1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include "ctree.h"
7 #include "fs.h"
8 #include "messages.h"
9 #include "inode-item.h"
10 #include "disk-io.h"
11 #include "transaction.h"
12 #include "space-info.h"
13 #include "accessors.h"
14 #include "extent-tree.h"
15 #include "file-item.h"
16
btrfs_find_name_in_backref(const struct extent_buffer * leaf,int slot,const struct fscrypt_str * name)17 struct btrfs_inode_ref *btrfs_find_name_in_backref(const struct extent_buffer *leaf,
18 int slot,
19 const struct fscrypt_str *name)
20 {
21 struct btrfs_inode_ref *ref;
22 unsigned long ptr;
23 unsigned long name_ptr;
24 u32 item_size;
25 u32 cur_offset = 0;
26 int len;
27
28 item_size = btrfs_item_size(leaf, slot);
29 ptr = btrfs_item_ptr_offset(leaf, slot);
30 while (cur_offset < item_size) {
31 ref = (struct btrfs_inode_ref *)(ptr + cur_offset);
32 len = btrfs_inode_ref_name_len(leaf, ref);
33 name_ptr = (unsigned long)(ref + 1);
34 cur_offset += len + sizeof(*ref);
35 if (len != name->len)
36 continue;
37 if (memcmp_extent_buffer(leaf, name->name, name_ptr,
38 name->len) == 0)
39 return ref;
40 }
41 return NULL;
42 }
43
btrfs_find_name_in_ext_backref(const struct extent_buffer * leaf,int slot,u64 ref_objectid,const struct fscrypt_str * name)44 struct btrfs_inode_extref *btrfs_find_name_in_ext_backref(
45 const struct extent_buffer *leaf, int slot, u64 ref_objectid,
46 const struct fscrypt_str *name)
47 {
48 struct btrfs_inode_extref *extref;
49 unsigned long ptr;
50 unsigned long name_ptr;
51 u32 item_size;
52 u32 cur_offset = 0;
53 int ref_name_len;
54
55 item_size = btrfs_item_size(leaf, slot);
56 ptr = btrfs_item_ptr_offset(leaf, slot);
57
58 /*
59 * Search all extended backrefs in this item. We're only
60 * looking through any collisions so most of the time this is
61 * just going to compare against one buffer. If all is well,
62 * we'll return success and the inode ref object.
63 */
64 while (cur_offset < item_size) {
65 extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
66 name_ptr = (unsigned long)(&extref->name);
67 ref_name_len = btrfs_inode_extref_name_len(leaf, extref);
68
69 if (ref_name_len == name->len &&
70 btrfs_inode_extref_parent(leaf, extref) == ref_objectid &&
71 (memcmp_extent_buffer(leaf, name->name, name_ptr,
72 name->len) == 0))
73 return extref;
74
75 cur_offset += ref_name_len + sizeof(*extref);
76 }
77 return NULL;
78 }
79
80 /* Returns NULL if no extref found */
btrfs_lookup_inode_extref(struct btrfs_root * root,struct btrfs_path * path,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid)81 struct btrfs_inode_extref *btrfs_lookup_inode_extref(struct btrfs_root *root,
82 struct btrfs_path *path,
83 const struct fscrypt_str *name,
84 u64 inode_objectid, u64 ref_objectid)
85 {
86 int ret;
87 struct btrfs_key key;
88
89 key.objectid = inode_objectid;
90 key.type = BTRFS_INODE_EXTREF_KEY;
91 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
92
93 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
94 if (ret < 0)
95 return ERR_PTR(ret);
96 if (ret > 0)
97 return NULL;
98 return btrfs_find_name_in_ext_backref(path->nodes[0], path->slots[0],
99 ref_objectid, name);
100
101 }
102
btrfs_del_inode_extref(struct btrfs_trans_handle * trans,struct btrfs_root * root,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid,u64 * index)103 static int btrfs_del_inode_extref(struct btrfs_trans_handle *trans,
104 struct btrfs_root *root,
105 const struct fscrypt_str *name,
106 u64 inode_objectid, u64 ref_objectid,
107 u64 *index)
108 {
109 BTRFS_PATH_AUTO_FREE(path);
110 struct btrfs_key key;
111 struct btrfs_inode_extref *extref;
112 struct extent_buffer *leaf;
113 int ret;
114 int del_len = name->len + sizeof(*extref);
115 unsigned long ptr;
116 unsigned long item_start;
117 u32 item_size;
118
119 key.objectid = inode_objectid;
120 key.type = BTRFS_INODE_EXTREF_KEY;
121 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
122
123 path = btrfs_alloc_path();
124 if (!path)
125 return -ENOMEM;
126
127 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
128 if (ret > 0)
129 return -ENOENT;
130 if (ret < 0)
131 return ret;
132
133 /*
134 * Sanity check - did we find the right item for this name?
