1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/sched.h>
7 #include <linux/sched/signal.h>
8 #include <linux/pagemap.h>
9 #include <linux/writeback.h>
10 #include <linux/blkdev.h>
11 #include <linux/sort.h>
12 #include <linux/rcupdate.h>
13 #include <linux/kthread.h>
14 #include <linux/slab.h>
15 #include <linux/ratelimit.h>
16 #include <linux/percpu_counter.h>
17 #include <linux/lockdep.h>
18 #include <linux/crc32c.h>
19 #include "misc.h"
20 #include "tree-log.h"
21 #include "disk-io.h"
22 #include "print-tree.h"
23 #include "volumes.h"
24 #include "raid56.h"
25 #include "locking.h"
26 #include "free-space-cache.h"
27 #include "free-space-tree.h"
28 #include "sysfs.h"
29 #include "qgroup.h"
30 #include "ref-verify.h"
31 #include "space-info.h"
32 #include "block-rsv.h"
33 #include "delalloc-space.h"
34 #include "block-group.h"
35 #include "discard.h"
36 #include "rcu-string.h"
37 #include "zoned.h"
38 #include "dev-replace.h"
39
40 #undef SCRAMBLE_DELAYED_REFS
41
42
43 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
44 struct btrfs_delayed_ref_node *node, u64 parent,
45 u64 root_objectid, u64 owner_objectid,
46 u64 owner_offset, int refs_to_drop,
47 struct btrfs_delayed_extent_op *extra_op);
48 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
49 struct extent_buffer *leaf,
50 struct btrfs_extent_item *ei);
51 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
52 u64 parent, u64 root_objectid,
53 u64 flags, u64 owner, u64 offset,
54 struct btrfs_key *ins, int ref_mod);
55 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
56 struct btrfs_delayed_ref_node *node,
57 struct btrfs_delayed_extent_op *extent_op);
58 static int find_next_key(struct btrfs_path *path, int level,
59 struct btrfs_key *key);
60
block_group_bits(struct btrfs_block_group * cache,u64 bits)61 static int block_group_bits(struct btrfs_block_group *cache, u64 bits)
62 {
63 return (cache->flags & bits) == bits;
64 }
65
btrfs_add_excluded_extent(struct btrfs_fs_info * fs_info,u64 start,u64 num_bytes)66 int btrfs_add_excluded_extent(struct btrfs_fs_info *fs_info,
67 u64 start, u64 num_bytes)
68 {
69 u64 end = start + num_bytes - 1;
70 set_extent_bits(&fs_info->excluded_extents, start, end,
71 EXTENT_UPTODATE);
72 return 0;
73 }
74
btrfs_free_excluded_extents(struct btrfs_block_group * cache)75 void btrfs_free_excluded_extents(struct btrfs_block_group *cache)
76 {
77 struct btrfs_fs_info *fs_info = cache->fs_info;
78 u64 start, end;
79
80 start = cache->start;
81 end = start + cache->length - 1;
82
83 clear_extent_bits(&fs_info->excluded_extents, start, end,
84 EXTENT_UPTODATE);
85 }
86
87 /* simple helper to search for an existing data extent at a given offset */
btrfs_lookup_data_extent(struct btrfs_fs_info * fs_info,u64 start,u64 len)88 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
89 {
90 struct btrfs_root *root = btrfs_extent_root(fs_info, start);
91 int ret;
92 struct btrfs_key key;
93 struct btrfs_path *path;
94
95 path = btrfs_alloc_path();
96 if (!path)
97 return -ENOMEM;
98
99 key.objectid = start;
100 key.offset = len;
101 key.type = BTRFS_EXTENT_ITEM_KEY;
102 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
103 btrfs_free_path(path);
104 return ret;
105 }
106
107 /*
108 * helper function to lookup reference count and flags of a tree block.
109 *
110 * the head node for delayed ref is used to store the sum of all the
111 * reference count modifications queued up in the rbtree. the head
112 * node may also store the extent flags to set. This way you can check
113 * to see what the reference count and extent flags would be if all of
114 * the delayed refs are not processed.
115 */
btrfs_lookup_extent_info(struct btrfs_trans_handle * trans,struct btrfs_fs_info * fs_info,u64 bytenr,u64 offset,int metadata,u64 * refs,u64 * flags)116 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
117 struct btrfs_fs_info *fs_info, u64 bytenr,
118 u64 offset, int metadata, u64 *refs, u64 *flags)
119 {
120 struct btrfs_root *extent_root;
121 struct btrfs_delayed_ref_head *head;
122 struct btrfs_delayed_ref_root *delayed_refs;
123 struct btrfs_path *path;
124 struct btrfs_extent_item *ei;
125 struct extent_buffer *leaf;
126 struct btrfs_key key;
127 u32 item_size;
128 u64 num_refs;
129 u64 extent_flags;
130 int ret;
131
132 /*
133 * If we don't have skinny metadata, don't bother doing anything
134 * different
135 */
136 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
137 offset = fs_info->nodesize;
138 metadata = 0;
139 }
140
141 path = btrfs_alloc_path();
142 if (!path)
143 return -ENOMEM;
144
145 if (!trans) {
146 path->skip_locking = 1;
147 path->search_commit_root = 1;
148 }
149
150 search_again:
151 key.objectid = bytenr;
152 key.offset = offset;
153 if (metadata)
154 key.type = BTRFS_METADATA_ITEM_KEY;
155 else
156 key.type = BTRFS_EXTENT_ITEM_KEY;
157
158 extent_root = btrfs_extent_root(fs_info, bytenr);
159 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
160 if (ret < 0)
161 goto out_free;
162
163 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
164 if (path->slots[0]) {
165 path->slots[0]--;
166 btrfs_item_key_to_cpu(path->nodes[0], &key,
167 path->slots[0]);
168 if (key.objectid == bytenr &&
169 key.type == BTRFS_EXTENT_ITEM_KEY &&
170 key.offset == fs_info->nodesize)
171 ret = 0;
172 }
173 }
174
175 if (ret == 0) {
176 leaf = path->nodes[0];
177 item_size = btrfs_item_size(leaf, path->slots[0]);
178 if (item_size >= sizeof(*ei)) {
179 ei = btrfs_item_ptr(leaf, path->slots[0],
180 struct btrfs_extent_item);
181 num_refs = btrfs_extent_refs(leaf, ei);
182 extent_flags = btrfs_extent_flags(leaf, ei);
183 } else {
184 ret = -EINVAL;
185 btrfs_print_v0_err(fs_info);
186 if (trans)
187 btrfs_abort_transaction(trans, ret);
188 else
189 btrfs_handle_fs_error(fs_info, ret, NULL);
190
191 goto out_free;
192 }
193
194 BUG_ON(num_refs == 0);
195 } else {
196 num_refs = 0;
197 extent_flags = 0;
198 ret = 0;
199 }
200
201 if (!trans)
202 goto out;
203
204 delayed_refs = &trans->transaction->delayed_refs;
205 spin_lock(&delayed_refs->lock);
206 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
207 if (head) {
208 if (!mutex_trylock(&head->mutex)) {
209 refcount_inc(&head->refs);
210 spin_unlock(&delayed_refs->lock);
211
212 btrfs_release_path(path);
213
214 /*
215 * Mutex was contended, block until it's released and try
216 * again
217 */
218 mutex_lock(&head->mutex);
219 mutex_unlock(&head->mutex);
220 btrfs_put_delayed_ref_head(head);
221 goto search_again;
222 }
223 spin_lock(&head->lock);
224 if (head->extent_op && head->extent_op->update_flags)
225 extent_flags |= head->extent_op->flags_to_set;
226 else
227 BUG_ON(num_refs == 0);
228
229 num_refs += head->ref_mod;
230 spin_unlock(&head->lock);
231 mutex_unlock(&head->mutex);
232 }
233 spin_unlock(&delayed_refs->lock);
234 out:
235 WARN_ON(num_refs == 0);
236 if (refs)
237 *refs = num_refs;
238 if (flags)
239 *flags = extent_flags;
240 out_free:
241 btrfs_free_path(path);
242 return ret;
243 }
244
245 /*
246 * Back reference rules. Back refs have three main goals:
247 *
248 * 1) differentiate between all holders of references to an extent so that
249 * when a reference is dropped we can make sure it was a valid reference
250 * before freeing the extent.
251 *
252 * 2) Provide enough information to quickly find the holders of an extent
253 * if we notice a given block is corrupted or bad.
254 *
255 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
256 * maintenance. This is actually the same as #2, but with a slightly
257 * different use case.
258 *
259 * There are two kinds of back refs. The implicit back refs is optimized
260 * for pointers in non-shared tree blocks. For a given pointer in a block,
261 * back refs of this kind provide information about the block's owner tree
262 * and the pointer's key. These information allow us to find the block by
263 * b-tree searching. The full back refs is for pointers in tree blocks not
264 * referenced by their owner trees. The location of tree block is recorded
265 * in the back refs. Actually the full back refs is generic, and can be
266 * used in all cases the implicit back refs is used. The major shortcoming
267 * of the full back refs is its overhead. Every time a tree block gets
268 * COWed, we have to update back refs entry for all pointers in it.
269 *
270 * For a newly allocated tree block, we use implicit back refs for
271 * pointers in it. This means most tree related operations only involve
272 * implicit back refs. For a tree block created in old transaction, the
273 * only way to drop a reference to it is COW it. So we can detect the
274 * event that tree block loses its owner tree's reference and do the
275 * back refs conversion.
276 *
277 * When a tree block is COWed through a tree, there are four cases:
278 *
279 * The reference count of the block is one and the tree is the block's
280 * owner tree. Nothing to do in this case.
281 *
282 * The reference count of the block is one and the tree is not the
283 * block's owner tree. In this case, full back refs is used for pointers
284 * in the block. Remove these full back refs, add implicit back refs for
285 * every pointers in the new block.
286 *
287 * The reference count of the block is greater than one and the tree is
288 * the block's owner tree. In this case, implicit back refs is used for
289 * pointers in the block. Add full back refs for every pointers in the
290 * block, increase lower level extents' reference counts. The original
291 * implicit back refs are entailed to the new block.
292 *
293 * The reference count of the block is greater than one and the tree is
294 * not the block's owner tree. Add implicit back refs for every pointer in
295 * the new block, increase lower level extents' reference count.
296 *
297 * Back Reference Key composing:
298 *
299 * The key objectid corresponds to the first byte in the extent,
300 * The key type is used to differentiate between types of back refs.
301 * There are different meanings of the key offset for different types
302 * of back refs.
303 *
304 * File extents can be referenced by:
305 *
306 * - multiple snapshots, subvolumes, or different generations in one subvol
307 * - different files inside a single subvolume
308 * - different offsets inside a file (bookend extents in file.c)
309 *
310 * The extent ref structure for the implicit back refs has fields for:
311 *
312 * - Objectid of the subvolume root
313 * - objectid of the file holding the reference
314 * - original offset in the file
315 * - how many bookend extents
316 *
317 * The key offset for the implicit back refs is hash of the first
318 * three fields.
319 *
320 * The extent ref structure for the full back refs has field for:
321 *
322 * - number of pointers in the tree leaf
323 *
324 * The key offset for the implicit back refs is the first byte of
325 * the tree leaf
326 *
327 * When a file extent is allocated, The implicit back refs is used.
328 * the fields are filled in:
329 *
330 * (root_key.objectid, inode objectid, offset in file, 1)
331 *
332 * When a file extent is removed file truncation, we find the
333 * corresponding implicit back refs and check the following fields:
334 *
335 * (btrfs_header_owner(leaf), inode objectid, offset in file)
336 *
337 * Btree extents can be referenced by:
338 *
339 * - Different subvolumes
340 *
341 * Both the implicit back refs and the full back refs for tree blocks
342 * only consist of key. The key offset for the implicit back refs is
343 * objectid of block's owner tree. The key offset for the full back refs
344 * is the first byte of parent block.
345 *
346 * When implicit back refs is used, information about the lowest key and
347 * level of the tree block are required. These information are stored in
348 * tree block info structure.
349 */
350
351 /*
352 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
353 * is_data == BTRFS_REF_TYPE_DATA, data type is requiried,
354 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
355 */
btrfs_get_extent_inline_ref_type(const struct extent_buffer * eb,struct btrfs_extent_inline_ref * iref,enum btrfs_inline_ref_type is_data)356 int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
357 struct btrfs_extent_inline_ref *iref,
358 enum btrfs_inline_ref_type is_data)
359 {
360 int type = btrfs_extent_inline_ref_type(eb, iref);
361 u64 offset = btrfs_extent_inline_ref_offset(eb, iref);
362
363 if (type == BTRFS_TREE_BLOCK_REF_KEY ||
364 type == BTRFS_SHARED_BLOCK_REF_KEY ||
365 type == BTRFS_SHARED_DATA_REF_KEY ||
366 type == BTRFS_EXTENT_DATA_REF_KEY) {
367 if (is_data == BTRFS_REF_TYPE_BLOCK) {
368 if (type == BTRFS_TREE_BLOCK_REF_KEY)
369 return type;
370 if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
371 ASSERT(eb->fs_info);
372 /*
373 * Every shared one has parent tree block,
374 * which must be aligned to sector size.
375 */
376 if (offset &&
377 IS_ALIGNED(offset, eb->fs_info->sectorsize))
378 return type;
379 }
380 } else if (is_data == BTRFS_REF_TYPE_DATA) {
381 if (type == BTRFS_EXTENT_DATA_REF_KEY)
382 return type;
383 if (type == BTRFS_SHARED_DATA_REF_KEY) {
384 ASSERT(eb->fs_info);
385 /*
386 * Every shared one has parent tree block,
387 * which must be aligned to sector size.
388 */
389 if (offset &&
390 IS_ALIGNED(offset, eb->fs_info->sectorsize))
391 return type;
392 }
393 } else {
394 ASSERT(is_data == BTRFS_REF_TYPE_ANY);
395 return type;
396 }
397 }
398
399 btrfs_print_leaf((struct extent_buffer *)eb);
400 btrfs_err(eb->fs_info,
401 "eb %llu iref 0x%lx invalid extent inline ref type %d",
402 eb->start, (unsigned long)iref, type);
403 WARN_ON(1);
404
405 return BTRFS_REF_TYPE_INVALID;
406 }
407
hash_extent_data_ref(u64 root_objectid,u64 owner,u64 offset)408 u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
409 {
410 u32 high_crc = ~(u32)0;
411 u32 low_crc = ~(u32)0;
412 __le64 lenum;
413
414 lenum = cpu_to_le64(root_objectid);
415 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
416 lenum = cpu_to_le64(owner);
417 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
418 lenum = cpu_to_le64(offset);
419 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
420
421 return ((u64)high_crc << 31) ^ (u64)low_crc;
422 }
423
hash_extent_data_ref_item(struct extent_buffer * leaf,struct btrfs_extent_data_ref * ref)424 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
425 struct btrfs_extent_data_ref *ref)
426 {
427 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
428 btrfs_extent_data_ref_objectid(leaf, ref),
429 btrfs_extent_data_ref_offset(leaf, ref));
430 }
431
match_extent_data_ref(struct extent_buffer * leaf,struct btrfs_extent_data_ref * ref,u64 root_objectid,u64 owner,u64 offset)432 static int match_extent_data_ref(struct extent_buffer *leaf,
433 struct btrfs_extent_data_ref *ref,
434 u64 root_objectid, u64 owner, u64 offset)
435 {
436 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
437 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
438 btrfs_extent_data_ref_offset(leaf, ref) != offset)
439 return 0;
440 return 1;
441 }
442
lookup_extent_data_ref(struct btrfs_trans_handle * trans,struct btrfs_path * path,u64 bytenr,u64 parent,u64 root_objectid,u64 owner,u64 offset)443 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
444 struct btrfs_path *path,
445 u64 bytenr, u64 parent,
446 u64 root_objectid,
447 u64 owner, u64 offset)
448 {
449 struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr);
450 struct btrfs_key key;
451 struct btrfs_extent_data_ref *ref;
452 struct extent_buffer *leaf;
453 u32 nritems;
454 int ret;
455 int recow;
456 int err = -ENOENT;
457
458 key.objectid = bytenr;
459 if (parent) {
460 key.type = BTRFS_SHARED_DATA_REF_KEY;
461 key.offset = parent;
462 } else {
463 key.type = BTRFS_EXTENT_DATA_REF_KEY;
464 key.offset = hash_extent_data_ref(root_objectid,
465 owner, offset);
466 }
467 again:
468 recow = 0;
469 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
470 if (ret < 0) {
471 err = ret;
472 goto fail;
473 }
474
475 if (parent) {
476 if (!ret)
477 return 0;
478 goto fail;
479 }
480
481 leaf = path->nodes[0];
482 nritems = btrfs_header_nritems(leaf);
483 while (1) {
484 if (path->slots[0] >= nritems) {
485 ret = btrfs_next_leaf(root, path);
486 if (ret < 0)
487 err = ret;
488 if (ret)
489 goto fail;
490
491 leaf = path->nodes[0];
492 nritems = btrfs_header_nritems(leaf);
493 recow = 1;
494 }
495
496 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
497 if (key.objectid != bytenr ||
498 key.type != BTRFS_EXTENT_DATA_REF_KEY)
499 goto fail;
500
501 ref = btrfs_item_ptr(leaf, path->slots[0],
502 struct btrfs_extent_data_ref);
503
504 if (match_extent_data_ref(leaf, ref, root_objectid,
505 owner, offset)) {
506 if (recow) {
507 btrfs_release_path(path);
508 goto again;
509 }
510 err = 0;
511 break;
512 }
513 path->slots[0]++;
514 }
515 fail:
516 return err;
517 }
518
insert_extent_data_ref(struct btrfs_trans_handle * trans,struct btrfs_path * path,u64 bytenr,u64 parent,u64 root_objectid,u64 owner,u64 offset,int refs_to_add)519 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
520 struct btrfs_path *path,
521 u64 bytenr, u64 parent,
522 u64 root_objectid, u64 owner,
523 u64 offset, int refs_to_add)
524 {
525 struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr);
526 struct btrfs_key key;
527 struct extent_buffer *leaf;
528 u32 size;
529 u32 num_refs;
530 int ret;
531
532 key.objectid = bytenr;
533 if (parent) {
534 key.type = BTRFS_SHARED_DATA_REF_KEY;
535 key.offset = parent;
536 size = sizeof(struct btrfs_shared_data_ref);
537 } else {
538 key.type = BTRFS_EXTENT_DATA_REF_KEY;
539 key.offset = hash_extent_data_ref(root_objectid,
540 owner, offset);
541 size = sizeof(struct btrfs_extent_data_ref);
542 }
543
544 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
545 if (ret && ret != -EEXIST)
546 goto fail;
547
548 leaf = path->nodes[0];
549 if (parent) {
550 struct btrfs_shared_data_ref *ref;
551 ref = btrfs_item_ptr(leaf, path->slots[0],
552 struct btrfs_shared_data_ref);
553 if (ret == 0) {
554 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
555 } else {
556 num_refs = btrfs_shared_data_ref_count(leaf, ref);
557 num_refs += refs_to_add;
558 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
559 }
560 } else {
561 struct btrfs_extent_data_ref *ref;
562 while (ret == -EEXIST) {
563 ref = btrfs_item_ptr(leaf, path->slots[0],
564 struct btrfs_extent_data_ref);
565 if (match_extent_data_ref(leaf, ref, root_objectid,
566 owner, offset))
567 break;
568 btrfs_release_path(path);
569 key.offset++;
570 ret = btrfs_insert_empty_item(trans, root, path, &key,
571 size);
572 if (ret && ret != -EEXIST)
573 goto fail;
574
575 leaf = path->nodes[0];
576 }
577 ref = btrfs_item_ptr(leaf, path->slots[0],
578 struct btrfs_extent_data_ref);
579 if (ret == 0) {
580 btrfs_set_extent_data_ref_root(leaf, ref,
581 root_objectid);
582 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
583 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
584 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
585 } else {
586 num_refs = btrfs_extent_data_ref_count(leaf, ref);
587 num_refs += refs_to_add;
588 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
589 }
590 }
591 btrfs_mark_buffer_dirty(leaf);
592 ret = 0;
593 fail:
594 btrfs_release_path(path);
595 return ret;
596 }
597
remove_extent_data_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,int refs_to_drop)598 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
599 struct btrfs_root *root,
600 struct btrfs_path *path,
601 int refs_to_drop)
602 {
603 struct btrfs_key key;
604 struct btrfs_extent_data_ref *ref1 = NULL;
605 struct btrfs_shared_data_ref *ref2 = NULL;
606 struct extent_buffer *leaf;
607 u32 num_refs = 0;
608 int ret = 0;
609
610 leaf = path->nodes[0];
611 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
612
613 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
614 ref1 = btrfs_item_ptr(leaf, path->slots[0],
615 struct btrfs_extent_data_ref);
616 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
617 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
618 ref2 = btrfs_item_ptr(leaf, path->slots[0],
619 struct btrfs_shared_data_ref);
620 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
621 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
622 btrfs_print_v0_err(trans->fs_info);
623 btrfs_abort_transaction(trans, -EINVAL);
624 return -EINVAL;
625 } else {
626 BUG();
627 }
628
629 BUG_ON(num_refs < refs_to_drop);
630 num_refs -= refs_to_drop;
631
632 if (num_refs == 0) {
633 ret = btrfs_del_item(trans, root, path);
634 } else {
635 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
636 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
637 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
638 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
639 btrfs_mark_buffer_dirty(leaf);
640 }
641 return ret;
642 }
643
extent_data_ref_count(struct btrfs_path * path,struct btrfs_extent_inline_ref * iref)644 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
645 struct btrfs_extent_inline_ref *iref)
646 {
647 struct btrfs_key key;
648 struct extent_buffer *leaf;
649 struct btrfs_extent_data_ref *ref1;
650 struct btrfs_shared_data_ref *ref2;
651 u32 num_refs = 0;
652 int type;
653
654 leaf = path->nodes[0];
655 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
656
657 BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
658 if (iref) {
659 /*
660 * If type is invalid, we should have bailed out earlier than
661 * this call.
662 */
663 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
664 ASSERT(type != BTRFS_REF_TYPE_INVALID);
665 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
666 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
667 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
668 } else {
669 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
670 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
671 }
672 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
673 ref1 = btrfs_item_ptr(leaf, path->slots[0],
674 struct btrfs_extent_data_ref);
675 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
676 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
677 ref2 = btrfs_item_ptr(leaf, path->slots[0],
678 struct btrfs_shared_data_ref);
679 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
680 } else {
681 WARN_ON(1);
682 }
683 return num_refs;
684 }
685
lookup_tree_block_ref(struct btrfs_trans_handle * trans,struct btrfs_path * path,u64 bytenr,u64 parent,u64 root_objectid)686 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
687 struct btrfs_path *path,
688 u64 bytenr, u64 parent,
689 u64 root_objectid)
690 {
691 struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr);
692 struct btrfs_key key;
693 int ret;
694
695 key.objectid = bytenr;
696 if (parent) {
697 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
698 key.offset = parent;
699 } else {
700 key.type = BTRFS_TREE_BLOCK_REF_KEY;
701 key.offset = root_objectid;
702 }
703
704 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
705 if (ret > 0)
706 ret = -ENOENT;
707 return ret;
708 }
709
insert_tree_block_ref(struct btrfs_trans_handle * trans,struct btrfs_path * path,u64 bytenr,u64 parent,u64 root_objectid)710 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
711 struct btrfs_path *path,
712 u64 bytenr, u64 parent,
713 u64 root_objectid)
714 {
715 struct btrfs_root *root = btrfs_extent_root(trans->fs_info, bytenr);
716 struct btrfs_key key;
717 int ret;
718
719 key.objectid = bytenr;
720 if (parent) {
721 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
722 key.offset = parent;
723 } else {
724 key.type = BTRFS_TREE_BLOCK_REF_KEY;
725 key.offset = root_objectid;
726 }
727
728 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
729 btrfs_release_path(path);
730 return ret;
731 }
732
extent_ref_type(u64 parent,u64 owner)733 static inline int extent_ref_type(u64 parent, u64 owner)
734 {
735 int type;
736 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
737 if (parent > 0)
738 type = BTRFS_SHARED_BLOCK_REF_KEY;
739 else
740 type = BTRFS_TREE_BLOCK_REF_KEY;
741 } else {
742 if (parent > 0)
743 type = BTRFS_SHARED_DATA_REF_KEY;
744 else
745 type = BTRFS_EXTENT_DATA_REF_KEY;
746 }
747 return type;
748 }
749
find_next_key(struct btrfs_path * path,int level,struct btrfs_key * key)750 static int find_next_key(struct btrfs_path *path, int level,
751 struct btrfs_key *key)
752
753 {
754 for (; level < BTRFS_MAX_LEVEL; level++) {
755 if (!path->nodes[level])
756 break;
757 if (path->slots[level] + 1 >=
758 btrfs_header_nritems(path->nodes[level]))
759 continue;
760 if (level == 0)
761 btrfs_item_key_to_cpu(path->nodes[level], key,
762 path->slots[level] + 1);
763 else
764 btrfs_node_key_to_cpu(path->nodes[level], key,
765 path->slots[level] + 1);
766 return 0;
767 }
768 return 1;
769 }
770
771 /*
772 * look for inline back ref. if back ref is found, *ref_ret is set
773 * to the address of inline back ref, and 0 is returned.
774 *
775 * if back ref isn't found, *ref_ret is set to the address where it
776 * should be inserted, and -ENOENT is returned.
777 *
778 * if insert is true and there are too many inline back refs, the path
779 * points to the extent item, and -EAGAIN is returned.
780 *
781 * NOTE: inline back refs are ordered in the same way that back ref
782 * items in the tree are ordered.
783 */
784 static noinline_for_stack
lookup_inline_extent_backref(struct btrfs_trans_handle * trans,struct btrfs_path * path,struct btrfs_extent_inline_ref ** ref_ret,u64 bytenr,u64 num_bytes,u64 parent,u64 root_objectid,u64 owner,u64 offset,int insert)785 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
786 struct btrfs_path *path,
787 struct btrfs_extent_inline_ref **ref_ret,
788 u64 bytenr, u64 num_bytes,
789 u64 parent, u64 root_objectid,
790 u64 owner, u64 offset, int insert)
791 {
792 struct btrfs_fs_info *fs_info = trans->fs_info;
793 struct btrfs_root *root = btrfs_extent_root(fs_info, bytenr);
794 struct btrfs_key key;
795 struct extent_buffer *leaf;
796 struct btrfs_extent_item *ei;
797 struct btrfs_extent_inline_ref *iref;
798 u64 flags;
799 u64 item_size;
800 unsigned long ptr;
801 unsigned long end;
802 int extra_size;
803 int type;
804 int want;
805 int ret;
806 int err = 0;
807 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
808 int needed;
809
810 key.objectid = bytenr;
811 key.type = BTRFS_EXTENT_ITEM_KEY;
812 key.offset = num_bytes;
813
814 want = extent_ref_type(parent, owner);
815 if (insert) {
816 extra_size = btrfs_extent_inline_ref_size(want);
817 path->search_for_extension = 1;
818 path->keep_locks = 1;
819 } else
820 extra_size = -1;
821
822 /*
823 * Owner is our level, so we can just add one to get the level for the
824 * block we are interested in.
825 */
826 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
827 key.type = BTRFS_METADATA_ITEM_KEY;
828 key.offset = owner;
829 }
830
831 again:
832 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
833 if (ret < 0) {
834 err = ret;
835 goto out;
836 }
837
838 /*
839 * We may be a newly converted file system which still has the old fat
840 * extent entries for metadata, so try and see if we have one of those.
