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btrfs: qgroup: inherit limit info from srcgroup in creating snapshot.
[linux-2.6/btrfs-unstable.git] / fs / btrfs / qgroup.c
blob34c2753fa4e18bddd23ad22379df496cb5ecc462
1 /*
2 * Copyright (C) 2011 STRATO. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/sched.h>
20 #include <linux/pagemap.h>
21 #include <linux/writeback.h>
22 #include <linux/blkdev.h>
23 #include <linux/rbtree.h>
24 #include <linux/slab.h>
25 #include <linux/workqueue.h>
26 #include <linux/btrfs.h>
27
28 #include "ctree.h"
29 #include "transaction.h"
30 #include "disk-io.h"
31 #include "locking.h"
32 #include "ulist.h"
33 #include "backref.h"
34 #include "extent_io.h"
35 #include "qgroup.h"
36
37 /* TODO XXX FIXME
38 * - subvol delete -> delete when ref goes to 0? delete limits also?
39 * - reorganize keys
40 * - compressed
41 * - sync
42 * - copy also limits on subvol creation
43 * - limit
44 * - caches fuer ulists
45 * - performance benchmarks
46 * - check all ioctl parameters
47 */
48
49 /*
50 * one struct for each qgroup, organized in fs_info->qgroup_tree.
51 */
52 struct btrfs_qgroup {
53 u64 qgroupid;
54
55 /*
56 * state
57 */
58 u64 rfer; /* referenced */
59 u64 rfer_cmpr; /* referenced compressed */
60 u64 excl; /* exclusive */
61 u64 excl_cmpr; /* exclusive compressed */
62
63 /*
64 * limits
65 */
66 u64 lim_flags; /* which limits are set */
67 u64 max_rfer;
68 u64 max_excl;
69 u64 rsv_rfer;
70 u64 rsv_excl;
71
72 /*
73 * reservation tracking
74 */
75 u64 reserved;
76
77 /*
78 * lists
79 */
80 struct list_head groups; /* groups this group is member of */
81 struct list_head members; /* groups that are members of this group */
82 struct list_head dirty; /* dirty groups */
83 struct rb_node node; /* tree of qgroups */
84
85 /*
86 * temp variables for accounting operations
87 */
88 u64 old_refcnt;
89 u64 new_refcnt;
90 };
91
92 /*
93 * glue structure to represent the relations between qgroups.
94 */
95 struct btrfs_qgroup_list {
96 struct list_head next_group;
97 struct list_head next_member;
98 struct btrfs_qgroup *group;
99 struct btrfs_qgroup *member;
100 };
101
102 #define ptr_to_u64(x) ((u64)(uintptr_t)x)
103 #define u64_to_ptr(x) ((struct btrfs_qgroup *)(uintptr_t)x)
104
105 static int
106 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
107 int init_flags);
108 static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
109
110 /* must be called with qgroup_ioctl_lock held */
111 static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
112 u64 qgroupid)
113 {
114 struct rb_node *n = fs_info->qgroup_tree.rb_node;
115 struct btrfs_qgroup *qgroup;
116
117 while (n) {
118 qgroup = rb_entry(n, struct btrfs_qgroup, node);
119 if (qgroup->qgroupid < qgroupid)
120 n = n->rb_left;
121 else if (qgroup->qgroupid > qgroupid)
122 n = n->rb_right;
123 else
124 return qgroup;
125 }
126 return NULL;
127 }
128
129 /* must be called with qgroup_lock held */
130 static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
131 u64 qgroupid)
132 {
133 struct rb_node **p = &fs_info->qgroup_tree.rb_node;
134 struct rb_node *parent = NULL;
135 struct btrfs_qgroup *qgroup;
136
137 while (*p) {
138 parent = *p;
139 qgroup = rb_entry(parent, struct btrfs_qgroup, node);
140
141 if (qgroup->qgroupid < qgroupid)
142 p = &(*p)->rb_left;
143 else if (qgroup->qgroupid > qgroupid)
144 p = &(*p)->rb_right;
145 else
146 return qgroup;
147 }
148
149 qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
150 if (!qgroup)
151 return ERR_PTR(-ENOMEM);
152
153 qgroup->qgroupid = qgroupid;
154 INIT_LIST_HEAD(&qgroup->groups);
155 INIT_LIST_HEAD(&qgroup->members);
156 INIT_LIST_HEAD(&qgroup->dirty);
157
158 rb_link_node(&qgroup->node, parent, p);
159 rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
160
161 return qgroup;
162 }
163
164 static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
165 {
166 struct btrfs_qgroup_list *list;
167
168 list_del(&qgroup->dirty);
169 while (!list_empty(&qgroup->groups)) {
170 list = list_first_entry(&qgroup->groups,
171 struct btrfs_qgroup_list, next_group);
172 list_del(&list->next_group);
173 list_del(&list->next_member);
174 kfree(list);
175 }
176
177 while (!list_empty(&qgroup->members)) {
178 list = list_first_entry(&qgroup->members,
179 struct btrfs_qgroup_list, next_member);
180 list_del(&list->next_group);
181 list_del(&list->next_member);
182 kfree(list);
183 }
184 kfree(qgroup);
185 }
186
187 /* must be called with qgroup_lock held */
188 static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
189 {
190 struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
191
192 if (!qgroup)
193 return -ENOENT;
194
195 rb_erase(&qgroup->node, &fs_info->qgroup_tree);
196 __del_qgroup_rb(qgroup);
197 return 0;
198 }
199
200 /* must be called with qgroup_lock held */
201 static int add_relation_rb(struct btrfs_fs_info *fs_info,
202 u64 memberid, u64 parentid)
203 {
204 struct btrfs_qgroup *member;
205 struct btrfs_qgroup *parent;
206 struct btrfs_qgroup_list *list;
207
208 member = find_qgroup_rb(fs_info, memberid);
209 parent = find_qgroup_rb(fs_info, parentid);
210 if (!member || !parent)
211 return -ENOENT;
212
213 list = kzalloc(sizeof(*list), GFP_ATOMIC);
214 if (!list)
215 return -ENOMEM;
216
217 list->group = parent;
218 list->member = member;
219 list_add_tail(&list->next_group, &member->groups);
220 list_add_tail(&list->next_member, &parent->members);
221
222 return 0;
223 }
224
225 /* must be called with qgroup_lock held */
226 static int del_relation_rb(struct btrfs_fs_info *fs_info,
227 u64 memberid, u64 parentid)
228 {
229 struct btrfs_qgroup *member;
230 struct btrfs_qgroup *parent;
231 struct btrfs_qgroup_list *list;
232
233 member = find_qgroup_rb(fs_info, memberid);
234 parent = find_qgroup_rb(fs_info, parentid);
235 if (!member || !parent)
236 return -ENOENT;
237
238 list_for_each_entry(list, &member->groups, next_group) {
239 if (list->group == parent) {
240 list_del(&list->next_group);
241 list_del(&list->next_member);
242 kfree(list);
243 return 0;
244 }
245 }
246 return -ENOENT;
247 }
248
249 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
250 int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
251 u64 rfer, u64 excl)
252 {
253 struct btrfs_qgroup *qgroup;
254
255 qgroup = find_qgroup_rb(fs_info, qgroupid);
256 if (!qgroup)
257 return -EINVAL;
258 if (qgroup->rfer != rfer || qgroup->excl != excl)
259 return -EINVAL;
260 return 0;
261 }
262 #endif
263
264 /*
265 * The full config is read in one go, only called from open_ctree()
266 * It doesn't use any locking, as at this point we're still single-threaded
267 */
268 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
269 {
270 struct btrfs_key key;
271 struct btrfs_key found_key;
272 struct btrfs_root *quota_root = fs_info->quota_root;
273 struct btrfs_path *path = NULL;
274 struct extent_buffer *l;
275 int slot;
276 int ret = 0;
277 u64 flags = 0;
278 u64 rescan_progress = 0;
279
280 if (!fs_info->quota_enabled)
281 return 0;
282
283 fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
284 if (!fs_info->qgroup_ulist) {
285 ret = -ENOMEM;
286 goto out;
287 }
288
289 path = btrfs_alloc_path();
290 if (!path) {
291 ret = -ENOMEM;
292 goto out;
293 }
294
295 /* default this to quota off, in case no status key is found */
296 fs_info->qgroup_flags = 0;
297
298 /*
299 * pass 1: read status, all qgroup infos and limits
300 */
301 key.objectid = 0;
302 key.type = 0;
303 key.offset = 0;
304 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
305 if (ret)
306 goto out;
307
308 while (1) {
309 struct btrfs_qgroup *qgroup;
310
311 slot = path->slots[0];
312 l = path->nodes[0];
313 btrfs_item_key_to_cpu(l, &found_key, slot);
314
315 if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
316 struct btrfs_qgroup_status_item *ptr;
317
318 ptr = btrfs_item_ptr(l, slot,
319 struct btrfs_qgroup_status_item);
320
321 if (btrfs_qgroup_status_version(l, ptr) !=
322 BTRFS_QGROUP_STATUS_VERSION) {
323 btrfs_err(fs_info,
324 "old qgroup version, quota disabled");
325 goto out;
326 }
327 if (btrfs_qgroup_status_generation(l, ptr) !=
328 fs_info->generation) {
329 flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
330 btrfs_err(fs_info,
331 "qgroup generation mismatch, "
332 "marked as inconsistent");
333 }
334 fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
335 ptr);
336 rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
337 goto next1;
338 }
339
340 if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
341 found_key.type != BTRFS_QGROUP_LIMIT_KEY)
342 goto next1;
343
344 qgroup = find_qgroup_rb(fs_info, found_key.offset);
345 if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
346 (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
347 btrfs_err(fs_info, "inconsitent qgroup config");
348 flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
349 }
350 if (!qgroup) {
351 qgroup = add_qgroup_rb(fs_info, found_key.offset);
352 if (IS_ERR(qgroup)) {
353 ret = PTR_ERR(qgroup);
354 goto out;
355 }
356 }
357 switch (found_key.type) {
358 case BTRFS_QGROUP_INFO_KEY: {
359 struct btrfs_qgroup_info_item *ptr;
360
361 ptr = btrfs_item_ptr(l, slot,
362 struct btrfs_qgroup_info_item);
363 qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
364 qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
365 qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
366 qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
367 /* generation currently unused */
368 break;
369 }
370 case BTRFS_QGROUP_LIMIT_KEY: {
371 struct btrfs_qgroup_limit_item *ptr;
372
373 ptr = btrfs_item_ptr(l, slot,
374 struct btrfs_qgroup_limit_item);
375 qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
376 qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
377 qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
378 qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
379 qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
380 break;
381 }
382 }
383 next1:
384 ret = btrfs_next_item(quota_root, path);
385 if (ret < 0)
386 goto out;
387 if (ret)
388 break;
389 }
390 btrfs_release_path(path);
391
392 /*
393 * pass 2: read all qgroup relations
394 */
395 key.objectid = 0;
396 key.type = BTRFS_QGROUP_RELATION_KEY;
397 key.offset = 0;
398 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
399 if (ret)
400 goto out;
401 while (1) {
402 slot = path->slots[0];
403 l = path->nodes[0];
404 btrfs_item_key_to_cpu(l, &found_key, slot);
405
406 if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
407 goto next2;
408
409 if (found_key.objectid > found_key.offset) {
410 /* parent <- member, not needed to build config */
411 /* FIXME should we omit the key completely? */
412 goto next2;
413 }
414
415 ret = add_relation_rb(fs_info, found_key.objectid,
416 found_key.offset);
417 if (ret == -ENOENT) {
418 btrfs_warn(fs_info,
419 "orphan qgroup relation 0x%llx->0x%llx",
420 found_key.objectid, found_key.offset);
421 ret = 0; /* ignore the error */
422 }
423 if (ret)
424 goto out;
425 next2:
426 ret = btrfs_next_item(quota_root, path);
427 if (ret < 0)
428 goto out;
429 if (ret)
430 break;
431 }
432 out:
433 fs_info->qgroup_flags |= flags;
434 if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) {
435 fs_info->quota_enabled = 0;
436 fs_info->pending_quota_state = 0;
437 } else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
438 ret >= 0) {
439 ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
440 }
441 btrfs_free_path(path);
442
443 if (ret < 0) {
444 ulist_free(fs_info->qgroup_ulist);
445 fs_info->qgroup_ulist = NULL;
446 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
447 }
448
449 return ret < 0 ? ret : 0;
450 }
451
452 /*
453 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
454 * first two are in single-threaded paths.And for the third one, we have set
455 * quota_root to be null with qgroup_lock held before, so it is safe to clean
456 * up the in-memory structures without qgroup_lock held.
