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mm: compaction: determine if dirty pages can be migrated without blocking within...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / btrfs / disk-io.c
blob1375494c8cb60c691a555b947f022bb8d0a439a7
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
19 #include <linux/fs.h>
20 #include <linux/blkdev.h>
21 #include <linux/scatterlist.h>
22 #include <linux/swap.h>
23 #include <linux/radix-tree.h>
24 #include <linux/writeback.h>
25 #include <linux/buffer_head.h>
26 #include <linux/workqueue.h>
27 #include <linux/kthread.h>
28 #include <linux/freezer.h>
29 #include <linux/crc32c.h>
30 #include <linux/slab.h>
31 #include <linux/migrate.h>
32 #include <linux/ratelimit.h>
33 #include <asm/unaligned.h>
34 #include "compat.h"
35 #include "ctree.h"
36 #include "disk-io.h"
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "volumes.h"
40 #include "print-tree.h"
41 #include "async-thread.h"
42 #include "locking.h"
43 #include "tree-log.h"
44 #include "free-space-cache.h"
45 #include "inode-map.h"
46
47 static struct extent_io_ops btree_extent_io_ops;
48 static void end_workqueue_fn(struct btrfs_work *work);
49 static void free_fs_root(struct btrfs_root *root);
50 static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
51 int read_only);
52 static int btrfs_destroy_ordered_operations(struct btrfs_root *root);
53 static int btrfs_destroy_ordered_extents(struct btrfs_root *root);
54 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
55 struct btrfs_root *root);
56 static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
57 static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
58 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
59 struct extent_io_tree *dirty_pages,
60 int mark);
61 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
62 struct extent_io_tree *pinned_extents);
63 static int btrfs_cleanup_transaction(struct btrfs_root *root);
64
65 /*
66 * end_io_wq structs are used to do processing in task context when an IO is
67 * complete. This is used during reads to verify checksums, and it is used
68 * by writes to insert metadata for new file extents after IO is complete.
69 */
70 struct end_io_wq {
71 struct bio *bio;
72 bio_end_io_t *end_io;
73 void *private;
74 struct btrfs_fs_info *info;
75 int error;
76 int metadata;
77 struct list_head list;
78 struct btrfs_work work;
79 };
80
81 /*
82 * async submit bios are used to offload expensive checksumming
83 * onto the worker threads. They checksum file and metadata bios
84 * just before they are sent down the IO stack.
85 */
86 struct async_submit_bio {
87 struct inode *inode;
88 struct bio *bio;
89 struct list_head list;
90 extent_submit_bio_hook_t *submit_bio_start;
91 extent_submit_bio_hook_t *submit_bio_done;
92 int rw;
93 int mirror_num;
94 unsigned long bio_flags;
95 /*
96 * bio_offset is optional, can be used if the pages in the bio
97 * can't tell us where in the file the bio should go
98 */
99 u64 bio_offset;
100 struct btrfs_work work;
101 };
102
103 /*
104 * Lockdep class keys for extent_buffer->lock's in this root. For a given
105 * eb, the lockdep key is determined by the btrfs_root it belongs to and
106 * the level the eb occupies in the tree.
107 *
108 * Different roots are used for different purposes and may nest inside each
109 * other and they require separate keysets. As lockdep keys should be
110 * static, assign keysets according to the purpose of the root as indicated
111 * by btrfs_root->objectid. This ensures that all special purpose roots
112 * have separate keysets.
113 *
114 * Lock-nesting across peer nodes is always done with the immediate parent
115 * node locked thus preventing deadlock. As lockdep doesn't know this, use
116 * subclass to avoid triggering lockdep warning in such cases.
117 *
118 * The key is set by the readpage_end_io_hook after the buffer has passed
119 * csum validation but before the pages are unlocked. It is also set by
120 * btrfs_init_new_buffer on freshly allocated blocks.
121 *
122 * We also add a check to make sure the highest level of the tree is the
123 * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
124 * needs update as well.
125 */
126 #ifdef CONFIG_DEBUG_LOCK_ALLOC
127 # if BTRFS_MAX_LEVEL != 8
128 # error
129 # endif
130
131 static struct btrfs_lockdep_keyset {
132 u64 id; /* root objectid */
133 const char *name_stem; /* lock name stem */
134 char names[BTRFS_MAX_LEVEL + 1][20];
135 struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
136 } btrfs_lockdep_keysets[] = {
137 { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
138 { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
139 { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
140 { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" },
141 { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
142 { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
143 { .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" },
144 { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
145 { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
146 { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
147 { .id = 0, .name_stem = "tree" },
148 };
149
150 void __init btrfs_init_lockdep(void)
151 {
152 int i, j;
153
154 /* initialize lockdep class names */
155 for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
156 struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
157
158 for (j = 0; j < ARRAY_SIZE(ks->names); j++)
159 snprintf(ks->names[j], sizeof(ks->names[j]),
160 "btrfs-%s-%02d", ks->name_stem, j);
161 }
162 }
163
164 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
165 int level)
166 {
167 struct btrfs_lockdep_keyset *ks;
168
169 BUG_ON(level >= ARRAY_SIZE(ks->keys));
170
171 /* find the matching keyset, id 0 is the default entry */
172 for (ks = btrfs_lockdep_keysets; ks->id; ks++)
173 if (ks->id == objectid)
174 break;
175
176 lockdep_set_class_and_name(&eb->lock,
177 &ks->keys[level], ks->names[level]);
178 }
179
180 #endif
181
182 /*
183 * extents on the btree inode are pretty simple, there's one extent
184 * that covers the entire device
185 */
186 static struct extent_map *btree_get_extent(struct inode *inode,
187 struct page *page, size_t pg_offset, u64 start, u64 len,
188 int create)
189 {
190 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
191 struct extent_map *em;
192 int ret;
193
194 read_lock(&em_tree->lock);
195 em = lookup_extent_mapping(em_tree, start, len);
196 if (em) {
197 em->bdev =
198 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
199 read_unlock(&em_tree->lock);
200 goto out;
201 }
202 read_unlock(&em_tree->lock);
203
204 em = alloc_extent_map();
205 if (!em) {
206 em = ERR_PTR(-ENOMEM);
207 goto out;
208 }
209 em->start = 0;
210 em->len = (u64)-1;
211 em->block_len = (u64)-1;
212 em->block_start = 0;
213 em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
214
215 write_lock(&em_tree->lock);
216 ret = add_extent_mapping(em_tree, em);
217 if (ret == -EEXIST) {
218 u64 failed_start = em->start;
219 u64 failed_len = em->len;
220
221 free_extent_map(em);
222 em = lookup_extent_mapping(em_tree, start, len);
223 if (em) {
224 ret = 0;
225 } else {
226 em = lookup_extent_mapping(em_tree, failed_start,
227 failed_len);
228 ret = -EIO;
229 }
230 } else if (ret) {
231 free_extent_map(em);
232 em = NULL;
233 }
234 write_unlock(&em_tree->lock);
235
236 if (ret)
237 em = ERR_PTR(ret);
238 out:
239 return em;
240 }
241
242 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
243 {
244 return crc32c(seed, data, len);
245 }
246
247 void btrfs_csum_final(u32 crc, char *result)
248 {
249 put_unaligned_le32(~crc, result);
250 }
251
252 /*
253 * compute the csum for a btree block, and either verify it or write it
254 * into the csum field of the block.
