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Btrfs: fix memory leak of orphan block rsv
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CommitLineData
6cbd5570
CM
1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
8ea05e3a 19#include <linux/uuid.h>
3768f368 20#include "ctree.h"
5eda7b5e 21#include "transaction.h"
3768f368
CM
22#include "disk-io.h"
23#include "print-tree.h"
24
8ea05e3a
AB
25/*
26 * Read a root item from the tree. In case we detect a root item smaller then
27 * sizeof(root_item), we know it's an old version of the root structure and
28 * initialize all new fields to zero. The same happens if we detect mismatching
29 * generation numbers as then we know the root was once mounted with an older
30 * kernel that was not aware of the root item structure change.
31 */
171170c1
ST
32static void btrfs_read_root_item(struct extent_buffer *eb, int slot,
33 struct btrfs_root_item *item)
8ea05e3a
AB
34{
35 uuid_le uuid;
36 int len;
37 int need_reset = 0;
38
39 len = btrfs_item_size_nr(eb, slot);
40 read_extent_buffer(eb, item, btrfs_item_ptr_offset(eb, slot),
41 min_t(int, len, (int)sizeof(*item)));
42 if (len < sizeof(*item))
43 need_reset = 1;
44 if (!need_reset && btrfs_root_generation(item)
45 != btrfs_root_generation_v2(item)) {
46 if (btrfs_root_generation_v2(item) != 0) {
47 printk(KERN_WARNING "btrfs: mismatching "
48 "generation and generation_v2 "
49 "found in root item. This root "
50 "was probably mounted with an "
51 "older kernel. Resetting all "
52 "new fields.\n");
53 }
54 need_reset = 1;
55 }
56 if (need_reset) {
57 memset(&item->generation_v2, 0,
58 sizeof(*item) - offsetof(struct btrfs_root_item,
59 generation_v2));
60
61 uuid_le_gen(&uuid);
62 memcpy(item->uuid, uuid.b, BTRFS_UUID_SIZE);
63 }
64}
65
d352ac68 66/*
cb517eab
MX
67 * btrfs_find_root - lookup the root by the key.
68 * root: the root of the root tree
69 * search_key: the key to search
70 * path: the path we search
71 * root_item: the root item of the tree we look for
72 * root_key: the reak key of the tree we look for
73 *
74 * If ->offset of 'seach_key' is -1ULL, it means we are not sure the offset
75 * of the search key, just lookup the root with the highest offset for a
76 * given objectid.
77 *
78 * If we find something return 0, otherwise > 0, < 0 on error.
d352ac68 79 */
cb517eab
MX
80int btrfs_find_root(struct btrfs_root *root, struct btrfs_key *search_key,
81 struct btrfs_path *path, struct btrfs_root_item *root_item,
82 struct btrfs_key *root_key)
3768f368 83{
5f39d397
CM
84 struct btrfs_key found_key;
85 struct extent_buffer *l;
3768f368
CM
86 int ret;
87 int slot;
88
cb517eab 89 ret = btrfs_search_slot(NULL, root, search_key, path, 0, 0);
3768f368 90 if (ret < 0)
cb517eab 91 return ret;
5f39d397 92
cb517eab
MX
93 if (search_key->offset != -1ULL) { /* the search key is exact */
94 if (ret > 0)
95 goto out;
96 } else {
97 BUG_ON(ret == 0); /* Logical error */
98 if (path->slots[0] == 0)
99 goto out;
100 path->slots[0]--;
101 ret = 0;
76dda93c 102 }
cb517eab 103
5f39d397 104 l = path->nodes[0];
cb517eab
MX
105 slot = path->slots[0];
106
5f39d397 107 btrfs_item_key_to_cpu(l, &found_key, slot);
cb517eab 108 if (found_key.objectid != search_key->objectid ||
76dda93c 109 found_key.type != BTRFS_ROOT_ITEM_KEY) {