457 */
458 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
459 {
460 struct rb_node *n;
461 struct btrfs_qgroup *qgroup;
462
463 while ((n = rb_first(&fs_info->qgroup_tree))) {
464 qgroup = rb_entry(n, struct btrfs_qgroup, node);
465 rb_erase(n, &fs_info->qgroup_tree);
466 __del_qgroup_rb(qgroup);
467 }
468 /*
469 * we call btrfs_free_qgroup_config() when umounting
470 * filesystem and disabling quota, so we set qgroup_ulit
471 * to be null here to avoid double free.
472 */
473 ulist_free(fs_info->qgroup_ulist);
474 fs_info->qgroup_ulist = NULL;
475 }
476
477 static int add_qgroup_relation_item(struct btrfs_trans_handle *trans,
478 struct btrfs_root *quota_root,
479 u64 src, u64 dst)
480 {
481 int ret;
482 struct btrfs_path *path;
483 struct btrfs_key key;
484
485 path = btrfs_alloc_path();
486 if (!path)
487 return -ENOMEM;
488
489 key.objectid = src;
490 key.type = BTRFS_QGROUP_RELATION_KEY;
491 key.offset = dst;
492
493 ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
494
495 btrfs_mark_buffer_dirty(path->nodes[0]);
496
497 btrfs_free_path(path);
498 return ret;
499 }
500
501 static int del_qgroup_relation_item(struct btrfs_trans_handle *trans,
502 struct btrfs_root *quota_root,
503 u64 src, u64 dst)
504 {
505 int ret;
506 struct btrfs_path *path;
507 struct btrfs_key key;
508
509 path = btrfs_alloc_path();
510 if (!path)
511 return -ENOMEM;
512
513 key.objectid = src;
514 key.type = BTRFS_QGROUP_RELATION_KEY;
515 key.offset = dst;
516
517 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
518 if (ret < 0)
519 goto out;
520
521 if (ret > 0) {
522 ret = -ENOENT;
523 goto out;
524 }
525
526 ret = btrfs_del_item(trans, quota_root, path);
527 out:
528 btrfs_free_path(path);
529 return ret;
530 }
531
532 static int add_qgroup_item(struct btrfs_trans_handle *trans,
533 struct btrfs_root *quota_root, u64 qgroupid)
534 {
535 int ret;
536 struct btrfs_path *path;
537 struct btrfs_qgroup_info_item *qgroup_info;
538 struct btrfs_qgroup_limit_item *qgroup_limit;
539 struct extent_buffer *leaf;
540 struct btrfs_key key;
541
542 if (btrfs_test_is_dummy_root(quota_root))
543 return 0;
544
545 path = btrfs_alloc_path();
546 if (!path)
547 return -ENOMEM;
548
549 key.objectid = 0;
550 key.type = BTRFS_QGROUP_INFO_KEY;
551 key.offset = qgroupid;
552
553 /*
554 * Avoid a transaction abort by catching -EEXIST here. In that
555 * case, we proceed by re-initializing the existing structure
556 * on disk.
557 */
558
559 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
560 sizeof(*qgroup_info));
561 if (ret && ret != -EEXIST)
562 goto out;
563
564 leaf = path->nodes[0];
565 qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
566 struct btrfs_qgroup_info_item);
567 btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
568 btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
569 btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
570 btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
571 btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
572
573 btrfs_mark_buffer_dirty(leaf);
574
575 btrfs_release_path(path);
576
577 key.type = BTRFS_QGROUP_LIMIT_KEY;
578 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
579 sizeof(*qgroup_limit));
580 if (ret && ret != -EEXIST)
581 goto out;
582
583 leaf = path->nodes[0];
584 qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
585 struct btrfs_qgroup_limit_item);
586 btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
587 btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
588 btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
589 btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
590 btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
591
592 btrfs_mark_buffer_dirty(leaf);
593
594 ret = 0;
595 out:
596 btrfs_free_path(path);
597 return ret;
598 }
599
600 static int del_qgroup_item(struct btrfs_trans_handle *trans,
601 struct btrfs_root *quota_root, u64 qgroupid)
602 {
603 int ret;
604 struct btrfs_path *path;
605 struct btrfs_key key;
606
607 path = btrfs_alloc_path();
608 if (!path)
609 return -ENOMEM;
610
611 key.objectid = 0;
612 key.type = BTRFS_QGROUP_INFO_KEY;
613 key.offset = qgroupid;
614 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
615 if (ret < 0)
616 goto out;
617
618 if (ret > 0) {
619 ret = -ENOENT;
620 goto out;
621 }
622
623 ret = btrfs_del_item(trans, quota_root, path);
624 if (ret)
625 goto out;
626
627 btrfs_release_path(path);
628
629 key.type = BTRFS_QGROUP_LIMIT_KEY;
630 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
631 if (ret < 0)
632 goto out;
633
634 if (ret > 0) {
635 ret = -ENOENT;
636 goto out;
637 }
638
639 ret = btrfs_del_item(trans, quota_root, path);
640
641 out:
642 btrfs_free_path(path);
643 return ret;
644 }
645
646 static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
647 struct btrfs_root *root, u64 qgroupid,
648 u64 flags, u64 max_rfer, u64 max_excl,
649 u64 rsv_rfer, u64 rsv_excl)
650 {
651 struct btrfs_path *path;
652 struct btrfs_key key;
653 struct extent_buffer *l;
654 struct btrfs_qgroup_limit_item *qgroup_limit;
655 int ret;
656 int slot;
657
658 key.objectid = 0;
659 key.type = BTRFS_QGROUP_LIMIT_KEY;
660 key.offset = qgroupid;
661
662 path = btrfs_alloc_path();
663 if (!path)
664 return -ENOMEM;
665
666 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
667 if (ret > 0)
668 ret = -ENOENT;
669
670 if (ret)
671 goto out;
672
673 l = path->nodes[0];
674 slot = path->slots[0];
675 qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
676 btrfs_set_qgroup_limit_flags(l, qgroup_limit, flags);
677 btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, max_rfer);
678 btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, max_excl);
679 btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, rsv_rfer);
680 btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, rsv_excl);
681
682 btrfs_mark_buffer_dirty(l);
683
684 out:
685 btrfs_free_path(path);
686 return ret;
687 }
688
689 static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
690 struct btrfs_root *root,
691 struct btrfs_qgroup *qgroup)
692 {
693 struct btrfs_path *path;
694 struct btrfs_key key;
695 struct extent_buffer *l;
696 struct btrfs_qgroup_info_item *qgroup_info;
697 int ret;
698 int slot;
699
700 if (btrfs_test_is_dummy_root(root))
701 return 0;
702
703 key.objectid = 0;
704 key.type = BTRFS_QGROUP_INFO_KEY;
705 key.offset = qgroup->qgroupid;
706
707 path = btrfs_alloc_path();
708 if (!path)
709 return -ENOMEM;
710
711 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
712 if (ret > 0)
713 ret = -ENOENT;
714
715 if (ret)
716 goto out;
717
718 l = path->nodes[0];
719 slot = path->slots[0];
720 qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
721 btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
722 btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
723 btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
724 btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
725 btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
726
727 btrfs_mark_buffer_dirty(l);
728
729 out:
730 btrfs_free_path(path);
731 return ret;
732 }
733
734 static int update_qgroup_status_item(struct btrfs_trans_handle *trans,
735 struct btrfs_fs_info *fs_info,
736 struct btrfs_root *root)
737 {
738 struct btrfs_path *path;
739 struct btrfs_key key;
740 struct extent_buffer *l;
741 struct btrfs_qgroup_status_item *ptr;
742 int ret;
743 int slot;
744
745 key.objectid = 0;
746 key.type = BTRFS_QGROUP_STATUS_KEY;
747 key.offset = 0;
748
749 path = btrfs_alloc_path();
750 if (!path)
751 return -ENOMEM;
752
753 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
754 if (ret > 0)
755 ret = -ENOENT;
756
757 if (ret)
758 goto out;
759
760 l = path->nodes[0];
761 slot = path->slots[0];
762 ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
763 btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
764 btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
765 btrfs_set_qgroup_status_rescan(l, ptr,
766 fs_info->qgroup_rescan_progress.objectid);
767
768 btrfs_mark_buffer_dirty(l);
769
770 out:
771 btrfs_free_path(path);
772 return ret;
773 }
774
775 /*
776 * called with qgroup_lock held
777 */
778 static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
779 struct btrfs_root *root)
780 {
781 struct btrfs_path *path;
782 struct btrfs_key key;
783 struct extent_buffer *leaf = NULL;
784 int ret;
785 int nr = 0;
786
787 path = btrfs_alloc_path();
788 if (!path)
789 return -ENOMEM;
790
791 path->leave_spinning = 1;
792
793 key.objectid = 0;
794 key.offset = 0;
795 key.type = 0;
796
797 while (1) {
798 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
799 if (ret < 0)
800 goto out;
801 leaf = path->nodes[0];
802 nr = btrfs_header_nritems(leaf);
803 if (!nr)
804 break;
805 /*
806 * delete the leaf one by one
807 * since the whole tree is going
808 * to be deleted.