841 */
842 if (ret > 0 && skinny_metadata) {
843 skinny_metadata = false;
844 if (path->slots[0]) {
845 path->slots[0]--;
846 btrfs_item_key_to_cpu(path->nodes[0], &key,
847 path->slots[0]);
848 if (key.objectid == bytenr &&
849 key.type == BTRFS_EXTENT_ITEM_KEY &&
850 key.offset == num_bytes)
851 ret = 0;
852 }
853 if (ret) {
854 key.objectid = bytenr;
855 key.type = BTRFS_EXTENT_ITEM_KEY;
856 key.offset = num_bytes;
857 btrfs_release_path(path);
858 goto again;
859 }
860 }
861
862 if (ret && !insert) {
863 err = -ENOENT;
864 goto out;
865 } else if (WARN_ON(ret)) {
866 err = -EIO;
867 goto out;
868 }
869
870 leaf = path->nodes[0];
871 item_size = btrfs_item_size(leaf, path->slots[0]);
872 if (unlikely(item_size < sizeof(*ei))) {
873 err = -EINVAL;
874 btrfs_print_v0_err(fs_info);
875 btrfs_abort_transaction(trans, err);
876 goto out;
877 }
878
879 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
880 flags = btrfs_extent_flags(leaf, ei);
881
882 ptr = (unsigned long)(ei + 1);
883 end = (unsigned long)ei + item_size;
884
885 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
886 ptr += sizeof(struct btrfs_tree_block_info);
887 BUG_ON(ptr > end);
888 }
889
890 if (owner >= BTRFS_FIRST_FREE_OBJECTID)
891 needed = BTRFS_REF_TYPE_DATA;
892 else
893 needed = BTRFS_REF_TYPE_BLOCK;
894
895 err = -ENOENT;
896 while (1) {
897 if (ptr >= end) {
898 if (ptr > end) {
899 err = -EUCLEAN;
900 btrfs_print_leaf(path->nodes[0]);
901 btrfs_crit(fs_info,
902 "overrun extent record at slot %d while looking for inline extent for root %llu owner %llu offset %llu parent %llu",
903 path->slots[0], root_objectid, owner, offset, parent);
904 }
905 break;
906 }
907 iref = (struct btrfs_extent_inline_ref *)ptr;
908 type = btrfs_get_extent_inline_ref_type(leaf, iref, needed);
909 if (type == BTRFS_REF_TYPE_INVALID) {
910 err = -EUCLEAN;
911 goto out;
912 }
913
914 if (want < type)
915 break;
916 if (want > type) {
917 ptr += btrfs_extent_inline_ref_size(type);
918 continue;
919 }
920
921 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
922 struct btrfs_extent_data_ref *dref;
923 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
924 if (match_extent_data_ref(leaf, dref, root_objectid,
925 owner, offset)) {
926 err = 0;
927 break;
928 }
929 if (hash_extent_data_ref_item(leaf, dref) <
930 hash_extent_data_ref(root_objectid, owner, offset))
931 break;
932 } else {
933 u64 ref_offset;
934 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
935 if (parent > 0) {
936 if (parent == ref_offset) {
937 err = 0;
938 break;
939 }
940 if (ref_offset < parent)
941 break;
942 } else {
943 if (root_objectid == ref_offset) {
944 err = 0;
945 break;
946 }
947 if (ref_offset < root_objectid)
948 break;
949 }
950 }
951 ptr += btrfs_extent_inline_ref_size(type);
952 }
953 if (err == -ENOENT && insert) {
954 if (item_size + extra_size >=
955 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
956 err = -EAGAIN;
957 goto out;
958 }
959 /*
960 * To add new inline back ref, we have to make sure
961 * there is no corresponding back ref item.
962 * For simplicity, we just do not add new inline back
963 * ref if there is any kind of item for this block
964 */
965 if (find_next_key(path, 0, &key) == 0 &&
966 key.objectid == bytenr &&
967 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
968 err = -EAGAIN;
969 goto out;
970 }
971 }
972 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
973 out:
974 if (insert) {
975 path->keep_locks = 0;
976 path->search_for_extension = 0;
977 btrfs_unlock_up_safe(path, 1);
978 }
979 return err;
980 }
981
982 /*
983 * helper to add new inline back ref
984 */
985 static noinline_for_stack
setup_inline_extent_backref(struct btrfs_fs_info * fs_info,struct btrfs_path * path,struct btrfs_extent_inline_ref * iref,u64 parent,u64 root_objectid,u64 owner,u64 offset,int refs_to_add,struct btrfs_delayed_extent_op * extent_op)986 void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
987 struct btrfs_path *path,
988 struct btrfs_extent_inline_ref *iref,
989 u64 parent, u64 root_objectid,
990 u64 owner, u64 offset, int refs_to_add,
991 struct btrfs_delayed_extent_op *extent_op)
992 {
993 struct extent_buffer *leaf;
994 struct btrfs_extent_item *ei;
995 unsigned long ptr;
996 unsigned long end;
997 unsigned long item_offset;
998 u64 refs;
999 int size;
1000 int type;
1001
1002 leaf = path->nodes[0];
1003 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1004 item_offset = (unsigned long)iref - (unsigned long)ei;
1005
1006 type = extent_ref_type(parent, owner);
1007 size = btrfs_extent_inline_ref_size(type);
1008
1009 btrfs_extend_item(path, size);
1010
1011 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1012 refs = btrfs_extent_refs(leaf, ei);
1013 refs += refs_to_add;
1014 btrfs_set_extent_refs(leaf, ei, refs);
1015 if (extent_op)
1016 __run_delayed_extent_op(extent_op, leaf, ei);
1017
1018 ptr = (unsigned long)ei + item_offset;
1019 end = (unsigned long)ei + btrfs_item_size(leaf, path->slots[0]);
1020 if (ptr < end - size)
1021 memmove_extent_buffer(leaf, ptr + size, ptr,
1022 end - size - ptr);
1023
1024 iref = (struct btrfs_extent_inline_ref *)ptr;
1025 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1026 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1027 struct btrfs_extent_data_ref *dref;
1028 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1029 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1030 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1031 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1032 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1033 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1034 struct btrfs_shared_data_ref *sref;
1035 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1036 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1037 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1038 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1039 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1040 } else {
1041 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1042 }
1043 btrfs_mark_buffer_dirty(leaf);
1044 }
1045
lookup_extent_backref(struct btrfs_trans_handle * trans,struct btrfs_path * path,struct btrfs_extent_inline_ref ** ref_ret,u64 bytenr,u64 num_bytes,u64 parent,u64 root_objectid,u64 owner,u64 offset)1046 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1047 struct btrfs_path *path,
1048 struct btrfs_extent_inline_ref **ref_ret,
1049 u64 bytenr, u64 num_bytes, u64 parent,
1050 u64 root_objectid, u64 owner, u64 offset)
1051 {
1052 int ret;
1053
1054 ret = lookup_inline_extent_backref(trans, path, ref_ret, bytenr,
1055 num_bytes, parent, root_objectid,
1056 owner, offset, 0);
1057 if (ret != -ENOENT)
1058 return ret;
1059
1060 btrfs_release_path(path);
1061 *ref_ret = NULL;
1062
1063 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1064 ret = lookup_tree_block_ref(trans, path, bytenr, parent,
1065 root_objectid);
1066 } else {
1067 ret = lookup_extent_data_ref(trans, path, bytenr, parent,
1068 root_objectid, owner, offset);
1069 }
1070 return ret;
1071 }
1072
1073 /*
1074 * helper to update/remove inline back ref
1075 */
1076 static noinline_for_stack
update_inline_extent_backref(struct btrfs_path * path,struct btrfs_extent_inline_ref * iref,int refs_to_mod,struct btrfs_delayed_extent_op * extent_op)1077 void update_inline_extent_backref(struct btrfs_path *path,
1078 struct btrfs_extent_inline_ref *iref,
1079 int refs_to_mod,
1080 struct btrfs_delayed_extent_op *extent_op)
1081 {
1082 struct extent_buffer *leaf = path->nodes[0];
1083 struct btrfs_extent_item *ei;
1084 struct btrfs_extent_data_ref *dref = NULL;
1085 struct btrfs_shared_data_ref *sref = NULL;
1086 unsigned long ptr;
1087 unsigned long end;
1088 u32 item_size;
1089 int size;
1090 int type;
1091 u64 refs;
1092
1093 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1094 refs = btrfs_extent_refs(leaf, ei);
1095 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1096 refs += refs_to_mod;
1097 btrfs_set_extent_refs(leaf, ei, refs);
1098 if (extent_op)
1099 __run_delayed_extent_op(extent_op, leaf, ei);
1100
1101 /*
1102 * If type is invalid, we should have bailed out after
1103 * lookup_inline_extent_backref().
1104 */
1105 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY);
1106 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1107
1108 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1109 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1110 refs = btrfs_extent_data_ref_count(leaf, dref);
1111 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1112 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1113 refs = btrfs_shared_data_ref_count(leaf, sref);
1114 } else {
1115 refs = 1;
1116 BUG_ON(refs_to_mod != -1);
1117 }
1118
1119 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1120 refs += refs_to_mod;
1121
1122 if (refs > 0) {
1123 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1124 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1125 else
1126 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1127 } else {
1128 size = btrfs_extent_inline_ref_size(type);
1129 item_size = btrfs_item_size(leaf, path->slots[0]);
1130 ptr = (unsigned long)iref;
1131 end = (unsigned long)ei + item_size;
1132 if (ptr + size < end)
1133 memmove_extent_buffer(leaf, ptr, ptr + size,
1134 end - ptr - size);
1135 item_size -= size;
1136 btrfs_truncate_item(path, item_size, 1);
1137 }
1138 btrfs_mark_buffer_dirty(leaf);
1139 }
1140
1141 static noinline_for_stack
insert_inline_extent_backref(struct btrfs_trans_handle * trans,struct btrfs_path * path,u64 bytenr,u64 num_bytes,u64 parent,u64 root_objectid,u64 owner,u64 offset,int refs_to_add,struct btrfs_delayed_extent_op * extent_op)1142 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1143 struct btrfs_path *path,
1144 u64 bytenr, u64 num_bytes, u64 parent,
1145 u64 root_objectid, u64 owner,
1146 u64 offset, int refs_to_add,
1147 struct btrfs_delayed_extent_op *extent_op)
1148 {
1149 struct btrfs_extent_inline_ref *iref;
1150 int ret;
1151
1152 ret = lookup_inline_extent_backref(trans, path, &iref, bytenr,
1153 num_bytes, parent, root_objectid,
1154 owner, offset, 1);
1155 if (ret == 0) {
1156 /*
1157 * We're adding refs to a tree block we already own, this
1158 * should not happen at all.
1159 */
1160 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1161 btrfs_crit(trans->fs_info,
1162 "adding refs to an existing tree ref, bytenr %llu num_bytes %llu root_objectid %llu",
1163 bytenr, num_bytes, root_objectid);
1164 if (IS_ENABLED(CONFIG_BTRFS_DEBUG)) {
1165 WARN_ON(1);
1166 btrfs_crit(trans->fs_info,
1167 "path->slots[0]=%d path->nodes[0]:", path->slots[0]);
1168 btrfs_print_leaf(path->nodes[0]);
1169 }
1170 return -EUCLEAN;
1171 }
1172 update_inline_extent_backref(path, iref, refs_to_add, extent_op);
1173 } else if (ret == -ENOENT) {
1174 setup_inline_extent_backref(trans->fs_info, path, iref, parent,
1175 root_objectid, owner, offset,
1176 refs_to_add, extent_op);
1177 ret = 0;
1178 }
1179 return ret;
1180 }
1181
remove_extent_backref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct btrfs_extent_inline_ref * iref,int refs_to_drop,int is_data)1182 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1183 struct btrfs_root *root,
1184 struct btrfs_path *path,
1185 struct btrfs_extent_inline_ref *iref,
1186 int refs_to_drop, int is_data)
1187 {
1188 int ret = 0;
1189
1190 BUG_ON(!is_data && refs_to_drop != 1);
1191 if (iref)
1192 update_inline_extent_backref(path, iref, -refs_to_drop, NULL);
1193 else if (is_data)
1194 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1195 else
1196 ret = btrfs_del_item(trans, root, path);
1197 return ret;
1198 }
1199
btrfs_issue_discard(struct block_device * bdev,u64 start,u64 len,u64 * discarded_bytes)1200 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
1201 u64 *discarded_bytes)
1202 {
1203 int j, ret = 0;
1204 u64 bytes_left, end;
1205 u64 aligned_start = ALIGN(start, 1 << 9);
1206
1207 if (WARN_ON(start != aligned_start)) {
1208 len -= aligned_start - start;
1209 len = round_down(len, 1 << 9);
1210 start = aligned_start;
1211 }
1212
1213 *discarded_bytes = 0;
1214
1215 if (!len)
1216 return 0;
1217
1218 end = start + len;
1219 bytes_left = len;
1220
1221 /* Skip any superblocks on this device. */
1222 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
1223 u64 sb_start = btrfs_sb_offset(j);
1224 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
1225 u64 size = sb_start - start;
1226
1227 if (!in_range(sb_start, start, bytes_left) &&
1228 !in_range(sb_end, start, bytes_left) &&
1229 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
1230 continue;
1231
1232 /*
1233 * Superblock spans beginning of range. Adjust start and
1234 * try again.
1235 */
1236 if (sb_start <= start) {
1237 start += sb_end - start;
1238 if (start > end) {
1239 bytes_left = 0;
1240 break;
1241 }
1242 bytes_left = end - start;
1243 continue;
1244 }
1245
1246 if (size) {
1247 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
1248 GFP_NOFS);
1249 if (!ret)
1250 *discarded_bytes += size;
1251 else if (ret != -EOPNOTSUPP)
1252 return ret;
1253 }
1254
1255 start = sb_end;
1256 if (start > end) {
1257 bytes_left = 0;
1258 break;
1259 }
1260 bytes_left = end - start;
1261 }
1262
1263 if (bytes_left) {
1264 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
1265 GFP_NOFS);
1266 if (!ret)
1267 *discarded_bytes += bytes_left;
1268 }
1269 return ret;
1270 }
1271
do_discard_extent(struct btrfs_discard_stripe * stripe,u64 * bytes)1272 static int do_discard_extent(struct btrfs_discard_stripe *stripe, u64 *bytes)
1273 {
1274 struct btrfs_device *dev = stripe->dev;
1275 struct btrfs_fs_info *fs_info = dev->fs_info;
1276 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
1277 u64 phys = stripe->physical;
1278 u64 len = stripe->length;
1279 u64 discarded = 0;
1280 int ret = 0;
1281
1282 /* Zone reset on a zoned filesystem */
1283 if (btrfs_can_zone_reset(dev, phys, len)) {
1284 u64 src_disc;
1285
1286 ret = btrfs_reset_device_zone(dev, phys, len, &discarded);
1287 if (ret)
1288 goto out;
1289
1290 if (!btrfs_dev_replace_is_ongoing(dev_replace) ||
1291 dev != dev_replace->srcdev)
1292 goto out;
1293
1294 src_disc = discarded;
1295
1296 /* Send to replace target as well */
1297 ret = btrfs_reset_device_zone(dev_replace->tgtdev, phys, len,
1298 &discarded);
1299 discarded += src_disc;
1300 } else if (bdev_max_discard_sectors(stripe->dev->bdev)) {
1301 ret = btrfs_issue_discard(dev->bdev, phys, len, &discarded);
1302 } else {
1303 ret = 0;
1304 *bytes = 0;
1305 }
1306
1307 out:
1308 *bytes = discarded;
1309 return ret;
1310 }
1311
btrfs_discard_extent(struct btrfs_fs_info * fs_info,u64 bytenr,u64 num_bytes,u64 * actual_bytes)1312 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
1313 u64 num_bytes, u64 *actual_bytes)
1314 {
1315 int ret = 0;
1316 u64 discarded_bytes = 0;
1317 u64 end = bytenr + num_bytes;
1318 u64 cur = bytenr;
1319
1320 /*
1321 * Avoid races with device replace and make sure the devices in the
1322 * stripes don't go away while we are discarding.
1323 */
1324 btrfs_bio_counter_inc_blocked(fs_info);
1325 while (cur < end) {
1326 struct btrfs_discard_stripe *stripes;
1327 unsigned int num_stripes;
1328 int i;
1329
1330 num_bytes = end - cur;
1331 stripes = btrfs_map_discard(fs_info, cur, &num_bytes, &num_stripes);
1332 if (IS_ERR(stripes)) {
1333 ret = PTR_ERR(stripes);
1334 if (ret == -EOPNOTSUPP)
1335 ret = 0;
1336 break;
1337 }
1338
1339 for (i = 0; i < num_stripes; i++) {
1340 struct btrfs_discard_stripe *stripe = stripes + i;
1341 u64 bytes;
1342
1343 if (!stripe->dev->bdev) {
1344 ASSERT(btrfs_test_opt(fs_info, DEGRADED));
1345 continue;
1346 }
1347
1348 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE,
1349 &stripe->dev->dev_state))
1350 continue;
1351
1352 ret = do_discard_extent(stripe, &bytes);
1353 if (ret) {
1354 /*
1355 * Keep going if discard is not supported by the
1356 * device.
1357 */
1358 if (ret != -EOPNOTSUPP)
1359 break;
1360 ret = 0;
1361 } else {
1362 discarded_bytes += bytes;
1363 }
1364 }
1365 kfree(stripes);
1366 if (ret)
1367 break;
1368 cur += num_bytes;
1369 }
1370 btrfs_bio_counter_dec(fs_info);
1371 if (actual_bytes)
1372 *actual_bytes = discarded_bytes;
1373 return ret;
1374 }
1375
1376 /* Can return -ENOMEM */
btrfs_inc_extent_ref(struct btrfs_trans_handle * trans,struct btrfs_ref * generic_ref)1377 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1378 struct btrfs_ref *generic_ref)
1379 {
1380 struct btrfs_fs_info *fs_info = trans->fs_info;
1381 int ret;
1382
1383 ASSERT(generic_ref->type != BTRFS_REF_NOT_SET &&
1384 generic_ref->action);
1385 BUG_ON(generic_ref->type == BTRFS_REF_METADATA &&
1386 generic_ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID);
1387
1388 if (generic_ref->type == BTRFS_REF_METADATA)
1389 ret = btrfs_add_delayed_tree_ref(trans, generic_ref, NULL);
1390 else
1391 ret = btrfs_add_delayed_data_ref(trans, generic_ref, 0);
1392
1393 btrfs_ref_tree_mod(fs_info, generic_ref);
1394
1395 return ret;
1396 }
1397
1398 /*
1399 * __btrfs_inc_extent_ref - insert backreference for a given extent
1400 *
1401 * The counterpart is in __btrfs_free_extent(), with examples and more details
1402 * how it works.
1403 *
1404 * @trans: Handle of transaction
1405 *
1406 * @node: The delayed ref node used to get the bytenr/length for
1407 * extent whose references are incremented.
1408 *
1409 * @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/
1410 * BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical
1411 * bytenr of the parent block. Since new extents are always
1412 * created with indirect references, this will only be the case
1413 * when relocating a shared extent. In that case, root_objectid
1414 * will be BTRFS_TREE_RELOC_OBJECTID. Otherwise, parent must
1415 * be 0
1416 *
1417 * @root_objectid: The id of the root where this modification has originated,
1418 * this can be either one of the well-known metadata trees or
1419 * the subvolume id which references this extent.
1420 *
1421 * @owner: For data extents it is the inode number of the owning file.
1422 * For metadata extents this parameter holds the level in the
1423 * tree of the extent.
1424 *
1425 * @offset: For metadata extents the offset is ignored and is currently
1426 * always passed as 0. For data extents it is the fileoffset
1427 * this extent belongs to.
1428 *
1429 * @refs_to_add Number of references to add
1430 *
1431 * @extent_op Pointer to a structure, holding information necessary when
1432 * updating a tree block's flags
1433 *
1434 */
__btrfs_inc_extent_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,u64 parent,u64 root_objectid,u64 owner,u64 offset,int refs_to_add,struct btrfs_delayed_extent_op * extent_op)1435 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1436 struct btrfs_delayed_ref_node *node,
1437 u64 parent, u64 root_objectid,
1438 u64 owner, u64 offset, int refs_to_add,
1439 struct btrfs_delayed_extent_op *extent_op)
1440 {
1441 struct btrfs_path *path;
1442 struct extent_buffer *leaf;
1443 struct btrfs_extent_item *item;
1444 struct btrfs_key key;
1445 u64 bytenr = node->bytenr;
1446 u64 num_bytes = node->num_bytes;
1447 u64 refs;
1448 int ret;
1449
1450 path = btrfs_alloc_path();
1451 if (!path)
1452 return -ENOMEM;
1453
1454 /* this will setup the path even if it fails to insert the back ref */
1455 ret = insert_inline_extent_backref(trans, path, bytenr, num_bytes,
1456 parent, root_objectid, owner,
1457 offset, refs_to_add, extent_op);
1458 if ((ret < 0 && ret != -EAGAIN) || !ret)
1459 goto out;
1460
1461 /*
1462 * Ok we had -EAGAIN which means we didn't have space to insert and
1463 * inline extent ref, so just update the reference count and add a
1464 * normal backref.
1465 */
1466 leaf = path->nodes[0];
1467 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1468 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1469 refs = btrfs_extent_refs(leaf, item);
1470 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1471 if (extent_op)
1472 __run_delayed_extent_op(extent_op, leaf, item);
1473
1474 btrfs_mark_buffer_dirty(leaf);
1475 btrfs_release_path(path);
1476
1477 /* now insert the actual backref */
1478 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1479 BUG_ON(refs_to_add != 1);
1480 ret = insert_tree_block_ref(trans, path, bytenr, parent,
1481 root_objectid);
1482 } else {
1483 ret = insert_extent_data_ref(trans, path, bytenr, parent,
1484 root_objectid, owner, offset,
1485 refs_to_add);
1486 }
1487 if (ret)
1488 btrfs_abort_transaction(trans, ret);
1489 out:
1490 btrfs_free_path(path);
1491 return ret;
1492 }
1493
run_delayed_data_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,struct btrfs_delayed_extent_op * extent_op,int insert_reserved)1494 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1495 struct btrfs_delayed_ref_node *node,
1496 struct btrfs_delayed_extent_op *extent_op,
1497 int insert_reserved)
1498 {
1499 int ret = 0;
1500 struct btrfs_delayed_data_ref *ref;
1501 struct btrfs_key ins;
1502 u64 parent = 0;
1503 u64 ref_root = 0;
1504 u64 flags = 0;
1505
1506 ins.objectid = node->bytenr;
1507 ins.offset = node->num_bytes;
1508 ins.type = BTRFS_EXTENT_ITEM_KEY;
1509
1510 ref = btrfs_delayed_node_to_data_ref(node);
1511 trace_run_delayed_data_ref(trans->fs_info, node, ref, node->action);
1512
1513 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1514 parent = ref->parent;
1515 ref_root = ref->root;
1516
1517 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1518 if (extent_op)
1519 flags |= extent_op->flags_to_set;
1520 ret = alloc_reserved_file_extent(trans, parent, ref_root,
1521 flags, ref->objectid,
1522 ref->offset, &ins,
1523 node->ref_mod);
1524 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1525 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
1526 ref->objectid, ref->offset,
1527 node->ref_mod, extent_op);
1528 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1529 ret = __btrfs_free_extent(trans, node, parent,
1530 ref_root, ref->objectid,
1531 ref->offset, node->ref_mod,
1532 extent_op);
1533 } else {
1534 BUG();
1535 }
1536 return ret;
1537 }
1538
__run_delayed_extent_op(struct btrfs_delayed_extent_op * extent_op,struct extent_buffer * leaf,struct btrfs_extent_item * ei)1539 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1540 struct extent_buffer *leaf,
1541 struct btrfs_extent_item *ei)
1542 {
1543 u64 flags = btrfs_extent_flags(leaf, ei);
1544 if (extent_op->update_flags) {
1545 flags |= extent_op->flags_to_set;
1546 btrfs_set_extent_flags(leaf, ei, flags);
1547 }
1548
1549 if (extent_op->update_key) {
1550 struct btrfs_tree_block_info *bi;
1551 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1552 bi = (struct btrfs_tree_block_info *)(ei + 1);
1553 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1554 }
1555 }
1556
run_delayed_extent_op(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head,struct btrfs_delayed_extent_op * extent_op)1557 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1558 struct btrfs_delayed_ref_head *head,
1559 struct btrfs_delayed_extent_op *extent_op)
1560 {
1561 struct btrfs_fs_info *fs_info = trans->fs_info;
1562 struct btrfs_root *root;
1563 struct btrfs_key key;
1564 struct btrfs_path *path;
1565 struct btrfs_extent_item *ei;
1566 struct extent_buffer *leaf;
1567 u32 item_size;
1568 int ret;
1569 int err = 0;
1570 int metadata = 1;
1571
1572 if (TRANS_ABORTED(trans))
1573 return 0;
1574
1575 if (!btrfs_fs_incompat(fs_info, SKINNY_METADATA))
1576 metadata = 0;
1577
1578 path = btrfs_alloc_path();
1579 if (!path)
1580 return -ENOMEM;
1581
1582 key.objectid = head->bytenr;
1583
1584 if (metadata) {
1585 key.type = BTRFS_METADATA_ITEM_KEY;
1586 key.offset = extent_op->level;
1587 } else {
1588 key.type = BTRFS_EXTENT_ITEM_KEY;
1589 key.offset = head->num_bytes;
1590 }
1591
1592 root = btrfs_extent_root(fs_info, key.objectid);
1593 again:
1594 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1595 if (ret < 0) {
1596 err = ret;
1597 goto out;
1598 }
1599 if (ret > 0) {
1600 if (metadata) {
1601 if (path->slots[0] > 0) {
1602 path->slots[0]--;
1603 btrfs_item_key_to_cpu(path->nodes[0], &key,
1604 path->slots[0]);
1605 if (key.objectid == head->bytenr &&
1606 key.type == BTRFS_EXTENT_ITEM_KEY &&
1607 key.offset == head->num_bytes)
1608 ret = 0;
1609 }
1610 if (ret > 0) {
1611 btrfs_release_path(path);
1612 metadata = 0;
1613
1614 key.objectid = head->bytenr;
1615 key.offset = head->num_bytes;
1616 key.type = BTRFS_EXTENT_ITEM_KEY;
1617 goto again;
1618 }
1619 } else {
1620 err = -EIO;
1621 goto out;
1622 }
1623 }
1624
1625 leaf = path->nodes[0];
1626 item_size = btrfs_item_size(leaf, path->slots[0]);
1627
1628 if (unlikely(item_size < sizeof(*ei))) {
1629 err = -EINVAL;
1630 btrfs_print_v0_err(fs_info);
1631 btrfs_abort_transaction(trans, err);
1632 goto out;
1633 }
1634
1635 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1636 __run_delayed_extent_op(extent_op, leaf, ei);
1637
1638 btrfs_mark_buffer_dirty(leaf);
1639 out:
1640 btrfs_free_path(path);
1641 return err;
1642 }
1643
run_delayed_tree_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,struct btrfs_delayed_extent_op * extent_op,int insert_reserved)1644 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1645 struct btrfs_delayed_ref_node *node,
1646 struct btrfs_delayed_extent_op *extent_op,
1647 int insert_reserved)
1648 {
1649 int ret = 0;
1650 struct btrfs_delayed_tree_ref *ref;
1651 u64 parent = 0;
1652 u64 ref_root = 0;
1653
1654 ref = btrfs_delayed_node_to_tree_ref(node);
1655 trace_run_delayed_tree_ref(trans->fs_info, node, ref, node->action);
1656
1657 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1658 parent = ref->parent;
1659 ref_root = ref->root;
1660
1661 if (node->ref_mod != 1) {
1662 btrfs_err(trans->fs_info,
1663 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
1664 node->bytenr, node->ref_mod, node->action, ref_root,
1665 parent);
1666 return -EIO;
1667 }
1668 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1669 BUG_ON(!extent_op || !extent_op->update_flags);
1670 ret = alloc_reserved_tree_block(trans, node, extent_op);
1671 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1672 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
1673 ref->level, 0, 1, extent_op);
1674 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1675 ret = __btrfs_free_extent(trans, node, parent, ref_root,
1676 ref->level, 0, 1, extent_op);
1677 } else {
1678 BUG();
1679 }
1680 return ret;
1681 }
1682
1683 /* helper function to actually process a single delayed ref entry */
run_one_delayed_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,struct btrfs_delayed_extent_op * extent_op,int insert_reserved)1684 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
1685 struct btrfs_delayed_ref_node *node,
1686 struct btrfs_delayed_extent_op *extent_op,
1687 int insert_reserved)
1688 {
1689 int ret = 0;
1690
1691 if (TRANS_ABORTED(trans)) {
1692 if (insert_reserved)
1693 btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1);
1694 return 0;
1695 }
1696
1697 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
1698 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1699 ret = run_delayed_tree_ref(trans, node, extent_op,
1700 insert_reserved);
1701 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
1702 node->type == BTRFS_SHARED_DATA_REF_KEY)
1703 ret = run_delayed_data_ref(trans, node, extent_op,
1704 insert_reserved);
1705 else
1706 BUG();
1707 if (ret && insert_reserved)
1708 btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1);
1709 if (ret < 0)
1710 btrfs_err(trans->fs_info,
1711 "failed to run delayed ref for logical %llu num_bytes %llu type %u action %u ref_mod %d: %d",
1712 node->bytenr, node->num_bytes, node->type,
1713 node->action, node->ref_mod, ret);
1714 return ret;
1715 }
1716
1717 static inline struct btrfs_delayed_ref_node *
select_delayed_ref(struct btrfs_delayed_ref_head * head)1718 select_delayed_ref(struct btrfs_delayed_ref_head *head)
1719 {
1720 struct btrfs_delayed_ref_node *ref;
1721
1722 if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
1723 return NULL;
1724
1725 /*
1726 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
1727 * This is to prevent a ref count from going down to zero, which deletes
1728 * the extent item from the extent tree, when there still are references
1729 * to add, which would fail because they would not find the extent item.