135 * This should always succeed so error here will make the FS
136 * readonly.
137 */
138 extref = btrfs_find_name_in_ext_backref(path->nodes[0], path->slots[0],
139 ref_objectid, name);
140 if (!extref) {
141 btrfs_abort_transaction(trans, -ENOENT);
142 return -ENOENT;
143 }
144
145 leaf = path->nodes[0];
146 item_size = btrfs_item_size(leaf, path->slots[0]);
147 if (index)
148 *index = btrfs_inode_extref_index(leaf, extref);
149
150 if (del_len == item_size) {
151 /* Common case only one ref in the item, remove the whole item. */
152 return btrfs_del_item(trans, root, path);
153 }
154
155 ptr = (unsigned long)extref;
156 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
157
158 memmove_extent_buffer(leaf, ptr, ptr + del_len,
159 item_size - (ptr + del_len - item_start));
160
161 btrfs_truncate_item(trans, path, item_size - del_len, 1);
162
163 return ret;
164 }
165
btrfs_del_inode_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid,u64 * index)166 int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
167 struct btrfs_root *root, const struct fscrypt_str *name,
168 u64 inode_objectid, u64 ref_objectid, u64 *index)
169 {
170 struct btrfs_path *path;
171 struct btrfs_key key;
172 struct btrfs_inode_ref *ref;
173 struct extent_buffer *leaf;
174 unsigned long ptr;
175 unsigned long item_start;
176 u32 item_size;
177 u32 sub_item_len;
178 int ret;
179 int search_ext_refs = 0;
180 int del_len = name->len + sizeof(*ref);
181
182 key.objectid = inode_objectid;
183 key.type = BTRFS_INODE_REF_KEY;
184 key.offset = ref_objectid;
185
186 path = btrfs_alloc_path();
187 if (!path)
188 return -ENOMEM;
189
190 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
191 if (ret > 0) {
192 ret = -ENOENT;
193 search_ext_refs = 1;
194 goto out;
195 } else if (ret < 0) {
196 goto out;
197 }
198
199 ref = btrfs_find_name_in_backref(path->nodes[0], path->slots[0], name);
200 if (!ref) {
201 ret = -ENOENT;
202 search_ext_refs = 1;
203 goto out;
204 }
205 leaf = path->nodes[0];
206 item_size = btrfs_item_size(leaf, path->slots[0]);
207
208 if (index)
209 *index = btrfs_inode_ref_index(leaf, ref);
210
211 if (del_len == item_size) {
212 ret = btrfs_del_item(trans, root, path);
213 goto out;
214 }
215 ptr = (unsigned long)ref;
216 sub_item_len = name->len + sizeof(*ref);
217 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
218 memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
219 item_size - (ptr + sub_item_len - item_start));
220 btrfs_truncate_item(trans, path, item_size - sub_item_len, 1);
221 out:
222 btrfs_free_path(path);
223
224 if (search_ext_refs) {
225 /*
226 * No refs were found, or we could not find the
227 * name in our ref array. Find and remove the extended
228 * inode ref then.
229 */
230 return btrfs_del_inode_extref(trans, root, name,
231 inode_objectid, ref_objectid, index);
232 }
233
234 return ret;
235 }
236
237 /*
238 * Insert an extended inode ref into a tree.
239 *
240 * The caller must have checked against BTRFS_LINK_MAX already.
