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 */
81 struct btrfs_inode_extref *
btrfs_lookup_inode_extref(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,const struct fscrypt_str * name,u64 inode_objectid,u64 ref_objectid,int ins_len,int cow)82 btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
83 struct btrfs_root *root,
84 struct btrfs_path *path,
85 const struct fscrypt_str *name,
86 u64 inode_objectid, u64 ref_objectid, int ins_len,
87 int cow)
88 {
89 int ret;
90 struct btrfs_key key;
91
92 key.objectid = inode_objectid;
93 key.type = BTRFS_INODE_EXTREF_KEY;
94 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
95
96 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
97 if (ret < 0)
98 return ERR_PTR(ret);
99 if (ret > 0)
100 return NULL;
101 return btrfs_find_name_in_ext_backref(path->nodes[0], path->slots[0],
102 ref_objectid, name);
103
104 }
105
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)106 static int btrfs_del_inode_extref(struct btrfs_trans_handle *trans,
107 struct btrfs_root *root,
108 const struct fscrypt_str *name,
109 u64 inode_objectid, u64 ref_objectid,
110 u64 *index)
111 {
112 struct btrfs_path *path;
113 struct btrfs_key key;
114 struct btrfs_inode_extref *extref;
115 struct extent_buffer *leaf;
116 int ret;
117 int del_len = name->len + sizeof(*extref);
118 unsigned long ptr;
119 unsigned long item_start;
120 u32 item_size;
121
122 key.objectid = inode_objectid;
123 key.type = BTRFS_INODE_EXTREF_KEY;
124 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
125
126 path = btrfs_alloc_path();
127 if (!path)
128 return -ENOMEM;
129
130 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
131 if (ret > 0)
132 ret = -ENOENT;
133 if (ret < 0)
134 goto out;
135
136 /*
137 * Sanity check - did we find the right item for this name?
138 * This should always succeed so error here will make the FS
139 * readonly.
140 */
141 extref = btrfs_find_name_in_ext_backref(path->nodes[0], path->slots[0],
142 ref_objectid, name);
143 if (!extref) {
144 btrfs_abort_transaction(trans, -ENOENT);
145 ret = -ENOENT;
146 goto out;
147 }
148
149 leaf = path->nodes[0];
150 item_size = btrfs_item_size(leaf, path->slots[0]);
151 if (index)
152 *index = btrfs_inode_extref_index(leaf, extref);
153
154 if (del_len == item_size) {
155 /*
156 * Common case only one ref in the item, remove the
157 * whole item.
158 */
159 ret = btrfs_del_item(trans, root, path);
160 goto out;
161 }
162
163 ptr = (unsigned long)extref;
164 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
165
166 memmove_extent_buffer(leaf, ptr, ptr + del_len,
167 item_size - (ptr + del_len - item_start));
168
169 btrfs_truncate_item(trans, path, item_size - del_len, 1);
170
171 out:
172 btrfs_free_path(path);
173
174 return ret;
175 }
176
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)177 int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
178 struct btrfs_root *root, const struct fscrypt_str *name,
179 u64 inode_objectid, u64 ref_objectid, u64 *index)
180 {
181 struct btrfs_path *path;
182 struct btrfs_key key;
183 struct btrfs_inode_ref *ref;
184 struct extent_buffer *leaf;
185 unsigned long ptr;
186 unsigned long item_start;
187 u32 item_size;
188 u32 sub_item_len;
189 int ret;
190 int search_ext_refs = 0;
191 int del_len = name->len + sizeof(*ref);
192
193 key.objectid = inode_objectid;
194 key.offset = ref_objectid;
195 key.type = BTRFS_INODE_REF_KEY;
196
197 path = btrfs_alloc_path();
198 if (!path)
199 return -ENOMEM;
200
201 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
202 if (ret > 0) {
203 ret = -ENOENT;
204 search_ext_refs = 1;
205 goto out;
206 } else if (ret < 0) {
207 goto out;
208 }
209
210 ref = btrfs_find_name_in_backref(path->nodes[0], path->slots[0], name);
211 if (!ref) {
212 ret = -ENOENT;
213 search_ext_refs = 1;
214 goto out;
215 }
216 leaf = path->nodes[0];
217 item_size = btrfs_item_size(leaf, path->slots[0]);
218
219 if (index)
220 *index = btrfs_inode_ref_index(leaf, ref);
221
222 if (del_len == item_size) {
223 ret = btrfs_del_item(trans, root, path);
224 goto out;
225 }
226 ptr = (unsigned long)ref;
227 sub_item_len = name->len + sizeof(*ref);
228 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
229 memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
230 item_size - (ptr + sub_item_len - item_start));
231 btrfs_truncate_item(trans, path, item_size - sub_item_len, 1);
232 out:
233 btrfs_free_path(path);
234
235 if (search_ext_refs) {
236 /*
237 * No refs were found, or we could not find the
238 * name in our ref array. Find and remove the extended
239 * inode ref then.