3768f368
CM
110 ret = 1;
111 goto out;
112 }
8ea05e3a 113
cb517eab
MX
114 if (root_item)
115 btrfs_read_root_item(l, slot, root_item);
116 if (root_key)
117 memcpy(root_key, &found_key, sizeof(found_key));
3768f368 118out:
cb517eab 119 btrfs_release_path(path);
3768f368
CM
120 return ret;
121}
122
bf5f32ec
MF
123void btrfs_set_root_node(struct btrfs_root_item *item,
124 struct extent_buffer *node)
5d4f98a2
YZ
125{
126 btrfs_set_root_bytenr(item, node->start);
127 btrfs_set_root_level(item, btrfs_header_level(node));
128 btrfs_set_root_generation(item, btrfs_header_generation(node));
5d4f98a2
YZ
129}
130
d352ac68
CM
131/*
132 * copy the data in 'item' into the btree
133 */
e089f05c
CM
134int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
135 *root, struct btrfs_key *key, struct btrfs_root_item
136 *item)
3768f368 137{
5caf2a00 138 struct btrfs_path *path;
5f39d397 139 struct extent_buffer *l;
3768f368
CM
140 int ret;
141 int slot;
5f39d397 142 unsigned long ptr;
8ea05e3a 143 int old_len;
3768f368 144
5caf2a00 145 path = btrfs_alloc_path();
b45a9d8b
JM
146 if (!path)
147 return -ENOMEM;
148
5caf2a00 149 ret = btrfs_search_slot(trans, root, key, path, 0, 1);
005d6427
DS
150 if (ret < 0) {
151 btrfs_abort_transaction(trans, root, ret);
152 goto out;
153 }
d6667462
CM
154
155 if (ret != 0) {
156 btrfs_print_leaf(root, path->nodes[0]);
d397712b
CM
157 printk(KERN_CRIT "unable to update root key %llu %u %llu\n",
158 (unsigned long long)key->objectid, key->type,
159 (unsigned long long)key->offset);
d6667462
CM
160 BUG_ON(1);
161 }
162
5f39d397 163 l = path->nodes[0];
5caf2a00 164 slot = path->slots[0];
5f39d397 165 ptr = btrfs_item_ptr_offset(l, slot);
8ea05e3a
AB
166 old_len = btrfs_item_size_nr(l, slot);
167
168 /*
169 * If this is the first time we update the root item which originated
170 * from an older kernel, we need to enlarge the item size to make room
171 * for the added fields.
172 */
173 if (old_len < sizeof(*item)) {
174 btrfs_release_path(path);
175 ret = btrfs_search_slot(trans, root, key, path,
176 -1, 1);
005d6427
DS
177 if (ret < 0) {
178 btrfs_abort_transaction(trans, root, ret);
179 goto out;
180 }
181
8ea05e3a 182 ret = btrfs_del_item(trans, root, path);
005d6427
DS
183 if (ret < 0) {
184 btrfs_abort_transaction(trans, root, ret);
185 goto out;
186 }
8ea05e3a
AB
187 btrfs_release_path(path);
188 ret = btrfs_insert_empty_item(trans, root, path,
189 key, sizeof(*item));
005d6427
DS
190 if (ret < 0) {
191 btrfs_abort_transaction(trans, root, ret);
192 goto out;
193 }
8ea05e3a
AB
194 l = path->nodes[0];
195 slot = path->slots[0];
196 ptr = btrfs_item_ptr_offset(l, slot);
197 }
198
199 /*
200 * Update generation_v2 so at the next mount we know the new root
201 * fields are valid.
202 */
203 btrfs_set_root_generation_v2(item, btrfs_root_generation(item));
204
5f39d397 205 write_extent_buffer(l, item, ptr, sizeof(*item));
5caf2a00 206 btrfs_mark_buffer_dirty(path->nodes[0]);
3768f368 207out:
5caf2a00 208 btrfs_free_path(path);
3768f368
CM
209 return ret;
210}
211
d16cb050
JM
212int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
213 struct btrfs_key *key, struct btrfs_root_item *item)
3768f368 214{
8ea05e3a
AB
215 /*
216 * Make sure generation v1 and v2 match. See update_root for details.