241 */
btrfs_insert_inode_extref(struct btrfs_trans_handle * trans,struct btrfs_root * root,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid,u64 index)242 static int btrfs_insert_inode_extref(struct btrfs_trans_handle *trans,
243 struct btrfs_root *root,
244 const struct fscrypt_str *name,
245 u64 inode_objectid, u64 ref_objectid,
246 u64 index)
247 {
248 struct btrfs_inode_extref *extref;
249 int ret;
250 int ins_len = name->len + sizeof(*extref);
251 unsigned long ptr;
252 BTRFS_PATH_AUTO_FREE(path);
253 struct btrfs_key key;
254 struct extent_buffer *leaf;
255
256 key.objectid = inode_objectid;
257 key.type = BTRFS_INODE_EXTREF_KEY;
258 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
259
260 path = btrfs_alloc_path();
261 if (!path)
262 return -ENOMEM;
263
264 ret = btrfs_insert_empty_item(trans, root, path, &key,
265 ins_len);
266 if (ret == -EEXIST) {
267 if (btrfs_find_name_in_ext_backref(path->nodes[0],
268 path->slots[0],
269 ref_objectid,
270 name))
271 return ret;
272
273 btrfs_extend_item(trans, path, ins_len);
274 ret = 0;
275 }
276 if (ret < 0)
277 return ret;
278
279 leaf = path->nodes[0];
280 ptr = (unsigned long)btrfs_item_ptr(leaf, path->slots[0], char);
281 ptr += btrfs_item_size(leaf, path->slots[0]) - ins_len;
282 extref = (struct btrfs_inode_extref *)ptr;
283
284 btrfs_set_inode_extref_name_len(path->nodes[0], extref, name->len);
285 btrfs_set_inode_extref_index(path->nodes[0], extref, index);
286 btrfs_set_inode_extref_parent(path->nodes[0], extref, ref_objectid);
287
288 ptr = (unsigned long)&extref->name;
289 write_extent_buffer(path->nodes[0], name->name, ptr, name->len);
290
291 return 0;
292 }
293
294 /* Will return 0, -ENOMEM, -EMLINK, or -EEXIST or anything from the CoW path */
btrfs_insert_inode_ref(struct btrfs_trans_handle * trans,struct btrfs_root * root,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid,u64 index)295 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
296 struct btrfs_root *root, const struct fscrypt_str *name,
297 u64 inode_objectid, u64 ref_objectid, u64 index)
298 {
299 struct btrfs_fs_info *fs_info = root->fs_info;
300 struct btrfs_path *path;
301 struct btrfs_key key;
302 struct btrfs_inode_ref *ref;
303 unsigned long ptr;
304 int ret;
305 int ins_len = name->len + sizeof(*ref);
306
307 key.objectid = inode_objectid;
308 key.type = BTRFS_INODE_REF_KEY;
309 key.offset = ref_objectid;
310
311 path = btrfs_alloc_path();
312 if (!path)
313 return -ENOMEM;
314
315 path->skip_release_on_error = 1;
316 ret = btrfs_insert_empty_item(trans, root, path, &key,
317 ins_len);
318 if (ret == -EEXIST) {
319 u32 old_size;
320 ref = btrfs_find_name_in_backref(path->nodes[0], path->slots[0],
321 name);
322 if (ref)
323 goto out;
324
325 old_size = btrfs_item_size(path->nodes[0], path->slots[0]);
326 btrfs_extend_item(trans, path, ins_len);
327 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
328 struct btrfs_inode_ref);
329 ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
330 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name->len);
331 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
332 ptr = (unsigned long)(ref + 1);
333 ret = 0;
334 } else if (ret < 0) {
335 if (ret == -EOVERFLOW) {
336 if (btrfs_find_name_in_backref(path->nodes[0],
337 path->slots[0],
338 name))
339 ret = -EEXIST;
340 else
341 ret = -EMLINK;
342 }
343 goto out;
344 } else {
345 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
346 struct btrfs_inode_ref);
347 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name->len);
348 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
349 ptr = (unsigned long)(ref + 1);
350 }
351 write_extent_buffer(path->nodes[0], name->name, ptr, name->len);
352 out:
353 btrfs_free_path(path);
354
355 if (ret == -EMLINK) {
356 struct btrfs_super_block *disk_super = fs_info->super_copy;
357 /* We ran out of space in the ref array. Need to
358 * add an extended ref. */
359 if (btrfs_super_incompat_flags(disk_super)
360 & BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
361 ret = btrfs_insert_inode_extref(trans, root, name,