809 */
810 path->slots[0] = 0;
811 ret = btrfs_del_items(trans, root, path, 0, nr);
812 if (ret)
813 goto out;
814
815 btrfs_release_path(path);
816 }
817 ret = 0;
818 out:
819 root->fs_info->pending_quota_state = 0;
820 btrfs_free_path(path);
821 return ret;
822 }
823
824 int btrfs_quota_enable(struct btrfs_trans_handle *trans,
825 struct btrfs_fs_info *fs_info)
826 {
827 struct btrfs_root *quota_root;
828 struct btrfs_root *tree_root = fs_info->tree_root;
829 struct btrfs_path *path = NULL;
830 struct btrfs_qgroup_status_item *ptr;
831 struct extent_buffer *leaf;
832 struct btrfs_key key;
833 struct btrfs_key found_key;
834 struct btrfs_qgroup *qgroup = NULL;
835 int ret = 0;
836 int slot;
837
838 mutex_lock(&fs_info->qgroup_ioctl_lock);
839 if (fs_info->quota_root) {
840 fs_info->pending_quota_state = 1;
841 goto out;
842 }
843
844 fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
845 if (!fs_info->qgroup_ulist) {
846 ret = -ENOMEM;
847 goto out;
848 }
849
850 /*
851 * initially create the quota tree
852 */
853 quota_root = btrfs_create_tree(trans, fs_info,
854 BTRFS_QUOTA_TREE_OBJECTID);
855 if (IS_ERR(quota_root)) {
856 ret = PTR_ERR(quota_root);
857 goto out;
858 }
859
860 path = btrfs_alloc_path();
861 if (!path) {
862 ret = -ENOMEM;
863 goto out_free_root;
864 }
865
866 key.objectid = 0;
867 key.type = BTRFS_QGROUP_STATUS_KEY;
868 key.offset = 0;
869
870 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
871 sizeof(*ptr));
872 if (ret)
873 goto out_free_path;
874
875 leaf = path->nodes[0];
876 ptr = btrfs_item_ptr(leaf, path->slots[0],
877 struct btrfs_qgroup_status_item);
878 btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
879 btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
880 fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
881 BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
882 btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
883 btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
884
885 btrfs_mark_buffer_dirty(leaf);
886
887 key.objectid = 0;
888 key.type = BTRFS_ROOT_REF_KEY;
889 key.offset = 0;
890
891 btrfs_release_path(path);
892 ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
893 if (ret > 0)
894 goto out_add_root;
895 if (ret < 0)
896 goto out_free_path;
897
898
899 while (1) {
900 slot = path->slots[0];
901 leaf = path->nodes[0];
902 btrfs_item_key_to_cpu(leaf, &found_key, slot);
903
904 if (found_key.type == BTRFS_ROOT_REF_KEY) {
905 ret = add_qgroup_item(trans, quota_root,
906 found_key.offset);
907 if (ret)
908 goto out_free_path;
909
910 qgroup = add_qgroup_rb(fs_info, found_key.offset);
911 if (IS_ERR(qgroup)) {
912 ret = PTR_ERR(qgroup);
913 goto out_free_path;
914 }
915 }
916 ret = btrfs_next_item(tree_root, path);
917 if (ret < 0)
918 goto out_free_path;
919 if (ret)
920 break;
921 }
922
923 out_add_root:
924 btrfs_release_path(path);
925 ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
926 if (ret)
927 goto out_free_path;
928
929 qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
930 if (IS_ERR(qgroup)) {
931 ret = PTR_ERR(qgroup);
932 goto out_free_path;
933 }
934 spin_lock(&fs_info->qgroup_lock);
935 fs_info->quota_root = quota_root;
936 fs_info->pending_quota_state = 1;
937 spin_unlock(&fs_info->qgroup_lock);
938 out_free_path:
939 btrfs_free_path(path);
940 out_free_root:
941 if (ret) {
942 free_extent_buffer(quota_root->node);
943 free_extent_buffer(quota_root->commit_root);
944 kfree(quota_root);
945 }
946 out:
947 if (ret) {
948 ulist_free(fs_info->qgroup_ulist);
949 fs_info->qgroup_ulist = NULL;
950 }
951 mutex_unlock(&fs_info->qgroup_ioctl_lock);
952 return ret;
953 }
954
955 int btrfs_quota_disable(struct btrfs_trans_handle *trans,
956 struct btrfs_fs_info *fs_info)
957 {
958 struct btrfs_root *tree_root = fs_info->tree_root;
959 struct btrfs_root *quota_root;
960 int ret = 0;
961
962 mutex_lock(&fs_info->qgroup_ioctl_lock);
963 if (!fs_info->quota_root)
964 goto out;
965 spin_lock(&fs_info->qgroup_lock);
966 fs_info->quota_enabled = 0;
967 fs_info->pending_quota_state = 0;
968 quota_root = fs_info->quota_root;
969 fs_info->quota_root = NULL;
970 spin_unlock(&fs_info->qgroup_lock);
971
972 btrfs_free_qgroup_config(fs_info);
973
974 ret = btrfs_clean_quota_tree(trans, quota_root);
975 if (ret)
976 goto out;
977
978 ret = btrfs_del_root(trans, tree_root, &quota_root->root_key);
979 if (ret)
980 goto out;
981
982 list_del(&quota_root->dirty_list);
983
984 btrfs_tree_lock(quota_root->node);
985 clean_tree_block(trans, tree_root->fs_info, quota_root->node);
986 btrfs_tree_unlock(quota_root->node);
987 btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
988
989 free_extent_buffer(quota_root->node);
990 free_extent_buffer(quota_root->commit_root);
991 kfree(quota_root);
992 out:
993 mutex_unlock(&fs_info->qgroup_ioctl_lock);
994 return ret;
995 }
996
997 static void qgroup_dirty(struct btrfs_fs_info *fs_info,
998 struct btrfs_qgroup *qgroup)
999 {
1000 if (list_empty(&qgroup->dirty))
1001 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1002 }
1003
1004 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
1005 struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1006 {
1007 struct btrfs_root *quota_root;
1008 struct btrfs_qgroup *parent;
1009 struct btrfs_qgroup *member;
1010 struct btrfs_qgroup_list *list;
1011 int ret = 0;
1012
1013 mutex_lock(&fs_info->qgroup_ioctl_lock);
1014 quota_root = fs_info->quota_root;
1015 if (!quota_root) {
1016 ret = -EINVAL;
1017 goto out;
1018 }
1019 member = find_qgroup_rb(fs_info, src);
1020 parent = find_qgroup_rb(fs_info, dst);
1021 if (!member || !parent) {
1022 ret = -EINVAL;
1023 goto out;
1024 }
1025
1026 /* check if such qgroup relation exist firstly */
1027 list_for_each_entry(list, &member->groups, next_group) {
1028 if (list->group == parent) {
1029 ret = -EEXIST;
1030 goto out;
1031 }
1032 }
1033
1034 ret = add_qgroup_relation_item(trans, quota_root, src, dst);
1035 if (ret)
1036 goto out;
1037
1038 ret = add_qgroup_relation_item(trans, quota_root, dst, src);
1039 if (ret) {
1040 del_qgroup_relation_item(trans, quota_root, src, dst);
1041 goto out;
1042 }
1043
1044 spin_lock(&fs_info->qgroup_lock);
1045 ret = add_relation_rb(quota_root->fs_info, src, dst);
1046 spin_unlock(&fs_info->qgroup_lock);
1047 out:
1048 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1049 return ret;
1050 }
1051
1052 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
1053 struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1054 {
1055 struct btrfs_root *quota_root;
1056 struct btrfs_qgroup *parent;
1057 struct btrfs_qgroup *member;
1058 struct btrfs_qgroup_list *list;
1059 int ret = 0;
1060 int err;
1061
1062 mutex_lock(&fs_info->qgroup_ioctl_lock);
1063 quota_root = fs_info->quota_root;
1064 if (!quota_root) {
1065 ret = -EINVAL;
1066 goto out;
1067 }
1068
1069 member = find_qgroup_rb(fs_info, src);
1070 parent = find_qgroup_rb(fs_info, dst);
1071 if (!member || !parent) {
1072 ret = -EINVAL;
1073 goto out;
1074 }
1075
1076 /* check if such qgroup relation exist firstly */
1077 list_for_each_entry(list, &member->groups, next_group) {
1078 if (list->group == parent)
1079 goto exist;
1080 }
1081 ret = -ENOENT;
1082 goto out;
1083 exist:
1084 ret = del_qgroup_relation_item(trans, quota_root, src, dst);
1085 err = del_qgroup_relation_item(trans, quota_root, dst, src);
1086 if (err && !ret)
1087 ret = err;
1088
1089 spin_lock(&fs_info->qgroup_lock);
1090 del_relation_rb(fs_info, src, dst);
1091 spin_unlock(&fs_info->qgroup_lock);
1092 out:
1093 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1094 return ret;
1095 }
1096
1097 int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
1098 struct btrfs_fs_info *fs_info, u64 qgroupid, char *name)
1099 {
1100 struct btrfs_root *quota_root;
1101 struct btrfs_qgroup *qgroup;
1102 int ret = 0;
1103
1104 mutex_lock(&fs_info->qgroup_ioctl_lock);
1105 quota_root = fs_info->quota_root;
1106 if (!quota_root) {
1107 ret = -EINVAL;
1108 goto out;
1109 }
1110 qgroup = find_qgroup_rb(fs_info, qgroupid);
1111 if (qgroup) {
1112 ret = -EEXIST;
1113 goto out;
1114 }
1115
1116 ret = add_qgroup_item(trans, quota_root, qgroupid);
1117 if (ret)
1118 goto out;
1119
1120 spin_lock(&fs_info->qgroup_lock);
1121 qgroup = add_qgroup_rb(fs_info, qgroupid);
1122 spin_unlock(&fs_info->qgroup_lock);
1123
1124 if (IS_ERR(qgroup))
1125 ret = PTR_ERR(qgroup);
1126 out:
1127 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1128 return ret;
1129 }
1130
1131 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
1132 struct btrfs_fs_info *fs_info, u64 qgroupid)
1133 {
1134 struct btrfs_root *quota_root;
1135 struct btrfs_qgroup *qgroup;
1136 int ret = 0;
1137
1138 mutex_lock(&fs_info->qgroup_ioctl_lock);
1139 quota_root = fs_info->quota_root;
1140 if (!quota_root) {
1141 ret = -EINVAL;
1142 goto out;
1143 }
1144
1145 qgroup = find_qgroup_rb(fs_info, qgroupid);
1146 if (!qgroup) {
1147 ret = -ENOENT;
1148 goto out;
1149 } else {
1150 /* check if there are no relations to this qgroup */
1151 if (!list_empty(&qgroup->groups) ||
1152 !list_empty(&qgroup->members)) {
1153 ret = -EBUSY;
1154 goto out;
1155 }
1156 }
1157 ret = del_qgroup_item(trans, quota_root, qgroupid);
1158
1159 spin_lock(&fs_info->qgroup_lock);
1160 del_qgroup_rb(quota_root->fs_info, qgroupid);
1161 spin_unlock(&fs_info->qgroup_lock);
1162 out:
1163 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1164 return ret;
1165 }
1166
1167 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
1168 struct btrfs_fs_info *fs_info, u64 qgroupid,
1169 struct btrfs_qgroup_limit *limit)
1170 {
1171 struct btrfs_root *quota_root;
1172 struct btrfs_qgroup *qgroup;
1173 int ret = 0;
1174
1175 mutex_lock(&fs_info->qgroup_ioctl_lock);
1176 quota_root = fs_info->quota_root;
1177 if (!quota_root) {
1178 ret = -EINVAL;
1179 goto out;
1180 }
1181
1182 qgroup = find_qgroup_rb(fs_info, qgroupid);
1183 if (!qgroup) {
1184 ret = -ENOENT;
1185 goto out;
1186 }
1187 ret = update_qgroup_limit_item(trans, quota_root, qgroupid,
1188 limit->flags, limit->max_rfer,
1189 limit->max_excl, limit->rsv_rfer,
1190 limit->rsv_excl);
1191 if (ret) {
1192 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1193 btrfs_info(fs_info, "unable to update quota limit for %llu",
1194 qgroupid);
1195 }
1196
1197 spin_lock(&fs_info->qgroup_lock);
1198 qgroup->lim_flags = limit->flags;
1199 qgroup->max_rfer = limit->max_rfer;
1200 qgroup->max_excl = limit->max_excl;
1201 qgroup->rsv_rfer = limit->rsv_rfer;
1202 qgroup->rsv_excl = limit->rsv_excl;
1203 spin_unlock(&fs_info->qgroup_lock);
1204 out:
1205 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1206 return ret;
1207 }
1208
1209 static int comp_oper_exist(struct btrfs_qgroup_operation *oper1,
1210 struct btrfs_qgroup_operation *oper2)
1211 {
1212 /*
1213 * Ignore seq and type here, we're looking for any operation
1214 * at all related to this extent on that root.