240 */
241 return btrfs_del_inode_extref(trans, root, name,
242 inode_objectid, ref_objectid, index);
243 }
244
245 return ret;
246 }
247
248 /*
249 * Insert an extended inode ref into a tree.
250 *
251 * The caller must have checked against BTRFS_LINK_MAX already.
252 */
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)253 static int btrfs_insert_inode_extref(struct btrfs_trans_handle *trans,
254 struct btrfs_root *root,
255 const struct fscrypt_str *name,
256 u64 inode_objectid, u64 ref_objectid,
257 u64 index)
258 {
259 struct btrfs_inode_extref *extref;
260 int ret;
261 int ins_len = name->len + sizeof(*extref);
262 unsigned long ptr;
263 struct btrfs_path *path;
264 struct btrfs_key key;
265 struct extent_buffer *leaf;
266
267 key.objectid = inode_objectid;
268 key.type = BTRFS_INODE_EXTREF_KEY;
269 key.offset = btrfs_extref_hash(ref_objectid, name->name, name->len);
270
271 path = btrfs_alloc_path();
272 if (!path)
273 return -ENOMEM;
274
275 ret = btrfs_insert_empty_item(trans, root, path, &key,
276 ins_len);
277 if (ret == -EEXIST) {
278 if (btrfs_find_name_in_ext_backref(path->nodes[0],
279 path->slots[0],
280 ref_objectid,
281 name))
282 goto out;
283
284 btrfs_extend_item(trans, path, ins_len);
285 ret = 0;
286 }
287 if (ret < 0)
288 goto out;
289
290 leaf = path->nodes[0];
291 ptr = (unsigned long)btrfs_item_ptr(leaf, path->slots[0], char);
292 ptr += btrfs_item_size(leaf, path->slots[0]) - ins_len;
293 extref = (struct btrfs_inode_extref *)ptr;
294
295 btrfs_set_inode_extref_name_len(path->nodes[0], extref, name->len);
296 btrfs_set_inode_extref_index(path->nodes[0], extref, index);
297 btrfs_set_inode_extref_parent(path->nodes[0], extref, ref_objectid);
298
299 ptr = (unsigned long)&extref->name;
300 write_extent_buffer(path->nodes[0], name->name, ptr, name->len);
301 out:
302 btrfs_free_path(path);
303 return ret;
304 }
305
306 /* 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)307 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
308 struct btrfs_root *root, const struct fscrypt_str *name,
309 u64 inode_objectid, u64 ref_objectid, u64 index)
310 {
311 struct btrfs_fs_info *fs_info = root->fs_info;
312 struct btrfs_path *path;
313 struct btrfs_key key;
314 struct btrfs_inode_ref *ref;
315 unsigned long ptr;
316 int ret;
317 int ins_len = name->len + sizeof(*ref);
318
319 key.objectid = inode_objectid;
320 key.offset = ref_objectid;
321 key.type = BTRFS_INODE_REF_KEY;
322
323 path = btrfs_alloc_path();
324 if (!path)
325 return -ENOMEM;
326
327 path->skip_release_on_error = 1;
328 ret = btrfs_insert_empty_item(trans, root, path, &key,
329 ins_len);
330 if (ret == -EEXIST) {
331 u32 old_size;
332 ref = btrfs_find_name_in_backref(path->nodes[0], path->slots[0],
333 name);
334 if (ref)
335 goto out;
336
337 old_size = btrfs_item_size(path->nodes[0], path->slots[0]);
338 btrfs_extend_item(trans, path, ins_len);
339 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
340 struct btrfs_inode_ref);
341 ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
342 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name->len);
343 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
344 ptr = (unsigned long)(ref + 1);
345 ret = 0;
346 } else if (ret < 0) {
347 if (ret == -EOVERFLOW) {
348 if (btrfs_find_name_in_backref(path->nodes[0],
349 path->slots[0],
350 name))
351 ret = -EEXIST;
352 else
353 ret = -EMLINK;
354 }
355 goto out;
356 } else {
357 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
358 struct btrfs_inode_ref);
359 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name->len);
360 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
361 ptr = (unsigned long)(ref + 1);
362 }
363 write_extent_buffer(path->nodes[0], name->name, ptr, name->len);
364 out:
365 btrfs_free_path(path);
366
367 if (ret == -EMLINK) {
368 struct btrfs_super_block *disk_super = fs_info->super_copy;
369 /* We ran out of space in the ref array. Need to
370 * add an extended ref. */
371 if (btrfs_super_incompat_flags(disk_super)
372 & BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