362 inode_objectid,
363 ref_objectid, index);
364 }
365
366 return ret;
367 }
368
btrfs_insert_empty_inode(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,u64 objectid)369 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
370 struct btrfs_root *root,
371 struct btrfs_path *path, u64 objectid)
372 {
373 struct btrfs_key key;
374 int ret;
375 key.objectid = objectid;
376 key.type = BTRFS_INODE_ITEM_KEY;
377 key.offset = 0;
378
379 ret = btrfs_insert_empty_item(trans, root, path, &key,
380 sizeof(struct btrfs_inode_item));
381 return ret;
382 }
383
btrfs_lookup_inode(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct btrfs_key * location,int mod)384 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
385 *root, struct btrfs_path *path,
386 struct btrfs_key *location, int mod)
387 {
388 int ins_len = mod < 0 ? -1 : 0;
389 int cow = mod != 0;
390 int ret;
391 int slot;
392 struct extent_buffer *leaf;
393 struct btrfs_key found_key;
394
395 ret = btrfs_search_slot(trans, root, location, path, ins_len, cow);
396 if (ret > 0 && location->type == BTRFS_ROOT_ITEM_KEY &&
397 location->offset == (u64)-1 && path->slots[0] != 0) {
398 slot = path->slots[0] - 1;
399 leaf = path->nodes[0];
400 btrfs_item_key_to_cpu(leaf, &found_key, slot);
401 if (found_key.objectid == location->objectid &&
402 found_key.type == location->type) {
403 path->slots[0]--;
404 return 0;
405 }
406 }
407 return ret;
408 }
409
btrfs_trace_truncate(const struct btrfs_inode * inode,const struct extent_buffer * leaf,const struct btrfs_file_extent_item * fi,u64 offset,int extent_type,int slot)410 static inline void btrfs_trace_truncate(const struct btrfs_inode *inode,
411 const struct extent_buffer *leaf,
412 const struct btrfs_file_extent_item *fi,
413 u64 offset, int extent_type, int slot)
414 {
415 if (!inode)
416 return;
417 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
418 trace_btrfs_truncate_show_fi_inline(inode, leaf, fi, slot,
419 offset);
420 else
421 trace_btrfs_truncate_show_fi_regular(inode, leaf, fi, offset);
422 }
423
424 /*
425 * Remove inode items from a given root.
426 *
427 * @trans: A transaction handle.
428 * @root: The root from which to remove items.
429 * @inode: The inode whose items we want to remove.
430 * @control: The btrfs_truncate_control to control how and what we
431 * are truncating.
432 *
433 * Remove all keys associated with the inode from the given root that have a key
434 * with a type greater than or equals to @min_type. When @min_type has a value of
435 * BTRFS_EXTENT_DATA_KEY, only remove file extent items that have an offset value
436 * greater than or equals to @new_size. If a file extent item that starts before
437 * @new_size and ends after it is found, its length is adjusted.
438 *
439 * Returns: 0 on success, < 0 on error and NEED_TRUNCATE_BLOCK when @min_type is
440 * BTRFS_EXTENT_DATA_KEY and the caller must truncate the last block.
441 */
btrfs_truncate_inode_items(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_truncate_control * control)442 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
443 struct btrfs_root *root,
444 struct btrfs_truncate_control *control)
445 {
446 struct btrfs_fs_info *fs_info = root->fs_info;
447 struct btrfs_path *path;
448 struct extent_buffer *leaf;
449 struct btrfs_file_extent_item *fi;
450 struct btrfs_key key;
451 struct btrfs_key found_key;
452 u64 new_size = control->new_size;
453 u64 extent_num_bytes = 0;
454 u64 extent_offset = 0;
455 u64 item_end = 0;
456 u32 found_type = (u8)-1;
457 int del_item;
458 int pending_del_nr = 0;
459 int pending_del_slot = 0;
460 int extent_type = -1;
461 int ret;
462 u64 bytes_deleted = 0;
463 bool be_nice = false;
464
465 ASSERT(control->inode || !control->clear_extent_range);
466 ASSERT(new_size == 0 || control->min_type == BTRFS_EXTENT_DATA_KEY);
467
468 control->last_size = new_size;
469 control->sub_bytes = 0;
470
471 /*
472 * For shareable roots we want to back off from time to time, this turns
473 * out to be subvolume roots, reloc roots, and data reloc roots.