1730 */
1731 if (!list_empty(&head->ref_add_list))
1732 return list_first_entry(&head->ref_add_list,
1733 struct btrfs_delayed_ref_node, add_list);
1734
1735 ref = rb_entry(rb_first_cached(&head->ref_tree),
1736 struct btrfs_delayed_ref_node, ref_node);
1737 ASSERT(list_empty(&ref->add_list));
1738 return ref;
1739 }
1740
unselect_delayed_ref_head(struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_head * head)1741 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
1742 struct btrfs_delayed_ref_head *head)
1743 {
1744 spin_lock(&delayed_refs->lock);
1745 head->processing = 0;
1746 delayed_refs->num_heads_ready++;
1747 spin_unlock(&delayed_refs->lock);
1748 btrfs_delayed_ref_unlock(head);
1749 }
1750
cleanup_extent_op(struct btrfs_delayed_ref_head * head)1751 static struct btrfs_delayed_extent_op *cleanup_extent_op(
1752 struct btrfs_delayed_ref_head *head)
1753 {
1754 struct btrfs_delayed_extent_op *extent_op = head->extent_op;
1755
1756 if (!extent_op)
1757 return NULL;
1758
1759 if (head->must_insert_reserved) {
1760 head->extent_op = NULL;
1761 btrfs_free_delayed_extent_op(extent_op);
1762 return NULL;
1763 }
1764 return extent_op;
1765 }
1766
run_and_cleanup_extent_op(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head)1767 static int run_and_cleanup_extent_op(struct btrfs_trans_handle *trans,
1768 struct btrfs_delayed_ref_head *head)
1769 {
1770 struct btrfs_delayed_extent_op *extent_op;
1771 int ret;
1772
1773 extent_op = cleanup_extent_op(head);
1774 if (!extent_op)
1775 return 0;
1776 head->extent_op = NULL;
1777 spin_unlock(&head->lock);
1778 ret = run_delayed_extent_op(trans, head, extent_op);
1779 btrfs_free_delayed_extent_op(extent_op);
1780 return ret ? ret : 1;
1781 }
1782
btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info * fs_info,struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_head * head)1783 void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
1784 struct btrfs_delayed_ref_root *delayed_refs,
1785 struct btrfs_delayed_ref_head *head)
1786 {
1787 int nr_items = 1; /* Dropping this ref head update. */
1788
1789 /*
1790 * We had csum deletions accounted for in our delayed refs rsv, we need
1791 * to drop the csum leaves for this update from our delayed_refs_rsv.
1792 */
1793 if (head->total_ref_mod < 0 && head->is_data) {
1794 spin_lock(&delayed_refs->lock);
1795 delayed_refs->pending_csums -= head->num_bytes;
1796 spin_unlock(&delayed_refs->lock);
1797 nr_items += btrfs_csum_bytes_to_leaves(fs_info, head->num_bytes);
1798 }
1799
1800 btrfs_delayed_refs_rsv_release(fs_info, nr_items);
1801 }
1802
cleanup_ref_head(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head)1803 static int cleanup_ref_head(struct btrfs_trans_handle *trans,
1804 struct btrfs_delayed_ref_head *head)
1805 {
1806
1807 struct btrfs_fs_info *fs_info = trans->fs_info;
1808 struct btrfs_delayed_ref_root *delayed_refs;
1809 int ret;
1810
1811 delayed_refs = &trans->transaction->delayed_refs;
1812
1813 ret = run_and_cleanup_extent_op(trans, head);
1814 if (ret < 0) {
1815 unselect_delayed_ref_head(delayed_refs, head);
1816 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
1817 return ret;
1818 } else if (ret) {
1819 return ret;
1820 }
1821
1822 /*
1823 * Need to drop our head ref lock and re-acquire the delayed ref lock
1824 * and then re-check to make sure nobody got added.
1825 */
1826 spin_unlock(&head->lock);
1827 spin_lock(&delayed_refs->lock);
1828 spin_lock(&head->lock);
1829 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root) || head->extent_op) {
1830 spin_unlock(&head->lock);
1831 spin_unlock(&delayed_refs->lock);
1832 return 1;
1833 }
1834 btrfs_delete_ref_head(delayed_refs, head);
1835 spin_unlock(&head->lock);
1836 spin_unlock(&delayed_refs->lock);
1837
1838 if (head->must_insert_reserved) {
1839 btrfs_pin_extent(trans, head->bytenr, head->num_bytes, 1);
1840 if (head->is_data) {
1841 struct btrfs_root *csum_root;
1842
1843 csum_root = btrfs_csum_root(fs_info, head->bytenr);
1844 ret = btrfs_del_csums(trans, csum_root, head->bytenr,
1845 head->num_bytes);
1846 }
1847 }
1848
1849 btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
1850
1851 trace_run_delayed_ref_head(fs_info, head, 0);
1852 btrfs_delayed_ref_unlock(head);
1853 btrfs_put_delayed_ref_head(head);
1854 return ret;
1855 }
1856
btrfs_obtain_ref_head(struct btrfs_trans_handle * trans)1857 static struct btrfs_delayed_ref_head *btrfs_obtain_ref_head(
1858 struct btrfs_trans_handle *trans)
1859 {
1860 struct btrfs_delayed_ref_root *delayed_refs =
1861 &trans->transaction->delayed_refs;
1862 struct btrfs_delayed_ref_head *head = NULL;
1863 int ret;
1864
1865 spin_lock(&delayed_refs->lock);
1866 head = btrfs_select_ref_head(delayed_refs);
1867 if (!head) {
1868 spin_unlock(&delayed_refs->lock);
1869 return head;
1870 }
1871
1872 /*
1873 * Grab the lock that says we are going to process all the refs for
1874 * this head
1875 */
1876 ret = btrfs_delayed_ref_lock(delayed_refs, head);
1877 spin_unlock(&delayed_refs->lock);
1878
1879 /*
1880 * We may have dropped the spin lock to get the head mutex lock, and
1881 * that might have given someone else time to free the head. If that's
1882 * true, it has been removed from our list and we can move on.
1883 */
1884 if (ret == -EAGAIN)
1885 head = ERR_PTR(-EAGAIN);
1886
1887 return head;
1888 }
1889
btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * locked_ref,unsigned long * run_refs)1890 static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans,
1891 struct btrfs_delayed_ref_head *locked_ref,
1892 unsigned long *run_refs)
1893 {
1894 struct btrfs_fs_info *fs_info = trans->fs_info;
1895 struct btrfs_delayed_ref_root *delayed_refs;
1896 struct btrfs_delayed_extent_op *extent_op;
1897 struct btrfs_delayed_ref_node *ref;
1898 int must_insert_reserved = 0;
1899 int ret;
1900
1901 delayed_refs = &trans->transaction->delayed_refs;
1902
1903 lockdep_assert_held(&locked_ref->mutex);
1904 lockdep_assert_held(&locked_ref->lock);
1905
1906 while ((ref = select_delayed_ref(locked_ref))) {
1907 if (ref->seq &&
1908 btrfs_check_delayed_seq(fs_info, ref->seq)) {
1909 spin_unlock(&locked_ref->lock);
1910 unselect_delayed_ref_head(delayed_refs, locked_ref);
1911 return -EAGAIN;
1912 }
1913
1914 (*run_refs)++;
1915 ref->in_tree = 0;
1916 rb_erase_cached(&ref->ref_node, &locked_ref->ref_tree);
1917 RB_CLEAR_NODE(&ref->ref_node);
1918 if (!list_empty(&ref->add_list))
1919 list_del(&ref->add_list);
1920 /*
1921 * When we play the delayed ref, also correct the ref_mod on
1922 * head
1923 */
1924 switch (ref->action) {
1925 case BTRFS_ADD_DELAYED_REF:
1926 case BTRFS_ADD_DELAYED_EXTENT:
1927 locked_ref->ref_mod -= ref->ref_mod;
1928 break;
1929 case BTRFS_DROP_DELAYED_REF:
1930 locked_ref->ref_mod += ref->ref_mod;
1931 break;
1932 default:
1933 WARN_ON(1);
1934 }
1935 atomic_dec(&delayed_refs->num_entries);
1936
1937 /*
1938 * Record the must_insert_reserved flag before we drop the
1939 * spin lock.
1940 */
1941 must_insert_reserved = locked_ref->must_insert_reserved;
1942 locked_ref->must_insert_reserved = 0;
1943
1944 extent_op = locked_ref->extent_op;
1945 locked_ref->extent_op = NULL;
1946 spin_unlock(&locked_ref->lock);
1947
1948 ret = run_one_delayed_ref(trans, ref, extent_op,
1949 must_insert_reserved);
1950
1951 btrfs_free_delayed_extent_op(extent_op);
1952 if (ret) {
1953 unselect_delayed_ref_head(delayed_refs, locked_ref);
1954 btrfs_put_delayed_ref(ref);
1955 return ret;
1956 }
1957
1958 btrfs_put_delayed_ref(ref);
1959 cond_resched();
1960
1961 spin_lock(&locked_ref->lock);
1962 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
1963 }
1964
1965 return 0;
1966 }
1967
1968 /*
1969 * Returns 0 on success or if called with an already aborted transaction.
1970 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
1971 */
__btrfs_run_delayed_refs(struct btrfs_trans_handle * trans,unsigned long nr)1972 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
1973 unsigned long nr)
1974 {
1975 struct btrfs_fs_info *fs_info = trans->fs_info;
1976 struct btrfs_delayed_ref_root *delayed_refs;
1977 struct btrfs_delayed_ref_head *locked_ref = NULL;
1978 ktime_t start = ktime_get();
1979 int ret;
1980 unsigned long count = 0;
1981 unsigned long actual_count = 0;
1982
1983 delayed_refs = &trans->transaction->delayed_refs;
1984 do {
1985 if (!locked_ref) {
1986 locked_ref = btrfs_obtain_ref_head(trans);
1987 if (IS_ERR_OR_NULL(locked_ref)) {
1988 if (PTR_ERR(locked_ref) == -EAGAIN) {
1989 continue;
1990 } else {
1991 break;
1992 }
1993 }
1994 count++;
1995 }
1996 /*
1997 * We need to try and merge add/drops of the same ref since we
1998 * can run into issues with relocate dropping the implicit ref
1999 * and then it being added back again before the drop can
2000 * finish. If we merged anything we need to re-loop so we can
2001 * get a good ref.
2002 * Or we can get node references of the same type that weren't
2003 * merged when created due to bumps in the tree mod seq, and
2004 * we need to merge them to prevent adding an inline extent
2005 * backref before dropping it (triggering a BUG_ON at
2006 * insert_inline_extent_backref()).
2007 */
2008 spin_lock(&locked_ref->lock);
2009 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2010
2011 ret = btrfs_run_delayed_refs_for_head(trans, locked_ref,
2012 &actual_count);
2013 if (ret < 0 && ret != -EAGAIN) {
2014 /*
2015 * Error, btrfs_run_delayed_refs_for_head already
2016 * unlocked everything so just bail out
2017 */
2018 return ret;
2019 } else if (!ret) {
2020 /*
2021 * Success, perform the usual cleanup of a processed
2022 * head
2023 */
2024 ret = cleanup_ref_head(trans, locked_ref);
2025 if (ret > 0 ) {
2026 /* We dropped our lock, we need to loop. */
2027 ret = 0;
2028 continue;
2029 } else if (ret) {
2030 return ret;
2031 }
2032 }
2033
2034 /*
2035 * Either success case or btrfs_run_delayed_refs_for_head
2036 * returned -EAGAIN, meaning we need to select another head
2037 */
2038
2039 locked_ref = NULL;
2040 cond_resched();
2041 } while ((nr != -1 && count < nr) || locked_ref);
2042
2043 /*
2044 * We don't want to include ref heads since we can have empty ref heads
2045 * and those will drastically skew our runtime down since we just do
2046 * accounting, no actual extent tree updates.
2047 */
2048 if (actual_count > 0) {
2049 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2050 u64 avg;
2051
2052 /*
2053 * We weigh the current average higher than our current runtime
2054 * to avoid large swings in the average.
2055 */
2056 spin_lock(&delayed_refs->lock);
2057 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2058 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2059 spin_unlock(&delayed_refs->lock);
2060 }
2061 return 0;
2062 }
2063
2064 #ifdef SCRAMBLE_DELAYED_REFS
2065 /*
2066 * Normally delayed refs get processed in ascending bytenr order. This
2067 * correlates in most cases to the order added. To expose dependencies on this
2068 * order, we start to process the tree in the middle instead of the beginning
2069 */
find_middle(struct rb_root * root)2070 static u64 find_middle(struct rb_root *root)
2071 {
2072 struct rb_node *n = root->rb_node;
2073 struct btrfs_delayed_ref_node *entry;
2074 int alt = 1;
2075 u64 middle;
2076 u64 first = 0, last = 0;
2077
2078 n = rb_first(root);
2079 if (n) {
2080 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2081 first = entry->bytenr;
2082 }
2083 n = rb_last(root);
2084 if (n) {
2085 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2086 last = entry->bytenr;
2087 }
2088 n = root->rb_node;
2089
2090 while (n) {
2091 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2092 WARN_ON(!entry->in_tree);
2093
2094 middle = entry->bytenr;
2095
2096 if (alt)
2097 n = n->rb_left;
2098 else
2099 n = n->rb_right;
2100
2101 alt = 1 - alt;
2102 }
2103 return middle;
2104 }
2105 #endif
2106
2107 /*
2108 * this starts processing the delayed reference count updates and
2109 * extent insertions we have queued up so far. count can be
2110 * 0, which means to process everything in the tree at the start
2111 * of the run (but not newly added entries), or it can be some target
2112 * number you'd like to process.
2113 *
2114 * Returns 0 on success or if called with an aborted transaction
2115 * Returns <0 on error and aborts the transaction
2116 */
btrfs_run_delayed_refs(struct btrfs_trans_handle * trans,unsigned long count)2117 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2118 unsigned long count)
2119 {
2120 struct btrfs_fs_info *fs_info = trans->fs_info;
2121 struct rb_node *node;
2122 struct btrfs_delayed_ref_root *delayed_refs;
2123 struct btrfs_delayed_ref_head *head;
2124 int ret;
2125 int run_all = count == (unsigned long)-1;
2126
2127 /* We'll clean this up in btrfs_cleanup_transaction */
2128 if (TRANS_ABORTED(trans))
2129 return 0;
2130
2131 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
2132 return 0;
2133
2134 delayed_refs = &trans->transaction->delayed_refs;
2135 if (count == 0)
2136 count = delayed_refs->num_heads_ready;
2137
2138 again:
2139 #ifdef SCRAMBLE_DELAYED_REFS
2140 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
2141 #endif
2142 ret = __btrfs_run_delayed_refs(trans, count);
2143 if (ret < 0) {
2144 btrfs_abort_transaction(trans, ret);
2145 return ret;
2146 }
2147
2148 if (run_all) {
2149 btrfs_create_pending_block_groups(trans);
2150
2151 spin_lock(&delayed_refs->lock);
2152 node = rb_first_cached(&delayed_refs->href_root);
2153 if (!node) {
2154 spin_unlock(&delayed_refs->lock);
2155 goto out;
2156 }
2157 head = rb_entry(node, struct btrfs_delayed_ref_head,
2158 href_node);
2159 refcount_inc(&head->refs);
2160 spin_unlock(&delayed_refs->lock);
2161
2162 /* Mutex was contended, block until it's released and retry. */
2163 mutex_lock(&head->mutex);
2164 mutex_unlock(&head->mutex);
2165
2166 btrfs_put_delayed_ref_head(head);
2167 cond_resched();
2168 goto again;
2169 }
2170 out:
2171 return 0;
2172 }
2173
btrfs_set_disk_extent_flags(struct btrfs_trans_handle * trans,struct extent_buffer * eb,u64 flags,int level)2174 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2175 struct extent_buffer *eb, u64 flags,
2176 int level)
2177 {
2178 struct btrfs_delayed_extent_op *extent_op;
2179 int ret;
2180
2181 extent_op = btrfs_alloc_delayed_extent_op();
2182 if (!extent_op)
2183 return -ENOMEM;
2184
2185 extent_op->flags_to_set = flags;
2186 extent_op->update_flags = true;
2187 extent_op->update_key = false;
2188 extent_op->level = level;
2189
2190 ret = btrfs_add_delayed_extent_op(trans, eb->start, eb->len, extent_op);
2191 if (ret)
2192 btrfs_free_delayed_extent_op(extent_op);
2193 return ret;
2194 }
2195
check_delayed_ref(struct btrfs_root * root,struct btrfs_path * path,u64 objectid,u64 offset,u64 bytenr)2196 static noinline int check_delayed_ref(struct btrfs_root *root,
2197 struct btrfs_path *path,
2198 u64 objectid, u64 offset, u64 bytenr)
2199 {
2200 struct btrfs_delayed_ref_head *head;
2201 struct btrfs_delayed_ref_node *ref;
2202 struct btrfs_delayed_data_ref *data_ref;
2203 struct btrfs_delayed_ref_root *delayed_refs;
2204 struct btrfs_transaction *cur_trans;
2205 struct rb_node *node;
2206 int ret = 0;
2207
2208 spin_lock(&root->fs_info->trans_lock);
2209 cur_trans = root->fs_info->running_transaction;
2210 if (cur_trans)
2211 refcount_inc(&cur_trans->use_count);
2212 spin_unlock(&root->fs_info->trans_lock);
2213 if (!cur_trans)
2214 return 0;
2215
2216 delayed_refs = &cur_trans->delayed_refs;
2217 spin_lock(&delayed_refs->lock);
2218 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
2219 if (!head) {
2220 spin_unlock(&delayed_refs->lock);
2221 btrfs_put_transaction(cur_trans);
2222 return 0;
2223 }
2224
2225 if (!mutex_trylock(&head->mutex)) {
2226 if (path->nowait) {
2227 spin_unlock(&delayed_refs->lock);
2228 btrfs_put_transaction(cur_trans);
2229 return -EAGAIN;
2230 }
2231
2232 refcount_inc(&head->refs);
2233 spin_unlock(&delayed_refs->lock);
2234
2235 btrfs_release_path(path);
2236
2237 /*
2238 * Mutex was contended, block until it's released and let
2239 * caller try again
2240 */
2241 mutex_lock(&head->mutex);
2242 mutex_unlock(&head->mutex);
2243 btrfs_put_delayed_ref_head(head);
2244 btrfs_put_transaction(cur_trans);
2245 return -EAGAIN;
2246 }
2247 spin_unlock(&delayed_refs->lock);
2248
2249 spin_lock(&head->lock);
2250 /*
2251 * XXX: We should replace this with a proper search function in the
2252 * future.
2253 */
2254 for (node = rb_first_cached(&head->ref_tree); node;
2255 node = rb_next(node)) {
2256 ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
2257 /* If it's a shared ref we know a cross reference exists */
2258 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
2259 ret = 1;
2260 break;
2261 }
2262
2263 data_ref = btrfs_delayed_node_to_data_ref(ref);
2264
2265 /*
2266 * If our ref doesn't match the one we're currently looking at
2267 * then we have a cross reference.
2268 */
2269 if (data_ref->root != root->root_key.objectid ||
2270 data_ref->objectid != objectid ||
2271 data_ref->offset != offset) {
2272 ret = 1;
2273 break;
2274 }
2275 }
2276 spin_unlock(&head->lock);
2277 mutex_unlock(&head->mutex);
2278 btrfs_put_transaction(cur_trans);
2279 return ret;
2280 }
2281
check_committed_ref(struct btrfs_root * root,struct btrfs_path * path,u64 objectid,u64 offset,u64 bytenr,bool strict)2282 static noinline int check_committed_ref(struct btrfs_root *root,
2283 struct btrfs_path *path,
2284 u64 objectid, u64 offset, u64 bytenr,
2285 bool strict)
2286 {
2287 struct btrfs_fs_info *fs_info = root->fs_info;
2288 struct btrfs_root *extent_root = btrfs_extent_root(fs_info, bytenr);
2289 struct extent_buffer *leaf;
2290 struct btrfs_extent_data_ref *ref;
2291 struct btrfs_extent_inline_ref *iref;
2292 struct btrfs_extent_item *ei;
2293 struct btrfs_key key;
2294 u32 item_size;
2295 int type;
2296 int ret;
2297
2298 key.objectid = bytenr;
2299 key.offset = (u64)-1;
2300 key.type = BTRFS_EXTENT_ITEM_KEY;
2301
2302 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2303 if (ret < 0)
2304 goto out;
2305 BUG_ON(ret == 0); /* Corruption */
2306
2307 ret = -ENOENT;
2308 if (path->slots[0] == 0)
2309 goto out;
2310
2311 path->slots[0]--;
2312 leaf = path->nodes[0];
2313 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2314
2315 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2316 goto out;
2317
2318 ret = 1;
2319 item_size = btrfs_item_size(leaf, path->slots[0]);
2320 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2321
2322 /* If extent item has more than 1 inline ref then it's shared */
2323 if (item_size != sizeof(*ei) +
2324 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2325 goto out;
2326
2327 /*
2328 * If extent created before last snapshot => it's shared unless the
2329 * snapshot has been deleted. Use the heuristic if strict is false.
