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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2011 STRATO. All rights reserved.
4 */
5
6#include <linux/sched.h>
7#include <linux/pagemap.h>
8#include <linux/writeback.h>
9#include <linux/blkdev.h>
10#include <linux/rbtree.h>
11#include <linux/slab.h>
12#include <linux/workqueue.h>
13#include <linux/btrfs.h>
14#include <linux/sched/mm.h>
15
16#include "ctree.h"
17#include "transaction.h"
18#include "disk-io.h"
19#include "locking.h"
20#include "ulist.h"
21#include "backref.h"
22#include "extent_io.h"
23#include "qgroup.h"
24#include "block-group.h"
25#include "sysfs.h"
26#include "tree-mod-log.h"
27#include "fs.h"
28#include "accessors.h"
29#include "extent-tree.h"
30#include "root-tree.h"
31#include "tree-checker.h"
32
33enum btrfs_qgroup_mode btrfs_qgroup_mode(struct btrfs_fs_info *fs_info)
34{
35 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
36 return BTRFS_QGROUP_MODE_DISABLED;
37 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE)
38 return BTRFS_QGROUP_MODE_SIMPLE;
39 return BTRFS_QGROUP_MODE_FULL;
40}
41
42bool btrfs_qgroup_enabled(struct btrfs_fs_info *fs_info)
43{
44 return btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_DISABLED;
45}
46
47bool btrfs_qgroup_full_accounting(struct btrfs_fs_info *fs_info)
48{
49 return btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL;
50}
51
52/*
53 * Helpers to access qgroup reservation
54 *
55 * Callers should ensure the lock context and type are valid
56 */
57
58static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
59{
60 u64 ret = 0;
61 int i;
62
63 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
64 ret += qgroup->rsv.values[i];
65
66 return ret;
67}
68
69#ifdef CONFIG_BTRFS_DEBUG
70static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
71{
72 if (type == BTRFS_QGROUP_RSV_DATA)
73 return "data";
74 if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
75 return "meta_pertrans";
76 if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
77 return "meta_prealloc";
78 return NULL;
79}
80#endif
81
82static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
83 struct btrfs_qgroup *qgroup, u64 num_bytes,
84 enum btrfs_qgroup_rsv_type type)
85{
86 trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
87 qgroup->rsv.values[type] += num_bytes;
88}
89
90static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
91 struct btrfs_qgroup *qgroup, u64 num_bytes,
92 enum btrfs_qgroup_rsv_type type)
93{
94 trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
95 if (qgroup->rsv.values[type] >= num_bytes) {
96 qgroup->rsv.values[type] -= num_bytes;
97 return;
98 }
99#ifdef CONFIG_BTRFS_DEBUG
100 WARN_RATELIMIT(1,
101 "qgroup %llu %s reserved space underflow, have %llu to free %llu",
102 qgroup->qgroupid, qgroup_rsv_type_str(type),
103 qgroup->rsv.values[type], num_bytes);
104#endif
105 qgroup->rsv.values[type] = 0;
106}
107
108static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
109 struct btrfs_qgroup *dest,
110 struct btrfs_qgroup *src)
111{
112 int i;
113
114 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
115 qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
116}
117
118static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
119 struct btrfs_qgroup *dest,
120 struct btrfs_qgroup *src)
121{
122 int i;
123
124 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
125 qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
126}
127
128static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
129 int mod)
130{
131 if (qg->old_refcnt < seq)
132 qg->old_refcnt = seq;
133 qg->old_refcnt += mod;
134}
135
136static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
137 int mod)
138{
139 if (qg->new_refcnt < seq)
140 qg->new_refcnt = seq;
141 qg->new_refcnt += mod;
142}
143
144static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
145{
146 if (qg->old_refcnt < seq)
147 return 0;
148 return qg->old_refcnt - seq;
149}
150
151static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
152{
153 if (qg->new_refcnt < seq)
154 return 0;
155 return qg->new_refcnt - seq;
156}
157
158/*
159 * glue structure to represent the relations between qgroups.
160 */
161struct btrfs_qgroup_list {
162 struct list_head next_group;
163 struct list_head next_member;
164 struct btrfs_qgroup *group;
165 struct btrfs_qgroup *member;
166};
167
168static int
169qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
170 int init_flags);
171static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
172
173/* must be called with qgroup_ioctl_lock held */
174static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
175 u64 qgroupid)
176{
177 struct rb_node *n = fs_info->qgroup_tree.rb_node;
178 struct btrfs_qgroup *qgroup;
179
180 while (n) {
181 qgroup = rb_entry(n, struct btrfs_qgroup, node);
182 if (qgroup->qgroupid < qgroupid)
183 n = n->rb_left;
184 else if (qgroup->qgroupid > qgroupid)
185 n = n->rb_right;
186 else
187 return qgroup;
188 }
189 return NULL;
190}
191
192/*
193 * Add qgroup to the filesystem's qgroup tree.
194 *
195 * Must be called with qgroup_lock held and @prealloc preallocated.
196 *
197 * The control on the lifespan of @prealloc would be transferred to this
198 * function, thus caller should no longer touch @prealloc.
199 */
200static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
201 struct btrfs_qgroup *prealloc,
202 u64 qgroupid)
203{
204 struct rb_node **p = &fs_info->qgroup_tree.rb_node;
205 struct rb_node *parent = NULL;
206 struct btrfs_qgroup *qgroup;
207
208 /* Caller must have pre-allocated @prealloc. */
209 ASSERT(prealloc);
210
211 while (*p) {
212 parent = *p;
213 qgroup = rb_entry(parent, struct btrfs_qgroup, node);
214
215 if (qgroup->qgroupid < qgroupid) {
216 p = &(*p)->rb_left;
217 } else if (qgroup->qgroupid > qgroupid) {
218 p = &(*p)->rb_right;
219 } else {
220 kfree(prealloc);
221 return qgroup;
222 }
223 }
224
225 qgroup = prealloc;
226 qgroup->qgroupid = qgroupid;
227 INIT_LIST_HEAD(&qgroup->groups);
228 INIT_LIST_HEAD(&qgroup->members);
229 INIT_LIST_HEAD(&qgroup->dirty);
230 INIT_LIST_HEAD(&qgroup->iterator);
231 INIT_LIST_HEAD(&qgroup->nested_iterator);
232
233 rb_link_node(&qgroup->node, parent, p);
234 rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
235
236 return qgroup;
237}
238
239static void __del_qgroup_rb(struct btrfs_fs_info *fs_info,
240 struct btrfs_qgroup *qgroup)
241{
242 struct btrfs_qgroup_list *list;
243
244 list_del(&qgroup->dirty);
245 while (!list_empty(&qgroup->groups)) {
246 list = list_first_entry(&qgroup->groups,
247 struct btrfs_qgroup_list, next_group);
248 list_del(&list->next_group);
249 list_del(&list->next_member);
250 kfree(list);
251 }
252
253 while (!list_empty(&qgroup->members)) {
254 list = list_first_entry(&qgroup->members,
255 struct btrfs_qgroup_list, next_member);
256 list_del(&list->next_group);
257 list_del(&list->next_member);
258 kfree(list);
259 }
260}
261
262/* must be called with qgroup_lock held */
263static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
264{
265 struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
266
267 if (!qgroup)
268 return -ENOENT;
269
270 rb_erase(&qgroup->node, &fs_info->qgroup_tree);
271 __del_qgroup_rb(fs_info, qgroup);
272 return 0;
273}
274
275/*
276 * Add relation specified by two qgroups.
277 *
278 * Must be called with qgroup_lock held, the ownership of @prealloc is
279 * transferred to this function and caller should not touch it anymore.
280 *
281 * Return: 0 on success
282 * -ENOENT if one of the qgroups is NULL
283 * <0 other errors
284 */
285static int __add_relation_rb(struct btrfs_qgroup_list *prealloc,
286 struct btrfs_qgroup *member,
287 struct btrfs_qgroup *parent)
288{
289 if (!member || !parent) {
290 kfree(prealloc);
291 return -ENOENT;
292 }
293
294 prealloc->group = parent;
295 prealloc->member = member;
296 list_add_tail(&prealloc->next_group, &member->groups);
297 list_add_tail(&prealloc->next_member, &parent->members);
298
299 return 0;
300}
301
302/*
303 * Add relation specified by two qgroup ids.
304 *
305 * Must be called with qgroup_lock held.
306 *
307 * Return: 0 on success
308 * -ENOENT if one of the ids does not exist
309 * <0 other errors
310 */
311static int add_relation_rb(struct btrfs_fs_info *fs_info,
312 struct btrfs_qgroup_list *prealloc,
313 u64 memberid, u64 parentid)
314{
315 struct btrfs_qgroup *member;
316 struct btrfs_qgroup *parent;
317
318 member = find_qgroup_rb(fs_info, memberid);
319 parent = find_qgroup_rb(fs_info, parentid);
320
321 return __add_relation_rb(prealloc, member, parent);
322}
323
324/* Must be called with qgroup_lock held */
325static int del_relation_rb(struct btrfs_fs_info *fs_info,
326 u64 memberid, u64 parentid)
327{
328 struct btrfs_qgroup *member;
329 struct btrfs_qgroup *parent;
330 struct btrfs_qgroup_list *list;
331
332 member = find_qgroup_rb(fs_info, memberid);
333 parent = find_qgroup_rb(fs_info, parentid);
334 if (!member || !parent)
335 return -ENOENT;
336
337 list_for_each_entry(list, &member->groups, next_group) {
338 if (list->group == parent) {
339 list_del(&list->next_group);
340 list_del(&list->next_member);
341 kfree(list);
342 return 0;
343 }
344 }
345 return -ENOENT;
346}
347
348#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
349int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
350 u64 rfer, u64 excl)
351{
352 struct btrfs_qgroup *qgroup;
353
354 qgroup = find_qgroup_rb(fs_info, qgroupid);
355 if (!qgroup)
356 return -EINVAL;
357 if (qgroup->rfer != rfer || qgroup->excl != excl)
358 return -EINVAL;
359 return 0;
360}
361#endif
362
363static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info)
364{
365 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
366 return;
367 fs_info->qgroup_flags |= (BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT |
368 BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
369 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
370}
371
372static void qgroup_read_enable_gen(struct btrfs_fs_info *fs_info,
373 struct extent_buffer *leaf, int slot,
374 struct btrfs_qgroup_status_item *ptr)
375{
376 ASSERT(btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
377 ASSERT(btrfs_item_size(leaf, slot) >= sizeof(*ptr));
378 fs_info->qgroup_enable_gen = btrfs_qgroup_status_enable_gen(leaf, ptr);
379}
380
381/*
382 * The full config is read in one go, only called from open_ctree()
383 * It doesn't use any locking, as at this point we're still single-threaded
384 */
385int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
386{
387 struct btrfs_key key;
388 struct btrfs_key found_key;
389 struct btrfs_root *quota_root = fs_info->quota_root;
390 struct btrfs_path *path = NULL;
391 struct extent_buffer *l;
392 int slot;
393 int ret = 0;
394 u64 flags = 0;
395 u64 rescan_progress = 0;
396
397 if (!fs_info->quota_root)
398 return 0;
399
400 fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
401 if (!fs_info->qgroup_ulist) {
402 ret = -ENOMEM;
403 goto out;
404 }
405
406 path = btrfs_alloc_path();
407 if (!path) {
408 ret = -ENOMEM;
409 goto out;
410 }
411
412 ret = btrfs_sysfs_add_qgroups(fs_info);
413 if (ret < 0)
414 goto out;
415 /* default this to quota off, in case no status key is found */
416 fs_info->qgroup_flags = 0;
417
418 /*
419 * pass 1: read status, all qgroup infos and limits
420 */
421 key.objectid = 0;
422 key.type = 0;
423 key.offset = 0;
424 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
425 if (ret)
426 goto out;
427
428 while (1) {
429 struct btrfs_qgroup *qgroup;
430
431 slot = path->slots[0];
432 l = path->nodes[0];
433 btrfs_item_key_to_cpu(l, &found_key, slot);
434
435 if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
436 struct btrfs_qgroup_status_item *ptr;
437
438 ptr = btrfs_item_ptr(l, slot,
439 struct btrfs_qgroup_status_item);
440
441 if (btrfs_qgroup_status_version(l, ptr) !=
442 BTRFS_QGROUP_STATUS_VERSION) {
443 btrfs_err(fs_info,
444 "old qgroup version, quota disabled");
445 goto out;
446 }
447 fs_info->qgroup_flags = btrfs_qgroup_status_flags(l, ptr);
448 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE) {
449 qgroup_read_enable_gen(fs_info, l, slot, ptr);
450 } else if (btrfs_qgroup_status_generation(l, ptr) != fs_info->generation) {
451 qgroup_mark_inconsistent(fs_info);
452 btrfs_err(fs_info,
453 "qgroup generation mismatch, marked as inconsistent");
454 }
455 rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
456 goto next1;
457 }
458
459 if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
460 found_key.type != BTRFS_QGROUP_LIMIT_KEY)
461 goto next1;
462
463 qgroup = find_qgroup_rb(fs_info, found_key.offset);
464 if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
465 (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
466 btrfs_err(fs_info, "inconsistent qgroup config");
467 qgroup_mark_inconsistent(fs_info);
468 }
469 if (!qgroup) {
470 struct btrfs_qgroup *prealloc;
471
472 prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);
473 if (!prealloc) {
474 ret = -ENOMEM;
475 goto out;
476 }
477 qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
478 }
479 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
480 if (ret < 0)
481 goto out;
482
483 switch (found_key.type) {
484 case BTRFS_QGROUP_INFO_KEY: {
485 struct btrfs_qgroup_info_item *ptr;
486
487 ptr = btrfs_item_ptr(l, slot,
488 struct btrfs_qgroup_info_item);
489 qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
490 qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
491 qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
492 qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
493 /* generation currently unused */
494 break;
495 }
496 case BTRFS_QGROUP_LIMIT_KEY: {
497 struct btrfs_qgroup_limit_item *ptr;
498
499 ptr = btrfs_item_ptr(l, slot,
500 struct btrfs_qgroup_limit_item);
501 qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
502 qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
503 qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
504 qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
505 qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
506 break;
507 }
508 }
509next1:
510 ret = btrfs_next_item(quota_root, path);
511 if (ret < 0)
512 goto out;
513 if (ret)
514 break;
515 }
516 btrfs_release_path(path);
517
518 /*
519 * pass 2: read all qgroup relations
520 */
521 key.objectid = 0;
522 key.type = BTRFS_QGROUP_RELATION_KEY;
523 key.offset = 0;
524 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
525 if (ret)
526 goto out;
527 while (1) {
528 struct btrfs_qgroup_list *list = NULL;
529
530 slot = path->slots[0];
531 l = path->nodes[0];
532 btrfs_item_key_to_cpu(l, &found_key, slot);
533
534 if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
535 goto next2;
536
537 if (found_key.objectid > found_key.offset) {
538 /* parent <- member, not needed to build config */
539 /* FIXME should we omit the key completely? */
540 goto next2;
541 }
542
543 list = kzalloc(sizeof(*list), GFP_KERNEL);
544 if (!list) {
545 ret = -ENOMEM;
546 goto out;
547 }
548 ret = add_relation_rb(fs_info, list, found_key.objectid,
549 found_key.offset);
550 list = NULL;
551 if (ret == -ENOENT) {
552 btrfs_warn(fs_info,
553 "orphan qgroup relation 0x%llx->0x%llx",
554 found_key.objectid, found_key.offset);
555 ret = 0; /* ignore the error */
556 }
557 if (ret)
558 goto out;
559next2:
560 ret = btrfs_next_item(quota_root, path);
561 if (ret < 0)
562 goto out;
563 if (ret)
564 break;
565 }
566out:
567 btrfs_free_path(path);
568 fs_info->qgroup_flags |= flags;
569 if (ret >= 0) {
570 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)
571 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
572 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
573 ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
574 } else {
575 ulist_free(fs_info->qgroup_ulist);
576 fs_info->qgroup_ulist = NULL;
577 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
578 btrfs_sysfs_del_qgroups(fs_info);
579 }
580
581 return ret < 0 ? ret : 0;
582}
583
584/*
585 * Called in close_ctree() when quota is still enabled. This verifies we don't
586 * leak some reserved space.
587 *
588 * Return false if no reserved space is left.
589 * Return true if some reserved space is leaked.
590 */
591bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info)
592{
593 struct rb_node *node;
594 bool ret = false;
595
596 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
597 return ret;
598 /*
599 * Since we're unmounting, there is no race and no need to grab qgroup
600 * lock. And here we don't go post-order to provide a more user
601 * friendly sorted result.
602 */
603 for (node = rb_first(&fs_info->qgroup_tree); node; node = rb_next(node)) {
604 struct btrfs_qgroup *qgroup;
605 int i;
606
607 qgroup = rb_entry(node, struct btrfs_qgroup, node);
608 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) {
609 if (qgroup->rsv.values[i]) {
610 ret = true;
611 btrfs_warn(fs_info,
612 "qgroup %hu/%llu has unreleased space, type %d rsv %llu",
613 btrfs_qgroup_level(qgroup->qgroupid),
614 btrfs_qgroup_subvolid(qgroup->qgroupid),
615 i, qgroup->rsv.values[i]);
616 }
617 }
618 }
619 return ret;
620}
621
622/*
623 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
624 * first two are in single-threaded paths.And for the third one, we have set
625 * quota_root to be null with qgroup_lock held before, so it is safe to clean
626 * up the in-memory structures without qgroup_lock held.
627 */
628void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
629{
630 struct rb_node *n;
631 struct btrfs_qgroup *qgroup;
632
633 while ((n = rb_first(&fs_info->qgroup_tree))) {
634 qgroup = rb_entry(n, struct btrfs_qgroup, node);
635 rb_erase(n, &fs_info->qgroup_tree);
636 __del_qgroup_rb(fs_info, qgroup);
637 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
638 kfree(qgroup);
639 }
640 /*
641 * We call btrfs_free_qgroup_config() when unmounting
642 * filesystem and disabling quota, so we set qgroup_ulist
643 * to be null here to avoid double free.
644 */
645 ulist_free(fs_info->qgroup_ulist);
646 fs_info->qgroup_ulist = NULL;
647 btrfs_sysfs_del_qgroups(fs_info);
648}
649
650static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
651 u64 dst)
652{
653 int ret;
654 struct btrfs_root *quota_root = trans->fs_info->quota_root;
655 struct btrfs_path *path;
656 struct btrfs_key key;
657
658 path = btrfs_alloc_path();
659 if (!path)
660 return -ENOMEM;
661
662 key.objectid = src;
663 key.type = BTRFS_QGROUP_RELATION_KEY;
664 key.offset = dst;
665
666 ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
667
668 btrfs_mark_buffer_dirty(trans, path->nodes[0]);
669
670 btrfs_free_path(path);
671 return ret;
672}
673
674static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
675 u64 dst)
676{
677 int ret;
678 struct btrfs_root *quota_root = trans->fs_info->quota_root;
679 struct btrfs_path *path;
680 struct btrfs_key key;
681
682 path = btrfs_alloc_path();
683 if (!path)
684 return -ENOMEM;
685
686 key.objectid = src;
687 key.type = BTRFS_QGROUP_RELATION_KEY;
688 key.offset = dst;
689
690 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
691 if (ret < 0)
692 goto out;
693
694 if (ret > 0) {
695 ret = -ENOENT;
696 goto out;
697 }
698
699 ret = btrfs_del_item(trans, quota_root, path);
700out:
701 btrfs_free_path(path);
702 return ret;
703}
704
705static int add_qgroup_item(struct btrfs_trans_handle *trans,
706 struct btrfs_root *quota_root, u64 qgroupid)
707{
708 int ret;
709 struct btrfs_path *path;
710 struct btrfs_qgroup_info_item *qgroup_info;
711 struct btrfs_qgroup_limit_item *qgroup_limit;
712 struct extent_buffer *leaf;
713 struct btrfs_key key;
714
715 if (btrfs_is_testing(quota_root->fs_info))
716 return 0;
717
718 path = btrfs_alloc_path();
719 if (!path)
720 return -ENOMEM;
721
722 key.objectid = 0;
723 key.type = BTRFS_QGROUP_INFO_KEY;
724 key.offset = qgroupid;
725
726 /*
727 * Avoid a transaction abort by catching -EEXIST here. In that
728 * case, we proceed by re-initializing the existing structure
729 * on disk.
730 */
731
732 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
733 sizeof(*qgroup_info));
734 if (ret && ret != -EEXIST)
735 goto out;
736
737 leaf = path->nodes[0];
738 qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
739 struct btrfs_qgroup_info_item);
740 btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
741 btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
742 btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
743 btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
744 btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
745
746 btrfs_mark_buffer_dirty(trans, leaf);
747
748 btrfs_release_path(path);
749
750 key.type = BTRFS_QGROUP_LIMIT_KEY;
751 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
752 sizeof(*qgroup_limit));
753 if (ret && ret != -EEXIST)
754 goto out;
755
756 leaf = path->nodes[0];
757 qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
758 struct btrfs_qgroup_limit_item);
759 btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
760 btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
761 btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
762 btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
763 btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
764
765 btrfs_mark_buffer_dirty(trans, leaf);
766
767 ret = 0;
768out:
769 btrfs_free_path(path);
770 return ret;
771}
772
773static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
774{
775 int ret;
776 struct btrfs_root *quota_root = trans->fs_info->quota_root;
777 struct btrfs_path *path;
778 struct btrfs_key key;
779
780 path = btrfs_alloc_path();
781 if (!path)
782 return -ENOMEM;
783
784 key.objectid = 0;
785 key.type = BTRFS_QGROUP_INFO_KEY;
786 key.offset = qgroupid;
787 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
788 if (ret < 0)
789 goto out;
790
791 if (ret > 0) {
792 ret = -ENOENT;
793 goto out;
794 }
795
796 ret = btrfs_del_item(trans, quota_root, path);
797 if (ret)
798 goto out;
799
800 btrfs_release_path(path);
801
802 key.type = BTRFS_QGROUP_LIMIT_KEY;
803 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
804 if (ret < 0)
805 goto out;
806
807 if (ret > 0) {
808 ret = -ENOENT;
809 goto out;
810 }
811
812 ret = btrfs_del_item(trans, quota_root, path);
813
814out:
815 btrfs_free_path(path);
816 return ret;
817}
818
819static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
820 struct btrfs_qgroup *qgroup)
821{
822 struct btrfs_root *quota_root = trans->fs_info->quota_root;
823 struct btrfs_path *path;
824 struct btrfs_key key;
825 struct extent_buffer *l;
826 struct btrfs_qgroup_limit_item *qgroup_limit;
827 int ret;
828 int slot;
829
830 key.objectid = 0;
831 key.type = BTRFS_QGROUP_LIMIT_KEY;
832 key.offset = qgroup->qgroupid;
833
834 path = btrfs_alloc_path();
835 if (!path)
836 return -ENOMEM;
837
838 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
839 if (ret > 0)
840 ret = -ENOENT;
841
842 if (ret)
843 goto out;
844
845 l = path->nodes[0];
846 slot = path->slots[0];
847 qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
848 btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
849 btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
850 btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
851 btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
852 btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
853
854 btrfs_mark_buffer_dirty(trans, l);
855
856out:
857 btrfs_free_path(path);
858 return ret;
859}
860
861static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
862 struct btrfs_qgroup *qgroup)
863{
864 struct btrfs_fs_info *fs_info = trans->fs_info;
865 struct btrfs_root *quota_root = fs_info->quota_root;
866 struct btrfs_path *path;
867 struct btrfs_key key;
868 struct extent_buffer *l;
869 struct btrfs_qgroup_info_item *qgroup_info;
870 int ret;
871 int slot;
872
873 if (btrfs_is_testing(fs_info))
874 return 0;
875
876 key.objectid = 0;
877 key.type = BTRFS_QGROUP_INFO_KEY;
878 key.offset = qgroup->qgroupid;
879
880 path = btrfs_alloc_path();
881 if (!path)
882 return -ENOMEM;
883
884 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
885 if (ret > 0)
886 ret = -ENOENT;
887
888 if (ret)
889 goto out;
890
891 l = path->nodes[0];
892 slot = path->slots[0];
893 qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
894 btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
895 btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
896 btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
897 btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
898 btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
899
900 btrfs_mark_buffer_dirty(trans, l);
901
902out:
903 btrfs_free_path(path);
904 return ret;
905}
906
907static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
908{
909 struct btrfs_fs_info *fs_info = trans->fs_info;
910 struct btrfs_root *quota_root = fs_info->quota_root;
911 struct btrfs_path *path;
912 struct btrfs_key key;
913 struct extent_buffer *l;
914 struct btrfs_qgroup_status_item *ptr;
915 int ret;
916 int slot;
917
918 key.objectid = 0;
919 key.type = BTRFS_QGROUP_STATUS_KEY;
920 key.offset = 0;
921
922 path = btrfs_alloc_path();
923 if (!path)
924 return -ENOMEM;
925
926 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
927 if (ret > 0)
928 ret = -ENOENT;
929
930 if (ret)
931 goto out;
932
933 l = path->nodes[0];
934 slot = path->slots[0];
935 ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
936 btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags &
937 BTRFS_QGROUP_STATUS_FLAGS_MASK);
938 btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
939 btrfs_set_qgroup_status_rescan(l, ptr,
940 fs_info->qgroup_rescan_progress.objectid);
941
942 btrfs_mark_buffer_dirty(trans, l);
943
944out:
945 btrfs_free_path(path);
946 return ret;
947}
948
949/*
950 * called with qgroup_lock held
951 */
952static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
953 struct btrfs_root *root)
954{
955 struct btrfs_path *path;
956 struct btrfs_key key;
957 struct extent_buffer *leaf = NULL;
958 int ret;
959 int nr = 0;
960
961 path = btrfs_alloc_path();
962 if (!path)
963 return -ENOMEM;
964
965 key.objectid = 0;
966 key.offset = 0;
967 key.type = 0;
968
969 while (1) {
970 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
971 if (ret < 0)
972 goto out;
973 leaf = path->nodes[0];
974 nr = btrfs_header_nritems(leaf);
975 if (!nr)
976 break;
977 /*
978 * delete the leaf one by one
979 * since the whole tree is going
980 * to be deleted.
981 */
982 path->slots[0] = 0;
983 ret = btrfs_del_items(trans, root, path, 0, nr);
984 if (ret)
985 goto out;
986
987 btrfs_release_path(path);
988 }
989 ret = 0;
990out:
991 btrfs_free_path(path);
992 return ret;
993}
994
995int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
996 struct btrfs_ioctl_quota_ctl_args *quota_ctl_args)
997{
998 struct btrfs_root *quota_root;
999 struct btrfs_root *tree_root = fs_info->tree_root;
1000 struct btrfs_path *path = NULL;
1001 struct btrfs_qgroup_status_item *ptr;
1002 struct extent_buffer *leaf;
1003 struct btrfs_key key;
1004 struct btrfs_key found_key;
1005 struct btrfs_qgroup *qgroup = NULL;
1006 struct btrfs_qgroup *prealloc = NULL;
1007 struct btrfs_trans_handle *trans = NULL;
1008 struct ulist *ulist = NULL;
1009 const bool simple = (quota_ctl_args->cmd == BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA);
1010 int ret = 0;
1011 int slot;
1012
1013 /*
1014 * We need to have subvol_sem write locked, to prevent races between
1015 * concurrent tasks trying to enable quotas, because we will unlock
1016 * and relock qgroup_ioctl_lock before setting fs_info->quota_root
1017 * and before setting BTRFS_FS_QUOTA_ENABLED.
1018 */
1019 lockdep_assert_held_write(&fs_info->subvol_sem);
1020
1021 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
1022 btrfs_err(fs_info,
1023 "qgroups are currently unsupported in extent tree v2");
1024 return -EINVAL;
1025 }
1026
1027 mutex_lock(&fs_info->qgroup_ioctl_lock);
1028 if (fs_info->quota_root)
1029 goto out;
1030
1031 ulist = ulist_alloc(GFP_KERNEL);
1032 if (!ulist) {
1033 ret = -ENOMEM;
1034 goto out;
1035 }
1036
1037 ret = btrfs_sysfs_add_qgroups(fs_info);
1038 if (ret < 0)
1039 goto out;
1040
1041 /*
1042 * Unlock qgroup_ioctl_lock before starting the transaction. This is to
1043 * avoid lock acquisition inversion problems (reported by lockdep) between
1044 * qgroup_ioctl_lock and the vfs freeze semaphores, acquired when we
1045 * start a transaction.
1046 * After we started the transaction lock qgroup_ioctl_lock again and
1047 * check if someone else created the quota root in the meanwhile. If so,
1048 * just return success and release the transaction handle.
1049 *
1050 * Also we don't need to worry about someone else calling
1051 * btrfs_sysfs_add_qgroups() after we unlock and getting an error because
1052 * that function returns 0 (success) when the sysfs entries already exist.
1053 */
1054 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1055
1056 /*
1057 * 1 for quota root item
1058 * 1 for BTRFS_QGROUP_STATUS item
1059 *
1060 * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
1061 * per subvolume. However those are not currently reserved since it
1062 * would be a lot of overkill.
1063 */
1064 trans = btrfs_start_transaction(tree_root, 2);
1065
1066 mutex_lock(&fs_info->qgroup_ioctl_lock);
1067 if (IS_ERR(trans)) {
1068 ret = PTR_ERR(trans);
1069 trans = NULL;
1070 goto out;
1071 }
1072
1073 if (fs_info->quota_root)
1074 goto out;
1075
1076 fs_info->qgroup_ulist = ulist;
1077 ulist = NULL;
1078
1079 /*
1080 * initially create the quota tree
1081 */
1082 quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID);
1083 if (IS_ERR(quota_root)) {
1084 ret = PTR_ERR(quota_root);
1085 btrfs_abort_transaction(trans, ret);
1086 goto out;
1087 }
1088
1089 path = btrfs_alloc_path();
1090 if (!path) {
1091 ret = -ENOMEM;
1092 btrfs_abort_transaction(trans, ret);
1093 goto out_free_root;
1094 }
1095
1096 key.objectid = 0;
1097 key.type = BTRFS_QGROUP_STATUS_KEY;
1098 key.offset = 0;
1099
1100 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
1101 sizeof(*ptr));
1102 if (ret) {
1103 btrfs_abort_transaction(trans, ret);
1104 goto out_free_path;
1105 }
1106
1107 leaf = path->nodes[0];
1108 ptr = btrfs_item_ptr(leaf, path->slots[0],
1109 struct btrfs_qgroup_status_item);
1110 btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
1111 btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
1112 fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON;
1113 if (simple) {
1114 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1115 btrfs_set_qgroup_status_enable_gen(leaf, ptr, trans->transid);
1116 } else {
1117 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1118 }
1119 btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags &
1120 BTRFS_QGROUP_STATUS_FLAGS_MASK);
1121 btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
1122
1123 btrfs_mark_buffer_dirty(trans, leaf);
1124
1125 key.objectid = 0;
1126 key.type = BTRFS_ROOT_REF_KEY;
1127 key.offset = 0;
1128
1129 btrfs_release_path(path);
1130 ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
1131 if (ret > 0)
1132 goto out_add_root;
1133 if (ret < 0) {
1134 btrfs_abort_transaction(trans, ret);
1135 goto out_free_path;
1136 }
1137
1138 while (1) {
1139 slot = path->slots[0];
1140 leaf = path->nodes[0];
1141 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1142
1143 if (found_key.type == BTRFS_ROOT_REF_KEY) {
1144
1145 /* Release locks on tree_root before we access quota_root */
1146 btrfs_release_path(path);
1147
1148 /* We should not have a stray @prealloc pointer. */
1149 ASSERT(prealloc == NULL);
1150 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1151 if (!prealloc) {
1152 ret = -ENOMEM;
1153 btrfs_abort_transaction(trans, ret);
1154 goto out_free_path;
1155 }
1156
1157 ret = add_qgroup_item(trans, quota_root,
1158 found_key.offset);
1159 if (ret) {
1160 btrfs_abort_transaction(trans, ret);
1161 goto out_free_path;
1162 }
1163
1164 qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
1165 prealloc = NULL;
1166 if (IS_ERR(qgroup)) {
1167 ret = PTR_ERR(qgroup);
1168 btrfs_abort_transaction(trans, ret);
1169 goto out_free_path;
1170 }
1171 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1172 if (ret < 0) {
1173 btrfs_abort_transaction(trans, ret);
1174 goto out_free_path;
1175 }
1176 ret = btrfs_search_slot_for_read(tree_root, &found_key,
1177 path, 1, 0);
1178 if (ret < 0) {
1179 btrfs_abort_transaction(trans, ret);
1180 goto out_free_path;
1181 }
1182 if (ret > 0) {
1183 /*
1184 * Shouldn't happen, but in case it does we
1185 * don't need to do the btrfs_next_item, just
1186 * continue.
1187 */
1188 continue;
1189 }
1190 }
1191 ret = btrfs_next_item(tree_root, path);
1192 if (ret < 0) {
1193 btrfs_abort_transaction(trans, ret);
1194 goto out_free_path;
1195 }
1196 if (ret)
1197 break;
1198 }
1199
1200out_add_root:
1201 btrfs_release_path(path);
1202 ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1203 if (ret) {
1204 btrfs_abort_transaction(trans, ret);
1205 goto out_free_path;
1206 }
1207
1208 ASSERT(prealloc == NULL);
1209 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1210 if (!prealloc) {
1211 ret = -ENOMEM;
1212 goto out_free_path;
1213 }
1214 qgroup = add_qgroup_rb(fs_info, prealloc, BTRFS_FS_TREE_OBJECTID);
1215 prealloc = NULL;
1216 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1217 if (ret < 0) {
1218 btrfs_abort_transaction(trans, ret);
1219 goto out_free_path;
1220 }
1221
1222 fs_info->qgroup_enable_gen = trans->transid;
1223
1224 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1225 /*
1226 * Commit the transaction while not holding qgroup_ioctl_lock, to avoid
1227 * a deadlock with tasks concurrently doing other qgroup operations, such
1228 * adding/removing qgroups or adding/deleting qgroup relations for example,
1229 * because all qgroup operations first start or join a transaction and then
1230 * lock the qgroup_ioctl_lock mutex.
1231 * We are safe from a concurrent task trying to enable quotas, by calling
1232 * this function, since we are serialized by fs_info->subvol_sem.
1233 */
1234 ret = btrfs_commit_transaction(trans);
1235 trans = NULL;
1236 mutex_lock(&fs_info->qgroup_ioctl_lock);
1237 if (ret)
1238 goto out_free_path;
1239
1240 /*
1241 * Set quota enabled flag after committing the transaction, to avoid
1242 * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1243 * creation.
1244 */
1245 spin_lock(&fs_info->qgroup_lock);
1246 fs_info->quota_root = quota_root;
1247 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1248 if (simple)
1249 btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA);
1250 spin_unlock(&fs_info->qgroup_lock);
1251
1252 /* Skip rescan for simple qgroups. */
1253 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
1254 goto out_free_path;
1255
1256 ret = qgroup_rescan_init(fs_info, 0, 1);
1257 if (!ret) {
1258 qgroup_rescan_zero_tracking(fs_info);
1259 fs_info->qgroup_rescan_running = true;
1260 btrfs_queue_work(fs_info->qgroup_rescan_workers,
1261 &fs_info->qgroup_rescan_work);
1262 } else {
1263 /*
1264 * We have set both BTRFS_FS_QUOTA_ENABLED and
1265 * BTRFS_QGROUP_STATUS_FLAG_ON, so we can only fail with
1266 * -EINPROGRESS. That can happen because someone started the
1267 * rescan worker by calling quota rescan ioctl before we
1268 * attempted to initialize the rescan worker. Failure due to
1269 * quotas disabled in the meanwhile is not possible, because
1270 * we are holding a write lock on fs_info->subvol_sem, which
1271 * is also acquired when disabling quotas.
1272 * Ignore such error, and any other error would need to undo
1273 * everything we did in the transaction we just committed.
1274 */
1275 ASSERT(ret == -EINPROGRESS);
1276 ret = 0;
1277 }
1278
1279out_free_path:
1280 btrfs_free_path(path);
1281out_free_root:
1282 if (ret)
1283 btrfs_put_root(quota_root);
1284out:
1285 if (ret) {
1286 ulist_free(fs_info->qgroup_ulist);
1287 fs_info->qgroup_ulist = NULL;
1288 btrfs_sysfs_del_qgroups(fs_info);
1289 }
1290 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1291 if (ret && trans)
1292 btrfs_end_transaction(trans);
1293 else if (trans)
1294 ret = btrfs_end_transaction(trans);
1295 ulist_free(ulist);
1296 kfree(prealloc);
1297 return ret;
1298}
1299
1300/*
1301 * It is possible to have outstanding ordered extents which reserved bytes
1302 * before we disabled. We need to fully flush delalloc, ordered extents, and a
1303 * commit to ensure that we don't leak such reservations, only to have them
1304 * come back if we re-enable.