474 */
475 if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
476 be_nice = true;
477
478 path = btrfs_alloc_path();
479 if (!path)
480 return -ENOMEM;
481 path->reada = READA_BACK;
482
483 key.objectid = control->ino;
484 key.type = (u8)-1;
485 key.offset = (u64)-1;
486
487 search_again:
488 /*
489 * With a 16K leaf size and 128MiB extents, you can actually queue up a
490 * huge file in a single leaf. Most of the time that bytes_deleted is
491 * > 0, it will be huge by the time we get here
492 */
493 if (be_nice && bytes_deleted > SZ_32M &&
494 btrfs_should_end_transaction(trans)) {
495 ret = -EAGAIN;
496 goto out;
497 }
498
499 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
500 if (ret < 0)
501 goto out;
502
503 if (ret > 0) {
504 ret = 0;
505 /* There are no items in the tree for us to truncate, we're done */
506 if (path->slots[0] == 0)
507 goto out;
508 path->slots[0]--;
509 }
510
511 while (1) {
512 u64 clear_start = 0, clear_len = 0, extent_start = 0;
513 bool refill_delayed_refs_rsv = false;
514
515 fi = NULL;
516 leaf = path->nodes[0];
517 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
518 found_type = found_key.type;
519
520 if (found_key.objectid != control->ino)
521 break;
522
523 if (found_type < control->min_type)
524 break;
525
526 item_end = found_key.offset;
527 if (found_type == BTRFS_EXTENT_DATA_KEY) {
528 fi = btrfs_item_ptr(leaf, path->slots[0],
529 struct btrfs_file_extent_item);
530 extent_type = btrfs_file_extent_type(leaf, fi);
531 if (extent_type != BTRFS_FILE_EXTENT_INLINE)
532 item_end +=
533 btrfs_file_extent_num_bytes(leaf, fi);
534 else if (extent_type == BTRFS_FILE_EXTENT_INLINE)
535 item_end += btrfs_file_extent_ram_bytes(leaf, fi);
536
537 btrfs_trace_truncate(control->inode, leaf, fi,
538 found_key.offset, extent_type,
539 path->slots[0]);
540 item_end--;
541 }
542 if (found_type > control->min_type) {
543 del_item = 1;
544 } else {
545 if (item_end < new_size)
546 break;
547 if (found_key.offset >= new_size)
548 del_item = 1;
549 else
550 del_item = 0;
551 }
552
553 /* FIXME, shrink the extent if the ref count is only 1 */
554 if (found_type != BTRFS_EXTENT_DATA_KEY)
555 goto delete;
556
557 control->extents_found++;
558
559 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
560 u64 num_dec;
561
562 clear_start = found_key.offset;
563 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
564 if (!del_item) {
565 u64 orig_num_bytes =
566 btrfs_file_extent_num_bytes(leaf, fi);
567 extent_num_bytes = ALIGN(new_size -
568 found_key.offset,
569 fs_info->sectorsize);
570 clear_start = ALIGN(new_size, fs_info->sectorsize);
571
572 btrfs_set_file_extent_num_bytes(leaf, fi,
573 extent_num_bytes);
574 num_dec = (orig_num_bytes - extent_num_bytes);
575 if (extent_start != 0)
576 control->sub_bytes += num_dec;
577 } else {
578 extent_num_bytes =
579 btrfs_file_extent_disk_num_bytes(leaf, fi);
580 extent_offset = found_key.offset -
581 btrfs_file_extent_offset(leaf, fi);
582
583 /* FIXME blocksize != 4096 */
584 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
585 if (extent_start != 0)
586 control->sub_bytes += num_dec;
587 }
588 clear_len = num_dec;
589 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
590 /*
591 * We can't truncate inline items that have had
592 * special encodings
593 */
594 if (!del_item &&
595 btrfs_file_extent_encryption(leaf, fi) == 0 &&
596 btrfs_file_extent_other_encoding(leaf, fi) == 0 &&
597 btrfs_file_extent_compression(leaf, fi) == 0) {
598 u32 size = (u32)(new_size - found_key.offset);
599
600 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
601 size = btrfs_file_extent_calc_inline_size(size);
602 btrfs_truncate_item(trans, path, size, 1);
603 } else if (!del_item) {
604 /*
605 * We have to bail so the last_size is set to
606 * just before this extent.