2330 */
2331 if (!strict &&
2332 (btrfs_extent_generation(leaf, ei) <=
2333 btrfs_root_last_snapshot(&root->root_item)))
2334 goto out;
2335
2336 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2337
2338 /* If this extent has SHARED_DATA_REF then it's shared */
2339 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
2340 if (type != BTRFS_EXTENT_DATA_REF_KEY)
2341 goto out;
2342
2343 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2344 if (btrfs_extent_refs(leaf, ei) !=
2345 btrfs_extent_data_ref_count(leaf, ref) ||
2346 btrfs_extent_data_ref_root(leaf, ref) !=
2347 root->root_key.objectid ||
2348 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2349 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2350 goto out;
2351
2352 ret = 0;
2353 out:
2354 return ret;
2355 }
2356
btrfs_cross_ref_exist(struct btrfs_root * root,u64 objectid,u64 offset,u64 bytenr,bool strict,struct btrfs_path * path)2357 int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
2358 u64 bytenr, bool strict, struct btrfs_path *path)
2359 {
2360 int ret;
2361
2362 do {
2363 ret = check_committed_ref(root, path, objectid,
2364 offset, bytenr, strict);
2365 if (ret && ret != -ENOENT)
2366 goto out;
2367
2368 ret = check_delayed_ref(root, path, objectid, offset, bytenr);
2369 } while (ret == -EAGAIN);
2370
2371 out:
2372 btrfs_release_path(path);
2373 if (btrfs_is_data_reloc_root(root))
2374 WARN_ON(ret > 0);
2375 return ret;
2376 }
2377
__btrfs_mod_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct extent_buffer * buf,int full_backref,int inc)2378 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2379 struct btrfs_root *root,
2380 struct extent_buffer *buf,
2381 int full_backref, int inc)
2382 {
2383 struct btrfs_fs_info *fs_info = root->fs_info;
2384 u64 bytenr;
2385 u64 num_bytes;
2386 u64 parent;
2387 u64 ref_root;
2388 u32 nritems;
2389 struct btrfs_key key;
2390 struct btrfs_file_extent_item *fi;
2391 struct btrfs_ref generic_ref = { 0 };
2392 bool for_reloc = btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC);
2393 int i;
2394 int action;
2395 int level;
2396 int ret = 0;
2397
2398 if (btrfs_is_testing(fs_info))
2399 return 0;
2400
2401 ref_root = btrfs_header_owner(buf);
2402 nritems = btrfs_header_nritems(buf);
2403 level = btrfs_header_level(buf);
2404
2405 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state) && level == 0)
2406 return 0;
2407
2408 if (full_backref)
2409 parent = buf->start;
2410 else
2411 parent = 0;
2412 if (inc)
2413 action = BTRFS_ADD_DELAYED_REF;
2414 else
2415 action = BTRFS_DROP_DELAYED_REF;
2416
2417 for (i = 0; i < nritems; i++) {
2418 if (level == 0) {
2419 btrfs_item_key_to_cpu(buf, &key, i);
2420 if (key.type != BTRFS_EXTENT_DATA_KEY)
2421 continue;
2422 fi = btrfs_item_ptr(buf, i,
2423 struct btrfs_file_extent_item);
2424 if (btrfs_file_extent_type(buf, fi) ==
2425 BTRFS_FILE_EXTENT_INLINE)
2426 continue;
2427 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2428 if (bytenr == 0)
2429 continue;
2430
2431 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2432 key.offset -= btrfs_file_extent_offset(buf, fi);
2433 btrfs_init_generic_ref(&generic_ref, action, bytenr,
2434 num_bytes, parent);
2435 btrfs_init_data_ref(&generic_ref, ref_root, key.objectid,
2436 key.offset, root->root_key.objectid,
2437 for_reloc);
2438 if (inc)
2439 ret = btrfs_inc_extent_ref(trans, &generic_ref);
2440 else
2441 ret = btrfs_free_extent(trans, &generic_ref);
2442 if (ret)
2443 goto fail;
2444 } else {
2445 bytenr = btrfs_node_blockptr(buf, i);
2446 num_bytes = fs_info->nodesize;
2447 btrfs_init_generic_ref(&generic_ref, action, bytenr,
2448 num_bytes, parent);
2449 btrfs_init_tree_ref(&generic_ref, level - 1, ref_root,
2450 root->root_key.objectid, for_reloc);
2451 if (inc)
2452 ret = btrfs_inc_extent_ref(trans, &generic_ref);
2453 else
2454 ret = btrfs_free_extent(trans, &generic_ref);
2455 if (ret)
2456 goto fail;
2457 }
2458 }
2459 return 0;
2460 fail:
2461 return ret;
2462 }
2463
btrfs_inc_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct extent_buffer * buf,int full_backref)2464 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2465 struct extent_buffer *buf, int full_backref)
2466 {
2467 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2468 }
2469
btrfs_dec_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct extent_buffer * buf,int full_backref)2470 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2471 struct extent_buffer *buf, int full_backref)
2472 {
2473 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2474 }
2475
get_alloc_profile_by_root(struct btrfs_root * root,int data)2476 static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data)
2477 {
2478 struct btrfs_fs_info *fs_info = root->fs_info;
2479 u64 flags;
2480 u64 ret;
2481
2482 if (data)
2483 flags = BTRFS_BLOCK_GROUP_DATA;
2484 else if (root == fs_info->chunk_root)
2485 flags = BTRFS_BLOCK_GROUP_SYSTEM;
2486 else
2487 flags = BTRFS_BLOCK_GROUP_METADATA;
2488
2489 ret = btrfs_get_alloc_profile(fs_info, flags);
2490 return ret;
2491 }
2492
first_logical_byte(struct btrfs_fs_info * fs_info)2493 static u64 first_logical_byte(struct btrfs_fs_info *fs_info)
2494 {
2495 struct rb_node *leftmost;
2496 u64 bytenr = 0;
2497
2498 read_lock(&fs_info->block_group_cache_lock);
2499 /* Get the block group with the lowest logical start address. */
2500 leftmost = rb_first_cached(&fs_info->block_group_cache_tree);
2501 if (leftmost) {
2502 struct btrfs_block_group *bg;
2503
2504 bg = rb_entry(leftmost, struct btrfs_block_group, cache_node);
2505 bytenr = bg->start;
2506 }
2507 read_unlock(&fs_info->block_group_cache_lock);
2508
2509 return bytenr;
2510 }
2511
pin_down_extent(struct btrfs_trans_handle * trans,struct btrfs_block_group * cache,u64 bytenr,u64 num_bytes,int reserved)2512 static int pin_down_extent(struct btrfs_trans_handle *trans,
2513 struct btrfs_block_group *cache,
2514 u64 bytenr, u64 num_bytes, int reserved)
2515 {
2516 struct btrfs_fs_info *fs_info = cache->fs_info;
2517
2518 spin_lock(&cache->space_info->lock);
2519 spin_lock(&cache->lock);
2520 cache->pinned += num_bytes;
2521 btrfs_space_info_update_bytes_pinned(fs_info, cache->space_info,
2522 num_bytes);
2523 if (reserved) {
2524 cache->reserved -= num_bytes;
2525 cache->space_info->bytes_reserved -= num_bytes;
2526 }
2527 spin_unlock(&cache->lock);
2528 spin_unlock(&cache->space_info->lock);
2529
2530 set_extent_dirty(&trans->transaction->pinned_extents, bytenr,
2531 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
2532 return 0;
2533 }
2534
btrfs_pin_extent(struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes,int reserved)2535 int btrfs_pin_extent(struct btrfs_trans_handle *trans,
2536 u64 bytenr, u64 num_bytes, int reserved)
2537 {
2538 struct btrfs_block_group *cache;
2539
2540 cache = btrfs_lookup_block_group(trans->fs_info, bytenr);
2541 BUG_ON(!cache); /* Logic error */
2542
2543 pin_down_extent(trans, cache, bytenr, num_bytes, reserved);
2544
2545 btrfs_put_block_group(cache);
2546 return 0;
2547 }
2548
2549 /*
2550 * this function must be called within transaction
2551 */
btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes)2552 int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
2553 u64 bytenr, u64 num_bytes)
2554 {
2555 struct btrfs_block_group *cache;
2556 int ret;
2557
2558 cache = btrfs_lookup_block_group(trans->fs_info, bytenr);
2559 if (!cache)
2560 return -EINVAL;
2561
2562 /*
2563 * Fully cache the free space first so that our pin removes the free space
2564 * from the cache.
2565 */
2566 ret = btrfs_cache_block_group(cache, true);
2567 if (ret)
2568 goto out;
2569
2570 pin_down_extent(trans, cache, bytenr, num_bytes, 0);
2571
2572 /* remove us from the free space cache (if we're there at all) */
2573 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
2574 out:
2575 btrfs_put_block_group(cache);
2576 return ret;
2577 }
2578
__exclude_logged_extent(struct btrfs_fs_info * fs_info,u64 start,u64 num_bytes)2579 static int __exclude_logged_extent(struct btrfs_fs_info *fs_info,
2580 u64 start, u64 num_bytes)
2581 {
2582 int ret;
2583 struct btrfs_block_group *block_group;
2584
2585 block_group = btrfs_lookup_block_group(fs_info, start);
2586 if (!block_group)
2587 return -EINVAL;
2588
2589 ret = btrfs_cache_block_group(block_group, true);
2590 if (ret)
2591 goto out;
2592
2593 ret = btrfs_remove_free_space(block_group, start, num_bytes);
2594 out:
2595 btrfs_put_block_group(block_group);
2596 return ret;
2597 }
2598
btrfs_exclude_logged_extents(struct extent_buffer * eb)2599 int btrfs_exclude_logged_extents(struct extent_buffer *eb)
2600 {
2601 struct btrfs_fs_info *fs_info = eb->fs_info;
2602 struct btrfs_file_extent_item *item;
2603 struct btrfs_key key;
2604 int found_type;
2605 int i;
2606 int ret = 0;
2607
2608 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS))
2609 return 0;
2610
2611 for (i = 0; i < btrfs_header_nritems(eb); i++) {
2612 btrfs_item_key_to_cpu(eb, &key, i);
2613 if (key.type != BTRFS_EXTENT_DATA_KEY)
2614 continue;
2615 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2616 found_type = btrfs_file_extent_type(eb, item);
2617 if (found_type == BTRFS_FILE_EXTENT_INLINE)
2618 continue;
2619 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
2620 continue;
2621 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
2622 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
2623 ret = __exclude_logged_extent(fs_info, key.objectid, key.offset);
2624 if (ret)
2625 break;
2626 }
2627
2628 return ret;
2629 }
2630
2631 static void
btrfs_inc_block_group_reservations(struct btrfs_block_group * bg)2632 btrfs_inc_block_group_reservations(struct btrfs_block_group *bg)
2633 {
2634 atomic_inc(&bg->reservations);
2635 }
2636
2637 /*
2638 * Returns the free cluster for the given space info and sets empty_cluster to
2639 * what it should be based on the mount options.
2640 */
2641 static struct btrfs_free_cluster *
fetch_cluster_info(struct btrfs_fs_info * fs_info,struct btrfs_space_info * space_info,u64 * empty_cluster)2642 fetch_cluster_info(struct btrfs_fs_info *fs_info,
2643 struct btrfs_space_info *space_info, u64 *empty_cluster)
2644 {
2645 struct btrfs_free_cluster *ret = NULL;
2646
2647 *empty_cluster = 0;
2648 if (btrfs_mixed_space_info(space_info))
2649 return ret;
2650
2651 if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
2652 ret = &fs_info->meta_alloc_cluster;
2653 if (btrfs_test_opt(fs_info, SSD))
2654 *empty_cluster = SZ_2M;
2655 else
2656 *empty_cluster = SZ_64K;
2657 } else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) &&
2658 btrfs_test_opt(fs_info, SSD_SPREAD)) {
2659 *empty_cluster = SZ_2M;
2660 ret = &fs_info->data_alloc_cluster;
2661 }
2662
2663 return ret;
2664 }
2665
unpin_extent_range(struct btrfs_fs_info * fs_info,u64 start,u64 end,const bool return_free_space)2666 static int unpin_extent_range(struct btrfs_fs_info *fs_info,
2667 u64 start, u64 end,
2668 const bool return_free_space)
2669 {
2670 struct btrfs_block_group *cache = NULL;
2671 struct btrfs_space_info *space_info;
2672 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
2673 struct btrfs_free_cluster *cluster = NULL;
2674 u64 len;
2675 u64 total_unpinned = 0;
2676 u64 empty_cluster = 0;
2677 bool readonly;
2678
2679 while (start <= end) {
2680 readonly = false;
2681 if (!cache ||
2682 start >= cache->start + cache->length) {
2683 if (cache)
2684 btrfs_put_block_group(cache);
2685 total_unpinned = 0;
2686 cache = btrfs_lookup_block_group(fs_info, start);
2687 BUG_ON(!cache); /* Logic error */
2688
2689 cluster = fetch_cluster_info(fs_info,
2690 cache->space_info,
2691 &empty_cluster);
2692 empty_cluster <<= 1;
2693 }
2694
2695 len = cache->start + cache->length - start;
2696 len = min(len, end + 1 - start);
2697
2698 if (return_free_space)
2699 btrfs_add_free_space(cache, start, len);
2700
2701 start += len;
2702 total_unpinned += len;
2703 space_info = cache->space_info;
2704
2705 /*
2706 * If this space cluster has been marked as fragmented and we've
2707 * unpinned enough in this block group to potentially allow a
2708 * cluster to be created inside of it go ahead and clear the
2709 * fragmented check.
2710 */
2711 if (cluster && cluster->fragmented &&
2712 total_unpinned > empty_cluster) {
2713 spin_lock(&cluster->lock);
2714 cluster->fragmented = 0;
2715 spin_unlock(&cluster->lock);
2716 }
2717
2718 spin_lock(&space_info->lock);
2719 spin_lock(&cache->lock);
2720 cache->pinned -= len;
2721 btrfs_space_info_update_bytes_pinned(fs_info, space_info, -len);
2722 space_info->max_extent_size = 0;
2723 if (cache->ro) {
2724 space_info->bytes_readonly += len;
2725 readonly = true;
2726 } else if (btrfs_is_zoned(fs_info)) {
2727 /* Need reset before reusing in a zoned block group */
2728 space_info->bytes_zone_unusable += len;
2729 readonly = true;
2730 }
2731 spin_unlock(&cache->lock);
2732 if (!readonly && return_free_space &&
2733 global_rsv->space_info == space_info) {
2734 spin_lock(&global_rsv->lock);
2735 if (!global_rsv->full) {
2736 u64 to_add = min(len, global_rsv->size -
2737 global_rsv->reserved);
2738
2739 global_rsv->reserved += to_add;
2740 btrfs_space_info_update_bytes_may_use(fs_info,
2741 space_info, to_add);
2742 if (global_rsv->reserved >= global_rsv->size)
2743 global_rsv->full = 1;
2744 len -= to_add;
2745 }
2746 spin_unlock(&global_rsv->lock);
2747 }
2748 /* Add to any tickets we may have */
2749 if (!readonly && return_free_space && len)
2750 btrfs_try_granting_tickets(fs_info, space_info);
2751 spin_unlock(&space_info->lock);
2752 }
2753
2754 if (cache)
2755 btrfs_put_block_group(cache);
2756 return 0;
2757 }
2758
btrfs_finish_extent_commit(struct btrfs_trans_handle * trans)2759 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
2760 {
2761 struct btrfs_fs_info *fs_info = trans->fs_info;
2762 struct btrfs_block_group *block_group, *tmp;
2763 struct list_head *deleted_bgs;
2764 struct extent_io_tree *unpin;
2765 u64 start;
2766 u64 end;
2767 int ret;
2768
2769 unpin = &trans->transaction->pinned_extents;
2770
2771 while (!TRANS_ABORTED(trans)) {
2772 struct extent_state *cached_state = NULL;
2773
2774 mutex_lock(&fs_info->unused_bg_unpin_mutex);
2775 ret = find_first_extent_bit(unpin, 0, &start, &end,
2776 EXTENT_DIRTY, &cached_state);
2777 if (ret) {
2778 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
2779 break;
2780 }
2781
2782 if (btrfs_test_opt(fs_info, DISCARD_SYNC))
2783 ret = btrfs_discard_extent(fs_info, start,
2784 end + 1 - start, NULL);
2785
2786 clear_extent_dirty(unpin, start, end, &cached_state);
2787 unpin_extent_range(fs_info, start, end, true);
2788 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
2789 free_extent_state(cached_state);
2790 cond_resched();
2791 }
2792
2793 if (btrfs_test_opt(fs_info, DISCARD_ASYNC)) {
2794 btrfs_discard_calc_delay(&fs_info->discard_ctl);
2795 btrfs_discard_schedule_work(&fs_info->discard_ctl, true);
2796 }
2797
2798 /*
2799 * Transaction is finished. We don't need the lock anymore. We
2800 * do need to clean up the block groups in case of a transaction
2801 * abort.
2802 */
2803 deleted_bgs = &trans->transaction->deleted_bgs;
2804 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
2805 u64 trimmed = 0;
2806
2807 ret = -EROFS;
2808 if (!TRANS_ABORTED(trans))
2809 ret = btrfs_discard_extent(fs_info,
2810 block_group->start,
2811 block_group->length,
2812 &trimmed);
2813
2814 list_del_init(&block_group->bg_list);
2815 btrfs_unfreeze_block_group(block_group);
2816 btrfs_put_block_group(block_group);
2817
2818 if (ret) {
2819 const char *errstr = btrfs_decode_error(ret);
2820 btrfs_warn(fs_info,
2821 "discard failed while removing blockgroup: errno=%d %s",
2822 ret, errstr);
2823 }
2824 }
2825
2826 return 0;
2827 }
2828
do_free_extent_accounting(struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes,bool is_data)2829 static int do_free_extent_accounting(struct btrfs_trans_handle *trans,
2830 u64 bytenr, u64 num_bytes, bool is_data)
2831 {
2832 int ret;
2833
2834 if (is_data) {
2835 struct btrfs_root *csum_root;
2836
2837 csum_root = btrfs_csum_root(trans->fs_info, bytenr);
2838 ret = btrfs_del_csums(trans, csum_root, bytenr, num_bytes);
2839 if (ret) {
2840 btrfs_abort_transaction(trans, ret);
2841 return ret;
2842 }
2843 }
2844
2845 ret = add_to_free_space_tree(trans, bytenr, num_bytes);
2846 if (ret) {
2847 btrfs_abort_transaction(trans, ret);
2848 return ret;
2849 }
2850
2851 ret = btrfs_update_block_group(trans, bytenr, num_bytes, false);
2852 if (ret)
2853 btrfs_abort_transaction(trans, ret);
2854
2855 return ret;
2856 }
2857
2858 /*
2859 * Drop one or more refs of @node.
2860 *
2861 * 1. Locate the extent refs.
2862 * It's either inline in EXTENT/METADATA_ITEM or in keyed SHARED_* item.
2863 * Locate it, then reduce the refs number or remove the ref line completely.
2864 *
2865 * 2. Update the refs count in EXTENT/METADATA_ITEM
2866 *
2867 * Inline backref case:
2868 *
2869 * in extent tree we have:
2870 *
2871 * item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 16201 itemsize 82
2872 * refs 2 gen 6 flags DATA
2873 * extent data backref root FS_TREE objectid 258 offset 0 count 1
2874 * extent data backref root FS_TREE objectid 257 offset 0 count 1
2875 *
2876 * This function gets called with:
2877 *
2878 * node->bytenr = 13631488
2879 * node->num_bytes = 1048576
2880 * root_objectid = FS_TREE
2881 * owner_objectid = 257
2882 * owner_offset = 0
2883 * refs_to_drop = 1
2884 *
2885 * Then we should get some like:
2886 *
2887 * item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 16201 itemsize 82
2888 * refs 1 gen 6 flags DATA
2889 * extent data backref root FS_TREE objectid 258 offset 0 count 1
2890 *
2891 * Keyed backref case:
2892 *
2893 * in extent tree we have:
2894 *
2895 * item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 3971 itemsize 24
2896 * refs 754 gen 6 flags DATA
2897 * [...]
2898 * item 2 key (13631488 EXTENT_DATA_REF <HASH>) itemoff 3915 itemsize 28
2899 * extent data backref root FS_TREE objectid 866 offset 0 count 1
2900 *
2901 * This function get called with:
2902 *
2903 * node->bytenr = 13631488
2904 * node->num_bytes = 1048576
2905 * root_objectid = FS_TREE
2906 * owner_objectid = 866
2907 * owner_offset = 0
2908 * refs_to_drop = 1
2909 *
2910 * Then we should get some like:
2911 *
2912 * item 0 key (13631488 EXTENT_ITEM 1048576) itemoff 3971 itemsize 24
2913 * refs 753 gen 6 flags DATA
2914 *
2915 * And that (13631488 EXTENT_DATA_REF <HASH>) gets removed.
2916 */
__btrfs_free_extent(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,u64 parent,u64 root_objectid,u64 owner_objectid,u64 owner_offset,int refs_to_drop,struct btrfs_delayed_extent_op * extent_op)2917 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
2918 struct btrfs_delayed_ref_node *node, u64 parent,
2919 u64 root_objectid, u64 owner_objectid,
2920 u64 owner_offset, int refs_to_drop,
2921 struct btrfs_delayed_extent_op *extent_op)
2922 {
2923 struct btrfs_fs_info *info = trans->fs_info;
2924 struct btrfs_key key;
2925 struct btrfs_path *path;
2926 struct btrfs_root *extent_root;
2927 struct extent_buffer *leaf;
2928 struct btrfs_extent_item *ei;
2929 struct btrfs_extent_inline_ref *iref;
2930 int ret;
2931 int is_data;
2932 int extent_slot = 0;
2933 int found_extent = 0;
2934 int num_to_del = 1;
2935 u32 item_size;
2936 u64 refs;
2937 u64 bytenr = node->bytenr;
2938 u64 num_bytes = node->num_bytes;
2939 bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
2940
2941 extent_root = btrfs_extent_root(info, bytenr);
2942 ASSERT(extent_root);
2943
2944 path = btrfs_alloc_path();
2945 if (!path)
2946 return -ENOMEM;
2947
2948 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
2949
2950 if (!is_data && refs_to_drop != 1) {
2951 btrfs_crit(info,
2952 "invalid refs_to_drop, dropping more than 1 refs for tree block %llu refs_to_drop %u",
2953 node->bytenr, refs_to_drop);
2954 ret = -EINVAL;
2955 btrfs_abort_transaction(trans, ret);
2956 goto out;
2957 }
2958
2959 if (is_data)
2960 skinny_metadata = false;
2961
2962 ret = lookup_extent_backref(trans, path, &iref, bytenr, num_bytes,
2963 parent, root_objectid, owner_objectid,
2964 owner_offset);
2965 if (ret == 0) {
2966 /*
2967 * Either the inline backref or the SHARED_DATA_REF/
2968 * SHARED_BLOCK_REF is found
2969 *
2970 * Here is a quick path to locate EXTENT/METADATA_ITEM.
2971 * It's possible the EXTENT/METADATA_ITEM is near current slot.
2972 */
2973 extent_slot = path->slots[0];
2974 while (extent_slot >= 0) {
2975 btrfs_item_key_to_cpu(path->nodes[0], &key,
2976 extent_slot);
2977 if (key.objectid != bytenr)
2978 break;
2979 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
2980 key.offset == num_bytes) {
2981 found_extent = 1;
2982 break;
2983 }
2984 if (key.type == BTRFS_METADATA_ITEM_KEY &&
2985 key.offset == owner_objectid) {
2986 found_extent = 1;
2987 break;
2988 }
2989
2990 /* Quick path didn't find the EXTEMT/METADATA_ITEM */
2991 if (path->slots[0] - extent_slot > 5)
2992 break;
2993 extent_slot--;
2994 }
2995
2996 if (!found_extent) {
2997 if (iref) {
2998 btrfs_crit(info,
2999 "invalid iref, no EXTENT/METADATA_ITEM found but has inline extent ref");
3000 btrfs_abort_transaction(trans, -EUCLEAN);
3001 goto err_dump;
3002 }
3003 /* Must be SHARED_* item, remove the backref first */
3004 ret = remove_extent_backref(trans, extent_root, path,
3005 NULL, refs_to_drop, is_data);
3006 if (ret) {
3007 btrfs_abort_transaction(trans, ret);
3008 goto out;
3009 }
3010 btrfs_release_path(path);
3011
3012 /* Slow path to locate EXTENT/METADATA_ITEM */
3013 key.objectid = bytenr;
3014 key.type = BTRFS_EXTENT_ITEM_KEY;
3015 key.offset = num_bytes;
3016
3017 if (!is_data && skinny_metadata) {
3018 key.type = BTRFS_METADATA_ITEM_KEY;
3019 key.offset = owner_objectid;
3020 }
3021
3022 ret = btrfs_search_slot(trans, extent_root,
3023 &key, path, -1, 1);
3024 if (ret > 0 && skinny_metadata && path->slots[0]) {
3025 /*
3026 * Couldn't find our skinny metadata item,
3027 * see if we have ye olde extent item.
3028 */
3029 path->slots[0]--;
3030 btrfs_item_key_to_cpu(path->nodes[0], &key,
3031 path->slots[0]);
3032 if (key.objectid == bytenr &&
3033 key.type == BTRFS_EXTENT_ITEM_KEY &&
3034 key.offset == num_bytes)
3035 ret = 0;
3036 }
3037
3038 if (ret > 0 && skinny_metadata) {
3039 skinny_metadata = false;
3040 key.objectid = bytenr;
3041 key.type = BTRFS_EXTENT_ITEM_KEY;
3042 key.offset = num_bytes;
3043 btrfs_release_path(path);
3044 ret = btrfs_search_slot(trans, extent_root,
3045 &key, path, -1, 1);
3046 }
3047
3048 if (ret) {
3049 btrfs_err(info,
3050 "umm, got %d back from search, was looking for %llu",
3051 ret, bytenr);
3052 if (ret > 0)
3053 btrfs_print_leaf(path->nodes[0]);
3054 }
3055 if (ret < 0) {
3056 btrfs_abort_transaction(trans, ret);
3057 goto out;
3058 }
3059 extent_slot = path->slots[0];
3060 }
3061 } else if (WARN_ON(ret == -ENOENT)) {
3062 btrfs_print_leaf(path->nodes[0]);
3063 btrfs_err(info,
3064 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
3065 bytenr, parent, root_objectid, owner_objectid,
3066 owner_offset);
3067 btrfs_abort_transaction(trans, ret);
3068 goto out;
3069 } else {
3070 btrfs_abort_transaction(trans, ret);
3071 goto out;
3072 }
3073
3074 leaf = path->nodes[0];
3075 item_size = btrfs_item_size(leaf, extent_slot);
3076 if (unlikely(item_size < sizeof(*ei))) {
3077 ret = -EINVAL;
3078 btrfs_print_v0_err(info);
3079 btrfs_abort_transaction(trans, ret);
3080 goto out;
3081 }
3082 ei = btrfs_item_ptr(leaf, extent_slot,
3083 struct btrfs_extent_item);
3084 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
3085 key.type == BTRFS_EXTENT_ITEM_KEY) {
3086 struct btrfs_tree_block_info *bi;
3087 if (item_size < sizeof(*ei) + sizeof(*bi)) {
3088 btrfs_crit(info,
3089 "invalid extent item size for key (%llu, %u, %llu) owner %llu, has %u expect >= %zu",
3090 key.objectid, key.type, key.offset,
3091 owner_objectid, item_size,
3092 sizeof(*ei) + sizeof(*bi));
3093 btrfs_abort_transaction(trans, -EUCLEAN);
3094 goto err_dump;
3095 }
3096 bi = (struct btrfs_tree_block_info *)(ei + 1);
3097 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
3098 }
3099
3100 refs = btrfs_extent_refs(leaf, ei);
3101 if (refs < refs_to_drop) {
3102 btrfs_crit(info,
3103 "trying to drop %d refs but we only have %llu for bytenr %llu",
3104 refs_to_drop, refs, bytenr);
3105 btrfs_abort_transaction(trans, -EUCLEAN);
3106 goto err_dump;
3107 }
3108 refs -= refs_to_drop;
3109
3110 if (refs > 0) {
3111 if (extent_op)
3112 __run_delayed_extent_op(extent_op, leaf, ei);
3113 /*
3114 * In the case of inline back ref, reference count will
3115 * be updated by remove_extent_backref
3116 */
3117 if (iref) {
3118 if (!found_extent) {
3119 btrfs_crit(info,
3120 "invalid iref, got inlined extent ref but no EXTENT/METADATA_ITEM found");
3121 btrfs_abort_transaction(trans, -EUCLEAN);
3122 goto err_dump;
3123 }
3124 } else {
3125 btrfs_set_extent_refs(leaf, ei, refs);
3126 btrfs_mark_buffer_dirty(leaf);
3127 }
3128 if (found_extent) {
3129 ret = remove_extent_backref(trans, extent_root, path,
3130 iref, refs_to_drop, is_data);
3131 if (ret) {
3132 btrfs_abort_transaction(trans, ret);
3133 goto out;
3134 }
3135 }
3136 } else {
3137 /* In this branch refs == 1 */
3138 if (found_extent) {
3139 if (is_data && refs_to_drop !=
3140 extent_data_ref_count(path, iref)) {
3141 btrfs_crit(info,
3142 "invalid refs_to_drop, current refs %u refs_to_drop %u",
3143 extent_data_ref_count(path, iref),
3144 refs_to_drop);
3145 btrfs_abort_transaction(trans, -EUCLEAN);
3146 goto err_dump;
3147 }
3148 if (iref) {
3149 if (path->slots[0] != extent_slot) {
3150 btrfs_crit(info,
3151 "invalid iref, extent item key (%llu %u %llu) doesn't have wanted iref",
3152 key.objectid, key.type,
3153 key.offset);
3154 btrfs_abort_transaction(trans, -EUCLEAN);
3155 goto err_dump;
3156 }
3157 } else {
3158 /*
3159 * No inline ref, we must be at SHARED_* item,
3160 * And it's single ref, it must be:
3161 * | extent_slot ||extent_slot + 1|
3162 * [ EXTENT/METADATA_ITEM ][ SHARED_* ITEM ]
3163 */
3164 if (path->slots[0] != extent_slot + 1) {
3165 btrfs_crit(info,
3166 "invalid SHARED_* item, previous item is not EXTENT/METADATA_ITEM");
3167 btrfs_abort_transaction(trans, -EUCLEAN);
3168 goto err_dump;
3169 }
3170 path->slots[0] = extent_slot;
3171 num_to_del = 2;
3172 }
3173 }
3174
3175 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
3176 num_to_del);
3177 if (ret) {
3178 btrfs_abort_transaction(trans, ret);
3179 goto out;
3180 }
3181 btrfs_release_path(path);
3182
3183 ret = do_free_extent_accounting(trans, bytenr, num_bytes, is_data);
3184 }
3185 btrfs_release_path(path);
3186
3187 out:
3188 btrfs_free_path(path);
3189 return ret;
3190 err_dump:
3191 /*
3192 * Leaf dump can take up a lot of log buffer, so we only do full leaf
3193 * dump for debug build.
3194 */
3195 if (IS_ENABLED(CONFIG_BTRFS_DEBUG)) {
3196 btrfs_crit(info, "path->slots[0]=%d extent_slot=%d",
3197 path->slots[0], extent_slot);
3198 btrfs_print_leaf(path->nodes[0]);
3199 }
3200
3201 btrfs_free_path(path);
3202 return -EUCLEAN;
3203 }
3204
3205 /*
3206 * when we free an block, it is possible (and likely) that we free the last
3207 * delayed ref for that extent as well. This searches the delayed ref tree for
3208 * a given extent, and if there are no other delayed refs to be processed, it
3209 * removes it from the tree.