255 */
256 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
257 int verify)
258 {
259 u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
260 char *result = NULL;
261 unsigned long len;
262 unsigned long cur_len;
263 unsigned long offset = BTRFS_CSUM_SIZE;
264 char *kaddr;
265 unsigned long map_start;
266 unsigned long map_len;
267 int err;
268 u32 crc = ~(u32)0;
269 unsigned long inline_result;
270
271 len = buf->len - offset;
272 while (len > 0) {
273 err = map_private_extent_buffer(buf, offset, 32,
274 &kaddr, &map_start, &map_len);
275 if (err)
276 return 1;
277 cur_len = min(len, map_len - (offset - map_start));
278 crc = btrfs_csum_data(root, kaddr + offset - map_start,
279 crc, cur_len);
280 len -= cur_len;
281 offset += cur_len;
282 }
283 if (csum_size > sizeof(inline_result)) {
284 result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
285 if (!result)
286 return 1;
287 } else {
288 result = (char *)&inline_result;
289 }
290
291 btrfs_csum_final(crc, result);
292
293 if (verify) {
294 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
295 u32 val;
296 u32 found = 0;
297 memcpy(&found, result, csum_size);
298
299 read_extent_buffer(buf, &val, 0, csum_size);
300 printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
301 "failed on %llu wanted %X found %X "
302 "level %d\n",
303 root->fs_info->sb->s_id,
304 (unsigned long long)buf->start, val, found,
305 btrfs_header_level(buf));
306 if (result != (char *)&inline_result)
307 kfree(result);
308 return 1;
309 }
310 } else {
311 write_extent_buffer(buf, result, 0, csum_size);
312 }
313 if (result != (char *)&inline_result)
314 kfree(result);
315 return 0;
316 }
317
318 /*
319 * we can't consider a given block up to date unless the transid of the
320 * block matches the transid in the parent node's pointer. This is how we
321 * detect blocks that either didn't get written at all or got written
322 * in the wrong place.
323 */
324 static int verify_parent_transid(struct extent_io_tree *io_tree,
325 struct extent_buffer *eb, u64 parent_transid)
326 {
327 struct extent_state *cached_state = NULL;
328 int ret;
329
330 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
331 return 0;
332
333 lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
334 0, &cached_state, GFP_NOFS);
335 if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
336 btrfs_header_generation(eb) == parent_transid) {
337 ret = 0;
338 goto out;
339 }
340 printk_ratelimited("parent transid verify failed on %llu wanted %llu "
341 "found %llu\n",
342 (unsigned long long)eb->start,
343 (unsigned long long)parent_transid,
344 (unsigned long long)btrfs_header_generation(eb));
345 ret = 1;
346 clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
347 out:
348 unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
349 &cached_state, GFP_NOFS);
350 return ret;
351 }
352
353 /*
354 * helper to read a given tree block, doing retries as required when
355 * the checksums don't match and we have alternate mirrors to try.
356 */
357 static int btree_read_extent_buffer_pages(struct btrfs_root *root,
358 struct extent_buffer *eb,
359 u64 start, u64 parent_transid)
360 {
361 struct extent_io_tree *io_tree;
362 int ret;
363 int num_copies = 0;
364 int mirror_num = 0;
365
366 clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
367 io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
368 while (1) {
369 ret = read_extent_buffer_pages(io_tree, eb, start,
370 WAIT_COMPLETE,
371 btree_get_extent, mirror_num);
372 if (!ret &&
373 !verify_parent_transid(io_tree, eb, parent_transid))
374 return ret;
375
376 /*
377 * This buffer's crc is fine, but its contents are corrupted, so
378 * there is no reason to read the other copies, they won't be
379 * any less wrong.
380 */
381 if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
382 return ret;
383
384 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
385 eb->start, eb->len);
386 if (num_copies == 1)
387 return ret;
388
389 mirror_num++;
390 if (mirror_num > num_copies)
391 return ret;
392 }
393 return -EIO;
394 }
395
396 /*
397 * checksum a dirty tree block before IO. This has extra checks to make sure
398 * we only fill in the checksum field in the first page of a multi-page block
399 */
400
401 static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
402 {
403 struct extent_io_tree *tree;
404 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
405 u64 found_start;
406 unsigned long len;
407 struct extent_buffer *eb;
408 int ret;
409
410 tree = &BTRFS_I(page->mapping->host)->io_tree;
411
412 if (page->private == EXTENT_PAGE_PRIVATE) {
413 WARN_ON(1);
414 goto out;
415 }
416 if (!page->private) {
417 WARN_ON(1);
418 goto out;
419 }
420 len = page->private >> 2;
421 WARN_ON(len == 0);
422
423 eb = alloc_extent_buffer(tree, start, len, page);
424 if (eb == NULL) {
425 WARN_ON(1);
426 goto out;
427 }
428 ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
429 btrfs_header_generation(eb));
430 BUG_ON(ret);
431 WARN_ON(!btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN));
432
433 found_start = btrfs_header_bytenr(eb);
434 if (found_start != start) {
435 WARN_ON(1);
436 goto err;
437 }
438 if (eb->first_page != page) {
439 WARN_ON(1);
440 goto err;
441 }
442 if (!PageUptodate(page)) {
443 WARN_ON(1);
444 goto err;
445 }
446 csum_tree_block(root, eb, 0);
447 err:
448 free_extent_buffer(eb);
449 out:
450 return 0;
451 }
452
453 static int check_tree_block_fsid(struct btrfs_root *root,
454 struct extent_buffer *eb)
455 {
456 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
457 u8 fsid[BTRFS_UUID_SIZE];
458 int ret = 1;
459
460 read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
461 BTRFS_FSID_SIZE);
462 while (fs_devices) {
463 if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
464 ret = 0;
465 break;
466 }
467 fs_devices = fs_devices->seed;
468 }
469 return ret;
470 }
471
472 #define CORRUPT(reason, eb, root, slot) \
473 printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu," \
474 "root=%llu, slot=%d\n", reason, \
475 (unsigned long long)btrfs_header_bytenr(eb), \
476 (unsigned long long)root->objectid, slot)
477
478 static noinline int check_leaf(struct btrfs_root *root,
479 struct extent_buffer *leaf)
480 {
481 struct btrfs_key key;
482 struct btrfs_key leaf_key;
483 u32 nritems = btrfs_header_nritems(leaf);
484 int slot;
485
486 if (nritems == 0)
487 return 0;
488
489 /* Check the 0 item */
490 if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
491 BTRFS_LEAF_DATA_SIZE(root)) {
492 CORRUPT("invalid item offset size pair", leaf, root, 0);
493 return -EIO;
494 }
495
496 /*
497 * Check to make sure each items keys are in the correct order and their
498 * offsets make sense. We only have to loop through nritems-1 because
499 * we check the current slot against the next slot, which verifies the
500 * next slot's offset+size makes sense and that the current's slot
501 * offset is correct.