1215 */
1216 if (oper1->bytenr < oper2->bytenr)
1217 return -1;
1218 if (oper1->bytenr > oper2->bytenr)
1219 return 1;
1220 if (oper1->ref_root < oper2->ref_root)
1221 return -1;
1222 if (oper1->ref_root > oper2->ref_root)
1223 return 1;
1224 return 0;
1225 }
1226
1227 static int qgroup_oper_exists(struct btrfs_fs_info *fs_info,
1228 struct btrfs_qgroup_operation *oper)
1229 {
1230 struct rb_node *n;
1231 struct btrfs_qgroup_operation *cur;
1232 int cmp;
1233
1234 spin_lock(&fs_info->qgroup_op_lock);
1235 n = fs_info->qgroup_op_tree.rb_node;
1236 while (n) {
1237 cur = rb_entry(n, struct btrfs_qgroup_operation, n);
1238 cmp = comp_oper_exist(cur, oper);
1239 if (cmp < 0) {
1240 n = n->rb_right;
1241 } else if (cmp) {
1242 n = n->rb_left;
1243 } else {
1244 spin_unlock(&fs_info->qgroup_op_lock);
1245 return -EEXIST;
1246 }
1247 }
1248 spin_unlock(&fs_info->qgroup_op_lock);
1249 return 0;
1250 }
1251
1252 static int comp_oper(struct btrfs_qgroup_operation *oper1,
1253 struct btrfs_qgroup_operation *oper2)
1254 {
1255 if (oper1->bytenr < oper2->bytenr)
1256 return -1;
1257 if (oper1->bytenr > oper2->bytenr)
1258 return 1;
1259 if (oper1->ref_root < oper2->ref_root)
1260 return -1;
1261 if (oper1->ref_root > oper2->ref_root)
1262 return 1;
1263 if (oper1->seq < oper2->seq)
1264 return -1;
1265 if (oper1->seq > oper2->seq)
1266 return 1;
1267 if (oper1->type < oper2->type)
1268 return -1;
1269 if (oper1->type > oper2->type)
1270 return 1;
1271 return 0;
1272 }
1273
1274 static int insert_qgroup_oper(struct btrfs_fs_info *fs_info,
1275 struct btrfs_qgroup_operation *oper)
1276 {
1277 struct rb_node **p;
1278 struct rb_node *parent = NULL;
1279 struct btrfs_qgroup_operation *cur;
1280 int cmp;
1281
1282 spin_lock(&fs_info->qgroup_op_lock);
1283 p = &fs_info->qgroup_op_tree.rb_node;
1284 while (*p) {
1285 parent = *p;
1286 cur = rb_entry(parent, struct btrfs_qgroup_operation, n);
1287 cmp = comp_oper(cur, oper);
1288 if (cmp < 0) {
1289 p = &(*p)->rb_right;
1290 } else if (cmp) {
1291 p = &(*p)->rb_left;
1292 } else {
1293 spin_unlock(&fs_info->qgroup_op_lock);
1294 return -EEXIST;
1295 }
1296 }
1297 rb_link_node(&oper->n, parent, p);
1298 rb_insert_color(&oper->n, &fs_info->qgroup_op_tree);
1299 spin_unlock(&fs_info->qgroup_op_lock);
1300 return 0;
1301 }
1302
1303 /*
1304 * Record a quota operation for processing later on.
1305 * @trans: the transaction we are adding the delayed op to.
1306 * @fs_info: the fs_info for this fs.
1307 * @ref_root: the root of the reference we are acting on,
1308 * @bytenr: the bytenr we are acting on.
1309 * @num_bytes: the number of bytes in the reference.
1310 * @type: the type of operation this is.
1311 * @mod_seq: do we need to get a sequence number for looking up roots.
1312 *
1313 * We just add it to our trans qgroup_ref_list and carry on and process these
1314 * operations in order at some later point. If the reference root isn't a fs
1315 * root then we don't bother with doing anything.
1316 *
1317 * MUST BE HOLDING THE REF LOCK.
1318 */
1319 int btrfs_qgroup_record_ref(struct btrfs_trans_handle *trans,
1320 struct btrfs_fs_info *fs_info, u64 ref_root,
1321 u64 bytenr, u64 num_bytes,
1322 enum btrfs_qgroup_operation_type type, int mod_seq)
1323 {
1324 struct btrfs_qgroup_operation *oper;
1325 int ret;
1326
1327 if (!is_fstree(ref_root) || !fs_info->quota_enabled)
1328 return 0;
1329
1330 oper = kmalloc(sizeof(*oper), GFP_NOFS);
1331 if (!oper)
1332 return -ENOMEM;
1333
1334 oper->ref_root = ref_root;
1335 oper->bytenr = bytenr;
1336 oper->num_bytes = num_bytes;
1337 oper->type = type;
1338 oper->seq = atomic_inc_return(&fs_info->qgroup_op_seq);
1339 INIT_LIST_HEAD(&oper->elem.list);
1340 oper->elem.seq = 0;
1341
1342 trace_btrfs_qgroup_record_ref(oper);
1343
1344 if (type == BTRFS_QGROUP_OPER_SUB_SUBTREE) {
1345 /*
1346 * If any operation for this bytenr/ref_root combo
1347 * exists, then we know it's not exclusively owned and
1348 * shouldn't be queued up.
1349 *
1350 * This also catches the case where we have a cloned
1351 * extent that gets queued up multiple times during
1352 * drop snapshot.
1353 */
1354 if (qgroup_oper_exists(fs_info, oper)) {
1355 kfree(oper);
1356 return 0;
1357 }
1358 }
1359
1360 ret = insert_qgroup_oper(fs_info, oper);
1361 if (ret) {
1362 /* Shouldn't happen so have an assert for developers */
1363 ASSERT(0);
1364 kfree(oper);
1365 return ret;
1366 }
1367 list_add_tail(&oper->list, &trans->qgroup_ref_list);
1368
1369 if (mod_seq)
1370 btrfs_get_tree_mod_seq(fs_info, &oper->elem);
1371
1372 return 0;
1373 }
1374
1375 /*
1376 * The easy accounting, if we are adding/removing the only ref for an extent
1377 * then this qgroup and all of the parent qgroups get their refrence and
1378 * exclusive counts adjusted.
1379 */
1380 static int qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1381 struct btrfs_qgroup_operation *oper)
1382 {
1383 struct btrfs_qgroup *qgroup;
1384 struct ulist *tmp;
1385 struct btrfs_qgroup_list *glist;
1386 struct ulist_node *unode;
1387 struct ulist_iterator uiter;
1388 int sign = 0;
1389 int ret = 0;
1390
1391 tmp = ulist_alloc(GFP_NOFS);
1392 if (!tmp)
1393 return -ENOMEM;
1394
1395 spin_lock(&fs_info->qgroup_lock);
1396 if (!fs_info->quota_root)
1397 goto out;
1398 qgroup = find_qgroup_rb(fs_info, oper->ref_root);
1399 if (!qgroup)
1400 goto out;
1401 switch (oper->type) {
1402 case BTRFS_QGROUP_OPER_ADD_EXCL:
1403 sign = 1;
1404 break;
1405 case BTRFS_QGROUP_OPER_SUB_EXCL:
1406 sign = -1;
1407 break;
1408 default:
1409 ASSERT(0);
1410 }
1411 qgroup->rfer += sign * oper->num_bytes;
1412 qgroup->rfer_cmpr += sign * oper->num_bytes;
1413
1414 WARN_ON(sign < 0 && qgroup->excl < oper->num_bytes);
1415 qgroup->excl += sign * oper->num_bytes;
1416 qgroup->excl_cmpr += sign * oper->num_bytes;
1417
1418 qgroup_dirty(fs_info, qgroup);
1419
1420 /* Get all of the parent groups that contain this qgroup */
1421 list_for_each_entry(glist, &qgroup->groups, next_group) {
1422 ret = ulist_add(tmp, glist->group->qgroupid,
1423 ptr_to_u64(glist->group), GFP_ATOMIC);
1424 if (ret < 0)
1425 goto out;
1426 }
1427
1428 /* Iterate all of the parents and adjust their reference counts */
1429 ULIST_ITER_INIT(&uiter);
1430 while ((unode = ulist_next(tmp, &uiter))) {
1431 qgroup = u64_to_ptr(unode->aux);
1432 qgroup->rfer += sign * oper->num_bytes;
1433 qgroup->rfer_cmpr += sign * oper->num_bytes;
1434 WARN_ON(sign < 0 && qgroup->excl < oper->num_bytes);
1435 qgroup->excl += sign * oper->num_bytes;
1436 qgroup->excl_cmpr += sign * oper->num_bytes;
1437 qgroup_dirty(fs_info, qgroup);
1438
1439 /* Add any parents of the parents */
1440 list_for_each_entry(glist, &qgroup->groups, next_group) {
1441 ret = ulist_add(tmp, glist->group->qgroupid,
1442 ptr_to_u64(glist->group), GFP_ATOMIC);
1443 if (ret < 0)
1444 goto out;
1445 }
1446 }
1447 ret = 0;
1448 out:
1449 spin_unlock(&fs_info->qgroup_lock);
1450 ulist_free(tmp);
1451 return ret;
1452 }
1453
1454 /*
1455 * Walk all of the roots that pointed to our bytenr and adjust their refcnts as
1456 * properly.
1457 */
1458 static int qgroup_calc_old_refcnt(struct btrfs_fs_info *fs_info,
1459 u64 root_to_skip, struct ulist *tmp,
1460 struct ulist *roots, struct ulist *qgroups,
1461 u64 seq, int *old_roots, int rescan)
1462 {
1463 struct ulist_node *unode;
1464 struct ulist_iterator uiter;
1465 struct ulist_node *tmp_unode;
1466 struct ulist_iterator tmp_uiter;
1467 struct btrfs_qgroup *qg;
1468 int ret;
1469
1470 ULIST_ITER_INIT(&uiter);
1471 while ((unode = ulist_next(roots, &uiter))) {
1472 /* We don't count our current root here */
1473 if (unode->val == root_to_skip)
1474 continue;
1475 qg = find_qgroup_rb(fs_info, unode->val);
1476 if (!qg)
1477 continue;
1478 /*
1479 * We could have a pending removal of this same ref so we may
1480 * not have actually found our ref root when doing
1481 * btrfs_find_all_roots, so we need to keep track of how many
1482 * old roots we find in case we removed ours and added a
1483 * different one at the same time. I don't think this could
1484 * happen in practice but that sort of thinking leads to pain
1485 * and suffering and to the dark side.
1486 */
1487 (*old_roots)++;
1488
1489 ulist_reinit(tmp);
1490 ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
1491 GFP_ATOMIC);
1492 if (ret < 0)
1493 return ret;
1494 ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
1495 if (ret < 0)
1496 return ret;
1497 ULIST_ITER_INIT(&tmp_uiter);
1498 while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
1499 struct btrfs_qgroup_list *glist;
1500
1501 qg = u64_to_ptr(tmp_unode->aux);
1502 /*
1503 * We use this sequence number to keep from having to
1504 * run the whole list and 0 out the refcnt every time.
1505 * We basically use sequnce as the known 0 count and
1506 * then add 1 everytime we see a qgroup. This is how we
1507 * get how many of the roots actually point up to the
1508 * upper level qgroups in order to determine exclusive
1509 * counts.
1510 *
1511 * For rescan we want to set old_refcnt to seq so our
1512 * exclusive calculations end up correct.
