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c1d7c514 | 1 | // SPDX-License-Identifier: GPL-2.0 |
fd708b81 JB |
2 | /* |
3 | * Copyright (C) 2014 Facebook. All rights reserved. | |
fd708b81 JB |
4 | */ |
5 | ||
6 | #include <linux/sched.h> | |
7 | #include <linux/stacktrace.h> | |
9b569ea0 | 8 | #include "messages.h" |
fd708b81 JB |
9 | #include "ctree.h" |
10 | #include "disk-io.h" | |
11 | #include "locking.h" | |
12 | #include "delayed-ref.h" | |
13 | #include "ref-verify.h" | |
fc97a410 | 14 | #include "fs.h" |
07e81dc9 | 15 | #include "accessors.h" |
fd708b81 JB |
16 | |
17 | /* | |
18 | * Used to keep track the roots and number of refs each root has for a given | |
19 | * bytenr. This just tracks the number of direct references, no shared | |
20 | * references. | |
21 | */ | |
22 | struct root_entry { | |
23 | u64 root_objectid; | |
24 | u64 num_refs; | |
25 | struct rb_node node; | |
26 | }; | |
27 | ||
28 | /* | |
29 | * These are meant to represent what should exist in the extent tree, these can | |
30 | * be used to verify the extent tree is consistent as these should all match | |
31 | * what the extent tree says. | |
32 | */ | |
33 | struct ref_entry { | |
34 | u64 root_objectid; | |
35 | u64 parent; | |
36 | u64 owner; | |
37 | u64 offset; | |
38 | u64 num_refs; | |
39 | struct rb_node node; | |
40 | }; | |
41 | ||
42 | #define MAX_TRACE 16 | |
43 | ||
44 | /* | |
45 | * Whenever we add/remove a reference we record the action. The action maps | |
46 | * back to the delayed ref action. We hold the ref we are changing in the | |
47 | * action so we can account for the history properly, and we record the root we | |
48 | * were called with since it could be different from ref_root. We also store | |
52042d8e | 49 | * stack traces because that's how I roll. |
fd708b81 JB |
50 | */ |
51 | struct ref_action { | |
52 | int action; | |
53 | u64 root; | |
54 | struct ref_entry ref; | |
55 | struct list_head list; | |
56 | unsigned long trace[MAX_TRACE]; | |
57 | unsigned int trace_len; | |
58 | }; | |
59 | ||
60 | /* | |
61 | * One of these for every block we reference, it holds the roots and references | |
52042d8e | 62 | * to it as well as all of the ref actions that have occurred to it. We never |
fd708b81 JB |
63 | * free it until we unmount the file system in order to make sure re-allocations |
64 | * are happening properly. | |
65 | */ | |
66 | struct block_entry { | |
67 | u64 bytenr; | |
68 | u64 len; | |
69 | u64 num_refs; | |
70 | int metadata; | |
71 | int from_disk; | |
72 | struct rb_root roots; | |
73 | struct rb_root refs; | |
74 | struct rb_node node; | |
75 | struct list_head actions; | |
76 | }; | |
77 | ||
78 | static struct block_entry *insert_block_entry(struct rb_root *root, | |
79 | struct block_entry *be) | |
80 | { | |
81 | struct rb_node **p = &root->rb_node; | |
82 | struct rb_node *parent_node = NULL; | |
83 | struct block_entry *entry; | |
84 | ||
85 | while (*p) { | |
86 | parent_node = *p; | |
87 | entry = rb_entry(parent_node, struct block_entry, node); | |
88 | if (entry->bytenr > be->bytenr) | |
89 | p = &(*p)->rb_left; | |
90 | else if (entry->bytenr < be->bytenr) | |
91 | p = &(*p)->rb_right; | |
92 | else | |
93 | return entry; | |
94 | } | |
95 | ||
96 | rb_link_node(&be->node, parent_node, p); | |
97 | rb_insert_color(&be->node, root); | |
98 | return NULL; | |
99 | } | |
100 | ||
101 | static struct block_entry *lookup_block_entry(struct rb_root *root, u64 bytenr) | |
102 | { | |
103 | struct rb_node *n; | |
104 | struct block_entry *entry = NULL; | |
105 | ||
106 | n = root->rb_node; | |
107 | while (n) { | |
108 | entry = rb_entry(n, struct block_entry, node); | |
109 | if (entry->bytenr < bytenr) | |
110 | n = n->rb_right; | |
111 | else if (entry->bytenr > bytenr) | |
112 | n = n->rb_left; | |
113 | else | |
114 | return entry; | |
115 | } | |
116 | return NULL; | |
117 | } | |
118 | ||
119 | static struct root_entry *insert_root_entry(struct rb_root *root, | |
120 | struct root_entry *re) | |
121 | { | |
122 | struct rb_node **p = &root->rb_node; | |
123 | struct rb_node *parent_node = NULL; | |
124 | struct root_entry *entry; | |
125 | ||
126 | while (*p) { | |
127 | parent_node = *p; | |
128 | entry = rb_entry(parent_node, struct root_entry, node); | |
129 | if (entry->root_objectid > re->root_objectid) | |
130 | p = &(*p)->rb_left; | |