1305 *
1306 * - enable simple quotas
1307 * - reserve space
1308 * - release it, store rsv_bytes in OE
1309 * - disable quotas
1310 * - enable simple quotas (qgroup rsv are all 0)
1311 * - OE finishes
1312 * - run delayed refs
1313 * - free rsv_bytes, resulting in miscounting or even underflow
1314 */
1315static int flush_reservations(struct btrfs_fs_info *fs_info)
1316{
1317 struct btrfs_trans_handle *trans;
1318 int ret;
1319
1320 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
1321 if (ret)
1322 return ret;
1323 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1324 trans = btrfs_join_transaction(fs_info->tree_root);
1325 if (IS_ERR(trans))
1326 return PTR_ERR(trans);
1327 btrfs_commit_transaction(trans);
1328
1329 return ret;
1330}
1331
1332int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
1333{
1334 struct btrfs_root *quota_root;
1335 struct btrfs_trans_handle *trans = NULL;
1336 int ret = 0;
1337
1338 /*
1339 * We need to have subvol_sem write locked to prevent races with
1340 * snapshot creation.
1341 */
1342 lockdep_assert_held_write(&fs_info->subvol_sem);
1343
1344 /*
1345 * Lock the cleaner mutex to prevent races with concurrent relocation,
1346 * because relocation may be building backrefs for blocks of the quota
1347 * root while we are deleting the root. This is like dropping fs roots
1348 * of deleted snapshots/subvolumes, we need the same protection.
1349 *
1350 * This also prevents races between concurrent tasks trying to disable
1351 * quotas, because we will unlock and relock qgroup_ioctl_lock across
1352 * BTRFS_FS_QUOTA_ENABLED changes.
1353 */
1354 mutex_lock(&fs_info->cleaner_mutex);
1355
1356 mutex_lock(&fs_info->qgroup_ioctl_lock);
1357 if (!fs_info->quota_root)
1358 goto out;
1359
1360 /*
1361 * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to
1362 * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs
1363 * to lock that mutex while holding a transaction handle and the rescan
1364 * worker needs to commit a transaction.
1365 */
1366 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1367
1368 /*
1369 * Request qgroup rescan worker to complete and wait for it. This wait
1370 * must be done before transaction start for quota disable since it may
1371 * deadlock with transaction by the qgroup rescan worker.
1372 */
1373 clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1374 btrfs_qgroup_wait_for_completion(fs_info, false);
1375
1376 ret = flush_reservations(fs_info);
1377 if (ret)
1378 goto out_unlock_cleaner;
1379
1380 /*
1381 * 1 For the root item
1382 *
1383 * We should also reserve enough items for the quota tree deletion in
1384 * btrfs_clean_quota_tree but this is not done.
1385 *
1386 * Also, we must always start a transaction without holding the mutex
1387 * qgroup_ioctl_lock, see btrfs_quota_enable().
1388 */
1389 trans = btrfs_start_transaction(fs_info->tree_root, 1);
1390
1391 mutex_lock(&fs_info->qgroup_ioctl_lock);
1392 if (IS_ERR(trans)) {
1393 ret = PTR_ERR(trans);
1394 trans = NULL;
1395 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1396 goto out;
1397 }
1398
1399 if (!fs_info->quota_root)
1400 goto out;
1401
1402 spin_lock(&fs_info->qgroup_lock);
1403 quota_root = fs_info->quota_root;
1404 fs_info->quota_root = NULL;
1405 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1406 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1407 fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1408 spin_unlock(&fs_info->qgroup_lock);
1409
1410 btrfs_free_qgroup_config(fs_info);
1411
1412 ret = btrfs_clean_quota_tree(trans, quota_root);
1413 if (ret) {
1414 btrfs_abort_transaction(trans, ret);
1415 goto out;
1416 }
1417
1418 ret = btrfs_del_root(trans, "a_root->root_key);
1419 if (ret) {
1420 btrfs_abort_transaction(trans, ret);
1421 goto out;
1422 }
1423
1424 spin_lock(&fs_info->trans_lock);
1425 list_del("a_root->dirty_list);
1426 spin_unlock(&fs_info->trans_lock);
1427
1428 btrfs_tree_lock(quota_root->node);
1429 btrfs_clear_buffer_dirty(trans, quota_root->node);
1430 btrfs_tree_unlock(quota_root->node);
1431 btrfs_free_tree_block(trans, btrfs_root_id(quota_root),
1432 quota_root->node, 0, 1);
1433
1434 btrfs_put_root(quota_root);
1435
1436out:
1437 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1438 if (ret && trans)
1439 btrfs_end_transaction(trans);
1440 else if (trans)
1441 ret = btrfs_commit_transaction(trans);
1442out_unlock_cleaner:
1443 mutex_unlock(&fs_info->cleaner_mutex);
1444
1445 return ret;
1446}
1447
1448static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1449 struct btrfs_qgroup *qgroup)
1450{
1451 if (list_empty(&qgroup->dirty))
1452 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1453}
1454
1455static void qgroup_iterator_add(struct list_head *head, struct btrfs_qgroup *qgroup)
1456{
1457 if (!list_empty(&qgroup->iterator))
1458 return;
1459
1460 list_add_tail(&qgroup->iterator, head);
1461}
1462
1463static void qgroup_iterator_clean(struct list_head *head)
1464{
1465 while (!list_empty(head)) {
1466 struct btrfs_qgroup *qgroup;
1467
1468 qgroup = list_first_entry(head, struct btrfs_qgroup, iterator);
1469 list_del_init(&qgroup->iterator);
1470 }
1471}
1472
1473/*
1474 * The easy accounting, we're updating qgroup relationship whose child qgroup
1475 * only has exclusive extents.
1476 *
1477 * In this case, all exclusive extents will also be exclusive for parent, so
1478 * excl/rfer just get added/removed.
1479 *
1480 * So is qgroup reservation space, which should also be added/removed to
1481 * parent.
1482 * Or when child tries to release reservation space, parent will underflow its
1483 * reservation (for relationship adding case).
1484 *
1485 * Caller should hold fs_info->qgroup_lock.
1486 */
1487static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, u64 ref_root,
1488 struct btrfs_qgroup *src, int sign)
1489{
1490 struct btrfs_qgroup *qgroup;
1491 struct btrfs_qgroup *cur;
1492 LIST_HEAD(qgroup_list);
1493 u64 num_bytes = src->excl;
1494 int ret = 0;
1495
1496 qgroup = find_qgroup_rb(fs_info, ref_root);
1497 if (!qgroup)
1498 goto out;
1499
1500 qgroup_iterator_add(&qgroup_list, qgroup);
1501 list_for_each_entry(cur, &qgroup_list, iterator) {
1502 struct btrfs_qgroup_list *glist;
1503
1504 qgroup->rfer += sign * num_bytes;
1505 qgroup->rfer_cmpr += sign * num_bytes;
1506
1507 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1508 qgroup->excl += sign * num_bytes;
1509 qgroup->excl_cmpr += sign * num_bytes;
1510
1511 if (sign > 0)
1512 qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1513 else
1514 qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1515 qgroup_dirty(fs_info, qgroup);
1516
1517 /* Append parent qgroups to @qgroup_list. */
1518 list_for_each_entry(glist, &qgroup->groups, next_group)
1519 qgroup_iterator_add(&qgroup_list, glist->group);
1520 }
1521 ret = 0;
1522out:
1523 qgroup_iterator_clean(&qgroup_list);
1524 return ret;
1525}
1526
1527
1528/*
1529 * Quick path for updating qgroup with only excl refs.
1530 *
1531 * In that case, just update all parent will be enough.
1532 * Or we needs to do a full rescan.
1533 * Caller should also hold fs_info->qgroup_lock.
1534 *
1535 * Return 0 for quick update, return >0 for need to full rescan
1536 * and mark INCONSISTENT flag.
1537 * Return < 0 for other error.
1538 */
1539static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1540 u64 src, u64 dst, int sign)
1541{
1542 struct btrfs_qgroup *qgroup;
1543 int ret = 1;
1544 int err = 0;
1545
1546 qgroup = find_qgroup_rb(fs_info, src);
1547 if (!qgroup)
1548 goto out;
1549 if (qgroup->excl == qgroup->rfer) {
1550 ret = 0;
1551 err = __qgroup_excl_accounting(fs_info, dst, qgroup, sign);
1552 if (err < 0) {
1553 ret = err;
1554 goto out;
1555 }
1556 }
1557out:
1558 if (ret)
1559 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1560 return ret;
1561}
1562
1563int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst)
1564{
1565 struct btrfs_fs_info *fs_info = trans->fs_info;
1566 struct btrfs_qgroup *parent;
1567 struct btrfs_qgroup *member;
1568 struct btrfs_qgroup_list *list;
1569 struct btrfs_qgroup_list *prealloc = NULL;
1570 int ret = 0;
1571
1572 /* Check the level of src and dst first */
1573 if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1574 return -EINVAL;
1575
1576 mutex_lock(&fs_info->qgroup_ioctl_lock);
1577 if (!fs_info->quota_root) {
1578 ret = -ENOTCONN;
1579 goto out;
1580 }
1581 member = find_qgroup_rb(fs_info, src);
1582 parent = find_qgroup_rb(fs_info, dst);
1583 if (!member || !parent) {
1584 ret = -EINVAL;
1585 goto out;
1586 }
1587
1588 /* check if such qgroup relation exist firstly */
1589 list_for_each_entry(list, &member->groups, next_group) {
1590 if (list->group == parent) {
1591 ret = -EEXIST;
1592 goto out;
1593 }
1594 }
1595
1596 prealloc = kzalloc(sizeof(*list), GFP_NOFS);
1597 if (!prealloc) {
1598 ret = -ENOMEM;
1599 goto out;
1600 }
1601 ret = add_qgroup_relation_item(trans, src, dst);
1602 if (ret)
1603 goto out;
1604
1605 ret = add_qgroup_relation_item(trans, dst, src);
1606 if (ret) {
1607 del_qgroup_relation_item(trans, src, dst);
1608 goto out;
1609 }
1610
1611 spin_lock(&fs_info->qgroup_lock);
1612 ret = __add_relation_rb(prealloc, member, parent);
1613 prealloc = NULL;
1614 if (ret < 0) {
1615 spin_unlock(&fs_info->qgroup_lock);
1616 goto out;
1617 }
1618 ret = quick_update_accounting(fs_info, src, dst, 1);
1619 spin_unlock(&fs_info->qgroup_lock);
1620out:
1621 kfree(prealloc);
1622 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1623 return ret;
1624}
1625
1626static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1627 u64 dst)
1628{
1629 struct btrfs_fs_info *fs_info = trans->fs_info;
1630 struct btrfs_qgroup *parent;
1631 struct btrfs_qgroup *member;
1632 struct btrfs_qgroup_list *list;
1633 bool found = false;
1634 int ret = 0;
1635 int ret2;
1636
1637 if (!fs_info->quota_root) {
1638 ret = -ENOTCONN;
1639 goto out;
1640 }
1641
1642 member = find_qgroup_rb(fs_info, src);
1643 parent = find_qgroup_rb(fs_info, dst);
1644 /*
1645 * The parent/member pair doesn't exist, then try to delete the dead
1646 * relation items only.
1647 */
1648 if (!member || !parent)
1649 goto delete_item;
1650
1651 /* check if such qgroup relation exist firstly */
1652 list_for_each_entry(list, &member->groups, next_group) {
1653 if (list->group == parent) {
1654 found = true;
1655 break;
1656 }
1657 }
1658
1659delete_item:
1660 ret = del_qgroup_relation_item(trans, src, dst);
1661 if (ret < 0 && ret != -ENOENT)
1662 goto out;
1663 ret2 = del_qgroup_relation_item(trans, dst, src);
1664 if (ret2 < 0 && ret2 != -ENOENT)
1665 goto out;
1666
1667 /* At least one deletion succeeded, return 0 */
1668 if (!ret || !ret2)
1669 ret = 0;
1670
1671 if (found) {
1672 spin_lock(&fs_info->qgroup_lock);
1673 del_relation_rb(fs_info, src, dst);
1674 ret = quick_update_accounting(fs_info, src, dst, -1);
1675 spin_unlock(&fs_info->qgroup_lock);
1676 }
1677out:
1678 return ret;
1679}
1680
1681int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1682 u64 dst)
1683{
1684 struct btrfs_fs_info *fs_info = trans->fs_info;
1685 int ret = 0;
1686
1687 mutex_lock(&fs_info->qgroup_ioctl_lock);
1688 ret = __del_qgroup_relation(trans, src, dst);
1689 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1690
1691 return ret;
1692}
1693
1694int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1695{
1696 struct btrfs_fs_info *fs_info = trans->fs_info;
1697 struct btrfs_root *quota_root;
1698 struct btrfs_qgroup *qgroup;
1699 struct btrfs_qgroup *prealloc = NULL;
1700 int ret = 0;
1701
1702 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
1703 return 0;
1704
1705 mutex_lock(&fs_info->qgroup_ioctl_lock);
1706 if (!fs_info->quota_root) {
1707 ret = -ENOTCONN;
1708 goto out;
1709 }
1710 quota_root = fs_info->quota_root;
1711 qgroup = find_qgroup_rb(fs_info, qgroupid);
1712 if (qgroup) {
1713 ret = -EEXIST;
1714 goto out;
1715 }
1716
1717 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1718 if (!prealloc) {
1719 ret = -ENOMEM;
1720 goto out;
1721 }
1722
1723 ret = add_qgroup_item(trans, quota_root, qgroupid);
1724 if (ret)
1725 goto out;
1726
1727 spin_lock(&fs_info->qgroup_lock);
1728 qgroup = add_qgroup_rb(fs_info, prealloc, qgroupid);
1729 spin_unlock(&fs_info->qgroup_lock);
1730 prealloc = NULL;
1731
1732 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1733out:
1734 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1735 kfree(prealloc);
1736 return ret;
1737}
1738
1739static bool qgroup_has_usage(struct btrfs_qgroup *qgroup)
1740{
1741 return (qgroup->rfer > 0 || qgroup->rfer_cmpr > 0 ||
1742 qgroup->excl > 0 || qgroup->excl_cmpr > 0 ||
1743 qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] > 0 ||
1744 qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] > 0 ||
1745 qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > 0);
1746}
1747
1748int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1749{
1750 struct btrfs_fs_info *fs_info = trans->fs_info;
1751 struct btrfs_qgroup *qgroup;
1752 struct btrfs_qgroup_list *list;
1753 int ret = 0;
1754
1755 mutex_lock(&fs_info->qgroup_ioctl_lock);
1756 if (!fs_info->quota_root) {
1757 ret = -ENOTCONN;
1758 goto out;
1759 }
1760
1761 qgroup = find_qgroup_rb(fs_info, qgroupid);
1762 if (!qgroup) {
1763 ret = -ENOENT;
1764 goto out;
1765 }
1766
1767 if (is_fstree(qgroupid) && qgroup_has_usage(qgroup)) {
1768 ret = -EBUSY;
1769 goto out;
1770 }
1771
1772 /* Check if there are no children of this qgroup */
1773 if (!list_empty(&qgroup->members)) {
1774 ret = -EBUSY;
1775 goto out;
1776 }
1777
1778 ret = del_qgroup_item(trans, qgroupid);
1779 if (ret && ret != -ENOENT)
1780 goto out;
1781
1782 while (!list_empty(&qgroup->groups)) {
1783 list = list_first_entry(&qgroup->groups,
1784 struct btrfs_qgroup_list, next_group);
1785 ret = __del_qgroup_relation(trans, qgroupid,
1786 list->group->qgroupid);
1787 if (ret)
1788 goto out;
1789 }
1790
1791 spin_lock(&fs_info->qgroup_lock);
1792 del_qgroup_rb(fs_info, qgroupid);
1793 spin_unlock(&fs_info->qgroup_lock);
1794
1795 /*
1796 * Remove the qgroup from sysfs now without holding the qgroup_lock
1797 * spinlock, since the sysfs_remove_group() function needs to take
1798 * the mutex kernfs_mutex through kernfs_remove_by_name_ns().
1799 */
1800 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1801 kfree(qgroup);
1802out:
1803 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1804 return ret;
1805}
1806
1807int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
1808 struct btrfs_qgroup_limit *limit)
1809{
1810 struct btrfs_fs_info *fs_info = trans->fs_info;
1811 struct btrfs_qgroup *qgroup;
1812 int ret = 0;
1813 /* Sometimes we would want to clear the limit on this qgroup.
1814 * To meet this requirement, we treat the -1 as a special value
1815 * which tell kernel to clear the limit on this qgroup.
1816 */
1817 const u64 CLEAR_VALUE = -1;
1818
1819 mutex_lock(&fs_info->qgroup_ioctl_lock);
1820 if (!fs_info->quota_root) {
1821 ret = -ENOTCONN;
1822 goto out;
1823 }
1824
1825 qgroup = find_qgroup_rb(fs_info, qgroupid);
1826 if (!qgroup) {
1827 ret = -ENOENT;
1828 goto out;
1829 }
1830
1831 spin_lock(&fs_info->qgroup_lock);
1832 if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1833 if (limit->max_rfer == CLEAR_VALUE) {
1834 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1835 limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1836 qgroup->max_rfer = 0;
1837 } else {
1838 qgroup->max_rfer = limit->max_rfer;
1839 }
1840 }
1841 if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1842 if (limit->max_excl == CLEAR_VALUE) {
1843 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1844 limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1845 qgroup->max_excl = 0;
1846 } else {
1847 qgroup->max_excl = limit->max_excl;
1848 }
1849 }
1850 if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1851 if (limit->rsv_rfer == CLEAR_VALUE) {
1852 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1853 limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1854 qgroup->rsv_rfer = 0;
1855 } else {
1856 qgroup->rsv_rfer = limit->rsv_rfer;
1857 }
1858 }
1859 if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1860 if (limit->rsv_excl == CLEAR_VALUE) {
1861 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1862 limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1863 qgroup->rsv_excl = 0;
1864 } else {
1865 qgroup->rsv_excl = limit->rsv_excl;
1866 }
1867 }
1868 qgroup->lim_flags |= limit->flags;
1869
1870 spin_unlock(&fs_info->qgroup_lock);
1871
1872 ret = update_qgroup_limit_item(trans, qgroup);
1873 if (ret) {
1874 qgroup_mark_inconsistent(fs_info);
1875 btrfs_info(fs_info, "unable to update quota limit for %llu",
1876 qgroupid);
1877 }
1878
1879out:
1880 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1881 return ret;
1882}
1883
1884/*
1885 * Inform qgroup to trace one dirty extent, its info is recorded in @record.
1886 * So qgroup can account it at transaction committing time.
1887 *
1888 * No lock version, caller must acquire delayed ref lock and allocated memory,
1889 * then call btrfs_qgroup_trace_extent_post() after exiting lock context.
1890 *
1891 * Return 0 for success insert
1892 * Return >0 for existing record, caller can free @record safely.
1893 * Error is not possible
1894 */
1895int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1896 struct btrfs_delayed_ref_root *delayed_refs,
1897 struct btrfs_qgroup_extent_record *record)
1898{
1899 struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1900 struct rb_node *parent_node = NULL;
1901 struct btrfs_qgroup_extent_record *entry;
1902 u64 bytenr = record->bytenr;
1903
1904 if (!btrfs_qgroup_full_accounting(fs_info))
1905 return 1;
1906
1907 lockdep_assert_held(&delayed_refs->lock);
1908 trace_btrfs_qgroup_trace_extent(fs_info, record);
1909
1910 while (*p) {
1911 parent_node = *p;
1912 entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1913 node);
1914 if (bytenr < entry->bytenr) {
1915 p = &(*p)->rb_left;
1916 } else if (bytenr > entry->bytenr) {
1917 p = &(*p)->rb_right;
1918 } else {
1919 if (record->data_rsv && !entry->data_rsv) {
1920 entry->data_rsv = record->data_rsv;
1921 entry->data_rsv_refroot =
1922 record->data_rsv_refroot;
1923 }
1924 return 1;
1925 }
1926 }
1927
1928 rb_link_node(&record->node, parent_node, p);
1929 rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1930 return 0;
1931}
1932
1933/*
1934 * Post handler after qgroup_trace_extent_nolock().
1935 *
1936 * NOTE: Current qgroup does the expensive backref walk at transaction
1937 * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming
1938 * new transaction.
1939 * This is designed to allow btrfs_find_all_roots() to get correct new_roots
1940 * result.
1941 *
1942 * However for old_roots there is no need to do backref walk at that time,
1943 * since we search commit roots to walk backref and result will always be
1944 * correct.
1945 *
1946 * Due to the nature of no lock version, we can't do backref there.
1947 * So we must call btrfs_qgroup_trace_extent_post() after exiting
1948 * spinlock context.
1949 *
1950 * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result
1951 * using current root, then we can move all expensive backref walk out of
1952 * transaction committing, but not now as qgroup accounting will be wrong again.
1953 */
1954int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
1955 struct btrfs_qgroup_extent_record *qrecord)
1956{
1957 struct btrfs_backref_walk_ctx ctx = { 0 };
1958 int ret;
1959
1960 if (!btrfs_qgroup_full_accounting(trans->fs_info))
1961 return 0;
1962 /*
1963 * We are always called in a context where we are already holding a
1964 * transaction handle. Often we are called when adding a data delayed
1965 * reference from btrfs_truncate_inode_items() (truncating or unlinking),
1966 * in which case we will be holding a write lock on extent buffer from a
1967 * subvolume tree. In this case we can't allow btrfs_find_all_roots() to
1968 * acquire fs_info->commit_root_sem, because that is a higher level lock
1969 * that must be acquired before locking any extent buffers.
1970 *
1971 * So we want btrfs_find_all_roots() to not acquire the commit_root_sem
1972 * but we can't pass it a non-NULL transaction handle, because otherwise
1973 * it would not use commit roots and would lock extent buffers, causing
1974 * a deadlock if it ends up trying to read lock the same extent buffer
1975 * that was previously write locked at btrfs_truncate_inode_items().
1976 *
1977 * So pass a NULL transaction handle to btrfs_find_all_roots() and
1978 * explicitly tell it to not acquire the commit_root_sem - if we are
1979 * holding a transaction handle we don't need its protection.
1980 */
1981 ASSERT(trans != NULL);
1982
1983 if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
1984 return 0;
1985
1986 ctx.bytenr = qrecord->bytenr;
1987 ctx.fs_info = trans->fs_info;
1988
1989 ret = btrfs_find_all_roots(&ctx, true);
1990 if (ret < 0) {
1991 qgroup_mark_inconsistent(trans->fs_info);
1992 btrfs_warn(trans->fs_info,
1993"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1994 ret);
1995 return 0;
1996 }
1997
1998 /*
1999 * Here we don't need to get the lock of
2000 * trans->transaction->delayed_refs, since inserted qrecord won't
2001 * be deleted, only qrecord->node may be modified (new qrecord insert)
2002 *
2003 * So modifying qrecord->old_roots is safe here
2004 */
2005 qrecord->old_roots = ctx.roots;
2006 return 0;
2007}
2008
2009/*
2010 * Inform qgroup to trace one dirty extent, specified by @bytenr and
2011 * @num_bytes.
2012 * So qgroup can account it at commit trans time.
2013 *
2014 * Better encapsulated version, with memory allocation and backref walk for
2015 * commit roots.
2016 * So this can sleep.
2017 *
2018 * Return 0 if the operation is done.
2019 * Return <0 for error, like memory allocation failure or invalid parameter
2020 * (NULL trans)
2021 */
2022int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2023 u64 num_bytes)
2024{
2025 struct btrfs_fs_info *fs_info = trans->fs_info;
2026 struct btrfs_qgroup_extent_record *record;
2027 struct btrfs_delayed_ref_root *delayed_refs;
2028 int ret;
2029
2030 if (!btrfs_qgroup_full_accounting(fs_info) || bytenr == 0 || num_bytes == 0)
2031 return 0;
2032 record = kzalloc(sizeof(*record), GFP_NOFS);
2033 if (!record)
2034 return -ENOMEM;
2035
2036 delayed_refs = &trans->transaction->delayed_refs;
2037 record->bytenr = bytenr;
2038 record->num_bytes = num_bytes;
2039 record->old_roots = NULL;
2040
2041 spin_lock(&delayed_refs->lock);
2042 ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
2043 spin_unlock(&delayed_refs->lock);
2044 if (ret > 0) {
2045 kfree(record);
2046 return 0;
2047 }
2048 return btrfs_qgroup_trace_extent_post(trans, record);
2049}
2050
2051/*
2052 * Inform qgroup to trace all leaf items of data
2053 *
2054 * Return 0 for success
2055 * Return <0 for error(ENOMEM)
2056 */
2057int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
2058 struct extent_buffer *eb)
2059{
2060 struct btrfs_fs_info *fs_info = trans->fs_info;
2061 int nr = btrfs_header_nritems(eb);
2062 int i, extent_type, ret;
2063 struct btrfs_key key;
2064 struct btrfs_file_extent_item *fi;
2065 u64 bytenr, num_bytes;
2066
2067 /* We can be called directly from walk_up_proc() */
2068 if (!btrfs_qgroup_full_accounting(fs_info))
2069 return 0;
2070
2071 for (i = 0; i < nr; i++) {
2072 btrfs_item_key_to_cpu(eb, &key, i);
2073
2074 if (key.type != BTRFS_EXTENT_DATA_KEY)
2075 continue;
2076
2077 fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2078 /* filter out non qgroup-accountable extents */
2079 extent_type = btrfs_file_extent_type(eb, fi);
2080
2081 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
2082 continue;
2083
2084 bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
2085 if (!bytenr)
2086 continue;
2087
2088 num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
2089
2090 ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes);
2091 if (ret)
2092 return ret;
2093 }
2094 cond_resched();
2095 return 0;
2096}
2097
2098/*
2099 * Walk up the tree from the bottom, freeing leaves and any interior
2100 * nodes which have had all slots visited. If a node (leaf or
2101 * interior) is freed, the node above it will have it's slot
2102 * incremented. The root node will never be freed.
2103 *
2104 * At the end of this function, we should have a path which has all
2105 * slots incremented to the next position for a search. If we need to
2106 * read a new node it will be NULL and the node above it will have the
2107 * correct slot selected for a later read.
2108 *
2109 * If we increment the root nodes slot counter past the number of
2110 * elements, 1 is returned to signal completion of the search.
2111 */
2112static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
2113{
2114 int level = 0;
2115 int nr, slot;
2116 struct extent_buffer *eb;
2117
2118 if (root_level == 0)
2119 return 1;
2120
2121 while (level <= root_level) {
2122 eb = path->nodes[level];
2123 nr = btrfs_header_nritems(eb);
2124 path->slots[level]++;
2125 slot = path->slots[level];
2126 if (slot >= nr || level == 0) {
2127 /*
2128 * Don't free the root - we will detect this
2129 * condition after our loop and return a
2130 * positive value for caller to stop walking the tree.
2131 */
2132 if (level != root_level) {
2133 btrfs_tree_unlock_rw(eb, path->locks[level]);
2134 path->locks[level] = 0;
2135
2136 free_extent_buffer(eb);
2137 path->nodes[level] = NULL;
2138 path->slots[level] = 0;
2139 }
2140 } else {
2141 /*
2142 * We have a valid slot to walk back down
2143 * from. Stop here so caller can process these
2144 * new nodes.
2145 */
2146 break;
2147 }
2148
2149 level++;
2150 }
2151
2152 eb = path->nodes[root_level];
2153 if (path->slots[root_level] >= btrfs_header_nritems(eb))
2154 return 1;
2155
2156 return 0;
2157}
2158
2159/*
2160 * Helper function to trace a subtree tree block swap.
2161 *
2162 * The swap will happen in highest tree block, but there may be a lot of
2163 * tree blocks involved.
2164 *
2165 * For example:
2166 * OO = Old tree blocks
2167 * NN = New tree blocks allocated during balance
2168 *
2169 * File tree (257) Reloc tree for 257
2170 * L2 OO NN
2171 * / \ / \
2172 * L1 OO OO (a) OO NN (a)
2173 * / \ / \ / \ / \
2174 * L0 OO OO OO OO OO OO NN NN
2175 * (b) (c) (b) (c)
2176 *
2177 * When calling qgroup_trace_extent_swap(), we will pass:
2178 * @src_eb = OO(a)
2179 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
2180 * @dst_level = 0
2181 * @root_level = 1
2182 *
2183 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
2184 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
2185 *
2186 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
2187 *
2188 * 1) Tree search from @src_eb
2189 * It should acts as a simplified btrfs_search_slot().
2190 * The key for search can be extracted from @dst_path->nodes[dst_level]
2191 * (first key).
2192 *
2193 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
2194 * NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
2195 * They should be marked during previous (@dst_level = 1) iteration.
2196 *
2197 * 3) Mark file extents in leaves dirty
2198 * We don't have good way to pick out new file extents only.
2199 * So we still follow the old method by scanning all file extents in
2200 * the leave.
2201 *
2202 * This function can free us from keeping two paths, thus later we only need
2203 * to care about how to iterate all new tree blocks in reloc tree.
2204 */
2205static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
2206 struct extent_buffer *src_eb,
2207 struct btrfs_path *dst_path,
2208 int dst_level, int root_level,
2209 bool trace_leaf)
2210{
2211 struct btrfs_key key;
2212 struct btrfs_path *src_path;
2213 struct btrfs_fs_info *fs_info = trans->fs_info;
2214 u32 nodesize = fs_info->nodesize;
2215 int cur_level = root_level;
2216 int ret;
2217
2218 BUG_ON(dst_level > root_level);
2219 /* Level mismatch */
2220 if (btrfs_header_level(src_eb) != root_level)
2221 return -EINVAL;
2222
2223 src_path = btrfs_alloc_path();
2224 if (!src_path) {
2225 ret = -ENOMEM;
2226 goto out;
2227 }
2228
2229 if (dst_level)
2230 btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2231 else
2232 btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2233
2234 /* For src_path */
2235 atomic_inc(&src_eb->refs);
2236 src_path->nodes[root_level] = src_eb;
2237 src_path->slots[root_level] = dst_path->slots[root_level];
2238 src_path->locks[root_level] = 0;
2239
2240 /* A simplified version of btrfs_search_slot() */
2241 while (cur_level >= dst_level) {
2242 struct btrfs_key src_key;
2243 struct btrfs_key dst_key;
2244
2245 if (src_path->nodes[cur_level] == NULL) {
2246 struct extent_buffer *eb;
2247 int parent_slot;
2248
2249 eb = src_path->nodes[cur_level + 1];
2250 parent_slot = src_path->slots[cur_level + 1];
2251
2252 eb = btrfs_read_node_slot(eb, parent_slot);
2253 if (IS_ERR(eb)) {
2254 ret = PTR_ERR(eb);
2255 goto out;
2256 }
2257
2258 src_path->nodes[cur_level] = eb;
2259
2260 btrfs_tree_read_lock(eb);
2261 src_path->locks[cur_level] = BTRFS_READ_LOCK;
2262 }
2263
2264 src_path->slots[cur_level] = dst_path->slots[cur_level];
2265 if (cur_level) {
2266 btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
2267 &dst_key, dst_path->slots[cur_level]);
2268 btrfs_node_key_to_cpu(src_path->nodes[cur_level],
2269 &src_key, src_path->slots[cur_level]);
2270 } else {
2271 btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
2272 &dst_key, dst_path->slots[cur_level]);
2273 btrfs_item_key_to_cpu(src_path->nodes[cur_level],
2274 &src_key, src_path->slots[cur_level]);
2275 }
2276 /* Content mismatch, something went wrong */
2277 if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
2278 ret = -ENOENT;
2279 goto out;
2280 }
2281 cur_level--;
2282 }
2283
2284 /*
2285 * Now both @dst_path and @src_path have been populated, record the tree
2286 * blocks for qgroup accounting.
2287 */
2288 ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
2289 nodesize);
2290 if (ret < 0)
2291 goto out;
2292 ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start,
2293 nodesize);
2294 if (ret < 0)
2295 goto out;
2296
2297 /* Record leaf file extents */
2298 if (dst_level == 0 && trace_leaf) {
2299 ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
2300 if (ret < 0)
2301 goto out;
2302 ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
2303 }
2304out:
2305 btrfs_free_path(src_path);
2306 return ret;
2307}
2308
2309/*
2310 * Helper function to do recursive generation-aware depth-first search, to
2311 * locate all new tree blocks in a subtree of reloc tree.
2312 *
2313 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
2314 * reloc tree
2315 * L2 NN (a)
2316 * / \
2317 * L1 OO NN (b)
2318 * / \ / \
2319 * L0 OO OO OO NN
2320 * (c) (d)
2321 * If we pass:
2322 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
2323 * @cur_level = 1
2324 * @root_level = 1
2325 *
2326 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
2327 * above tree blocks along with their counter parts in file tree.
2328 * While during search, old tree blocks OO(c) will be skipped as tree block swap
2329 * won't affect OO(c).
2330 */
2331static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
2332 struct extent_buffer *src_eb,
2333 struct btrfs_path *dst_path,
2334 int cur_level, int root_level,
2335 u64 last_snapshot, bool trace_leaf)
2336{
2337 struct btrfs_fs_info *fs_info = trans->fs_info;
2338 struct extent_buffer *eb;
2339 bool need_cleanup = false;
2340 int ret = 0;
2341 int i;
2342
2343 /* Level sanity check */
2344 if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
2345 root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
2346 root_level < cur_level) {
2347 btrfs_err_rl(fs_info,
2348 "%s: bad levels, cur_level=%d root_level=%d",
2349 __func__, cur_level, root_level);
2350 return -EUCLEAN;
2351 }
2352
2353 /* Read the tree block if needed */
2354 if (dst_path->nodes[cur_level] == NULL) {
2355 int parent_slot;
2356 u64 child_gen;
2357
2358 /*
2359 * dst_path->nodes[root_level] must be initialized before
2360 * calling this function.
2361 */
2362 if (cur_level == root_level) {
2363 btrfs_err_rl(fs_info,
2364 "%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
2365 __func__, root_level, root_level, cur_level);
2366 return -EUCLEAN;
2367 }
2368
2369 /*
2370 * We need to get child blockptr/gen from parent before we can
2371 * read it.
2372 */
2373 eb = dst_path->nodes[cur_level + 1];
2374 parent_slot = dst_path->slots[cur_level + 1];
2375 child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2376
2377 /* This node is old, no need to trace */
2378 if (child_gen < last_snapshot)
2379 goto out;
2380
2381 eb = btrfs_read_node_slot(eb, parent_slot);
2382 if (IS_ERR(eb)) {
2383 ret = PTR_ERR(eb);
2384 goto out;
2385 }
2386
2387 dst_path->nodes[cur_level] = eb;
2388 dst_path->slots[cur_level] = 0;
2389
2390 btrfs_tree_read_lock(eb);
2391 dst_path->locks[cur_level] = BTRFS_READ_LOCK;
2392 need_cleanup = true;
2393 }
2394
2395 /* Now record this tree block and its counter part for qgroups */
2396 ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
2397 root_level, trace_leaf);
2398 if (ret < 0)
2399 goto cleanup;
2400
2401 eb = dst_path->nodes[cur_level];
2402
2403 if (cur_level > 0) {
2404 /* Iterate all child tree blocks */
2405 for (i = 0; i < btrfs_header_nritems(eb); i++) {
2406 /* Skip old tree blocks as they won't be swapped */
2407 if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2408 continue;
2409 dst_path->slots[cur_level] = i;
2410
2411 /* Recursive call (at most 7 times) */
2412 ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2413 dst_path, cur_level - 1, root_level,
2414 last_snapshot, trace_leaf);
2415 if (ret < 0)
2416 goto cleanup;
2417 }
2418 }
2419
2420cleanup:
2421 if (need_cleanup) {
2422 /* Clean up */
2423 btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2424 dst_path->locks[cur_level]);
2425 free_extent_buffer(dst_path->nodes[cur_level]);
2426 dst_path->nodes[cur_level] = NULL;
2427 dst_path->slots[cur_level] = 0;
2428 dst_path->locks[cur_level] = 0;
2429 }
2430out:
2431 return ret;
2432}
2433
2434static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2435 struct extent_buffer *src_eb,
2436 struct extent_buffer *dst_eb,
2437 u64 last_snapshot, bool trace_leaf)
2438{
2439 struct btrfs_fs_info *fs_info = trans->fs_info;
2440 struct btrfs_path *dst_path = NULL;
2441 int level;
2442 int ret;
2443
2444 if (!btrfs_qgroup_full_accounting(fs_info))
2445 return 0;
2446
2447 /* Wrong parameter order */
2448 if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2449 btrfs_err_rl(fs_info,
2450 "%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2451 btrfs_header_generation(src_eb),
2452 btrfs_header_generation(dst_eb));
2453 return -EUCLEAN;
2454 }
2455
2456 if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2457 ret = -EIO;
2458 goto out;
2459 }
2460
2461 level = btrfs_header_level(dst_eb);
2462 dst_path = btrfs_alloc_path();
2463 if (!dst_path) {
2464 ret = -ENOMEM;
2465 goto out;
2466 }
2467 /* For dst_path */
2468 atomic_inc(&dst_eb->refs);
2469 dst_path->nodes[level] = dst_eb;
2470 dst_path->slots[level] = 0;
2471 dst_path->locks[level] = 0;
2472
2473 /* Do the generation aware breadth-first search */
2474 ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2475 level, last_snapshot, trace_leaf);
2476 if (ret < 0)
2477 goto out;
2478 ret = 0;
2479
2480out:
2481 btrfs_free_path(dst_path);
2482 if (ret < 0)
2483 qgroup_mark_inconsistent(fs_info);
2484 return ret;
2485}
2486
2487/*
2488 * Inform qgroup to trace a whole subtree, including all its child tree
2489 * blocks and data.
2490 * The root tree block is specified by @root_eb.
2491 *
2492 * Normally used by relocation(tree block swap) and subvolume deletion.