1513 */
1514 if (rescan)
1515 qg->old_refcnt = seq;
1516 else if (qg->old_refcnt < seq)
1517 qg->old_refcnt = seq + 1;
1518 else
1519 qg->old_refcnt++;
1520
1521 if (qg->new_refcnt < seq)
1522 qg->new_refcnt = seq + 1;
1523 else
1524 qg->new_refcnt++;
1525 list_for_each_entry(glist, &qg->groups, next_group) {
1526 ret = ulist_add(qgroups, glist->group->qgroupid,
1527 ptr_to_u64(glist->group),
1528 GFP_ATOMIC);
1529 if (ret < 0)
1530 return ret;
1531 ret = ulist_add(tmp, glist->group->qgroupid,
1532 ptr_to_u64(glist->group),
1533 GFP_ATOMIC);
1534 if (ret < 0)
1535 return ret;
1536 }
1537 }
1538 }
1539 return 0;
1540 }
1541
1542 /*
1543 * We need to walk forward in our operation tree and account for any roots that
1544 * were deleted after we made this operation.
1545 */
1546 static int qgroup_account_deleted_refs(struct btrfs_fs_info *fs_info,
1547 struct btrfs_qgroup_operation *oper,
1548 struct ulist *tmp,
1549 struct ulist *qgroups, u64 seq,
1550 int *old_roots)
1551 {
1552 struct ulist_node *unode;
1553 struct ulist_iterator uiter;
1554 struct btrfs_qgroup *qg;
1555 struct btrfs_qgroup_operation *tmp_oper;
1556 struct rb_node *n;
1557 int ret;
1558
1559 ulist_reinit(tmp);
1560
1561 /*
1562 * We only walk forward in the tree since we're only interested in
1563 * removals that happened _after_ our operation.
1564 */
1565 spin_lock(&fs_info->qgroup_op_lock);
1566 n = rb_next(&oper->n);
1567 spin_unlock(&fs_info->qgroup_op_lock);
1568 if (!n)
1569 return 0;
1570 tmp_oper = rb_entry(n, struct btrfs_qgroup_operation, n);
1571 while (tmp_oper->bytenr == oper->bytenr) {
1572 /*
1573 * If it's not a removal we don't care, additions work out
1574 * properly with our refcnt tracking.
1575 */
1576 if (tmp_oper->type != BTRFS_QGROUP_OPER_SUB_SHARED &&
1577 tmp_oper->type != BTRFS_QGROUP_OPER_SUB_EXCL)
1578 goto next;
1579 qg = find_qgroup_rb(fs_info, tmp_oper->ref_root);
1580 if (!qg)
1581 goto next;
1582 ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
1583 GFP_ATOMIC);
1584 if (ret) {
1585 if (ret < 0)
1586 return ret;
1587 /*
1588 * We only want to increase old_roots if this qgroup is
1589 * not already in the list of qgroups. If it is already
1590 * there then that means it must have been re-added or
1591 * the delete will be discarded because we had an
1592 * existing ref that we haven't looked up yet. In this
1593 * case we don't want to increase old_roots. So if ret
1594 * == 1 then we know that this is the first time we've
1595 * seen this qgroup and we can bump the old_roots.
1596 */
1597 (*old_roots)++;
1598 ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg),
1599 GFP_ATOMIC);
1600 if (ret < 0)
1601 return ret;
1602 }
1603 next:
1604 spin_lock(&fs_info->qgroup_op_lock);
1605 n = rb_next(&tmp_oper->n);
1606 spin_unlock(&fs_info->qgroup_op_lock);
1607 if (!n)
1608 break;
1609 tmp_oper = rb_entry(n, struct btrfs_qgroup_operation, n);
1610 }
1611
1612 /* Ok now process the qgroups we found */
1613 ULIST_ITER_INIT(&uiter);
1614 while ((unode = ulist_next(tmp, &uiter))) {
1615 struct btrfs_qgroup_list *glist;
1616
1617 qg = u64_to_ptr(unode->aux);
1618 if (qg->old_refcnt < seq)
1619 qg->old_refcnt = seq + 1;
1620 else
1621 qg->old_refcnt++;
1622 if (qg->new_refcnt < seq)
1623 qg->new_refcnt = seq + 1;
1624 else
1625 qg->new_refcnt++;
1626 list_for_each_entry(glist, &qg->groups, next_group) {
1627 ret = ulist_add(qgroups, glist->group->qgroupid,
1628 ptr_to_u64(glist->group), GFP_ATOMIC);
1629 if (ret < 0)
1630 return ret;
1631 ret = ulist_add(tmp, glist->group->qgroupid,
1632 ptr_to_u64(glist->group), GFP_ATOMIC);
1633 if (ret < 0)
1634 return ret;
1635 }
1636 }
1637 return 0;
1638 }
1639
1640 /* Add refcnt for the newly added reference. */
1641 static int qgroup_calc_new_refcnt(struct btrfs_fs_info *fs_info,
1642 struct btrfs_qgroup_operation *oper,
1643 struct btrfs_qgroup *qgroup,
1644 struct ulist *tmp, struct ulist *qgroups,
1645 u64 seq)
1646 {
1647 struct ulist_node *unode;
1648 struct ulist_iterator uiter;
1649 struct btrfs_qgroup *qg;
1650 int ret;
1651
1652 ulist_reinit(tmp);
1653 ret = ulist_add(qgroups, qgroup->qgroupid, ptr_to_u64(qgroup),
1654 GFP_ATOMIC);
1655 if (ret < 0)
1656 return ret;
1657 ret = ulist_add(tmp, qgroup->qgroupid, ptr_to_u64(qgroup),
1658 GFP_ATOMIC);
1659 if (ret < 0)
1660 return ret;
1661 ULIST_ITER_INIT(&uiter);
1662 while ((unode = ulist_next(tmp, &uiter))) {
1663 struct btrfs_qgroup_list *glist;
1664
1665 qg = u64_to_ptr(unode->aux);
1666 if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED) {
1667 if (qg->new_refcnt < seq)
1668 qg->new_refcnt = seq + 1;
1669 else
1670 qg->new_refcnt++;
1671 } else {
1672 if (qg->old_refcnt < seq)
1673 qg->old_refcnt = seq + 1;
1674 else
1675 qg->old_refcnt++;
1676 }
1677 list_for_each_entry(glist, &qg->groups, next_group) {
1678 ret = ulist_add(tmp, glist->group->qgroupid,
1679 ptr_to_u64(glist->group), GFP_ATOMIC);
1680 if (ret < 0)
1681 return ret;
1682 ret = ulist_add(qgroups, glist->group->qgroupid,
1683 ptr_to_u64(glist->group), GFP_ATOMIC);
1684 if (ret < 0)
1685 return ret;
1686 }
1687 }
1688 return 0;
1689 }
1690
1691 /*
1692 * This adjusts the counters for all referenced qgroups if need be.
1693 */
1694 static int qgroup_adjust_counters(struct btrfs_fs_info *fs_info,
1695 u64 root_to_skip, u64 num_bytes,
1696 struct ulist *qgroups, u64 seq,
1697 int old_roots, int new_roots, int rescan)
1698 {
1699 struct ulist_node *unode;
1700 struct ulist_iterator uiter;
1701 struct btrfs_qgroup *qg;
1702 u64 cur_new_count, cur_old_count;
1703
1704 ULIST_ITER_INIT(&uiter);
1705 while ((unode = ulist_next(qgroups, &uiter))) {
1706 bool dirty = false;
1707
1708 qg = u64_to_ptr(unode->aux);
1709 /*
1710 * Wasn't referenced before but is now, add to the reference
1711 * counters.
1712 */
1713 if (qg->old_refcnt <= seq && qg->new_refcnt > seq) {
1714 qg->rfer += num_bytes;
1715 qg->rfer_cmpr += num_bytes;
1716 dirty = true;
1717 }
1718
1719 /*
1720 * Was referenced before but isn't now, subtract from the
1721 * reference counters.
1722 */
1723 if (qg->old_refcnt > seq && qg->new_refcnt <= seq) {
1724 qg->rfer -= num_bytes;
1725 qg->rfer_cmpr -= num_bytes;
1726 dirty = true;
1727 }
1728
1729 if (qg->old_refcnt < seq)
1730 cur_old_count = 0;
1731 else
1732 cur_old_count = qg->old_refcnt - seq;
1733 if (qg->new_refcnt < seq)
1734 cur_new_count = 0;
1735 else
1736 cur_new_count = qg->new_refcnt - seq;
1737
1738 /*
1739 * If our refcount was the same as the roots previously but our
1740 * new count isn't the same as the number of roots now then we
1741 * went from having a exclusive reference on this range to not.
1742 */
1743 if (old_roots && cur_old_count == old_roots &&
1744 (cur_new_count != new_roots || new_roots == 0)) {
1745 WARN_ON(cur_new_count != new_roots && new_roots == 0);
1746 qg->excl -= num_bytes;
1747 qg->excl_cmpr -= num_bytes;
1748 dirty = true;
1749 }
1750
1751 /*
1752 * If we didn't reference all the roots before but now we do we
1753 * have an exclusive reference to this range.
1754 */
1755 if ((!old_roots || (old_roots && cur_old_count != old_roots))
1756 && cur_new_count == new_roots) {
1757 qg->excl += num_bytes;
1758 qg->excl_cmpr += num_bytes;
1759 dirty = true;
1760 }
1761
1762 if (dirty)
1763 qgroup_dirty(fs_info, qg);
1764 }
1765 return 0;
1766 }
1767
1768 /*
1769 * If we removed a data extent and there were other references for that bytenr
1770 * then we need to lookup all referenced roots to make sure we still don't
1771 * reference this bytenr. If we do then we can just discard this operation.
1772 */
1773 static int check_existing_refs(struct btrfs_trans_handle *trans,
1774 struct btrfs_fs_info *fs_info,
1775 struct btrfs_qgroup_operation *oper)
1776 {
1777 struct ulist *roots = NULL;
1778 struct ulist_node *unode;
1779 struct ulist_iterator uiter;
1780 int ret = 0;
1781
1782 ret = btrfs_find_all_roots(trans, fs_info, oper->bytenr,
1783 oper->elem.seq, &roots);
1784 if (ret < 0)
1785 return ret;
1786 ret = 0;
1787
1788 ULIST_ITER_INIT(&uiter);
1789 while ((unode = ulist_next(roots, &uiter))) {
1790 if (unode->val == oper->ref_root) {
1791 ret = 1;
1792 break;
1793 }
1794 }
1795 ulist_free(roots);
1796 btrfs_put_tree_mod_seq(fs_info, &oper->elem);
1797
1798 return ret;
1799 }
1800
1801 /*
1802 * If we share a reference across multiple roots then we may need to adjust
1803 * various qgroups referenced and exclusive counters. The basic premise is this
1804 *
1805 * 1) We have seq to represent a 0 count. Instead of looping through all of the
1806 * qgroups and resetting their refcount to 0 we just constantly bump this
1807 * sequence number to act as the base reference count. This means that if
1808 * anybody is equal to or below this sequence they were never referenced. We
1809 * jack this sequence up by the number of roots we found each time in order to
1810 * make sure we don't have any overlap.
1811 *
1812 * 2) We first search all the roots that reference the area _except_ the root
1813 * we're acting on currently. This makes up the old_refcnt of all the qgroups
1814 * before.
1815 *
1816 * 3) We walk all of the qgroups referenced by the root we are currently acting
1817 * on, and will either adjust old_refcnt in the case of a removal or the
1818 * new_refcnt in the case of an addition.
1819 *
1820 * 4) Finally we walk all the qgroups that are referenced by this range
1821 * including the root we are acting on currently. We will adjust the counters
1822 * based on the number of roots we had and will have after this operation.