131 | else if (entry->root_objectid < re->root_objectid) | |
132 | p = &(*p)->rb_right; | |
133 | else | |
134 | return entry; | |
135 | } | |
136 | ||
137 | rb_link_node(&re->node, parent_node, p); | |
138 | rb_insert_color(&re->node, root); | |
139 | return NULL; | |
140 | ||
141 | } | |
142 | ||
143 | static int comp_refs(struct ref_entry *ref1, struct ref_entry *ref2) | |
144 | { | |
145 | if (ref1->root_objectid < ref2->root_objectid) | |
146 | return -1; | |
147 | if (ref1->root_objectid > ref2->root_objectid) | |
148 | return 1; | |
149 | if (ref1->parent < ref2->parent) | |
150 | return -1; | |
151 | if (ref1->parent > ref2->parent) | |
152 | return 1; | |
153 | if (ref1->owner < ref2->owner) | |
154 | return -1; | |
155 | if (ref1->owner > ref2->owner) | |
156 | return 1; | |
157 | if (ref1->offset < ref2->offset) | |
158 | return -1; | |
159 | if (ref1->offset > ref2->offset) | |
160 | return 1; | |
161 | return 0; | |
162 | } | |
163 | ||
164 | static struct ref_entry *insert_ref_entry(struct rb_root *root, | |
165 | struct ref_entry *ref) | |
166 | { | |
167 | struct rb_node **p = &root->rb_node; | |
168 | struct rb_node *parent_node = NULL; | |
169 | struct ref_entry *entry; | |
170 | int cmp; | |
171 | ||
172 | while (*p) { | |
173 | parent_node = *p; | |
174 | entry = rb_entry(parent_node, struct ref_entry, node); | |
175 | cmp = comp_refs(entry, ref); | |
176 | if (cmp > 0) | |
177 | p = &(*p)->rb_left; | |
178 | else if (cmp < 0) | |
179 | p = &(*p)->rb_right; | |
180 | else | |
181 | return entry; | |
182 | } | |
183 | ||
184 | rb_link_node(&ref->node, parent_node, p); | |
185 | rb_insert_color(&ref->node, root); | |
186 | return NULL; | |
187 | ||
188 | } | |
189 | ||
190 | static struct root_entry *lookup_root_entry(struct rb_root *root, u64 objectid) | |
191 | { | |
192 | struct rb_node *n; | |
193 | struct root_entry *entry = NULL; | |
194 | ||
195 | n = root->rb_node; | |
196 | while (n) { | |
197 | entry = rb_entry(n, struct root_entry, node); | |
198 | if (entry->root_objectid < objectid) | |
199 | n = n->rb_right; | |
200 | else if (entry->root_objectid > objectid) | |
201 | n = n->rb_left; | |
202 | else | |
203 | return entry; | |
204 | } | |
205 | return NULL; | |
206 | } | |
207 | ||
208 | #ifdef CONFIG_STACKTRACE | |
209 | static void __save_stack_trace(struct ref_action *ra) | |
210 | { | |
6924f5fe | 211 | ra->trace_len = stack_trace_save(ra->trace, MAX_TRACE, 2); |
fd708b81 JB |
212 | } |
213 | ||
214 | static void __print_stack_trace(struct btrfs_fs_info *fs_info, | |
215 | struct ref_action *ra) | |
216 | { | |
fd708b81 JB |
217 | if (ra->trace_len == 0) { |
218 | btrfs_err(fs_info, " ref-verify: no stacktrace"); | |
219 | return; | |
220 | } | |
6924f5fe | 221 | stack_trace_print(ra->trace, ra->trace_len, 2); |
fd708b81 JB |
222 | } |
223 | #else | |
aedb9d90 | 224 | static inline void __save_stack_trace(struct ref_action *ra) |
fd708b81 JB |
225 | { |
226 | } | |
227 | ||
aedb9d90 | 228 | static inline void __print_stack_trace(struct btrfs_fs_info *fs_info, |
fd708b81 JB |
229 | struct ref_action *ra) |
230 | { | |
231 | btrfs_err(fs_info, " ref-verify: no stacktrace support"); | |
232 | } | |
233 | #endif | |
234 | ||
235 | static void free_block_entry(struct block_entry *be) | |
236 | { | |
237 | struct root_entry *re; | |
238 | struct ref_entry *ref; | |
239 | struct ref_action *ra; | |
240 | struct rb_node *n; | |
241 | ||
242 | while ((n = rb_first(&be->roots))) { | |
243 | re = rb_entry(n, struct root_entry, node); | |
244 | rb_erase(&re->node, &be->roots); | |
245 | kfree(re); | |
246 | } | |
247 | ||
248 | while((n = rb_first(&be->refs))) { | |
249 | ref = rb_entry(n, struct ref_entry, node); | |
250 | rb_erase(&ref->node, &be->refs); | |
251 | kfree(ref); | |
252 | } | |
253 | ||
254 | while (!list_empty(&be->actions)) { | |
255 | ra = list_first_entry(&be->actions, struct ref_action, | |
256 | list); | |
257 | list_del(&ra->list); | |
258 | kfree(ra); | |
259 | } | |
260 | kfree(be); | |
261 | } | |
262 | ||
263 | static struct block_entry *add_block_entry(struct btrfs_fs_info *fs_info, | |
264 | u64 bytenr, u64 len, | |
265 | u64 root_objectid) | |
266 | { | |
267 | struct block_entry *be = NULL, *exist; | |
268 | struct root_entry *re = NULL; | |
269 | ||
5a656c36 FM |
270 | re = kzalloc(sizeof(struct root_entry), GFP_NOFS); |
271 | be = kzalloc(sizeof(struct block_entry), GFP_NOFS); | |