373 ret = btrfs_insert_inode_extref(trans, root, name,
374 inode_objectid,
375 ref_objectid, index);
376 }
377
378 return ret;
379 }
380
btrfs_insert_empty_inode(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,u64 objectid)381 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
382 struct btrfs_root *root,
383 struct btrfs_path *path, u64 objectid)
384 {
385 struct btrfs_key key;
386 int ret;
387 key.objectid = objectid;
388 key.type = BTRFS_INODE_ITEM_KEY;
389 key.offset = 0;
390
391 ret = btrfs_insert_empty_item(trans, root, path, &key,
392 sizeof(struct btrfs_inode_item));
393 return ret;
394 }
395
btrfs_lookup_inode(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_path * path,struct btrfs_key * location,int mod)396 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
397 *root, struct btrfs_path *path,
398 struct btrfs_key *location, int mod)
399 {
400 int ins_len = mod < 0 ? -1 : 0;
401 int cow = mod != 0;
402 int ret;
403 int slot;
404 struct extent_buffer *leaf;
405 struct btrfs_key found_key;
406
407 ret = btrfs_search_slot(trans, root, location, path, ins_len, cow);
408 if (ret > 0 && location->type == BTRFS_ROOT_ITEM_KEY &&
409 location->offset == (u64)-1 && path->slots[0] != 0) {
410 slot = path->slots[0] - 1;
411 leaf = path->nodes[0];
412 btrfs_item_key_to_cpu(leaf, &found_key, slot);
413 if (found_key.objectid == location->objectid &&
414 found_key.type == location->type) {
415 path->slots[0]--;
416 return 0;
417 }
418 }
419 return ret;
420 }
421
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)422 static inline void btrfs_trace_truncate(const struct btrfs_inode *inode,
423 const struct extent_buffer *leaf,
424 const struct btrfs_file_extent_item *fi,
425 u64 offset, int extent_type, int slot)
426 {
427 if (!inode)
428 return;
429 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
430 trace_btrfs_truncate_show_fi_inline(inode, leaf, fi, slot,
431 offset);
432 else
433 trace_btrfs_truncate_show_fi_regular(inode, leaf, fi, offset);
434 }
435
436 /*
437 * Remove inode items from a given root.
438 *
439 * @trans: A transaction handle.
440 * @root: The root from which to remove items.
441 * @inode: The inode whose items we want to remove.
442 * @control: The btrfs_truncate_control to control how and what we
443 * are truncating.
444 *
445 * Remove all keys associated with the inode from the given root that have a key
446 * with a type greater than or equals to @min_type. When @min_type has a value of
447 * BTRFS_EXTENT_DATA_KEY, only remove file extent items that have an offset value
448 * greater than or equals to @new_size. If a file extent item that starts before
449 * @new_size and ends after it is found, its length is adjusted.
450 *
451 * Returns: 0 on success, < 0 on error and NEED_TRUNCATE_BLOCK when @min_type is
452 * BTRFS_EXTENT_DATA_KEY and the caller must truncate the last block.
453 */
btrfs_truncate_inode_items(struct btrfs_trans_handle * trans,struct btrfs_root * root,struct btrfs_truncate_control * control)454 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
455 struct btrfs_root *root,
456 struct btrfs_truncate_control *control)
457 {
458 struct btrfs_fs_info *fs_info = root->fs_info;
459 struct btrfs_path *path;
460 struct extent_buffer *leaf;
461 struct btrfs_file_extent_item *fi;
462 struct btrfs_key key;
463 struct btrfs_key found_key;
464 u64 new_size = control->new_size;
465 u64 extent_num_bytes = 0;
466 u64 extent_offset = 0;
467 u64 item_end = 0;
468 u32 found_type = (u8)-1;
469 int del_item;
470 int pending_del_nr = 0;
471 int pending_del_slot = 0;
472 int extent_type = -1;
473 int ret;
474 u64 bytes_deleted = 0;
475 bool be_nice = false;
476
477 ASSERT(control->inode || !control->clear_extent_range);
478 ASSERT(new_size == 0 || control->min_type == BTRFS_EXTENT_DATA_KEY);
479
480 control->last_size = new_size;
481 control->sub_bytes = 0;
482
483 /*
484 * For shareable roots we want to back off from time to time, this turns
485 * out to be subvolume roots, reloc roots, and data reloc roots.