1823 *
1824 * Take this example as an illustration
1825 *
1826 * [qgroup 1/0]
1827 * / | \
1828 * [qg 0/0] [qg 0/1] [qg 0/2]
1829 * \ | /
1830 * [ extent ]
1831 *
1832 * Say we are adding a reference that is covered by qg 0/0. The first step
1833 * would give a refcnt of 1 to qg 0/1 and 0/2 and a refcnt of 2 to qg 1/0 with
1834 * old_roots being 2. Because it is adding new_roots will be 1. We then go
1835 * through qg 0/0 which will get the new_refcnt set to 1 and add 1 to qg 1/0's
1836 * new_refcnt, bringing it to 3. We then walk through all of the qgroups, we
1837 * notice that the old refcnt for qg 0/0 < the new refcnt, so we added a
1838 * reference and thus must add the size to the referenced bytes. Everything
1839 * else is the same so nothing else changes.
1840 */
1841 static int qgroup_shared_accounting(struct btrfs_trans_handle *trans,
1842 struct btrfs_fs_info *fs_info,
1843 struct btrfs_qgroup_operation *oper)
1844 {
1845 struct ulist *roots = NULL;
1846 struct ulist *qgroups, *tmp;
1847 struct btrfs_qgroup *qgroup;
1848 struct seq_list elem = SEQ_LIST_INIT(elem);
1849 u64 seq;
1850 int old_roots = 0;
1851 int new_roots = 0;
1852 int ret = 0;
1853
1854 if (oper->elem.seq) {
1855 ret = check_existing_refs(trans, fs_info, oper);
1856 if (ret < 0)
1857 return ret;
1858 if (ret)
1859 return 0;
1860 }
1861
1862 qgroups = ulist_alloc(GFP_NOFS);
1863 if (!qgroups)
1864 return -ENOMEM;
1865
1866 tmp = ulist_alloc(GFP_NOFS);
1867 if (!tmp) {
1868 ulist_free(qgroups);
1869 return -ENOMEM;
1870 }
1871
1872 btrfs_get_tree_mod_seq(fs_info, &elem);
1873 ret = btrfs_find_all_roots(trans, fs_info, oper->bytenr, elem.seq,
1874 &roots);
1875 btrfs_put_tree_mod_seq(fs_info, &elem);
1876 if (ret < 0) {
1877 ulist_free(qgroups);
1878 ulist_free(tmp);
1879 return ret;
1880 }
1881 spin_lock(&fs_info->qgroup_lock);
1882 qgroup = find_qgroup_rb(fs_info, oper->ref_root);
1883 if (!qgroup)
1884 goto out;
1885 seq = fs_info->qgroup_seq;
1886
1887 /*
1888 * So roots is the list of all the roots currently pointing at the
1889 * bytenr, including the ref we are adding if we are adding, or not if
1890 * we are removing a ref. So we pass in the ref_root to skip that root
1891 * in our calculations. We set old_refnct and new_refcnt cause who the
1892 * hell knows what everything looked like before, and it doesn't matter
1893 * except...
1894 */
1895 ret = qgroup_calc_old_refcnt(fs_info, oper->ref_root, tmp, roots, qgroups,
1896 seq, &old_roots, 0);
1897 if (ret < 0)
1898 goto out;
1899
1900 /*
1901 * Now adjust the refcounts of the qgroups that care about this
1902 * reference, either the old_count in the case of removal or new_count
1903 * in the case of an addition.
1904 */
1905 ret = qgroup_calc_new_refcnt(fs_info, oper, qgroup, tmp, qgroups,
1906 seq);
1907 if (ret < 0)
1908 goto out;
1909
1910 /*
1911 * ...in the case of removals. If we had a removal before we got around
1912 * to processing this operation then we need to find that guy and count
1913 * his references as if they really existed so we don't end up screwing
1914 * up the exclusive counts. Then whenever we go to process the delete
1915 * everything will be grand and we can account for whatever exclusive
1916 * changes need to be made there. We also have to pass in old_roots so
1917 * we have an accurate count of the roots as it pertains to this
1918 * operations view of the world.
1919 */
1920 ret = qgroup_account_deleted_refs(fs_info, oper, tmp, qgroups, seq,
1921 &old_roots);
1922 if (ret < 0)
1923 goto out;
1924
1925 /*
1926 * We are adding our root, need to adjust up the number of roots,
1927 * otherwise old_roots is the number of roots we want.
1928 */
1929 if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED) {
1930 new_roots = old_roots + 1;
1931 } else {
1932 new_roots = old_roots;
1933 old_roots++;
1934 }
1935 fs_info->qgroup_seq += old_roots + 1;
1936
1937
1938 /*
1939 * And now the magic happens, bless Arne for having a pretty elegant
1940 * solution for this.
1941 */
1942 qgroup_adjust_counters(fs_info, oper->ref_root, oper->num_bytes,
1943 qgroups, seq, old_roots, new_roots, 0);
1944 out:
1945 spin_unlock(&fs_info->qgroup_lock);
1946 ulist_free(qgroups);
1947 ulist_free(roots);
1948 ulist_free(tmp);
1949 return ret;
1950 }
1951
1952 /*
1953 * Process a reference to a shared subtree. This type of operation is
1954 * queued during snapshot removal when we encounter extents which are
1955 * shared between more than one root.
1956 */
1957 static int qgroup_subtree_accounting(struct btrfs_trans_handle *trans,
1958 struct btrfs_fs_info *fs_info,
1959 struct btrfs_qgroup_operation *oper)
1960 {
1961 struct ulist *roots = NULL;
1962 struct ulist_node *unode;
1963 struct ulist_iterator uiter;
1964 struct btrfs_qgroup_list *glist;
1965 struct ulist *parents;
1966 int ret = 0;
1967 int err;
1968 struct btrfs_qgroup *qg;
1969 u64 root_obj = 0;
1970 struct seq_list elem = SEQ_LIST_INIT(elem);
1971
1972 parents = ulist_alloc(GFP_NOFS);
1973 if (!parents)
1974 return -ENOMEM;
1975
1976 btrfs_get_tree_mod_seq(fs_info, &elem);
1977 ret = btrfs_find_all_roots(trans, fs_info, oper->bytenr,
1978 elem.seq, &roots);
1979 btrfs_put_tree_mod_seq(fs_info, &elem);
1980 if (ret < 0)
1981 goto out;
1982
1983 if (roots->nnodes != 1)
1984 goto out;
1985
1986 ULIST_ITER_INIT(&uiter);
1987 unode = ulist_next(roots, &uiter); /* Only want 1 so no need to loop */
1988 /*
1989 * If we find our ref root then that means all refs
1990 * this extent has to the root have not yet been
1991 * deleted. In that case, we do nothing and let the
1992 * last ref for this bytenr drive our update.
1993 *
1994 * This can happen for example if an extent is
1995 * referenced multiple times in a snapshot (clone,
1996 * etc). If we are in the middle of snapshot removal,
1997 * queued updates for such an extent will find the
1998 * root if we have not yet finished removing the
1999 * snapshot.
2000 */
2001 if (unode->val == oper->ref_root)
2002 goto out;
2003
2004 root_obj = unode->val;
2005 BUG_ON(!root_obj);
2006
2007 spin_lock(&fs_info->qgroup_lock);
2008 qg = find_qgroup_rb(fs_info, root_obj);
2009 if (!qg)
2010 goto out_unlock;
2011
2012 qg->excl += oper->num_bytes;
2013 qg->excl_cmpr += oper->num_bytes;
2014 qgroup_dirty(fs_info, qg);
2015
2016 /*
2017 * Adjust counts for parent groups. First we find all
2018 * parents, then in the 2nd loop we do the adjustment
2019 * while adding parents of the parents to our ulist.
2020 */
2021 list_for_each_entry(glist, &qg->groups, next_group) {
2022 err = ulist_add(parents, glist->group->qgroupid,
2023 ptr_to_u64(glist->group), GFP_ATOMIC);
2024 if (err < 0) {
2025 ret = err;
2026 goto out_unlock;
2027 }
2028 }
2029
2030 ULIST_ITER_INIT(&uiter);
2031 while ((unode = ulist_next(parents, &uiter))) {
2032 qg = u64_to_ptr(unode->aux);
2033 qg->excl += oper->num_bytes;
2034 qg->excl_cmpr += oper->num_bytes;
2035 qgroup_dirty(fs_info, qg);
2036
2037 /* Add any parents of the parents */
2038 list_for_each_entry(glist, &qg->groups, next_group) {
2039 err = ulist_add(parents, glist->group->qgroupid,
2040 ptr_to_u64(glist->group), GFP_ATOMIC);
2041 if (err < 0) {
2042 ret = err;
2043 goto out_unlock;
2044 }
2045 }
2046 }
2047
2048 out_unlock:
2049 spin_unlock(&fs_info->qgroup_lock);
2050
2051 out:
2052 ulist_free(roots);
2053 ulist_free(parents);
2054 return ret;
2055 }
2056
2057 /*
2058 * btrfs_qgroup_account_ref is called for every ref that is added to or deleted
2059 * from the fs. First, all roots referencing the extent are searched, and
2060 * then the space is accounted accordingly to the different roots. The
2061 * accounting algorithm works in 3 steps documented inline.
2062 */
2063 static int btrfs_qgroup_account(struct btrfs_trans_handle *trans,
2064 struct btrfs_fs_info *fs_info,
2065 struct btrfs_qgroup_operation *oper)
2066 {
2067 int ret = 0;
2068
2069 if (!fs_info->quota_enabled)
2070 return 0;
2071
2072 BUG_ON(!fs_info->quota_root);
2073
2074 mutex_lock(&fs_info->qgroup_rescan_lock);
2075 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2076 if (fs_info->qgroup_rescan_progress.objectid <= oper->bytenr) {
2077 mutex_unlock(&fs_info->qgroup_rescan_lock);
2078 return 0;
2079 }
2080 }
2081 mutex_unlock(&fs_info->qgroup_rescan_lock);
2082
2083 ASSERT(is_fstree(oper->ref_root));
2084
2085 trace_btrfs_qgroup_account(oper);
2086
2087 switch (oper->type) {
2088 case BTRFS_QGROUP_OPER_ADD_EXCL:
2089 case BTRFS_QGROUP_OPER_SUB_EXCL:
2090 ret = qgroup_excl_accounting(fs_info, oper);
2091 break;
2092 case BTRFS_QGROUP_OPER_ADD_SHARED:
2093 case BTRFS_QGROUP_OPER_SUB_SHARED:
2094 ret = qgroup_shared_accounting(trans, fs_info, oper);
2095 break;
2096 case BTRFS_QGROUP_OPER_SUB_SUBTREE:
2097 ret = qgroup_subtree_accounting(trans, fs_info, oper);
2098 break;
2099 default:
2100 ASSERT(0);
2101 }
2102 return ret;
2103 }
2104
2105 /*
2106 * Needs to be called everytime we run delayed refs, even if there is an error
2107 * in order to cleanup outstanding operations.
2108 */
2109 int btrfs_delayed_qgroup_accounting(struct btrfs_trans_handle *trans,
2110 struct btrfs_fs_info *fs_info)
2111 {
2112 struct btrfs_qgroup_operation *oper;
2113 int ret = 0;
2114
2115 while (!list_empty(&trans->qgroup_ref_list)) {
2116 oper = list_first_entry(&trans->qgroup_ref_list,
2117 struct btrfs_qgroup_operation, list);
2118 list_del_init(&oper->list);
2119 if (!ret || !trans->aborted)
2120 ret = btrfs_qgroup_account(trans, fs_info, oper);
2121 spin_lock(&fs_info->qgroup_op_lock);
2122 rb_erase(&oper->n, &fs_info->qgroup_op_tree);
2123 spin_unlock(&fs_info->qgroup_op_lock);
2124 btrfs_put_tree_mod_seq(fs_info, &oper->elem);
2125 kfree(oper);
2126 }
2127 return ret;
2128 }
2129
2130 /*
2131 * called from commit_transaction. Writes all changed qgroups to disk.