fd708b81 JB |
272 | if (!be || !re) { |
273 | kfree(re); | |
274 | kfree(be); | |
275 | return ERR_PTR(-ENOMEM); | |
276 | } | |
277 | be->bytenr = bytenr; | |
278 | be->len = len; | |
279 | ||
280 | re->root_objectid = root_objectid; | |
281 | re->num_refs = 0; | |
282 | ||
283 | spin_lock(&fs_info->ref_verify_lock); | |
284 | exist = insert_block_entry(&fs_info->block_tree, be); | |
285 | if (exist) { | |
286 | if (root_objectid) { | |
287 | struct root_entry *exist_re; | |
288 | ||
289 | exist_re = insert_root_entry(&exist->roots, re); | |
290 | if (exist_re) | |
291 | kfree(re); | |
d60ba8de TR |
292 | } else { |
293 | kfree(re); | |
fd708b81 JB |
294 | } |
295 | kfree(be); | |
296 | return exist; | |
297 | } | |
298 | ||
299 | be->num_refs = 0; | |
300 | be->metadata = 0; | |
301 | be->from_disk = 0; | |
302 | be->roots = RB_ROOT; | |
303 | be->refs = RB_ROOT; | |
304 | INIT_LIST_HEAD(&be->actions); | |
305 | if (root_objectid) | |
306 | insert_root_entry(&be->roots, re); | |
307 | else | |
308 | kfree(re); | |
309 | return be; | |
310 | } | |
311 | ||
312 | static int add_tree_block(struct btrfs_fs_info *fs_info, u64 ref_root, | |
313 | u64 parent, u64 bytenr, int level) | |
314 | { | |
315 | struct block_entry *be; | |
316 | struct root_entry *re; | |
317 | struct ref_entry *ref = NULL, *exist; | |
318 | ||
5a656c36 | 319 | ref = kmalloc(sizeof(struct ref_entry), GFP_NOFS); |
fd708b81 JB |
320 | if (!ref) |
321 | return -ENOMEM; | |
322 | ||
323 | if (parent) | |
324 | ref->root_objectid = 0; | |
325 | else | |
326 | ref->root_objectid = ref_root; | |
327 | ref->parent = parent; | |
328 | ref->owner = level; | |
329 | ref->offset = 0; | |
330 | ref->num_refs = 1; | |
331 | ||
332 | be = add_block_entry(fs_info, bytenr, fs_info->nodesize, ref_root); | |
333 | if (IS_ERR(be)) { | |
334 | kfree(ref); | |
335 | return PTR_ERR(be); | |
336 | } | |
337 | be->num_refs++; | |
338 | be->from_disk = 1; | |
339 | be->metadata = 1; | |
340 | ||
341 | if (!parent) { | |
342 | ASSERT(ref_root); | |
343 | re = lookup_root_entry(&be->roots, ref_root); | |
344 | ASSERT(re); | |
345 | re->num_refs++; | |
346 | } | |
347 | exist = insert_ref_entry(&be->refs, ref); | |
348 | if (exist) { | |
349 | exist->num_refs++; | |
350 | kfree(ref); | |
351 | } | |
352 | spin_unlock(&fs_info->ref_verify_lock); | |
353 | ||
354 | return 0; | |
355 | } | |
356 | ||
357 | static int add_shared_data_ref(struct btrfs_fs_info *fs_info, | |
358 | u64 parent, u32 num_refs, u64 bytenr, | |
359 | u64 num_bytes) | |
360 | { | |
361 | struct block_entry *be; | |
362 | struct ref_entry *ref; | |
363 | ||
5a656c36 | 364 | ref = kzalloc(sizeof(struct ref_entry), GFP_NOFS); |
fd708b81 JB |
365 | if (!ref) |
366 | return -ENOMEM; | |
367 | be = add_block_entry(fs_info, bytenr, num_bytes, 0); | |
368 | if (IS_ERR(be)) { | |
369 | kfree(ref); | |
370 | return PTR_ERR(be); | |
371 | } | |
372 | be->num_refs += num_refs; | |
373 | ||
374 | ref->parent = parent; | |
375 | ref->num_refs = num_refs; | |
376 | if (insert_ref_entry(&be->refs, ref)) { | |
377 | spin_unlock(&fs_info->ref_verify_lock); | |
378 | btrfs_err(fs_info, "existing shared ref when reading from disk?"); | |
379 | kfree(ref); | |
380 | return -EINVAL; | |
381 | } | |
382 | spin_unlock(&fs_info->ref_verify_lock); | |
383 | return 0; | |
384 | } | |
385 | ||
386 | static int add_extent_data_ref(struct btrfs_fs_info *fs_info, | |
387 | struct extent_buffer *leaf, | |
388 | struct btrfs_extent_data_ref *dref, | |
389 | u64 bytenr, u64 num_bytes) | |
390 | { | |
391 | struct block_entry *be; | |
392 | struct ref_entry *ref; | |
393 | struct root_entry *re; | |
394 | u64 ref_root = btrfs_extent_data_ref_root(leaf, dref); | |
395 | u64 owner = btrfs_extent_data_ref_objectid(leaf, dref); | |
396 | u64 offset = btrfs_extent_data_ref_offset(leaf, dref); | |
397 | u32 num_refs = btrfs_extent_data_ref_count(leaf, dref); | |
398 | ||
5a656c36 | 399 | ref = kzalloc(sizeof(struct ref_entry), GFP_NOFS); |
fd708b81 JB |
400 | if (!ref) |
401 | return -ENOMEM; | |
402 | be = add_block_entry(fs_info, bytenr, num_bytes, ref_root); | |
403 | if (IS_ERR(be)) { | |
404 | kfree(ref); | |
405 | return PTR_ERR(be); | |
406 | } | |
407 | be->num_refs += num_refs; | |
408 | ||
409 | ref->parent = 0; | |
410 | ref->owner = owner; | |
411 | ref->root_objectid = ref_root; | |