3210 */
check_ref_cleanup(struct btrfs_trans_handle * trans,u64 bytenr)3211 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
3212 u64 bytenr)
3213 {
3214 struct btrfs_delayed_ref_head *head;
3215 struct btrfs_delayed_ref_root *delayed_refs;
3216 int ret = 0;
3217
3218 delayed_refs = &trans->transaction->delayed_refs;
3219 spin_lock(&delayed_refs->lock);
3220 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
3221 if (!head)
3222 goto out_delayed_unlock;
3223
3224 spin_lock(&head->lock);
3225 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root))
3226 goto out;
3227
3228 if (cleanup_extent_op(head) != NULL)
3229 goto out;
3230
3231 /*
3232 * waiting for the lock here would deadlock. If someone else has it
3233 * locked they are already in the process of dropping it anyway
3234 */
3235 if (!mutex_trylock(&head->mutex))
3236 goto out;
3237
3238 btrfs_delete_ref_head(delayed_refs, head);
3239 head->processing = 0;
3240
3241 spin_unlock(&head->lock);
3242 spin_unlock(&delayed_refs->lock);
3243
3244 BUG_ON(head->extent_op);
3245 if (head->must_insert_reserved)
3246 ret = 1;
3247
3248 btrfs_cleanup_ref_head_accounting(trans->fs_info, delayed_refs, head);
3249 mutex_unlock(&head->mutex);
3250 btrfs_put_delayed_ref_head(head);
3251 return ret;
3252 out:
3253 spin_unlock(&head->lock);
3254
3255 out_delayed_unlock:
3256 spin_unlock(&delayed_refs->lock);
3257 return 0;
3258 }
3259
btrfs_free_tree_block(struct btrfs_trans_handle * trans,u64 root_id,struct extent_buffer * buf,u64 parent,int last_ref)3260 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
3261 u64 root_id,
3262 struct extent_buffer *buf,
3263 u64 parent, int last_ref)
3264 {
3265 struct btrfs_fs_info *fs_info = trans->fs_info;
3266 struct btrfs_ref generic_ref = { 0 };
3267 int ret;
3268
3269 btrfs_init_generic_ref(&generic_ref, BTRFS_DROP_DELAYED_REF,
3270 buf->start, buf->len, parent);
3271 btrfs_init_tree_ref(&generic_ref, btrfs_header_level(buf),
3272 root_id, 0, false);
3273
3274 if (root_id != BTRFS_TREE_LOG_OBJECTID) {
3275 btrfs_ref_tree_mod(fs_info, &generic_ref);
3276 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, NULL);
3277 BUG_ON(ret); /* -ENOMEM */
3278 }
3279
3280 if (last_ref && btrfs_header_generation(buf) == trans->transid) {
3281 struct btrfs_block_group *cache;
3282 bool must_pin = false;
3283
3284 if (root_id != BTRFS_TREE_LOG_OBJECTID) {
3285 ret = check_ref_cleanup(trans, buf->start);
3286 if (!ret) {
3287 btrfs_redirty_list_add(trans->transaction, buf);
3288 goto out;
3289 }
3290 }
3291
3292 cache = btrfs_lookup_block_group(fs_info, buf->start);
3293
3294 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
3295 pin_down_extent(trans, cache, buf->start, buf->len, 1);
3296 btrfs_put_block_group(cache);
3297 goto out;
3298 }
3299
3300 /*
3301 * If there are tree mod log users we may have recorded mod log
3302 * operations for this node. If we re-allocate this node we
3303 * could replay operations on this node that happened when it
3304 * existed in a completely different root. For example if it
3305 * was part of root A, then was reallocated to root B, and we
3306 * are doing a btrfs_old_search_slot(root b), we could replay
3307 * operations that happened when the block was part of root A,
3308 * giving us an inconsistent view of the btree.
3309 *
3310 * We are safe from races here because at this point no other
3311 * node or root points to this extent buffer, so if after this
3312 * check a new tree mod log user joins we will not have an
3313 * existing log of operations on this node that we have to
3314 * contend with.
3315 */
3316 if (test_bit(BTRFS_FS_TREE_MOD_LOG_USERS, &fs_info->flags))
3317 must_pin = true;
3318
3319 if (must_pin || btrfs_is_zoned(fs_info)) {
3320 btrfs_redirty_list_add(trans->transaction, buf);
3321 pin_down_extent(trans, cache, buf->start, buf->len, 1);
3322 btrfs_put_block_group(cache);
3323 goto out;
3324 }
3325
3326 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
3327
3328 btrfs_add_free_space(cache, buf->start, buf->len);
3329 btrfs_free_reserved_bytes(cache, buf->len, 0);
3330 btrfs_put_block_group(cache);
3331 trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len);
3332 }
3333 out:
3334 if (last_ref) {
3335 /*
3336 * Deleting the buffer, clear the corrupt flag since it doesn't
3337 * matter anymore.
3338 */
3339 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
3340 }
3341 }
3342
3343 /* Can return -ENOMEM */
btrfs_free_extent(struct btrfs_trans_handle * trans,struct btrfs_ref * ref)3344 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref)
3345 {
3346 struct btrfs_fs_info *fs_info = trans->fs_info;
3347 int ret;
3348
3349 if (btrfs_is_testing(fs_info))
3350 return 0;
3351
3352 /*
3353 * tree log blocks never actually go into the extent allocation
3354 * tree, just update pinning info and exit early.
3355 */
3356 if ((ref->type == BTRFS_REF_METADATA &&
3357 ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID) ||
3358 (ref->type == BTRFS_REF_DATA &&
3359 ref->data_ref.owning_root == BTRFS_TREE_LOG_OBJECTID)) {
3360 /* unlocks the pinned mutex */
3361 btrfs_pin_extent(trans, ref->bytenr, ref->len, 1);
3362 ret = 0;
3363 } else if (ref->type == BTRFS_REF_METADATA) {
3364 ret = btrfs_add_delayed_tree_ref(trans, ref, NULL);
3365 } else {
3366 ret = btrfs_add_delayed_data_ref(trans, ref, 0);
3367 }
3368
3369 if (!((ref->type == BTRFS_REF_METADATA &&
3370 ref->tree_ref.owning_root == BTRFS_TREE_LOG_OBJECTID) ||
3371 (ref->type == BTRFS_REF_DATA &&
3372 ref->data_ref.owning_root == BTRFS_TREE_LOG_OBJECTID)))
3373 btrfs_ref_tree_mod(fs_info, ref);
3374
3375 return ret;
3376 }
3377
3378 enum btrfs_loop_type {
3379 LOOP_CACHING_NOWAIT,
3380 LOOP_CACHING_WAIT,
3381 LOOP_ALLOC_CHUNK,
3382 LOOP_NO_EMPTY_SIZE,
3383 };
3384
3385 static inline void
btrfs_lock_block_group(struct btrfs_block_group * cache,int delalloc)3386 btrfs_lock_block_group(struct btrfs_block_group *cache,
3387 int delalloc)
3388 {
3389 if (delalloc)
3390 down_read(&cache->data_rwsem);
3391 }
3392
btrfs_grab_block_group(struct btrfs_block_group * cache,int delalloc)3393 static inline void btrfs_grab_block_group(struct btrfs_block_group *cache,
3394 int delalloc)
3395 {
3396 btrfs_get_block_group(cache);
3397 if (delalloc)
3398 down_read(&cache->data_rwsem);
3399 }
3400
btrfs_lock_cluster(struct btrfs_block_group * block_group,struct btrfs_free_cluster * cluster,int delalloc)3401 static struct btrfs_block_group *btrfs_lock_cluster(
3402 struct btrfs_block_group *block_group,
3403 struct btrfs_free_cluster *cluster,
3404 int delalloc)
3405 __acquires(&cluster->refill_lock)
3406 {
3407 struct btrfs_block_group *used_bg = NULL;
3408
3409 spin_lock(&cluster->refill_lock);
3410 while (1) {
3411 used_bg = cluster->block_group;
3412 if (!used_bg)
3413 return NULL;
3414
3415 if (used_bg == block_group)
3416 return used_bg;
3417
3418 btrfs_get_block_group(used_bg);
3419
3420 if (!delalloc)
3421 return used_bg;
3422
3423 if (down_read_trylock(&used_bg->data_rwsem))
3424 return used_bg;
3425
3426 spin_unlock(&cluster->refill_lock);
3427
3428 /* We should only have one-level nested. */
3429 down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING);
3430
3431 spin_lock(&cluster->refill_lock);
3432 if (used_bg == cluster->block_group)
3433 return used_bg;
3434
3435 up_read(&used_bg->data_rwsem);
3436 btrfs_put_block_group(used_bg);
3437 }
3438 }
3439
3440 static inline void
btrfs_release_block_group(struct btrfs_block_group * cache,int delalloc)3441 btrfs_release_block_group(struct btrfs_block_group *cache,
3442 int delalloc)
3443 {
3444 if (delalloc)
3445 up_read(&cache->data_rwsem);
3446 btrfs_put_block_group(cache);
3447 }
3448
3449 enum btrfs_extent_allocation_policy {
3450 BTRFS_EXTENT_ALLOC_CLUSTERED,
3451 BTRFS_EXTENT_ALLOC_ZONED,
3452 };
3453
3454 /*
3455 * Structure used internally for find_free_extent() function. Wraps needed
3456 * parameters.
3457 */
3458 struct find_free_extent_ctl {
3459 /* Basic allocation info */
3460 u64 ram_bytes;
3461 u64 num_bytes;
3462 u64 min_alloc_size;
3463 u64 empty_size;
3464 u64 flags;
3465 int delalloc;
3466
3467 /* Where to start the search inside the bg */
3468 u64 search_start;
3469
3470 /* For clustered allocation */
3471 u64 empty_cluster;
3472 struct btrfs_free_cluster *last_ptr;
3473 bool use_cluster;
3474
3475 bool have_caching_bg;
3476 bool orig_have_caching_bg;
3477
3478 /* Allocation is called for tree-log */
3479 bool for_treelog;
3480
3481 /* Allocation is called for data relocation */
3482 bool for_data_reloc;
3483
3484 /* RAID index, converted from flags */
3485 int index;
3486
3487 /*
3488 * Current loop number, check find_free_extent_update_loop() for details
3489 */
3490 int loop;
3491
3492 /*
3493 * Whether we're refilling a cluster, if true we need to re-search
3494 * current block group but don't try to refill the cluster again.
3495 */
3496 bool retry_clustered;
3497
3498 /*
3499 * Whether we're updating free space cache, if true we need to re-search
3500 * current block group but don't try updating free space cache again.
3501 */
3502 bool retry_unclustered;
3503
3504 /* If current block group is cached */
3505 int cached;
3506
3507 /* Max contiguous hole found */
3508 u64 max_extent_size;
3509
3510 /* Total free space from free space cache, not always contiguous */
3511 u64 total_free_space;
3512
3513 /* Found result */
3514 u64 found_offset;
3515
3516 /* Hint where to start looking for an empty space */
3517 u64 hint_byte;
3518
3519 /* Allocation policy */
3520 enum btrfs_extent_allocation_policy policy;
3521 };
3522
3523
3524 /*
3525 * Helper function for find_free_extent().
3526 *
3527 * Return -ENOENT to inform caller that we need fallback to unclustered mode.
3528 * Return -EAGAIN to inform caller that we need to re-search this block group
3529 * Return >0 to inform caller that we find nothing
3530 * Return 0 means we have found a location and set ffe_ctl->found_offset.
3531 */
find_free_extent_clustered(struct btrfs_block_group * bg,struct find_free_extent_ctl * ffe_ctl,struct btrfs_block_group ** cluster_bg_ret)3532 static int find_free_extent_clustered(struct btrfs_block_group *bg,
3533 struct find_free_extent_ctl *ffe_ctl,
3534 struct btrfs_block_group **cluster_bg_ret)
3535 {
3536 struct btrfs_block_group *cluster_bg;
3537 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3538 u64 aligned_cluster;
3539 u64 offset;
3540 int ret;
3541
3542 cluster_bg = btrfs_lock_cluster(bg, last_ptr, ffe_ctl->delalloc);
3543 if (!cluster_bg)
3544 goto refill_cluster;
3545 if (cluster_bg != bg && (cluster_bg->ro ||
3546 !block_group_bits(cluster_bg, ffe_ctl->flags)))
3547 goto release_cluster;
3548
3549 offset = btrfs_alloc_from_cluster(cluster_bg, last_ptr,
3550 ffe_ctl->num_bytes, cluster_bg->start,
3551 &ffe_ctl->max_extent_size);
3552 if (offset) {
3553 /* We have a block, we're done */
3554 spin_unlock(&last_ptr->refill_lock);
3555 trace_btrfs_reserve_extent_cluster(cluster_bg,
3556 ffe_ctl->search_start, ffe_ctl->num_bytes);
3557 *cluster_bg_ret = cluster_bg;
3558 ffe_ctl->found_offset = offset;
3559 return 0;
3560 }
3561 WARN_ON(last_ptr->block_group != cluster_bg);
3562
3563 release_cluster:
3564 /*
3565 * If we are on LOOP_NO_EMPTY_SIZE, we can't set up a new clusters, so
3566 * lets just skip it and let the allocator find whatever block it can
3567 * find. If we reach this point, we will have tried the cluster
3568 * allocator plenty of times and not have found anything, so we are
3569 * likely way too fragmented for the clustering stuff to find anything.
3570 *
3571 * However, if the cluster is taken from the current block group,
3572 * release the cluster first, so that we stand a better chance of
3573 * succeeding in the unclustered allocation.
3574 */
3575 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE && cluster_bg != bg) {
3576 spin_unlock(&last_ptr->refill_lock);
3577 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
3578 return -ENOENT;
3579 }
3580
3581 /* This cluster didn't work out, free it and start over */
3582 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3583
3584 if (cluster_bg != bg)
3585 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
3586
3587 refill_cluster:
3588 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE) {
3589 spin_unlock(&last_ptr->refill_lock);
3590 return -ENOENT;
3591 }
3592
3593 aligned_cluster = max_t(u64,
3594 ffe_ctl->empty_cluster + ffe_ctl->empty_size,
3595 bg->full_stripe_len);
3596 ret = btrfs_find_space_cluster(bg, last_ptr, ffe_ctl->search_start,
3597 ffe_ctl->num_bytes, aligned_cluster);
3598 if (ret == 0) {
3599 /* Now pull our allocation out of this cluster */
3600 offset = btrfs_alloc_from_cluster(bg, last_ptr,
3601 ffe_ctl->num_bytes, ffe_ctl->search_start,
3602 &ffe_ctl->max_extent_size);
3603 if (offset) {
3604 /* We found one, proceed */
3605 spin_unlock(&last_ptr->refill_lock);
3606 trace_btrfs_reserve_extent_cluster(bg,
3607 ffe_ctl->search_start,
3608 ffe_ctl->num_bytes);
3609 ffe_ctl->found_offset = offset;
3610 return 0;
3611 }
3612 } else if (!ffe_ctl->cached && ffe_ctl->loop > LOOP_CACHING_NOWAIT &&
3613 !ffe_ctl->retry_clustered) {
3614 spin_unlock(&last_ptr->refill_lock);
3615
3616 ffe_ctl->retry_clustered = true;
3617 btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
3618 ffe_ctl->empty_cluster + ffe_ctl->empty_size);
3619 return -EAGAIN;
3620 }
3621 /*
3622 * At this point we either didn't find a cluster or we weren't able to
3623 * allocate a block from our cluster. Free the cluster we've been
3624 * trying to use, and go to the next block group.
3625 */
3626 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3627 spin_unlock(&last_ptr->refill_lock);
3628 return 1;
3629 }
3630
3631 /*
3632 * Return >0 to inform caller that we find nothing
3633 * Return 0 when we found an free extent and set ffe_ctrl->found_offset
3634 * Return -EAGAIN to inform caller that we need to re-search this block group
3635 */
find_free_extent_unclustered(struct btrfs_block_group * bg,struct find_free_extent_ctl * ffe_ctl)3636 static int find_free_extent_unclustered(struct btrfs_block_group *bg,
3637 struct find_free_extent_ctl *ffe_ctl)
3638 {
3639 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3640 u64 offset;
3641
3642 /*
3643 * We are doing an unclustered allocation, set the fragmented flag so
3644 * we don't bother trying to setup a cluster again until we get more
3645 * space.
3646 */
3647 if (unlikely(last_ptr)) {
3648 spin_lock(&last_ptr->lock);
3649 last_ptr->fragmented = 1;
3650 spin_unlock(&last_ptr->lock);
3651 }
3652 if (ffe_ctl->cached) {
3653 struct btrfs_free_space_ctl *free_space_ctl;
3654
3655 free_space_ctl = bg->free_space_ctl;
3656 spin_lock(&free_space_ctl->tree_lock);
3657 if (free_space_ctl->free_space <
3658 ffe_ctl->num_bytes + ffe_ctl->empty_cluster +
3659 ffe_ctl->empty_size) {
3660 ffe_ctl->total_free_space = max_t(u64,
3661 ffe_ctl->total_free_space,
3662 free_space_ctl->free_space);
3663 spin_unlock(&free_space_ctl->tree_lock);
3664 return 1;
3665 }
3666 spin_unlock(&free_space_ctl->tree_lock);
3667 }
3668
3669 offset = btrfs_find_space_for_alloc(bg, ffe_ctl->search_start,
3670 ffe_ctl->num_bytes, ffe_ctl->empty_size,
3671 &ffe_ctl->max_extent_size);
3672
3673 /*
3674 * If we didn't find a chunk, and we haven't failed on this block group
3675 * before, and this block group is in the middle of caching and we are
3676 * ok with waiting, then go ahead and wait for progress to be made, and
3677 * set @retry_unclustered to true.
3678 *
3679 * If @retry_unclustered is true then we've already waited on this
3680 * block group once and should move on to the next block group.
3681 */
3682 if (!offset && !ffe_ctl->retry_unclustered && !ffe_ctl->cached &&
3683 ffe_ctl->loop > LOOP_CACHING_NOWAIT) {
3684 btrfs_wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
3685 ffe_ctl->empty_size);
3686 ffe_ctl->retry_unclustered = true;
3687 return -EAGAIN;
3688 } else if (!offset) {
3689 return 1;
3690 }
3691 ffe_ctl->found_offset = offset;
3692 return 0;
3693 }
3694
do_allocation_clustered(struct btrfs_block_group * block_group,struct find_free_extent_ctl * ffe_ctl,struct btrfs_block_group ** bg_ret)3695 static int do_allocation_clustered(struct btrfs_block_group *block_group,
3696 struct find_free_extent_ctl *ffe_ctl,
3697 struct btrfs_block_group **bg_ret)
3698 {
3699 int ret;
3700
3701 /* We want to try and use the cluster allocator, so lets look there */
3702 if (ffe_ctl->last_ptr && ffe_ctl->use_cluster) {
3703 ret = find_free_extent_clustered(block_group, ffe_ctl, bg_ret);
3704 if (ret >= 0 || ret == -EAGAIN)
3705 return ret;
3706 /* ret == -ENOENT case falls through */
3707 }
3708
3709 return find_free_extent_unclustered(block_group, ffe_ctl);
3710 }
3711
3712 /*
3713 * Tree-log block group locking
3714 * ============================
3715 *
3716 * fs_info::treelog_bg_lock protects the fs_info::treelog_bg which
3717 * indicates the starting address of a block group, which is reserved only
3718 * for tree-log metadata.
3719 *
3720 * Lock nesting
3721 * ============
3722 *
3723 * space_info::lock
3724 * block_group::lock
3725 * fs_info::treelog_bg_lock
3726 */
3727
3728 /*
3729 * Simple allocator for sequential-only block group. It only allows sequential
3730 * allocation. No need to play with trees. This function also reserves the
3731 * bytes as in btrfs_add_reserved_bytes.
3732 */
do_allocation_zoned(struct btrfs_block_group * block_group,struct find_free_extent_ctl * ffe_ctl,struct btrfs_block_group ** bg_ret)3733 static int do_allocation_zoned(struct btrfs_block_group *block_group,
3734 struct find_free_extent_ctl *ffe_ctl,
3735 struct btrfs_block_group **bg_ret)
3736 {
3737 struct btrfs_fs_info *fs_info = block_group->fs_info;
3738 struct btrfs_space_info *space_info = block_group->space_info;
3739 struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
3740 u64 start = block_group->start;
3741 u64 num_bytes = ffe_ctl->num_bytes;
3742 u64 avail;
3743 u64 bytenr = block_group->start;
3744 u64 log_bytenr;
3745 u64 data_reloc_bytenr;
3746 int ret = 0;
3747 bool skip = false;
3748
3749 ASSERT(btrfs_is_zoned(block_group->fs_info));
3750
3751 /*
3752 * Do not allow non-tree-log blocks in the dedicated tree-log block
3753 * group, and vice versa.
3754 */
3755 spin_lock(&fs_info->treelog_bg_lock);
3756 log_bytenr = fs_info->treelog_bg;
3757 if (log_bytenr && ((ffe_ctl->for_treelog && bytenr != log_bytenr) ||
3758 (!ffe_ctl->for_treelog && bytenr == log_bytenr)))
3759 skip = true;
3760 spin_unlock(&fs_info->treelog_bg_lock);
3761 if (skip)
3762 return 1;
3763
3764 /*
3765 * Do not allow non-relocation blocks in the dedicated relocation block
3766 * group, and vice versa.
3767 */
3768 spin_lock(&fs_info->relocation_bg_lock);
3769 data_reloc_bytenr = fs_info->data_reloc_bg;
3770 if (data_reloc_bytenr &&
3771 ((ffe_ctl->for_data_reloc && bytenr != data_reloc_bytenr) ||
3772 (!ffe_ctl->for_data_reloc && bytenr == data_reloc_bytenr)))
3773 skip = true;
3774 spin_unlock(&fs_info->relocation_bg_lock);
3775 if (skip)
3776 return 1;
3777
3778 /* Check RO and no space case before trying to activate it */
3779 spin_lock(&block_group->lock);
3780 if (block_group->ro || btrfs_zoned_bg_is_full(block_group)) {
3781 ret = 1;
3782 /*
3783 * May need to clear fs_info->{treelog,data_reloc}_bg.
3784 * Return the error after taking the locks.
3785 */
3786 }
3787 spin_unlock(&block_group->lock);
3788
3789 if (!ret && !btrfs_zone_activate(block_group)) {
3790 ret = 1;
3791 /*
3792 * May need to clear fs_info->{treelog,data_reloc}_bg.
3793 * Return the error after taking the locks.
3794 */
3795 }
3796
3797 spin_lock(&space_info->lock);
3798 spin_lock(&block_group->lock);
3799 spin_lock(&fs_info->treelog_bg_lock);
3800 spin_lock(&fs_info->relocation_bg_lock);
3801
3802 if (ret)
3803 goto out;
3804
3805 ASSERT(!ffe_ctl->for_treelog ||
3806 block_group->start == fs_info->treelog_bg ||
3807 fs_info->treelog_bg == 0);
3808 ASSERT(!ffe_ctl->for_data_reloc ||
3809 block_group->start == fs_info->data_reloc_bg ||
3810 fs_info->data_reloc_bg == 0);
3811
3812 if (block_group->ro ||
3813 test_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &block_group->runtime_flags)) {
3814 ret = 1;
3815 goto out;
3816 }
3817
3818 /*
3819 * Do not allow currently using block group to be tree-log dedicated
3820 * block group.
3821 */
3822 if (ffe_ctl->for_treelog && !fs_info->treelog_bg &&
3823 (block_group->used || block_group->reserved)) {
3824 ret = 1;
3825 goto out;
3826 }
3827
3828 /*
3829 * Do not allow currently used block group to be the data relocation
3830 * dedicated block group.
3831 */
3832 if (ffe_ctl->for_data_reloc && !fs_info->data_reloc_bg &&
3833 (block_group->used || block_group->reserved)) {
3834 ret = 1;
3835 goto out;
3836 }
3837
3838 WARN_ON_ONCE(block_group->alloc_offset > block_group->zone_capacity);
3839 avail = block_group->zone_capacity - block_group->alloc_offset;
3840 if (avail < num_bytes) {
3841 if (ffe_ctl->max_extent_size < avail) {
3842 /*
3843 * With sequential allocator, free space is always
3844 * contiguous
3845 */
3846 ffe_ctl->max_extent_size = avail;
3847 ffe_ctl->total_free_space = avail;
3848 }
3849 ret = 1;
3850 goto out;
3851 }
3852
3853 if (ffe_ctl->for_treelog && !fs_info->treelog_bg)
3854 fs_info->treelog_bg = block_group->start;
3855
3856 if (ffe_ctl->for_data_reloc && !fs_info->data_reloc_bg)
3857 fs_info->data_reloc_bg = block_group->start;
3858
3859 ffe_ctl->found_offset = start + block_group->alloc_offset;
3860 block_group->alloc_offset += num_bytes;
3861 spin_lock(&ctl->tree_lock);
3862 ctl->free_space -= num_bytes;
3863 spin_unlock(&ctl->tree_lock);
3864
3865 /*
3866 * We do not check if found_offset is aligned to stripesize. The
3867 * address is anyway rewritten when using zone append writing.
3868 */
3869
3870 ffe_ctl->search_start = ffe_ctl->found_offset;
3871
3872 out:
3873 if (ret && ffe_ctl->for_treelog)
3874 fs_info->treelog_bg = 0;
3875 if (ret && ffe_ctl->for_data_reloc &&
3876 fs_info->data_reloc_bg == block_group->start) {
3877 /*
3878 * Do not allow further allocations from this block group.
3879 * Compared to increasing the ->ro, setting the
3880 * ->zoned_data_reloc_ongoing flag still allows nocow
3881 * writers to come in. See btrfs_inc_nocow_writers().
3882 *
3883 * We need to disable an allocation to avoid an allocation of
3884 * regular (non-relocation data) extent. With mix of relocation
3885 * extents and regular extents, we can dispatch WRITE commands
3886 * (for relocation extents) and ZONE APPEND commands (for
3887 * regular extents) at the same time to the same zone, which
3888 * easily break the write pointer.