2493 *
2494 * Return 0 for success
2495 * Return <0 for error(ENOMEM or tree search error)
2496 */
2497int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2498 struct extent_buffer *root_eb,
2499 u64 root_gen, int root_level)
2500{
2501 struct btrfs_fs_info *fs_info = trans->fs_info;
2502 int ret = 0;
2503 int level;
2504 u8 drop_subptree_thres;
2505 struct extent_buffer *eb = root_eb;
2506 struct btrfs_path *path = NULL;
2507
2508 BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
2509 BUG_ON(root_eb == NULL);
2510
2511 if (!btrfs_qgroup_full_accounting(fs_info))
2512 return 0;
2513
2514 spin_lock(&fs_info->qgroup_lock);
2515 drop_subptree_thres = fs_info->qgroup_drop_subtree_thres;
2516 spin_unlock(&fs_info->qgroup_lock);
2517
2518 /*
2519 * This function only gets called for snapshot drop, if we hit a high
2520 * node here, it means we are going to change ownership for quite a lot
2521 * of extents, which will greatly slow down btrfs_commit_transaction().
2522 *
2523 * So here if we find a high tree here, we just skip the accounting and
2524 * mark qgroup inconsistent.
2525 */
2526 if (root_level >= drop_subptree_thres) {
2527 qgroup_mark_inconsistent(fs_info);
2528 return 0;
2529 }
2530
2531 if (!extent_buffer_uptodate(root_eb)) {
2532 struct btrfs_tree_parent_check check = {
2533 .has_first_key = false,
2534 .transid = root_gen,
2535 .level = root_level
2536 };
2537
2538 ret = btrfs_read_extent_buffer(root_eb, &check);
2539 if (ret)
2540 goto out;
2541 }
2542
2543 if (root_level == 0) {
2544 ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2545 goto out;
2546 }
2547
2548 path = btrfs_alloc_path();
2549 if (!path)
2550 return -ENOMEM;
2551
2552 /*
2553 * Walk down the tree. Missing extent blocks are filled in as
2554 * we go. Metadata is accounted every time we read a new
2555 * extent block.
2556 *
2557 * When we reach a leaf, we account for file extent items in it,
2558 * walk back up the tree (adjusting slot pointers as we go)
2559 * and restart the search process.
2560 */
2561 atomic_inc(&root_eb->refs); /* For path */
2562 path->nodes[root_level] = root_eb;
2563 path->slots[root_level] = 0;
2564 path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2565walk_down:
2566 level = root_level;
2567 while (level >= 0) {
2568 if (path->nodes[level] == NULL) {
2569 int parent_slot;
2570 u64 child_bytenr;
2571
2572 /*
2573 * We need to get child blockptr from parent before we
2574 * can read it.
2575 */
2576 eb = path->nodes[level + 1];
2577 parent_slot = path->slots[level + 1];
2578 child_bytenr = btrfs_node_blockptr(eb, parent_slot);
2579
2580 eb = btrfs_read_node_slot(eb, parent_slot);
2581 if (IS_ERR(eb)) {
2582 ret = PTR_ERR(eb);
2583 goto out;
2584 }
2585
2586 path->nodes[level] = eb;
2587 path->slots[level] = 0;
2588
2589 btrfs_tree_read_lock(eb);
2590 path->locks[level] = BTRFS_READ_LOCK;
2591
2592 ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2593 fs_info->nodesize);
2594 if (ret)
2595 goto out;
2596 }
2597
2598 if (level == 0) {
2599 ret = btrfs_qgroup_trace_leaf_items(trans,
2600 path->nodes[level]);
2601 if (ret)
2602 goto out;
2603
2604 /* Nonzero return here means we completed our search */
2605 ret = adjust_slots_upwards(path, root_level);
2606 if (ret)
2607 break;
2608
2609 /* Restart search with new slots */
2610 goto walk_down;
2611 }
2612
2613 level--;
2614 }
2615
2616 ret = 0;
2617out:
2618 btrfs_free_path(path);
2619
2620 return ret;
2621}
2622
2623static void qgroup_iterator_nested_add(struct list_head *head, struct btrfs_qgroup *qgroup)
2624{
2625 if (!list_empty(&qgroup->nested_iterator))
2626 return;
2627
2628 list_add_tail(&qgroup->nested_iterator, head);
2629}
2630
2631static void qgroup_iterator_nested_clean(struct list_head *head)
2632{
2633 while (!list_empty(head)) {
2634 struct btrfs_qgroup *qgroup;
2635
2636 qgroup = list_first_entry(head, struct btrfs_qgroup, nested_iterator);
2637 list_del_init(&qgroup->nested_iterator);
2638 }
2639}
2640
2641#define UPDATE_NEW 0
2642#define UPDATE_OLD 1
2643/*
2644 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2645 */
2646static void qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2647 struct ulist *roots, struct list_head *qgroups,
2648 u64 seq, int update_old)
2649{
2650 struct ulist_node *unode;
2651 struct ulist_iterator uiter;
2652 struct btrfs_qgroup *qg;
2653
2654 if (!roots)
2655 return;
2656 ULIST_ITER_INIT(&uiter);
2657 while ((unode = ulist_next(roots, &uiter))) {
2658 LIST_HEAD(tmp);
2659
2660 qg = find_qgroup_rb(fs_info, unode->val);
2661 if (!qg)
2662 continue;
2663
2664 qgroup_iterator_nested_add(qgroups, qg);
2665 qgroup_iterator_add(&tmp, qg);
2666 list_for_each_entry(qg, &tmp, iterator) {
2667 struct btrfs_qgroup_list *glist;
2668
2669 if (update_old)
2670 btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2671 else
2672 btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2673
2674 list_for_each_entry(glist, &qg->groups, next_group) {
2675 qgroup_iterator_nested_add(qgroups, glist->group);
2676 qgroup_iterator_add(&tmp, glist->group);
2677 }
2678 }
2679 qgroup_iterator_clean(&tmp);
2680 }
2681}
2682
2683/*
2684 * Update qgroup rfer/excl counters.
2685 * Rfer update is easy, codes can explain themselves.
2686 *
2687 * Excl update is tricky, the update is split into 2 parts.
2688 * Part 1: Possible exclusive <-> sharing detect:
2689 * | A | !A |
2690 * -------------------------------------
2691 * B | * | - |
2692 * -------------------------------------
2693 * !B | + | ** |
2694 * -------------------------------------
2695 *
2696 * Conditions:
2697 * A: cur_old_roots < nr_old_roots (not exclusive before)
2698 * !A: cur_old_roots == nr_old_roots (possible exclusive before)
2699 * B: cur_new_roots < nr_new_roots (not exclusive now)
2700 * !B: cur_new_roots == nr_new_roots (possible exclusive now)
2701 *
2702 * Results:
2703 * +: Possible sharing -> exclusive -: Possible exclusive -> sharing
2704 * *: Definitely not changed. **: Possible unchanged.
2705 *
2706 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2707 *
2708 * To make the logic clear, we first use condition A and B to split
2709 * combination into 4 results.
2710 *
2711 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2712 * only on variant maybe 0.
2713 *
2714 * Lastly, check result **, since there are 2 variants maybe 0, split them
2715 * again(2x2).
2716 * But this time we don't need to consider other things, the codes and logic
2717 * is easy to understand now.
2718 */
2719static void qgroup_update_counters(struct btrfs_fs_info *fs_info,
2720 struct list_head *qgroups, u64 nr_old_roots,
2721 u64 nr_new_roots, u64 num_bytes, u64 seq)
2722{
2723 struct btrfs_qgroup *qg;
2724
2725 list_for_each_entry(qg, qgroups, nested_iterator) {
2726 u64 cur_new_count, cur_old_count;
2727 bool dirty = false;
2728
2729 cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2730 cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2731
2732 trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2733 cur_new_count);
2734
2735 /* Rfer update part */
2736 if (cur_old_count == 0 && cur_new_count > 0) {
2737 qg->rfer += num_bytes;
2738 qg->rfer_cmpr += num_bytes;
2739 dirty = true;
2740 }
2741 if (cur_old_count > 0 && cur_new_count == 0) {
2742 qg->rfer -= num_bytes;
2743 qg->rfer_cmpr -= num_bytes;
2744 dirty = true;
2745 }
2746
2747 /* Excl update part */
2748 /* Exclusive/none -> shared case */
2749 if (cur_old_count == nr_old_roots &&
2750 cur_new_count < nr_new_roots) {
2751 /* Exclusive -> shared */
2752 if (cur_old_count != 0) {
2753 qg->excl -= num_bytes;
2754 qg->excl_cmpr -= num_bytes;
2755 dirty = true;
2756 }
2757 }
2758
2759 /* Shared -> exclusive/none case */
2760 if (cur_old_count < nr_old_roots &&
2761 cur_new_count == nr_new_roots) {
2762 /* Shared->exclusive */
2763 if (cur_new_count != 0) {
2764 qg->excl += num_bytes;
2765 qg->excl_cmpr += num_bytes;
2766 dirty = true;
2767 }
2768 }
2769
2770 /* Exclusive/none -> exclusive/none case */
2771 if (cur_old_count == nr_old_roots &&
2772 cur_new_count == nr_new_roots) {
2773 if (cur_old_count == 0) {
2774 /* None -> exclusive/none */
2775
2776 if (cur_new_count != 0) {
2777 /* None -> exclusive */
2778 qg->excl += num_bytes;
2779 qg->excl_cmpr += num_bytes;
2780 dirty = true;
2781 }
2782 /* None -> none, nothing changed */
2783 } else {
2784 /* Exclusive -> exclusive/none */
2785
2786 if (cur_new_count == 0) {
2787 /* Exclusive -> none */
2788 qg->excl -= num_bytes;
2789 qg->excl_cmpr -= num_bytes;
2790 dirty = true;
2791 }
2792 /* Exclusive -> exclusive, nothing changed */
2793 }
2794 }
2795
2796 if (dirty)
2797 qgroup_dirty(fs_info, qg);
2798 }
2799}
2800
2801/*
2802 * Check if the @roots potentially is a list of fs tree roots
2803 *
2804 * Return 0 for definitely not a fs/subvol tree roots ulist
2805 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2806 * one as well)
2807 */
2808static int maybe_fs_roots(struct ulist *roots)
2809{
2810 struct ulist_node *unode;
2811 struct ulist_iterator uiter;
2812
2813 /* Empty one, still possible for fs roots */
2814 if (!roots || roots->nnodes == 0)
2815 return 1;
2816
2817 ULIST_ITER_INIT(&uiter);
2818 unode = ulist_next(roots, &uiter);
2819 if (!unode)
2820 return 1;
2821
2822 /*
2823 * If it contains fs tree roots, then it must belong to fs/subvol
2824 * trees.
2825 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2826 */
2827 return is_fstree(unode->val);
2828}
2829
2830int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2831 u64 num_bytes, struct ulist *old_roots,
2832 struct ulist *new_roots)
2833{
2834 struct btrfs_fs_info *fs_info = trans->fs_info;
2835 LIST_HEAD(qgroups);
2836 u64 seq;
2837 u64 nr_new_roots = 0;
2838 u64 nr_old_roots = 0;
2839 int ret = 0;
2840
2841 /*
2842 * If quotas get disabled meanwhile, the resources need to be freed and
2843 * we can't just exit here.
2844 */
2845 if (!btrfs_qgroup_full_accounting(fs_info) ||
2846 fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
2847 goto out_free;
2848
2849 if (new_roots) {
2850 if (!maybe_fs_roots(new_roots))
2851 goto out_free;
2852 nr_new_roots = new_roots->nnodes;
2853 }
2854 if (old_roots) {
2855 if (!maybe_fs_roots(old_roots))
2856 goto out_free;
2857 nr_old_roots = old_roots->nnodes;
2858 }
2859
2860 /* Quick exit, either not fs tree roots, or won't affect any qgroup */
2861 if (nr_old_roots == 0 && nr_new_roots == 0)
2862 goto out_free;
2863
2864 BUG_ON(!fs_info->quota_root);
2865
2866 trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2867 num_bytes, nr_old_roots, nr_new_roots);
2868
2869 mutex_lock(&fs_info->qgroup_rescan_lock);
2870 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2871 if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2872 mutex_unlock(&fs_info->qgroup_rescan_lock);
2873 ret = 0;
2874 goto out_free;
2875 }
2876 }
2877 mutex_unlock(&fs_info->qgroup_rescan_lock);
2878
2879 spin_lock(&fs_info->qgroup_lock);
2880 seq = fs_info->qgroup_seq;
2881
2882 /* Update old refcnts using old_roots */
2883 qgroup_update_refcnt(fs_info, old_roots, &qgroups, seq, UPDATE_OLD);
2884
2885 /* Update new refcnts using new_roots */
2886 qgroup_update_refcnt(fs_info, new_roots, &qgroups, seq, UPDATE_NEW);
2887
2888 qgroup_update_counters(fs_info, &qgroups, nr_old_roots, nr_new_roots,
2889 num_bytes, seq);
2890
2891 /*
2892 * We're done using the iterator, release all its qgroups while holding
2893 * fs_info->qgroup_lock so that we don't race with btrfs_remove_qgroup()
2894 * and trigger use-after-free accesses to qgroups.
2895 */
2896 qgroup_iterator_nested_clean(&qgroups);
2897
2898 /*
2899 * Bump qgroup_seq to avoid seq overlap
2900 */
2901 fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2902 spin_unlock(&fs_info->qgroup_lock);
2903out_free:
2904 ulist_free(old_roots);
2905 ulist_free(new_roots);
2906 return ret;
2907}
2908
2909int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2910{
2911 struct btrfs_fs_info *fs_info = trans->fs_info;
2912 struct btrfs_qgroup_extent_record *record;
2913 struct btrfs_delayed_ref_root *delayed_refs;
2914 struct ulist *new_roots = NULL;
2915 struct rb_node *node;
2916 u64 num_dirty_extents = 0;
2917 u64 qgroup_to_skip;
2918 int ret = 0;
2919
2920 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
2921 return 0;
2922
2923 delayed_refs = &trans->transaction->delayed_refs;
2924 qgroup_to_skip = delayed_refs->qgroup_to_skip;
2925 while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2926 record = rb_entry(node, struct btrfs_qgroup_extent_record,
2927 node);
2928
2929 num_dirty_extents++;
2930 trace_btrfs_qgroup_account_extents(fs_info, record);
2931
2932 if (!ret && !(fs_info->qgroup_flags &
2933 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) {
2934 struct btrfs_backref_walk_ctx ctx = { 0 };
2935
2936 ctx.bytenr = record->bytenr;
2937 ctx.fs_info = fs_info;
2938
2939 /*
2940 * Old roots should be searched when inserting qgroup
2941 * extent record.
2942 *
2943 * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case,
2944 * we may have some record inserted during
2945 * NO_ACCOUNTING (thus no old_roots populated), but
2946 * later we start rescan, which clears NO_ACCOUNTING,
2947 * leaving some inserted records without old_roots
2948 * populated.
2949 *
2950 * Those cases are rare and should not cause too much
2951 * time spent during commit_transaction().
2952 */
2953 if (!record->old_roots) {
2954 /* Search commit root to find old_roots */
2955 ret = btrfs_find_all_roots(&ctx, false);
2956 if (ret < 0)
2957 goto cleanup;
2958 record->old_roots = ctx.roots;
2959 ctx.roots = NULL;
2960 }
2961
2962 /* Free the reserved data space */
2963 btrfs_qgroup_free_refroot(fs_info,
2964 record->data_rsv_refroot,
2965 record->data_rsv,
2966 BTRFS_QGROUP_RSV_DATA);
2967 /*
2968 * Use BTRFS_SEQ_LAST as time_seq to do special search,
2969 * which doesn't lock tree or delayed_refs and search
2970 * current root. It's safe inside commit_transaction().
2971 */
2972 ctx.trans = trans;
2973 ctx.time_seq = BTRFS_SEQ_LAST;
2974 ret = btrfs_find_all_roots(&ctx, false);
2975 if (ret < 0)
2976 goto cleanup;
2977 new_roots = ctx.roots;
2978 if (qgroup_to_skip) {
2979 ulist_del(new_roots, qgroup_to_skip, 0);
2980 ulist_del(record->old_roots, qgroup_to_skip,
2981 0);
2982 }
2983 ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2984 record->num_bytes,
2985 record->old_roots,
2986 new_roots);
2987 record->old_roots = NULL;
2988 new_roots = NULL;
2989 }
2990cleanup:
2991 ulist_free(record->old_roots);
2992 ulist_free(new_roots);
2993 new_roots = NULL;
2994 rb_erase(node, &delayed_refs->dirty_extent_root);
2995 kfree(record);
2996
2997 }
2998 trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2999 num_dirty_extents);
3000 return ret;
3001}
3002
3003/*
3004 * Writes all changed qgroups to disk.
3005 * Called by the transaction commit path and the qgroup assign ioctl.
3006 */
3007int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
3008{
3009 struct btrfs_fs_info *fs_info = trans->fs_info;
3010 int ret = 0;
3011
3012 /*
3013 * In case we are called from the qgroup assign ioctl, assert that we
3014 * are holding the qgroup_ioctl_lock, otherwise we can race with a quota
3015 * disable operation (ioctl) and access a freed quota root.
3016 */
3017 if (trans->transaction->state != TRANS_STATE_COMMIT_DOING)
3018 lockdep_assert_held(&fs_info->qgroup_ioctl_lock);
3019
3020 if (!fs_info->quota_root)
3021 return ret;
3022
3023 spin_lock(&fs_info->qgroup_lock);
3024 while (!list_empty(&fs_info->dirty_qgroups)) {
3025 struct btrfs_qgroup *qgroup;
3026 qgroup = list_first_entry(&fs_info->dirty_qgroups,
3027 struct btrfs_qgroup, dirty);
3028 list_del_init(&qgroup->dirty);
3029 spin_unlock(&fs_info->qgroup_lock);
3030 ret = update_qgroup_info_item(trans, qgroup);
3031 if (ret)
3032 qgroup_mark_inconsistent(fs_info);
3033 ret = update_qgroup_limit_item(trans, qgroup);
3034 if (ret)
3035 qgroup_mark_inconsistent(fs_info);
3036 spin_lock(&fs_info->qgroup_lock);
3037 }
3038 if (btrfs_qgroup_enabled(fs_info))
3039 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
3040 else
3041 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
3042 spin_unlock(&fs_info->qgroup_lock);
3043
3044 ret = update_qgroup_status_item(trans);
3045 if (ret)
3046 qgroup_mark_inconsistent(fs_info);
3047
3048 return ret;
3049}
3050
3051static int qgroup_auto_inherit(struct btrfs_fs_info *fs_info,
3052 u64 inode_rootid,
3053 struct btrfs_qgroup_inherit **inherit)
3054{
3055 int i = 0;
3056 u64 num_qgroups = 0;
3057 struct btrfs_qgroup *inode_qg;
3058 struct btrfs_qgroup_list *qg_list;
3059 struct btrfs_qgroup_inherit *res;
3060 size_t struct_sz;
3061 u64 *qgids;
3062
3063 if (*inherit)
3064 return -EEXIST;
3065
3066 inode_qg = find_qgroup_rb(fs_info, inode_rootid);
3067 if (!inode_qg)
3068 return -ENOENT;
3069
3070 num_qgroups = list_count_nodes(&inode_qg->groups);
3071
3072 if (!num_qgroups)
3073 return 0;
3074
3075 struct_sz = struct_size(res, qgroups, num_qgroups);
3076 if (struct_sz == SIZE_MAX)
3077 return -ERANGE;
3078
3079 res = kzalloc(struct_sz, GFP_NOFS);
3080 if (!res)
3081 return -ENOMEM;
3082 res->num_qgroups = num_qgroups;
3083 qgids = res->qgroups;
3084
3085 list_for_each_entry(qg_list, &inode_qg->groups, next_group)
3086 qgids[i] = qg_list->group->qgroupid;
3087
3088 *inherit = res;
3089 return 0;
3090}
3091
3092/*
3093 * Copy the accounting information between qgroups. This is necessary
3094 * when a snapshot or a subvolume is created. Throwing an error will
3095 * cause a transaction abort so we take extra care here to only error
3096 * when a readonly fs is a reasonable outcome.
3097 */
3098int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
3099 u64 objectid, u64 inode_rootid,
3100 struct btrfs_qgroup_inherit *inherit)
3101{
3102 int ret = 0;
3103 int i;
3104 u64 *i_qgroups;
3105 bool committing = false;
3106 struct btrfs_fs_info *fs_info = trans->fs_info;
3107 struct btrfs_root *quota_root;
3108 struct btrfs_qgroup *srcgroup;
3109 struct btrfs_qgroup *dstgroup;
3110 struct btrfs_qgroup *prealloc;
3111 struct btrfs_qgroup_list **qlist_prealloc = NULL;
3112 bool free_inherit = false;
3113 bool need_rescan = false;
3114 u32 level_size = 0;
3115 u64 nums;
3116
3117 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
3118 if (!prealloc)
3119 return -ENOMEM;
3120
3121 /*
3122 * There are only two callers of this function.
3123 *
3124 * One in create_subvol() in the ioctl context, which needs to hold
3125 * the qgroup_ioctl_lock.
3126 *
3127 * The other one in create_pending_snapshot() where no other qgroup
3128 * code can modify the fs as they all need to either start a new trans
3129 * or hold a trans handler, thus we don't need to hold
3130 * qgroup_ioctl_lock.
3131 * This would avoid long and complex lock chain and make lockdep happy.
3132 */
3133 spin_lock(&fs_info->trans_lock);
3134 if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
3135 committing = true;
3136 spin_unlock(&fs_info->trans_lock);
3137
3138 if (!committing)
3139 mutex_lock(&fs_info->qgroup_ioctl_lock);
3140 if (!btrfs_qgroup_enabled(fs_info))
3141 goto out;
3142
3143 quota_root = fs_info->quota_root;
3144 if (!quota_root) {
3145 ret = -EINVAL;
3146 goto out;
3147 }
3148
3149 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && !inherit) {
3150 ret = qgroup_auto_inherit(fs_info, inode_rootid, &inherit);
3151 if (ret)
3152 goto out;
3153 free_inherit = true;
3154 }
3155
3156 if (inherit) {
3157 i_qgroups = (u64 *)(inherit + 1);
3158 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
3159 2 * inherit->num_excl_copies;
3160 for (i = 0; i < nums; ++i) {
3161 srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
3162
3163 /*
3164 * Zero out invalid groups so we can ignore
3165 * them later.
3166 */
3167 if (!srcgroup ||
3168 ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
3169 *i_qgroups = 0ULL;
3170
3171 ++i_qgroups;
3172 }
3173 }
3174
3175 /*
3176 * create a tracking group for the subvol itself
3177 */
3178 ret = add_qgroup_item(trans, quota_root, objectid);
3179 if (ret)
3180 goto out;
3181
3182 /*
3183 * add qgroup to all inherited groups
3184 */
3185 if (inherit) {
3186 i_qgroups = (u64 *)(inherit + 1);
3187 for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
3188 if (*i_qgroups == 0)
3189 continue;
3190 ret = add_qgroup_relation_item(trans, objectid,
3191 *i_qgroups);
3192 if (ret && ret != -EEXIST)
3193 goto out;
3194 ret = add_qgroup_relation_item(trans, *i_qgroups,
3195 objectid);
3196 if (ret && ret != -EEXIST)
3197 goto out;
3198 }
3199 ret = 0;
3200
3201 qlist_prealloc = kcalloc(inherit->num_qgroups,
3202 sizeof(struct btrfs_qgroup_list *),
3203 GFP_NOFS);
3204 if (!qlist_prealloc) {
3205 ret = -ENOMEM;
3206 goto out;
3207 }
3208 for (int i = 0; i < inherit->num_qgroups; i++) {
3209 qlist_prealloc[i] = kzalloc(sizeof(struct btrfs_qgroup_list),
3210 GFP_NOFS);
3211 if (!qlist_prealloc[i]) {
3212 ret = -ENOMEM;
3213 goto out;
3214 }
3215 }
3216 }
3217
3218 spin_lock(&fs_info->qgroup_lock);
3219
3220 dstgroup = add_qgroup_rb(fs_info, prealloc, objectid);
3221 prealloc = NULL;
3222
3223 if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
3224 dstgroup->lim_flags = inherit->lim.flags;
3225 dstgroup->max_rfer = inherit->lim.max_rfer;
3226 dstgroup->max_excl = inherit->lim.max_excl;
3227 dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
3228 dstgroup->rsv_excl = inherit->lim.rsv_excl;
3229
3230 qgroup_dirty(fs_info, dstgroup);
3231 }
3232
3233 if (srcid && btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL) {
3234 srcgroup = find_qgroup_rb(fs_info, srcid);
3235 if (!srcgroup)
3236 goto unlock;
3237
3238 /*
3239 * We call inherit after we clone the root in order to make sure
3240 * our counts don't go crazy, so at this point the only
3241 * difference between the two roots should be the root node.
3242 */
3243 level_size = fs_info->nodesize;
3244 dstgroup->rfer = srcgroup->rfer;
3245 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
3246 dstgroup->excl = level_size;
3247 dstgroup->excl_cmpr = level_size;
3248 srcgroup->excl = level_size;
3249 srcgroup->excl_cmpr = level_size;
3250
3251 /* inherit the limit info */
3252 dstgroup->lim_flags = srcgroup->lim_flags;
3253 dstgroup->max_rfer = srcgroup->max_rfer;
3254 dstgroup->max_excl = srcgroup->max_excl;
3255 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
3256 dstgroup->rsv_excl = srcgroup->rsv_excl;
3257
3258 qgroup_dirty(fs_info, dstgroup);
3259 qgroup_dirty(fs_info, srcgroup);
3260 }
3261
3262 if (!inherit)
3263 goto unlock;
3264
3265 i_qgroups = (u64 *)(inherit + 1);
3266 for (i = 0; i < inherit->num_qgroups; ++i) {
3267 if (*i_qgroups) {
3268 ret = add_relation_rb(fs_info, qlist_prealloc[i], objectid,
3269 *i_qgroups);
3270 qlist_prealloc[i] = NULL;
3271 if (ret)
3272 goto unlock;
3273 }
3274 ++i_qgroups;
3275
3276 /*
3277 * If we're doing a snapshot, and adding the snapshot to a new
3278 * qgroup, the numbers are guaranteed to be incorrect.
3279 */
3280 if (srcid)
3281 need_rescan = true;
3282 }
3283
3284 for (i = 0; i < inherit->num_ref_copies; ++i, i_qgroups += 2) {
3285 struct btrfs_qgroup *src;
3286 struct btrfs_qgroup *dst;
3287
3288 if (!i_qgroups[0] || !i_qgroups[1])
3289 continue;
3290
3291 src = find_qgroup_rb(fs_info, i_qgroups[0]);
3292 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3293
3294 if (!src || !dst) {
3295 ret = -EINVAL;
3296 goto unlock;
3297 }
3298
3299 dst->rfer = src->rfer - level_size;
3300 dst->rfer_cmpr = src->rfer_cmpr - level_size;
3301
3302 /* Manually tweaking numbers certainly needs a rescan */
3303 need_rescan = true;
3304 }
3305 for (i = 0; i < inherit->num_excl_copies; ++i, i_qgroups += 2) {
3306 struct btrfs_qgroup *src;
3307 struct btrfs_qgroup *dst;
3308
3309 if (!i_qgroups[0] || !i_qgroups[1])
3310 continue;
3311
3312 src = find_qgroup_rb(fs_info, i_qgroups[0]);
3313 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3314
3315 if (!src || !dst) {
3316 ret = -EINVAL;
3317 goto unlock;
3318 }
3319
3320 dst->excl = src->excl + level_size;
3321 dst->excl_cmpr = src->excl_cmpr + level_size;
3322 need_rescan = true;
3323 }
3324
3325unlock:
3326 spin_unlock(&fs_info->qgroup_lock);
3327 if (!ret)
3328 ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup);
3329out:
3330 if (!committing)
3331 mutex_unlock(&fs_info->qgroup_ioctl_lock);
3332 if (need_rescan)
3333 qgroup_mark_inconsistent(fs_info);
3334 if (qlist_prealloc) {
3335 for (int i = 0; i < inherit->num_qgroups; i++)
3336 kfree(qlist_prealloc[i]);
3337 kfree(qlist_prealloc);
3338 }
3339 if (free_inherit)
3340 kfree(inherit);
3341 kfree(prealloc);
3342 return ret;
3343}
3344
3345static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes)
3346{
3347 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
3348 qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
3349 return false;
3350
3351 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
3352 qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
3353 return false;
3354
3355 return true;
3356}
3357
3358static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
3359 enum btrfs_qgroup_rsv_type type)
3360{
3361 struct btrfs_qgroup *qgroup;
3362 struct btrfs_fs_info *fs_info = root->fs_info;
3363 u64 ref_root = root->root_key.objectid;
3364 int ret = 0;
3365 LIST_HEAD(qgroup_list);
3366
3367 if (!is_fstree(ref_root))
3368 return 0;
3369
3370 if (num_bytes == 0)
3371 return 0;
3372
3373 if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
3374 capable(CAP_SYS_RESOURCE))
3375 enforce = false;
3376
3377 spin_lock(&fs_info->qgroup_lock);
3378 if (!fs_info->quota_root)
3379 goto out;
3380
3381 qgroup = find_qgroup_rb(fs_info, ref_root);
3382 if (!qgroup)
3383 goto out;
3384
3385 qgroup_iterator_add(&qgroup_list, qgroup);
3386 list_for_each_entry(qgroup, &qgroup_list, iterator) {
3387 struct btrfs_qgroup_list *glist;
3388
3389 if (enforce && !qgroup_check_limits(qgroup, num_bytes)) {
3390 ret = -EDQUOT;
3391 goto out;
3392 }
3393
3394 list_for_each_entry(glist, &qgroup->groups, next_group)
3395 qgroup_iterator_add(&qgroup_list, glist->group);
3396 }
3397
3398 ret = 0;
3399 /*
3400 * no limits exceeded, now record the reservation into all qgroups
3401 */
3402 list_for_each_entry(qgroup, &qgroup_list, iterator)
3403 qgroup_rsv_add(fs_info, qgroup, num_bytes, type);
3404
3405out:
3406 qgroup_iterator_clean(&qgroup_list);
3407 spin_unlock(&fs_info->qgroup_lock);
3408 return ret;
3409}
3410
3411/*
3412 * Free @num_bytes of reserved space with @type for qgroup. (Normally level 0
3413 * qgroup).
3414 *
3415 * Will handle all higher level qgroup too.
3416 *
3417 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
3418 * This special case is only used for META_PERTRANS type.
3419 */
3420void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
3421 u64 ref_root, u64 num_bytes,
3422 enum btrfs_qgroup_rsv_type type)
3423{
3424 struct btrfs_qgroup *qgroup;
3425 LIST_HEAD(qgroup_list);
3426
3427 if (!is_fstree(ref_root))
3428 return;
3429
3430 if (num_bytes == 0)
3431 return;
3432
3433 if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
3434 WARN(1, "%s: Invalid type to free", __func__);
3435 return;
3436 }
3437 spin_lock(&fs_info->qgroup_lock);
3438
3439 if (!fs_info->quota_root)
3440 goto out;
3441
3442 qgroup = find_qgroup_rb(fs_info, ref_root);
3443 if (!qgroup)
3444 goto out;
3445
3446 if (num_bytes == (u64)-1)
3447 /*
3448 * We're freeing all pertrans rsv, get reserved value from
3449 * level 0 qgroup as real num_bytes to free.
3450 */
3451 num_bytes = qgroup->rsv.values[type];
3452
3453 qgroup_iterator_add(&qgroup_list, qgroup);
3454 list_for_each_entry(qgroup, &qgroup_list, iterator) {
3455 struct btrfs_qgroup_list *glist;
3456
3457 qgroup_rsv_release(fs_info, qgroup, num_bytes, type);
3458 list_for_each_entry(glist, &qgroup->groups, next_group) {
3459 qgroup_iterator_add(&qgroup_list, glist->group);
3460 }
3461 }
3462out:
3463 qgroup_iterator_clean(&qgroup_list);
3464 spin_unlock(&fs_info->qgroup_lock);
3465}
3466
3467/*
3468 * Check if the leaf is the last leaf. Which means all node pointers
3469 * are at their last position.
3470 */
3471static bool is_last_leaf(struct btrfs_path *path)
3472{
3473 int i;
3474
3475 for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3476 if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3477 return false;
3478 }
3479 return true;
3480}
3481
3482/*
3483 * returns < 0 on error, 0 when more leafs are to be scanned.
3484 * returns 1 when done.
3485 */
3486static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3487 struct btrfs_path *path)
3488{
3489 struct btrfs_fs_info *fs_info = trans->fs_info;
3490 struct btrfs_root *extent_root;
3491 struct btrfs_key found;
3492 struct extent_buffer *scratch_leaf = NULL;
3493 u64 num_bytes;
3494 bool done;
3495 int slot;
3496 int ret;
3497
3498 if (!btrfs_qgroup_full_accounting(fs_info))
3499 return 1;
3500
3501 mutex_lock(&fs_info->qgroup_rescan_lock);
3502 extent_root = btrfs_extent_root(fs_info,
3503 fs_info->qgroup_rescan_progress.objectid);
3504 ret = btrfs_search_slot_for_read(extent_root,
3505 &fs_info->qgroup_rescan_progress,
3506 path, 1, 0);
3507
3508 btrfs_debug(fs_info,
3509 "current progress key (%llu %u %llu), search_slot ret %d",
3510 fs_info->qgroup_rescan_progress.objectid,
3511 fs_info->qgroup_rescan_progress.type,
3512 fs_info->qgroup_rescan_progress.offset, ret);
3513
3514 if (ret) {
3515 /*
3516 * The rescan is about to end, we will not be scanning any
3517 * further blocks. We cannot unset the RESCAN flag here, because
3518 * we want to commit the transaction if everything went well.
3519 * To make the live accounting work in this phase, we set our
3520 * scan progress pointer such that every real extent objectid
3521 * will be smaller.
3522 */
3523 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3524 btrfs_release_path(path);
3525 mutex_unlock(&fs_info->qgroup_rescan_lock);
3526 return ret;
3527 }
3528 done = is_last_leaf(path);
3529
3530 btrfs_item_key_to_cpu(path->nodes[0], &found,
3531 btrfs_header_nritems(path->nodes[0]) - 1);
3532 fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3533
3534 scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3535 if (!scratch_leaf) {
3536 ret = -ENOMEM;
3537 mutex_unlock(&fs_info->qgroup_rescan_lock);
3538 goto out;
3539 }
3540 slot = path->slots[0];
3541 btrfs_release_path(path);
3542 mutex_unlock(&fs_info->qgroup_rescan_lock);
3543
3544 for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3545 struct btrfs_backref_walk_ctx ctx = { 0 };
3546
3547 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3548 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3549 found.type != BTRFS_METADATA_ITEM_KEY)
3550 continue;
3551 if (found.type == BTRFS_METADATA_ITEM_KEY)
3552 num_bytes = fs_info->nodesize;
3553 else
3554 num_bytes = found.offset;
3555
3556 ctx.bytenr = found.objectid;
3557 ctx.fs_info = fs_info;
3558
3559 ret = btrfs_find_all_roots(&ctx, false);
3560 if (ret < 0)
3561 goto out;
3562 /* For rescan, just pass old_roots as NULL */
3563 ret = btrfs_qgroup_account_extent(trans, found.objectid,
3564 num_bytes, NULL, ctx.roots);
3565 if (ret < 0)
3566 goto out;
3567 }
3568out:
3569 if (scratch_leaf)
3570 free_extent_buffer(scratch_leaf);
3571
3572 if (done && !ret) {
3573 ret = 1;
3574 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3575 }
3576 return ret;
3577}
3578
3579static bool rescan_should_stop(struct btrfs_fs_info *fs_info)
3580{
3581 if (btrfs_fs_closing(fs_info))
3582 return true;
3583 if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
3584 return true;
3585 if (!btrfs_qgroup_enabled(fs_info))
3586 return true;
3587 if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3588 return true;
3589 return false;
3590}
3591
3592static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3593{
3594 struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3595 qgroup_rescan_work);
3596 struct btrfs_path *path;
3597 struct btrfs_trans_handle *trans = NULL;
3598 int err = -ENOMEM;
3599 int ret = 0;
3600 bool stopped = false;
3601 bool did_leaf_rescans = false;
3602
3603 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
3604 return;
3605
3606 path = btrfs_alloc_path();
3607 if (!path)
3608 goto out;
3609 /*
3610 * Rescan should only search for commit root, and any later difference
3611 * should be recorded by qgroup
3612 */
3613 path->search_commit_root = 1;
3614 path->skip_locking = 1;
3615
3616 err = 0;
3617 while (!err && !(stopped = rescan_should_stop(fs_info))) {
3618 trans = btrfs_start_transaction(fs_info->fs_root, 0);
3619 if (IS_ERR(trans)) {
3620 err = PTR_ERR(trans);
3621 break;
3622 }
3623
3624 err = qgroup_rescan_leaf(trans, path);
3625 did_leaf_rescans = true;
3626
3627 if (err > 0)
3628 btrfs_commit_transaction(trans);
3629 else
3630 btrfs_end_transaction(trans);
3631 }
3632
3633out:
3634 btrfs_free_path(path);
3635
3636 mutex_lock(&fs_info->qgroup_rescan_lock);
3637 if (err > 0 &&
3638 fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3639 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3640 } else if (err < 0 || stopped) {
3641 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3642 }
3643 mutex_unlock(&fs_info->qgroup_rescan_lock);
3644
3645 /*
3646 * Only update status, since the previous part has already updated the
3647 * qgroup info, and only if we did any actual work. This also prevents
3648 * race with a concurrent quota disable, which has already set
3649 * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at
3650 * btrfs_quota_disable().