412 | ref->offset = offset; | |
413 | ref->num_refs = num_refs; | |
414 | if (insert_ref_entry(&be->refs, ref)) { | |
415 | spin_unlock(&fs_info->ref_verify_lock); | |
416 | btrfs_err(fs_info, "existing ref when reading from disk?"); | |
417 | kfree(ref); | |
418 | return -EINVAL; | |
419 | } | |
420 | ||
421 | re = lookup_root_entry(&be->roots, ref_root); | |
422 | if (!re) { | |
423 | spin_unlock(&fs_info->ref_verify_lock); | |
424 | btrfs_err(fs_info, "missing root in new block entry?"); | |
425 | return -EINVAL; | |
426 | } | |
427 | re->num_refs += num_refs; | |
428 | spin_unlock(&fs_info->ref_verify_lock); | |
429 | return 0; | |
430 | } | |
431 | ||
432 | static int process_extent_item(struct btrfs_fs_info *fs_info, | |
433 | struct btrfs_path *path, struct btrfs_key *key, | |
434 | int slot, int *tree_block_level) | |
435 | { | |
436 | struct btrfs_extent_item *ei; | |
437 | struct btrfs_extent_inline_ref *iref; | |
438 | struct btrfs_extent_data_ref *dref; | |
439 | struct btrfs_shared_data_ref *sref; | |
440 | struct extent_buffer *leaf = path->nodes[0]; | |
3212fa14 | 441 | u32 item_size = btrfs_item_size(leaf, slot); |
fd708b81 JB |
442 | unsigned long end, ptr; |
443 | u64 offset, flags, count; | |
444 | int type, ret; | |
445 | ||
446 | ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); | |
447 | flags = btrfs_extent_flags(leaf, ei); | |
448 | ||
449 | if ((key->type == BTRFS_EXTENT_ITEM_KEY) && | |
450 | flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
451 | struct btrfs_tree_block_info *info; | |
452 | ||
453 | info = (struct btrfs_tree_block_info *)(ei + 1); | |
454 | *tree_block_level = btrfs_tree_block_level(leaf, info); | |
455 | iref = (struct btrfs_extent_inline_ref *)(info + 1); | |
456 | } else { | |
457 | if (key->type == BTRFS_METADATA_ITEM_KEY) | |
458 | *tree_block_level = key->offset; | |
459 | iref = (struct btrfs_extent_inline_ref *)(ei + 1); | |
460 | } | |
461 | ||
462 | ptr = (unsigned long)iref; | |
463 | end = (unsigned long)ei + item_size; | |
464 | while (ptr < end) { | |
465 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
466 | type = btrfs_extent_inline_ref_type(leaf, iref); | |
467 | offset = btrfs_extent_inline_ref_offset(leaf, iref); | |
468 | switch (type) { | |
469 | case BTRFS_TREE_BLOCK_REF_KEY: | |
470 | ret = add_tree_block(fs_info, offset, 0, key->objectid, | |
471 | *tree_block_level); | |
472 | break; | |
473 | case BTRFS_SHARED_BLOCK_REF_KEY: | |
474 | ret = add_tree_block(fs_info, 0, offset, key->objectid, | |
475 | *tree_block_level); | |
476 | break; | |
477 | case BTRFS_EXTENT_DATA_REF_KEY: | |
478 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
479 | ret = add_extent_data_ref(fs_info, leaf, dref, | |
480 | key->objectid, key->offset); | |
481 | break; | |
482 | case BTRFS_SHARED_DATA_REF_KEY: | |
483 | sref = (struct btrfs_shared_data_ref *)(iref + 1); | |
484 | count = btrfs_shared_data_ref_count(leaf, sref); | |
485 | ret = add_shared_data_ref(fs_info, offset, count, | |
486 | key->objectid, key->offset); | |
487 | break; | |
488 | default: | |
489 | btrfs_err(fs_info, "invalid key type in iref"); | |
490 | ret = -EINVAL; | |
491 | break; | |
492 | } | |
493 | if (ret) | |
494 | break; | |
495 | ptr += btrfs_extent_inline_ref_size(type); | |
496 | } | |
497 | return ret; | |
498 | } | |
499 | ||
500 | static int process_leaf(struct btrfs_root *root, | |
0d73a11c JB |
501 | struct btrfs_path *path, u64 *bytenr, u64 *num_bytes, |
502 | int *tree_block_level) | |
fd708b81 JB |
503 | { |
504 | struct btrfs_fs_info *fs_info = root->fs_info; | |
505 | struct extent_buffer *leaf = path->nodes[0]; | |
506 | struct btrfs_extent_data_ref *dref; | |
507 | struct btrfs_shared_data_ref *sref; | |
508 | u32 count; | |
0d73a11c | 509 | int i = 0, ret = 0; |
fd708b81 JB |
510 | struct btrfs_key key; |
511 | int nritems = btrfs_header_nritems(leaf); | |
512 | ||
513 | for (i = 0; i < nritems; i++) { | |
514 | btrfs_item_key_to_cpu(leaf, &key, i); | |
515 | switch (key.type) { | |
516 | case BTRFS_EXTENT_ITEM_KEY: | |
517 | *num_bytes = key.offset; | |
c730ae0c | 518 | fallthrough; |
fd708b81 JB |
519 | case BTRFS_METADATA_ITEM_KEY: |
520 | *bytenr = key.objectid; | |
521 | ret = process_extent_item(fs_info, path, &key, i, | |
0d73a11c | 522 | tree_block_level); |
fd708b81 JB |
523 | break; |
524 | case BTRFS_TREE_BLOCK_REF_KEY: | |