217 */
218 btrfs_set_root_generation_v2(item, btrfs_root_generation(item));
d16cb050 219 return btrfs_insert_item(trans, root, key, item, sizeof(*item));
3768f368
CM
220}
221
76dda93c
YZ
222int btrfs_find_orphan_roots(struct btrfs_root *tree_root)
223{
224 struct extent_buffer *leaf;
225 struct btrfs_path *path;
226 struct btrfs_key key;
d68fc57b
YZ
227 struct btrfs_key root_key;
228 struct btrfs_root *root;
76dda93c
YZ
229 int err = 0;
230 int ret;
68a7342c
JB
231 bool can_recover = true;
232
233 if (tree_root->fs_info->sb->s_flags & MS_RDONLY)
234 can_recover = false;
76dda93c
YZ
235
236 path = btrfs_alloc_path();
237 if (!path)
238 return -ENOMEM;
239
240 key.objectid = BTRFS_ORPHAN_OBJECTID;
241 key.type = BTRFS_ORPHAN_ITEM_KEY;
242 key.offset = 0;
243
d68fc57b
YZ
244 root_key.type = BTRFS_ROOT_ITEM_KEY;
245 root_key.offset = (u64)-1;
246
76dda93c
YZ
247 while (1) {
248 ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
249 if (ret < 0) {
250 err = ret;
251 break;
252 }
253
254 leaf = path->nodes[0];
255 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
256 ret = btrfs_next_leaf(tree_root, path);
257 if (ret < 0)
258 err = ret;
259 if (ret != 0)
260 break;
261 leaf = path->nodes[0];
262 }
263
264 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
b3b4aa74 265 btrfs_release_path(path);
76dda93c
YZ
266
267 if (key.objectid != BTRFS_ORPHAN_OBJECTID ||
268 key.type != BTRFS_ORPHAN_ITEM_KEY)
269 break;
270
d68fc57b
YZ
271 root_key.objectid = key.offset;
272 key.offset++;
273
cb517eab 274 root = btrfs_read_fs_root(tree_root, &root_key);
68a7342c
JB
275 err = PTR_RET(root);
276 if (err && err != -ENOENT) {
cb517eab 277 break;
68a7342c
JB
278 } else if (err == -ENOENT) {
279 struct btrfs_trans_handle *trans;
280
281 btrfs_release_path(path);
282
283 trans = btrfs_join_transaction(tree_root);
284 if (IS_ERR(trans)) {
285 err = PTR_ERR(trans);
286 btrfs_error(tree_root->fs_info, err,
287 "Failed to start trans to delete "
288 "orphan item");
289 break;
290 }
291 err = btrfs_del_orphan_item(trans, tree_root,
292 root_key.objectid);
293 btrfs_end_transaction(trans, tree_root);
294 if (err) {
295 btrfs_error(tree_root->fs_info, err,
296 "Failed to delete root orphan "
297 "item");
298 break;
299 }
300 continue;
cb517eab
MX
301 }
302
303 if (btrfs_root_refs(&root->root_item) == 0) {
304 btrfs_add_dead_root(root);
d68fc57b 305 continue;
cb517eab 306 }
d68fc57b 307
cb517eab
MX
308 err = btrfs_init_fs_root(root);
309 if (err) {
310 btrfs_free_fs_root(root);
76dda93c
YZ
311 break;
312 }
313
cb517eab
MX
314 root->orphan_item_inserted = 1;
315
316 err = btrfs_insert_fs_root(root->fs_info, root);
317 if (err) {
318 BUG_ON(err == -EEXIST);
319 btrfs_free_fs_root(root);
d68fc57b
YZ
320 break;
321 }
76dda93c
YZ
322 }
323
324 btrfs_free_path(path);
325 return err;
326}
327
d352ac68 328/* drop the root item for 'key' from 'root' */
e089f05c
CM
329int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