3889 */
3890 set_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &block_group->runtime_flags);
3891 fs_info->data_reloc_bg = 0;
3892 }
3893 spin_unlock(&fs_info->relocation_bg_lock);
3894 spin_unlock(&fs_info->treelog_bg_lock);
3895 spin_unlock(&block_group->lock);
3896 spin_unlock(&space_info->lock);
3897 return ret;
3898 }
3899
do_allocation(struct btrfs_block_group * block_group,struct find_free_extent_ctl * ffe_ctl,struct btrfs_block_group ** bg_ret)3900 static int do_allocation(struct btrfs_block_group *block_group,
3901 struct find_free_extent_ctl *ffe_ctl,
3902 struct btrfs_block_group **bg_ret)
3903 {
3904 switch (ffe_ctl->policy) {
3905 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3906 return do_allocation_clustered(block_group, ffe_ctl, bg_ret);
3907 case BTRFS_EXTENT_ALLOC_ZONED:
3908 return do_allocation_zoned(block_group, ffe_ctl, bg_ret);
3909 default:
3910 BUG();
3911 }
3912 }
3913
release_block_group(struct btrfs_block_group * block_group,struct find_free_extent_ctl * ffe_ctl,int delalloc)3914 static void release_block_group(struct btrfs_block_group *block_group,
3915 struct find_free_extent_ctl *ffe_ctl,
3916 int delalloc)
3917 {
3918 switch (ffe_ctl->policy) {
3919 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3920 ffe_ctl->retry_clustered = false;
3921 ffe_ctl->retry_unclustered = false;
3922 break;
3923 case BTRFS_EXTENT_ALLOC_ZONED:
3924 /* Nothing to do */
3925 break;
3926 default:
3927 BUG();
3928 }
3929
3930 BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) !=
3931 ffe_ctl->index);
3932 btrfs_release_block_group(block_group, delalloc);
3933 }
3934
found_extent_clustered(struct find_free_extent_ctl * ffe_ctl,struct btrfs_key * ins)3935 static void found_extent_clustered(struct find_free_extent_ctl *ffe_ctl,
3936 struct btrfs_key *ins)
3937 {
3938 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
3939
3940 if (!ffe_ctl->use_cluster && last_ptr) {
3941 spin_lock(&last_ptr->lock);
3942 last_ptr->window_start = ins->objectid;
3943 spin_unlock(&last_ptr->lock);
3944 }
3945 }
3946
found_extent(struct find_free_extent_ctl * ffe_ctl,struct btrfs_key * ins)3947 static void found_extent(struct find_free_extent_ctl *ffe_ctl,
3948 struct btrfs_key *ins)
3949 {
3950 switch (ffe_ctl->policy) {
3951 case BTRFS_EXTENT_ALLOC_CLUSTERED:
3952 found_extent_clustered(ffe_ctl, ins);
3953 break;
3954 case BTRFS_EXTENT_ALLOC_ZONED:
3955 /* Nothing to do */
3956 break;
3957 default:
3958 BUG();
3959 }
3960 }
3961
can_allocate_chunk_zoned(struct btrfs_fs_info * fs_info,struct find_free_extent_ctl * ffe_ctl)3962 static int can_allocate_chunk_zoned(struct btrfs_fs_info *fs_info,
3963 struct find_free_extent_ctl *ffe_ctl)
3964 {
3965 /* If we can activate new zone, just allocate a chunk and use it */
3966 if (btrfs_can_activate_zone(fs_info->fs_devices, ffe_ctl->flags))
3967 return 0;
3968
3969 /*
3970 * We already reached the max active zones. Try to finish one block
3971 * group to make a room for a new block group. This is only possible
3972 * for a data block group because btrfs_zone_finish() may need to wait
3973 * for a running transaction which can cause a deadlock for metadata
3974 * allocation.
3975 */
3976 if (ffe_ctl->flags & BTRFS_BLOCK_GROUP_DATA) {
3977 int ret = btrfs_zone_finish_one_bg(fs_info);
3978
3979 if (ret == 1)
3980 return 0;
3981 else if (ret < 0)
3982 return ret;
3983 }
3984
3985 /*
3986 * If we have enough free space left in an already active block group
3987 * and we can't activate any other zone now, do not allow allocating a
3988 * new chunk and let find_free_extent() retry with a smaller size.
3989 */
3990 if (ffe_ctl->max_extent_size >= ffe_ctl->min_alloc_size)
3991 return -ENOSPC;
3992
3993 /*
3994 * Even min_alloc_size is not left in any block groups. Since we cannot
3995 * activate a new block group, allocating it may not help. Let's tell a
3996 * caller to try again and hope it progress something by writing some
3997 * parts of the region. That is only possible for data block groups,
3998 * where a part of the region can be written.
3999 */
4000 if (ffe_ctl->flags & BTRFS_BLOCK_GROUP_DATA)
4001 return -EAGAIN;
4002
4003 /*
4004 * We cannot activate a new block group and no enough space left in any
4005 * block groups. So, allocating a new block group may not help. But,
4006 * there is nothing to do anyway, so let's go with it.
4007 */
4008 return 0;
4009 }
4010
can_allocate_chunk(struct btrfs_fs_info * fs_info,struct find_free_extent_ctl * ffe_ctl)4011 static int can_allocate_chunk(struct btrfs_fs_info *fs_info,
4012 struct find_free_extent_ctl *ffe_ctl)
4013 {
4014 switch (ffe_ctl->policy) {
4015 case BTRFS_EXTENT_ALLOC_CLUSTERED:
4016 return 0;
4017 case BTRFS_EXTENT_ALLOC_ZONED:
4018 return can_allocate_chunk_zoned(fs_info, ffe_ctl);
4019 default:
4020 BUG();
4021 }
4022 }
4023
chunk_allocation_failed(struct find_free_extent_ctl * ffe_ctl)4024 static int chunk_allocation_failed(struct find_free_extent_ctl *ffe_ctl)
4025 {
4026 switch (ffe_ctl->policy) {
4027 case BTRFS_EXTENT_ALLOC_CLUSTERED:
4028 /*
4029 * If we can't allocate a new chunk we've already looped through
4030 * at least once, move on to the NO_EMPTY_SIZE case.
4031 */
4032 ffe_ctl->loop = LOOP_NO_EMPTY_SIZE;
4033 return 0;
4034 case BTRFS_EXTENT_ALLOC_ZONED:
4035 /* Give up here */
4036 return -ENOSPC;
4037 default:
4038 BUG();
4039 }
4040 }
4041
4042 /*
4043 * Return >0 means caller needs to re-search for free extent
4044 * Return 0 means we have the needed free extent.
4045 * Return <0 means we failed to locate any free extent.
4046 */
find_free_extent_update_loop(struct btrfs_fs_info * fs_info,struct btrfs_key * ins,struct find_free_extent_ctl * ffe_ctl,bool full_search)4047 static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
4048 struct btrfs_key *ins,
4049 struct find_free_extent_ctl *ffe_ctl,
4050 bool full_search)
4051 {
4052 struct btrfs_root *root = fs_info->chunk_root;
4053 int ret;
4054
4055 if ((ffe_ctl->loop == LOOP_CACHING_NOWAIT) &&
4056 ffe_ctl->have_caching_bg && !ffe_ctl->orig_have_caching_bg)
4057 ffe_ctl->orig_have_caching_bg = true;
4058
4059 if (ins->objectid) {
4060 found_extent(ffe_ctl, ins);
4061 return 0;
4062 }
4063
4064 if (ffe_ctl->loop >= LOOP_CACHING_WAIT && ffe_ctl->have_caching_bg)
4065 return 1;
4066
4067 ffe_ctl->index++;
4068 if (ffe_ctl->index < BTRFS_NR_RAID_TYPES)
4069 return 1;
4070
4071 /*
4072 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
4073 * caching kthreads as we move along
4074 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
4075 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
4076 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
4077 * again
4078 */
4079 if (ffe_ctl->loop < LOOP_NO_EMPTY_SIZE) {
4080 ffe_ctl->index = 0;
4081 if (ffe_ctl->loop == LOOP_CACHING_NOWAIT) {
4082 /*
4083 * We want to skip the LOOP_CACHING_WAIT step if we
4084 * don't have any uncached bgs and we've already done a
4085 * full search through.
4086 */
4087 if (ffe_ctl->orig_have_caching_bg || !full_search)
4088 ffe_ctl->loop = LOOP_CACHING_WAIT;
4089 else
4090 ffe_ctl->loop = LOOP_ALLOC_CHUNK;
4091 } else {
4092 ffe_ctl->loop++;
4093 }
4094
4095 if (ffe_ctl->loop == LOOP_ALLOC_CHUNK) {
4096 struct btrfs_trans_handle *trans;
4097 int exist = 0;
4098
4099 /*Check if allocation policy allows to create a new chunk */
4100 ret = can_allocate_chunk(fs_info, ffe_ctl);
4101 if (ret)
4102 return ret;
4103
4104 trans = current->journal_info;
4105 if (trans)
4106 exist = 1;
4107 else
4108 trans = btrfs_join_transaction(root);
4109
4110 if (IS_ERR(trans)) {
4111 ret = PTR_ERR(trans);
4112 return ret;
4113 }
4114
4115 ret = btrfs_chunk_alloc(trans, ffe_ctl->flags,
4116 CHUNK_ALLOC_FORCE_FOR_EXTENT);
4117
4118 /* Do not bail out on ENOSPC since we can do more. */
4119 if (ret == -ENOSPC)
4120 ret = chunk_allocation_failed(ffe_ctl);
4121 else if (ret < 0)
4122 btrfs_abort_transaction(trans, ret);
4123 else
4124 ret = 0;
4125 if (!exist)
4126 btrfs_end_transaction(trans);
4127 if (ret)
4128 return ret;
4129 }
4130
4131 if (ffe_ctl->loop == LOOP_NO_EMPTY_SIZE) {
4132 if (ffe_ctl->policy != BTRFS_EXTENT_ALLOC_CLUSTERED)
4133 return -ENOSPC;
4134
4135 /*
4136 * Don't loop again if we already have no empty_size and
4137 * no empty_cluster.
4138 */
4139 if (ffe_ctl->empty_size == 0 &&
4140 ffe_ctl->empty_cluster == 0)
4141 return -ENOSPC;
4142 ffe_ctl->empty_size = 0;
4143 ffe_ctl->empty_cluster = 0;
4144 }
4145 return 1;
4146 }
4147 return -ENOSPC;
4148 }
4149
prepare_allocation_clustered(struct btrfs_fs_info * fs_info,struct find_free_extent_ctl * ffe_ctl,struct btrfs_space_info * space_info,struct btrfs_key * ins)4150 static int prepare_allocation_clustered(struct btrfs_fs_info *fs_info,
4151 struct find_free_extent_ctl *ffe_ctl,
4152 struct btrfs_space_info *space_info,
4153 struct btrfs_key *ins)
4154 {
4155 /*
4156 * If our free space is heavily fragmented we may not be able to make
4157 * big contiguous allocations, so instead of doing the expensive search
4158 * for free space, simply return ENOSPC with our max_extent_size so we
4159 * can go ahead and search for a more manageable chunk.
4160 *
4161 * If our max_extent_size is large enough for our allocation simply
4162 * disable clustering since we will likely not be able to find enough
4163 * space to create a cluster and induce latency trying.
4164 */
4165 if (space_info->max_extent_size) {
4166 spin_lock(&space_info->lock);
4167 if (space_info->max_extent_size &&
4168 ffe_ctl->num_bytes > space_info->max_extent_size) {
4169 ins->offset = space_info->max_extent_size;
4170 spin_unlock(&space_info->lock);
4171 return -ENOSPC;
4172 } else if (space_info->max_extent_size) {
4173 ffe_ctl->use_cluster = false;
4174 }
4175 spin_unlock(&space_info->lock);
4176 }
4177
4178 ffe_ctl->last_ptr = fetch_cluster_info(fs_info, space_info,
4179 &ffe_ctl->empty_cluster);
4180 if (ffe_ctl->last_ptr) {
4181 struct btrfs_free_cluster *last_ptr = ffe_ctl->last_ptr;
4182
4183 spin_lock(&last_ptr->lock);
4184 if (last_ptr->block_group)
4185 ffe_ctl->hint_byte = last_ptr->window_start;
4186 if (last_ptr->fragmented) {
4187 /*
4188 * We still set window_start so we can keep track of the
4189 * last place we found an allocation to try and save
4190 * some time.
4191 */
4192 ffe_ctl->hint_byte = last_ptr->window_start;
4193 ffe_ctl->use_cluster = false;
4194 }
4195 spin_unlock(&last_ptr->lock);
4196 }
4197
4198 return 0;
4199 }
4200
prepare_allocation(struct btrfs_fs_info * fs_info,struct find_free_extent_ctl * ffe_ctl,struct btrfs_space_info * space_info,struct btrfs_key * ins)4201 static int prepare_allocation(struct btrfs_fs_info *fs_info,
4202 struct find_free_extent_ctl *ffe_ctl,
4203 struct btrfs_space_info *space_info,
4204 struct btrfs_key *ins)
4205 {
4206 switch (ffe_ctl->policy) {
4207 case BTRFS_EXTENT_ALLOC_CLUSTERED:
4208 return prepare_allocation_clustered(fs_info, ffe_ctl,
4209 space_info, ins);
4210 case BTRFS_EXTENT_ALLOC_ZONED:
4211 if (ffe_ctl->for_treelog) {
4212 spin_lock(&fs_info->treelog_bg_lock);
4213 if (fs_info->treelog_bg)
4214 ffe_ctl->hint_byte = fs_info->treelog_bg;
4215 spin_unlock(&fs_info->treelog_bg_lock);
4216 }
4217 if (ffe_ctl->for_data_reloc) {
4218 spin_lock(&fs_info->relocation_bg_lock);
4219 if (fs_info->data_reloc_bg)
4220 ffe_ctl->hint_byte = fs_info->data_reloc_bg;
4221 spin_unlock(&fs_info->relocation_bg_lock);
4222 }
4223 return 0;
4224 default:
4225 BUG();
4226 }
4227 }
4228
4229 /*
4230 * walks the btree of allocated extents and find a hole of a given size.
4231 * The key ins is changed to record the hole:
4232 * ins->objectid == start position
4233 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4234 * ins->offset == the size of the hole.
4235 * Any available blocks before search_start are skipped.
4236 *
4237 * If there is no suitable free space, we will record the max size of
4238 * the free space extent currently.
4239 *
4240 * The overall logic and call chain:
4241 *
4242 * find_free_extent()
4243 * |- Iterate through all block groups
4244 * | |- Get a valid block group
4245 * | |- Try to do clustered allocation in that block group
4246 * | |- Try to do unclustered allocation in that block group
4247 * | |- Check if the result is valid
4248 * | | |- If valid, then exit
4249 * | |- Jump to next block group
4250 * |
4251 * |- Push harder to find free extents
4252 * |- If not found, re-iterate all block groups
4253 */
find_free_extent(struct btrfs_root * root,struct btrfs_key * ins,struct find_free_extent_ctl * ffe_ctl)4254 static noinline int find_free_extent(struct btrfs_root *root,
4255 struct btrfs_key *ins,
4256 struct find_free_extent_ctl *ffe_ctl)
4257 {
4258 struct btrfs_fs_info *fs_info = root->fs_info;
4259 int ret = 0;
4260 int cache_block_group_error = 0;
4261 struct btrfs_block_group *block_group = NULL;
4262 struct btrfs_space_info *space_info;
4263 bool full_search = false;
4264
4265 WARN_ON(ffe_ctl->num_bytes < fs_info->sectorsize);
4266
4267 ffe_ctl->search_start = 0;
4268 /* For clustered allocation */
4269 ffe_ctl->empty_cluster = 0;
4270 ffe_ctl->last_ptr = NULL;
4271 ffe_ctl->use_cluster = true;
4272 ffe_ctl->have_caching_bg = false;
4273 ffe_ctl->orig_have_caching_bg = false;
4274 ffe_ctl->index = btrfs_bg_flags_to_raid_index(ffe_ctl->flags);
4275 ffe_ctl->loop = 0;
4276 /* For clustered allocation */
4277 ffe_ctl->retry_clustered = false;
4278 ffe_ctl->retry_unclustered = false;
4279 ffe_ctl->cached = 0;
4280 ffe_ctl->max_extent_size = 0;
4281 ffe_ctl->total_free_space = 0;
4282 ffe_ctl->found_offset = 0;
4283 ffe_ctl->policy = BTRFS_EXTENT_ALLOC_CLUSTERED;
4284
4285 if (btrfs_is_zoned(fs_info))
4286 ffe_ctl->policy = BTRFS_EXTENT_ALLOC_ZONED;
4287
4288 ins->type = BTRFS_EXTENT_ITEM_KEY;
4289 ins->objectid = 0;
4290 ins->offset = 0;
4291
4292 trace_find_free_extent(root, ffe_ctl->num_bytes, ffe_ctl->empty_size,
4293 ffe_ctl->flags);
4294
4295 space_info = btrfs_find_space_info(fs_info, ffe_ctl->flags);
4296 if (!space_info) {
4297 btrfs_err(fs_info, "No space info for %llu", ffe_ctl->flags);
4298 return -ENOSPC;
4299 }
4300
4301 ret = prepare_allocation(fs_info, ffe_ctl, space_info, ins);
4302 if (ret < 0)
4303 return ret;
4304
4305 ffe_ctl->search_start = max(ffe_ctl->search_start,
4306 first_logical_byte(fs_info));
4307 ffe_ctl->search_start = max(ffe_ctl->search_start, ffe_ctl->hint_byte);
4308 if (ffe_ctl->search_start == ffe_ctl->hint_byte) {
4309 block_group = btrfs_lookup_block_group(fs_info,
4310 ffe_ctl->search_start);
4311 /*
4312 * we don't want to use the block group if it doesn't match our
4313 * allocation bits, or if its not cached.
4314 *
4315 * However if we are re-searching with an ideal block group
4316 * picked out then we don't care that the block group is cached.
4317 */
4318 if (block_group && block_group_bits(block_group, ffe_ctl->flags) &&
4319 block_group->cached != BTRFS_CACHE_NO) {
4320 down_read(&space_info->groups_sem);
4321 if (list_empty(&block_group->list) ||
4322 block_group->ro) {
4323 /*
4324 * someone is removing this block group,
4325 * we can't jump into the have_block_group
4326 * target because our list pointers are not
4327 * valid
4328 */
4329 btrfs_put_block_group(block_group);
4330 up_read(&space_info->groups_sem);
4331 } else {
4332 ffe_ctl->index = btrfs_bg_flags_to_raid_index(
4333 block_group->flags);
4334 btrfs_lock_block_group(block_group,
4335 ffe_ctl->delalloc);
4336 goto have_block_group;
4337 }
4338 } else if (block_group) {
4339 btrfs_put_block_group(block_group);
4340 }
4341 }
4342 search:
4343 ffe_ctl->have_caching_bg = false;
4344 if (ffe_ctl->index == btrfs_bg_flags_to_raid_index(ffe_ctl->flags) ||
4345 ffe_ctl->index == 0)
4346 full_search = true;
4347 down_read(&space_info->groups_sem);
4348 list_for_each_entry(block_group,
4349 &space_info->block_groups[ffe_ctl->index], list) {
4350 struct btrfs_block_group *bg_ret;
4351
4352 /* If the block group is read-only, we can skip it entirely. */
4353 if (unlikely(block_group->ro)) {
4354 if (ffe_ctl->for_treelog)
4355 btrfs_clear_treelog_bg(block_group);
4356 if (ffe_ctl->for_data_reloc)
4357 btrfs_clear_data_reloc_bg(block_group);
4358 continue;
4359 }
4360
4361 btrfs_grab_block_group(block_group, ffe_ctl->delalloc);
4362 ffe_ctl->search_start = block_group->start;
4363
4364 /*
4365 * this can happen if we end up cycling through all the
4366 * raid types, but we want to make sure we only allocate
4367 * for the proper type.
4368 */
4369 if (!block_group_bits(block_group, ffe_ctl->flags)) {
4370 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4371 BTRFS_BLOCK_GROUP_RAID1_MASK |
4372 BTRFS_BLOCK_GROUP_RAID56_MASK |
4373 BTRFS_BLOCK_GROUP_RAID10;
4374
4375 /*
4376 * if they asked for extra copies and this block group
4377 * doesn't provide them, bail. This does allow us to
4378 * fill raid0 from raid1.
4379 */
4380 if ((ffe_ctl->flags & extra) && !(block_group->flags & extra))
4381 goto loop;
4382
4383 /*
4384 * This block group has different flags than we want.
4385 * It's possible that we have MIXED_GROUP flag but no
4386 * block group is mixed. Just skip such block group.
4387 */
4388 btrfs_release_block_group(block_group, ffe_ctl->delalloc);
4389 continue;
4390 }
4391
4392 have_block_group:
4393 ffe_ctl->cached = btrfs_block_group_done(block_group);
4394 if (unlikely(!ffe_ctl->cached)) {
4395 ffe_ctl->have_caching_bg = true;
4396 ret = btrfs_cache_block_group(block_group, false);
4397
4398 /*
4399 * If we get ENOMEM here or something else we want to
4400 * try other block groups, because it may not be fatal.
4401 * However if we can't find anything else we need to
4402 * save our return here so that we return the actual
4403 * error that caused problems, not ENOSPC.
4404 */
4405 if (ret < 0) {
4406 if (!cache_block_group_error)
4407 cache_block_group_error = ret;
4408 ret = 0;
4409 goto loop;
4410 }
4411 ret = 0;
4412 }
4413
4414 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
4415 goto loop;
4416
4417 bg_ret = NULL;
4418 ret = do_allocation(block_group, ffe_ctl, &bg_ret);
4419 if (ret == 0) {
4420 if (bg_ret && bg_ret != block_group) {
4421 btrfs_release_block_group(block_group,
4422 ffe_ctl->delalloc);
4423 block_group = bg_ret;
4424 }
4425 } else if (ret == -EAGAIN) {
4426 goto have_block_group;
4427 } else if (ret > 0) {
4428 goto loop;
4429 }
4430
4431 /* Checks */
4432 ffe_ctl->search_start = round_up(ffe_ctl->found_offset,
4433 fs_info->stripesize);
4434
4435 /* move on to the next group */
4436 if (ffe_ctl->search_start + ffe_ctl->num_bytes >
4437 block_group->start + block_group->length) {
4438 btrfs_add_free_space_unused(block_group,
4439 ffe_ctl->found_offset,
4440 ffe_ctl->num_bytes);
4441 goto loop;
4442 }
4443
4444 if (ffe_ctl->found_offset < ffe_ctl->search_start)
4445 btrfs_add_free_space_unused(block_group,
4446 ffe_ctl->found_offset,
4447 ffe_ctl->search_start - ffe_ctl->found_offset);
4448
4449 ret = btrfs_add_reserved_bytes(block_group, ffe_ctl->ram_bytes,
4450 ffe_ctl->num_bytes,
4451 ffe_ctl->delalloc);
4452 if (ret == -EAGAIN) {
4453 btrfs_add_free_space_unused(block_group,
4454 ffe_ctl->found_offset,
4455 ffe_ctl->num_bytes);
4456 goto loop;
4457 }
4458 btrfs_inc_block_group_reservations(block_group);
4459
4460 /* we are all good, lets return */
4461 ins->objectid = ffe_ctl->search_start;
4462 ins->offset = ffe_ctl->num_bytes;
4463
4464 trace_btrfs_reserve_extent(block_group, ffe_ctl->search_start,
4465 ffe_ctl->num_bytes);
4466 btrfs_release_block_group(block_group, ffe_ctl->delalloc);
4467 break;
4468 loop:
4469 release_block_group(block_group, ffe_ctl, ffe_ctl->delalloc);
4470 cond_resched();
4471 }
4472 up_read(&space_info->groups_sem);
4473
4474 ret = find_free_extent_update_loop(fs_info, ins, ffe_ctl, full_search);
4475 if (ret > 0)
4476 goto search;
4477
4478 if (ret == -ENOSPC && !cache_block_group_error) {
4479 /*
4480 * Use ffe_ctl->total_free_space as fallback if we can't find
4481 * any contiguous hole.
4482 */
4483 if (!ffe_ctl->max_extent_size)
4484 ffe_ctl->max_extent_size = ffe_ctl->total_free_space;
4485 spin_lock(&space_info->lock);
4486 space_info->max_extent_size = ffe_ctl->max_extent_size;
4487 spin_unlock(&space_info->lock);
4488 ins->offset = ffe_ctl->max_extent_size;
4489 } else if (ret == -ENOSPC) {
4490 ret = cache_block_group_error;
4491 }
4492 return ret;
4493 }
4494
4495 /*
4496 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
4497 * hole that is at least as big as @num_bytes.
4498 *
4499 * @root - The root that will contain this extent
4500 *
4501 * @ram_bytes - The amount of space in ram that @num_bytes take. This
4502 * is used for accounting purposes. This value differs
4503 * from @num_bytes only in the case of compressed extents.
4504 *
4505 * @num_bytes - Number of bytes to allocate on-disk.
4506 *
4507 * @min_alloc_size - Indicates the minimum amount of space that the
4508 * allocator should try to satisfy. In some cases
4509 * @num_bytes may be larger than what is required and if
4510 * the filesystem is fragmented then allocation fails.
4511 * However, the presence of @min_alloc_size gives a
4512 * chance to try and satisfy the smaller allocation.
4513 *
4514 * @empty_size - A hint that you plan on doing more COW. This is the
4515 * size in bytes the allocator should try to find free
4516 * next to the block it returns. This is just a hint and
4517 * may be ignored by the allocator.
4518 *
4519 * @hint_byte - Hint to the allocator to start searching above the byte
4520 * address passed. It might be ignored.
4521 *
4522 * @ins - This key is modified to record the found hole. It will
4523 * have the following values:
4524 * ins->objectid == start position
4525 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4526 * ins->offset == the size of the hole.
4527 *
4528 * @is_data - Boolean flag indicating whether an extent is
4529 * allocated for data (true) or metadata (false)
4530 *
4531 * @delalloc - Boolean flag indicating whether this allocation is for
4532 * delalloc or not. If 'true' data_rwsem of block groups
4533 * is going to be acquired.
4534 *
4535 *
4536 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
4537 * case -ENOSPC is returned then @ins->offset will contain the size of the
4538 * largest available hole the allocator managed to find.