2132 */
2133 int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
2134 struct btrfs_fs_info *fs_info)
2135 {
2136 struct btrfs_root *quota_root = fs_info->quota_root;
2137 int ret = 0;
2138 int start_rescan_worker = 0;
2139
2140 if (!quota_root)
2141 goto out;
2142
2143 if (!fs_info->quota_enabled && fs_info->pending_quota_state)
2144 start_rescan_worker = 1;
2145
2146 fs_info->quota_enabled = fs_info->pending_quota_state;
2147
2148 spin_lock(&fs_info->qgroup_lock);
2149 while (!list_empty(&fs_info->dirty_qgroups)) {
2150 struct btrfs_qgroup *qgroup;
2151 qgroup = list_first_entry(&fs_info->dirty_qgroups,
2152 struct btrfs_qgroup, dirty);
2153 list_del_init(&qgroup->dirty);
2154 spin_unlock(&fs_info->qgroup_lock);
2155 ret = update_qgroup_info_item(trans, quota_root, qgroup);
2156 if (ret)
2157 fs_info->qgroup_flags |=
2158 BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2159 spin_lock(&fs_info->qgroup_lock);
2160 }
2161 if (fs_info->quota_enabled)
2162 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
2163 else
2164 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
2165 spin_unlock(&fs_info->qgroup_lock);
2166
2167 ret = update_qgroup_status_item(trans, fs_info, quota_root);
2168 if (ret)
2169 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2170
2171 if (!ret && start_rescan_worker) {
2172 ret = qgroup_rescan_init(fs_info, 0, 1);
2173 if (!ret) {
2174 qgroup_rescan_zero_tracking(fs_info);
2175 btrfs_queue_work(fs_info->qgroup_rescan_workers,
2176 &fs_info->qgroup_rescan_work);
2177 }
2178 ret = 0;
2179 }
2180
2181 out:
2182
2183 return ret;
2184 }
2185
2186 /*
2187 * copy the acounting information between qgroups. This is necessary when a
2188 * snapshot or a subvolume is created
2189 */
2190 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
2191 struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
2192 struct btrfs_qgroup_inherit *inherit)
2193 {
2194 int ret = 0;
2195 int i;
2196 u64 *i_qgroups;
2197 struct btrfs_root *quota_root = fs_info->quota_root;
2198 struct btrfs_qgroup *srcgroup;
2199 struct btrfs_qgroup *dstgroup;
2200 u32 level_size = 0;
2201 u64 nums;
2202
2203 mutex_lock(&fs_info->qgroup_ioctl_lock);
2204 if (!fs_info->quota_enabled)
2205 goto out;
2206
2207 if (!quota_root) {
2208 ret = -EINVAL;
2209 goto out;
2210 }
2211
2212 if (inherit) {
2213 i_qgroups = (u64 *)(inherit + 1);
2214 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2215 2 * inherit->num_excl_copies;
2216 for (i = 0; i < nums; ++i) {
2217 srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
2218 if (!srcgroup) {
2219 ret = -EINVAL;
2220 goto out;
2221 }
2222 ++i_qgroups;
2223 }
2224 }
2225
2226 /*
2227 * create a tracking group for the subvol itself
2228 */
2229 ret = add_qgroup_item(trans, quota_root, objectid);
2230 if (ret)
2231 goto out;
2232
2233 if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
2234 ret = update_qgroup_limit_item(trans, quota_root, objectid,
2235 inherit->lim.flags,
2236 inherit->lim.max_rfer,
2237 inherit->lim.max_excl,
2238 inherit->lim.rsv_rfer,
2239 inherit->lim.rsv_excl);
2240 if (ret)
2241 goto out;
2242 }
2243
2244 if (srcid) {
2245 struct btrfs_root *srcroot;
2246 struct btrfs_key srckey;
2247
2248 srckey.objectid = srcid;
2249 srckey.type = BTRFS_ROOT_ITEM_KEY;
2250 srckey.offset = (u64)-1;
2251 srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
2252 if (IS_ERR(srcroot)) {
2253 ret = PTR_ERR(srcroot);
2254 goto out;
2255 }
2256
2257 rcu_read_lock();
2258 level_size = srcroot->nodesize;
2259 rcu_read_unlock();
2260 }
2261
2262 /*
2263 * add qgroup to all inherited groups
2264 */
2265 if (inherit) {
2266 i_qgroups = (u64 *)(inherit + 1);
2267 for (i = 0; i < inherit->num_qgroups; ++i) {
2268 ret = add_qgroup_relation_item(trans, quota_root,
2269 objectid, *i_qgroups);
2270 if (ret)
2271 goto out;
2272 ret = add_qgroup_relation_item(trans, quota_root,
2273 *i_qgroups, objectid);
2274 if (ret)
2275 goto out;
2276 ++i_qgroups;
2277 }
2278 }
2279
2280
2281 spin_lock(&fs_info->qgroup_lock);
2282
2283 dstgroup = add_qgroup_rb(fs_info, objectid);
2284 if (IS_ERR(dstgroup)) {
2285 ret = PTR_ERR(dstgroup);
2286 goto unlock;
2287 }
2288
2289 if (srcid) {
2290 srcgroup = find_qgroup_rb(fs_info, srcid);
2291 if (!srcgroup)
2292 goto unlock;
2293
2294 /*
2295 * We call inherit after we clone the root in order to make sure
2296 * our counts don't go crazy, so at this point the only
2297 * difference between the two roots should be the root node.
2298 */
2299 dstgroup->rfer = srcgroup->rfer;
2300 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
2301 dstgroup->excl = level_size;
2302 dstgroup->excl_cmpr = level_size;
2303 srcgroup->excl = level_size;
2304 srcgroup->excl_cmpr = level_size;
2305
2306 /* inherit the limit info */
2307 dstgroup->lim_flags = srcgroup->lim_flags;
2308 dstgroup->max_rfer = srcgroup->max_rfer;
2309 dstgroup->max_excl = srcgroup->max_excl;
2310 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
2311 dstgroup->rsv_excl = srcgroup->rsv_excl;
2312
2313 qgroup_dirty(fs_info, dstgroup);
2314 qgroup_dirty(fs_info, srcgroup);
2315 }
2316
2317 if (!inherit)
2318 goto unlock;
2319
2320 i_qgroups = (u64 *)(inherit + 1);
2321 for (i = 0; i < inherit->num_qgroups; ++i) {
2322 ret = add_relation_rb(quota_root->fs_info, objectid,
2323 *i_qgroups);
2324 if (ret)
2325 goto unlock;
2326 ++i_qgroups;
2327 }
2328
2329 for (i = 0; i < inherit->num_ref_copies; ++i) {
2330 struct btrfs_qgroup *src;
2331 struct btrfs_qgroup *dst;
2332
2333 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2334 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2335
2336 if (!src || !dst) {
2337 ret = -EINVAL;
2338 goto unlock;
2339 }
2340
2341 dst->rfer = src->rfer - level_size;
2342 dst->rfer_cmpr = src->rfer_cmpr - level_size;
2343 i_qgroups += 2;
2344 }
2345 for (i = 0; i < inherit->num_excl_copies; ++i) {
2346 struct btrfs_qgroup *src;
2347 struct btrfs_qgroup *dst;
2348
2349 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2350 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2351
2352 if (!src || !dst) {
2353 ret = -EINVAL;
2354 goto unlock;
2355 }
2356
2357 dst->excl = src->excl + level_size;
2358 dst->excl_cmpr = src->excl_cmpr + level_size;
2359 i_qgroups += 2;
2360 }
2361
2362 unlock:
2363 spin_unlock(&fs_info->qgroup_lock);
2364 out:
2365 mutex_unlock(&fs_info->qgroup_ioctl_lock);
2366 return ret;
2367 }
2368
2369 /*
2370 * reserve some space for a qgroup and all its parents. The reservation takes
2371 * place with start_transaction or dealloc_reserve, similar to ENOSPC
2372 * accounting. If not enough space is available, EDQUOT is returned.
2373 * We assume that the requested space is new for all qgroups.
2374 */
2375 int btrfs_qgroup_reserve(struct btrfs_root *root, u64 num_bytes)
2376 {
2377 struct btrfs_root *quota_root;
2378 struct btrfs_qgroup *qgroup;
2379 struct btrfs_fs_info *fs_info = root->fs_info;
2380 u64 ref_root = root->root_key.objectid;
2381 int ret = 0;
2382 struct ulist_node *unode;
2383 struct ulist_iterator uiter;
2384
2385 if (!is_fstree(ref_root))
2386 return 0;
2387
2388 if (num_bytes == 0)
2389 return 0;
2390
2391 spin_lock(&fs_info->qgroup_lock);
2392 quota_root = fs_info->quota_root;
2393 if (!quota_root)
2394 goto out;
2395
2396 qgroup = find_qgroup_rb(fs_info, ref_root);
2397 if (!qgroup)
2398 goto out;
2399
2400 /*
2401 * in a first step, we check all affected qgroups if any limits would
2402 * be exceeded
2403 */
2404 ulist_reinit(fs_info->qgroup_ulist);
2405 ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2406 (uintptr_t)qgroup, GFP_ATOMIC);
2407 if (ret < 0)
2408 goto out;
2409 ULIST_ITER_INIT(&uiter);
2410 while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2411 struct btrfs_qgroup *qg;
2412 struct btrfs_qgroup_list *glist;
2413
2414 qg = u64_to_ptr(unode->aux);
2415
2416 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2417 qg->reserved + (s64)qg->rfer + num_bytes >
2418 qg->max_rfer) {
2419 ret = -EDQUOT;
2420 goto out;
2421 }
2422
2423 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2424 qg->reserved + (s64)qg->excl + num_bytes >
2425 qg->max_excl) {
2426 ret = -EDQUOT;
2427 goto out;
2428 }
2429
2430 list_for_each_entry(glist, &qg->groups, next_group) {
2431 ret = ulist_add(fs_info->qgroup_ulist,
2432 glist->group->qgroupid,
2433 (uintptr_t)glist->group, GFP_ATOMIC);
2434 if (ret < 0)
2435 goto out;
2436 }
2437 }
2438 ret = 0;
2439 /*
2440 * no limits exceeded, now record the reservation into all qgroups
2441 */
2442 ULIST_ITER_INIT(&uiter);
2443 while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2444 struct btrfs_qgroup *qg;
2445
2446 qg = u64_to_ptr(unode->aux);
2447
2448 qg->reserved += num_bytes;
2449 }
2450
2451 out:
2452 spin_unlock(&fs_info->qgroup_lock);
2453 return ret;
2454 }
2455
2456 void btrfs_qgroup_free(struct btrfs_root *root, u64 num_bytes)
2457 {
2458 struct btrfs_root *quota_root;
2459 struct btrfs_qgroup *qgroup;
2460 struct btrfs_fs_info *fs_info = root->fs_info;
2461 struct ulist_node *unode;
2462 struct ulist_iterator uiter;
2463 u64 ref_root = root->root_key.objectid;
2464 int ret = 0;
2465
2466 if (!is_fstree(ref_root))
2467 return;
2468
2469 if (num_bytes == 0)
2470 return;
2471
2472 spin_lock(&fs_info->qgroup_lock);
2473
2474 quota_root = fs_info->quota_root;
2475 if (!quota_root)
2476 goto out;
2477
2478 qgroup = find_qgroup_rb(fs_info, ref_root);
2479 if (!qgroup)
2480 goto out;
2481
2482 ulist_reinit(fs_info->qgroup_ulist);
2483 ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2484 (uintptr_t)qgroup, GFP_ATOMIC);
2485 if (ret < 0)
2486 goto out;
2487 ULIST_ITER_INIT(&uiter);
2488 while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2489 struct btrfs_qgroup *qg;
2490 struct btrfs_qgroup_list *glist;
2491
2492 qg = u64_to_ptr(unode->aux);
2493
2494 qg->reserved -= num_bytes;
2495
2496 list_for_each_entry(glist, &qg->groups, next_group) {
2497 ret = ulist_add(fs_info->qgroup_ulist,
2498 glist->group->qgroupid,
2499 (uintptr_t)glist->group, GFP_ATOMIC);
2500 if (ret < 0)
2501 goto out;
2502 }
2503 }
2504
2505 out:
2506 spin_unlock(&fs_info->qgroup_lock);
2507 }
2508
2509 void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
2510 {
2511 if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
2512 return;
2513 btrfs_err(trans->root->fs_info,
2514 "qgroups not uptodate in trans handle %p: list is%s empty, "
2515 "seq is %#x.%x",
2516 trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
2517 (u32)(trans->delayed_ref_elem.seq >> 32),
2518 (u32)trans->delayed_ref_elem.seq);
2519 BUG();
2520 }
2521
2522 /*
2523 * returns < 0 on error, 0 when more leafs are to be scanned.