330 struct btrfs_key *key)
3768f368 331{
5caf2a00 332 struct btrfs_path *path;
3768f368
CM
333 int ret;
334
5caf2a00 335 path = btrfs_alloc_path();
db5b493a
TI
336 if (!path)
337 return -ENOMEM;
5caf2a00 338 ret = btrfs_search_slot(trans, root, key, path, -1, 1);
3768f368
CM
339 if (ret < 0)
340 goto out;
edbd8d4e 341
3768f368 342 BUG_ON(ret != 0);
c5739bba 343
5eda7b5e 344 ret = btrfs_del_item(trans, root, path);
3768f368 345out:
5caf2a00 346 btrfs_free_path(path);
3768f368
CM
347 return ret;
348}
0660b5af
CM
349
350int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
351 struct btrfs_root *tree_root,
4df27c4d
YZ
352 u64 root_id, u64 ref_id, u64 dirid, u64 *sequence,
353 const char *name, int name_len)
354
0660b5af 355{
4df27c4d
YZ
356 struct btrfs_path *path;
357 struct btrfs_root_ref *ref;
358 struct extent_buffer *leaf;
0660b5af 359 struct btrfs_key key;
4df27c4d
YZ
360 unsigned long ptr;
361 int err = 0;
0660b5af 362 int ret;
0660b5af
CM
363
364 path = btrfs_alloc_path();
4df27c4d
YZ
365 if (!path)
366 return -ENOMEM;
0660b5af
CM
367
368 key.objectid = root_id;
4df27c4d 369 key.type = BTRFS_ROOT_BACKREF_KEY;
0660b5af 370 key.offset = ref_id;
4df27c4d 371again:
0660b5af 372 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
4df27c4d
YZ
373 BUG_ON(ret < 0);
374 if (ret == 0) {
375 leaf = path->nodes[0];
376 ref = btrfs_item_ptr(leaf, path->slots[0],
377 struct btrfs_root_ref);
378
379 WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid);
380 WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len);
381 ptr = (unsigned long)(ref + 1);
382 WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len));
383 *sequence = btrfs_root_ref_sequence(leaf, ref);
384
385 ret = btrfs_del_item(trans, tree_root, path);
65a246c5
TI
386 if (ret) {
387 err = ret;
388 goto out;
389 }
4df27c4d
YZ
390 } else
391 err = -ENOENT;
392
393 if (key.type == BTRFS_ROOT_BACKREF_KEY) {
b3b4aa74 394 btrfs_release_path(path);
4df27c4d
YZ
395 key.objectid = ref_id;
396 key.type = BTRFS_ROOT_REF_KEY;
397 key.offset = root_id;
398 goto again;
399 }
0660b5af 400
65a246c5 401out:
0660b5af 402 btrfs_free_path(path);
4df27c4d 403 return err;
0660b5af
CM
404}
405
ea9e8b11
CM
406int btrfs_find_root_ref(struct btrfs_root *tree_root,
407 struct btrfs_path *path,
408 u64 root_id, u64 ref_id)
409{
410 struct btrfs_key key;
411 int ret;
412
413 key.objectid = root_id;
414 key.type = BTRFS_ROOT_REF_KEY;
415 key.offset = ref_id;
416
417 ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
418 return ret;
419}
420
0660b5af
CM
421/*
422 * add a btrfs_root_ref item. type is either BTRFS_ROOT_REF_KEY
423 * or BTRFS_ROOT_BACKREF_KEY.
424 *
425 * The dirid, sequence, name and name_len refer to the directory entry
426 * that is referencing the root.
427 *
428 * For a forward ref, the root_id is the id of the tree referencing
429 * the root and ref_id is the id of the subvol or snapshot.