525 | ret = add_tree_block(fs_info, key.offset, 0, | |
0d73a11c | 526 | key.objectid, *tree_block_level); |
fd708b81 JB |
527 | break; |
528 | case BTRFS_SHARED_BLOCK_REF_KEY: | |
529 | ret = add_tree_block(fs_info, 0, key.offset, | |
0d73a11c | 530 | key.objectid, *tree_block_level); |
fd708b81 JB |
531 | break; |
532 | case BTRFS_EXTENT_DATA_REF_KEY: | |
533 | dref = btrfs_item_ptr(leaf, i, | |
534 | struct btrfs_extent_data_ref); | |
535 | ret = add_extent_data_ref(fs_info, leaf, dref, *bytenr, | |
536 | *num_bytes); | |
537 | break; | |
538 | case BTRFS_SHARED_DATA_REF_KEY: | |
539 | sref = btrfs_item_ptr(leaf, i, | |
540 | struct btrfs_shared_data_ref); | |
541 | count = btrfs_shared_data_ref_count(leaf, sref); | |
542 | ret = add_shared_data_ref(fs_info, key.offset, count, | |
543 | *bytenr, *num_bytes); | |
544 | break; | |
545 | default: | |
546 | break; | |
547 | } | |
548 | if (ret) | |
549 | break; | |
550 | } | |
551 | return ret; | |
552 | } | |
553 | ||
554 | /* Walk down to the leaf from the given level */ | |
555 | static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path, | |
0d73a11c JB |
556 | int level, u64 *bytenr, u64 *num_bytes, |
557 | int *tree_block_level) | |
fd708b81 | 558 | { |
fd708b81 | 559 | struct extent_buffer *eb; |
fd708b81 JB |
560 | int ret = 0; |
561 | ||
562 | while (level >= 0) { | |
563 | if (level) { | |
c990ada2 JB |
564 | eb = btrfs_read_node_slot(path->nodes[level], |
565 | path->slots[level]); | |
fd708b81 JB |
566 | if (IS_ERR(eb)) |
567 | return PTR_ERR(eb); | |
fd708b81 | 568 | btrfs_tree_read_lock(eb); |
fd708b81 JB |
569 | path->nodes[level-1] = eb; |
570 | path->slots[level-1] = 0; | |
ac5887c8 | 571 | path->locks[level-1] = BTRFS_READ_LOCK; |
fd708b81 | 572 | } else { |
0d73a11c JB |
573 | ret = process_leaf(root, path, bytenr, num_bytes, |
574 | tree_block_level); | |
fd708b81 JB |
575 | if (ret) |
576 | break; | |
577 | } | |
578 | level--; | |
579 | } | |
580 | return ret; | |
581 | } | |
582 | ||
583 | /* Walk up to the next node that needs to be processed */ | |
02cfe779 | 584 | static int walk_up_tree(struct btrfs_path *path, int *level) |
fd708b81 JB |
585 | { |
586 | int l; | |
587 | ||
588 | for (l = 0; l < BTRFS_MAX_LEVEL; l++) { | |
589 | if (!path->nodes[l]) | |
590 | continue; | |
591 | if (l) { | |
592 | path->slots[l]++; | |
593 | if (path->slots[l] < | |
594 | btrfs_header_nritems(path->nodes[l])) { | |
595 | *level = l; | |
596 | return 0; | |
597 | } | |
598 | } | |
599 | btrfs_tree_unlock_rw(path->nodes[l], path->locks[l]); | |
600 | free_extent_buffer(path->nodes[l]); | |
601 | path->nodes[l] = NULL; | |
602 | path->slots[l] = 0; | |
603 | path->locks[l] = 0; | |
604 | } | |
605 | ||
606 | return 1; | |
607 | } | |
608 | ||
609 | static void dump_ref_action(struct btrfs_fs_info *fs_info, | |
610 | struct ref_action *ra) | |
611 | { | |
612 | btrfs_err(fs_info, | |
613 | " Ref action %d, root %llu, ref_root %llu, parent %llu, owner %llu, offset %llu, num_refs %llu", | |
614 | ra->action, ra->root, ra->ref.root_objectid, ra->ref.parent, | |
615 | ra->ref.owner, ra->ref.offset, ra->ref.num_refs); | |
616 | __print_stack_trace(fs_info, ra); | |
617 | } | |
618 | ||
619 | /* | |
620 | * Dumps all the information from the block entry to printk, it's going to be | |
621 | * awesome. | |
622 | */ | |
623 | static void dump_block_entry(struct btrfs_fs_info *fs_info, | |
624 | struct block_entry *be) | |
625 | { | |
626 | struct ref_entry *ref; | |
627 | struct root_entry *re; | |
628 | struct ref_action *ra; | |
629 | struct rb_node *n; | |
630 | ||
631 | btrfs_err(fs_info, | |
632 | "dumping block entry [%llu %llu], num_refs %llu, metadata %d, from disk %d", | |
633 | be->bytenr, be->len, be->num_refs, be->metadata, | |
634 | be->from_disk); | |
635 | ||
636 | for (n = rb_first(&be->refs); n; n = rb_next(n)) { | |
637 | ref = rb_entry(n, struct ref_entry, node); | |
638 | btrfs_err(fs_info, | |
639 | " ref root %llu, parent %llu, owner %llu, offset %llu, num_refs %llu", | |
640 | ref->root_objectid, ref->parent, ref->owner, | |
641 | ref->offset, ref->num_refs); | |
642 | } | |
643 | ||
644 | for (n = rb_first(&be->roots); n; n = rb_next(n)) { | |
645 | re = rb_entry(n, struct root_entry, node); | |
646 | btrfs_err(fs_info, " root entry %llu, num_refs %llu", | |
647 | re->root_objectid, re->num_refs); | |
648 | } | |
649 | ||
650 | list_for_each_entry(ra, &be->actions, list) | |