2524 * returns 1 when done, 2 when done and FLAG_INCONSISTENT was cleared.
2525 */
2526 static int
2527 qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
2528 struct btrfs_trans_handle *trans, struct ulist *qgroups,
2529 struct ulist *tmp, struct extent_buffer *scratch_leaf)
2530 {
2531 struct btrfs_key found;
2532 struct ulist *roots = NULL;
2533 struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
2534 u64 num_bytes;
2535 u64 seq;
2536 int new_roots;
2537 int slot;
2538 int ret;
2539
2540 path->leave_spinning = 1;
2541 mutex_lock(&fs_info->qgroup_rescan_lock);
2542 ret = btrfs_search_slot_for_read(fs_info->extent_root,
2543 &fs_info->qgroup_rescan_progress,
2544 path, 1, 0);
2545
2546 pr_debug("current progress key (%llu %u %llu), search_slot ret %d\n",
2547 fs_info->qgroup_rescan_progress.objectid,
2548 fs_info->qgroup_rescan_progress.type,
2549 fs_info->qgroup_rescan_progress.offset, ret);
2550
2551 if (ret) {
2552 /*
2553 * The rescan is about to end, we will not be scanning any
2554 * further blocks. We cannot unset the RESCAN flag here, because
2555 * we want to commit the transaction if everything went well.
2556 * To make the live accounting work in this phase, we set our
2557 * scan progress pointer such that every real extent objectid
2558 * will be smaller.
2559 */
2560 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
2561 btrfs_release_path(path);
2562 mutex_unlock(&fs_info->qgroup_rescan_lock);
2563 return ret;
2564 }
2565
2566 btrfs_item_key_to_cpu(path->nodes[0], &found,
2567 btrfs_header_nritems(path->nodes[0]) - 1);
2568 fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
2569
2570 btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2571 memcpy(scratch_leaf, path->nodes[0], sizeof(*scratch_leaf));
2572 slot = path->slots[0];
2573 btrfs_release_path(path);
2574 mutex_unlock(&fs_info->qgroup_rescan_lock);
2575
2576 for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
2577 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
2578 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
2579 found.type != BTRFS_METADATA_ITEM_KEY)
2580 continue;
2581 if (found.type == BTRFS_METADATA_ITEM_KEY)
2582 num_bytes = fs_info->extent_root->nodesize;
2583 else
2584 num_bytes = found.offset;
2585
2586 ulist_reinit(qgroups);
2587 ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
2588 &roots);
2589 if (ret < 0)
2590 goto out;
2591 spin_lock(&fs_info->qgroup_lock);
2592 seq = fs_info->qgroup_seq;
2593 fs_info->qgroup_seq += roots->nnodes + 1; /* max refcnt */
2594
2595 new_roots = 0;
2596 ret = qgroup_calc_old_refcnt(fs_info, 0, tmp, roots, qgroups,
2597 seq, &new_roots, 1);
2598 if (ret < 0) {
2599 spin_unlock(&fs_info->qgroup_lock);
2600 ulist_free(roots);
2601 goto out;
2602 }
2603
2604 ret = qgroup_adjust_counters(fs_info, 0, num_bytes, qgroups,
2605 seq, 0, new_roots, 1);
2606 if (ret < 0) {
2607 spin_unlock(&fs_info->qgroup_lock);
2608 ulist_free(roots);
2609 goto out;
2610 }
2611 spin_unlock(&fs_info->qgroup_lock);
2612 ulist_free(roots);
2613 }
2614 out:
2615 btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2616
2617 return ret;
2618 }
2619
2620 static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
2621 {
2622 struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
2623 qgroup_rescan_work);
2624 struct btrfs_path *path;
2625 struct btrfs_trans_handle *trans = NULL;
2626 struct ulist *tmp = NULL, *qgroups = NULL;
2627 struct extent_buffer *scratch_leaf = NULL;
2628 int err = -ENOMEM;
2629
2630 path = btrfs_alloc_path();
2631 if (!path)
2632 goto out;
2633 qgroups = ulist_alloc(GFP_NOFS);
2634 if (!qgroups)
2635 goto out;
2636 tmp = ulist_alloc(GFP_NOFS);
2637 if (!tmp)
2638 goto out;
2639 scratch_leaf = kmalloc(sizeof(*scratch_leaf), GFP_NOFS);
2640 if (!scratch_leaf)
2641 goto out;
2642
2643 err = 0;
2644 while (!err) {
2645 trans = btrfs_start_transaction(fs_info->fs_root, 0);
2646 if (IS_ERR(trans)) {
2647 err = PTR_ERR(trans);
2648 break;
2649 }
2650 if (!fs_info->quota_enabled) {
2651 err = -EINTR;
2652 } else {
2653 err = qgroup_rescan_leaf(fs_info, path, trans,
2654 qgroups, tmp, scratch_leaf);
2655 }
2656 if (err > 0)
2657 btrfs_commit_transaction(trans, fs_info->fs_root);
2658 else
2659 btrfs_end_transaction(trans, fs_info->fs_root);
2660 }
2661
2662 out:
2663 kfree(scratch_leaf);
2664 ulist_free(qgroups);
2665 ulist_free(tmp);
2666 btrfs_free_path(path);
2667
2668 mutex_lock(&fs_info->qgroup_rescan_lock);
2669 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2670
2671 if (err == 2 &&
2672 fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
2673 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2674 } else if (err < 0) {
2675 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2676 }
2677 mutex_unlock(&fs_info->qgroup_rescan_lock);
2678
2679 if (err >= 0) {
2680 btrfs_info(fs_info, "qgroup scan completed%s",
2681 err == 2 ? " (inconsistency flag cleared)" : "");
2682 } else {
2683 btrfs_err(fs_info, "qgroup scan failed with %d", err);
2684 }
2685
2686 complete_all(&fs_info->qgroup_rescan_completion);
2687 }
2688
2689 /*
2690 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
2691 * memory required for the rescan context.
2692 */
2693 static int
2694 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
2695 int init_flags)
2696 {
2697 int ret = 0;
2698
2699 if (!init_flags &&
2700 (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
2701 !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
2702 ret = -EINVAL;
2703 goto err;
2704 }
2705
2706 mutex_lock(&fs_info->qgroup_rescan_lock);
2707 spin_lock(&fs_info->qgroup_lock);
2708
2709 if (init_flags) {
2710 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2711 ret = -EINPROGRESS;
2712 else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
2713 ret = -EINVAL;
2714
2715 if (ret) {
2716 spin_unlock(&fs_info->qgroup_lock);
2717 mutex_unlock(&fs_info->qgroup_rescan_lock);
2718 goto err;
2719 }
2720
2721 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2722 }
2723
2724 memset(&fs_info->qgroup_rescan_progress, 0,
2725 sizeof(fs_info->qgroup_rescan_progress));
2726 fs_info->qgroup_rescan_progress.objectid = progress_objectid;
2727
2728 spin_unlock(&fs_info->qgroup_lock);
2729 mutex_unlock(&fs_info->qgroup_rescan_lock);
2730
2731 init_completion(&fs_info->qgroup_rescan_completion);
2732
2733 memset(&fs_info->qgroup_rescan_work, 0,
2734 sizeof(fs_info->qgroup_rescan_work));
2735 btrfs_init_work(&fs_info->qgroup_rescan_work,
2736 btrfs_qgroup_rescan_helper,
2737 btrfs_qgroup_rescan_worker, NULL, NULL);
2738
2739 if (ret) {
2740 err:
2741 btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
2742 return ret;
2743 }
2744
2745 return 0;
2746 }
2747
2748 static void
2749 qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
2750 {
2751 struct rb_node *n;
2752 struct btrfs_qgroup *qgroup;
2753
2754 spin_lock(&fs_info->qgroup_lock);
2755 /* clear all current qgroup tracking information */
2756 for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
2757 qgroup = rb_entry(n, struct btrfs_qgroup, node);
2758 qgroup->rfer = 0;
2759 qgroup->rfer_cmpr = 0;
2760 qgroup->excl = 0;
2761 qgroup->excl_cmpr = 0;
2762 }
2763 spin_unlock(&fs_info->qgroup_lock);
2764 }
2765
2766 int
2767 btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
2768 {
2769 int ret = 0;
2770 struct btrfs_trans_handle *trans;
2771
2772 ret = qgroup_rescan_init(fs_info, 0, 1);
2773 if (ret)
2774 return ret;
2775
2776 /*
2777 * We have set the rescan_progress to 0, which means no more
2778 * delayed refs will be accounted by btrfs_qgroup_account_ref.
2779 * However, btrfs_qgroup_account_ref may be right after its call
2780 * to btrfs_find_all_roots, in which case it would still do the
2781 * accounting.
2782 * To solve this, we're committing the transaction, which will
2783 * ensure we run all delayed refs and only after that, we are
2784 * going to clear all tracking information for a clean start.
2785 */
2786
2787 trans = btrfs_join_transaction(fs_info->fs_root);
2788 if (IS_ERR(trans)) {
2789 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2790 return PTR_ERR(trans);
2791 }
2792 ret = btrfs_commit_transaction(trans, fs_info->fs_root);
2793 if (ret) {
2794 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2795 return ret;
2796 }
2797
2798 qgroup_rescan_zero_tracking(fs_info);
2799
2800 btrfs_queue_work(fs_info->qgroup_rescan_workers,
2801 &fs_info->qgroup_rescan_work);
2802
2803 return 0;
2804 }
2805
2806 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
2807 {
2808 int running;
2809 int ret = 0;
2810
2811 mutex_lock(&fs_info->qgroup_rescan_lock);
2812 spin_lock(&fs_info->qgroup_lock);
2813 running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2814 spin_unlock(&fs_info->qgroup_lock);
2815 mutex_unlock(&fs_info->qgroup_rescan_lock);
2816
2817 if (running)
2818 ret = wait_for_completion_interruptible(
2819 &fs_info->qgroup_rescan_completion);
2820
2821 return ret;
2822 }
2823
2824 /*
2825 * this is only called from open_ctree where we're still single threaded, thus
2826 * locking is omitted here.
2827 */
2828 void
2829 btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
2830 {
2831 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2832 btrfs_queue_work(fs_info->qgroup_rescan_workers,
2833 &fs_info->qgroup_rescan_work);
2834 }
(deprecated) Btrfs devel tree