430 *
431 * For a back ref the root_id is the id of the subvol or snapshot and
432 * ref_id is the id of the tree referencing it.
79787eaa
JM
433 *
434 * Will return 0, -ENOMEM, or anything from the CoW path
0660b5af
CM
435 */
436int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
437 struct btrfs_root *tree_root,
4df27c4d 438 u64 root_id, u64 ref_id, u64 dirid, u64 sequence,
0660b5af
CM
439 const char *name, int name_len)
440{
441 struct btrfs_key key;
442 int ret;
443 struct btrfs_path *path;
444 struct btrfs_root_ref *ref;
445 struct extent_buffer *leaf;
446 unsigned long ptr;
447
0660b5af 448 path = btrfs_alloc_path();
4df27c4d
YZ
449 if (!path)
450 return -ENOMEM;
0660b5af
CM
451
452 key.objectid = root_id;
4df27c4d 453 key.type = BTRFS_ROOT_BACKREF_KEY;
0660b5af 454 key.offset = ref_id;
4df27c4d 455again:
0660b5af
CM
456 ret = btrfs_insert_empty_item(trans, tree_root, path, &key,
457 sizeof(*ref) + name_len);
79787eaa
JM
458 if (ret) {
459 btrfs_abort_transaction(trans, tree_root, ret);
460 btrfs_free_path(path);
461 return ret;
462 }
0660b5af
CM
463
464 leaf = path->nodes[0];
465 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
466 btrfs_set_root_ref_dirid(leaf, ref, dirid);
467 btrfs_set_root_ref_sequence(leaf, ref, sequence);
468 btrfs_set_root_ref_name_len(leaf, ref, name_len);
469 ptr = (unsigned long)(ref + 1);
470 write_extent_buffer(leaf, name, ptr, name_len);
471 btrfs_mark_buffer_dirty(leaf);
472
4df27c4d 473 if (key.type == BTRFS_ROOT_BACKREF_KEY) {
b3b4aa74 474 btrfs_release_path(path);
4df27c4d
YZ
475 key.objectid = ref_id;
476 key.type = BTRFS_ROOT_REF_KEY;
477 key.offset = root_id;
478 goto again;
479 }
480
0660b5af 481 btrfs_free_path(path);
4df27c4d 482 return 0;
0660b5af 483}
08fe4db1
LZ
484
485/*
486 * Old btrfs forgets to init root_item->flags and root_item->byte_limit
487 * for subvolumes. To work around this problem, we steal a bit from
488 * root_item->inode_item->flags, and use it to indicate if those fields
489 * have been properly initialized.
490 */
491void btrfs_check_and_init_root_item(struct btrfs_root_item *root_item)
492{
3cae210f 493 u64 inode_flags = btrfs_stack_inode_flags(&root_item->inode);
08fe4db1
LZ
494
495 if (!(inode_flags & BTRFS_INODE_ROOT_ITEM_INIT)) {
496 inode_flags |= BTRFS_INODE_ROOT_ITEM_INIT;
3cae210f
QW
497 btrfs_set_stack_inode_flags(&root_item->inode, inode_flags);
498 btrfs_set_root_flags(root_item, 0);
499 btrfs_set_root_limit(root_item, 0);
08fe4db1
LZ
500 }
501}
8ea05e3a
AB
502
503void btrfs_update_root_times(struct btrfs_trans_handle *trans,
504 struct btrfs_root *root)
505{
506 struct btrfs_root_item *item = &root->root_item;
507 struct timespec ct = CURRENT_TIME;
508
5f3ab90a 509 spin_lock(&root->root_item_lock);
3cae210f
QW
510 btrfs_set_root_ctransid(item, trans->transid);
511 btrfs_set_stack_timespec_sec(&item->ctime, ct.tv_sec);
512 btrfs_set_stack_timespec_nsec(&item->ctime, ct.tv_nsec);
5f3ab90a 513 spin_unlock(&root->root_item_lock);
8ea05e3a 514}