3651 */
3652 if (did_leaf_rescans) {
3653 trans = btrfs_start_transaction(fs_info->quota_root, 1);
3654 if (IS_ERR(trans)) {
3655 err = PTR_ERR(trans);
3656 trans = NULL;
3657 btrfs_err(fs_info,
3658 "fail to start transaction for status update: %d",
3659 err);
3660 }
3661 } else {
3662 trans = NULL;
3663 }
3664
3665 mutex_lock(&fs_info->qgroup_rescan_lock);
3666 if (!stopped ||
3667 fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3668 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3669 if (trans) {
3670 ret = update_qgroup_status_item(trans);
3671 if (ret < 0) {
3672 err = ret;
3673 btrfs_err(fs_info, "fail to update qgroup status: %d",
3674 err);
3675 }
3676 }
3677 fs_info->qgroup_rescan_running = false;
3678 fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3679 complete_all(&fs_info->qgroup_rescan_completion);
3680 mutex_unlock(&fs_info->qgroup_rescan_lock);
3681
3682 if (!trans)
3683 return;
3684
3685 btrfs_end_transaction(trans);
3686
3687 if (stopped) {
3688 btrfs_info(fs_info, "qgroup scan paused");
3689 } else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) {
3690 btrfs_info(fs_info, "qgroup scan cancelled");
3691 } else if (err >= 0) {
3692 btrfs_info(fs_info, "qgroup scan completed%s",
3693 err > 0 ? " (inconsistency flag cleared)" : "");
3694 } else {
3695 btrfs_err(fs_info, "qgroup scan failed with %d", err);
3696 }
3697}
3698
3699/*
3700 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3701 * memory required for the rescan context.
3702 */
3703static int
3704qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3705 int init_flags)
3706{
3707 int ret = 0;
3708
3709 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) {
3710 btrfs_warn(fs_info, "qgroup rescan init failed, running in simple mode");
3711 return -EINVAL;
3712 }
3713
3714 if (!init_flags) {
3715 /* we're resuming qgroup rescan at mount time */
3716 if (!(fs_info->qgroup_flags &
3717 BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3718 btrfs_warn(fs_info,
3719 "qgroup rescan init failed, qgroup rescan is not queued");
3720 ret = -EINVAL;
3721 } else if (!(fs_info->qgroup_flags &
3722 BTRFS_QGROUP_STATUS_FLAG_ON)) {
3723 btrfs_warn(fs_info,
3724 "qgroup rescan init failed, qgroup is not enabled");
3725 ret = -EINVAL;
3726 }
3727
3728 if (ret)
3729 return ret;
3730 }
3731
3732 mutex_lock(&fs_info->qgroup_rescan_lock);
3733
3734 if (init_flags) {
3735 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3736 btrfs_warn(fs_info,
3737 "qgroup rescan is already in progress");
3738 ret = -EINPROGRESS;
3739 } else if (!(fs_info->qgroup_flags &
3740 BTRFS_QGROUP_STATUS_FLAG_ON)) {
3741 btrfs_warn(fs_info,
3742 "qgroup rescan init failed, qgroup is not enabled");
3743 ret = -EINVAL;
3744 } else if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
3745 /* Quota disable is in progress */
3746 ret = -EBUSY;
3747 }
3748
3749 if (ret) {
3750 mutex_unlock(&fs_info->qgroup_rescan_lock);
3751 return ret;
3752 }
3753 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3754 }
3755
3756 memset(&fs_info->qgroup_rescan_progress, 0,
3757 sizeof(fs_info->qgroup_rescan_progress));
3758 fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
3759 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
3760 fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3761 init_completion(&fs_info->qgroup_rescan_completion);
3762 mutex_unlock(&fs_info->qgroup_rescan_lock);
3763
3764 btrfs_init_work(&fs_info->qgroup_rescan_work,
3765 btrfs_qgroup_rescan_worker, NULL);
3766 return 0;
3767}
3768
3769static void
3770qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3771{
3772 struct rb_node *n;
3773 struct btrfs_qgroup *qgroup;
3774
3775 spin_lock(&fs_info->qgroup_lock);
3776 /* clear all current qgroup tracking information */
3777 for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3778 qgroup = rb_entry(n, struct btrfs_qgroup, node);
3779 qgroup->rfer = 0;
3780 qgroup->rfer_cmpr = 0;
3781 qgroup->excl = 0;
3782 qgroup->excl_cmpr = 0;
3783 qgroup_dirty(fs_info, qgroup);
3784 }
3785 spin_unlock(&fs_info->qgroup_lock);
3786}
3787
3788int
3789btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3790{
3791 int ret = 0;
3792 struct btrfs_trans_handle *trans;
3793
3794 ret = qgroup_rescan_init(fs_info, 0, 1);
3795 if (ret)
3796 return ret;
3797
3798 /*
3799 * We have set the rescan_progress to 0, which means no more
3800 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3801 * However, btrfs_qgroup_account_ref may be right after its call
3802 * to btrfs_find_all_roots, in which case it would still do the
3803 * accounting.
3804 * To solve this, we're committing the transaction, which will
3805 * ensure we run all delayed refs and only after that, we are
3806 * going to clear all tracking information for a clean start.
3807 */
3808
3809 trans = btrfs_attach_transaction_barrier(fs_info->fs_root);
3810 if (IS_ERR(trans) && trans != ERR_PTR(-ENOENT)) {
3811 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3812 return PTR_ERR(trans);
3813 } else if (trans != ERR_PTR(-ENOENT)) {
3814 ret = btrfs_commit_transaction(trans);
3815 if (ret) {
3816 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3817 return ret;
3818 }
3819 }
3820
3821 qgroup_rescan_zero_tracking(fs_info);
3822
3823 mutex_lock(&fs_info->qgroup_rescan_lock);
3824 fs_info->qgroup_rescan_running = true;
3825 btrfs_queue_work(fs_info->qgroup_rescan_workers,
3826 &fs_info->qgroup_rescan_work);
3827 mutex_unlock(&fs_info->qgroup_rescan_lock);
3828
3829 return 0;
3830}
3831
3832int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3833 bool interruptible)
3834{
3835 int running;
3836 int ret = 0;
3837
3838 mutex_lock(&fs_info->qgroup_rescan_lock);
3839 running = fs_info->qgroup_rescan_running;
3840 mutex_unlock(&fs_info->qgroup_rescan_lock);
3841
3842 if (!running)
3843 return 0;
3844
3845 if (interruptible)
3846 ret = wait_for_completion_interruptible(
3847 &fs_info->qgroup_rescan_completion);
3848 else
3849 wait_for_completion(&fs_info->qgroup_rescan_completion);
3850
3851 return ret;
3852}
3853
3854/*
3855 * this is only called from open_ctree where we're still single threaded, thus
3856 * locking is omitted here.
3857 */
3858void
3859btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3860{
3861 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3862 mutex_lock(&fs_info->qgroup_rescan_lock);
3863 fs_info->qgroup_rescan_running = true;
3864 btrfs_queue_work(fs_info->qgroup_rescan_workers,
3865 &fs_info->qgroup_rescan_work);
3866 mutex_unlock(&fs_info->qgroup_rescan_lock);
3867 }
3868}
3869
3870#define rbtree_iterate_from_safe(node, next, start) \
3871 for (node = start; node && ({ next = rb_next(node); 1;}); node = next)
3872
3873static int qgroup_unreserve_range(struct btrfs_inode *inode,
3874 struct extent_changeset *reserved, u64 start,
3875 u64 len)
3876{
3877 struct rb_node *node;
3878 struct rb_node *next;
3879 struct ulist_node *entry;
3880 int ret = 0;
3881
3882 node = reserved->range_changed.root.rb_node;
3883 if (!node)
3884 return 0;
3885 while (node) {
3886 entry = rb_entry(node, struct ulist_node, rb_node);
3887 if (entry->val < start)
3888 node = node->rb_right;
3889 else
3890 node = node->rb_left;
3891 }
3892
3893 if (entry->val > start && rb_prev(&entry->rb_node))
3894 entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
3895 rb_node);
3896
3897 rbtree_iterate_from_safe(node, next, &entry->rb_node) {
3898 u64 entry_start;
3899 u64 entry_end;
3900 u64 entry_len;
3901 int clear_ret;
3902
3903 entry = rb_entry(node, struct ulist_node, rb_node);
3904 entry_start = entry->val;
3905 entry_end = entry->aux;
3906 entry_len = entry_end - entry_start + 1;
3907
3908 if (entry_start >= start + len)
3909 break;
3910 if (entry_start + entry_len <= start)
3911 continue;
3912 /*
3913 * Now the entry is in [start, start + len), revert the
3914 * EXTENT_QGROUP_RESERVED bit.
3915 */
3916 clear_ret = clear_extent_bits(&inode->io_tree, entry_start,
3917 entry_end, EXTENT_QGROUP_RESERVED);
3918 if (!ret && clear_ret < 0)
3919 ret = clear_ret;
3920
3921 ulist_del(&reserved->range_changed, entry->val, entry->aux);
3922 if (likely(reserved->bytes_changed >= entry_len)) {
3923 reserved->bytes_changed -= entry_len;
3924 } else {
3925 WARN_ON(1);
3926 reserved->bytes_changed = 0;
3927 }
3928 }
3929
3930 return ret;
3931}
3932
3933/*
3934 * Try to free some space for qgroup.
3935 *
3936 * For qgroup, there are only 3 ways to free qgroup space:
3937 * - Flush nodatacow write
3938 * Any nodatacow write will free its reserved data space at run_delalloc_range().
3939 * In theory, we should only flush nodatacow inodes, but it's not yet
3940 * possible, so we need to flush the whole root.
3941 *
3942 * - Wait for ordered extents
3943 * When ordered extents are finished, their reserved metadata is finally
3944 * converted to per_trans status, which can be freed by later commit
3945 * transaction.
3946 *
3947 * - Commit transaction
3948 * This would free the meta_per_trans space.
3949 * In theory this shouldn't provide much space, but any more qgroup space
3950 * is needed.
3951 */
3952static int try_flush_qgroup(struct btrfs_root *root)
3953{
3954 struct btrfs_trans_handle *trans;
3955 int ret;
3956
3957 /* Can't hold an open transaction or we run the risk of deadlocking. */
3958 ASSERT(current->journal_info == NULL);
3959 if (WARN_ON(current->journal_info))
3960 return 0;
3961
3962 /*
3963 * We don't want to run flush again and again, so if there is a running
3964 * one, we won't try to start a new flush, but exit directly.
3965 */
3966 if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) {
3967 wait_event(root->qgroup_flush_wait,
3968 !test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state));
3969 return 0;
3970 }
3971
3972 ret = btrfs_start_delalloc_snapshot(root, true);
3973 if (ret < 0)
3974 goto out;
3975 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
3976
3977 trans = btrfs_attach_transaction_barrier(root);
3978 if (IS_ERR(trans)) {
3979 ret = PTR_ERR(trans);
3980 if (ret == -ENOENT)
3981 ret = 0;
3982 goto out;
3983 }
3984
3985 ret = btrfs_commit_transaction(trans);
3986out:
3987 clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state);
3988 wake_up(&root->qgroup_flush_wait);
3989 return ret;
3990}
3991
3992static int qgroup_reserve_data(struct btrfs_inode *inode,
3993 struct extent_changeset **reserved_ret, u64 start,
3994 u64 len)
3995{
3996 struct btrfs_root *root = inode->root;
3997 struct extent_changeset *reserved;
3998 bool new_reserved = false;
3999 u64 orig_reserved;
4000 u64 to_reserve;
4001 int ret;
4002
4003 if (btrfs_qgroup_mode(root->fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4004 !is_fstree(root->root_key.objectid) || len == 0)
4005 return 0;
4006
4007 /* @reserved parameter is mandatory for qgroup */
4008 if (WARN_ON(!reserved_ret))
4009 return -EINVAL;
4010 if (!*reserved_ret) {
4011 new_reserved = true;
4012 *reserved_ret = extent_changeset_alloc();
4013 if (!*reserved_ret)
4014 return -ENOMEM;
4015 }
4016 reserved = *reserved_ret;
4017 /* Record already reserved space */
4018 orig_reserved = reserved->bytes_changed;
4019 ret = set_record_extent_bits(&inode->io_tree, start,
4020 start + len -1, EXTENT_QGROUP_RESERVED, reserved);
4021
4022 /* Newly reserved space */
4023 to_reserve = reserved->bytes_changed - orig_reserved;
4024 trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len,
4025 to_reserve, QGROUP_RESERVE);
4026 if (ret < 0)
4027 goto out;
4028 ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
4029 if (ret < 0)
4030 goto cleanup;
4031
4032 return ret;
4033
4034cleanup:
4035 qgroup_unreserve_range(inode, reserved, start, len);
4036out:
4037 if (new_reserved) {
4038 extent_changeset_free(reserved);
4039 *reserved_ret = NULL;
4040 }
4041 return ret;
4042}
4043
4044/*
4045 * Reserve qgroup space for range [start, start + len).
4046 *
4047 * This function will either reserve space from related qgroups or do nothing
4048 * if the range is already reserved.
4049 *
4050 * Return 0 for successful reservation
4051 * Return <0 for error (including -EQUOT)
4052 *
4053 * NOTE: This function may sleep for memory allocation, dirty page flushing and
4054 * commit transaction. So caller should not hold any dirty page locked.
4055 */
4056int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
4057 struct extent_changeset **reserved_ret, u64 start,
4058 u64 len)
4059{
4060 int ret;
4061
4062 ret = qgroup_reserve_data(inode, reserved_ret, start, len);
4063 if (ret <= 0 && ret != -EDQUOT)
4064 return ret;
4065
4066 ret = try_flush_qgroup(inode->root);
4067 if (ret < 0)
4068 return ret;
4069 return qgroup_reserve_data(inode, reserved_ret, start, len);
4070}
4071
4072/* Free ranges specified by @reserved, normally in error path */
4073static int qgroup_free_reserved_data(struct btrfs_inode *inode,
4074 struct extent_changeset *reserved,
4075 u64 start, u64 len, u64 *freed_ret)
4076{
4077 struct btrfs_root *root = inode->root;
4078 struct ulist_node *unode;
4079 struct ulist_iterator uiter;
4080 struct extent_changeset changeset;
4081 u64 freed = 0;
4082 int ret;
4083
4084 extent_changeset_init(&changeset);
4085 len = round_up(start + len, root->fs_info->sectorsize);
4086 start = round_down(start, root->fs_info->sectorsize);
4087
4088 ULIST_ITER_INIT(&uiter);
4089 while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
4090 u64 range_start = unode->val;
4091 /* unode->aux is the inclusive end */
4092 u64 range_len = unode->aux - range_start + 1;
4093 u64 free_start;
4094 u64 free_len;
4095
4096 extent_changeset_release(&changeset);
4097
4098 /* Only free range in range [start, start + len) */
4099 if (range_start >= start + len ||
4100 range_start + range_len <= start)
4101 continue;
4102 free_start = max(range_start, start);
4103 free_len = min(start + len, range_start + range_len) -
4104 free_start;
4105 /*
4106 * TODO: To also modify reserved->ranges_reserved to reflect
4107 * the modification.
4108 *
4109 * However as long as we free qgroup reserved according to
4110 * EXTENT_QGROUP_RESERVED, we won't double free.
4111 * So not need to rush.
4112 */
4113 ret = clear_record_extent_bits(&inode->io_tree, free_start,
4114 free_start + free_len - 1,
4115 EXTENT_QGROUP_RESERVED, &changeset);
4116 if (ret < 0)
4117 goto out;
4118 freed += changeset.bytes_changed;
4119 }
4120 btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
4121 BTRFS_QGROUP_RSV_DATA);
4122 if (freed_ret)
4123 *freed_ret = freed;
4124 ret = 0;
4125out:
4126 extent_changeset_release(&changeset);
4127 return ret;
4128}
4129
4130static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
4131 struct extent_changeset *reserved, u64 start, u64 len,
4132 u64 *released, int free)
4133{
4134 struct extent_changeset changeset;
4135 int trace_op = QGROUP_RELEASE;
4136 int ret;
4137
4138 if (btrfs_qgroup_mode(inode->root->fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
4139 extent_changeset_init(&changeset);
4140 return clear_record_extent_bits(&inode->io_tree, start,
4141 start + len - 1,
4142 EXTENT_QGROUP_RESERVED, &changeset);
4143 }
4144
4145 /* In release case, we shouldn't have @reserved */
4146 WARN_ON(!free && reserved);
4147 if (free && reserved)
4148 return qgroup_free_reserved_data(inode, reserved, start, len, released);
4149 extent_changeset_init(&changeset);
4150 ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
4151 EXTENT_QGROUP_RESERVED, &changeset);
4152 if (ret < 0)
4153 goto out;
4154
4155 if (free)
4156 trace_op = QGROUP_FREE;
4157 trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len,
4158 changeset.bytes_changed, trace_op);
4159 if (free)
4160 btrfs_qgroup_free_refroot(inode->root->fs_info,
4161 inode->root->root_key.objectid,
4162 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4163 if (released)
4164 *released = changeset.bytes_changed;
4165out:
4166 extent_changeset_release(&changeset);
4167 return ret;
4168}
4169
4170/*
4171 * Free a reserved space range from io_tree and related qgroups
4172 *
4173 * Should be called when a range of pages get invalidated before reaching disk.
4174 * Or for error cleanup case.
4175 * if @reserved is given, only reserved range in [@start, @start + @len) will
4176 * be freed.
4177 *
4178 * For data written to disk, use btrfs_qgroup_release_data().
4179 *
4180 * NOTE: This function may sleep for memory allocation.
4181 */
4182int btrfs_qgroup_free_data(struct btrfs_inode *inode,
4183 struct extent_changeset *reserved,
4184 u64 start, u64 len, u64 *freed)
4185{
4186 return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1);
4187}
4188
4189/*
4190 * Release a reserved space range from io_tree only.
4191 *
4192 * Should be called when a range of pages get written to disk and corresponding
4193 * FILE_EXTENT is inserted into corresponding root.
4194 *
4195 * Since new qgroup accounting framework will only update qgroup numbers at
4196 * commit_transaction() time, its reserved space shouldn't be freed from
4197 * related qgroups.
4198 *
4199 * But we should release the range from io_tree, to allow further write to be
4200 * COWed.
4201 *
4202 * NOTE: This function may sleep for memory allocation.
4203 */
4204int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released)
4205{
4206 return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0);
4207}
4208
4209static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4210 enum btrfs_qgroup_rsv_type type)
4211{
4212 if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4213 type != BTRFS_QGROUP_RSV_META_PERTRANS)
4214 return;
4215 if (num_bytes == 0)
4216 return;
4217
4218 spin_lock(&root->qgroup_meta_rsv_lock);
4219 if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
4220 root->qgroup_meta_rsv_prealloc += num_bytes;
4221 else
4222 root->qgroup_meta_rsv_pertrans += num_bytes;
4223 spin_unlock(&root->qgroup_meta_rsv_lock);
4224}
4225
4226static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4227 enum btrfs_qgroup_rsv_type type)
4228{
4229 if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4230 type != BTRFS_QGROUP_RSV_META_PERTRANS)
4231 return 0;
4232 if (num_bytes == 0)
4233 return 0;
4234
4235 spin_lock(&root->qgroup_meta_rsv_lock);
4236 if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
4237 num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
4238 num_bytes);
4239 root->qgroup_meta_rsv_prealloc -= num_bytes;
4240 } else {
4241 num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
4242 num_bytes);
4243 root->qgroup_meta_rsv_pertrans -= num_bytes;
4244 }
4245 spin_unlock(&root->qgroup_meta_rsv_lock);
4246 return num_bytes;
4247}
4248
4249int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4250 enum btrfs_qgroup_rsv_type type, bool enforce)
4251{
4252 struct btrfs_fs_info *fs_info = root->fs_info;
4253 int ret;
4254
4255 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4256 !is_fstree(root->root_key.objectid) || num_bytes == 0)
4257 return 0;
4258
4259 BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4260 trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
4261 ret = qgroup_reserve(root, num_bytes, enforce, type);
4262 if (ret < 0)
4263 return ret;
4264 /*
4265 * Record what we have reserved into root.
4266 *
4267 * To avoid quota disabled->enabled underflow.
4268 * In that case, we may try to free space we haven't reserved
4269 * (since quota was disabled), so record what we reserved into root.
4270 * And ensure later release won't underflow this number.
4271 */
4272 add_root_meta_rsv(root, num_bytes, type);
4273 return ret;
4274}
4275
4276int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4277 enum btrfs_qgroup_rsv_type type, bool enforce,
4278 bool noflush)
4279{
4280 int ret;
4281
4282 ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4283 if ((ret <= 0 && ret != -EDQUOT) || noflush)
4284 return ret;
4285
4286 ret = try_flush_qgroup(root);
4287 if (ret < 0)
4288 return ret;
4289 return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4290}
4291
4292/*
4293 * Per-transaction meta reservation should be all freed at transaction commit
4294 * time
4295 */
4296void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
4297{
4298 struct btrfs_fs_info *fs_info = root->fs_info;
4299
4300 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4301 !is_fstree(root->root_key.objectid))
4302 return;
4303
4304 /* TODO: Update trace point to handle such free */
4305 trace_qgroup_meta_free_all_pertrans(root);
4306 /* Special value -1 means to free all reserved space */
4307 btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
4308 BTRFS_QGROUP_RSV_META_PERTRANS);
4309}
4310
4311void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
4312 enum btrfs_qgroup_rsv_type type)
4313{
4314 struct btrfs_fs_info *fs_info = root->fs_info;
4315
4316 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4317 !is_fstree(root->root_key.objectid))
4318 return;
4319
4320 /*
4321 * reservation for META_PREALLOC can happen before quota is enabled,
4322 * which can lead to underflow.
4323 * Here ensure we will only free what we really have reserved.
4324 */
4325 num_bytes = sub_root_meta_rsv(root, num_bytes, type);
4326 BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4327 trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
4328 btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
4329 num_bytes, type);
4330}
4331
4332static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
4333 int num_bytes)
4334{
4335 struct btrfs_qgroup *qgroup;
4336 LIST_HEAD(qgroup_list);
4337
4338 if (num_bytes == 0)
4339 return;
4340 if (!fs_info->quota_root)
4341 return;
4342
4343 spin_lock(&fs_info->qgroup_lock);
4344 qgroup = find_qgroup_rb(fs_info, ref_root);
4345 if (!qgroup)
4346 goto out;
4347
4348 qgroup_iterator_add(&qgroup_list, qgroup);
4349 list_for_each_entry(qgroup, &qgroup_list, iterator) {
4350 struct btrfs_qgroup_list *glist;
4351
4352 qgroup_rsv_release(fs_info, qgroup, num_bytes,
4353 BTRFS_QGROUP_RSV_META_PREALLOC);
4354 if (!sb_rdonly(fs_info->sb))
4355 qgroup_rsv_add(fs_info, qgroup, num_bytes,
4356 BTRFS_QGROUP_RSV_META_PERTRANS);
4357
4358 list_for_each_entry(glist, &qgroup->groups, next_group)
4359 qgroup_iterator_add(&qgroup_list, glist->group);
4360 }
4361out:
4362 qgroup_iterator_clean(&qgroup_list);
4363 spin_unlock(&fs_info->qgroup_lock);
4364}
4365
4366/*
4367 * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS.
4368 *
4369 * This is called when preallocated meta reservation needs to be used.
4370 * Normally after btrfs_join_transaction() call.
4371 */
4372void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
4373{
4374 struct btrfs_fs_info *fs_info = root->fs_info;
4375
4376 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4377 !is_fstree(root->root_key.objectid))
4378 return;
4379 /* Same as btrfs_qgroup_free_meta_prealloc() */
4380 num_bytes = sub_root_meta_rsv(root, num_bytes,
4381 BTRFS_QGROUP_RSV_META_PREALLOC);
4382 trace_qgroup_meta_convert(root, num_bytes);
4383 qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
4384}
4385
4386/*
4387 * Check qgroup reserved space leaking, normally at destroy inode
4388 * time
4389 */
4390void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode)
4391{
4392 struct extent_changeset changeset;
4393 struct ulist_node *unode;
4394 struct ulist_iterator iter;
4395 int ret;
4396
4397 extent_changeset_init(&changeset);
4398 ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1,
4399 EXTENT_QGROUP_RESERVED, &changeset);
4400
4401 WARN_ON(ret < 0);
4402 if (WARN_ON(changeset.bytes_changed)) {
4403 ULIST_ITER_INIT(&iter);
4404 while ((unode = ulist_next(&changeset.range_changed, &iter))) {
4405 btrfs_warn(inode->root->fs_info,
4406 "leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu",
4407 btrfs_ino(inode), unode->val, unode->aux);
4408 }
4409 btrfs_qgroup_free_refroot(inode->root->fs_info,
4410 inode->root->root_key.objectid,
4411 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4412
4413 }
4414 extent_changeset_release(&changeset);
4415}
4416
4417void btrfs_qgroup_init_swapped_blocks(
4418 struct btrfs_qgroup_swapped_blocks *swapped_blocks)
4419{
4420 int i;
4421
4422 spin_lock_init(&swapped_blocks->lock);
4423 for (i = 0; i < BTRFS_MAX_LEVEL; i++)
4424 swapped_blocks->blocks[i] = RB_ROOT;
4425 swapped_blocks->swapped = false;
4426}
4427
4428/*
4429 * Delete all swapped blocks record of @root.
4430 * Every record here means we skipped a full subtree scan for qgroup.
4431 *
4432 * Gets called when committing one transaction.
4433 */
4434void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
4435{
4436 struct btrfs_qgroup_swapped_blocks *swapped_blocks;
4437 int i;
4438
4439 swapped_blocks = &root->swapped_blocks;
4440
4441 spin_lock(&swapped_blocks->lock);
4442 if (!swapped_blocks->swapped)
4443 goto out;
4444 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4445 struct rb_root *cur_root = &swapped_blocks->blocks[i];
4446 struct btrfs_qgroup_swapped_block *entry;
4447 struct btrfs_qgroup_swapped_block *next;
4448
4449 rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
4450 node)
4451 kfree(entry);
4452 swapped_blocks->blocks[i] = RB_ROOT;
4453 }
4454 swapped_blocks->swapped = false;
4455out:
4456 spin_unlock(&swapped_blocks->lock);
4457}
4458
4459/*
4460 * Add subtree roots record into @subvol_root.
4461 *
4462 * @subvol_root: tree root of the subvolume tree get swapped
4463 * @bg: block group under balance
4464 * @subvol_parent/slot: pointer to the subtree root in subvolume tree
4465 * @reloc_parent/slot: pointer to the subtree root in reloc tree
4466 * BOTH POINTERS ARE BEFORE TREE SWAP
4467 * @last_snapshot: last snapshot generation of the subvolume tree
4468 */
4469int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
4470 struct btrfs_root *subvol_root,
4471 struct btrfs_block_group *bg,
4472 struct extent_buffer *subvol_parent, int subvol_slot,
4473 struct extent_buffer *reloc_parent, int reloc_slot,
4474 u64 last_snapshot)
4475{
4476 struct btrfs_fs_info *fs_info = subvol_root->fs_info;
4477 struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
4478 struct btrfs_qgroup_swapped_block *block;
4479 struct rb_node **cur;
4480 struct rb_node *parent = NULL;
4481 int level = btrfs_header_level(subvol_parent) - 1;
4482 int ret = 0;
4483
4484 if (!btrfs_qgroup_full_accounting(fs_info))
4485 return 0;
4486
4487 if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
4488 btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
4489 btrfs_err_rl(fs_info,
4490 "%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
4491 __func__,
4492 btrfs_node_ptr_generation(subvol_parent, subvol_slot),
4493 btrfs_node_ptr_generation(reloc_parent, reloc_slot));
4494 return -EUCLEAN;
4495 }
4496
4497 block = kmalloc(sizeof(*block), GFP_NOFS);
4498 if (!block) {
4499 ret = -ENOMEM;
4500 goto out;
4501 }
4502
4503 /*
4504 * @reloc_parent/slot is still before swap, while @block is going to
4505 * record the bytenr after swap, so we do the swap here.
4506 */
4507 block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
4508 block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
4509 reloc_slot);
4510 block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
4511 block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
4512 subvol_slot);
4513 block->last_snapshot = last_snapshot;
4514 block->level = level;
4515
4516 /*
4517 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
4518 * no one else can modify tree blocks thus we qgroup will not change
4519 * no matter the value of trace_leaf.
4520 */
4521 if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
4522 block->trace_leaf = true;
4523 else
4524 block->trace_leaf = false;
4525 btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
4526
4527 /* Insert @block into @blocks */
4528 spin_lock(&blocks->lock);
4529 cur = &blocks->blocks[level].rb_node;
4530 while (*cur) {
4531 struct btrfs_qgroup_swapped_block *entry;
4532
4533 parent = *cur;
4534 entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
4535 node);
4536
4537 if (entry->subvol_bytenr < block->subvol_bytenr) {
4538 cur = &(*cur)->rb_left;
4539 } else if (entry->subvol_bytenr > block->subvol_bytenr) {
4540 cur = &(*cur)->rb_right;
4541 } else {
4542 if (entry->subvol_generation !=
4543 block->subvol_generation ||
4544 entry->reloc_bytenr != block->reloc_bytenr ||
4545 entry->reloc_generation !=
4546 block->reloc_generation) {
4547 /*
4548 * Duplicated but mismatch entry found.
4549 * Shouldn't happen.
4550 *
4551 * Marking qgroup inconsistent should be enough
4552 * for end users.
4553 */
4554 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4555 ret = -EEXIST;
4556 }
4557 kfree(block);
4558 goto out_unlock;
4559 }
4560 }
4561 rb_link_node(&block->node, parent, cur);
4562 rb_insert_color(&block->node, &blocks->blocks[level]);
4563 blocks->swapped = true;
4564out_unlock:
4565 spin_unlock(&blocks->lock);
4566out:
4567 if (ret < 0)
4568 qgroup_mark_inconsistent(fs_info);
4569 return ret;
4570}
4571
4572/*
4573 * Check if the tree block is a subtree root, and if so do the needed
4574 * delayed subtree trace for qgroup.
4575 *
4576 * This is called during btrfs_cow_block().
4577 */
4578int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
4579 struct btrfs_root *root,
4580 struct extent_buffer *subvol_eb)
4581{
4582 struct btrfs_fs_info *fs_info = root->fs_info;
4583 struct btrfs_tree_parent_check check = { 0 };
4584 struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
4585 struct btrfs_qgroup_swapped_block *block;
4586 struct extent_buffer *reloc_eb = NULL;
4587 struct rb_node *node;
4588 bool found = false;
4589 bool swapped = false;
4590 int level = btrfs_header_level(subvol_eb);
4591 int ret = 0;
4592 int i;
4593
4594 if (!btrfs_qgroup_full_accounting(fs_info))
4595 return 0;
4596 if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
4597 return 0;
4598
4599 spin_lock(&blocks->lock);
4600 if (!blocks->swapped) {
4601 spin_unlock(&blocks->lock);
4602 return 0;
4603 }
4604 node = blocks->blocks[level].rb_node;
4605
4606 while (node) {
4607 block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
4608 if (block->subvol_bytenr < subvol_eb->start) {
4609 node = node->rb_left;
4610 } else if (block->subvol_bytenr > subvol_eb->start) {
4611 node = node->rb_right;
4612 } else {
4613 found = true;
4614 break;
4615 }
4616 }
4617 if (!found) {
4618 spin_unlock(&blocks->lock);
4619 goto out;
4620 }
4621 /* Found one, remove it from @blocks first and update blocks->swapped */
4622 rb_erase(&block->node, &blocks->blocks[level]);
4623 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4624 if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
4625 swapped = true;
4626 break;
4627 }
4628 }
4629 blocks->swapped = swapped;
4630 spin_unlock(&blocks->lock);
4631
4632 check.level = block->level;
4633 check.transid = block->reloc_generation;
4634 check.has_first_key = true;
4635 memcpy(&check.first_key, &block->first_key, sizeof(check.first_key));
4636
4637 /* Read out reloc subtree root */
4638 reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check);
4639 if (IS_ERR(reloc_eb)) {
4640 ret = PTR_ERR(reloc_eb);
4641 reloc_eb = NULL;
4642 goto free_out;
4643 }
4644 if (!extent_buffer_uptodate(reloc_eb)) {
4645 ret = -EIO;
4646 goto free_out;
4647 }
4648
4649 ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4650 block->last_snapshot, block->trace_leaf);
4651free_out:
4652 kfree(block);
4653 free_extent_buffer(reloc_eb);
4654out:
4655 if (ret < 0) {
4656 btrfs_err_rl(fs_info,
4657 "failed to account subtree at bytenr %llu: %d",
4658 subvol_eb->start, ret);
4659 qgroup_mark_inconsistent(fs_info);
4660 }
4661 return ret;
4662}
4663
4664void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
4665{
4666 struct btrfs_qgroup_extent_record *entry;
4667 struct btrfs_qgroup_extent_record *next;
4668 struct rb_root *root;
4669
4670 root = &trans->delayed_refs.dirty_extent_root;
4671 rbtree_postorder_for_each_entry_safe(entry, next, root, node) {
4672 ulist_free(entry->old_roots);
4673 kfree(entry);
4674 }
4675 *root = RB_ROOT;
4676}
4677
4678void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes)
4679{
4680 if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4681 return;
4682
4683 if (!is_fstree(root))
4684 return;
4685
4686 btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA);
4687}
4688
4689int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
4690 struct btrfs_squota_delta *delta)
4691{
4692 int ret;
4693 struct btrfs_qgroup *qgroup;
4694 struct btrfs_qgroup *qg;
4695 LIST_HEAD(qgroup_list);
4696 u64 root = delta->root;
4697 u64 num_bytes = delta->num_bytes;
4698 const int sign = (delta->is_inc ? 1 : -1);
4699
4700 if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4701 return 0;
4702
4703 if (!is_fstree(root))
4704 return 0;
4705
4706 /* If the extent predates enabling quotas, don't count it. */
4707 if (delta->generation < fs_info->qgroup_enable_gen)
4708 return 0;
4709
4710 spin_lock(&fs_info->qgroup_lock);
4711 qgroup = find_qgroup_rb(fs_info, root);
4712 if (!qgroup) {
4713 ret = -ENOENT;
4714 goto out;
4715 }
4716
4717 ret = 0;
4718 qgroup_iterator_add(&qgroup_list, qgroup);
4719 list_for_each_entry(qg, &qgroup_list, iterator) {
4720 struct btrfs_qgroup_list *glist;
4721
4722 qg->excl += num_bytes * sign;
4723 qg->rfer += num_bytes * sign;
4724 qgroup_dirty(fs_info, qg);
4725
4726 list_for_each_entry(glist, &qg->groups, next_group)
4727 qgroup_iterator_add(&qgroup_list, glist->group);
4728 }
4729 qgroup_iterator_clean(&qgroup_list);
4730
4731out:
4732 spin_unlock(&fs_info->qgroup_lock);
4733 return ret;
4734}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2011 STRATO. All rights reserved.
4 */
5
6#include <linux/sched.h>
7#include <linux/pagemap.h>
8#include <linux/writeback.h>
9#include <linux/blkdev.h>
10#include <linux/rbtree.h>
11#include <linux/slab.h>
12#include <linux/workqueue.h>
13#include <linux/btrfs.h>
14#include <linux/sched/mm.h>
15
16#include "ctree.h"
17#include "transaction.h"
18#include "disk-io.h"
19#include "locking.h"
20#include "ulist.h"
21#include "backref.h"
22#include "extent_io.h"
23#include "qgroup.h"
24#include "block-group.h"
25#include "sysfs.h"
26#include "tree-mod-log.h"
27#include "fs.h"
28#include "accessors.h"
29#include "extent-tree.h"
30#include "root-tree.h"
31#include "tree-checker.h"
32
33enum btrfs_qgroup_mode btrfs_qgroup_mode(struct btrfs_fs_info *fs_info)
34{
35 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
36 return BTRFS_QGROUP_MODE_DISABLED;
37 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE)
38 return BTRFS_QGROUP_MODE_SIMPLE;
39 return BTRFS_QGROUP_MODE_FULL;
40}
41
42bool btrfs_qgroup_enabled(struct btrfs_fs_info *fs_info)
43{
44 return btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_DISABLED;
45}
46
47bool btrfs_qgroup_full_accounting(struct btrfs_fs_info *fs_info)
48{
49 return btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL;
50}
51
52/*
53 * Helpers to access qgroup reservation
54 *
55 * Callers should ensure the lock context and type are valid
56 */
57
58static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
59{
60 u64 ret = 0;
61 int i;
62
63 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
64 ret += qgroup->rsv.values[i];
65
66 return ret;
67}
68
69#ifdef CONFIG_BTRFS_DEBUG
70static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
71{
72 if (type == BTRFS_QGROUP_RSV_DATA)
73 return "data";
74 if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
75 return "meta_pertrans";
76 if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
77 return "meta_prealloc";
78 return NULL;
79}
80#endif
81
82static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
83 struct btrfs_qgroup *qgroup, u64 num_bytes,
84 enum btrfs_qgroup_rsv_type type)
85{
86 trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
87 qgroup->rsv.values[type] += num_bytes;
88}
89
90static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
91 struct btrfs_qgroup *qgroup, u64 num_bytes,
92 enum btrfs_qgroup_rsv_type type)
93{
94 trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
95 if (qgroup->rsv.values[type] >= num_bytes) {
96 qgroup->rsv.values[type] -= num_bytes;
97 return;
98 }
99#ifdef CONFIG_BTRFS_DEBUG
100 WARN_RATELIMIT(1,
101 "qgroup %llu %s reserved space underflow, have %llu to free %llu",
102 qgroup->qgroupid, qgroup_rsv_type_str(type),
103 qgroup->rsv.values[type], num_bytes);
104#endif
105 qgroup->rsv.values[type] = 0;
106}
107
108static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
109 struct btrfs_qgroup *dest,
110 struct btrfs_qgroup *src)
111{
112 int i;
113
114 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
115 qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
116}
117
118static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
119 struct btrfs_qgroup *dest,
120 struct btrfs_qgroup *src)
121{
122 int i;
123
124 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
125 qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
126}
127
128static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
129 int mod)
130{
131 if (qg->old_refcnt < seq)
132 qg->old_refcnt = seq;
133 qg->old_refcnt += mod;
134}
135
136static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
137 int mod)
138{
139 if (qg->new_refcnt < seq)
140 qg->new_refcnt = seq;
141 qg->new_refcnt += mod;
142}
143
144static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
145{
146 if (qg->old_refcnt < seq)
147 return 0;
148 return qg->old_refcnt - seq;
149}
150
151static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
152{
153 if (qg->new_refcnt < seq)
154 return 0;
155 return qg->new_refcnt - seq;
156}
157
158/*
159 * glue structure to represent the relations between qgroups.