502 */
503 for (slot = 0; slot < nritems - 1; slot++) {
504 btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
505 btrfs_item_key_to_cpu(leaf, &key, slot + 1);
506
507 /* Make sure the keys are in the right order */
508 if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
509 CORRUPT("bad key order", leaf, root, slot);
510 return -EIO;
511 }
512
513 /*
514 * Make sure the offset and ends are right, remember that the
515 * item data starts at the end of the leaf and grows towards the
516 * front.
517 */
518 if (btrfs_item_offset_nr(leaf, slot) !=
519 btrfs_item_end_nr(leaf, slot + 1)) {
520 CORRUPT("slot offset bad", leaf, root, slot);
521 return -EIO;
522 }
523
524 /*
525 * Check to make sure that we don't point outside of the leaf,
526 * just incase all the items are consistent to eachother, but
527 * all point outside of the leaf.
528 */
529 if (btrfs_item_end_nr(leaf, slot) >
530 BTRFS_LEAF_DATA_SIZE(root)) {
531 CORRUPT("slot end outside of leaf", leaf, root, slot);
532 return -EIO;
533 }
534 }
535
536 return 0;
537 }
538
539 static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
540 struct extent_state *state)
541 {
542 struct extent_io_tree *tree;
543 u64 found_start;
544 int found_level;
545 unsigned long len;
546 struct extent_buffer *eb;
547 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
548 int ret = 0;
549
550 tree = &BTRFS_I(page->mapping->host)->io_tree;
551 if (page->private == EXTENT_PAGE_PRIVATE)
552 goto out;
553 if (!page->private)
554 goto out;
555
556 len = page->private >> 2;
557 WARN_ON(len == 0);
558
559 eb = alloc_extent_buffer(tree, start, len, page);
560 if (eb == NULL) {
561 ret = -EIO;
562 goto out;
563 }
564
565 found_start = btrfs_header_bytenr(eb);
566 if (found_start != start) {
567 printk_ratelimited(KERN_INFO "btrfs bad tree block start "
568 "%llu %llu\n",
569 (unsigned long long)found_start,
570 (unsigned long long)eb->start);
571 ret = -EIO;
572 goto err;
573 }
574 if (eb->first_page != page) {
575 printk(KERN_INFO "btrfs bad first page %lu %lu\n",
576 eb->first_page->index, page->index);
577 WARN_ON(1);
578 ret = -EIO;
579 goto err;
580 }
581 if (check_tree_block_fsid(root, eb)) {
582 printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
583 (unsigned long long)eb->start);
584 ret = -EIO;
585 goto err;
586 }
587 found_level = btrfs_header_level(eb);
588
589 btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
590 eb, found_level);
591
592 ret = csum_tree_block(root, eb, 1);
593 if (ret) {
594 ret = -EIO;
595 goto err;
596 }
597
598 /*
599 * If this is a leaf block and it is corrupt, set the corrupt bit so
600 * that we don't try and read the other copies of this block, just
601 * return -EIO.
602 */
603 if (found_level == 0 && check_leaf(root, eb)) {
604 set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
605 ret = -EIO;
606 }
607
608 end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
609 end = eb->start + end - 1;
610 err:
611 if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
612 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
613 btree_readahead_hook(root, eb, eb->start, ret);
614 }
615
616 free_extent_buffer(eb);
617 out:
618 return ret;
619 }
620
621 static int btree_io_failed_hook(struct bio *failed_bio,
622 struct page *page, u64 start, u64 end,
623 int mirror_num, struct extent_state *state)
624 {
625 struct extent_io_tree *tree;
626 unsigned long len;
627 struct extent_buffer *eb;
628 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
629
630 tree = &BTRFS_I(page->mapping->host)->io_tree;
631 if (page->private == EXTENT_PAGE_PRIVATE)
632 goto out;
633 if (!page->private)
634 goto out;
635
636 len = page->private >> 2;
637 WARN_ON(len == 0);
638
639 eb = alloc_extent_buffer(tree, start, len, page);
640 if (eb == NULL)
641 goto out;
642
643 if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
644 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
645 btree_readahead_hook(root, eb, eb->start, -EIO);
646 }
647 free_extent_buffer(eb);
648
649 out:
650 return -EIO; /* we fixed nothing */
651 }
652
653 static void end_workqueue_bio(struct bio *bio, int err)
654 {
655 struct end_io_wq *end_io_wq = bio->bi_private;
656 struct btrfs_fs_info *fs_info;
657
658 fs_info = end_io_wq->info;
659 end_io_wq->error = err;
660 end_io_wq->work.func = end_workqueue_fn;
661 end_io_wq->work.flags = 0;
662
663 if (bio->bi_rw & REQ_WRITE) {
664 if (end_io_wq->metadata == 1)
665 btrfs_queue_worker(&fs_info->endio_meta_write_workers,
666 &end_io_wq->work);
667 else if (end_io_wq->metadata == 2)
668 btrfs_queue_worker(&fs_info->endio_freespace_worker,
669 &end_io_wq->work);
670 else
671 btrfs_queue_worker(&fs_info->endio_write_workers,
672 &end_io_wq->work);
673 } else {
674 if (end_io_wq->metadata)
675 btrfs_queue_worker(&fs_info->endio_meta_workers,
676 &end_io_wq->work);
677 else
678 btrfs_queue_worker(&fs_info->endio_workers,
679 &end_io_wq->work);
680 }
681 }
682
683 /*
684 * For the metadata arg you want
685 *
686 * 0 - if data
687 * 1 - if normal metadta
688 * 2 - if writing to the free space cache area
689 */
690 int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
691 int metadata)
692 {
693 struct end_io_wq *end_io_wq;
694 end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
695 if (!end_io_wq)
696 return -ENOMEM;
697
698 end_io_wq->private = bio->bi_private;
699 end_io_wq->end_io = bio->bi_end_io;
700 end_io_wq->info = info;
701 end_io_wq->error = 0;
702 end_io_wq->bio = bio;
703 end_io_wq->metadata = metadata;
704
705 bio->bi_private = end_io_wq;
706 bio->bi_end_io = end_workqueue_bio;
707 return 0;
708 }
709
710 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
711 {
712 unsigned long limit = min_t(unsigned long,
713 info->workers.max_workers,
714 info->fs_devices->open_devices);
715 return 256 * limit;
716 }
717
718 static void run_one_async_start(struct btrfs_work *work)
719 {
720 struct async_submit_bio *async;
721
722 async = container_of(work, struct async_submit_bio, work);
723 async->submit_bio_start(async->inode, async->rw, async->bio,
724 async->mirror_num, async->bio_flags,
725 async->bio_offset);
726 }
727
728 static void run_one_async_done(struct btrfs_work *work)
729 {
730 struct btrfs_fs_info *fs_info;
731 struct async_submit_bio *async;
732 int limit;
733
734 async = container_of(work, struct async_submit_bio, work);
735 fs_info = BTRFS_I(async->inode)->root->fs_info;
736
737 limit = btrfs_async_submit_limit(fs_info);
738 limit = limit * 2 / 3;
739
740 atomic_dec(&fs_info->nr_async_submits);
741
742 if (atomic_read(&fs_info->nr_async_submits) < limit &&
743 waitqueue_active(&fs_info->async_submit_wait))
744 wake_up(&fs_info->async_submit_wait);
745
746 async->submit_bio_done(async->inode, async->rw, async->bio,
747 async->mirror_num, async->bio_flags,
748 async->bio_offset);
749 }
750
751 static void run_one_async_free(struct btrfs_work *work)
752 {
753 struct async_submit_bio *async;
754
755 async = container_of(work, struct async_submit_bio, work);
756 kfree(async);
757 }
758
759 int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
760 int rw, struct bio *bio, int mirror_num,
761 unsigned long bio_flags,