651 | dump_ref_action(fs_info, ra); | |
652 | } | |
653 | ||
654 | /* | |
655 | * btrfs_ref_tree_mod: called when we modify a ref for a bytenr | |
fd708b81 JB |
656 | * |
657 | * This will add an action item to the given bytenr and do sanity checks to make | |
658 | * sure we haven't messed something up. If we are making a new allocation and | |
659 | * this block entry has history we will delete all previous actions as long as | |
660 | * our sanity checks pass as they are no longer needed. | |
661 | */ | |
8a5040f7 QW |
662 | int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, |
663 | struct btrfs_ref *generic_ref) | |
fd708b81 | 664 | { |
fd708b81 JB |
665 | struct ref_entry *ref = NULL, *exist; |
666 | struct ref_action *ra = NULL; | |
667 | struct block_entry *be = NULL; | |
668 | struct root_entry *re = NULL; | |
8a5040f7 | 669 | int action = generic_ref->action; |
fd708b81 | 670 | int ret = 0; |
8a5040f7 QW |
671 | bool metadata; |
672 | u64 bytenr = generic_ref->bytenr; | |
673 | u64 num_bytes = generic_ref->len; | |
674 | u64 parent = generic_ref->parent; | |
1478143a JB |
675 | u64 ref_root = 0; |
676 | u64 owner = 0; | |
677 | u64 offset = 0; | |
fd708b81 | 678 | |
8a5040f7 | 679 | if (!btrfs_test_opt(fs_info, REF_VERIFY)) |
fd708b81 JB |
680 | return 0; |
681 | ||
8a5040f7 | 682 | if (generic_ref->type == BTRFS_REF_METADATA) { |
1478143a | 683 | if (!parent) |
113479d5 | 684 | ref_root = generic_ref->tree_ref.owning_root; |
8a5040f7 | 685 | owner = generic_ref->tree_ref.level; |
1478143a | 686 | } else if (!parent) { |
113479d5 | 687 | ref_root = generic_ref->data_ref.owning_root; |
8a5040f7 QW |
688 | owner = generic_ref->data_ref.ino; |
689 | offset = generic_ref->data_ref.offset; | |
690 | } | |
691 | metadata = owner < BTRFS_FIRST_FREE_OBJECTID; | |
692 | ||
fd708b81 JB |
693 | ref = kzalloc(sizeof(struct ref_entry), GFP_NOFS); |
694 | ra = kmalloc(sizeof(struct ref_action), GFP_NOFS); | |
695 | if (!ra || !ref) { | |
696 | kfree(ref); | |
697 | kfree(ra); | |
698 | ret = -ENOMEM; | |
699 | goto out; | |
700 | } | |
701 | ||
1478143a JB |
702 | ref->parent = parent; |
703 | ref->owner = owner; | |
704 | ref->root_objectid = ref_root; | |
705 | ref->offset = offset; | |
fd708b81 JB |
706 | ref->num_refs = (action == BTRFS_DROP_DELAYED_REF) ? -1 : 1; |
707 | ||
708 | memcpy(&ra->ref, ref, sizeof(struct ref_entry)); | |
709 | /* | |
710 | * Save the extra info from the delayed ref in the ref action to make it | |
711 | * easier to figure out what is happening. The real ref's we add to the | |
712 | * ref tree need to reflect what we save on disk so it matches any | |
713 | * on-disk refs we pre-loaded. | |
714 | */ | |
715 | ra->ref.owner = owner; | |
716 | ra->ref.offset = offset; | |
717 | ra->ref.root_objectid = ref_root; | |
718 | __save_stack_trace(ra); | |
719 | ||
720 | INIT_LIST_HEAD(&ra->list); | |
721 | ra->action = action; | |
8a5040f7 | 722 | ra->root = generic_ref->real_root; |
fd708b81 JB |
723 | |
724 | /* | |
725 | * This is an allocation, preallocate the block_entry in case we haven't | |
726 | * used it before. | |
727 | */ | |
728 | ret = -EINVAL; | |
729 | if (action == BTRFS_ADD_DELAYED_EXTENT) { | |
730 | /* | |
731 | * For subvol_create we'll just pass in whatever the parent root | |
732 | * is and the new root objectid, so let's not treat the passed | |
733 | * in root as if it really has a ref for this bytenr. | |
734 | */ | |
8a5040f7 | 735 | be = add_block_entry(fs_info, bytenr, num_bytes, ref_root); |
fd708b81 | 736 | if (IS_ERR(be)) { |
f311ade3 | 737 | kfree(ref); |
fd708b81 JB |
738 | kfree(ra); |
739 | ret = PTR_ERR(be); | |
740 | goto out; | |
741 | } | |
742 | be->num_refs++; | |
743 | if (metadata) | |
744 | be->metadata = 1; | |
745 | ||
746 | if (be->num_refs != 1) { | |
747 | btrfs_err(fs_info, | |
748 | "re-allocated a block that still has references to it!"); | |
749 | dump_block_entry(fs_info, be); | |
750 | dump_ref_action(fs_info, ra); | |
f311ade3 WW |
751 | kfree(ref); |
752 | kfree(ra); | |
fd708b81 JB |
753 | goto out_unlock; |
754 | } | |
755 | ||
756 | while (!list_empty(&be->actions)) { | |
757 | struct ref_action *tmp; | |
758 | ||
759 | tmp = list_first_entry(&be->actions, struct ref_action, | |
760 | list); | |
761 | list_del(&tmp->list); | |
762 | kfree(tmp); | |
763 | } | |
764 | } else { | |