160 */
161struct btrfs_qgroup_list {
162 struct list_head next_group;
163 struct list_head next_member;
164 struct btrfs_qgroup *group;
165 struct btrfs_qgroup *member;
166};
167
168static int
169qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
170 int init_flags);
171static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
172
173/* must be called with qgroup_ioctl_lock held */
174static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
175 u64 qgroupid)
176{
177 struct rb_node *n = fs_info->qgroup_tree.rb_node;
178 struct btrfs_qgroup *qgroup;
179
180 while (n) {
181 qgroup = rb_entry(n, struct btrfs_qgroup, node);
182 if (qgroup->qgroupid < qgroupid)
183 n = n->rb_left;
184 else if (qgroup->qgroupid > qgroupid)
185 n = n->rb_right;
186 else
187 return qgroup;
188 }
189 return NULL;
190}
191
192/*
193 * Add qgroup to the filesystem's qgroup tree.
194 *
195 * Must be called with qgroup_lock held and @prealloc preallocated.
196 *
197 * The control on the lifespan of @prealloc would be transferred to this
198 * function, thus caller should no longer touch @prealloc.
199 */
200static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
201 struct btrfs_qgroup *prealloc,
202 u64 qgroupid)
203{
204 struct rb_node **p = &fs_info->qgroup_tree.rb_node;
205 struct rb_node *parent = NULL;
206 struct btrfs_qgroup *qgroup;
207
208 /* Caller must have pre-allocated @prealloc. */
209 ASSERT(prealloc);
210
211 while (*p) {
212 parent = *p;
213 qgroup = rb_entry(parent, struct btrfs_qgroup, node);
214
215 if (qgroup->qgroupid < qgroupid) {
216 p = &(*p)->rb_left;
217 } else if (qgroup->qgroupid > qgroupid) {
218 p = &(*p)->rb_right;
219 } else {
220 kfree(prealloc);
221 return qgroup;
222 }
223 }
224
225 qgroup = prealloc;
226 qgroup->qgroupid = qgroupid;
227 INIT_LIST_HEAD(&qgroup->groups);
228 INIT_LIST_HEAD(&qgroup->members);
229 INIT_LIST_HEAD(&qgroup->dirty);
230 INIT_LIST_HEAD(&qgroup->iterator);
231 INIT_LIST_HEAD(&qgroup->nested_iterator);
232
233 rb_link_node(&qgroup->node, parent, p);
234 rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
235
236 return qgroup;
237}
238
239static void __del_qgroup_rb(struct btrfs_fs_info *fs_info,
240 struct btrfs_qgroup *qgroup)
241{
242 struct btrfs_qgroup_list *list;
243
244 list_del(&qgroup->dirty);
245 while (!list_empty(&qgroup->groups)) {
246 list = list_first_entry(&qgroup->groups,
247 struct btrfs_qgroup_list, next_group);
248 list_del(&list->next_group);
249 list_del(&list->next_member);
250 kfree(list);
251 }
252
253 while (!list_empty(&qgroup->members)) {
254 list = list_first_entry(&qgroup->members,
255 struct btrfs_qgroup_list, next_member);
256 list_del(&list->next_group);
257 list_del(&list->next_member);
258 kfree(list);
259 }
260}
261
262/* must be called with qgroup_lock held */
263static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
264{
265 struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
266
267 if (!qgroup)
268 return -ENOENT;
269
270 rb_erase(&qgroup->node, &fs_info->qgroup_tree);
271 __del_qgroup_rb(fs_info, qgroup);
272 return 0;
273}
274
275/*
276 * Add relation specified by two qgroups.
277 *
278 * Must be called with qgroup_lock held, the ownership of @prealloc is
279 * transferred to this function and caller should not touch it anymore.
280 *
281 * Return: 0 on success
282 * -ENOENT if one of the qgroups is NULL
283 * <0 other errors
284 */
285static int __add_relation_rb(struct btrfs_qgroup_list *prealloc,
286 struct btrfs_qgroup *member,
287 struct btrfs_qgroup *parent)
288{
289 if (!member || !parent) {
290 kfree(prealloc);
291 return -ENOENT;
292 }
293
294 prealloc->group = parent;
295 prealloc->member = member;
296 list_add_tail(&prealloc->next_group, &member->groups);
297 list_add_tail(&prealloc->next_member, &parent->members);
298
299 return 0;
300}
301
302/*
303 * Add relation specified by two qgroup ids.
304 *
305 * Must be called with qgroup_lock held.
306 *
307 * Return: 0 on success
308 * -ENOENT if one of the ids does not exist
309 * <0 other errors
310 */
311static int add_relation_rb(struct btrfs_fs_info *fs_info,
312 struct btrfs_qgroup_list *prealloc,
313 u64 memberid, u64 parentid)
314{
315 struct btrfs_qgroup *member;
316 struct btrfs_qgroup *parent;
317
318 member = find_qgroup_rb(fs_info, memberid);
319 parent = find_qgroup_rb(fs_info, parentid);
320
321 return __add_relation_rb(prealloc, member, parent);
322}
323
324/* Must be called with qgroup_lock held */
325static int del_relation_rb(struct btrfs_fs_info *fs_info,
326 u64 memberid, u64 parentid)
327{
328 struct btrfs_qgroup *member;
329 struct btrfs_qgroup *parent;
330 struct btrfs_qgroup_list *list;
331
332 member = find_qgroup_rb(fs_info, memberid);
333 parent = find_qgroup_rb(fs_info, parentid);
334 if (!member || !parent)
335 return -ENOENT;
336
337 list_for_each_entry(list, &member->groups, next_group) {
338 if (list->group == parent) {
339 list_del(&list->next_group);
340 list_del(&list->next_member);
341 kfree(list);
342 return 0;
343 }
344 }
345 return -ENOENT;
346}
347
348#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
349int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
350 u64 rfer, u64 excl)
351{
352 struct btrfs_qgroup *qgroup;
353
354 qgroup = find_qgroup_rb(fs_info, qgroupid);
355 if (!qgroup)
356 return -EINVAL;
357 if (qgroup->rfer != rfer || qgroup->excl != excl)
358 return -EINVAL;
359 return 0;
360}
361#endif
362
363static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info)
364{
365 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
366 return;
367 fs_info->qgroup_flags |= (BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT |
368 BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
369 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
370}
371
372static void qgroup_read_enable_gen(struct btrfs_fs_info *fs_info,
373 struct extent_buffer *leaf, int slot,
374 struct btrfs_qgroup_status_item *ptr)
375{
376 ASSERT(btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
377 ASSERT(btrfs_item_size(leaf, slot) >= sizeof(*ptr));
378 fs_info->qgroup_enable_gen = btrfs_qgroup_status_enable_gen(leaf, ptr);
379}
380
381/*
382 * The full config is read in one go, only called from open_ctree()
383 * It doesn't use any locking, as at this point we're still single-threaded
384 */
385int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
386{
387 struct btrfs_key key;
388 struct btrfs_key found_key;
389 struct btrfs_root *quota_root = fs_info->quota_root;
390 struct btrfs_path *path = NULL;
391 struct extent_buffer *l;
392 int slot;
393 int ret = 0;
394 u64 flags = 0;
395 u64 rescan_progress = 0;
396
397 if (!fs_info->quota_root)
398 return 0;
399
400 fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
401 if (!fs_info->qgroup_ulist) {
402 ret = -ENOMEM;
403 goto out;
404 }
405
406 path = btrfs_alloc_path();
407 if (!path) {
408 ret = -ENOMEM;
409 goto out;
410 }
411
412 ret = btrfs_sysfs_add_qgroups(fs_info);
413 if (ret < 0)
414 goto out;
415 /* default this to quota off, in case no status key is found */
416 fs_info->qgroup_flags = 0;
417
418 /*
419 * pass 1: read status, all qgroup infos and limits
420 */
421 key.objectid = 0;
422 key.type = 0;
423 key.offset = 0;
424 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
425 if (ret)
426 goto out;
427
428 while (1) {
429 struct btrfs_qgroup *qgroup;
430
431 slot = path->slots[0];
432 l = path->nodes[0];
433 btrfs_item_key_to_cpu(l, &found_key, slot);
434
435 if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
436 struct btrfs_qgroup_status_item *ptr;
437
438 ptr = btrfs_item_ptr(l, slot,
439 struct btrfs_qgroup_status_item);
440
441 if (btrfs_qgroup_status_version(l, ptr) !=
442 BTRFS_QGROUP_STATUS_VERSION) {
443 btrfs_err(fs_info,
444 "old qgroup version, quota disabled");
445 goto out;
446 }
447 fs_info->qgroup_flags = btrfs_qgroup_status_flags(l, ptr);
448 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE) {
449 qgroup_read_enable_gen(fs_info, l, slot, ptr);
450 } else if (btrfs_qgroup_status_generation(l, ptr) != fs_info->generation) {
451 qgroup_mark_inconsistent(fs_info);
452 btrfs_err(fs_info,
453 "qgroup generation mismatch, marked as inconsistent");
454 }
455 rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
456 goto next1;
457 }
458
459 if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
460 found_key.type != BTRFS_QGROUP_LIMIT_KEY)
461 goto next1;
462
463 qgroup = find_qgroup_rb(fs_info, found_key.offset);
464 if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
465 (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
466 btrfs_err(fs_info, "inconsistent qgroup config");
467 qgroup_mark_inconsistent(fs_info);
468 }
469 if (!qgroup) {
470 struct btrfs_qgroup *prealloc;
471
472 prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);
473 if (!prealloc) {
474 ret = -ENOMEM;
475 goto out;
476 }
477 qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
478 }
479 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
480 if (ret < 0)
481 goto out;
482
483 switch (found_key.type) {
484 case BTRFS_QGROUP_INFO_KEY: {
485 struct btrfs_qgroup_info_item *ptr;
486
487 ptr = btrfs_item_ptr(l, slot,
488 struct btrfs_qgroup_info_item);
489 qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
490 qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
491 qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
492 qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
493 /* generation currently unused */
494 break;
495 }
496 case BTRFS_QGROUP_LIMIT_KEY: {
497 struct btrfs_qgroup_limit_item *ptr;
498
499 ptr = btrfs_item_ptr(l, slot,
500 struct btrfs_qgroup_limit_item);
501 qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
502 qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
503 qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
504 qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
505 qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
506 break;
507 }
508 }
509next1:
510 ret = btrfs_next_item(quota_root, path);
511 if (ret < 0)
512 goto out;
513 if (ret)
514 break;
515 }
516 btrfs_release_path(path);
517
518 /*
519 * pass 2: read all qgroup relations
520 */
521 key.objectid = 0;
522 key.type = BTRFS_QGROUP_RELATION_KEY;
523 key.offset = 0;
524 ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
525 if (ret)
526 goto out;
527 while (1) {
528 struct btrfs_qgroup_list *list = NULL;
529
530 slot = path->slots[0];
531 l = path->nodes[0];
532 btrfs_item_key_to_cpu(l, &found_key, slot);
533
534 if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
535 goto next2;
536
537 if (found_key.objectid > found_key.offset) {
538 /* parent <- member, not needed to build config */
539 /* FIXME should we omit the key completely? */
540 goto next2;
541 }
542
543 list = kzalloc(sizeof(*list), GFP_KERNEL);
544 if (!list) {
545 ret = -ENOMEM;
546 goto out;
547 }
548 ret = add_relation_rb(fs_info, list, found_key.objectid,
549 found_key.offset);
550 list = NULL;
551 if (ret == -ENOENT) {
552 btrfs_warn(fs_info,
553 "orphan qgroup relation 0x%llx->0x%llx",
554 found_key.objectid, found_key.offset);
555 ret = 0; /* ignore the error */
556 }
557 if (ret)
558 goto out;
559next2:
560 ret = btrfs_next_item(quota_root, path);
561 if (ret < 0)
562 goto out;
563 if (ret)
564 break;
565 }
566out:
567 btrfs_free_path(path);
568 fs_info->qgroup_flags |= flags;
569 if (ret >= 0) {
570 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)
571 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
572 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
573 ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
574 } else {
575 ulist_free(fs_info->qgroup_ulist);
576 fs_info->qgroup_ulist = NULL;
577 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
578 btrfs_sysfs_del_qgroups(fs_info);
579 }
580
581 return ret < 0 ? ret : 0;
582}
583
584/*
585 * Called in close_ctree() when quota is still enabled. This verifies we don't
586 * leak some reserved space.
587 *
588 * Return false if no reserved space is left.
589 * Return true if some reserved space is leaked.
590 */
591bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info)
592{
593 struct rb_node *node;
594 bool ret = false;
595
596 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
597 return ret;
598 /*
599 * Since we're unmounting, there is no race and no need to grab qgroup
600 * lock. And here we don't go post-order to provide a more user
601 * friendly sorted result.
602 */
603 for (node = rb_first(&fs_info->qgroup_tree); node; node = rb_next(node)) {
604 struct btrfs_qgroup *qgroup;
605 int i;
606
607 qgroup = rb_entry(node, struct btrfs_qgroup, node);
608 for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) {
609 if (qgroup->rsv.values[i]) {
610 ret = true;
611 btrfs_warn(fs_info,
612 "qgroup %hu/%llu has unreleased space, type %d rsv %llu",
613 btrfs_qgroup_level(qgroup->qgroupid),
614 btrfs_qgroup_subvolid(qgroup->qgroupid),
615 i, qgroup->rsv.values[i]);
616 }
617 }
618 }
619 return ret;
620}
621
622/*
623 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
624 * first two are in single-threaded paths.And for the third one, we have set
625 * quota_root to be null with qgroup_lock held before, so it is safe to clean
626 * up the in-memory structures without qgroup_lock held.
627 */
628void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
629{
630 struct rb_node *n;
631 struct btrfs_qgroup *qgroup;
632
633 while ((n = rb_first(&fs_info->qgroup_tree))) {
634 qgroup = rb_entry(n, struct btrfs_qgroup, node);
635 rb_erase(n, &fs_info->qgroup_tree);
636 __del_qgroup_rb(fs_info, qgroup);
637 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
638 kfree(qgroup);
639 }
640 /*
641 * We call btrfs_free_qgroup_config() when unmounting
642 * filesystem and disabling quota, so we set qgroup_ulist
643 * to be null here to avoid double free.
644 */
645 ulist_free(fs_info->qgroup_ulist);
646 fs_info->qgroup_ulist = NULL;
647 btrfs_sysfs_del_qgroups(fs_info);
648}
649
650static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
651 u64 dst)
652{
653 int ret;
654 struct btrfs_root *quota_root = trans->fs_info->quota_root;
655 struct btrfs_path *path;
656 struct btrfs_key key;
657
658 path = btrfs_alloc_path();
659 if (!path)
660 return -ENOMEM;
661
662 key.objectid = src;
663 key.type = BTRFS_QGROUP_RELATION_KEY;
664 key.offset = dst;
665
666 ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
667
668 btrfs_mark_buffer_dirty(trans, path->nodes[0]);
669
670 btrfs_free_path(path);
671 return ret;
672}
673
674static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
675 u64 dst)
676{
677 int ret;
678 struct btrfs_root *quota_root = trans->fs_info->quota_root;
679 struct btrfs_path *path;
680 struct btrfs_key key;
681
682 path = btrfs_alloc_path();
683 if (!path)
684 return -ENOMEM;
685
686 key.objectid = src;
687 key.type = BTRFS_QGROUP_RELATION_KEY;
688 key.offset = dst;
689
690 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
691 if (ret < 0)
692 goto out;
693
694 if (ret > 0) {
695 ret = -ENOENT;
696 goto out;
697 }
698
699 ret = btrfs_del_item(trans, quota_root, path);
700out:
701 btrfs_free_path(path);
702 return ret;
703}
704
705static int add_qgroup_item(struct btrfs_trans_handle *trans,
706 struct btrfs_root *quota_root, u64 qgroupid)
707{
708 int ret;
709 struct btrfs_path *path;
710 struct btrfs_qgroup_info_item *qgroup_info;
711 struct btrfs_qgroup_limit_item *qgroup_limit;
712 struct extent_buffer *leaf;
713 struct btrfs_key key;
714
715 if (btrfs_is_testing(quota_root->fs_info))
716 return 0;
717
718 path = btrfs_alloc_path();
719 if (!path)
720 return -ENOMEM;
721
722 key.objectid = 0;
723 key.type = BTRFS_QGROUP_INFO_KEY;
724 key.offset = qgroupid;
725
726 /*
727 * Avoid a transaction abort by catching -EEXIST here. In that
728 * case, we proceed by re-initializing the existing structure
729 * on disk.
730 */
731
732 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
733 sizeof(*qgroup_info));
734 if (ret && ret != -EEXIST)
735 goto out;
736
737 leaf = path->nodes[0];
738 qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
739 struct btrfs_qgroup_info_item);
740 btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
741 btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
742 btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
743 btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
744 btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
745
746 btrfs_mark_buffer_dirty(trans, leaf);
747
748 btrfs_release_path(path);
749
750 key.type = BTRFS_QGROUP_LIMIT_KEY;
751 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
752 sizeof(*qgroup_limit));
753 if (ret && ret != -EEXIST)
754 goto out;
755
756 leaf = path->nodes[0];
757 qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
758 struct btrfs_qgroup_limit_item);
759 btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
760 btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
761 btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
762 btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
763 btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
764
765 btrfs_mark_buffer_dirty(trans, leaf);
766
767 ret = 0;
768out:
769 btrfs_free_path(path);
770 return ret;
771}
772
773static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
774{
775 int ret;
776 struct btrfs_root *quota_root = trans->fs_info->quota_root;
777 struct btrfs_path *path;
778 struct btrfs_key key;
779
780 path = btrfs_alloc_path();
781 if (!path)
782 return -ENOMEM;
783
784 key.objectid = 0;
785 key.type = BTRFS_QGROUP_INFO_KEY;
786 key.offset = qgroupid;
787 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
788 if (ret < 0)
789 goto out;
790
791 if (ret > 0) {
792 ret = -ENOENT;
793 goto out;
794 }
795
796 ret = btrfs_del_item(trans, quota_root, path);
797 if (ret)
798 goto out;
799
800 btrfs_release_path(path);
801
802 key.type = BTRFS_QGROUP_LIMIT_KEY;
803 ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
804 if (ret < 0)
805 goto out;
806
807 if (ret > 0) {
808 ret = -ENOENT;
809 goto out;
810 }
811
812 ret = btrfs_del_item(trans, quota_root, path);
813
814out:
815 btrfs_free_path(path);
816 return ret;
817}
818
819static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
820 struct btrfs_qgroup *qgroup)
821{
822 struct btrfs_root *quota_root = trans->fs_info->quota_root;
823 struct btrfs_path *path;
824 struct btrfs_key key;
825 struct extent_buffer *l;
826 struct btrfs_qgroup_limit_item *qgroup_limit;
827 int ret;
828 int slot;
829
830 key.objectid = 0;
831 key.type = BTRFS_QGROUP_LIMIT_KEY;
832 key.offset = qgroup->qgroupid;
833
834 path = btrfs_alloc_path();
835 if (!path)
836 return -ENOMEM;
837
838 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
839 if (ret > 0)
840 ret = -ENOENT;
841
842 if (ret)
843 goto out;
844
845 l = path->nodes[0];
846 slot = path->slots[0];
847 qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
848 btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
849 btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
850 btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
851 btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
852 btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
853
854 btrfs_mark_buffer_dirty(trans, l);
855
856out:
857 btrfs_free_path(path);
858 return ret;
859}
860
861static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
862 struct btrfs_qgroup *qgroup)
863{
864 struct btrfs_fs_info *fs_info = trans->fs_info;
865 struct btrfs_root *quota_root = fs_info->quota_root;
866 struct btrfs_path *path;
867 struct btrfs_key key;
868 struct extent_buffer *l;
869 struct btrfs_qgroup_info_item *qgroup_info;
870 int ret;
871 int slot;
872
873 if (btrfs_is_testing(fs_info))
874 return 0;
875
876 key.objectid = 0;
877 key.type = BTRFS_QGROUP_INFO_KEY;
878 key.offset = qgroup->qgroupid;
879
880 path = btrfs_alloc_path();
881 if (!path)
882 return -ENOMEM;
883
884 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
885 if (ret > 0)
886 ret = -ENOENT;
887
888 if (ret)
889 goto out;
890
891 l = path->nodes[0];
892 slot = path->slots[0];
893 qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
894 btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
895 btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
896 btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
897 btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
898 btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
899
900 btrfs_mark_buffer_dirty(trans, l);
901
902out:
903 btrfs_free_path(path);
904 return ret;
905}
906
907static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
908{
909 struct btrfs_fs_info *fs_info = trans->fs_info;
910 struct btrfs_root *quota_root = fs_info->quota_root;
911 struct btrfs_path *path;
912 struct btrfs_key key;
913 struct extent_buffer *l;
914 struct btrfs_qgroup_status_item *ptr;
915 int ret;
916 int slot;
917
918 key.objectid = 0;
919 key.type = BTRFS_QGROUP_STATUS_KEY;
920 key.offset = 0;
921
922 path = btrfs_alloc_path();
923 if (!path)
924 return -ENOMEM;
925
926 ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
927 if (ret > 0)
928 ret = -ENOENT;
929
930 if (ret)
931 goto out;
932
933 l = path->nodes[0];
934 slot = path->slots[0];
935 ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
936 btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags &
937 BTRFS_QGROUP_STATUS_FLAGS_MASK);
938 btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
939 btrfs_set_qgroup_status_rescan(l, ptr,
940 fs_info->qgroup_rescan_progress.objectid);
941
942 btrfs_mark_buffer_dirty(trans, l);
943
944out:
945 btrfs_free_path(path);
946 return ret;
947}
948
949/*
950 * called with qgroup_lock held
951 */
952static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
953 struct btrfs_root *root)
954{
955 struct btrfs_path *path;
956 struct btrfs_key key;
957 struct extent_buffer *leaf = NULL;
958 int ret;
959 int nr = 0;
960
961 path = btrfs_alloc_path();
962 if (!path)
963 return -ENOMEM;
964
965 key.objectid = 0;
966 key.offset = 0;
967 key.type = 0;
968
969 while (1) {
970 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
971 if (ret < 0)
972 goto out;
973 leaf = path->nodes[0];
974 nr = btrfs_header_nritems(leaf);
975 if (!nr)
976 break;
977 /*
978 * delete the leaf one by one
979 * since the whole tree is going
980 * to be deleted.
981 */
982 path->slots[0] = 0;
983 ret = btrfs_del_items(trans, root, path, 0, nr);
984 if (ret)
985 goto out;
986
987 btrfs_release_path(path);
988 }
989 ret = 0;
990out:
991 btrfs_free_path(path);
992 return ret;
993}
994
995int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
996 struct btrfs_ioctl_quota_ctl_args *quota_ctl_args)
997{
998 struct btrfs_root *quota_root;
999 struct btrfs_root *tree_root = fs_info->tree_root;
1000 struct btrfs_path *path = NULL;
1001 struct btrfs_qgroup_status_item *ptr;
1002 struct extent_buffer *leaf;
1003 struct btrfs_key key;
1004 struct btrfs_key found_key;
1005 struct btrfs_qgroup *qgroup = NULL;
1006 struct btrfs_qgroup *prealloc = NULL;
1007 struct btrfs_trans_handle *trans = NULL;
1008 struct ulist *ulist = NULL;
1009 const bool simple = (quota_ctl_args->cmd == BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA);
1010 int ret = 0;
1011 int slot;
1012
1013 /*
1014 * We need to have subvol_sem write locked, to prevent races between
1015 * concurrent tasks trying to enable quotas, because we will unlock
1016 * and relock qgroup_ioctl_lock before setting fs_info->quota_root
1017 * and before setting BTRFS_FS_QUOTA_ENABLED.
1018 */
1019 lockdep_assert_held_write(&fs_info->subvol_sem);
1020
1021 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
1022 btrfs_err(fs_info,
1023 "qgroups are currently unsupported in extent tree v2");
1024 return -EINVAL;
1025 }
1026
1027 mutex_lock(&fs_info->qgroup_ioctl_lock);
1028 if (fs_info->quota_root)
1029 goto out;
1030
1031 ulist = ulist_alloc(GFP_KERNEL);
1032 if (!ulist) {
1033 ret = -ENOMEM;
1034 goto out;
1035 }
1036
1037 ret = btrfs_sysfs_add_qgroups(fs_info);
1038 if (ret < 0)
1039 goto out;
1040
1041 /*
1042 * Unlock qgroup_ioctl_lock before starting the transaction. This is to
1043 * avoid lock acquisition inversion problems (reported by lockdep) between
1044 * qgroup_ioctl_lock and the vfs freeze semaphores, acquired when we
1045 * start a transaction.
1046 * After we started the transaction lock qgroup_ioctl_lock again and
1047 * check if someone else created the quota root in the meanwhile. If so,
1048 * just return success and release the transaction handle.
1049 *
1050 * Also we don't need to worry about someone else calling
1051 * btrfs_sysfs_add_qgroups() after we unlock and getting an error because
1052 * that function returns 0 (success) when the sysfs entries already exist.
1053 */
1054 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1055
1056 /*
1057 * 1 for quota root item
1058 * 1 for BTRFS_QGROUP_STATUS item
1059 *
1060 * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
1061 * per subvolume. However those are not currently reserved since it
1062 * would be a lot of overkill.
1063 */
1064 trans = btrfs_start_transaction(tree_root, 2);
1065
1066 mutex_lock(&fs_info->qgroup_ioctl_lock);
1067 if (IS_ERR(trans)) {
1068 ret = PTR_ERR(trans);
1069 trans = NULL;
1070 goto out;
1071 }
1072
1073 if (fs_info->quota_root)
1074 goto out;
1075
1076 fs_info->qgroup_ulist = ulist;
1077 ulist = NULL;
1078
1079 /*
1080 * initially create the quota tree
1081 */
1082 quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID);
1083 if (IS_ERR(quota_root)) {
1084 ret = PTR_ERR(quota_root);
1085 btrfs_abort_transaction(trans, ret);
1086 goto out;
1087 }
1088
1089 path = btrfs_alloc_path();
1090 if (!path) {
1091 ret = -ENOMEM;
1092 btrfs_abort_transaction(trans, ret);
1093 goto out_free_root;
1094 }
1095
1096 key.objectid = 0;
1097 key.type = BTRFS_QGROUP_STATUS_KEY;
1098 key.offset = 0;
1099
1100 ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
1101 sizeof(*ptr));
1102 if (ret) {
1103 btrfs_abort_transaction(trans, ret);
1104 goto out_free_path;
1105 }
1106
1107 leaf = path->nodes[0];
1108 ptr = btrfs_item_ptr(leaf, path->slots[0],
1109 struct btrfs_qgroup_status_item);
1110 btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
1111 btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
1112 fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON;
1113 if (simple) {
1114 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1115 btrfs_set_qgroup_status_enable_gen(leaf, ptr, trans->transid);
1116 } else {
1117 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1118 }
1119 btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags &
1120 BTRFS_QGROUP_STATUS_FLAGS_MASK);
1121 btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
1122
1123 btrfs_mark_buffer_dirty(trans, leaf);
1124
1125 key.objectid = 0;
1126 key.type = BTRFS_ROOT_REF_KEY;
1127 key.offset = 0;
1128
1129 btrfs_release_path(path);
1130 ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
1131 if (ret > 0)
1132 goto out_add_root;
1133 if (ret < 0) {
1134 btrfs_abort_transaction(trans, ret);
1135 goto out_free_path;
1136 }
1137
1138 while (1) {
1139 slot = path->slots[0];
1140 leaf = path->nodes[0];
1141 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1142
1143 if (found_key.type == BTRFS_ROOT_REF_KEY) {
1144
1145 /* Release locks on tree_root before we access quota_root */
1146 btrfs_release_path(path);
1147
1148 /* We should not have a stray @prealloc pointer. */
1149 ASSERT(prealloc == NULL);
1150 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1151 if (!prealloc) {
1152 ret = -ENOMEM;
1153 btrfs_abort_transaction(trans, ret);
1154 goto out_free_path;
1155 }
1156
1157 ret = add_qgroup_item(trans, quota_root,
1158 found_key.offset);
1159 if (ret) {
1160 btrfs_abort_transaction(trans, ret);
1161 goto out_free_path;
1162 }
1163
1164 qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
1165 prealloc = NULL;
1166 if (IS_ERR(qgroup)) {
1167 ret = PTR_ERR(qgroup);
1168 btrfs_abort_transaction(trans, ret);
1169 goto out_free_path;
1170 }
1171 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1172 if (ret < 0) {
1173 btrfs_abort_transaction(trans, ret);
1174 goto out_free_path;
1175 }
1176 ret = btrfs_search_slot_for_read(tree_root, &found_key,
1177 path, 1, 0);
1178 if (ret < 0) {
1179 btrfs_abort_transaction(trans, ret);
1180 goto out_free_path;
1181 }
1182 if (ret > 0) {
1183 /*
1184 * Shouldn't happen, but in case it does we
1185 * don't need to do the btrfs_next_item, just
1186 * continue.
1187 */
1188 continue;
1189 }
1190 }
1191 ret = btrfs_next_item(tree_root, path);
1192 if (ret < 0) {
1193 btrfs_abort_transaction(trans, ret);
1194 goto out_free_path;
1195 }
1196 if (ret)
1197 break;
1198 }
1199
1200out_add_root:
1201 btrfs_release_path(path);
1202 ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1203 if (ret) {
1204 btrfs_abort_transaction(trans, ret);
1205 goto out_free_path;
1206 }
1207
1208 ASSERT(prealloc == NULL);
1209 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1210 if (!prealloc) {
1211 ret = -ENOMEM;
1212 goto out_free_path;
1213 }
1214 qgroup = add_qgroup_rb(fs_info, prealloc, BTRFS_FS_TREE_OBJECTID);
1215 prealloc = NULL;
1216 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1217 if (ret < 0) {
1218 btrfs_abort_transaction(trans, ret);
1219 goto out_free_path;
1220 }
1221
1222 fs_info->qgroup_enable_gen = trans->transid;
1223
1224 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1225 /*
1226 * Commit the transaction while not holding qgroup_ioctl_lock, to avoid
1227 * a deadlock with tasks concurrently doing other qgroup operations, such
1228 * adding/removing qgroups or adding/deleting qgroup relations for example,
1229 * because all qgroup operations first start or join a transaction and then
1230 * lock the qgroup_ioctl_lock mutex.
1231 * We are safe from a concurrent task trying to enable quotas, by calling
1232 * this function, since we are serialized by fs_info->subvol_sem.
1233 */
1234 ret = btrfs_commit_transaction(trans);
1235 trans = NULL;
1236 mutex_lock(&fs_info->qgroup_ioctl_lock);
1237 if (ret)
1238 goto out_free_path;
1239
1240 /*
1241 * Set quota enabled flag after committing the transaction, to avoid
1242 * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1243 * creation.
1244 */
1245 spin_lock(&fs_info->qgroup_lock);
1246 fs_info->quota_root = quota_root;
1247 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1248 if (simple)
1249 btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA);
1250 spin_unlock(&fs_info->qgroup_lock);
1251
1252 /* Skip rescan for simple qgroups. */
1253 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
1254 goto out_free_path;
1255
1256 ret = qgroup_rescan_init(fs_info, 0, 1);
1257 if (!ret) {
1258 qgroup_rescan_zero_tracking(fs_info);
1259 fs_info->qgroup_rescan_running = true;
1260 btrfs_queue_work(fs_info->qgroup_rescan_workers,
1261 &fs_info->qgroup_rescan_work);
1262 } else {
1263 /*
1264 * We have set both BTRFS_FS_QUOTA_ENABLED and
1265 * BTRFS_QGROUP_STATUS_FLAG_ON, so we can only fail with
1266 * -EINPROGRESS. That can happen because someone started the
1267 * rescan worker by calling quota rescan ioctl before we
1268 * attempted to initialize the rescan worker. Failure due to
1269 * quotas disabled in the meanwhile is not possible, because
1270 * we are holding a write lock on fs_info->subvol_sem, which
1271 * is also acquired when disabling quotas.
1272 * Ignore such error, and any other error would need to undo
1273 * everything we did in the transaction we just committed.
1274 */
1275 ASSERT(ret == -EINPROGRESS);
1276 ret = 0;
1277 }
1278
1279out_free_path:
1280 btrfs_free_path(path);
1281out_free_root:
1282 if (ret)
1283 btrfs_put_root(quota_root);
1284out:
1285 if (ret) {
1286 ulist_free(fs_info->qgroup_ulist);
1287 fs_info->qgroup_ulist = NULL;
1288 btrfs_sysfs_del_qgroups(fs_info);
1289 }
1290 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1291 if (ret && trans)
1292 btrfs_end_transaction(trans);
1293 else if (trans)
1294 ret = btrfs_end_transaction(trans);
1295 ulist_free(ulist);
1296 kfree(prealloc);
1297 return ret;
1298}
1299
1300/*
1301 * It is possible to have outstanding ordered extents which reserved bytes
1302 * before we disabled. We need to fully flush delalloc, ordered extents, and a
1303 * commit to ensure that we don't leak such reservations, only to have them
1304 * come back if we re-enable.
1305 *
1306 * - enable simple quotas
1307 * - reserve space
1308 * - release it, store rsv_bytes in OE
1309 * - disable quotas
1310 * - enable simple quotas (qgroup rsv are all 0)
1311 * - OE finishes
1312 * - run delayed refs
1313 * - free rsv_bytes, resulting in miscounting or even underflow
1314 */
1315static int flush_reservations(struct btrfs_fs_info *fs_info)
1316{
1317 struct btrfs_trans_handle *trans;
1318 int ret;
1319
1320 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
1321 if (ret)
1322 return ret;
1323 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1324 trans = btrfs_join_transaction(fs_info->tree_root);
1325 if (IS_ERR(trans))
1326 return PTR_ERR(trans);
1327 ret = btrfs_commit_transaction(trans);
1328
1329 return ret;
1330}
1331
1332int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
1333{
1334 struct btrfs_root *quota_root;
1335 struct btrfs_trans_handle *trans = NULL;
1336 int ret = 0;
1337
1338 /*
1339 * We need to have subvol_sem write locked to prevent races with
1340 * snapshot creation.
1341 */
1342 lockdep_assert_held_write(&fs_info->subvol_sem);
1343
1344 /*
1345 * Relocation will mess with backrefs, so make sure we have the
1346 * cleaner_mutex held to protect us from relocate.
1347 */
1348 lockdep_assert_held(&fs_info->cleaner_mutex);
1349
1350 mutex_lock(&fs_info->qgroup_ioctl_lock);
1351 if (!fs_info->quota_root)
1352 goto out;
1353
1354 /*
1355 * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to
1356 * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs
1357 * to lock that mutex while holding a transaction handle and the rescan
1358 * worker needs to commit a transaction.
1359 */
1360 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1361
1362 /*
1363 * Request qgroup rescan worker to complete and wait for it. This wait
1364 * must be done before transaction start for quota disable since it may
1365 * deadlock with transaction by the qgroup rescan worker.
1366 */
1367 clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1368 btrfs_qgroup_wait_for_completion(fs_info, false);
1369
1370 /*
1371 * We have nothing held here and no trans handle, just return the error
1372 * if there is one.
1373 */
1374 ret = flush_reservations(fs_info);
1375 if (ret)
1376 return ret;
1377
1378 /*
1379 * 1 For the root item
1380 *
1381 * We should also reserve enough items for the quota tree deletion in
1382 * btrfs_clean_quota_tree but this is not done.
1383 *
1384 * Also, we must always start a transaction without holding the mutex
1385 * qgroup_ioctl_lock, see btrfs_quota_enable().