762 u64 bio_offset,
763 extent_submit_bio_hook_t *submit_bio_start,
764 extent_submit_bio_hook_t *submit_bio_done)
765 {
766 struct async_submit_bio *async;
767
768 async = kmalloc(sizeof(*async), GFP_NOFS);
769 if (!async)
770 return -ENOMEM;
771
772 async->inode = inode;
773 async->rw = rw;
774 async->bio = bio;
775 async->mirror_num = mirror_num;
776 async->submit_bio_start = submit_bio_start;
777 async->submit_bio_done = submit_bio_done;
778
779 async->work.func = run_one_async_start;
780 async->work.ordered_func = run_one_async_done;
781 async->work.ordered_free = run_one_async_free;
782
783 async->work.flags = 0;
784 async->bio_flags = bio_flags;
785 async->bio_offset = bio_offset;
786
787 atomic_inc(&fs_info->nr_async_submits);
788
789 if (rw & REQ_SYNC)
790 btrfs_set_work_high_prio(&async->work);
791
792 btrfs_queue_worker(&fs_info->workers, &async->work);
793
794 while (atomic_read(&fs_info->async_submit_draining) &&
795 atomic_read(&fs_info->nr_async_submits)) {
796 wait_event(fs_info->async_submit_wait,
797 (atomic_read(&fs_info->nr_async_submits) == 0));
798 }
799
800 return 0;
801 }
802
803 static int btree_csum_one_bio(struct bio *bio)
804 {
805 struct bio_vec *bvec = bio->bi_io_vec;
806 int bio_index = 0;
807 struct btrfs_root *root;
808
809 WARN_ON(bio->bi_vcnt <= 0);
810 while (bio_index < bio->bi_vcnt) {
811 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
812 csum_dirty_buffer(root, bvec->bv_page);
813 bio_index++;
814 bvec++;
815 }
816 return 0;
817 }
818
819 static int __btree_submit_bio_start(struct inode *inode, int rw,
820 struct bio *bio, int mirror_num,
821 unsigned long bio_flags,
822 u64 bio_offset)
823 {
824 /*
825 * when we're called for a write, we're already in the async
826 * submission context. Just jump into btrfs_map_bio
827 */
828 btree_csum_one_bio(bio);
829 return 0;
830 }
831
832 static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
833 int mirror_num, unsigned long bio_flags,
834 u64 bio_offset)
835 {
836 /*
837 * when we're called for a write, we're already in the async
838 * submission context. Just jump into btrfs_map_bio
839 */
840 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
841 }
842
843 static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
844 int mirror_num, unsigned long bio_flags,
845 u64 bio_offset)
846 {
847 int ret;
848
849 ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
850 bio, 1);
851 BUG_ON(ret);
852
853 if (!(rw & REQ_WRITE)) {
854 /*
855 * called for a read, do the setup so that checksum validation
856 * can happen in the async kernel threads
857 */
858 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
859 mirror_num, 0);
860 }
861
862 /*
863 * kthread helpers are used to submit writes so that checksumming
864 * can happen in parallel across all CPUs
865 */
866 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
867 inode, rw, bio, mirror_num, 0,
868 bio_offset,
869 __btree_submit_bio_start,
870 __btree_submit_bio_done);
871 }
872
873 #ifdef CONFIG_MIGRATION
874 static int btree_migratepage(struct address_space *mapping,
875 struct page *newpage, struct page *page, bool sync)
876 {
877 /*
878 * we can't safely write a btree page from here,
879 * we haven't done the locking hook
880 */
881 if (PageDirty(page))
882 return -EAGAIN;
883 /*
884 * Buffers may be managed in a filesystem specific way.
885 * We must have no buffers or drop them.
886 */
887 if (page_has_private(page) &&
888 !try_to_release_page(page, GFP_KERNEL))
889 return -EAGAIN;
890 return migrate_page(mapping, newpage, page, sync);
891 }
892 #endif
893
894 static int btree_writepage(struct page *page, struct writeback_control *wbc)
895 {
896 struct extent_io_tree *tree;
897 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
898 struct extent_buffer *eb;
899 int was_dirty;
900
901 tree = &BTRFS_I(page->mapping->host)->io_tree;
902 if (!(current->flags & PF_MEMALLOC)) {
903 return extent_write_full_page(tree, page,
904 btree_get_extent, wbc);
905 }
906
907 redirty_page_for_writepage(wbc, page);
908 eb = btrfs_find_tree_block(root, page_offset(page), PAGE_CACHE_SIZE);
909 WARN_ON(!eb);
910
911 was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
912 if (!was_dirty) {
913 spin_lock(&root->fs_info->delalloc_lock);
914 root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
915 spin_unlock(&root->fs_info->delalloc_lock);
916 }
917 free_extent_buffer(eb);
918
919 unlock_page(page);
920 return 0;
921 }
922
923 static int btree_writepages(struct address_space *mapping,
924 struct writeback_control *wbc)
925 {
926 struct extent_io_tree *tree;
927 tree = &BTRFS_I(mapping->host)->io_tree;
928 if (wbc->sync_mode == WB_SYNC_NONE) {
929 struct btrfs_root *root = BTRFS_I(mapping->host)->root;
930 u64 num_dirty;
931 unsigned long thresh = 32 * 1024 * 1024;
932
933 if (wbc->for_kupdate)
934 return 0;
935
936 /* this is a bit racy, but that's ok */
937 num_dirty = root->fs_info->dirty_metadata_bytes;
938 if (num_dirty < thresh)
939 return 0;
940 }
941 return extent_writepages(tree, mapping, btree_get_extent, wbc);
942 }
943
944 static int btree_readpage(struct file *file, struct page *page)
945 {
946 struct extent_io_tree *tree;
947 tree = &BTRFS_I(page->mapping->host)->io_tree;
948 return extent_read_full_page(tree, page, btree_get_extent, 0);
949 }
950
951 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
952 {
953 struct extent_io_tree *tree;
954 struct extent_map_tree *map;
955 int ret;
956
957 if (PageWriteback(page) || PageDirty(page))
958 return 0;
959
960 tree = &BTRFS_I(page->mapping->host)->io_tree;
961 map = &BTRFS_I(page->mapping->host)->extent_tree;
962
963 ret = try_release_extent_state(map, tree, page, gfp_flags);
964 if (!ret)
965 return 0;
966
967 ret = try_release_extent_buffer(tree, page);
968 if (ret == 1) {
969 ClearPagePrivate(page);
970 set_page_private(page, 0);
971 page_cache_release(page);
972 }
973
974 return ret;
975 }
976
977 static void btree_invalidatepage(struct page *page, unsigned long offset)
978 {
979 struct extent_io_tree *tree;
980 tree = &BTRFS_I(page->mapping->host)->io_tree;
981 extent_invalidatepage(tree, page, offset);
982 btree_releasepage(page, GFP_NOFS);
983 if (PagePrivate(page)) {
984 printk(KERN_WARNING "btrfs warning page private not zero "
985 "on page %llu\n", (unsigned long long)page_offset(page));
986 ClearPagePrivate(page);
987 set_page_private(page, 0);
988 page_cache_release(page);
989 }
990 }
991
992 static const struct address_space_operations btree_aops = {
993 .readpage = btree_readpage,
994 .writepage = btree_writepage,
995 .writepages = btree_writepages,
996 .releasepage = btree_releasepage,
997 .invalidatepage = btree_invalidatepage,
998 #ifdef CONFIG_MIGRATION
999 .migratepage = btree_migratepage,
1000 #endif
1001 };
1002
1003 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1004 u64 parent_transid)
1005 {
1006 struct extent_buffer *buf = NULL;
1007 struct inode *btree_inode = root->fs_info->btree_inode;
1008 int ret = 0;
1009
1010 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1011 if (!buf)
1012 return 0;
1013 read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1014 buf, 0, WAIT_NONE, btree_get_extent, 0);