607 */
608 ret = BTRFS_NEED_TRUNCATE_BLOCK;
609 break;
610 } else {
611 /*
612 * Inline extents are special, we just treat
613 * them as a full sector worth in the file
614 * extent tree just for simplicity sake.
615 */
616 clear_len = fs_info->sectorsize;
617 }
618
619 control->sub_bytes += item_end + 1 - new_size;
620 }
621 delete:
622 /*
623 * We only want to clear the file extent range if we're
624 * modifying the actual inode's mapping, which is just the
625 * normal truncate path.
626 */
627 if (control->clear_extent_range) {
628 ret = btrfs_inode_clear_file_extent_range(control->inode,
629 clear_start, clear_len);
630 if (ret) {
631 btrfs_abort_transaction(trans, ret);
632 break;
633 }
634 }
635
636 if (del_item) {
637 ASSERT(!pending_del_nr ||
638 ((path->slots[0] + 1) == pending_del_slot));
639
640 control->last_size = found_key.offset;
641 if (!pending_del_nr) {
642 /* No pending yet, add ourselves */
643 pending_del_slot = path->slots[0];
644 pending_del_nr = 1;
645 } else if (path->slots[0] + 1 == pending_del_slot) {
646 /* Hop on the pending chunk */
647 pending_del_nr++;
648 pending_del_slot = path->slots[0];
649 }
650 } else {
651 control->last_size = new_size;
652 break;
653 }
654
655 if (del_item && extent_start != 0 && !control->skip_ref_updates) {
656 struct btrfs_ref ref = {
657 .action = BTRFS_DROP_DELAYED_REF,
658 .bytenr = extent_start,
659 .num_bytes = extent_num_bytes,
660 .owning_root = btrfs_root_id(root),
661 .ref_root = btrfs_header_owner(leaf),
662 };
663
664 bytes_deleted += extent_num_bytes;
665
666 btrfs_init_data_ref(&ref, control->ino, extent_offset,
667 btrfs_root_id(root), false);
668 ret = btrfs_free_extent(trans, &ref);
669 if (ret) {
670 btrfs_abort_transaction(trans, ret);
671 break;
672 }
673 if (be_nice && btrfs_check_space_for_delayed_refs(fs_info))
674 refill_delayed_refs_rsv = true;
675 }
676
677 if (found_type == BTRFS_INODE_ITEM_KEY)
678 break;
679
680 if (path->slots[0] == 0 ||
681 path->slots[0] != pending_del_slot ||
682 refill_delayed_refs_rsv) {
683 if (pending_del_nr) {
684 ret = btrfs_del_items(trans, root, path,
685 pending_del_slot,
686 pending_del_nr);
687 if (ret) {
688 btrfs_abort_transaction(trans, ret);
689 break;
690 }
691 pending_del_nr = 0;
692 }
693 btrfs_release_path(path);
694
695 /*
696 * We can generate a lot of delayed refs, so we need to
697 * throttle every once and a while and make sure we're
698 * adding enough space to keep up with the work we are
699 * generating. Since we hold a transaction here we
700 * can't flush, and we don't want to FLUSH_LIMIT because
701 * we could have generated too many delayed refs to
702 * actually allocate, so just bail if we're short and
703 * let the normal reservation dance happen higher up.
704 */
705 if (refill_delayed_refs_rsv) {
706 ret = btrfs_delayed_refs_rsv_refill(fs_info,
707 BTRFS_RESERVE_NO_FLUSH);
708 if (ret) {
709 ret = -EAGAIN;
710 break;
711 }
712 }
713 goto search_again;
714 } else {
715 path->slots[0]--;
716 }
717 }
718 out:
719 if (ret >= 0 && pending_del_nr) {
720 int ret2;
721
722 ret2 = btrfs_del_items(trans, root, path, pending_del_slot, pending_del_nr);
723 if (ret2) {
724 btrfs_abort_transaction(trans, ret2);
725 ret = ret2;
726 }
727 }
728
729 ASSERT(control->last_size >= new_size);
730 if (!ret && control->last_size > new_size)
731 control->last_size = new_size;
732
733 btrfs_free_path(path);
734 return ret;
735 }
736