1386 */
1387 trans = btrfs_start_transaction(fs_info->tree_root, 1);
1388
1389 mutex_lock(&fs_info->qgroup_ioctl_lock);
1390 if (IS_ERR(trans)) {
1391 ret = PTR_ERR(trans);
1392 trans = NULL;
1393 set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1394 goto out;
1395 }
1396
1397 if (!fs_info->quota_root)
1398 goto out;
1399
1400 spin_lock(&fs_info->qgroup_lock);
1401 quota_root = fs_info->quota_root;
1402 fs_info->quota_root = NULL;
1403 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1404 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1405 fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1406 spin_unlock(&fs_info->qgroup_lock);
1407
1408 btrfs_free_qgroup_config(fs_info);
1409
1410 ret = btrfs_clean_quota_tree(trans, quota_root);
1411 if (ret) {
1412 btrfs_abort_transaction(trans, ret);
1413 goto out;
1414 }
1415
1416 ret = btrfs_del_root(trans, "a_root->root_key);
1417 if (ret) {
1418 btrfs_abort_transaction(trans, ret);
1419 goto out;
1420 }
1421
1422 spin_lock(&fs_info->trans_lock);
1423 list_del("a_root->dirty_list);
1424 spin_unlock(&fs_info->trans_lock);
1425
1426 btrfs_tree_lock(quota_root->node);
1427 btrfs_clear_buffer_dirty(trans, quota_root->node);
1428 btrfs_tree_unlock(quota_root->node);
1429 btrfs_free_tree_block(trans, btrfs_root_id(quota_root),
1430 quota_root->node, 0, 1);
1431
1432 btrfs_put_root(quota_root);
1433
1434out:
1435 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1436 if (ret && trans)
1437 btrfs_end_transaction(trans);
1438 else if (trans)
1439 ret = btrfs_commit_transaction(trans);
1440 return ret;
1441}
1442
1443static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1444 struct btrfs_qgroup *qgroup)
1445{
1446 if (list_empty(&qgroup->dirty))
1447 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1448}
1449
1450static void qgroup_iterator_add(struct list_head *head, struct btrfs_qgroup *qgroup)
1451{
1452 if (!list_empty(&qgroup->iterator))
1453 return;
1454
1455 list_add_tail(&qgroup->iterator, head);
1456}
1457
1458static void qgroup_iterator_clean(struct list_head *head)
1459{
1460 while (!list_empty(head)) {
1461 struct btrfs_qgroup *qgroup;
1462
1463 qgroup = list_first_entry(head, struct btrfs_qgroup, iterator);
1464 list_del_init(&qgroup->iterator);
1465 }
1466}
1467
1468/*
1469 * The easy accounting, we're updating qgroup relationship whose child qgroup
1470 * only has exclusive extents.
1471 *
1472 * In this case, all exclusive extents will also be exclusive for parent, so
1473 * excl/rfer just get added/removed.
1474 *
1475 * So is qgroup reservation space, which should also be added/removed to
1476 * parent.
1477 * Or when child tries to release reservation space, parent will underflow its
1478 * reservation (for relationship adding case).
1479 *
1480 * Caller should hold fs_info->qgroup_lock.
1481 */
1482static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, u64 ref_root,
1483 struct btrfs_qgroup *src, int sign)
1484{
1485 struct btrfs_qgroup *qgroup;
1486 struct btrfs_qgroup *cur;
1487 LIST_HEAD(qgroup_list);
1488 u64 num_bytes = src->excl;
1489 int ret = 0;
1490
1491 qgroup = find_qgroup_rb(fs_info, ref_root);
1492 if (!qgroup)
1493 goto out;
1494
1495 qgroup_iterator_add(&qgroup_list, qgroup);
1496 list_for_each_entry(cur, &qgroup_list, iterator) {
1497 struct btrfs_qgroup_list *glist;
1498
1499 qgroup->rfer += sign * num_bytes;
1500 qgroup->rfer_cmpr += sign * num_bytes;
1501
1502 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1503 qgroup->excl += sign * num_bytes;
1504 qgroup->excl_cmpr += sign * num_bytes;
1505
1506 if (sign > 0)
1507 qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1508 else
1509 qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1510 qgroup_dirty(fs_info, qgroup);
1511
1512 /* Append parent qgroups to @qgroup_list. */
1513 list_for_each_entry(glist, &qgroup->groups, next_group)
1514 qgroup_iterator_add(&qgroup_list, glist->group);
1515 }
1516 ret = 0;
1517out:
1518 qgroup_iterator_clean(&qgroup_list);
1519 return ret;
1520}
1521
1522
1523/*
1524 * Quick path for updating qgroup with only excl refs.
1525 *
1526 * In that case, just update all parent will be enough.
1527 * Or we needs to do a full rescan.
1528 * Caller should also hold fs_info->qgroup_lock.
1529 *
1530 * Return 0 for quick update, return >0 for need to full rescan
1531 * and mark INCONSISTENT flag.
1532 * Return < 0 for other error.
1533 */
1534static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1535 u64 src, u64 dst, int sign)
1536{
1537 struct btrfs_qgroup *qgroup;
1538 int ret = 1;
1539 int err = 0;
1540
1541 qgroup = find_qgroup_rb(fs_info, src);
1542 if (!qgroup)
1543 goto out;
1544 if (qgroup->excl == qgroup->rfer) {
1545 ret = 0;
1546 err = __qgroup_excl_accounting(fs_info, dst, qgroup, sign);
1547 if (err < 0) {
1548 ret = err;
1549 goto out;
1550 }
1551 }
1552out:
1553 if (ret)
1554 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1555 return ret;
1556}
1557
1558int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst)
1559{
1560 struct btrfs_fs_info *fs_info = trans->fs_info;
1561 struct btrfs_qgroup *parent;
1562 struct btrfs_qgroup *member;
1563 struct btrfs_qgroup_list *list;
1564 struct btrfs_qgroup_list *prealloc = NULL;
1565 int ret = 0;
1566
1567 /* Check the level of src and dst first */
1568 if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1569 return -EINVAL;
1570
1571 mutex_lock(&fs_info->qgroup_ioctl_lock);
1572 if (!fs_info->quota_root) {
1573 ret = -ENOTCONN;
1574 goto out;
1575 }
1576 member = find_qgroup_rb(fs_info, src);
1577 parent = find_qgroup_rb(fs_info, dst);
1578 if (!member || !parent) {
1579 ret = -EINVAL;
1580 goto out;
1581 }
1582
1583 /* check if such qgroup relation exist firstly */
1584 list_for_each_entry(list, &member->groups, next_group) {
1585 if (list->group == parent) {
1586 ret = -EEXIST;
1587 goto out;
1588 }
1589 }
1590
1591 prealloc = kzalloc(sizeof(*list), GFP_NOFS);
1592 if (!prealloc) {
1593 ret = -ENOMEM;
1594 goto out;
1595 }
1596 ret = add_qgroup_relation_item(trans, src, dst);
1597 if (ret)
1598 goto out;
1599
1600 ret = add_qgroup_relation_item(trans, dst, src);
1601 if (ret) {
1602 del_qgroup_relation_item(trans, src, dst);
1603 goto out;
1604 }
1605
1606 spin_lock(&fs_info->qgroup_lock);
1607 ret = __add_relation_rb(prealloc, member, parent);
1608 prealloc = NULL;
1609 if (ret < 0) {
1610 spin_unlock(&fs_info->qgroup_lock);
1611 goto out;
1612 }
1613 ret = quick_update_accounting(fs_info, src, dst, 1);
1614 spin_unlock(&fs_info->qgroup_lock);
1615out:
1616 kfree(prealloc);
1617 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1618 return ret;
1619}
1620
1621static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1622 u64 dst)
1623{
1624 struct btrfs_fs_info *fs_info = trans->fs_info;
1625 struct btrfs_qgroup *parent;
1626 struct btrfs_qgroup *member;
1627 struct btrfs_qgroup_list *list;
1628 bool found = false;
1629 int ret = 0;
1630 int ret2;
1631
1632 if (!fs_info->quota_root) {
1633 ret = -ENOTCONN;
1634 goto out;
1635 }
1636
1637 member = find_qgroup_rb(fs_info, src);
1638 parent = find_qgroup_rb(fs_info, dst);
1639 /*
1640 * The parent/member pair doesn't exist, then try to delete the dead
1641 * relation items only.
1642 */
1643 if (!member || !parent)
1644 goto delete_item;
1645
1646 /* check if such qgroup relation exist firstly */
1647 list_for_each_entry(list, &member->groups, next_group) {
1648 if (list->group == parent) {
1649 found = true;
1650 break;
1651 }
1652 }
1653
1654delete_item:
1655 ret = del_qgroup_relation_item(trans, src, dst);
1656 if (ret < 0 && ret != -ENOENT)
1657 goto out;
1658 ret2 = del_qgroup_relation_item(trans, dst, src);
1659 if (ret2 < 0 && ret2 != -ENOENT)
1660 goto out;
1661
1662 /* At least one deletion succeeded, return 0 */
1663 if (!ret || !ret2)
1664 ret = 0;
1665
1666 if (found) {
1667 spin_lock(&fs_info->qgroup_lock);
1668 del_relation_rb(fs_info, src, dst);
1669 ret = quick_update_accounting(fs_info, src, dst, -1);
1670 spin_unlock(&fs_info->qgroup_lock);
1671 }
1672out:
1673 return ret;
1674}
1675
1676int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1677 u64 dst)
1678{
1679 struct btrfs_fs_info *fs_info = trans->fs_info;
1680 int ret = 0;
1681
1682 mutex_lock(&fs_info->qgroup_ioctl_lock);
1683 ret = __del_qgroup_relation(trans, src, dst);
1684 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1685
1686 return ret;
1687}
1688
1689int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1690{
1691 struct btrfs_fs_info *fs_info = trans->fs_info;
1692 struct btrfs_root *quota_root;
1693 struct btrfs_qgroup *qgroup;
1694 struct btrfs_qgroup *prealloc = NULL;
1695 int ret = 0;
1696
1697 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
1698 return 0;
1699
1700 mutex_lock(&fs_info->qgroup_ioctl_lock);
1701 if (!fs_info->quota_root) {
1702 ret = -ENOTCONN;
1703 goto out;
1704 }
1705 quota_root = fs_info->quota_root;
1706 qgroup = find_qgroup_rb(fs_info, qgroupid);
1707 if (qgroup) {
1708 ret = -EEXIST;
1709 goto out;
1710 }
1711
1712 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1713 if (!prealloc) {
1714 ret = -ENOMEM;
1715 goto out;
1716 }
1717
1718 ret = add_qgroup_item(trans, quota_root, qgroupid);
1719 if (ret)
1720 goto out;
1721
1722 spin_lock(&fs_info->qgroup_lock);
1723 qgroup = add_qgroup_rb(fs_info, prealloc, qgroupid);
1724 spin_unlock(&fs_info->qgroup_lock);
1725 prealloc = NULL;
1726
1727 ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1728out:
1729 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1730 kfree(prealloc);
1731 return ret;
1732}
1733
1734static bool qgroup_has_usage(struct btrfs_qgroup *qgroup)
1735{
1736 return (qgroup->rfer > 0 || qgroup->rfer_cmpr > 0 ||
1737 qgroup->excl > 0 || qgroup->excl_cmpr > 0 ||
1738 qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] > 0 ||
1739 qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] > 0 ||
1740 qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > 0);
1741}
1742
1743int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1744{
1745 struct btrfs_fs_info *fs_info = trans->fs_info;
1746 struct btrfs_qgroup *qgroup;
1747 struct btrfs_qgroup_list *list;
1748 int ret = 0;
1749
1750 mutex_lock(&fs_info->qgroup_ioctl_lock);
1751 if (!fs_info->quota_root) {
1752 ret = -ENOTCONN;
1753 goto out;
1754 }
1755
1756 qgroup = find_qgroup_rb(fs_info, qgroupid);
1757 if (!qgroup) {
1758 ret = -ENOENT;
1759 goto out;
1760 }
1761
1762 if (is_fstree(qgroupid) && qgroup_has_usage(qgroup)) {
1763 ret = -EBUSY;
1764 goto out;
1765 }
1766
1767 /* Check if there are no children of this qgroup */
1768 if (!list_empty(&qgroup->members)) {
1769 ret = -EBUSY;
1770 goto out;
1771 }
1772
1773 ret = del_qgroup_item(trans, qgroupid);
1774 if (ret && ret != -ENOENT)
1775 goto out;
1776
1777 while (!list_empty(&qgroup->groups)) {
1778 list = list_first_entry(&qgroup->groups,
1779 struct btrfs_qgroup_list, next_group);
1780 ret = __del_qgroup_relation(trans, qgroupid,
1781 list->group->qgroupid);
1782 if (ret)
1783 goto out;
1784 }
1785
1786 spin_lock(&fs_info->qgroup_lock);
1787 del_qgroup_rb(fs_info, qgroupid);
1788 spin_unlock(&fs_info->qgroup_lock);
1789
1790 /*
1791 * Remove the qgroup from sysfs now without holding the qgroup_lock
1792 * spinlock, since the sysfs_remove_group() function needs to take
1793 * the mutex kernfs_mutex through kernfs_remove_by_name_ns().
1794 */
1795 btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1796 kfree(qgroup);
1797out:
1798 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1799 return ret;
1800}
1801
1802int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
1803 struct btrfs_qgroup_limit *limit)
1804{
1805 struct btrfs_fs_info *fs_info = trans->fs_info;
1806 struct btrfs_qgroup *qgroup;
1807 int ret = 0;
1808 /* Sometimes we would want to clear the limit on this qgroup.
1809 * To meet this requirement, we treat the -1 as a special value
1810 * which tell kernel to clear the limit on this qgroup.
1811 */
1812 const u64 CLEAR_VALUE = -1;
1813
1814 mutex_lock(&fs_info->qgroup_ioctl_lock);
1815 if (!fs_info->quota_root) {
1816 ret = -ENOTCONN;
1817 goto out;
1818 }
1819
1820 qgroup = find_qgroup_rb(fs_info, qgroupid);
1821 if (!qgroup) {
1822 ret = -ENOENT;
1823 goto out;
1824 }
1825
1826 spin_lock(&fs_info->qgroup_lock);
1827 if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1828 if (limit->max_rfer == CLEAR_VALUE) {
1829 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1830 limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1831 qgroup->max_rfer = 0;
1832 } else {
1833 qgroup->max_rfer = limit->max_rfer;
1834 }
1835 }
1836 if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1837 if (limit->max_excl == CLEAR_VALUE) {
1838 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1839 limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1840 qgroup->max_excl = 0;
1841 } else {
1842 qgroup->max_excl = limit->max_excl;
1843 }
1844 }
1845 if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1846 if (limit->rsv_rfer == CLEAR_VALUE) {
1847 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1848 limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1849 qgroup->rsv_rfer = 0;
1850 } else {
1851 qgroup->rsv_rfer = limit->rsv_rfer;
1852 }
1853 }
1854 if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1855 if (limit->rsv_excl == CLEAR_VALUE) {
1856 qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1857 limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1858 qgroup->rsv_excl = 0;
1859 } else {
1860 qgroup->rsv_excl = limit->rsv_excl;
1861 }
1862 }
1863 qgroup->lim_flags |= limit->flags;
1864
1865 spin_unlock(&fs_info->qgroup_lock);
1866
1867 ret = update_qgroup_limit_item(trans, qgroup);
1868 if (ret) {
1869 qgroup_mark_inconsistent(fs_info);
1870 btrfs_info(fs_info, "unable to update quota limit for %llu",
1871 qgroupid);
1872 }
1873
1874out:
1875 mutex_unlock(&fs_info->qgroup_ioctl_lock);
1876 return ret;
1877}
1878
1879/*
1880 * Inform qgroup to trace one dirty extent, its info is recorded in @record.
1881 * So qgroup can account it at transaction committing time.
1882 *
1883 * No lock version, caller must acquire delayed ref lock and allocated memory,
1884 * then call btrfs_qgroup_trace_extent_post() after exiting lock context.
1885 *
1886 * Return 0 for success insert
1887 * Return >0 for existing record, caller can free @record safely.
1888 * Error is not possible
1889 */
1890int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1891 struct btrfs_delayed_ref_root *delayed_refs,
1892 struct btrfs_qgroup_extent_record *record)
1893{
1894 struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1895 struct rb_node *parent_node = NULL;
1896 struct btrfs_qgroup_extent_record *entry;
1897 u64 bytenr = record->bytenr;
1898
1899 if (!btrfs_qgroup_full_accounting(fs_info))
1900 return 1;
1901
1902 lockdep_assert_held(&delayed_refs->lock);
1903 trace_btrfs_qgroup_trace_extent(fs_info, record);
1904
1905 while (*p) {
1906 parent_node = *p;
1907 entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1908 node);
1909 if (bytenr < entry->bytenr) {
1910 p = &(*p)->rb_left;
1911 } else if (bytenr > entry->bytenr) {
1912 p = &(*p)->rb_right;
1913 } else {
1914 if (record->data_rsv && !entry->data_rsv) {
1915 entry->data_rsv = record->data_rsv;
1916 entry->data_rsv_refroot =
1917 record->data_rsv_refroot;
1918 }
1919 return 1;
1920 }
1921 }
1922
1923 rb_link_node(&record->node, parent_node, p);
1924 rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1925 return 0;
1926}
1927
1928/*
1929 * Post handler after qgroup_trace_extent_nolock().
1930 *
1931 * NOTE: Current qgroup does the expensive backref walk at transaction
1932 * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming
1933 * new transaction.
1934 * This is designed to allow btrfs_find_all_roots() to get correct new_roots
1935 * result.
1936 *
1937 * However for old_roots there is no need to do backref walk at that time,
1938 * since we search commit roots to walk backref and result will always be
1939 * correct.
1940 *
1941 * Due to the nature of no lock version, we can't do backref there.
1942 * So we must call btrfs_qgroup_trace_extent_post() after exiting
1943 * spinlock context.
1944 *
1945 * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result
1946 * using current root, then we can move all expensive backref walk out of
1947 * transaction committing, but not now as qgroup accounting will be wrong again.
1948 */
1949int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
1950 struct btrfs_qgroup_extent_record *qrecord)
1951{
1952 struct btrfs_backref_walk_ctx ctx = { 0 };
1953 int ret;
1954
1955 if (!btrfs_qgroup_full_accounting(trans->fs_info))
1956 return 0;
1957 /*
1958 * We are always called in a context where we are already holding a
1959 * transaction handle. Often we are called when adding a data delayed
1960 * reference from btrfs_truncate_inode_items() (truncating or unlinking),
1961 * in which case we will be holding a write lock on extent buffer from a
1962 * subvolume tree. In this case we can't allow btrfs_find_all_roots() to
1963 * acquire fs_info->commit_root_sem, because that is a higher level lock
1964 * that must be acquired before locking any extent buffers.
1965 *
1966 * So we want btrfs_find_all_roots() to not acquire the commit_root_sem
1967 * but we can't pass it a non-NULL transaction handle, because otherwise
1968 * it would not use commit roots and would lock extent buffers, causing
1969 * a deadlock if it ends up trying to read lock the same extent buffer
1970 * that was previously write locked at btrfs_truncate_inode_items().
1971 *
1972 * So pass a NULL transaction handle to btrfs_find_all_roots() and
1973 * explicitly tell it to not acquire the commit_root_sem - if we are
1974 * holding a transaction handle we don't need its protection.
1975 */
1976 ASSERT(trans != NULL);
1977
1978 if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
1979 return 0;
1980
1981 ctx.bytenr = qrecord->bytenr;
1982 ctx.fs_info = trans->fs_info;
1983
1984 ret = btrfs_find_all_roots(&ctx, true);
1985 if (ret < 0) {
1986 qgroup_mark_inconsistent(trans->fs_info);
1987 btrfs_warn(trans->fs_info,
1988"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1989 ret);
1990 return 0;
1991 }
1992
1993 /*
1994 * Here we don't need to get the lock of
1995 * trans->transaction->delayed_refs, since inserted qrecord won't
1996 * be deleted, only qrecord->node may be modified (new qrecord insert)
1997 *
1998 * So modifying qrecord->old_roots is safe here
1999 */
2000 qrecord->old_roots = ctx.roots;
2001 return 0;
2002}
2003
2004/*
2005 * Inform qgroup to trace one dirty extent, specified by @bytenr and
2006 * @num_bytes.
2007 * So qgroup can account it at commit trans time.
2008 *
2009 * Better encapsulated version, with memory allocation and backref walk for
2010 * commit roots.
2011 * So this can sleep.
2012 *
2013 * Return 0 if the operation is done.
2014 * Return <0 for error, like memory allocation failure or invalid parameter
2015 * (NULL trans)
2016 */
2017int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2018 u64 num_bytes)
2019{
2020 struct btrfs_fs_info *fs_info = trans->fs_info;
2021 struct btrfs_qgroup_extent_record *record;
2022 struct btrfs_delayed_ref_root *delayed_refs;
2023 int ret;
2024
2025 if (!btrfs_qgroup_full_accounting(fs_info) || bytenr == 0 || num_bytes == 0)
2026 return 0;
2027 record = kzalloc(sizeof(*record), GFP_NOFS);
2028 if (!record)
2029 return -ENOMEM;
2030
2031 delayed_refs = &trans->transaction->delayed_refs;
2032 record->bytenr = bytenr;
2033 record->num_bytes = num_bytes;
2034 record->old_roots = NULL;
2035
2036 spin_lock(&delayed_refs->lock);
2037 ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
2038 spin_unlock(&delayed_refs->lock);
2039 if (ret > 0) {
2040 kfree(record);
2041 return 0;
2042 }
2043 return btrfs_qgroup_trace_extent_post(trans, record);
2044}
2045
2046/*
2047 * Inform qgroup to trace all leaf items of data
2048 *
2049 * Return 0 for success
2050 * Return <0 for error(ENOMEM)
2051 */
2052int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
2053 struct extent_buffer *eb)
2054{
2055 struct btrfs_fs_info *fs_info = trans->fs_info;
2056 int nr = btrfs_header_nritems(eb);
2057 int i, extent_type, ret;
2058 struct btrfs_key key;
2059 struct btrfs_file_extent_item *fi;
2060 u64 bytenr, num_bytes;
2061
2062 /* We can be called directly from walk_up_proc() */
2063 if (!btrfs_qgroup_full_accounting(fs_info))
2064 return 0;
2065
2066 for (i = 0; i < nr; i++) {
2067 btrfs_item_key_to_cpu(eb, &key, i);
2068
2069 if (key.type != BTRFS_EXTENT_DATA_KEY)
2070 continue;
2071
2072 fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2073 /* filter out non qgroup-accountable extents */
2074 extent_type = btrfs_file_extent_type(eb, fi);
2075
2076 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
2077 continue;
2078
2079 bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
2080 if (!bytenr)
2081 continue;
2082
2083 num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
2084
2085 ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes);
2086 if (ret)
2087 return ret;
2088 }
2089 cond_resched();
2090 return 0;
2091}
2092
2093/*
2094 * Walk up the tree from the bottom, freeing leaves and any interior
2095 * nodes which have had all slots visited. If a node (leaf or
2096 * interior) is freed, the node above it will have it's slot
2097 * incremented. The root node will never be freed.
2098 *
2099 * At the end of this function, we should have a path which has all
2100 * slots incremented to the next position for a search. If we need to
2101 * read a new node it will be NULL and the node above it will have the
2102 * correct slot selected for a later read.
2103 *
2104 * If we increment the root nodes slot counter past the number of
2105 * elements, 1 is returned to signal completion of the search.
2106 */
2107static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
2108{
2109 int level = 0;
2110 int nr, slot;
2111 struct extent_buffer *eb;
2112
2113 if (root_level == 0)
2114 return 1;
2115
2116 while (level <= root_level) {
2117 eb = path->nodes[level];
2118 nr = btrfs_header_nritems(eb);
2119 path->slots[level]++;
2120 slot = path->slots[level];
2121 if (slot >= nr || level == 0) {
2122 /*
2123 * Don't free the root - we will detect this
2124 * condition after our loop and return a
2125 * positive value for caller to stop walking the tree.
2126 */
2127 if (level != root_level) {
2128 btrfs_tree_unlock_rw(eb, path->locks[level]);
2129 path->locks[level] = 0;
2130
2131 free_extent_buffer(eb);
2132 path->nodes[level] = NULL;
2133 path->slots[level] = 0;
2134 }
2135 } else {
2136 /*
2137 * We have a valid slot to walk back down
2138 * from. Stop here so caller can process these
2139 * new nodes.
2140 */
2141 break;
2142 }
2143
2144 level++;
2145 }
2146
2147 eb = path->nodes[root_level];
2148 if (path->slots[root_level] >= btrfs_header_nritems(eb))
2149 return 1;
2150
2151 return 0;
2152}
2153
2154/*
2155 * Helper function to trace a subtree tree block swap.
2156 *
2157 * The swap will happen in highest tree block, but there may be a lot of
2158 * tree blocks involved.
2159 *
2160 * For example:
2161 * OO = Old tree blocks
2162 * NN = New tree blocks allocated during balance
2163 *
2164 * File tree (257) Reloc tree for 257
2165 * L2 OO NN
2166 * / \ / \
2167 * L1 OO OO (a) OO NN (a)
2168 * / \ / \ / \ / \
2169 * L0 OO OO OO OO OO OO NN NN
2170 * (b) (c) (b) (c)
2171 *
2172 * When calling qgroup_trace_extent_swap(), we will pass:
2173 * @src_eb = OO(a)
2174 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
2175 * @dst_level = 0
2176 * @root_level = 1
2177 *
2178 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
2179 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
2180 *
2181 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
2182 *
2183 * 1) Tree search from @src_eb
2184 * It should acts as a simplified btrfs_search_slot().
2185 * The key for search can be extracted from @dst_path->nodes[dst_level]
2186 * (first key).
2187 *
2188 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
2189 * NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
2190 * They should be marked during previous (@dst_level = 1) iteration.
2191 *
2192 * 3) Mark file extents in leaves dirty
2193 * We don't have good way to pick out new file extents only.
2194 * So we still follow the old method by scanning all file extents in
2195 * the leave.
2196 *
2197 * This function can free us from keeping two paths, thus later we only need
2198 * to care about how to iterate all new tree blocks in reloc tree.
2199 */
2200static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
2201 struct extent_buffer *src_eb,
2202 struct btrfs_path *dst_path,
2203 int dst_level, int root_level,
2204 bool trace_leaf)
2205{
2206 struct btrfs_key key;
2207 struct btrfs_path *src_path;
2208 struct btrfs_fs_info *fs_info = trans->fs_info;
2209 u32 nodesize = fs_info->nodesize;
2210 int cur_level = root_level;
2211 int ret;
2212
2213 BUG_ON(dst_level > root_level);
2214 /* Level mismatch */
2215 if (btrfs_header_level(src_eb) != root_level)
2216 return -EINVAL;
2217
2218 src_path = btrfs_alloc_path();
2219 if (!src_path) {
2220 ret = -ENOMEM;
2221 goto out;
2222 }
2223
2224 if (dst_level)
2225 btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2226 else
2227 btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2228
2229 /* For src_path */
2230 atomic_inc(&src_eb->refs);
2231 src_path->nodes[root_level] = src_eb;
2232 src_path->slots[root_level] = dst_path->slots[root_level];
2233 src_path->locks[root_level] = 0;
2234
2235 /* A simplified version of btrfs_search_slot() */
2236 while (cur_level >= dst_level) {
2237 struct btrfs_key src_key;
2238 struct btrfs_key dst_key;
2239
2240 if (src_path->nodes[cur_level] == NULL) {
2241 struct extent_buffer *eb;
2242 int parent_slot;
2243
2244 eb = src_path->nodes[cur_level + 1];
2245 parent_slot = src_path->slots[cur_level + 1];
2246
2247 eb = btrfs_read_node_slot(eb, parent_slot);
2248 if (IS_ERR(eb)) {
2249 ret = PTR_ERR(eb);
2250 goto out;
2251 }
2252
2253 src_path->nodes[cur_level] = eb;
2254
2255 btrfs_tree_read_lock(eb);
2256 src_path->locks[cur_level] = BTRFS_READ_LOCK;
2257 }
2258
2259 src_path->slots[cur_level] = dst_path->slots[cur_level];
2260 if (cur_level) {
2261 btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
2262 &dst_key, dst_path->slots[cur_level]);
2263 btrfs_node_key_to_cpu(src_path->nodes[cur_level],
2264 &src_key, src_path->slots[cur_level]);
2265 } else {
2266 btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
2267 &dst_key, dst_path->slots[cur_level]);
2268 btrfs_item_key_to_cpu(src_path->nodes[cur_level],
2269 &src_key, src_path->slots[cur_level]);
2270 }
2271 /* Content mismatch, something went wrong */
2272 if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
2273 ret = -ENOENT;
2274 goto out;
2275 }
2276 cur_level--;
2277 }
2278
2279 /*
2280 * Now both @dst_path and @src_path have been populated, record the tree
2281 * blocks for qgroup accounting.
2282 */
2283 ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
2284 nodesize);
2285 if (ret < 0)
2286 goto out;
2287 ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start,
2288 nodesize);
2289 if (ret < 0)
2290 goto out;
2291
2292 /* Record leaf file extents */
2293 if (dst_level == 0 && trace_leaf) {
2294 ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
2295 if (ret < 0)
2296 goto out;
2297 ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
2298 }
2299out:
2300 btrfs_free_path(src_path);
2301 return ret;
2302}
2303
2304/*
2305 * Helper function to do recursive generation-aware depth-first search, to
2306 * locate all new tree blocks in a subtree of reloc tree.
2307 *
2308 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
2309 * reloc tree
2310 * L2 NN (a)
2311 * / \
2312 * L1 OO NN (b)
2313 * / \ / \
2314 * L0 OO OO OO NN
2315 * (c) (d)
2316 * If we pass:
2317 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
2318 * @cur_level = 1
2319 * @root_level = 1
2320 *
2321 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
2322 * above tree blocks along with their counter parts in file tree.
2323 * While during search, old tree blocks OO(c) will be skipped as tree block swap
2324 * won't affect OO(c).
2325 */
2326static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
2327 struct extent_buffer *src_eb,
2328 struct btrfs_path *dst_path,
2329 int cur_level, int root_level,
2330 u64 last_snapshot, bool trace_leaf)
2331{
2332 struct btrfs_fs_info *fs_info = trans->fs_info;
2333 struct extent_buffer *eb;
2334 bool need_cleanup = false;
2335 int ret = 0;
2336 int i;
2337
2338 /* Level sanity check */
2339 if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
2340 root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
2341 root_level < cur_level) {
2342 btrfs_err_rl(fs_info,
2343 "%s: bad levels, cur_level=%d root_level=%d",
2344 __func__, cur_level, root_level);
2345 return -EUCLEAN;
2346 }
2347
2348 /* Read the tree block if needed */
2349 if (dst_path->nodes[cur_level] == NULL) {
2350 int parent_slot;
2351 u64 child_gen;
2352
2353 /*
2354 * dst_path->nodes[root_level] must be initialized before
2355 * calling this function.
2356 */
2357 if (cur_level == root_level) {
2358 btrfs_err_rl(fs_info,
2359 "%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
2360 __func__, root_level, root_level, cur_level);
2361 return -EUCLEAN;
2362 }
2363
2364 /*
2365 * We need to get child blockptr/gen from parent before we can
2366 * read it.
2367 */
2368 eb = dst_path->nodes[cur_level + 1];
2369 parent_slot = dst_path->slots[cur_level + 1];
2370 child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2371
2372 /* This node is old, no need to trace */
2373 if (child_gen < last_snapshot)
2374 goto out;
2375
2376 eb = btrfs_read_node_slot(eb, parent_slot);
2377 if (IS_ERR(eb)) {
2378 ret = PTR_ERR(eb);
2379 goto out;
2380 }
2381
2382 dst_path->nodes[cur_level] = eb;
2383 dst_path->slots[cur_level] = 0;
2384
2385 btrfs_tree_read_lock(eb);
2386 dst_path->locks[cur_level] = BTRFS_READ_LOCK;
2387 need_cleanup = true;
2388 }
2389
2390 /* Now record this tree block and its counter part for qgroups */
2391 ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
2392 root_level, trace_leaf);
2393 if (ret < 0)
2394 goto cleanup;
2395
2396 eb = dst_path->nodes[cur_level];
2397
2398 if (cur_level > 0) {
2399 /* Iterate all child tree blocks */
2400 for (i = 0; i < btrfs_header_nritems(eb); i++) {
2401 /* Skip old tree blocks as they won't be swapped */
2402 if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2403 continue;
2404 dst_path->slots[cur_level] = i;
2405
2406 /* Recursive call (at most 7 times) */
2407 ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2408 dst_path, cur_level - 1, root_level,
2409 last_snapshot, trace_leaf);
2410 if (ret < 0)
2411 goto cleanup;
2412 }
2413 }
2414
2415cleanup:
2416 if (need_cleanup) {
2417 /* Clean up */
2418 btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2419 dst_path->locks[cur_level]);
2420 free_extent_buffer(dst_path->nodes[cur_level]);
2421 dst_path->nodes[cur_level] = NULL;
2422 dst_path->slots[cur_level] = 0;
2423 dst_path->locks[cur_level] = 0;
2424 }
2425out:
2426 return ret;
2427}
2428
2429static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2430 struct extent_buffer *src_eb,
2431 struct extent_buffer *dst_eb,
2432 u64 last_snapshot, bool trace_leaf)
2433{
2434 struct btrfs_fs_info *fs_info = trans->fs_info;
2435 struct btrfs_path *dst_path = NULL;
2436 int level;
2437 int ret;
2438
2439 if (!btrfs_qgroup_full_accounting(fs_info))
2440 return 0;
2441
2442 /* Wrong parameter order */
2443 if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2444 btrfs_err_rl(fs_info,
2445 "%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2446 btrfs_header_generation(src_eb),
2447 btrfs_header_generation(dst_eb));
2448 return -EUCLEAN;
2449 }
2450
2451 if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2452 ret = -EIO;
2453 goto out;
2454 }
2455
2456 level = btrfs_header_level(dst_eb);
2457 dst_path = btrfs_alloc_path();
2458 if (!dst_path) {
2459 ret = -ENOMEM;
2460 goto out;
2461 }
2462 /* For dst_path */
2463 atomic_inc(&dst_eb->refs);
2464 dst_path->nodes[level] = dst_eb;
2465 dst_path->slots[level] = 0;
2466 dst_path->locks[level] = 0;
2467
2468 /* Do the generation aware breadth-first search */
2469 ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2470 level, last_snapshot, trace_leaf);
2471 if (ret < 0)
2472 goto out;
2473 ret = 0;
2474
2475out:
2476 btrfs_free_path(dst_path);
2477 if (ret < 0)
2478 qgroup_mark_inconsistent(fs_info);
2479 return ret;
2480}
2481
2482/*
2483 * Inform qgroup to trace a whole subtree, including all its child tree
2484 * blocks and data.
2485 * The root tree block is specified by @root_eb.
2486 *
2487 * Normally used by relocation(tree block swap) and subvolume deletion.
2488 *
2489 * Return 0 for success
2490 * Return <0 for error(ENOMEM or tree search error)
2491 */
2492int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2493 struct extent_buffer *root_eb,
2494 u64 root_gen, int root_level)
2495{
2496 struct btrfs_fs_info *fs_info = trans->fs_info;
2497 int ret = 0;
2498 int level;
2499 u8 drop_subptree_thres;
2500 struct extent_buffer *eb = root_eb;
2501 struct btrfs_path *path = NULL;
2502
2503 ASSERT(0 <= root_level && root_level < BTRFS_MAX_LEVEL);
2504 ASSERT(root_eb != NULL);
2505
2506 if (!btrfs_qgroup_full_accounting(fs_info))
2507 return 0;
2508
2509 spin_lock(&fs_info->qgroup_lock);
2510 drop_subptree_thres = fs_info->qgroup_drop_subtree_thres;
2511 spin_unlock(&fs_info->qgroup_lock);
2512
2513 /*
2514 * This function only gets called for snapshot drop, if we hit a high
2515 * node here, it means we are going to change ownership for quite a lot
2516 * of extents, which will greatly slow down btrfs_commit_transaction().
2517 *
2518 * So here if we find a high tree here, we just skip the accounting and
2519 * mark qgroup inconsistent.
2520 */
2521 if (root_level >= drop_subptree_thres) {
2522 qgroup_mark_inconsistent(fs_info);
2523 return 0;
2524 }
2525
2526 if (!extent_buffer_uptodate(root_eb)) {
2527 struct btrfs_tree_parent_check check = {
2528 .has_first_key = false,
2529 .transid = root_gen,
2530 .level = root_level
2531 };
2532
2533 ret = btrfs_read_extent_buffer(root_eb, &check);
2534 if (ret)
2535 goto out;
2536 }
2537
2538 if (root_level == 0) {
2539 ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2540 goto out;
2541 }
2542
2543 path = btrfs_alloc_path();
2544 if (!path)
2545 return -ENOMEM;
2546
2547 /*
2548 * Walk down the tree. Missing extent blocks are filled in as
2549 * we go. Metadata is accounted every time we read a new
2550 * extent block.
2551 *
2552 * When we reach a leaf, we account for file extent items in it,
2553 * walk back up the tree (adjusting slot pointers as we go)
2554 * and restart the search process.
2555 */
2556 atomic_inc(&root_eb->refs); /* For path */
2557 path->nodes[root_level] = root_eb;
2558 path->slots[root_level] = 0;
2559 path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2560walk_down:
2561 level = root_level;
2562 while (level >= 0) {
2563 if (path->nodes[level] == NULL) {
2564 int parent_slot;
2565 u64 child_bytenr;
2566
2567 /*
2568 * We need to get child blockptr from parent before we
2569 * can read it.