1015 free_extent_buffer(buf);
1016 return ret;
1017 }
1018
1019 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1020 int mirror_num, struct extent_buffer **eb)
1021 {
1022 struct extent_buffer *buf = NULL;
1023 struct inode *btree_inode = root->fs_info->btree_inode;
1024 struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1025 int ret;
1026
1027 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1028 if (!buf)
1029 return 0;
1030
1031 set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1032
1033 ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1034 btree_get_extent, mirror_num);
1035 if (ret) {
1036 free_extent_buffer(buf);
1037 return ret;
1038 }
1039
1040 if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1041 free_extent_buffer(buf);
1042 return -EIO;
1043 } else if (extent_buffer_uptodate(io_tree, buf, NULL)) {
1044 *eb = buf;
1045 } else {
1046 free_extent_buffer(buf);
1047 }
1048 return 0;
1049 }
1050
1051 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
1052 u64 bytenr, u32 blocksize)
1053 {
1054 struct inode *btree_inode = root->fs_info->btree_inode;
1055 struct extent_buffer *eb;
1056 eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1057 bytenr, blocksize);
1058 return eb;
1059 }
1060
1061 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1062 u64 bytenr, u32 blocksize)
1063 {
1064 struct inode *btree_inode = root->fs_info->btree_inode;
1065 struct extent_buffer *eb;
1066
1067 eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1068 bytenr, blocksize, NULL);
1069 return eb;
1070 }
1071
1072
1073 int btrfs_write_tree_block(struct extent_buffer *buf)
1074 {
1075 return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
1076 buf->start + buf->len - 1);
1077 }
1078
1079 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1080 {
1081 return filemap_fdatawait_range(buf->first_page->mapping,
1082 buf->start, buf->start + buf->len - 1);
1083 }
1084
1085 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1086 u32 blocksize, u64 parent_transid)
1087 {
1088 struct extent_buffer *buf = NULL;
1089 int ret;
1090
1091 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1092 if (!buf)
1093 return NULL;
1094
1095 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1096
1097 if (ret == 0)
1098 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
1099 return buf;
1100
1101 }
1102
1103 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1104 struct extent_buffer *buf)
1105 {
1106 struct inode *btree_inode = root->fs_info->btree_inode;
1107 if (btrfs_header_generation(buf) ==
1108 root->fs_info->running_transaction->transid) {
1109 btrfs_assert_tree_locked(buf);
1110
1111 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1112 spin_lock(&root->fs_info->delalloc_lock);
1113 if (root->fs_info->dirty_metadata_bytes >= buf->len)
1114 root->fs_info->dirty_metadata_bytes -= buf->len;
1115 else
1116 WARN_ON(1);
1117 spin_unlock(&root->fs_info->delalloc_lock);
1118 }
1119
1120 /* ugh, clear_extent_buffer_dirty needs to lock the page */
1121 btrfs_set_lock_blocking(buf);
1122 clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
1123 buf);
1124 }
1125 return 0;
1126 }
1127
1128 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1129 u32 stripesize, struct btrfs_root *root,
1130 struct btrfs_fs_info *fs_info,
1131 u64 objectid)
1132 {
1133 root->node = NULL;
1134 root->commit_root = NULL;
1135 root->sectorsize = sectorsize;
1136 root->nodesize = nodesize;
1137 root->leafsize = leafsize;
1138 root->stripesize = stripesize;
1139 root->ref_cows = 0;
1140 root->track_dirty = 0;
1141 root->in_radix = 0;
1142 root->orphan_item_inserted = 0;
1143 root->orphan_cleanup_state = 0;
1144
1145 root->fs_info = fs_info;
1146 root->objectid = objectid;
1147 root->last_trans = 0;
1148 root->highest_objectid = 0;
1149 root->name = NULL;
1150 root->inode_tree = RB_ROOT;
1151 INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1152 root->block_rsv = NULL;
1153 root->orphan_block_rsv = NULL;
1154
1155 INIT_LIST_HEAD(&root->dirty_list);
1156 INIT_LIST_HEAD(&root->orphan_list);
1157 INIT_LIST_HEAD(&root->root_list);
1158 spin_lock_init(&root->orphan_lock);
1159 spin_lock_init(&root->inode_lock);
1160 spin_lock_init(&root->accounting_lock);
1161 mutex_init(&root->objectid_mutex);
1162 mutex_init(&root->log_mutex);
1163 init_waitqueue_head(&root->log_writer_wait);
1164 init_waitqueue_head(&root->log_commit_wait[0]);
1165 init_waitqueue_head(&root->log_commit_wait[1]);
1166 atomic_set(&root->log_commit[0], 0);
1167 atomic_set(&root->log_commit[1], 0);
1168 atomic_set(&root->log_writers, 0);
1169 root->log_batch = 0;
1170 root->log_transid = 0;
1171 root->last_log_commit = 0;
1172 extent_io_tree_init(&root->dirty_log_pages,
1173 fs_info->btree_inode->i_mapping);
1174
1175 memset(&root->root_key, 0, sizeof(root->root_key));
1176 memset(&root->root_item, 0, sizeof(root->root_item));
1177 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1178 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1179 root->defrag_trans_start = fs_info->generation;
1180 init_completion(&root->kobj_unregister);
1181 root->defrag_running = 0;
1182 root->root_key.objectid = objectid;
1183 root->anon_dev = 0;
1184 return 0;
1185 }
1186
1187 static int find_and_setup_root(struct btrfs_root *tree_root,
1188 struct btrfs_fs_info *fs_info,
1189 u64 objectid,
1190 struct btrfs_root *root)
1191 {
1192 int ret;
1193 u32 blocksize;
1194 u64 generation;
1195
1196 __setup_root(tree_root->nodesize, tree_root->leafsize,
1197 tree_root->sectorsize, tree_root->stripesize,
1198 root, fs_info, objectid);
1199 ret = btrfs_find_last_root(tree_root, objectid,
1200 &root->root_item, &root->root_key);
1201 if (ret > 0)
1202 return -ENOENT;
1203 BUG_ON(ret);
1204
1205 generation = btrfs_root_generation(&root->root_item);
1206 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1207 root->commit_root = NULL;
1208 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1209 blocksize, generation);
1210 if (!root->node || !btrfs_buffer_uptodate(root->node, generation)) {
1211 free_extent_buffer(root->node);
1212 root->node = NULL;
1213 return -EIO;
1214 }
1215 root->commit_root = btrfs_root_node(root);
1216 return 0;
1217 }
1218
1219 static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1220 struct btrfs_fs_info *fs_info)
1221 {
1222 struct btrfs_root *root;
1223 struct btrfs_root *tree_root = fs_info->tree_root;
1224 struct extent_buffer *leaf;
1225
1226 root = kzalloc(sizeof(*root), GFP_NOFS);
1227 if (!root)
1228 return ERR_PTR(-ENOMEM);
1229
1230 __setup_root(tree_root->nodesize, tree_root->leafsize,
1231 tree_root->sectorsize, tree_root->stripesize,
1232 root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1233
1234 root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1235 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1236 root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1237 /*
1238 * log trees do not get reference counted because they go away
1239 * before a real commit is actually done. They do store pointers
1240 * to file data extents, and those reference counts still get
1241 * updated (along with back refs to the log tree).