765 | struct root_entry *tmp; | |
766 | ||
767 | if (!parent) { | |
768 | re = kmalloc(sizeof(struct root_entry), GFP_NOFS); | |
769 | if (!re) { | |
770 | kfree(ref); | |
771 | kfree(ra); | |
772 | ret = -ENOMEM; | |
773 | goto out; | |
774 | } | |
775 | /* | |
776 | * This is the root that is modifying us, so it's the | |
777 | * one we want to lookup below when we modify the | |
778 | * re->num_refs. | |
779 | */ | |
8a5040f7 QW |
780 | ref_root = generic_ref->real_root; |
781 | re->root_objectid = generic_ref->real_root; | |
fd708b81 JB |
782 | re->num_refs = 0; |
783 | } | |
784 | ||
8a5040f7 QW |
785 | spin_lock(&fs_info->ref_verify_lock); |
786 | be = lookup_block_entry(&fs_info->block_tree, bytenr); | |
fd708b81 JB |
787 | if (!be) { |
788 | btrfs_err(fs_info, | |
789 | "trying to do action %d to bytenr %llu num_bytes %llu but there is no existing entry!", | |
cc7c7714 | 790 | action, bytenr, num_bytes); |
fd708b81 JB |
791 | dump_ref_action(fs_info, ra); |
792 | kfree(ref); | |
793 | kfree(ra); | |
794 | goto out_unlock; | |
b39c8f5a JB |
795 | } else if (be->num_refs == 0) { |
796 | btrfs_err(fs_info, | |
797 | "trying to do action %d for a bytenr that has 0 total references", | |
798 | action); | |
799 | dump_block_entry(fs_info, be); | |
800 | dump_ref_action(fs_info, ra); | |
801 | kfree(ref); | |
802 | kfree(ra); | |
803 | goto out_unlock; | |
fd708b81 JB |
804 | } |
805 | ||
806 | if (!parent) { | |
807 | tmp = insert_root_entry(&be->roots, re); | |
808 | if (tmp) { | |
809 | kfree(re); | |
810 | re = tmp; | |
811 | } | |
812 | } | |
813 | } | |
814 | ||
815 | exist = insert_ref_entry(&be->refs, ref); | |
816 | if (exist) { | |
817 | if (action == BTRFS_DROP_DELAYED_REF) { | |
818 | if (exist->num_refs == 0) { | |
819 | btrfs_err(fs_info, | |
820 | "dropping a ref for a existing root that doesn't have a ref on the block"); | |
821 | dump_block_entry(fs_info, be); | |
822 | dump_ref_action(fs_info, ra); | |
f311ade3 | 823 | kfree(ref); |
fd708b81 JB |
824 | kfree(ra); |
825 | goto out_unlock; | |
826 | } | |
827 | exist->num_refs--; | |
828 | if (exist->num_refs == 0) { | |
829 | rb_erase(&exist->node, &be->refs); | |
830 | kfree(exist); | |
831 | } | |
832 | } else if (!be->metadata) { | |
833 | exist->num_refs++; | |
834 | } else { | |
835 | btrfs_err(fs_info, | |
836 | "attempting to add another ref for an existing ref on a tree block"); | |
837 | dump_block_entry(fs_info, be); | |
838 | dump_ref_action(fs_info, ra); | |
f311ade3 | 839 | kfree(ref); |
fd708b81 JB |
840 | kfree(ra); |
841 | goto out_unlock; | |
842 | } | |
843 | kfree(ref); | |
844 | } else { | |
845 | if (action == BTRFS_DROP_DELAYED_REF) { | |
846 | btrfs_err(fs_info, | |
847 | "dropping a ref for a root that doesn't have a ref on the block"); | |
848 | dump_block_entry(fs_info, be); | |
849 | dump_ref_action(fs_info, ra); | |
468600c6 | 850 | kfree(ref); |
fd708b81 JB |
851 | kfree(ra); |
852 | goto out_unlock; | |
853 | } | |
854 | } | |
855 | ||
856 | if (!parent && !re) { | |
857 | re = lookup_root_entry(&be->roots, ref_root); | |
858 | if (!re) { | |
859 | /* | |
860 | * This shouldn't happen because we will add our re | |
861 | * above when we lookup the be with !parent, but just in | |
862 | * case catch this case so we don't panic because I | |
52042d8e | 863 | * didn't think of some other corner case. |
fd708b81 JB |
864 | */ |
865 | btrfs_err(fs_info, "failed to find root %llu for %llu", | |
8a5040f7 | 866 | generic_ref->real_root, be->bytenr); |
fd708b81 JB |
867 | dump_block_entry(fs_info, be); |
868 | dump_ref_action(fs_info, ra); | |
869 | kfree(ra); | |
870 | goto out_unlock; | |
871 | } | |
872 | } | |
873 | if (action == BTRFS_DROP_DELAYED_REF) { | |
874 | if (re) | |
875 | re->num_refs--; | |
876 | be->num_refs--; | |
877 | } else if (action == BTRFS_ADD_DELAYED_REF) { | |
878 | be->num_refs++; | |
879 | if (re) | |
880 | re->num_refs++; | |
881 | } | |
882 | list_add_tail(&ra->list, &be->actions); | |
883 | ret = 0; | |
884 | out_unlock: | |
8a5040f7 | 885 | spin_unlock(&fs_info->ref_verify_lock); |
fd708b81 JB |
886 | out: |
887 | if (ret) | |
888 | btrfs_clear_opt(fs_info->mount_opt, REF_VERIFY); | |
889 | return ret; | |
890 | } | |
891 | ||
892 | /* Free up the ref cache */ | |
893 | void btrfs_free_ref_cache(struct btrfs_fs_info *fs_info) | |
894 | { | |
895 | struct block_entry *be; | |
896 | struct rb_node *n; | |