486 */
487 if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
488 be_nice = true;
489
490 path = btrfs_alloc_path();
491 if (!path)
492 return -ENOMEM;
493 path->reada = READA_BACK;
494
495 key.objectid = control->ino;
496 key.offset = (u64)-1;
497 key.type = (u8)-1;
498
499 search_again:
500 /*
501 * With a 16K leaf size and 128MiB extents, you can actually queue up a
502 * huge file in a single leaf. Most of the time that bytes_deleted is
503 * > 0, it will be huge by the time we get here
504 */
505 if (be_nice && bytes_deleted > SZ_32M &&
506 btrfs_should_end_transaction(trans)) {
507 ret = -EAGAIN;
508 goto out;
509 }
510
511 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
512 if (ret < 0)
513 goto out;
514
515 if (ret > 0) {
516 ret = 0;
517 /* There are no items in the tree for us to truncate, we're done */
518 if (path->slots[0] == 0)
519 goto out;
520 path->slots[0]--;
521 }
522
523 while (1) {
524 u64 clear_start = 0, clear_len = 0, extent_start = 0;
525 bool refill_delayed_refs_rsv = false;
526
527 fi = NULL;
528 leaf = path->nodes[0];
529 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
530 found_type = found_key.type;
531
532 if (found_key.objectid != control->ino)
533 break;
534
535 if (found_type < control->min_type)
536 break;
537
538 item_end = found_key.offset;
539 if (found_type == BTRFS_EXTENT_DATA_KEY) {
540 fi = btrfs_item_ptr(leaf, path->slots[0],
541 struct btrfs_file_extent_item);
542 extent_type = btrfs_file_extent_type(leaf, fi);
543 if (extent_type != BTRFS_FILE_EXTENT_INLINE)
544 item_end +=
545 btrfs_file_extent_num_bytes(leaf, fi);
546 else if (extent_type == BTRFS_FILE_EXTENT_INLINE)
547 item_end += btrfs_file_extent_ram_bytes(leaf, fi);
548
549 btrfs_trace_truncate(control->inode, leaf, fi,
550 found_key.offset, extent_type,
551 path->slots[0]);
552 item_end--;
553 }
554 if (found_type > control->min_type) {
555 del_item = 1;
556 } else {
557 if (item_end < new_size)
558 break;
559 if (found_key.offset >= new_size)
560 del_item = 1;
561 else
562 del_item = 0;
563 }
564
565 /* FIXME, shrink the extent if the ref count is only 1 */
566 if (found_type != BTRFS_EXTENT_DATA_KEY)
567 goto delete;
568
569 control->extents_found++;
570
571 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
572 u64 num_dec;
573
574 clear_start = found_key.offset;
575 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
576 if (!del_item) {
577 u64 orig_num_bytes =
578 btrfs_file_extent_num_bytes(leaf, fi);
579 extent_num_bytes = ALIGN(new_size -
580 found_key.offset,
581 fs_info->sectorsize);
582 clear_start = ALIGN(new_size, fs_info->sectorsize);
583
584 btrfs_set_file_extent_num_bytes(leaf, fi,
585 extent_num_bytes);
586 num_dec = (orig_num_bytes - extent_num_bytes);
587 if (extent_start != 0)
588 control->sub_bytes += num_dec;
589 } else {
590 extent_num_bytes =
591 btrfs_file_extent_disk_num_bytes(leaf, fi);
592 extent_offset = found_key.offset -
593 btrfs_file_extent_offset(leaf, fi);
594
595 /* FIXME blocksize != 4096 */
596 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
597 if (extent_start != 0)
598 control->sub_bytes += num_dec;
599 }
600 clear_len = num_dec;
601 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
602 /*
603 * We can't truncate inline items that have had
604 * special encodings
605 */
606 if (!del_item &&
607 btrfs_file_extent_encryption(leaf, fi) == 0 &&
608 btrfs_file_extent_other_encoding(leaf, fi) == 0 &&
609 btrfs_file_extent_compression(leaf, fi) == 0) {
610 u32 size = (u32)(new_size - found_key.offset);
611
612 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
613 size = btrfs_file_extent_calc_inline_size(size);
614 btrfs_truncate_item(trans, path, size, 1);
615 } else if (!del_item) {
616 /*
617 * We have to bail so the last_size is set to
618 * just before this extent.