1242 */
1243 root->ref_cows = 0;
1244
1245 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1246 BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
1247 if (IS_ERR(leaf)) {
1248 kfree(root);
1249 return ERR_CAST(leaf);
1250 }
1251
1252 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1253 btrfs_set_header_bytenr(leaf, leaf->start);
1254 btrfs_set_header_generation(leaf, trans->transid);
1255 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1256 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1257 root->node = leaf;
1258
1259 write_extent_buffer(root->node, root->fs_info->fsid,
1260 (unsigned long)btrfs_header_fsid(root->node),
1261 BTRFS_FSID_SIZE);
1262 btrfs_mark_buffer_dirty(root->node);
1263 btrfs_tree_unlock(root->node);
1264 return root;
1265 }
1266
1267 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1268 struct btrfs_fs_info *fs_info)
1269 {
1270 struct btrfs_root *log_root;
1271
1272 log_root = alloc_log_tree(trans, fs_info);
1273 if (IS_ERR(log_root))
1274 return PTR_ERR(log_root);
1275 WARN_ON(fs_info->log_root_tree);
1276 fs_info->log_root_tree = log_root;
1277 return 0;
1278 }
1279
1280 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1281 struct btrfs_root *root)
1282 {
1283 struct btrfs_root *log_root;
1284 struct btrfs_inode_item *inode_item;
1285
1286 log_root = alloc_log_tree(trans, root->fs_info);
1287 if (IS_ERR(log_root))
1288 return PTR_ERR(log_root);
1289
1290 log_root->last_trans = trans->transid;
1291 log_root->root_key.offset = root->root_key.objectid;
1292
1293 inode_item = &log_root->root_item.inode;
1294 inode_item->generation = cpu_to_le64(1);
1295 inode_item->size = cpu_to_le64(3);
1296 inode_item->nlink = cpu_to_le32(1);
1297 inode_item->nbytes = cpu_to_le64(root->leafsize);
1298 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1299
1300 btrfs_set_root_node(&log_root->root_item, log_root->node);
1301
1302 WARN_ON(root->log_root);
1303 root->log_root = log_root;
1304 root->log_transid = 0;
1305 root->last_log_commit = 0;
1306 return 0;
1307 }
1308
1309 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1310 struct btrfs_key *location)
1311 {
1312 struct btrfs_root *root;
1313 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1314 struct btrfs_path *path;
1315 struct extent_buffer *l;
1316 u64 generation;
1317 u32 blocksize;
1318 int ret = 0;
1319
1320 root = kzalloc(sizeof(*root), GFP_NOFS);
1321 if (!root)
1322 return ERR_PTR(-ENOMEM);
1323 if (location->offset == (u64)-1) {
1324 ret = find_and_setup_root(tree_root, fs_info,
1325 location->objectid, root);
1326 if (ret) {
1327 kfree(root);
1328 return ERR_PTR(ret);
1329 }
1330 goto out;
1331 }
1332
1333 __setup_root(tree_root->nodesize, tree_root->leafsize,
1334 tree_root->sectorsize, tree_root->stripesize,
1335 root, fs_info, location->objectid);
1336
1337 path = btrfs_alloc_path();
1338 if (!path) {
1339 kfree(root);
1340 return ERR_PTR(-ENOMEM);
1341 }
1342 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1343 if (ret == 0) {
1344 l = path->nodes[0];
1345 read_extent_buffer(l, &root->root_item,
1346 btrfs_item_ptr_offset(l, path->slots[0]),
1347 sizeof(root->root_item));
1348 memcpy(&root->root_key, location, sizeof(*location));
1349 }
1350 btrfs_free_path(path);
1351 if (ret) {
1352 kfree(root);
1353 if (ret > 0)
1354 ret = -ENOENT;
1355 return ERR_PTR(ret);
1356 }
1357
1358 generation = btrfs_root_generation(&root->root_item);
1359 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1360 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1361 blocksize, generation);
1362 root->commit_root = btrfs_root_node(root);
1363 BUG_ON(!root->node);
1364 out:
1365 if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
1366 root->ref_cows = 1;
1367 btrfs_check_and_init_root_item(&root->root_item);
1368 }
1369
1370 return root;
1371 }
1372
1373 struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1374 struct btrfs_key *location)
1375 {
1376 struct btrfs_root *root;
1377 int ret;
1378
1379 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1380 return fs_info->tree_root;
1381 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1382 return fs_info->extent_root;
1383 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1384 return fs_info->chunk_root;
1385 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1386 return fs_info->dev_root;
1387 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1388 return fs_info->csum_root;
1389 again:
1390 spin_lock(&fs_info->fs_roots_radix_lock);
1391 root = radix_tree_lookup(&fs_info->fs_roots_radix,
1392 (unsigned long)location->objectid);
1393 spin_unlock(&fs_info->fs_roots_radix_lock);
1394 if (root)
1395 return root;
1396
1397 root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
1398 if (IS_ERR(root))
1399 return root;
1400
1401 root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1402 root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1403 GFP_NOFS);
1404 if (!root->free_ino_pinned || !root->free_ino_ctl) {
1405 ret = -ENOMEM;
1406 goto fail;
1407 }
1408
1409 btrfs_init_free_ino_ctl(root);
1410 mutex_init(&root->fs_commit_mutex);
1411 spin_lock_init(&root->cache_lock);
1412 init_waitqueue_head(&root->cache_wait);
1413
1414 ret = get_anon_bdev(&root->anon_dev);
1415 if (ret)
1416 goto fail;
1417
1418 if (btrfs_root_refs(&root->root_item) == 0) {
1419 ret = -ENOENT;
1420 goto fail;
1421 }
1422
1423 ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
1424 if (ret < 0)
1425 goto fail;
1426 if (ret == 0)
1427 root->orphan_item_inserted = 1;
1428
1429 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1430 if (ret)
1431 goto fail;
1432
1433 spin_lock(&fs_info->fs_roots_radix_lock);
1434 ret = radix_tree_insert(&fs_info->fs_roots_radix,
1435 (unsigned long)root->root_key.objectid,
1436 root);
1437 if (ret == 0)
1438 root->in_radix = 1;
1439
1440 spin_unlock(&fs_info->fs_roots_radix_lock);
1441 radix_tree_preload_end();
1442 if (ret) {
1443 if (ret == -EEXIST) {
1444 free_fs_root(root);
1445 goto again;
1446 }
1447 goto fail;
1448 }
1449
1450 ret = btrfs_find_dead_roots(fs_info->tree_root,
1451 root->root_key.objectid);
1452 WARN_ON(ret);
1453 return root;
1454 fail:
1455 free_fs_root(root);
1456 return ERR_PTR(ret);
1457 }
1458
1459 static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1460 {
1461 struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1462 int ret = 0;
1463 struct btrfs_device *device;
1464 struct backing_dev_info *bdi;
1465
1466 rcu_read_lock();
1467 list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1468 if (!device->bdev)
1469 continue;
1470 bdi = blk_get_backing_dev_info(device->bdev);
1471 if (bdi && bdi_congested(bdi, bdi_bits)) {
1472 ret = 1;
1473 break;
1474 }
1475 }
1476 rcu_read_unlock();
1477 return ret;
1478 }
1479
1480 /*
1481 * If this fails, caller must call bdi_destroy() to get rid of the
1482 * bdi again.