4539 */
btrfs_reserve_extent(struct btrfs_root * root,u64 ram_bytes,u64 num_bytes,u64 min_alloc_size,u64 empty_size,u64 hint_byte,struct btrfs_key * ins,int is_data,int delalloc)4540 int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
4541 u64 num_bytes, u64 min_alloc_size,
4542 u64 empty_size, u64 hint_byte,
4543 struct btrfs_key *ins, int is_data, int delalloc)
4544 {
4545 struct btrfs_fs_info *fs_info = root->fs_info;
4546 struct find_free_extent_ctl ffe_ctl = {};
4547 bool final_tried = num_bytes == min_alloc_size;
4548 u64 flags;
4549 int ret;
4550 bool for_treelog = (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
4551 bool for_data_reloc = (btrfs_is_data_reloc_root(root) && is_data);
4552
4553 flags = get_alloc_profile_by_root(root, is_data);
4554 again:
4555 WARN_ON(num_bytes < fs_info->sectorsize);
4556
4557 ffe_ctl.ram_bytes = ram_bytes;
4558 ffe_ctl.num_bytes = num_bytes;
4559 ffe_ctl.min_alloc_size = min_alloc_size;
4560 ffe_ctl.empty_size = empty_size;
4561 ffe_ctl.flags = flags;
4562 ffe_ctl.delalloc = delalloc;
4563 ffe_ctl.hint_byte = hint_byte;
4564 ffe_ctl.for_treelog = for_treelog;
4565 ffe_ctl.for_data_reloc = for_data_reloc;
4566
4567 ret = find_free_extent(root, ins, &ffe_ctl);
4568 if (!ret && !is_data) {
4569 btrfs_dec_block_group_reservations(fs_info, ins->objectid);
4570 } else if (ret == -ENOSPC) {
4571 if (!final_tried && ins->offset) {
4572 num_bytes = min(num_bytes >> 1, ins->offset);
4573 num_bytes = round_down(num_bytes,
4574 fs_info->sectorsize);
4575 num_bytes = max(num_bytes, min_alloc_size);
4576 ram_bytes = num_bytes;
4577 if (num_bytes == min_alloc_size)
4578 final_tried = true;
4579 goto again;
4580 } else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
4581 struct btrfs_space_info *sinfo;
4582
4583 sinfo = btrfs_find_space_info(fs_info, flags);
4584 btrfs_err(fs_info,
4585 "allocation failed flags %llu, wanted %llu tree-log %d, relocation: %d",
4586 flags, num_bytes, for_treelog, for_data_reloc);
4587 if (sinfo)
4588 btrfs_dump_space_info(fs_info, sinfo,
4589 num_bytes, 1);
4590 }
4591 }
4592
4593 return ret;
4594 }
4595
btrfs_free_reserved_extent(struct btrfs_fs_info * fs_info,u64 start,u64 len,int delalloc)4596 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
4597 u64 start, u64 len, int delalloc)
4598 {
4599 struct btrfs_block_group *cache;
4600
4601 cache = btrfs_lookup_block_group(fs_info, start);
4602 if (!cache) {
4603 btrfs_err(fs_info, "Unable to find block group for %llu",
4604 start);
4605 return -ENOSPC;
4606 }
4607
4608 btrfs_add_free_space(cache, start, len);
4609 btrfs_free_reserved_bytes(cache, len, delalloc);
4610 trace_btrfs_reserved_extent_free(fs_info, start, len);
4611
4612 btrfs_put_block_group(cache);
4613 return 0;
4614 }
4615
btrfs_pin_reserved_extent(struct btrfs_trans_handle * trans,u64 start,u64 len)4616 int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start,
4617 u64 len)
4618 {
4619 struct btrfs_block_group *cache;
4620 int ret = 0;
4621
4622 cache = btrfs_lookup_block_group(trans->fs_info, start);
4623 if (!cache) {
4624 btrfs_err(trans->fs_info, "unable to find block group for %llu",
4625 start);
4626 return -ENOSPC;
4627 }
4628
4629 ret = pin_down_extent(trans, cache, start, len, 1);
4630 btrfs_put_block_group(cache);
4631 return ret;
4632 }
4633
alloc_reserved_extent(struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes)4634 static int alloc_reserved_extent(struct btrfs_trans_handle *trans, u64 bytenr,
4635 u64 num_bytes)
4636 {
4637 struct btrfs_fs_info *fs_info = trans->fs_info;
4638 int ret;
4639
4640 ret = remove_from_free_space_tree(trans, bytenr, num_bytes);
4641 if (ret)
4642 return ret;
4643
4644 ret = btrfs_update_block_group(trans, bytenr, num_bytes, true);
4645 if (ret) {
4646 ASSERT(!ret);
4647 btrfs_err(fs_info, "update block group failed for %llu %llu",
4648 bytenr, num_bytes);
4649 return ret;
4650 }
4651
4652 trace_btrfs_reserved_extent_alloc(fs_info, bytenr, num_bytes);
4653 return 0;
4654 }
4655
alloc_reserved_file_extent(struct btrfs_trans_handle * trans,u64 parent,u64 root_objectid,u64 flags,u64 owner,u64 offset,struct btrfs_key * ins,int ref_mod)4656 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4657 u64 parent, u64 root_objectid,
4658 u64 flags, u64 owner, u64 offset,
4659 struct btrfs_key *ins, int ref_mod)
4660 {
4661 struct btrfs_fs_info *fs_info = trans->fs_info;
4662 struct btrfs_root *extent_root;
4663 int ret;
4664 struct btrfs_extent_item *extent_item;
4665 struct btrfs_extent_inline_ref *iref;
4666 struct btrfs_path *path;
4667 struct extent_buffer *leaf;
4668 int type;
4669 u32 size;
4670
4671 if (parent > 0)
4672 type = BTRFS_SHARED_DATA_REF_KEY;
4673 else
4674 type = BTRFS_EXTENT_DATA_REF_KEY;
4675
4676 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
4677
4678 path = btrfs_alloc_path();
4679 if (!path)
4680 return -ENOMEM;
4681
4682 extent_root = btrfs_extent_root(fs_info, ins->objectid);
4683 ret = btrfs_insert_empty_item(trans, extent_root, path, ins, size);
4684 if (ret) {
4685 btrfs_free_path(path);
4686 return ret;
4687 }
4688
4689 leaf = path->nodes[0];
4690 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4691 struct btrfs_extent_item);
4692 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
4693 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4694 btrfs_set_extent_flags(leaf, extent_item,
4695 flags | BTRFS_EXTENT_FLAG_DATA);
4696
4697 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4698 btrfs_set_extent_inline_ref_type(leaf, iref, type);
4699 if (parent > 0) {
4700 struct btrfs_shared_data_ref *ref;
4701 ref = (struct btrfs_shared_data_ref *)(iref + 1);
4702 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4703 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
4704 } else {
4705 struct btrfs_extent_data_ref *ref;
4706 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
4707 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
4708 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
4709 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
4710 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
4711 }
4712
4713 btrfs_mark_buffer_dirty(path->nodes[0]);
4714 btrfs_free_path(path);
4715
4716 return alloc_reserved_extent(trans, ins->objectid, ins->offset);
4717 }
4718
alloc_reserved_tree_block(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * node,struct btrfs_delayed_extent_op * extent_op)4719 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
4720 struct btrfs_delayed_ref_node *node,
4721 struct btrfs_delayed_extent_op *extent_op)
4722 {
4723 struct btrfs_fs_info *fs_info = trans->fs_info;
4724 struct btrfs_root *extent_root;
4725 int ret;
4726 struct btrfs_extent_item *extent_item;
4727 struct btrfs_key extent_key;
4728 struct btrfs_tree_block_info *block_info;
4729 struct btrfs_extent_inline_ref *iref;
4730 struct btrfs_path *path;
4731 struct extent_buffer *leaf;
4732 struct btrfs_delayed_tree_ref *ref;
4733 u32 size = sizeof(*extent_item) + sizeof(*iref);
4734 u64 flags = extent_op->flags_to_set;
4735 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
4736
4737 ref = btrfs_delayed_node_to_tree_ref(node);
4738
4739 extent_key.objectid = node->bytenr;
4740 if (skinny_metadata) {
4741 extent_key.offset = ref->level;
4742 extent_key.type = BTRFS_METADATA_ITEM_KEY;
4743 } else {
4744 extent_key.offset = node->num_bytes;
4745 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
4746 size += sizeof(*block_info);
4747 }
4748
4749 path = btrfs_alloc_path();
4750 if (!path)
4751 return -ENOMEM;
4752
4753 extent_root = btrfs_extent_root(fs_info, extent_key.objectid);
4754 ret = btrfs_insert_empty_item(trans, extent_root, path, &extent_key,
4755 size);
4756 if (ret) {
4757 btrfs_free_path(path);
4758 return ret;
4759 }
4760
4761 leaf = path->nodes[0];
4762 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4763 struct btrfs_extent_item);
4764 btrfs_set_extent_refs(leaf, extent_item, 1);
4765 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4766 btrfs_set_extent_flags(leaf, extent_item,
4767 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
4768
4769 if (skinny_metadata) {
4770 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4771 } else {
4772 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
4773 btrfs_set_tree_block_key(leaf, block_info, &extent_op->key);
4774 btrfs_set_tree_block_level(leaf, block_info, ref->level);
4775 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
4776 }
4777
4778 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
4779 btrfs_set_extent_inline_ref_type(leaf, iref,
4780 BTRFS_SHARED_BLOCK_REF_KEY);
4781 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->parent);
4782 } else {
4783 btrfs_set_extent_inline_ref_type(leaf, iref,
4784 BTRFS_TREE_BLOCK_REF_KEY);
4785 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->root);
4786 }
4787
4788 btrfs_mark_buffer_dirty(leaf);
4789 btrfs_free_path(path);
4790
4791 return alloc_reserved_extent(trans, node->bytenr, fs_info->nodesize);
4792 }
4793
btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 owner,u64 offset,u64 ram_bytes,struct btrfs_key * ins)4794 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4795 struct btrfs_root *root, u64 owner,
4796 u64 offset, u64 ram_bytes,
4797 struct btrfs_key *ins)
4798 {
4799 struct btrfs_ref generic_ref = { 0 };
4800
4801 BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
4802
4803 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
4804 ins->objectid, ins->offset, 0);
4805 btrfs_init_data_ref(&generic_ref, root->root_key.objectid, owner,
4806 offset, 0, false);
4807 btrfs_ref_tree_mod(root->fs_info, &generic_ref);
4808
4809 return btrfs_add_delayed_data_ref(trans, &generic_ref, ram_bytes);
4810 }
4811
4812 /*
4813 * this is used by the tree logging recovery code. It records that
4814 * an extent has been allocated and makes sure to clear the free
4815 * space cache bits as well
4816 */
btrfs_alloc_logged_file_extent(struct btrfs_trans_handle * trans,u64 root_objectid,u64 owner,u64 offset,struct btrfs_key * ins)4817 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
4818 u64 root_objectid, u64 owner, u64 offset,
4819 struct btrfs_key *ins)
4820 {
4821 struct btrfs_fs_info *fs_info = trans->fs_info;
4822 int ret;
4823 struct btrfs_block_group *block_group;
4824 struct btrfs_space_info *space_info;
4825
4826 /*
4827 * Mixed block groups will exclude before processing the log so we only
4828 * need to do the exclude dance if this fs isn't mixed.
4829 */
4830 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
4831 ret = __exclude_logged_extent(fs_info, ins->objectid,
4832 ins->offset);
4833 if (ret)
4834 return ret;
4835 }
4836
4837 block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
4838 if (!block_group)
4839 return -EINVAL;
4840
4841 space_info = block_group->space_info;
4842 spin_lock(&space_info->lock);
4843 spin_lock(&block_group->lock);
4844 space_info->bytes_reserved += ins->offset;
4845 block_group->reserved += ins->offset;
4846 spin_unlock(&block_group->lock);
4847 spin_unlock(&space_info->lock);
4848
4849 ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner,
4850 offset, ins, 1);
4851 if (ret)
4852 btrfs_pin_extent(trans, ins->objectid, ins->offset, 1);
4853 btrfs_put_block_group(block_group);
4854 return ret;
4855 }
4856
4857 static struct extent_buffer *
btrfs_init_new_buffer(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 bytenr,int level,u64 owner,enum btrfs_lock_nesting nest)4858 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
4859 u64 bytenr, int level, u64 owner,
4860 enum btrfs_lock_nesting nest)
4861 {
4862 struct btrfs_fs_info *fs_info = root->fs_info;
4863 struct extent_buffer *buf;
4864 u64 lockdep_owner = owner;
4865
4866 buf = btrfs_find_create_tree_block(fs_info, bytenr, owner, level);
4867 if (IS_ERR(buf))
4868 return buf;
4869
4870 /*
4871 * Extra safety check in case the extent tree is corrupted and extent
4872 * allocator chooses to use a tree block which is already used and
4873 * locked.
4874 */
4875 if (buf->lock_owner == current->pid) {
4876 btrfs_err_rl(fs_info,
4877 "tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected",
4878 buf->start, btrfs_header_owner(buf), current->pid);
4879 free_extent_buffer(buf);
4880 return ERR_PTR(-EUCLEAN);
4881 }
4882
4883 /*
4884 * The reloc trees are just snapshots, so we need them to appear to be
4885 * just like any other fs tree WRT lockdep.
4886 *
4887 * The exception however is in replace_path() in relocation, where we
4888 * hold the lock on the original fs root and then search for the reloc
4889 * root. At that point we need to make sure any reloc root buffers are
4890 * set to the BTRFS_TREE_RELOC_OBJECTID lockdep class in order to make
4891 * lockdep happy.
4892 */
4893 if (lockdep_owner == BTRFS_TREE_RELOC_OBJECTID &&
4894 !test_bit(BTRFS_ROOT_RESET_LOCKDEP_CLASS, &root->state))
4895 lockdep_owner = BTRFS_FS_TREE_OBJECTID;
4896
4897 /* btrfs_clean_tree_block() accesses generation field. */
4898 btrfs_set_header_generation(buf, trans->transid);
4899
4900 /*
4901 * This needs to stay, because we could allocate a freed block from an
4902 * old tree into a new tree, so we need to make sure this new block is
4903 * set to the appropriate level and owner.
4904 */
4905 btrfs_set_buffer_lockdep_class(lockdep_owner, buf, level);
4906
4907 __btrfs_tree_lock(buf, nest);
4908 btrfs_clean_tree_block(buf);
4909 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
4910 clear_bit(EXTENT_BUFFER_NO_CHECK, &buf->bflags);
4911
4912 set_extent_buffer_uptodate(buf);
4913
4914 memzero_extent_buffer(buf, 0, sizeof(struct btrfs_header));
4915 btrfs_set_header_level(buf, level);
4916 btrfs_set_header_bytenr(buf, buf->start);
4917 btrfs_set_header_generation(buf, trans->transid);
4918 btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
4919 btrfs_set_header_owner(buf, owner);
4920 write_extent_buffer_fsid(buf, fs_info->fs_devices->metadata_uuid);
4921 write_extent_buffer_chunk_tree_uuid(buf, fs_info->chunk_tree_uuid);
4922 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
4923 buf->log_index = root->log_transid % 2;
4924 /*
4925 * we allow two log transactions at a time, use different
4926 * EXTENT bit to differentiate dirty pages.
4927 */
4928 if (buf->log_index == 0)
4929 set_extent_dirty(&root->dirty_log_pages, buf->start,
4930 buf->start + buf->len - 1, GFP_NOFS);
4931 else
4932 set_extent_new(&root->dirty_log_pages, buf->start,
4933 buf->start + buf->len - 1);
4934 } else {
4935 buf->log_index = -1;
4936 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
4937 buf->start + buf->len - 1, GFP_NOFS);
4938 }
4939 /* this returns a buffer locked for blocking */
4940 return buf;
4941 }
4942
4943 /*
4944 * finds a free extent and does all the dirty work required for allocation
4945 * returns the tree buffer or an ERR_PTR on error.
4946 */
btrfs_alloc_tree_block(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 parent,u64 root_objectid,const struct btrfs_disk_key * key,int level,u64 hint,u64 empty_size,enum btrfs_lock_nesting nest)4947 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
4948 struct btrfs_root *root,
4949 u64 parent, u64 root_objectid,
4950 const struct btrfs_disk_key *key,
4951 int level, u64 hint,
4952 u64 empty_size,
4953 enum btrfs_lock_nesting nest)
4954 {
4955 struct btrfs_fs_info *fs_info = root->fs_info;
4956 struct btrfs_key ins;
4957 struct btrfs_block_rsv *block_rsv;
4958 struct extent_buffer *buf;
4959 struct btrfs_delayed_extent_op *extent_op;
4960 struct btrfs_ref generic_ref = { 0 };
4961 u64 flags = 0;
4962 int ret;
4963 u32 blocksize = fs_info->nodesize;
4964 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
4965
4966 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4967 if (btrfs_is_testing(fs_info)) {
4968 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
4969 level, root_objectid, nest);
4970 if (!IS_ERR(buf))
4971 root->alloc_bytenr += blocksize;
4972 return buf;
4973 }
4974 #endif
4975
4976 block_rsv = btrfs_use_block_rsv(trans, root, blocksize);
4977 if (IS_ERR(block_rsv))
4978 return ERR_CAST(block_rsv);
4979
4980 ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize,
4981 empty_size, hint, &ins, 0, 0);
4982 if (ret)
4983 goto out_unuse;
4984
4985 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level,
4986 root_objectid, nest);
4987 if (IS_ERR(buf)) {
4988 ret = PTR_ERR(buf);
4989 goto out_free_reserved;
4990 }
4991
4992 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
4993 if (parent == 0)
4994 parent = ins.objectid;
4995 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
4996 } else
4997 BUG_ON(parent > 0);
4998
4999 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5000 extent_op = btrfs_alloc_delayed_extent_op();
5001 if (!extent_op) {
5002 ret = -ENOMEM;
5003 goto out_free_buf;
5004 }
5005 if (key)
5006 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5007 else
5008 memset(&extent_op->key, 0, sizeof(extent_op->key));
5009 extent_op->flags_to_set = flags;
5010 extent_op->update_key = skinny_metadata ? false : true;
5011 extent_op->update_flags = true;
5012 extent_op->level = level;
5013
5014 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
5015 ins.objectid, ins.offset, parent);
5016 btrfs_init_tree_ref(&generic_ref, level, root_objectid,
5017 root->root_key.objectid, false);
5018 btrfs_ref_tree_mod(fs_info, &generic_ref);
5019 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, extent_op);
5020 if (ret)
5021 goto out_free_delayed;
5022 }
5023 return buf;
5024
5025 out_free_delayed:
5026 btrfs_free_delayed_extent_op(extent_op);
5027 out_free_buf:
5028 btrfs_tree_unlock(buf);
5029 free_extent_buffer(buf);
5030 out_free_reserved:
5031 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
5032 out_unuse:
5033 btrfs_unuse_block_rsv(fs_info, block_rsv, blocksize);
5034 return ERR_PTR(ret);
5035 }
5036
5037 struct walk_control {
5038 u64 refs[BTRFS_MAX_LEVEL];
5039 u64 flags[BTRFS_MAX_LEVEL];
5040 struct btrfs_key update_progress;
5041 struct btrfs_key drop_progress;
5042 int drop_level;
5043 int stage;
5044 int level;
5045 int shared_level;
5046 int update_ref;
5047 int keep_locks;
5048 int reada_slot;
5049 int reada_count;
5050 int restarted;
5051 };
5052
5053 #define DROP_REFERENCE 1
5054 #define UPDATE_BACKREF 2
5055
reada_walk_down(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct walk_control * wc,struct btrfs_path * path)5056 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5057 struct btrfs_root *root,
5058 struct walk_control *wc,
5059 struct btrfs_path *path)
5060 {
5061 struct btrfs_fs_info *fs_info = root->fs_info;
5062 u64 bytenr;
5063 u64 generation;
5064 u64 refs;
5065 u64 flags;
5066 u32 nritems;
5067 struct btrfs_key key;
5068 struct extent_buffer *eb;
5069 int ret;
5070 int slot;
5071 int nread = 0;
5072
5073 if (path->slots[wc->level] < wc->reada_slot) {
5074 wc->reada_count = wc->reada_count * 2 / 3;
5075 wc->reada_count = max(wc->reada_count, 2);
5076 } else {
5077 wc->reada_count = wc->reada_count * 3 / 2;
5078 wc->reada_count = min_t(int, wc->reada_count,
5079 BTRFS_NODEPTRS_PER_BLOCK(fs_info));
5080 }
5081
5082 eb = path->nodes[wc->level];
5083 nritems = btrfs_header_nritems(eb);
5084
5085 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5086 if (nread >= wc->reada_count)
5087 break;
5088
5089 cond_resched();
5090 bytenr = btrfs_node_blockptr(eb, slot);
5091 generation = btrfs_node_ptr_generation(eb, slot);
5092
5093 if (slot == path->slots[wc->level])
5094 goto reada;
5095
5096 if (wc->stage == UPDATE_BACKREF &&
5097 generation <= root->root_key.offset)
5098 continue;
5099
5100 /* We don't lock the tree block, it's OK to be racy here */
5101 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr,
5102 wc->level - 1, 1, &refs,
5103 &flags);
5104 /* We don't care about errors in readahead. */
5105 if (ret < 0)
5106 continue;
5107 BUG_ON(refs == 0);
5108
5109 if (wc->stage == DROP_REFERENCE) {
5110 if (refs == 1)
5111 goto reada;
5112
5113 if (wc->level == 1 &&
5114 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5115 continue;
5116 if (!wc->update_ref ||
5117 generation <= root->root_key.offset)
5118 continue;
5119 btrfs_node_key_to_cpu(eb, &key, slot);
5120 ret = btrfs_comp_cpu_keys(&key,
5121 &wc->update_progress);
5122 if (ret < 0)
5123 continue;
5124 } else {
5125 if (wc->level == 1 &&
5126 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5127 continue;
5128 }
5129 reada:
5130 btrfs_readahead_node_child(eb, slot);
5131 nread++;
5132 }
5133 wc->reada_slot = slot;
5134 }
5135
5136 /*
5137 * helper to process tree block while walking down the tree.
5138 *
5139 * when wc->stage == UPDATE_BACKREF, this function updates
5140 * back refs for pointers in the block.
5141 *
5142 * NOTE: return value 1 means we should stop walking down.
5143 */
walk_down_proc(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct walk_control * wc,int lookup_info)5144 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5145 struct btrfs_root *root,
5146 struct btrfs_path *path,
5147 struct walk_control *wc, int lookup_info)
5148 {
5149 struct btrfs_fs_info *fs_info = root->fs_info;
5150 int level = wc->level;
5151 struct extent_buffer *eb = path->nodes[level];
5152 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5153 int ret;
5154
5155 if (wc->stage == UPDATE_BACKREF &&
5156 btrfs_header_owner(eb) != root->root_key.objectid)
5157 return 1;
5158
5159 /*
5160 * when reference count of tree block is 1, it won't increase
5161 * again. once full backref flag is set, we never clear it.
5162 */
5163 if (lookup_info &&
5164 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5165 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5166 BUG_ON(!path->locks[level]);
5167 ret = btrfs_lookup_extent_info(trans, fs_info,
5168 eb->start, level, 1,
5169 &wc->refs[level],
5170 &wc->flags[level]);
5171 BUG_ON(ret == -ENOMEM);
5172 if (ret)
5173 return ret;
5174 BUG_ON(wc->refs[level] == 0);
5175 }
5176
5177 if (wc->stage == DROP_REFERENCE) {
5178 if (wc->refs[level] > 1)
5179 return 1;
5180
5181 if (path->locks[level] && !wc->keep_locks) {
5182 btrfs_tree_unlock_rw(eb, path->locks[level]);
5183 path->locks[level] = 0;
5184 }
5185 return 0;
5186 }
5187
5188 /* wc->stage == UPDATE_BACKREF */
5189 if (!(wc->flags[level] & flag)) {
5190 BUG_ON(!path->locks[level]);
5191 ret = btrfs_inc_ref(trans, root, eb, 1);
5192 BUG_ON(ret); /* -ENOMEM */
5193 ret = btrfs_dec_ref(trans, root, eb, 0);
5194 BUG_ON(ret); /* -ENOMEM */
5195 ret = btrfs_set_disk_extent_flags(trans, eb, flag,
5196 btrfs_header_level(eb));
5197 BUG_ON(ret); /* -ENOMEM */
5198 wc->flags[level] |= flag;
5199 }
5200
5201 /*
5202 * the block is shared by multiple trees, so it's not good to
5203 * keep the tree lock
5204 */
5205 if (path->locks[level] && level > 0) {
5206 btrfs_tree_unlock_rw(eb, path->locks[level]);
5207 path->locks[level] = 0;
5208 }
5209 return 0;
5210 }
5211
5212 /*
5213 * This is used to verify a ref exists for this root to deal with a bug where we
5214 * would have a drop_progress key that hadn't been updated properly.
5215 */
check_ref_exists(struct btrfs_trans_handle * trans,struct btrfs_root * root,u64 bytenr,u64 parent,int level)5216 static int check_ref_exists(struct btrfs_trans_handle *trans,
5217 struct btrfs_root *root, u64 bytenr, u64 parent,
5218 int level)
5219 {
5220 struct btrfs_path *path;
5221 struct btrfs_extent_inline_ref *iref;
5222 int ret;
5223
5224 path = btrfs_alloc_path();
5225 if (!path)
5226 return -ENOMEM;
5227
5228 ret = lookup_extent_backref(trans, path, &iref, bytenr,
5229 root->fs_info->nodesize, parent,
5230 root->root_key.objectid, level, 0);
5231 btrfs_free_path(path);
5232 if (ret == -ENOENT)
5233 return 0;
5234 if (ret < 0)
5235 return ret;
5236 return 1;
5237 }
5238
5239 /*
5240 * helper to process tree block pointer.
5241 *
5242 * when wc->stage == DROP_REFERENCE, this function checks
5243 * reference count of the block pointed to. if the block
5244 * is shared and we need update back refs for the subtree
5245 * rooted at the block, this function changes wc->stage to
5246 * UPDATE_BACKREF. if the block is shared and there is no
5247 * need to update back, this function drops the reference
5248 * to the block.
5249 *
5250 * NOTE: return value 1 means we should stop walking down.
5251 */
do_walk_down(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct walk_control * wc,int * lookup_info)5252 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5253 struct btrfs_root *root,
5254 struct btrfs_path *path,
5255 struct walk_control *wc, int *lookup_info)
5256 {
5257 struct btrfs_fs_info *fs_info = root->fs_info;
5258 u64 bytenr;
5259 u64 generation;
5260 u64 parent;
5261 struct btrfs_key key;
5262 struct btrfs_key first_key;
5263 struct btrfs_ref ref = { 0 };
5264 struct extent_buffer *next;
5265 int level = wc->level;
5266 int reada = 0;
5267 int ret = 0;
5268 bool need_account = false;
5269
5270 generation = btrfs_node_ptr_generation(path->nodes[level],
5271 path->slots[level]);
5272 /*
5273 * if the lower level block was created before the snapshot
5274 * was created, we know there is no need to update back refs
5275 * for the subtree
5276 */
5277 if (wc->stage == UPDATE_BACKREF &&
5278 generation <= root->root_key.offset) {
5279 *lookup_info = 1;
5280 return 1;
5281 }
5282
5283 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5284 btrfs_node_key_to_cpu(path->nodes[level], &first_key,
5285 path->slots[level]);
5286
5287 next = find_extent_buffer(fs_info, bytenr);
5288 if (!next) {
5289 next = btrfs_find_create_tree_block(fs_info, bytenr,
5290 root->root_key.objectid, level - 1);
5291 if (IS_ERR(next))
5292 return PTR_ERR(next);
5293 reada = 1;
5294 }
5295 btrfs_tree_lock(next);
5296
5297 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1,
5298 &wc->refs[level - 1],
5299 &wc->flags[level - 1]);
5300 if (ret < 0)
5301 goto out_unlock;
5302
5303 if (unlikely(wc->refs[level - 1] == 0)) {
5304 btrfs_err(fs_info, "Missing references.");
5305 ret = -EIO;
5306 goto out_unlock;
5307 }
5308 *lookup_info = 0;
5309
5310 if (wc->stage == DROP_REFERENCE) {
5311 if (wc->refs[level - 1] > 1) {
5312 need_account = true;
5313 if (level == 1 &&
5314 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5315 goto skip;
5316
5317 if (!wc->update_ref ||
5318 generation <= root->root_key.offset)
5319 goto skip;
5320
5321 btrfs_node_key_to_cpu(path->nodes[level], &key,
5322 path->slots[level]);
5323 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5324 if (ret < 0)
5325 goto skip;
5326
5327 wc->stage = UPDATE_BACKREF;
5328 wc->shared_level = level - 1;
5329 }
5330 } else {
5331 if (level == 1 &&
5332 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5333 goto skip;
5334 }
5335
5336 if (!btrfs_buffer_uptodate(next, generation, 0)) {
5337 btrfs_tree_unlock(next);
5338 free_extent_buffer(next);
5339 next = NULL;
5340 *lookup_info = 1;
5341 }
5342
5343 if (!next) {
5344 if (reada && level == 1)
5345 reada_walk_down(trans, root, wc, path);
5346 next = read_tree_block(fs_info, bytenr, root->root_key.objectid,
5347 generation, level - 1, &first_key);
5348 if (IS_ERR(next)) {
5349 return PTR_ERR(next);
5350 } else if (!extent_buffer_uptodate(next)) {
5351 free_extent_buffer(next);
5352 return -EIO;
5353 }
5354 btrfs_tree_lock(next);
5355 }
5356
5357 level--;
5358 ASSERT(level == btrfs_header_level(next));
5359 if (level != btrfs_header_level(next)) {
5360 btrfs_err(root->fs_info, "mismatched level");
5361 ret = -EIO;
5362 goto out_unlock;
5363 }
5364 path->nodes[level] = next;
5365 path->slots[level] = 0;
5366 path->locks[level] = BTRFS_WRITE_LOCK;
5367 wc->level = level;
5368 if (wc->level == 1)
5369 wc->reada_slot = 0;
5370 return 0;
5371 skip:
5372 wc->refs[level - 1] = 0;
5373 wc->flags[level - 1] = 0;
5374 if (wc->stage == DROP_REFERENCE) {
5375 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5376 parent = path->nodes[level]->start;
5377 } else {
5378 ASSERT(root->root_key.objectid ==
5379 btrfs_header_owner(path->nodes[level]));
5380 if (root->root_key.objectid !=
5381 btrfs_header_owner(path->nodes[level])) {
5382 btrfs_err(root->fs_info,
5383 "mismatched block owner");
5384 ret = -EIO;
5385 goto out_unlock;
5386 }
5387 parent = 0;
5388 }
5389
5390 /*
5391 * If we had a drop_progress we need to verify the refs are set
5392 * as expected. If we find our ref then we know that from here
5393 * on out everything should be correct, and we can clear the
5394 * ->restarted flag.