619 */
620 ret = BTRFS_NEED_TRUNCATE_BLOCK;
621 break;
622 } else {
623 /*
624 * Inline extents are special, we just treat
625 * them as a full sector worth in the file
626 * extent tree just for simplicity sake.
627 */
628 clear_len = fs_info->sectorsize;
629 }
630
631 control->sub_bytes += item_end + 1 - new_size;
632 }
633 delete:
634 /*
635 * We only want to clear the file extent range if we're
636 * modifying the actual inode's mapping, which is just the
637 * normal truncate path.
638 */
639 if (control->clear_extent_range) {
640 ret = btrfs_inode_clear_file_extent_range(control->inode,
641 clear_start, clear_len);
642 if (ret) {
643 btrfs_abort_transaction(trans, ret);
644 break;
645 }
646 }
647
648 if (del_item) {
649 ASSERT(!pending_del_nr ||
650 ((path->slots[0] + 1) == pending_del_slot));
651
652 control->last_size = found_key.offset;
653 if (!pending_del_nr) {
654 /* No pending yet, add ourselves */
655 pending_del_slot = path->slots[0];
656 pending_del_nr = 1;
657 } else if (path->slots[0] + 1 == pending_del_slot) {
658 /* Hop on the pending chunk */
659 pending_del_nr++;
660 pending_del_slot = path->slots[0];
661 }
662 } else {
663 control->last_size = new_size;
664 break;
665 }
666
667 if (del_item && extent_start != 0 && !control->skip_ref_updates) {
668 struct btrfs_ref ref = {
669 .action = BTRFS_DROP_DELAYED_REF,
670 .bytenr = extent_start,
671 .num_bytes = extent_num_bytes,
672 .owning_root = btrfs_root_id(root),
673 .ref_root = btrfs_header_owner(leaf),
674 };
675
676 bytes_deleted += extent_num_bytes;
677
678 btrfs_init_data_ref(&ref, control->ino, extent_offset,
679 btrfs_root_id(root), false);
680 ret = btrfs_free_extent(trans, &ref);
681 if (ret) {
682 btrfs_abort_transaction(trans, ret);
683 break;
684 }
685 if (be_nice && btrfs_check_space_for_delayed_refs(fs_info))
686 refill_delayed_refs_rsv = true;
687 }
688
689 if (found_type == BTRFS_INODE_ITEM_KEY)
690 break;
691
692 if (path->slots[0] == 0 ||
693 path->slots[0] != pending_del_slot ||
694 refill_delayed_refs_rsv) {
695 if (pending_del_nr) {
696 ret = btrfs_del_items(trans, root, path,
697 pending_del_slot,
698 pending_del_nr);
699 if (ret) {
700 btrfs_abort_transaction(trans, ret);
701 break;
702 }
703 pending_del_nr = 0;
704 }
705 btrfs_release_path(path);
706
707 /*
708 * We can generate a lot of delayed refs, so we need to
709 * throttle every once and a while and make sure we're
710 * adding enough space to keep up with the work we are
711 * generating. Since we hold a transaction here we
712 * can't flush, and we don't want to FLUSH_LIMIT because
713 * we could have generated too many delayed refs to
714 * actually allocate, so just bail if we're short and
715 * let the normal reservation dance happen higher up.
716 */
717 if (refill_delayed_refs_rsv) {
718 ret = btrfs_delayed_refs_rsv_refill(fs_info,
719 BTRFS_RESERVE_NO_FLUSH);
720 if (ret) {
721 ret = -EAGAIN;
722 break;
723 }
724 }
725 goto search_again;
726 } else {
727 path->slots[0]--;
728 }
729 }
730 out:
731 if (ret >= 0 && pending_del_nr) {
732 int err;
733
734 err = btrfs_del_items(trans, root, path, pending_del_slot,
735 pending_del_nr);
736 if (err) {
737 btrfs_abort_transaction(trans, err);
738 ret = err;
739 }
740 }
741
742 ASSERT(control->last_size >= new_size);
743 if (!ret && control->last_size > new_size)
744 control->last_size = new_size;
745
746 btrfs_free_path(path);
747 return ret;
748 }
749