2570 */
2571 eb = path->nodes[level + 1];
2572 parent_slot = path->slots[level + 1];
2573 child_bytenr = btrfs_node_blockptr(eb, parent_slot);
2574
2575 eb = btrfs_read_node_slot(eb, parent_slot);
2576 if (IS_ERR(eb)) {
2577 ret = PTR_ERR(eb);
2578 goto out;
2579 }
2580
2581 path->nodes[level] = eb;
2582 path->slots[level] = 0;
2583
2584 btrfs_tree_read_lock(eb);
2585 path->locks[level] = BTRFS_READ_LOCK;
2586
2587 ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2588 fs_info->nodesize);
2589 if (ret)
2590 goto out;
2591 }
2592
2593 if (level == 0) {
2594 ret = btrfs_qgroup_trace_leaf_items(trans,
2595 path->nodes[level]);
2596 if (ret)
2597 goto out;
2598
2599 /* Nonzero return here means we completed our search */
2600 ret = adjust_slots_upwards(path, root_level);
2601 if (ret)
2602 break;
2603
2604 /* Restart search with new slots */
2605 goto walk_down;
2606 }
2607
2608 level--;
2609 }
2610
2611 ret = 0;
2612out:
2613 btrfs_free_path(path);
2614
2615 return ret;
2616}
2617
2618static void qgroup_iterator_nested_add(struct list_head *head, struct btrfs_qgroup *qgroup)
2619{
2620 if (!list_empty(&qgroup->nested_iterator))
2621 return;
2622
2623 list_add_tail(&qgroup->nested_iterator, head);
2624}
2625
2626static void qgroup_iterator_nested_clean(struct list_head *head)
2627{
2628 while (!list_empty(head)) {
2629 struct btrfs_qgroup *qgroup;
2630
2631 qgroup = list_first_entry(head, struct btrfs_qgroup, nested_iterator);
2632 list_del_init(&qgroup->nested_iterator);
2633 }
2634}
2635
2636#define UPDATE_NEW 0
2637#define UPDATE_OLD 1
2638/*
2639 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2640 */
2641static void qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2642 struct ulist *roots, struct list_head *qgroups,
2643 u64 seq, int update_old)
2644{
2645 struct ulist_node *unode;
2646 struct ulist_iterator uiter;
2647 struct btrfs_qgroup *qg;
2648
2649 if (!roots)
2650 return;
2651 ULIST_ITER_INIT(&uiter);
2652 while ((unode = ulist_next(roots, &uiter))) {
2653 LIST_HEAD(tmp);
2654
2655 qg = find_qgroup_rb(fs_info, unode->val);
2656 if (!qg)
2657 continue;
2658
2659 qgroup_iterator_nested_add(qgroups, qg);
2660 qgroup_iterator_add(&tmp, qg);
2661 list_for_each_entry(qg, &tmp, iterator) {
2662 struct btrfs_qgroup_list *glist;
2663
2664 if (update_old)
2665 btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2666 else
2667 btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2668
2669 list_for_each_entry(glist, &qg->groups, next_group) {
2670 qgroup_iterator_nested_add(qgroups, glist->group);
2671 qgroup_iterator_add(&tmp, glist->group);
2672 }
2673 }
2674 qgroup_iterator_clean(&tmp);
2675 }
2676}
2677
2678/*
2679 * Update qgroup rfer/excl counters.
2680 * Rfer update is easy, codes can explain themselves.
2681 *
2682 * Excl update is tricky, the update is split into 2 parts.
2683 * Part 1: Possible exclusive <-> sharing detect:
2684 * | A | !A |
2685 * -------------------------------------
2686 * B | * | - |
2687 * -------------------------------------
2688 * !B | + | ** |
2689 * -------------------------------------
2690 *
2691 * Conditions:
2692 * A: cur_old_roots < nr_old_roots (not exclusive before)
2693 * !A: cur_old_roots == nr_old_roots (possible exclusive before)
2694 * B: cur_new_roots < nr_new_roots (not exclusive now)
2695 * !B: cur_new_roots == nr_new_roots (possible exclusive now)
2696 *
2697 * Results:
2698 * +: Possible sharing -> exclusive -: Possible exclusive -> sharing
2699 * *: Definitely not changed. **: Possible unchanged.
2700 *
2701 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2702 *
2703 * To make the logic clear, we first use condition A and B to split
2704 * combination into 4 results.
2705 *
2706 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2707 * only on variant maybe 0.
2708 *
2709 * Lastly, check result **, since there are 2 variants maybe 0, split them
2710 * again(2x2).
2711 * But this time we don't need to consider other things, the codes and logic
2712 * is easy to understand now.
2713 */
2714static void qgroup_update_counters(struct btrfs_fs_info *fs_info,
2715 struct list_head *qgroups, u64 nr_old_roots,
2716 u64 nr_new_roots, u64 num_bytes, u64 seq)
2717{
2718 struct btrfs_qgroup *qg;
2719
2720 list_for_each_entry(qg, qgroups, nested_iterator) {
2721 u64 cur_new_count, cur_old_count;
2722 bool dirty = false;
2723
2724 cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2725 cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2726
2727 trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2728 cur_new_count);
2729
2730 /* Rfer update part */
2731 if (cur_old_count == 0 && cur_new_count > 0) {
2732 qg->rfer += num_bytes;
2733 qg->rfer_cmpr += num_bytes;
2734 dirty = true;
2735 }
2736 if (cur_old_count > 0 && cur_new_count == 0) {
2737 qg->rfer -= num_bytes;
2738 qg->rfer_cmpr -= num_bytes;
2739 dirty = true;
2740 }
2741
2742 /* Excl update part */
2743 /* Exclusive/none -> shared case */
2744 if (cur_old_count == nr_old_roots &&
2745 cur_new_count < nr_new_roots) {
2746 /* Exclusive -> shared */
2747 if (cur_old_count != 0) {
2748 qg->excl -= num_bytes;
2749 qg->excl_cmpr -= num_bytes;
2750 dirty = true;
2751 }
2752 }
2753
2754 /* Shared -> exclusive/none case */
2755 if (cur_old_count < nr_old_roots &&
2756 cur_new_count == nr_new_roots) {
2757 /* Shared->exclusive */
2758 if (cur_new_count != 0) {
2759 qg->excl += num_bytes;
2760 qg->excl_cmpr += num_bytes;
2761 dirty = true;
2762 }
2763 }
2764
2765 /* Exclusive/none -> exclusive/none case */
2766 if (cur_old_count == nr_old_roots &&
2767 cur_new_count == nr_new_roots) {
2768 if (cur_old_count == 0) {
2769 /* None -> exclusive/none */
2770
2771 if (cur_new_count != 0) {
2772 /* None -> exclusive */
2773 qg->excl += num_bytes;
2774 qg->excl_cmpr += num_bytes;
2775 dirty = true;
2776 }
2777 /* None -> none, nothing changed */
2778 } else {
2779 /* Exclusive -> exclusive/none */
2780
2781 if (cur_new_count == 0) {
2782 /* Exclusive -> none */
2783 qg->excl -= num_bytes;
2784 qg->excl_cmpr -= num_bytes;
2785 dirty = true;
2786 }
2787 /* Exclusive -> exclusive, nothing changed */
2788 }
2789 }
2790
2791 if (dirty)
2792 qgroup_dirty(fs_info, qg);
2793 }
2794}
2795
2796/*
2797 * Check if the @roots potentially is a list of fs tree roots
2798 *
2799 * Return 0 for definitely not a fs/subvol tree roots ulist
2800 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2801 * one as well)
2802 */
2803static int maybe_fs_roots(struct ulist *roots)
2804{
2805 struct ulist_node *unode;
2806 struct ulist_iterator uiter;
2807
2808 /* Empty one, still possible for fs roots */
2809 if (!roots || roots->nnodes == 0)
2810 return 1;
2811
2812 ULIST_ITER_INIT(&uiter);
2813 unode = ulist_next(roots, &uiter);
2814 if (!unode)
2815 return 1;
2816
2817 /*
2818 * If it contains fs tree roots, then it must belong to fs/subvol
2819 * trees.
2820 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2821 */
2822 return is_fstree(unode->val);
2823}
2824
2825int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2826 u64 num_bytes, struct ulist *old_roots,
2827 struct ulist *new_roots)
2828{
2829 struct btrfs_fs_info *fs_info = trans->fs_info;
2830 LIST_HEAD(qgroups);
2831 u64 seq;
2832 u64 nr_new_roots = 0;
2833 u64 nr_old_roots = 0;
2834 int ret = 0;
2835
2836 /*
2837 * If quotas get disabled meanwhile, the resources need to be freed and
2838 * we can't just exit here.
2839 */
2840 if (!btrfs_qgroup_full_accounting(fs_info) ||
2841 fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
2842 goto out_free;
2843
2844 if (new_roots) {
2845 if (!maybe_fs_roots(new_roots))
2846 goto out_free;
2847 nr_new_roots = new_roots->nnodes;
2848 }
2849 if (old_roots) {
2850 if (!maybe_fs_roots(old_roots))
2851 goto out_free;
2852 nr_old_roots = old_roots->nnodes;
2853 }
2854
2855 /* Quick exit, either not fs tree roots, or won't affect any qgroup */
2856 if (nr_old_roots == 0 && nr_new_roots == 0)
2857 goto out_free;
2858
2859 trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2860 num_bytes, nr_old_roots, nr_new_roots);
2861
2862 mutex_lock(&fs_info->qgroup_rescan_lock);
2863 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2864 if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2865 mutex_unlock(&fs_info->qgroup_rescan_lock);
2866 ret = 0;
2867 goto out_free;
2868 }
2869 }
2870 mutex_unlock(&fs_info->qgroup_rescan_lock);
2871
2872 spin_lock(&fs_info->qgroup_lock);
2873 seq = fs_info->qgroup_seq;
2874
2875 /* Update old refcnts using old_roots */
2876 qgroup_update_refcnt(fs_info, old_roots, &qgroups, seq, UPDATE_OLD);
2877
2878 /* Update new refcnts using new_roots */
2879 qgroup_update_refcnt(fs_info, new_roots, &qgroups, seq, UPDATE_NEW);
2880
2881 qgroup_update_counters(fs_info, &qgroups, nr_old_roots, nr_new_roots,
2882 num_bytes, seq);
2883
2884 /*
2885 * We're done using the iterator, release all its qgroups while holding
2886 * fs_info->qgroup_lock so that we don't race with btrfs_remove_qgroup()
2887 * and trigger use-after-free accesses to qgroups.
2888 */
2889 qgroup_iterator_nested_clean(&qgroups);
2890
2891 /*
2892 * Bump qgroup_seq to avoid seq overlap
2893 */
2894 fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2895 spin_unlock(&fs_info->qgroup_lock);
2896out_free:
2897 ulist_free(old_roots);
2898 ulist_free(new_roots);
2899 return ret;
2900}
2901
2902int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2903{
2904 struct btrfs_fs_info *fs_info = trans->fs_info;
2905 struct btrfs_qgroup_extent_record *record;
2906 struct btrfs_delayed_ref_root *delayed_refs;
2907 struct ulist *new_roots = NULL;
2908 struct rb_node *node;
2909 u64 num_dirty_extents = 0;
2910 u64 qgroup_to_skip;
2911 int ret = 0;
2912
2913 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
2914 return 0;
2915
2916 delayed_refs = &trans->transaction->delayed_refs;
2917 qgroup_to_skip = delayed_refs->qgroup_to_skip;
2918 while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2919 record = rb_entry(node, struct btrfs_qgroup_extent_record,
2920 node);
2921
2922 num_dirty_extents++;
2923 trace_btrfs_qgroup_account_extents(fs_info, record);
2924
2925 if (!ret && !(fs_info->qgroup_flags &
2926 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) {
2927 struct btrfs_backref_walk_ctx ctx = { 0 };
2928
2929 ctx.bytenr = record->bytenr;
2930 ctx.fs_info = fs_info;
2931
2932 /*
2933 * Old roots should be searched when inserting qgroup
2934 * extent record.
2935 *
2936 * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case,
2937 * we may have some record inserted during
2938 * NO_ACCOUNTING (thus no old_roots populated), but
2939 * later we start rescan, which clears NO_ACCOUNTING,
2940 * leaving some inserted records without old_roots
2941 * populated.
2942 *
2943 * Those cases are rare and should not cause too much
2944 * time spent during commit_transaction().
2945 */
2946 if (!record->old_roots) {
2947 /* Search commit root to find old_roots */
2948 ret = btrfs_find_all_roots(&ctx, false);
2949 if (ret < 0)
2950 goto cleanup;
2951 record->old_roots = ctx.roots;
2952 ctx.roots = NULL;
2953 }
2954
2955 /*
2956 * Use BTRFS_SEQ_LAST as time_seq to do special search,
2957 * which doesn't lock tree or delayed_refs and search
2958 * current root. It's safe inside commit_transaction().
2959 */
2960 ctx.trans = trans;
2961 ctx.time_seq = BTRFS_SEQ_LAST;
2962 ret = btrfs_find_all_roots(&ctx, false);
2963 if (ret < 0)
2964 goto cleanup;
2965 new_roots = ctx.roots;
2966 if (qgroup_to_skip) {
2967 ulist_del(new_roots, qgroup_to_skip, 0);
2968 ulist_del(record->old_roots, qgroup_to_skip,
2969 0);
2970 }
2971 ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2972 record->num_bytes,
2973 record->old_roots,
2974 new_roots);
2975 record->old_roots = NULL;
2976 new_roots = NULL;
2977 }
2978 /* Free the reserved data space */
2979 btrfs_qgroup_free_refroot(fs_info,
2980 record->data_rsv_refroot,
2981 record->data_rsv,
2982 BTRFS_QGROUP_RSV_DATA);
2983cleanup:
2984 ulist_free(record->old_roots);
2985 ulist_free(new_roots);
2986 new_roots = NULL;
2987 rb_erase(node, &delayed_refs->dirty_extent_root);
2988 kfree(record);
2989
2990 }
2991 trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2992 num_dirty_extents);
2993 return ret;
2994}
2995
2996/*
2997 * Writes all changed qgroups to disk.
2998 * Called by the transaction commit path and the qgroup assign ioctl.
2999 */
3000int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
3001{
3002 struct btrfs_fs_info *fs_info = trans->fs_info;
3003 int ret = 0;
3004
3005 /*
3006 * In case we are called from the qgroup assign ioctl, assert that we
3007 * are holding the qgroup_ioctl_lock, otherwise we can race with a quota
3008 * disable operation (ioctl) and access a freed quota root.
3009 */
3010 if (trans->transaction->state != TRANS_STATE_COMMIT_DOING)
3011 lockdep_assert_held(&fs_info->qgroup_ioctl_lock);
3012
3013 if (!fs_info->quota_root)
3014 return ret;
3015
3016 spin_lock(&fs_info->qgroup_lock);
3017 while (!list_empty(&fs_info->dirty_qgroups)) {
3018 struct btrfs_qgroup *qgroup;
3019 qgroup = list_first_entry(&fs_info->dirty_qgroups,
3020 struct btrfs_qgroup, dirty);
3021 list_del_init(&qgroup->dirty);
3022 spin_unlock(&fs_info->qgroup_lock);
3023 ret = update_qgroup_info_item(trans, qgroup);
3024 if (ret)
3025 qgroup_mark_inconsistent(fs_info);
3026 ret = update_qgroup_limit_item(trans, qgroup);
3027 if (ret)
3028 qgroup_mark_inconsistent(fs_info);
3029 spin_lock(&fs_info->qgroup_lock);
3030 }
3031 if (btrfs_qgroup_enabled(fs_info))
3032 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
3033 else
3034 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
3035 spin_unlock(&fs_info->qgroup_lock);
3036
3037 ret = update_qgroup_status_item(trans);
3038 if (ret)
3039 qgroup_mark_inconsistent(fs_info);
3040
3041 return ret;
3042}
3043
3044int btrfs_qgroup_check_inherit(struct btrfs_fs_info *fs_info,
3045 struct btrfs_qgroup_inherit *inherit,
3046 size_t size)
3047{
3048 if (!btrfs_qgroup_enabled(fs_info))
3049 return 0;
3050 if (inherit->flags & ~BTRFS_QGROUP_INHERIT_FLAGS_SUPP)
3051 return -EOPNOTSUPP;
3052 if (size < sizeof(*inherit) || size > PAGE_SIZE)
3053 return -EINVAL;
3054
3055 /*
3056 * In the past we allowed btrfs_qgroup_inherit to specify to copy
3057 * rfer/excl numbers directly from other qgroups. This behavior has
3058 * been disabled in userspace for a very long time, but here we should
3059 * also disable it in kernel, as this behavior is known to mark qgroup
3060 * inconsistent, and a rescan would wipe out the changes anyway.
3061 *
3062 * Reject any btrfs_qgroup_inherit with num_ref_copies or num_excl_copies.
3063 */
3064 if (inherit->num_ref_copies > 0 || inherit->num_excl_copies > 0)
3065 return -EINVAL;
3066
3067 if (inherit->num_qgroups > PAGE_SIZE)
3068 return -EINVAL;
3069
3070 if (size != struct_size(inherit, qgroups, inherit->num_qgroups))
3071 return -EINVAL;
3072
3073 /*
3074 * Now check all the remaining qgroups, they should all:
3075 *
3076 * - Exist
3077 * - Be higher level qgroups.
3078 */
3079 for (int i = 0; i < inherit->num_qgroups; i++) {
3080 struct btrfs_qgroup *qgroup;
3081 u64 qgroupid = inherit->qgroups[i];
3082
3083 if (btrfs_qgroup_level(qgroupid) == 0)
3084 return -EINVAL;
3085
3086 spin_lock(&fs_info->qgroup_lock);
3087 qgroup = find_qgroup_rb(fs_info, qgroupid);
3088 if (!qgroup) {
3089 spin_unlock(&fs_info->qgroup_lock);
3090 return -ENOENT;
3091 }
3092 spin_unlock(&fs_info->qgroup_lock);
3093 }
3094 return 0;
3095}
3096
3097static int qgroup_auto_inherit(struct btrfs_fs_info *fs_info,
3098 u64 inode_rootid,
3099 struct btrfs_qgroup_inherit **inherit)
3100{
3101 int i = 0;
3102 u64 num_qgroups = 0;
3103 struct btrfs_qgroup *inode_qg;
3104 struct btrfs_qgroup_list *qg_list;
3105 struct btrfs_qgroup_inherit *res;
3106 size_t struct_sz;
3107 u64 *qgids;
3108
3109 if (*inherit)
3110 return -EEXIST;
3111
3112 inode_qg = find_qgroup_rb(fs_info, inode_rootid);
3113 if (!inode_qg)
3114 return -ENOENT;
3115
3116 num_qgroups = list_count_nodes(&inode_qg->groups);
3117
3118 if (!num_qgroups)
3119 return 0;
3120
3121 struct_sz = struct_size(res, qgroups, num_qgroups);
3122 if (struct_sz == SIZE_MAX)
3123 return -ERANGE;
3124
3125 res = kzalloc(struct_sz, GFP_NOFS);
3126 if (!res)
3127 return -ENOMEM;
3128 res->num_qgroups = num_qgroups;
3129 qgids = res->qgroups;
3130
3131 list_for_each_entry(qg_list, &inode_qg->groups, next_group)
3132 qgids[i] = qg_list->group->qgroupid;
3133
3134 *inherit = res;
3135 return 0;
3136}
3137
3138/*
3139 * Check if we can skip rescan when inheriting qgroups. If @src has a single
3140 * @parent, and that @parent is owning all its bytes exclusively, we can skip
3141 * the full rescan, by just adding nodesize to the @parent's excl/rfer.
3142 *
3143 * Return <0 for fatal errors (like srcid/parentid has no qgroup).
3144 * Return 0 if a quick inherit is done.
3145 * Return >0 if a quick inherit is not possible, and a full rescan is needed.
3146 */
3147static int qgroup_snapshot_quick_inherit(struct btrfs_fs_info *fs_info,
3148 u64 srcid, u64 parentid)
3149{
3150 struct btrfs_qgroup *src;
3151 struct btrfs_qgroup *parent;
3152 struct btrfs_qgroup_list *list;
3153 int nr_parents = 0;
3154
3155 src = find_qgroup_rb(fs_info, srcid);
3156 if (!src)
3157 return -ENOENT;
3158 parent = find_qgroup_rb(fs_info, parentid);
3159 if (!parent)
3160 return -ENOENT;
3161
3162 /*
3163 * Source has no parent qgroup, but our new qgroup would have one.
3164 * Qgroup numbers would become inconsistent.
3165 */
3166 if (list_empty(&src->groups))
3167 return 1;
3168
3169 list_for_each_entry(list, &src->groups, next_group) {
3170 /* The parent is not the same, quick update is not possible. */
3171 if (list->group->qgroupid != parentid)
3172 return 1;
3173 nr_parents++;
3174 /*
3175 * More than one parent qgroup, we can't be sure about accounting
3176 * consistency.
3177 */
3178 if (nr_parents > 1)
3179 return 1;
3180 }
3181
3182 /*
3183 * The parent is not exclusively owning all its bytes. We're not sure
3184 * if the source has any bytes not fully owned by the parent.
3185 */
3186 if (parent->excl != parent->rfer)
3187 return 1;
3188
3189 parent->excl += fs_info->nodesize;
3190 parent->rfer += fs_info->nodesize;
3191 return 0;
3192}
3193
3194/*
3195 * Copy the accounting information between qgroups. This is necessary
3196 * when a snapshot or a subvolume is created. Throwing an error will
3197 * cause a transaction abort so we take extra care here to only error
3198 * when a readonly fs is a reasonable outcome.
3199 */
3200int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
3201 u64 objectid, u64 inode_rootid,
3202 struct btrfs_qgroup_inherit *inherit)
3203{
3204 int ret = 0;
3205 int i;
3206 u64 *i_qgroups;
3207 bool committing = false;
3208 struct btrfs_fs_info *fs_info = trans->fs_info;
3209 struct btrfs_root *quota_root;
3210 struct btrfs_qgroup *srcgroup;
3211 struct btrfs_qgroup *dstgroup;
3212 struct btrfs_qgroup *prealloc;
3213 struct btrfs_qgroup_list **qlist_prealloc = NULL;
3214 bool free_inherit = false;
3215 bool need_rescan = false;
3216 u32 level_size = 0;
3217 u64 nums;
3218
3219 prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
3220 if (!prealloc)
3221 return -ENOMEM;
3222
3223 /*
3224 * There are only two callers of this function.
3225 *
3226 * One in create_subvol() in the ioctl context, which needs to hold
3227 * the qgroup_ioctl_lock.
3228 *
3229 * The other one in create_pending_snapshot() where no other qgroup
3230 * code can modify the fs as they all need to either start a new trans
3231 * or hold a trans handler, thus we don't need to hold
3232 * qgroup_ioctl_lock.
3233 * This would avoid long and complex lock chain and make lockdep happy.
3234 */
3235 spin_lock(&fs_info->trans_lock);
3236 if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
3237 committing = true;
3238 spin_unlock(&fs_info->trans_lock);
3239
3240 if (!committing)
3241 mutex_lock(&fs_info->qgroup_ioctl_lock);
3242 if (!btrfs_qgroup_enabled(fs_info))
3243 goto out;
3244
3245 quota_root = fs_info->quota_root;
3246 if (!quota_root) {
3247 ret = -EINVAL;
3248 goto out;
3249 }
3250
3251 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && !inherit) {
3252 ret = qgroup_auto_inherit(fs_info, inode_rootid, &inherit);
3253 if (ret)
3254 goto out;
3255 free_inherit = true;
3256 }
3257
3258 if (inherit) {
3259 i_qgroups = (u64 *)(inherit + 1);
3260 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
3261 2 * inherit->num_excl_copies;
3262 for (i = 0; i < nums; ++i) {
3263 srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
3264
3265 /*
3266 * Zero out invalid groups so we can ignore
3267 * them later.
3268 */
3269 if (!srcgroup ||
3270 ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
3271 *i_qgroups = 0ULL;
3272
3273 ++i_qgroups;
3274 }
3275 }
3276
3277 /*
3278 * create a tracking group for the subvol itself
3279 */
3280 ret = add_qgroup_item(trans, quota_root, objectid);
3281 if (ret)
3282 goto out;
3283
3284 /*
3285 * add qgroup to all inherited groups
3286 */
3287 if (inherit) {
3288 i_qgroups = (u64 *)(inherit + 1);
3289 for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
3290 if (*i_qgroups == 0)
3291 continue;
3292 ret = add_qgroup_relation_item(trans, objectid,
3293 *i_qgroups);
3294 if (ret && ret != -EEXIST)
3295 goto out;
3296 ret = add_qgroup_relation_item(trans, *i_qgroups,
3297 objectid);
3298 if (ret && ret != -EEXIST)
3299 goto out;
3300 }
3301 ret = 0;
3302
3303 qlist_prealloc = kcalloc(inherit->num_qgroups,
3304 sizeof(struct btrfs_qgroup_list *),
3305 GFP_NOFS);
3306 if (!qlist_prealloc) {
3307 ret = -ENOMEM;
3308 goto out;
3309 }
3310 for (int i = 0; i < inherit->num_qgroups; i++) {
3311 qlist_prealloc[i] = kzalloc(sizeof(struct btrfs_qgroup_list),
3312 GFP_NOFS);
3313 if (!qlist_prealloc[i]) {
3314 ret = -ENOMEM;
3315 goto out;
3316 }
3317 }
3318 }
3319
3320 spin_lock(&fs_info->qgroup_lock);
3321
3322 dstgroup = add_qgroup_rb(fs_info, prealloc, objectid);
3323 prealloc = NULL;
3324
3325 if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
3326 dstgroup->lim_flags = inherit->lim.flags;
3327 dstgroup->max_rfer = inherit->lim.max_rfer;
3328 dstgroup->max_excl = inherit->lim.max_excl;
3329 dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
3330 dstgroup->rsv_excl = inherit->lim.rsv_excl;
3331
3332 qgroup_dirty(fs_info, dstgroup);
3333 }
3334
3335 if (srcid && btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL) {
3336 srcgroup = find_qgroup_rb(fs_info, srcid);
3337 if (!srcgroup)
3338 goto unlock;
3339
3340 /*
3341 * We call inherit after we clone the root in order to make sure
3342 * our counts don't go crazy, so at this point the only
3343 * difference between the two roots should be the root node.
3344 */
3345 level_size = fs_info->nodesize;
3346 dstgroup->rfer = srcgroup->rfer;
3347 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
3348 dstgroup->excl = level_size;
3349 dstgroup->excl_cmpr = level_size;
3350 srcgroup->excl = level_size;
3351 srcgroup->excl_cmpr = level_size;
3352
3353 /* inherit the limit info */
3354 dstgroup->lim_flags = srcgroup->lim_flags;
3355 dstgroup->max_rfer = srcgroup->max_rfer;
3356 dstgroup->max_excl = srcgroup->max_excl;
3357 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
3358 dstgroup->rsv_excl = srcgroup->rsv_excl;
3359
3360 qgroup_dirty(fs_info, dstgroup);
3361 qgroup_dirty(fs_info, srcgroup);
3362
3363 /*
3364 * If the source qgroup has parent but the new one doesn't,
3365 * we need a full rescan.
3366 */
3367 if (!inherit && !list_empty(&srcgroup->groups))
3368 need_rescan = true;
3369 }
3370
3371 if (!inherit)
3372 goto unlock;
3373
3374 i_qgroups = (u64 *)(inherit + 1);
3375 for (i = 0; i < inherit->num_qgroups; ++i) {
3376 if (*i_qgroups) {
3377 ret = add_relation_rb(fs_info, qlist_prealloc[i], objectid,
3378 *i_qgroups);
3379 qlist_prealloc[i] = NULL;
3380 if (ret)
3381 goto unlock;
3382 }
3383 if (srcid) {
3384 /* Check if we can do a quick inherit. */
3385 ret = qgroup_snapshot_quick_inherit(fs_info, srcid, *i_qgroups);
3386 if (ret < 0)
3387 goto unlock;
3388 if (ret > 0)
3389 need_rescan = true;
3390 ret = 0;
3391 }
3392 ++i_qgroups;
3393 }
3394
3395 for (i = 0; i < inherit->num_ref_copies; ++i, i_qgroups += 2) {
3396 struct btrfs_qgroup *src;
3397 struct btrfs_qgroup *dst;
3398
3399 if (!i_qgroups[0] || !i_qgroups[1])
3400 continue;
3401
3402 src = find_qgroup_rb(fs_info, i_qgroups[0]);
3403 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3404
3405 if (!src || !dst) {
3406 ret = -EINVAL;
3407 goto unlock;
3408 }
3409
3410 dst->rfer = src->rfer - level_size;
3411 dst->rfer_cmpr = src->rfer_cmpr - level_size;
3412
3413 /* Manually tweaking numbers certainly needs a rescan */
3414 need_rescan = true;
3415 }
3416 for (i = 0; i < inherit->num_excl_copies; ++i, i_qgroups += 2) {
3417 struct btrfs_qgroup *src;
3418 struct btrfs_qgroup *dst;
3419
3420 if (!i_qgroups[0] || !i_qgroups[1])
3421 continue;
3422
3423 src = find_qgroup_rb(fs_info, i_qgroups[0]);
3424 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3425
3426 if (!src || !dst) {
3427 ret = -EINVAL;
3428 goto unlock;
3429 }
3430
3431 dst->excl = src->excl + level_size;
3432 dst->excl_cmpr = src->excl_cmpr + level_size;
3433 need_rescan = true;
3434 }
3435
3436unlock:
3437 spin_unlock(&fs_info->qgroup_lock);
3438 if (!ret)
3439 ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup);
3440out:
3441 if (!committing)
3442 mutex_unlock(&fs_info->qgroup_ioctl_lock);
3443 if (need_rescan)
3444 qgroup_mark_inconsistent(fs_info);
3445 if (qlist_prealloc) {
3446 for (int i = 0; i < inherit->num_qgroups; i++)
3447 kfree(qlist_prealloc[i]);
3448 kfree(qlist_prealloc);
3449 }
3450 if (free_inherit)
3451 kfree(inherit);
3452 kfree(prealloc);
3453 return ret;
3454}
3455
3456static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes)
3457{
3458 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
3459 qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
3460 return false;
3461
3462 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
3463 qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
3464 return false;
3465
3466 return true;
3467}
3468
3469static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
3470 enum btrfs_qgroup_rsv_type type)
3471{
3472 struct btrfs_qgroup *qgroup;
3473 struct btrfs_fs_info *fs_info = root->fs_info;
3474 u64 ref_root = root->root_key.objectid;
3475 int ret = 0;
3476 LIST_HEAD(qgroup_list);
3477
3478 if (!is_fstree(ref_root))
3479 return 0;
3480
3481 if (num_bytes == 0)
3482 return 0;
3483
3484 if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
3485 capable(CAP_SYS_RESOURCE))
3486 enforce = false;
3487
3488 spin_lock(&fs_info->qgroup_lock);
3489 if (!fs_info->quota_root)
3490 goto out;
3491
3492 qgroup = find_qgroup_rb(fs_info, ref_root);
3493 if (!qgroup)
3494 goto out;
3495
3496 qgroup_iterator_add(&qgroup_list, qgroup);
3497 list_for_each_entry(qgroup, &qgroup_list, iterator) {
3498 struct btrfs_qgroup_list *glist;
3499
3500 if (enforce && !qgroup_check_limits(qgroup, num_bytes)) {
3501 ret = -EDQUOT;
3502 goto out;
3503 }
3504
3505 list_for_each_entry(glist, &qgroup->groups, next_group)
3506 qgroup_iterator_add(&qgroup_list, glist->group);
3507 }
3508
3509 ret = 0;
3510 /*
3511 * no limits exceeded, now record the reservation into all qgroups
3512 */
3513 list_for_each_entry(qgroup, &qgroup_list, iterator)
3514 qgroup_rsv_add(fs_info, qgroup, num_bytes, type);
3515
3516out:
3517 qgroup_iterator_clean(&qgroup_list);
3518 spin_unlock(&fs_info->qgroup_lock);
3519 return ret;
3520}
3521
3522/*
3523 * Free @num_bytes of reserved space with @type for qgroup. (Normally level 0
3524 * qgroup).
3525 *
3526 * Will handle all higher level qgroup too.
3527 *
3528 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
3529 * This special case is only used for META_PERTRANS type.
3530 */
3531void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
3532 u64 ref_root, u64 num_bytes,
3533 enum btrfs_qgroup_rsv_type type)
3534{
3535 struct btrfs_qgroup *qgroup;
3536 LIST_HEAD(qgroup_list);
3537
3538 if (!is_fstree(ref_root))
3539 return;
3540
3541 if (num_bytes == 0)
3542 return;
3543
3544 if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
3545 WARN(1, "%s: Invalid type to free", __func__);
3546 return;
3547 }
3548 spin_lock(&fs_info->qgroup_lock);
3549
3550 if (!fs_info->quota_root)
3551 goto out;
3552
3553 qgroup = find_qgroup_rb(fs_info, ref_root);
3554 if (!qgroup)
3555 goto out;
3556
3557 if (num_bytes == (u64)-1)
3558 /*
3559 * We're freeing all pertrans rsv, get reserved value from
3560 * level 0 qgroup as real num_bytes to free.
3561 */
3562 num_bytes = qgroup->rsv.values[type];
3563
3564 qgroup_iterator_add(&qgroup_list, qgroup);
3565 list_for_each_entry(qgroup, &qgroup_list, iterator) {
3566 struct btrfs_qgroup_list *glist;
3567
3568 qgroup_rsv_release(fs_info, qgroup, num_bytes, type);
3569 list_for_each_entry(glist, &qgroup->groups, next_group) {
3570 qgroup_iterator_add(&qgroup_list, glist->group);
3571 }
3572 }
3573out:
3574 qgroup_iterator_clean(&qgroup_list);
3575 spin_unlock(&fs_info->qgroup_lock);
3576}
3577
3578/*
3579 * Check if the leaf is the last leaf. Which means all node pointers
3580 * are at their last position.
3581 */
3582static bool is_last_leaf(struct btrfs_path *path)
3583{
3584 int i;
3585
3586 for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3587 if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3588 return false;
3589 }
3590 return true;
3591}
3592
3593/*
3594 * returns < 0 on error, 0 when more leafs are to be scanned.
3595 * returns 1 when done.
3596 */
3597static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3598 struct btrfs_path *path)
3599{
3600 struct btrfs_fs_info *fs_info = trans->fs_info;
3601 struct btrfs_root *extent_root;
3602 struct btrfs_key found;
3603 struct extent_buffer *scratch_leaf = NULL;
3604 u64 num_bytes;
3605 bool done;
3606 int slot;
3607 int ret;
3608
3609 if (!btrfs_qgroup_full_accounting(fs_info))
3610 return 1;
3611
3612 mutex_lock(&fs_info->qgroup_rescan_lock);
3613 extent_root = btrfs_extent_root(fs_info,
3614 fs_info->qgroup_rescan_progress.objectid);
3615 ret = btrfs_search_slot_for_read(extent_root,
3616 &fs_info->qgroup_rescan_progress,
3617 path, 1, 0);
3618
3619 btrfs_debug(fs_info,
3620 "current progress key (%llu %u %llu), search_slot ret %d",
3621 fs_info->qgroup_rescan_progress.objectid,
3622 fs_info->qgroup_rescan_progress.type,
3623 fs_info->qgroup_rescan_progress.offset, ret);
3624
3625 if (ret) {
3626 /*
3627 * The rescan is about to end, we will not be scanning any
3628 * further blocks. We cannot unset the RESCAN flag here, because
3629 * we want to commit the transaction if everything went well.
3630 * To make the live accounting work in this phase, we set our
3631 * scan progress pointer such that every real extent objectid
3632 * will be smaller.