5395 */
5396 if (wc->restarted) {
5397 ret = check_ref_exists(trans, root, bytenr, parent,
5398 level - 1);
5399 if (ret < 0)
5400 goto out_unlock;
5401 if (ret == 0)
5402 goto no_delete;
5403 ret = 0;
5404 wc->restarted = 0;
5405 }
5406
5407 /*
5408 * Reloc tree doesn't contribute to qgroup numbers, and we have
5409 * already accounted them at merge time (replace_path),
5410 * thus we could skip expensive subtree trace here.
5411 */
5412 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
5413 need_account) {
5414 ret = btrfs_qgroup_trace_subtree(trans, next,
5415 generation, level - 1);
5416 if (ret) {
5417 btrfs_err_rl(fs_info,
5418 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
5419 ret);
5420 }
5421 }
5422
5423 /*
5424 * We need to update the next key in our walk control so we can
5425 * update the drop_progress key accordingly. We don't care if
5426 * find_next_key doesn't find a key because that means we're at
5427 * the end and are going to clean up now.
5428 */
5429 wc->drop_level = level;
5430 find_next_key(path, level, &wc->drop_progress);
5431
5432 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
5433 fs_info->nodesize, parent);
5434 btrfs_init_tree_ref(&ref, level - 1, root->root_key.objectid,
5435 0, false);
5436 ret = btrfs_free_extent(trans, &ref);
5437 if (ret)
5438 goto out_unlock;
5439 }
5440 no_delete:
5441 *lookup_info = 1;
5442 ret = 1;
5443
5444 out_unlock:
5445 btrfs_tree_unlock(next);
5446 free_extent_buffer(next);
5447
5448 return ret;
5449 }
5450
5451 /*
5452 * helper to process tree block while walking up the tree.
5453 *
5454 * when wc->stage == DROP_REFERENCE, this function drops
5455 * reference count on the block.
5456 *
5457 * when wc->stage == UPDATE_BACKREF, this function changes
5458 * wc->stage back to DROP_REFERENCE if we changed wc->stage
5459 * to UPDATE_BACKREF previously while processing the block.
5460 *
5461 * NOTE: return value 1 means we should stop walking up.
5462 */
walk_up_proc(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct walk_control * wc)5463 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
5464 struct btrfs_root *root,
5465 struct btrfs_path *path,
5466 struct walk_control *wc)
5467 {
5468 struct btrfs_fs_info *fs_info = root->fs_info;
5469 int ret;
5470 int level = wc->level;
5471 struct extent_buffer *eb = path->nodes[level];
5472 u64 parent = 0;
5473
5474 if (wc->stage == UPDATE_BACKREF) {
5475 BUG_ON(wc->shared_level < level);
5476 if (level < wc->shared_level)
5477 goto out;
5478
5479 ret = find_next_key(path, level + 1, &wc->update_progress);
5480 if (ret > 0)
5481 wc->update_ref = 0;
5482
5483 wc->stage = DROP_REFERENCE;
5484 wc->shared_level = -1;
5485 path->slots[level] = 0;
5486
5487 /*
5488 * check reference count again if the block isn't locked.
5489 * we should start walking down the tree again if reference
5490 * count is one.
5491 */
5492 if (!path->locks[level]) {
5493 BUG_ON(level == 0);
5494 btrfs_tree_lock(eb);
5495 path->locks[level] = BTRFS_WRITE_LOCK;
5496
5497 ret = btrfs_lookup_extent_info(trans, fs_info,
5498 eb->start, level, 1,
5499 &wc->refs[level],
5500 &wc->flags[level]);
5501 if (ret < 0) {
5502 btrfs_tree_unlock_rw(eb, path->locks[level]);
5503 path->locks[level] = 0;
5504 return ret;
5505 }
5506 BUG_ON(wc->refs[level] == 0);
5507 if (wc->refs[level] == 1) {
5508 btrfs_tree_unlock_rw(eb, path->locks[level]);
5509 path->locks[level] = 0;
5510 return 1;
5511 }
5512 }
5513 }
5514
5515 /* wc->stage == DROP_REFERENCE */
5516 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
5517
5518 if (wc->refs[level] == 1) {
5519 if (level == 0) {
5520 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5521 ret = btrfs_dec_ref(trans, root, eb, 1);
5522 else
5523 ret = btrfs_dec_ref(trans, root, eb, 0);
5524 BUG_ON(ret); /* -ENOMEM */
5525 if (is_fstree(root->root_key.objectid)) {
5526 ret = btrfs_qgroup_trace_leaf_items(trans, eb);
5527 if (ret) {
5528 btrfs_err_rl(fs_info,
5529 "error %d accounting leaf items, quota is out of sync, rescan required",
5530 ret);
5531 }
5532 }
5533 }
5534 /* make block locked assertion in btrfs_clean_tree_block happy */
5535 if (!path->locks[level] &&
5536 btrfs_header_generation(eb) == trans->transid) {
5537 btrfs_tree_lock(eb);
5538 path->locks[level] = BTRFS_WRITE_LOCK;
5539 }
5540 btrfs_clean_tree_block(eb);
5541 }
5542
5543 if (eb == root->node) {
5544 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5545 parent = eb->start;
5546 else if (root->root_key.objectid != btrfs_header_owner(eb))
5547 goto owner_mismatch;
5548 } else {
5549 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5550 parent = path->nodes[level + 1]->start;
5551 else if (root->root_key.objectid !=
5552 btrfs_header_owner(path->nodes[level + 1]))
5553 goto owner_mismatch;
5554 }
5555
5556 btrfs_free_tree_block(trans, btrfs_root_id(root), eb, parent,
5557 wc->refs[level] == 1);
5558 out:
5559 wc->refs[level] = 0;
5560 wc->flags[level] = 0;
5561 return 0;
5562
5563 owner_mismatch:
5564 btrfs_err_rl(fs_info, "unexpected tree owner, have %llu expect %llu",
5565 btrfs_header_owner(eb), root->root_key.objectid);
5566 return -EUCLEAN;
5567 }
5568
walk_down_tree(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct walk_control * wc)5569 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
5570 struct btrfs_root *root,
5571 struct btrfs_path *path,
5572 struct walk_control *wc)
5573 {
5574 int level = wc->level;
5575 int lookup_info = 1;
5576 int ret;
5577
5578 while (level >= 0) {
5579 ret = walk_down_proc(trans, root, path, wc, lookup_info);
5580 if (ret > 0)
5581 break;
5582
5583 if (level == 0)
5584 break;
5585
5586 if (path->slots[level] >=
5587 btrfs_header_nritems(path->nodes[level]))
5588 break;
5589
5590 ret = do_walk_down(trans, root, path, wc, &lookup_info);
5591 if (ret > 0) {
5592 path->slots[level]++;
5593 continue;
5594 } else if (ret < 0)
5595 return ret;
5596 level = wc->level;
5597 }
5598 return 0;
5599 }
5600
walk_up_tree(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct walk_control * wc,int max_level)5601 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
5602 struct btrfs_root *root,
5603 struct btrfs_path *path,
5604 struct walk_control *wc, int max_level)
5605 {
5606 int level = wc->level;
5607 int ret;
5608
5609 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
5610 while (level < max_level && path->nodes[level]) {
5611 wc->level = level;
5612 if (path->slots[level] + 1 <
5613 btrfs_header_nritems(path->nodes[level])) {
5614 path->slots[level]++;
5615 return 0;
5616 } else {
5617 ret = walk_up_proc(trans, root, path, wc);
5618 if (ret > 0)
5619 return 0;
5620 if (ret < 0)
5621 return ret;
5622
5623 if (path->locks[level]) {
5624 btrfs_tree_unlock_rw(path->nodes[level],
5625 path->locks[level]);
5626 path->locks[level] = 0;
5627 }
5628 free_extent_buffer(path->nodes[level]);
5629 path->nodes[level] = NULL;
5630 level++;
5631 }
5632 }
5633 return 1;
5634 }
5635
5636 /*
5637 * drop a subvolume tree.
5638 *
5639 * this function traverses the tree freeing any blocks that only
5640 * referenced by the tree.
5641 *
5642 * when a shared tree block is found. this function decreases its
5643 * reference count by one. if update_ref is true, this function
5644 * also make sure backrefs for the shared block and all lower level
5645 * blocks are properly updated.
5646 *
5647 * If called with for_reloc == 0, may exit early with -EAGAIN
5648 */
btrfs_drop_snapshot(struct btrfs_root * root,int update_ref,int for_reloc)5649 int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
5650 {
5651 const bool is_reloc_root = (root->root_key.objectid ==
5652 BTRFS_TREE_RELOC_OBJECTID);
5653 struct btrfs_fs_info *fs_info = root->fs_info;
5654 struct btrfs_path *path;
5655 struct btrfs_trans_handle *trans;
5656 struct btrfs_root *tree_root = fs_info->tree_root;
5657 struct btrfs_root_item *root_item = &root->root_item;
5658 struct walk_control *wc;
5659 struct btrfs_key key;
5660 int err = 0;
5661 int ret;
5662 int level;
5663 bool root_dropped = false;
5664 bool unfinished_drop = false;
5665
5666 btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
5667
5668 path = btrfs_alloc_path();
5669 if (!path) {
5670 err = -ENOMEM;
5671 goto out;
5672 }
5673
5674 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5675 if (!wc) {
5676 btrfs_free_path(path);
5677 err = -ENOMEM;
5678 goto out;
5679 }
5680
5681 /*
5682 * Use join to avoid potential EINTR from transaction start. See
5683 * wait_reserve_ticket and the whole reservation callchain.
5684 */
5685 if (for_reloc)
5686 trans = btrfs_join_transaction(tree_root);
5687 else
5688 trans = btrfs_start_transaction(tree_root, 0);
5689 if (IS_ERR(trans)) {
5690 err = PTR_ERR(trans);
5691 goto out_free;
5692 }
5693
5694 err = btrfs_run_delayed_items(trans);
5695 if (err)
5696 goto out_end_trans;
5697
5698 /*
5699 * This will help us catch people modifying the fs tree while we're
5700 * dropping it. It is unsafe to mess with the fs tree while it's being
5701 * dropped as we unlock the root node and parent nodes as we walk down
5702 * the tree, assuming nothing will change. If something does change
5703 * then we'll have stale information and drop references to blocks we've
5704 * already dropped.
5705 */
5706 set_bit(BTRFS_ROOT_DELETING, &root->state);
5707 unfinished_drop = test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state);
5708
5709 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
5710 level = btrfs_header_level(root->node);
5711 path->nodes[level] = btrfs_lock_root_node(root);
5712 path->slots[level] = 0;
5713 path->locks[level] = BTRFS_WRITE_LOCK;
5714 memset(&wc->update_progress, 0,
5715 sizeof(wc->update_progress));
5716 } else {
5717 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
5718 memcpy(&wc->update_progress, &key,
5719 sizeof(wc->update_progress));
5720
5721 level = btrfs_root_drop_level(root_item);
5722 BUG_ON(level == 0);
5723 path->lowest_level = level;
5724 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5725 path->lowest_level = 0;
5726 if (ret < 0) {
5727 err = ret;
5728 goto out_end_trans;
5729 }
5730 WARN_ON(ret > 0);
5731
5732 /*
5733 * unlock our path, this is safe because only this
5734 * function is allowed to delete this snapshot
5735 */
5736 btrfs_unlock_up_safe(path, 0);
5737
5738 level = btrfs_header_level(root->node);
5739 while (1) {
5740 btrfs_tree_lock(path->nodes[level]);
5741 path->locks[level] = BTRFS_WRITE_LOCK;
5742
5743 ret = btrfs_lookup_extent_info(trans, fs_info,
5744 path->nodes[level]->start,
5745 level, 1, &wc->refs[level],
5746 &wc->flags[level]);
5747 if (ret < 0) {
5748 err = ret;
5749 goto out_end_trans;
5750 }
5751 BUG_ON(wc->refs[level] == 0);
5752
5753 if (level == btrfs_root_drop_level(root_item))
5754 break;
5755
5756 btrfs_tree_unlock(path->nodes[level]);
5757 path->locks[level] = 0;
5758 WARN_ON(wc->refs[level] != 1);
5759 level--;
5760 }
5761 }
5762
5763 wc->restarted = test_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
5764 wc->level = level;
5765 wc->shared_level = -1;
5766 wc->stage = DROP_REFERENCE;
5767 wc->update_ref = update_ref;
5768 wc->keep_locks = 0;
5769 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
5770
5771 while (1) {
5772
5773 ret = walk_down_tree(trans, root, path, wc);
5774 if (ret < 0) {
5775 err = ret;
5776 break;
5777 }
5778
5779 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
5780 if (ret < 0) {
5781 err = ret;
5782 break;
5783 }
5784
5785 if (ret > 0) {
5786 BUG_ON(wc->stage != DROP_REFERENCE);
5787 break;
5788 }
5789
5790 if (wc->stage == DROP_REFERENCE) {
5791 wc->drop_level = wc->level;
5792 btrfs_node_key_to_cpu(path->nodes[wc->drop_level],
5793 &wc->drop_progress,
5794 path->slots[wc->drop_level]);
5795 }
5796 btrfs_cpu_key_to_disk(&root_item->drop_progress,
5797 &wc->drop_progress);
5798 btrfs_set_root_drop_level(root_item, wc->drop_level);
5799
5800 BUG_ON(wc->level == 0);
5801 if (btrfs_should_end_transaction(trans) ||
5802 (!for_reloc && btrfs_need_cleaner_sleep(fs_info))) {
5803 ret = btrfs_update_root(trans, tree_root,
5804 &root->root_key,
5805 root_item);
5806 if (ret) {
5807 btrfs_abort_transaction(trans, ret);
5808 err = ret;
5809 goto out_end_trans;
5810 }
5811
5812 if (!is_reloc_root)
5813 btrfs_set_last_root_drop_gen(fs_info, trans->transid);
5814
5815 btrfs_end_transaction_throttle(trans);
5816 if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) {
5817 btrfs_debug(fs_info,
5818 "drop snapshot early exit");
5819 err = -EAGAIN;
5820 goto out_free;
5821 }
5822
5823 /*
5824 * Use join to avoid potential EINTR from transaction
5825 * start. See wait_reserve_ticket and the whole
5826 * reservation callchain.
5827 */
5828 if (for_reloc)
5829 trans = btrfs_join_transaction(tree_root);
5830 else
5831 trans = btrfs_start_transaction(tree_root, 0);
5832 if (IS_ERR(trans)) {
5833 err = PTR_ERR(trans);
5834 goto out_free;
5835 }
5836 }
5837 }
5838 btrfs_release_path(path);
5839 if (err)
5840 goto out_end_trans;
5841
5842 ret = btrfs_del_root(trans, &root->root_key);
5843 if (ret) {
5844 btrfs_abort_transaction(trans, ret);
5845 err = ret;
5846 goto out_end_trans;
5847 }
5848
5849 if (!is_reloc_root) {
5850 ret = btrfs_find_root(tree_root, &root->root_key, path,
5851 NULL, NULL);
5852 if (ret < 0) {
5853 btrfs_abort_transaction(trans, ret);
5854 err = ret;
5855 goto out_end_trans;
5856 } else if (ret > 0) {
5857 /* if we fail to delete the orphan item this time
5858 * around, it'll get picked up the next time.
5859 *
5860 * The most common failure here is just -ENOENT.
5861 */
5862 btrfs_del_orphan_item(trans, tree_root,
5863 root->root_key.objectid);
5864 }
5865 }
5866
5867 /*
5868 * This subvolume is going to be completely dropped, and won't be
5869 * recorded as dirty roots, thus pertrans meta rsv will not be freed at
5870 * commit transaction time. So free it here manually.
5871 */
5872 btrfs_qgroup_convert_reserved_meta(root, INT_MAX);
5873 btrfs_qgroup_free_meta_all_pertrans(root);
5874
5875 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state))
5876 btrfs_add_dropped_root(trans, root);
5877 else
5878 btrfs_put_root(root);
5879 root_dropped = true;
5880 out_end_trans:
5881 if (!is_reloc_root)
5882 btrfs_set_last_root_drop_gen(fs_info, trans->transid);
5883
5884 btrfs_end_transaction_throttle(trans);
5885 out_free:
5886 kfree(wc);
5887 btrfs_free_path(path);
5888 out:
5889 /*
5890 * We were an unfinished drop root, check to see if there are any
5891 * pending, and if not clear and wake up any waiters.
5892 */
5893 if (!err && unfinished_drop)
5894 btrfs_maybe_wake_unfinished_drop(fs_info);
5895
5896 /*
5897 * So if we need to stop dropping the snapshot for whatever reason we
5898 * need to make sure to add it back to the dead root list so that we
5899 * keep trying to do the work later. This also cleans up roots if we
5900 * don't have it in the radix (like when we recover after a power fail
5901 * or unmount) so we don't leak memory.
5902 */
5903 if (!for_reloc && !root_dropped)
5904 btrfs_add_dead_root(root);
5905 return err;
5906 }
5907
5908 /*
5909 * drop subtree rooted at tree block 'node'.
5910 *
5911 * NOTE: this function will unlock and release tree block 'node'
5912 * only used by relocation code
5913 */
btrfs_drop_subtree(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct extent_buffer * node,struct extent_buffer * parent)5914 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
5915 struct btrfs_root *root,
5916 struct extent_buffer *node,
5917 struct extent_buffer *parent)
5918 {
5919 struct btrfs_fs_info *fs_info = root->fs_info;
5920 struct btrfs_path *path;
5921 struct walk_control *wc;
5922 int level;
5923 int parent_level;
5924 int ret = 0;
5925 int wret;
5926
5927 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5928
5929 path = btrfs_alloc_path();
5930 if (!path)
5931 return -ENOMEM;
5932
5933 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5934 if (!wc) {
5935 btrfs_free_path(path);
5936 return -ENOMEM;
5937 }
5938
5939 btrfs_assert_tree_write_locked(parent);
5940 parent_level = btrfs_header_level(parent);
5941 atomic_inc(&parent->refs);
5942 path->nodes[parent_level] = parent;
5943 path->slots[parent_level] = btrfs_header_nritems(parent);
5944
5945 btrfs_assert_tree_write_locked(node);
5946 level = btrfs_header_level(node);
5947 path->nodes[level] = node;
5948 path->slots[level] = 0;
5949 path->locks[level] = BTRFS_WRITE_LOCK;
5950
5951 wc->refs[parent_level] = 1;
5952 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5953 wc->level = level;
5954 wc->shared_level = -1;
5955 wc->stage = DROP_REFERENCE;
5956 wc->update_ref = 0;
5957 wc->keep_locks = 1;
5958 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
5959
5960 while (1) {
5961 wret = walk_down_tree(trans, root, path, wc);
5962 if (wret < 0) {
5963 ret = wret;
5964 break;
5965 }
5966
5967 wret = walk_up_tree(trans, root, path, wc, parent_level);
5968 if (wret < 0)
5969 ret = wret;
5970 if (wret != 0)
5971 break;
5972 }
5973
5974 kfree(wc);
5975 btrfs_free_path(path);
5976 return ret;
5977 }
5978
5979 /*
5980 * helper to account the unused space of all the readonly block group in the
5981 * space_info. takes mirrors into account.
5982 */
btrfs_account_ro_block_groups_free_space(struct btrfs_space_info * sinfo)5983 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
5984 {
5985 struct btrfs_block_group *block_group;
5986 u64 free_bytes = 0;
5987 int factor;
5988
5989 /* It's df, we don't care if it's racy */
5990 if (list_empty(&sinfo->ro_bgs))
5991 return 0;
5992
5993 spin_lock(&sinfo->lock);
5994 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
5995 spin_lock(&block_group->lock);
5996
5997 if (!block_group->ro) {
5998 spin_unlock(&block_group->lock);
5999 continue;
6000 }
6001
6002 factor = btrfs_bg_type_to_factor(block_group->flags);
6003 free_bytes += (block_group->length -
6004 block_group->used) * factor;
6005
6006 spin_unlock(&block_group->lock);
6007 }
6008 spin_unlock(&sinfo->lock);
6009
6010 return free_bytes;
6011 }
6012
btrfs_error_unpin_extent_range(struct btrfs_fs_info * fs_info,u64 start,u64 end)6013 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
6014 u64 start, u64 end)
6015 {
6016 return unpin_extent_range(fs_info, start, end, false);
6017 }
6018
6019 /*
6020 * It used to be that old block groups would be left around forever.
6021 * Iterating over them would be enough to trim unused space. Since we
6022 * now automatically remove them, we also need to iterate over unallocated
6023 * space.
6024 *
6025 * We don't want a transaction for this since the discard may take a
6026 * substantial amount of time. We don't require that a transaction be
6027 * running, but we do need to take a running transaction into account
6028 * to ensure that we're not discarding chunks that were released or
6029 * allocated in the current transaction.
6030 *
6031 * Holding the chunks lock will prevent other threads from allocating
6032 * or releasing chunks, but it won't prevent a running transaction
6033 * from committing and releasing the memory that the pending chunks
6034 * list head uses. For that, we need to take a reference to the
6035 * transaction and hold the commit root sem. We only need to hold
6036 * it while performing the free space search since we have already
6037 * held back allocations.
6038 */
btrfs_trim_free_extents(struct btrfs_device * device,u64 * trimmed)6039 static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed)
6040 {
6041 u64 start = BTRFS_DEVICE_RANGE_RESERVED, len = 0, end = 0;
6042 int ret;
6043
6044 *trimmed = 0;
6045
6046 /* Discard not supported = nothing to do. */
6047 if (!bdev_max_discard_sectors(device->bdev))
6048 return 0;
6049
6050 /* Not writable = nothing to do. */
6051 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
6052 return 0;
6053
6054 /* No free space = nothing to do. */
6055 if (device->total_bytes <= device->bytes_used)
6056 return 0;
6057
6058 ret = 0;
6059
6060 while (1) {
6061 struct btrfs_fs_info *fs_info = device->fs_info;
6062 u64 bytes;
6063
6064 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
6065 if (ret)
6066 break;
6067
6068 find_first_clear_extent_bit(&device->alloc_state, start,
6069 &start, &end,
6070 CHUNK_TRIMMED | CHUNK_ALLOCATED);
6071
6072 /* Check if there are any CHUNK_* bits left */
6073 if (start > device->total_bytes) {
6074 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
6075 btrfs_warn_in_rcu(fs_info,
6076 "ignoring attempt to trim beyond device size: offset %llu length %llu device %s device size %llu",
6077 start, end - start + 1,
6078 rcu_str_deref(device->name),
6079 device->total_bytes);
6080 mutex_unlock(&fs_info->chunk_mutex);
6081 ret = 0;
6082 break;
6083 }
6084
6085 /* Ensure we skip the reserved space on each device. */
6086 start = max_t(u64, start, BTRFS_DEVICE_RANGE_RESERVED);
6087
6088 /*
6089 * If find_first_clear_extent_bit find a range that spans the
6090 * end of the device it will set end to -1, in this case it's up
6091 * to the caller to trim the value to the size of the device.
6092 */
6093 end = min(end, device->total_bytes - 1);
6094
6095 len = end - start + 1;
6096
6097 /* We didn't find any extents */
6098 if (!len) {
6099 mutex_unlock(&fs_info->chunk_mutex);
6100 ret = 0;
6101 break;
6102 }
6103
6104 ret = btrfs_issue_discard(device->bdev, start, len,
6105 &bytes);
6106 if (!ret)
6107 set_extent_bits(&device->alloc_state, start,
6108 start + bytes - 1,
6109 CHUNK_TRIMMED);
6110 mutex_unlock(&fs_info->chunk_mutex);
6111
6112 if (ret)
6113 break;
6114
6115 start += len;
6116 *trimmed += bytes;
6117
6118 if (fatal_signal_pending(current)) {
6119 ret = -ERESTARTSYS;
6120 break;
6121 }
6122
6123 cond_resched();
6124 }
6125
6126 return ret;
6127 }
6128
6129 /*
6130 * Trim the whole filesystem by:
6131 * 1) trimming the free space in each block group
6132 * 2) trimming the unallocated space on each device
6133 *
6134 * This will also continue trimming even if a block group or device encounters
6135 * an error. The return value will be the last error, or 0 if nothing bad
6136 * happens.
6137 */
btrfs_trim_fs(struct btrfs_fs_info * fs_info,struct fstrim_range * range)6138 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
6139 {
6140 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6141 struct btrfs_block_group *cache = NULL;
6142 struct btrfs_device *device;
6143 u64 group_trimmed;
6144 u64 range_end = U64_MAX;
6145 u64 start;
6146 u64 end;
6147 u64 trimmed = 0;
6148 u64 bg_failed = 0;
6149 u64 dev_failed = 0;
6150 int bg_ret = 0;
6151 int dev_ret = 0;
6152 int ret = 0;
6153
6154 if (range->start == U64_MAX)
6155 return -EINVAL;
6156
6157 /*
6158 * Check range overflow if range->len is set.
6159 * The default range->len is U64_MAX.
6160 */
6161 if (range->len != U64_MAX &&
6162 check_add_overflow(range->start, range->len, &range_end))
6163 return -EINVAL;
6164
6165 cache = btrfs_lookup_first_block_group(fs_info, range->start);
6166 for (; cache; cache = btrfs_next_block_group(cache)) {
6167 if (cache->start >= range_end) {
6168 btrfs_put_block_group(cache);
6169 break;
6170 }
6171
6172 start = max(range->start, cache->start);
6173 end = min(range_end, cache->start + cache->length);
6174
6175 if (end - start >= range->minlen) {
6176 if (!btrfs_block_group_done(cache)) {
6177 ret = btrfs_cache_block_group(cache, true);
6178 if (ret) {
6179 bg_failed++;
6180 bg_ret = ret;
6181 continue;
6182 }
6183 }
6184 ret = btrfs_trim_block_group(cache,
6185 &group_trimmed,
6186 start,
6187 end,
6188 range->minlen);
6189
6190 trimmed += group_trimmed;
6191 if (ret) {
6192 bg_failed++;
6193 bg_ret = ret;
6194 continue;
6195 }
6196 }
6197 }
6198
6199 if (bg_failed)
6200 btrfs_warn(fs_info,
6201 "failed to trim %llu block group(s), last error %d",
6202 bg_failed, bg_ret);
6203
6204 mutex_lock(&fs_devices->device_list_mutex);
6205 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6206 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
6207 continue;
6208
6209 ret = btrfs_trim_free_extents(device, &group_trimmed);
6210 if (ret) {
6211 dev_failed++;
6212 dev_ret = ret;
6213 break;
6214 }
6215
6216 trimmed += group_trimmed;
6217 }
6218 mutex_unlock(&fs_devices->device_list_mutex);
6219
6220 if (dev_failed)
6221 btrfs_warn(fs_info,
6222 "failed to trim %llu device(s), last error %d",
6223 dev_failed, dev_ret);
6224 range->len = trimmed;
6225 if (bg_ret)
6226 return bg_ret;
6227 return dev_ret;
6228 }
6229