1483 */
1484 static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1485 {
1486 int err;
1487
1488 bdi->capabilities = BDI_CAP_MAP_COPY;
1489 err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1490 if (err)
1491 return err;
1492
1493 bdi->ra_pages = default_backing_dev_info.ra_pages;
1494 bdi->congested_fn = btrfs_congested_fn;
1495 bdi->congested_data = info;
1496 return 0;
1497 }
1498
1499 static int bio_ready_for_csum(struct bio *bio)
1500 {
1501 u64 length = 0;
1502 u64 buf_len = 0;
1503 u64 start = 0;
1504 struct page *page;
1505 struct extent_io_tree *io_tree = NULL;
1506 struct bio_vec *bvec;
1507 int i;
1508 int ret;
1509
1510 bio_for_each_segment(bvec, bio, i) {
1511 page = bvec->bv_page;
1512 if (page->private == EXTENT_PAGE_PRIVATE) {
1513 length += bvec->bv_len;
1514 continue;
1515 }
1516 if (!page->private) {
1517 length += bvec->bv_len;
1518 continue;
1519 }
1520 length = bvec->bv_len;
1521 buf_len = page->private >> 2;
1522 start = page_offset(page) + bvec->bv_offset;
1523 io_tree = &BTRFS_I(page->mapping->host)->io_tree;
1524 }
1525 /* are we fully contained in this bio? */
1526 if (buf_len <= length)
1527 return 1;
1528
1529 ret = extent_range_uptodate(io_tree, start + length,
1530 start + buf_len - 1);
1531 return ret;
1532 }
1533
1534 /*
1535 * called by the kthread helper functions to finally call the bio end_io
1536 * functions. This is where read checksum verification actually happens
1537 */
1538 static void end_workqueue_fn(struct btrfs_work *work)
1539 {
1540 struct bio *bio;
1541 struct end_io_wq *end_io_wq;
1542 struct btrfs_fs_info *fs_info;
1543 int error;
1544
1545 end_io_wq = container_of(work, struct end_io_wq, work);
1546 bio = end_io_wq->bio;
1547 fs_info = end_io_wq->info;
1548
1549 /* metadata bio reads are special because the whole tree block must
1550 * be checksummed at once. This makes sure the entire block is in
1551 * ram and up to date before trying to verify things. For
1552 * blocksize <= pagesize, it is basically a noop
1553 */
1554 if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
1555 !bio_ready_for_csum(bio)) {
1556 btrfs_queue_worker(&fs_info->endio_meta_workers,
1557 &end_io_wq->work);
1558 return;
1559 }
1560 error = end_io_wq->error;
1561 bio->bi_private = end_io_wq->private;
1562 bio->bi_end_io = end_io_wq->end_io;
1563 kfree(end_io_wq);
1564 bio_endio(bio, error);
1565 }
1566
1567 static int cleaner_kthread(void *arg)
1568 {
1569 struct btrfs_root *root = arg;
1570
1571 do {
1572 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1573
1574 if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1575 mutex_trylock(&root->fs_info->cleaner_mutex)) {
1576 btrfs_run_delayed_iputs(root);
1577 btrfs_clean_old_snapshots(root);
1578 mutex_unlock(&root->fs_info->cleaner_mutex);
1579 btrfs_run_defrag_inodes(root->fs_info);
1580 }
1581
1582 if (!try_to_freeze()) {
1583 set_current_state(TASK_INTERRUPTIBLE);
1584 if (!kthread_should_stop())
1585 schedule();
1586 __set_current_state(TASK_RUNNING);
1587 }
1588 } while (!kthread_should_stop());
1589 return 0;
1590 }
1591
1592 static int transaction_kthread(void *arg)
1593 {
1594 struct btrfs_root *root = arg;
1595 struct btrfs_trans_handle *trans;
1596 struct btrfs_transaction *cur;
1597 u64 transid;
1598 unsigned long now;
1599 unsigned long delay;
1600 int ret;
1601
1602 do {
1603 delay = HZ * 30;
1604 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1605 mutex_lock(&root->fs_info->transaction_kthread_mutex);
1606
1607 spin_lock(&root->fs_info->trans_lock);
1608 cur = root->fs_info->running_transaction;
1609 if (!cur) {
1610 spin_unlock(&root->fs_info->trans_lock);
1611 goto sleep;
1612 }
1613
1614 now = get_seconds();
1615 if (!cur->blocked &&
1616 (now < cur->start_time || now - cur->start_time < 30)) {
1617 spin_unlock(&root->fs_info->trans_lock);
1618 delay = HZ * 5;
1619 goto sleep;
1620 }
1621 transid = cur->transid;
1622 spin_unlock(&root->fs_info->trans_lock);
1623
1624 trans = btrfs_join_transaction(root);
1625 BUG_ON(IS_ERR(trans));
1626 if (transid == trans->transid) {
1627 ret = btrfs_commit_transaction(trans, root);
1628 BUG_ON(ret);
1629 } else {
1630 btrfs_end_transaction(trans, root);
1631 }
1632 sleep:
1633 wake_up_process(root->fs_info->cleaner_kthread);
1634 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1635
1636 if (!try_to_freeze()) {
1637 set_current_state(TASK_INTERRUPTIBLE);
1638 if (!kthread_should_stop() &&
1639 !btrfs_transaction_blocked(root->fs_info))
1640 schedule_timeout(delay);
1641 __set_current_state(TASK_RUNNING);
1642 }
1643 } while (!kthread_should_stop());
1644 return 0;
1645 }
1646
1647 /*
1648 * this will find the highest generation in the array of
1649 * root backups. The index of the highest array is returned,
1650 * or -1 if we can't find anything.