3633 */
3634 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3635 btrfs_release_path(path);
3636 mutex_unlock(&fs_info->qgroup_rescan_lock);
3637 return ret;
3638 }
3639 done = is_last_leaf(path);
3640
3641 btrfs_item_key_to_cpu(path->nodes[0], &found,
3642 btrfs_header_nritems(path->nodes[0]) - 1);
3643 fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3644
3645 scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3646 if (!scratch_leaf) {
3647 ret = -ENOMEM;
3648 mutex_unlock(&fs_info->qgroup_rescan_lock);
3649 goto out;
3650 }
3651 slot = path->slots[0];
3652 btrfs_release_path(path);
3653 mutex_unlock(&fs_info->qgroup_rescan_lock);
3654
3655 for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3656 struct btrfs_backref_walk_ctx ctx = { 0 };
3657
3658 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3659 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3660 found.type != BTRFS_METADATA_ITEM_KEY)
3661 continue;
3662 if (found.type == BTRFS_METADATA_ITEM_KEY)
3663 num_bytes = fs_info->nodesize;
3664 else
3665 num_bytes = found.offset;
3666
3667 ctx.bytenr = found.objectid;
3668 ctx.fs_info = fs_info;
3669
3670 ret = btrfs_find_all_roots(&ctx, false);
3671 if (ret < 0)
3672 goto out;
3673 /* For rescan, just pass old_roots as NULL */
3674 ret = btrfs_qgroup_account_extent(trans, found.objectid,
3675 num_bytes, NULL, ctx.roots);
3676 if (ret < 0)
3677 goto out;
3678 }
3679out:
3680 if (scratch_leaf)
3681 free_extent_buffer(scratch_leaf);
3682
3683 if (done && !ret) {
3684 ret = 1;
3685 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3686 }
3687 return ret;
3688}
3689
3690static bool rescan_should_stop(struct btrfs_fs_info *fs_info)
3691{
3692 if (btrfs_fs_closing(fs_info))
3693 return true;
3694 if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
3695 return true;
3696 if (!btrfs_qgroup_enabled(fs_info))
3697 return true;
3698 if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3699 return true;
3700 return false;
3701}
3702
3703static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3704{
3705 struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3706 qgroup_rescan_work);
3707 struct btrfs_path *path;
3708 struct btrfs_trans_handle *trans = NULL;
3709 int err = -ENOMEM;
3710 int ret = 0;
3711 bool stopped = false;
3712 bool did_leaf_rescans = false;
3713
3714 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
3715 return;
3716
3717 path = btrfs_alloc_path();
3718 if (!path)
3719 goto out;
3720 /*
3721 * Rescan should only search for commit root, and any later difference
3722 * should be recorded by qgroup
3723 */
3724 path->search_commit_root = 1;
3725 path->skip_locking = 1;
3726
3727 err = 0;
3728 while (!err && !(stopped = rescan_should_stop(fs_info))) {
3729 trans = btrfs_start_transaction(fs_info->fs_root, 0);
3730 if (IS_ERR(trans)) {
3731 err = PTR_ERR(trans);
3732 break;
3733 }
3734
3735 err = qgroup_rescan_leaf(trans, path);
3736 did_leaf_rescans = true;
3737
3738 if (err > 0)
3739 btrfs_commit_transaction(trans);
3740 else
3741 btrfs_end_transaction(trans);
3742 }
3743
3744out:
3745 btrfs_free_path(path);
3746
3747 mutex_lock(&fs_info->qgroup_rescan_lock);
3748 if (err > 0 &&
3749 fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3750 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3751 } else if (err < 0 || stopped) {
3752 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3753 }
3754 mutex_unlock(&fs_info->qgroup_rescan_lock);
3755
3756 /*
3757 * Only update status, since the previous part has already updated the
3758 * qgroup info, and only if we did any actual work. This also prevents
3759 * race with a concurrent quota disable, which has already set
3760 * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at
3761 * btrfs_quota_disable().
3762 */
3763 if (did_leaf_rescans) {
3764 trans = btrfs_start_transaction(fs_info->quota_root, 1);
3765 if (IS_ERR(trans)) {
3766 err = PTR_ERR(trans);
3767 trans = NULL;
3768 btrfs_err(fs_info,
3769 "fail to start transaction for status update: %d",
3770 err);
3771 }
3772 } else {
3773 trans = NULL;
3774 }
3775
3776 mutex_lock(&fs_info->qgroup_rescan_lock);
3777 if (!stopped ||
3778 fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3779 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3780 if (trans) {
3781 ret = update_qgroup_status_item(trans);
3782 if (ret < 0) {
3783 err = ret;
3784 btrfs_err(fs_info, "fail to update qgroup status: %d",
3785 err);
3786 }
3787 }
3788 fs_info->qgroup_rescan_running = false;
3789 fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3790 complete_all(&fs_info->qgroup_rescan_completion);
3791 mutex_unlock(&fs_info->qgroup_rescan_lock);
3792
3793 if (!trans)
3794 return;
3795
3796 btrfs_end_transaction(trans);
3797
3798 if (stopped) {
3799 btrfs_info(fs_info, "qgroup scan paused");
3800 } else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) {
3801 btrfs_info(fs_info, "qgroup scan cancelled");
3802 } else if (err >= 0) {
3803 btrfs_info(fs_info, "qgroup scan completed%s",
3804 err > 0 ? " (inconsistency flag cleared)" : "");
3805 } else {
3806 btrfs_err(fs_info, "qgroup scan failed with %d", err);
3807 }
3808}
3809
3810/*
3811 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3812 * memory required for the rescan context.
3813 */
3814static int
3815qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3816 int init_flags)
3817{
3818 int ret = 0;
3819
3820 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) {
3821 btrfs_warn(fs_info, "qgroup rescan init failed, running in simple mode");
3822 return -EINVAL;
3823 }
3824
3825 if (!init_flags) {
3826 /* we're resuming qgroup rescan at mount time */
3827 if (!(fs_info->qgroup_flags &
3828 BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3829 btrfs_warn(fs_info,
3830 "qgroup rescan init failed, qgroup rescan is not queued");
3831 ret = -EINVAL;
3832 } else if (!(fs_info->qgroup_flags &
3833 BTRFS_QGROUP_STATUS_FLAG_ON)) {
3834 btrfs_warn(fs_info,
3835 "qgroup rescan init failed, qgroup is not enabled");
3836 ret = -EINVAL;
3837 }
3838
3839 if (ret)
3840 return ret;
3841 }
3842
3843 mutex_lock(&fs_info->qgroup_rescan_lock);
3844
3845 if (init_flags) {
3846 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3847 btrfs_warn(fs_info,
3848 "qgroup rescan is already in progress");
3849 ret = -EINPROGRESS;
3850 } else if (!(fs_info->qgroup_flags &
3851 BTRFS_QGROUP_STATUS_FLAG_ON)) {
3852 btrfs_warn(fs_info,
3853 "qgroup rescan init failed, qgroup is not enabled");
3854 ret = -EINVAL;
3855 } else if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
3856 /* Quota disable is in progress */
3857 ret = -EBUSY;
3858 }
3859
3860 if (ret) {
3861 mutex_unlock(&fs_info->qgroup_rescan_lock);
3862 return ret;
3863 }
3864 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3865 }
3866
3867 memset(&fs_info->qgroup_rescan_progress, 0,
3868 sizeof(fs_info->qgroup_rescan_progress));
3869 fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
3870 BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
3871 fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3872 init_completion(&fs_info->qgroup_rescan_completion);
3873 mutex_unlock(&fs_info->qgroup_rescan_lock);
3874
3875 btrfs_init_work(&fs_info->qgroup_rescan_work,
3876 btrfs_qgroup_rescan_worker, NULL);
3877 return 0;
3878}
3879
3880static void
3881qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3882{
3883 struct rb_node *n;
3884 struct btrfs_qgroup *qgroup;
3885
3886 spin_lock(&fs_info->qgroup_lock);
3887 /* clear all current qgroup tracking information */
3888 for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3889 qgroup = rb_entry(n, struct btrfs_qgroup, node);
3890 qgroup->rfer = 0;
3891 qgroup->rfer_cmpr = 0;
3892 qgroup->excl = 0;
3893 qgroup->excl_cmpr = 0;
3894 qgroup_dirty(fs_info, qgroup);
3895 }
3896 spin_unlock(&fs_info->qgroup_lock);
3897}
3898
3899int
3900btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3901{
3902 int ret = 0;
3903 struct btrfs_trans_handle *trans;
3904
3905 ret = qgroup_rescan_init(fs_info, 0, 1);
3906 if (ret)
3907 return ret;
3908
3909 /*
3910 * We have set the rescan_progress to 0, which means no more
3911 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3912 * However, btrfs_qgroup_account_ref may be right after its call
3913 * to btrfs_find_all_roots, in which case it would still do the
3914 * accounting.
3915 * To solve this, we're committing the transaction, which will
3916 * ensure we run all delayed refs and only after that, we are
3917 * going to clear all tracking information for a clean start.
3918 */
3919
3920 trans = btrfs_attach_transaction_barrier(fs_info->fs_root);
3921 if (IS_ERR(trans) && trans != ERR_PTR(-ENOENT)) {
3922 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3923 return PTR_ERR(trans);
3924 } else if (trans != ERR_PTR(-ENOENT)) {
3925 ret = btrfs_commit_transaction(trans);
3926 if (ret) {
3927 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3928 return ret;
3929 }
3930 }
3931
3932 qgroup_rescan_zero_tracking(fs_info);
3933
3934 mutex_lock(&fs_info->qgroup_rescan_lock);
3935 fs_info->qgroup_rescan_running = true;
3936 btrfs_queue_work(fs_info->qgroup_rescan_workers,
3937 &fs_info->qgroup_rescan_work);
3938 mutex_unlock(&fs_info->qgroup_rescan_lock);
3939
3940 return 0;
3941}
3942
3943int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3944 bool interruptible)
3945{
3946 int running;
3947 int ret = 0;
3948
3949 mutex_lock(&fs_info->qgroup_rescan_lock);
3950 running = fs_info->qgroup_rescan_running;
3951 mutex_unlock(&fs_info->qgroup_rescan_lock);
3952
3953 if (!running)
3954 return 0;
3955
3956 if (interruptible)
3957 ret = wait_for_completion_interruptible(
3958 &fs_info->qgroup_rescan_completion);
3959 else
3960 wait_for_completion(&fs_info->qgroup_rescan_completion);
3961
3962 return ret;
3963}
3964
3965/*
3966 * this is only called from open_ctree where we're still single threaded, thus
3967 * locking is omitted here.
3968 */
3969void
3970btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3971{
3972 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3973 mutex_lock(&fs_info->qgroup_rescan_lock);
3974 fs_info->qgroup_rescan_running = true;
3975 btrfs_queue_work(fs_info->qgroup_rescan_workers,
3976 &fs_info->qgroup_rescan_work);
3977 mutex_unlock(&fs_info->qgroup_rescan_lock);
3978 }
3979}
3980
3981#define rbtree_iterate_from_safe(node, next, start) \
3982 for (node = start; node && ({ next = rb_next(node); 1;}); node = next)
3983
3984static int qgroup_unreserve_range(struct btrfs_inode *inode,
3985 struct extent_changeset *reserved, u64 start,
3986 u64 len)
3987{
3988 struct rb_node *node;
3989 struct rb_node *next;
3990 struct ulist_node *entry;
3991 int ret = 0;
3992
3993 node = reserved->range_changed.root.rb_node;
3994 if (!node)
3995 return 0;
3996 while (node) {
3997 entry = rb_entry(node, struct ulist_node, rb_node);
3998 if (entry->val < start)
3999 node = node->rb_right;
4000 else
4001 node = node->rb_left;
4002 }
4003
4004 if (entry->val > start && rb_prev(&entry->rb_node))
4005 entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
4006 rb_node);
4007
4008 rbtree_iterate_from_safe(node, next, &entry->rb_node) {
4009 u64 entry_start;
4010 u64 entry_end;
4011 u64 entry_len;
4012 int clear_ret;
4013
4014 entry = rb_entry(node, struct ulist_node, rb_node);
4015 entry_start = entry->val;
4016 entry_end = entry->aux;
4017 entry_len = entry_end - entry_start + 1;
4018
4019 if (entry_start >= start + len)
4020 break;
4021 if (entry_start + entry_len <= start)
4022 continue;
4023 /*
4024 * Now the entry is in [start, start + len), revert the
4025 * EXTENT_QGROUP_RESERVED bit.
4026 */
4027 clear_ret = clear_extent_bits(&inode->io_tree, entry_start,
4028 entry_end, EXTENT_QGROUP_RESERVED);
4029 if (!ret && clear_ret < 0)
4030 ret = clear_ret;
4031
4032 ulist_del(&reserved->range_changed, entry->val, entry->aux);
4033 if (likely(reserved->bytes_changed >= entry_len)) {
4034 reserved->bytes_changed -= entry_len;
4035 } else {
4036 WARN_ON(1);
4037 reserved->bytes_changed = 0;
4038 }
4039 }
4040
4041 return ret;
4042}
4043
4044/*
4045 * Try to free some space for qgroup.
4046 *
4047 * For qgroup, there are only 3 ways to free qgroup space:
4048 * - Flush nodatacow write
4049 * Any nodatacow write will free its reserved data space at run_delalloc_range().
4050 * In theory, we should only flush nodatacow inodes, but it's not yet
4051 * possible, so we need to flush the whole root.
4052 *
4053 * - Wait for ordered extents
4054 * When ordered extents are finished, their reserved metadata is finally
4055 * converted to per_trans status, which can be freed by later commit
4056 * transaction.
4057 *
4058 * - Commit transaction
4059 * This would free the meta_per_trans space.
4060 * In theory this shouldn't provide much space, but any more qgroup space
4061 * is needed.
4062 */
4063static int try_flush_qgroup(struct btrfs_root *root)
4064{
4065 struct btrfs_trans_handle *trans;
4066 int ret;
4067
4068 /* Can't hold an open transaction or we run the risk of deadlocking. */
4069 ASSERT(current->journal_info == NULL);
4070 if (WARN_ON(current->journal_info))
4071 return 0;
4072
4073 /*
4074 * We don't want to run flush again and again, so if there is a running
4075 * one, we won't try to start a new flush, but exit directly.
4076 */
4077 if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) {
4078 wait_event(root->qgroup_flush_wait,
4079 !test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state));
4080 return 0;
4081 }
4082
4083 ret = btrfs_start_delalloc_snapshot(root, true);
4084 if (ret < 0)
4085 goto out;
4086 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
4087
4088 trans = btrfs_attach_transaction_barrier(root);
4089 if (IS_ERR(trans)) {
4090 ret = PTR_ERR(trans);
4091 if (ret == -ENOENT)
4092 ret = 0;
4093 goto out;
4094 }
4095
4096 ret = btrfs_commit_transaction(trans);
4097out:
4098 clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state);
4099 wake_up(&root->qgroup_flush_wait);
4100 return ret;
4101}
4102
4103static int qgroup_reserve_data(struct btrfs_inode *inode,
4104 struct extent_changeset **reserved_ret, u64 start,
4105 u64 len)
4106{
4107 struct btrfs_root *root = inode->root;
4108 struct extent_changeset *reserved;
4109 bool new_reserved = false;
4110 u64 orig_reserved;
4111 u64 to_reserve;
4112 int ret;
4113
4114 if (btrfs_qgroup_mode(root->fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4115 !is_fstree(root->root_key.objectid) || len == 0)
4116 return 0;
4117
4118 /* @reserved parameter is mandatory for qgroup */
4119 if (WARN_ON(!reserved_ret))
4120 return -EINVAL;
4121 if (!*reserved_ret) {
4122 new_reserved = true;
4123 *reserved_ret = extent_changeset_alloc();
4124 if (!*reserved_ret)
4125 return -ENOMEM;
4126 }
4127 reserved = *reserved_ret;
4128 /* Record already reserved space */
4129 orig_reserved = reserved->bytes_changed;
4130 ret = set_record_extent_bits(&inode->io_tree, start,
4131 start + len -1, EXTENT_QGROUP_RESERVED, reserved);
4132
4133 /* Newly reserved space */
4134 to_reserve = reserved->bytes_changed - orig_reserved;
4135 trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len,
4136 to_reserve, QGROUP_RESERVE);
4137 if (ret < 0)
4138 goto out;
4139 ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
4140 if (ret < 0)
4141 goto cleanup;
4142
4143 return ret;
4144
4145cleanup:
4146 qgroup_unreserve_range(inode, reserved, start, len);
4147out:
4148 if (new_reserved) {
4149 extent_changeset_free(reserved);
4150 *reserved_ret = NULL;
4151 }
4152 return ret;
4153}
4154
4155/*
4156 * Reserve qgroup space for range [start, start + len).
4157 *
4158 * This function will either reserve space from related qgroups or do nothing
4159 * if the range is already reserved.
4160 *
4161 * Return 0 for successful reservation
4162 * Return <0 for error (including -EQUOT)
4163 *
4164 * NOTE: This function may sleep for memory allocation, dirty page flushing and
4165 * commit transaction. So caller should not hold any dirty page locked.
4166 */
4167int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
4168 struct extent_changeset **reserved_ret, u64 start,
4169 u64 len)
4170{
4171 int ret;
4172
4173 ret = qgroup_reserve_data(inode, reserved_ret, start, len);
4174 if (ret <= 0 && ret != -EDQUOT)
4175 return ret;
4176
4177 ret = try_flush_qgroup(inode->root);
4178 if (ret < 0)
4179 return ret;
4180 return qgroup_reserve_data(inode, reserved_ret, start, len);
4181}
4182
4183/* Free ranges specified by @reserved, normally in error path */
4184static int qgroup_free_reserved_data(struct btrfs_inode *inode,
4185 struct extent_changeset *reserved,
4186 u64 start, u64 len, u64 *freed_ret)
4187{
4188 struct btrfs_root *root = inode->root;
4189 struct ulist_node *unode;
4190 struct ulist_iterator uiter;
4191 struct extent_changeset changeset;
4192 u64 freed = 0;
4193 int ret;
4194
4195 extent_changeset_init(&changeset);
4196 len = round_up(start + len, root->fs_info->sectorsize);
4197 start = round_down(start, root->fs_info->sectorsize);
4198
4199 ULIST_ITER_INIT(&uiter);
4200 while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
4201 u64 range_start = unode->val;
4202 /* unode->aux is the inclusive end */
4203 u64 range_len = unode->aux - range_start + 1;
4204 u64 free_start;
4205 u64 free_len;
4206
4207 extent_changeset_release(&changeset);
4208
4209 /* Only free range in range [start, start + len) */
4210 if (range_start >= start + len ||
4211 range_start + range_len <= start)
4212 continue;
4213 free_start = max(range_start, start);
4214 free_len = min(start + len, range_start + range_len) -
4215 free_start;
4216 /*
4217 * TODO: To also modify reserved->ranges_reserved to reflect
4218 * the modification.
4219 *
4220 * However as long as we free qgroup reserved according to
4221 * EXTENT_QGROUP_RESERVED, we won't double free.
4222 * So not need to rush.
4223 */
4224 ret = clear_record_extent_bits(&inode->io_tree, free_start,
4225 free_start + free_len - 1,
4226 EXTENT_QGROUP_RESERVED, &changeset);
4227 if (ret < 0)
4228 goto out;
4229 freed += changeset.bytes_changed;
4230 }
4231 btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
4232 BTRFS_QGROUP_RSV_DATA);
4233 if (freed_ret)
4234 *freed_ret = freed;
4235 ret = 0;
4236out:
4237 extent_changeset_release(&changeset);
4238 return ret;
4239}
4240
4241static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
4242 struct extent_changeset *reserved, u64 start, u64 len,
4243 u64 *released, int free)
4244{
4245 struct extent_changeset changeset;
4246 int trace_op = QGROUP_RELEASE;
4247 int ret;
4248
4249 if (btrfs_qgroup_mode(inode->root->fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
4250 extent_changeset_init(&changeset);
4251 return clear_record_extent_bits(&inode->io_tree, start,
4252 start + len - 1,
4253 EXTENT_QGROUP_RESERVED, &changeset);
4254 }
4255
4256 /* In release case, we shouldn't have @reserved */
4257 WARN_ON(!free && reserved);
4258 if (free && reserved)
4259 return qgroup_free_reserved_data(inode, reserved, start, len, released);
4260 extent_changeset_init(&changeset);
4261 ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
4262 EXTENT_QGROUP_RESERVED, &changeset);
4263 if (ret < 0)
4264 goto out;
4265
4266 if (free)
4267 trace_op = QGROUP_FREE;
4268 trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len,
4269 changeset.bytes_changed, trace_op);
4270 if (free)
4271 btrfs_qgroup_free_refroot(inode->root->fs_info,
4272 inode->root->root_key.objectid,
4273 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4274 if (released)
4275 *released = changeset.bytes_changed;
4276out:
4277 extent_changeset_release(&changeset);
4278 return ret;
4279}
4280
4281/*
4282 * Free a reserved space range from io_tree and related qgroups
4283 *
4284 * Should be called when a range of pages get invalidated before reaching disk.
4285 * Or for error cleanup case.
4286 * if @reserved is given, only reserved range in [@start, @start + @len) will
4287 * be freed.
4288 *
4289 * For data written to disk, use btrfs_qgroup_release_data().
4290 *
4291 * NOTE: This function may sleep for memory allocation.
4292 */
4293int btrfs_qgroup_free_data(struct btrfs_inode *inode,
4294 struct extent_changeset *reserved,
4295 u64 start, u64 len, u64 *freed)
4296{
4297 return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1);
4298}
4299
4300/*
4301 * Release a reserved space range from io_tree only.
4302 *
4303 * Should be called when a range of pages get written to disk and corresponding
4304 * FILE_EXTENT is inserted into corresponding root.
4305 *
4306 * Since new qgroup accounting framework will only update qgroup numbers at
4307 * commit_transaction() time, its reserved space shouldn't be freed from
4308 * related qgroups.
4309 *
4310 * But we should release the range from io_tree, to allow further write to be
4311 * COWed.
4312 *
4313 * NOTE: This function may sleep for memory allocation.
4314 */
4315int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released)
4316{
4317 return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0);
4318}
4319
4320static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4321 enum btrfs_qgroup_rsv_type type)
4322{
4323 if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4324 type != BTRFS_QGROUP_RSV_META_PERTRANS)
4325 return;
4326 if (num_bytes == 0)
4327 return;
4328
4329 spin_lock(&root->qgroup_meta_rsv_lock);
4330 if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
4331 root->qgroup_meta_rsv_prealloc += num_bytes;
4332 else
4333 root->qgroup_meta_rsv_pertrans += num_bytes;
4334 spin_unlock(&root->qgroup_meta_rsv_lock);
4335}
4336
4337static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4338 enum btrfs_qgroup_rsv_type type)
4339{
4340 if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4341 type != BTRFS_QGROUP_RSV_META_PERTRANS)
4342 return 0;
4343 if (num_bytes == 0)
4344 return 0;
4345
4346 spin_lock(&root->qgroup_meta_rsv_lock);
4347 if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
4348 num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
4349 num_bytes);
4350 root->qgroup_meta_rsv_prealloc -= num_bytes;
4351 } else {
4352 num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
4353 num_bytes);
4354 root->qgroup_meta_rsv_pertrans -= num_bytes;
4355 }
4356 spin_unlock(&root->qgroup_meta_rsv_lock);
4357 return num_bytes;
4358}
4359
4360int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4361 enum btrfs_qgroup_rsv_type type, bool enforce)
4362{
4363 struct btrfs_fs_info *fs_info = root->fs_info;
4364 int ret;
4365
4366 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4367 !is_fstree(root->root_key.objectid) || num_bytes == 0)
4368 return 0;
4369
4370 BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4371 trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
4372 ret = qgroup_reserve(root, num_bytes, enforce, type);
4373 if (ret < 0)
4374 return ret;
4375 /*
4376 * Record what we have reserved into root.
4377 *
4378 * To avoid quota disabled->enabled underflow.
4379 * In that case, we may try to free space we haven't reserved
4380 * (since quota was disabled), so record what we reserved into root.
4381 * And ensure later release won't underflow this number.
4382 */
4383 add_root_meta_rsv(root, num_bytes, type);
4384 return ret;
4385}
4386
4387int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4388 enum btrfs_qgroup_rsv_type type, bool enforce,
4389 bool noflush)
4390{
4391 int ret;
4392
4393 ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4394 if ((ret <= 0 && ret != -EDQUOT) || noflush)
4395 return ret;
4396
4397 ret = try_flush_qgroup(root);
4398 if (ret < 0)
4399 return ret;
4400 return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4401}
4402
4403/*
4404 * Per-transaction meta reservation should be all freed at transaction commit
4405 * time
4406 */
4407void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
4408{
4409 struct btrfs_fs_info *fs_info = root->fs_info;
4410
4411 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4412 !is_fstree(root->root_key.objectid))
4413 return;
4414
4415 /* TODO: Update trace point to handle such free */
4416 trace_qgroup_meta_free_all_pertrans(root);
4417 /* Special value -1 means to free all reserved space */
4418 btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
4419 BTRFS_QGROUP_RSV_META_PERTRANS);
4420}
4421
4422void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
4423 enum btrfs_qgroup_rsv_type type)
4424{
4425 struct btrfs_fs_info *fs_info = root->fs_info;
4426
4427 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4428 !is_fstree(root->root_key.objectid))
4429 return;
4430
4431 /*
4432 * reservation for META_PREALLOC can happen before quota is enabled,
4433 * which can lead to underflow.
4434 * Here ensure we will only free what we really have reserved.
4435 */
4436 num_bytes = sub_root_meta_rsv(root, num_bytes, type);
4437 BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4438 trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
4439 btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
4440 num_bytes, type);
4441}
4442
4443static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
4444 int num_bytes)
4445{
4446 struct btrfs_qgroup *qgroup;
4447 LIST_HEAD(qgroup_list);
4448
4449 if (num_bytes == 0)
4450 return;
4451 if (!fs_info->quota_root)
4452 return;
4453
4454 spin_lock(&fs_info->qgroup_lock);
4455 qgroup = find_qgroup_rb(fs_info, ref_root);
4456 if (!qgroup)
4457 goto out;
4458
4459 qgroup_iterator_add(&qgroup_list, qgroup);
4460 list_for_each_entry(qgroup, &qgroup_list, iterator) {
4461 struct btrfs_qgroup_list *glist;
4462
4463 qgroup_rsv_release(fs_info, qgroup, num_bytes,
4464 BTRFS_QGROUP_RSV_META_PREALLOC);
4465 if (!sb_rdonly(fs_info->sb))
4466 qgroup_rsv_add(fs_info, qgroup, num_bytes,
4467 BTRFS_QGROUP_RSV_META_PERTRANS);
4468
4469 list_for_each_entry(glist, &qgroup->groups, next_group)
4470 qgroup_iterator_add(&qgroup_list, glist->group);
4471 }
4472out:
4473 qgroup_iterator_clean(&qgroup_list);
4474 spin_unlock(&fs_info->qgroup_lock);
4475}
4476
4477/*
4478 * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS.
4479 *
4480 * This is called when preallocated meta reservation needs to be used.
4481 * Normally after btrfs_join_transaction() call.
4482 */
4483void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
4484{
4485 struct btrfs_fs_info *fs_info = root->fs_info;
4486
4487 if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4488 !is_fstree(root->root_key.objectid))
4489 return;
4490 /* Same as btrfs_qgroup_free_meta_prealloc() */
4491 num_bytes = sub_root_meta_rsv(root, num_bytes,
4492 BTRFS_QGROUP_RSV_META_PREALLOC);
4493 trace_qgroup_meta_convert(root, num_bytes);
4494 qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
4495 if (!sb_rdonly(fs_info->sb))
4496 add_root_meta_rsv(root, num_bytes, BTRFS_QGROUP_RSV_META_PERTRANS);
4497}
4498
4499/*
4500 * Check qgroup reserved space leaking, normally at destroy inode
4501 * time
4502 */
4503void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode)
4504{
4505 struct extent_changeset changeset;
4506 struct ulist_node *unode;
4507 struct ulist_iterator iter;
4508 int ret;
4509
4510 extent_changeset_init(&changeset);
4511 ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1,
4512 EXTENT_QGROUP_RESERVED, &changeset);
4513
4514 WARN_ON(ret < 0);
4515 if (WARN_ON(changeset.bytes_changed)) {
4516 ULIST_ITER_INIT(&iter);
4517 while ((unode = ulist_next(&changeset.range_changed, &iter))) {
4518 btrfs_warn(inode->root->fs_info,
4519 "leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu",
4520 btrfs_ino(inode), unode->val, unode->aux);
4521 }
4522 btrfs_qgroup_free_refroot(inode->root->fs_info,
4523 inode->root->root_key.objectid,
4524 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4525
4526 }
4527 extent_changeset_release(&changeset);
4528}
4529
4530void btrfs_qgroup_init_swapped_blocks(
4531 struct btrfs_qgroup_swapped_blocks *swapped_blocks)
4532{
4533 int i;
4534
4535 spin_lock_init(&swapped_blocks->lock);
4536 for (i = 0; i < BTRFS_MAX_LEVEL; i++)
4537 swapped_blocks->blocks[i] = RB_ROOT;
4538 swapped_blocks->swapped = false;
4539}
4540
4541/*
4542 * Delete all swapped blocks record of @root.
4543 * Every record here means we skipped a full subtree scan for qgroup.
4544 *
4545 * Gets called when committing one transaction.
4546 */
4547void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
4548{
4549 struct btrfs_qgroup_swapped_blocks *swapped_blocks;
4550 int i;
4551
4552 swapped_blocks = &root->swapped_blocks;
4553
4554 spin_lock(&swapped_blocks->lock);
4555 if (!swapped_blocks->swapped)
4556 goto out;
4557 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4558 struct rb_root *cur_root = &swapped_blocks->blocks[i];
4559 struct btrfs_qgroup_swapped_block *entry;
4560 struct btrfs_qgroup_swapped_block *next;
4561
4562 rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
4563 node)
4564 kfree(entry);
4565 swapped_blocks->blocks[i] = RB_ROOT;
4566 }
4567 swapped_blocks->swapped = false;
4568out:
4569 spin_unlock(&swapped_blocks->lock);
4570}
4571
4572/*
4573 * Add subtree roots record into @subvol_root.
4574 *
4575 * @subvol_root: tree root of the subvolume tree get swapped
4576 * @bg: block group under balance
4577 * @subvol_parent/slot: pointer to the subtree root in subvolume tree
4578 * @reloc_parent/slot: pointer to the subtree root in reloc tree
4579 * BOTH POINTERS ARE BEFORE TREE SWAP
4580 * @last_snapshot: last snapshot generation of the subvolume tree
4581 */
4582int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
4583 struct btrfs_root *subvol_root,
4584 struct btrfs_block_group *bg,
4585 struct extent_buffer *subvol_parent, int subvol_slot,
4586 struct extent_buffer *reloc_parent, int reloc_slot,
4587 u64 last_snapshot)
4588{
4589 struct btrfs_fs_info *fs_info = subvol_root->fs_info;
4590 struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
4591 struct btrfs_qgroup_swapped_block *block;
4592 struct rb_node **cur;
4593 struct rb_node *parent = NULL;
4594 int level = btrfs_header_level(subvol_parent) - 1;
4595 int ret = 0;
4596
4597 if (!btrfs_qgroup_full_accounting(fs_info))
4598 return 0;
4599
4600 if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
4601 btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
4602 btrfs_err_rl(fs_info,
4603 "%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
4604 __func__,
4605 btrfs_node_ptr_generation(subvol_parent, subvol_slot),
4606 btrfs_node_ptr_generation(reloc_parent, reloc_slot));
4607 return -EUCLEAN;
4608 }
4609
4610 block = kmalloc(sizeof(*block), GFP_NOFS);
4611 if (!block) {
4612 ret = -ENOMEM;
4613 goto out;
4614 }
4615
4616 /*
4617 * @reloc_parent/slot is still before swap, while @block is going to
4618 * record the bytenr after swap, so we do the swap here.
4619 */
4620 block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
4621 block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
4622 reloc_slot);
4623 block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
4624 block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
4625 subvol_slot);
4626 block->last_snapshot = last_snapshot;
4627 block->level = level;
4628
4629 /*
4630 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
4631 * no one else can modify tree blocks thus we qgroup will not change
4632 * no matter the value of trace_leaf.
4633 */
4634 if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
4635 block->trace_leaf = true;
4636 else
4637 block->trace_leaf = false;
4638 btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
4639
4640 /* Insert @block into @blocks */
4641 spin_lock(&blocks->lock);
4642 cur = &blocks->blocks[level].rb_node;
4643 while (*cur) {
4644 struct btrfs_qgroup_swapped_block *entry;
4645
4646 parent = *cur;
4647 entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
4648 node);
4649
4650 if (entry->subvol_bytenr < block->subvol_bytenr) {
4651 cur = &(*cur)->rb_left;
4652 } else if (entry->subvol_bytenr > block->subvol_bytenr) {
4653 cur = &(*cur)->rb_right;
4654 } else {
4655 if (entry->subvol_generation !=
4656 block->subvol_generation ||
4657 entry->reloc_bytenr != block->reloc_bytenr ||
4658 entry->reloc_generation !=
4659 block->reloc_generation) {
4660 /*
4661 * Duplicated but mismatch entry found.
4662 * Shouldn't happen.
4663 *
4664 * Marking qgroup inconsistent should be enough
4665 * for end users.
4666 */
4667 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4668 ret = -EEXIST;
4669 }
4670 kfree(block);
4671 goto out_unlock;
4672 }
4673 }
4674 rb_link_node(&block->node, parent, cur);
4675 rb_insert_color(&block->node, &blocks->blocks[level]);
4676 blocks->swapped = true;
4677out_unlock:
4678 spin_unlock(&blocks->lock);
4679out:
4680 if (ret < 0)
4681 qgroup_mark_inconsistent(fs_info);
4682 return ret;
4683}
4684
4685/*
4686 * Check if the tree block is a subtree root, and if so do the needed
4687 * delayed subtree trace for qgroup.
4688 *
4689 * This is called during btrfs_cow_block().
4690 */
4691int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
4692 struct btrfs_root *root,
4693 struct extent_buffer *subvol_eb)
4694{
4695 struct btrfs_fs_info *fs_info = root->fs_info;
4696 struct btrfs_tree_parent_check check = { 0 };
4697 struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
4698 struct btrfs_qgroup_swapped_block *block;
4699 struct extent_buffer *reloc_eb = NULL;
4700 struct rb_node *node;
4701 bool found = false;
4702 bool swapped = false;
4703 int level = btrfs_header_level(subvol_eb);
4704 int ret = 0;
4705 int i;
4706
4707 if (!btrfs_qgroup_full_accounting(fs_info))
4708 return 0;
4709 if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
4710 return 0;
4711
4712 spin_lock(&blocks->lock);
4713 if (!blocks->swapped) {
4714 spin_unlock(&blocks->lock);
4715 return 0;
4716 }
4717 node = blocks->blocks[level].rb_node;
4718
4719 while (node) {
4720 block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
4721 if (block->subvol_bytenr < subvol_eb->start) {
4722 node = node->rb_left;
4723 } else if (block->subvol_bytenr > subvol_eb->start) {
4724 node = node->rb_right;
4725 } else {
4726 found = true;
4727 break;
4728 }
4729 }
4730 if (!found) {
4731 spin_unlock(&blocks->lock);
4732 goto out;
4733 }
4734 /* Found one, remove it from @blocks first and update blocks->swapped */
4735 rb_erase(&block->node, &blocks->blocks[level]);
4736 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4737 if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
4738 swapped = true;
4739 break;
4740 }
4741 }
4742 blocks->swapped = swapped;
4743 spin_unlock(&blocks->lock);
4744
4745 check.level = block->level;
4746 check.transid = block->reloc_generation;
4747 check.has_first_key = true;
4748 memcpy(&check.first_key, &block->first_key, sizeof(check.first_key));
4749
4750 /* Read out reloc subtree root */
4751 reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check);
4752 if (IS_ERR(reloc_eb)) {
4753 ret = PTR_ERR(reloc_eb);
4754 reloc_eb = NULL;
4755 goto free_out;
4756 }
4757 if (!extent_buffer_uptodate(reloc_eb)) {
4758 ret = -EIO;
4759 goto free_out;
4760 }
4761
4762 ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4763 block->last_snapshot, block->trace_leaf);
4764free_out:
4765 kfree(block);
4766 free_extent_buffer(reloc_eb);
4767out:
4768 if (ret < 0) {
4769 btrfs_err_rl(fs_info,
4770 "failed to account subtree at bytenr %llu: %d",
4771 subvol_eb->start, ret);
4772 qgroup_mark_inconsistent(fs_info);
4773 }
4774 return ret;
4775}
4776
4777void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
4778{
4779 struct btrfs_qgroup_extent_record *entry;
4780 struct btrfs_qgroup_extent_record *next;
4781 struct rb_root *root;
4782
4783 root = &trans->delayed_refs.dirty_extent_root;
4784 rbtree_postorder_for_each_entry_safe(entry, next, root, node) {
4785 ulist_free(entry->old_roots);
4786 kfree(entry);
4787 }
4788 *root = RB_ROOT;
4789}
4790
4791void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes)
4792{
4793 if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4794 return;
4795
4796 if (!is_fstree(root))
4797 return;
4798
4799 btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA);
4800}
4801
4802int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
4803 struct btrfs_squota_delta *delta)
4804{
4805 int ret;
4806 struct btrfs_qgroup *qgroup;
4807 struct btrfs_qgroup *qg;
4808 LIST_HEAD(qgroup_list);
4809 u64 root = delta->root;
4810 u64 num_bytes = delta->num_bytes;
4811 const int sign = (delta->is_inc ? 1 : -1);
4812
4813 if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4814 return 0;
4815
4816 if (!is_fstree(root))
4817 return 0;
4818
4819 /* If the extent predates enabling quotas, don't count it. */
4820 if (delta->generation < fs_info->qgroup_enable_gen)
4821 return 0;
4822
4823 spin_lock(&fs_info->qgroup_lock);
4824 qgroup = find_qgroup_rb(fs_info, root);
4825 if (!qgroup) {
4826 ret = -ENOENT;
4827 goto out;
4828 }
4829
4830 ret = 0;
4831 qgroup_iterator_add(&qgroup_list, qgroup);
4832 list_for_each_entry(qg, &qgroup_list, iterator) {
4833 struct btrfs_qgroup_list *glist;
4834
4835 qg->excl += num_bytes * sign;
4836 qg->rfer += num_bytes * sign;
4837 qgroup_dirty(fs_info, qg);
4838
4839 list_for_each_entry(glist, &qg->groups, next_group)
4840 qgroup_iterator_add(&qgroup_list, glist->group);
4841 }
4842 qgroup_iterator_clean(&qgroup_list);
4843
4844out:
4845 spin_unlock(&fs_info->qgroup_lock);
4846 return ret;
4847}