897 | ||
898 | if (!btrfs_test_opt(fs_info, REF_VERIFY)) | |
899 | return; | |
900 | ||
901 | spin_lock(&fs_info->ref_verify_lock); | |
902 | while ((n = rb_first(&fs_info->block_tree))) { | |
903 | be = rb_entry(n, struct block_entry, node); | |
904 | rb_erase(&be->node, &fs_info->block_tree); | |
905 | free_block_entry(be); | |
906 | cond_resched_lock(&fs_info->ref_verify_lock); | |
907 | } | |
908 | spin_unlock(&fs_info->ref_verify_lock); | |
909 | } | |
910 | ||
911 | void btrfs_free_ref_tree_range(struct btrfs_fs_info *fs_info, u64 start, | |
912 | u64 len) | |
913 | { | |
914 | struct block_entry *be = NULL, *entry; | |
915 | struct rb_node *n; | |
916 | ||
917 | if (!btrfs_test_opt(fs_info, REF_VERIFY)) | |
918 | return; | |
919 | ||
920 | spin_lock(&fs_info->ref_verify_lock); | |
921 | n = fs_info->block_tree.rb_node; | |
922 | while (n) { | |
923 | entry = rb_entry(n, struct block_entry, node); | |
924 | if (entry->bytenr < start) { | |
925 | n = n->rb_right; | |
926 | } else if (entry->bytenr > start) { | |
927 | n = n->rb_left; | |
928 | } else { | |
929 | be = entry; | |
930 | break; | |
931 | } | |
932 | /* We want to get as close to start as possible */ | |
933 | if (be == NULL || | |
934 | (entry->bytenr < start && be->bytenr > start) || | |
935 | (entry->bytenr < start && entry->bytenr > be->bytenr)) | |
936 | be = entry; | |
937 | } | |
938 | ||
939 | /* | |
940 | * Could have an empty block group, maybe have something to check for | |
941 | * this case to verify we were actually empty? | |
942 | */ | |
943 | if (!be) { | |
944 | spin_unlock(&fs_info->ref_verify_lock); | |
945 | return; | |
946 | } | |
947 | ||
948 | n = &be->node; | |
949 | while (n) { | |
950 | be = rb_entry(n, struct block_entry, node); | |
951 | n = rb_next(n); | |
952 | if (be->bytenr < start && be->bytenr + be->len > start) { | |
953 | btrfs_err(fs_info, | |
954 | "block entry overlaps a block group [%llu,%llu]!", | |
955 | start, len); | |
956 | dump_block_entry(fs_info, be); | |
957 | continue; | |
958 | } | |
959 | if (be->bytenr < start) | |
960 | continue; | |
961 | if (be->bytenr >= start + len) | |
962 | break; | |
963 | if (be->bytenr + be->len > start + len) { | |
964 | btrfs_err(fs_info, | |
965 | "block entry overlaps a block group [%llu,%llu]!", | |
966 | start, len); | |
967 | dump_block_entry(fs_info, be); | |
968 | } | |
969 | rb_erase(&be->node, &fs_info->block_tree); | |
970 | free_block_entry(be); | |
971 | } | |
972 | spin_unlock(&fs_info->ref_verify_lock); | |
973 | } | |
974 | ||
975 | /* Walk down all roots and build the ref tree, meant to be called at mount */ | |
976 | int btrfs_build_ref_tree(struct btrfs_fs_info *fs_info) | |
977 | { | |
29cbcf40 | 978 | struct btrfs_root *extent_root; |
fd708b81 | 979 | struct btrfs_path *path; |
fd708b81 | 980 | struct extent_buffer *eb; |
0d73a11c | 981 | int tree_block_level = 0; |
fd708b81 JB |
982 | u64 bytenr = 0, num_bytes = 0; |
983 | int ret, level; | |
984 | ||
985 | if (!btrfs_test_opt(fs_info, REF_VERIFY)) | |
986 | return 0; | |
987 | ||
988 | path = btrfs_alloc_path(); | |
989 | if (!path) | |
990 | return -ENOMEM; | |
991 | ||
29cbcf40 JB |
992 | extent_root = btrfs_extent_root(fs_info, 0); |
993 | eb = btrfs_read_lock_root_node(extent_root); | |
fd708b81 JB |
994 | level = btrfs_header_level(eb); |
995 | path->nodes[level] = eb; | |
996 | path->slots[level] = 0; | |
ac5887c8 | 997 | path->locks[level] = BTRFS_READ_LOCK; |
fd708b81 JB |
998 | |
999 | while (1) { | |
1000 | /* | |
1001 | * We have to keep track of the bytenr/num_bytes we last hit | |
1002 | * because we could have run out of space for an inline ref, and | |
1003 | * would have had to added a ref key item which may appear on a | |
1004 | * different leaf from the original extent item. | |
1005 | */ | |
29cbcf40 | 1006 | ret = walk_down_tree(extent_root, path, level, |
0d73a11c | 1007 | &bytenr, &num_bytes, &tree_block_level); |
fd708b81 JB |
1008 | if (ret) |
1009 | break; | |
02cfe779 | 1010 | ret = walk_up_tree(path, &level); |
fd708b81 JB |
1011 | if (ret < 0) |
1012 | break; | |
1013 | if (ret > 0) { | |
1014 | ret = 0; | |
1015 | break; | |
1016 | } | |
1017 | } | |
1018 | if (ret) { | |
1019 | btrfs_clear_opt(fs_info->mount_opt, REF_VERIFY); | |
1020 | btrfs_free_ref_cache(fs_info); | |
1021 | } | |
1022 | btrfs_free_path(path); | |
1023 | return ret; | |
1024 | } |