 | BTRFS_MIXED_BACKREF_REV) | |
3fd0a558 | 1437 | btrfs_drop_snapshot(root, NULL, 0); |
76dda93c | 1438 | else |
3fd0a558 | 1439 | btrfs_drop_snapshot(root, NULL, 1); |
e9d0b13b CM |
1440 | } |
1441 | return 0; | |
1442 | } |