1651 *
1652 * We check to make sure the array is valid by comparing the
1653 * generation of the latest root in the array with the generation
1654 * in the super block. If they don't match we pitch it.
1655 */
1656 static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1657 {
1658 u64 cur;
1659 int newest_index = -1;
1660 struct btrfs_root_backup *root_backup;
1661 int i;
1662
1663 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1664 root_backup = info->super_copy->super_roots + i;
1665 cur = btrfs_backup_tree_root_gen(root_backup);
1666 if (cur == newest_gen)
1667 newest_index = i;
1668 }
1669
1670 /* check to see if we actually wrapped around */
1671 if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1672 root_backup = info->super_copy->super_roots;
1673 cur = btrfs_backup_tree_root_gen(root_backup);
1674 if (cur == newest_gen)
1675 newest_index = 0;
1676 }
1677 return newest_index;
1678 }
1679
1680
1681 /*
1682 * find the oldest backup so we know where to store new entries
1683 * in the backup array. This will set the backup_root_index
1684 * field in the fs_info struct
1685 */
1686 static void find_oldest_super_backup(struct btrfs_fs_info *info,
1687 u64 newest_gen)
1688 {
1689 int newest_index = -1;
1690
1691 newest_index = find_newest_super_backup(info, newest_gen);
1692 /* if there was garbage in there, just move along */
1693 if (newest_index == -1) {
1694 info->backup_root_index = 0;
1695 } else {
1696 info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1697 }
1698 }
1699
1700 /*
1701 * copy all the root pointers into the super backup array.
1702 * this will bump the backup pointer by one when it is
1703 * done
1704 */
1705 static void backup_super_roots(struct btrfs_fs_info *info)
1706 {
1707 int next_backup;
1708 struct btrfs_root_backup *root_backup;
1709 int last_backup;
1710
1711 next_backup = info->backup_root_index;
1712 last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1713 BTRFS_NUM_BACKUP_ROOTS;
1714
1715 /*
1716 * just overwrite the last backup if we're at the same generation
1717 * this happens only at umount
1718 */
1719 root_backup = info->super_for_commit->super_roots + last_backup;
1720 if (btrfs_backup_tree_root_gen(root_backup) ==
1721 btrfs_header_generation(info->tree_root->node))
1722 next_backup = last_backup;
1723
1724 root_backup = info->super_for_commit->super_roots + next_backup;
1725
1726 /*
1727 * make sure all of our padding and empty slots get zero filled
1728 * regardless of which ones we use today
1729 */
1730 memset(root_backup, 0, sizeof(*root_backup));
1731
1732 info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1733
1734 btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1735 btrfs_set_backup_tree_root_gen(root_backup,
1736 btrfs_header_generation(info->tree_root->node));
1737
1738 btrfs_set_backup_tree_root_level(root_backup,
1739 btrfs_header_level(info->tree_root->node));
1740
1741 btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1742 btrfs_set_backup_chunk_root_gen(root_backup,
1743 btrfs_header_generation(info->chunk_root->node));
1744 btrfs_set_backup_chunk_root_level(root_backup,
1745 btrfs_header_level(info->chunk_root->node));
1746
1747 btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1748 btrfs_set_backup_extent_root_gen(root_backup,
1749 btrfs_header_generation(info->extent_root->node));
1750 btrfs_set_backup_extent_root_level(root_backup,
1751 btrfs_header_level(info->extent_root->node));
1752
1753 /*
1754 * we might commit during log recovery, which happens before we set
1755 * the fs_root. Make sure it is valid before we fill it in.
1756 */
1757 if (info->fs_root && info->fs_root->node) {
1758 btrfs_set_backup_fs_root(root_backup,
1759 info->fs_root->node->start);
1760 btrfs_set_backup_fs_root_gen(root_backup,
1761 btrfs_header_generation(info->fs_root->node));
1762 btrfs_set_backup_fs_root_level(root_backup,
1763 btrfs_header_level(info->fs_root->node));
1764 }
1765
1766 btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1767 btrfs_set_backup_dev_root_gen(root_backup,
1768 btrfs_header_generation(info->dev_root->node));
1769 btrfs_set_backup_dev_root_level(root_backup,
1770 btrfs_header_level(info->dev_root->node));
1771
1772 btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1773 btrfs_set_backup_csum_root_gen(root_backup,
1774 btrfs_header_generation(info->csum_root->node));
1775 btrfs_set_backup_csum_root_level(root_backup,
1776 btrfs_header_level(info->csum_root->node));
1777
1778 btrfs_set_backup_total_bytes(root_backup,
1779 btrfs_super_total_bytes(info->super_copy));
1780 btrfs_set_backup_bytes_used(root_backup,
1781 btrfs_super_bytes_used(info->super_copy));
1782 btrfs_set_backup_num_devices(root_backup,
1783 btrfs_super_num_devices(info->super_copy));
1784
1785 /*
1786 * if we don't copy this out to the super_copy, it won't get remembered
1787 * for the next commit
1788 */
1789 memcpy(&info->super_copy->super_roots,
1790 &info->super_for_commit->super_roots,
1791 sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1792 }
1793
1794 /*
1795 * this copies info out of the root backup array and back into
1796 * the in-memory super block. It is meant to help iterate through
1797 * the array, so you send it the number of backups you've already
1798 * tried and the last backup index you used.
1799 *
1800 * this returns -1 when it has tried all the backups
1801 */
1802 static noinline int next_root_backup(struct btrfs_fs_info *info,
1803 struct btrfs_super_block *super,
1804 int *num_backups_tried, int *backup_index)
1805 {
1806 struct btrfs_root_backup *root_backup;
1807 int newest = *backup_index;
1808
1809 if (*num_backups_tried == 0) {
1810 u64 gen = btrfs_super_generation(super);
1811
1812 newest = find_newest_super_backup(info, gen);
1813 if (newest == -1)
1814 return -1;
1815
1816 *backup_index = newest;
1817 *num_backups_tried = 1;
1818 } else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1819 /* we've tried all the backups, all done */
1820 return -1;
1821 } else {
1822 /* jump to the next oldest backup */
1823 newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1824 BTRFS_NUM_BACKUP_ROOTS;
1825 *backup_index = newest;
1826 *num_backups_tried += 1;
1827 }
1828 root_backup = super->super_roots + newest;
1829
1830 btrfs_set_super_generation(super,
1831 btrfs_backup_tree_root_gen(root_backup));
1832 btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1833 btrfs_set_super_root_level(super,
1834 btrfs_backup_tree_root_level(root_backup));
1835 btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1836
1837 /*
1838 * fixme: the total bytes and num_devices need to match or we should
1839 * need a fsck
1840 */
1841 btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1842 btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1843 return 0;
1844 }
1845
1846 /* helper to cleanup tree roots */
1847 static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
1848 {
1849 free_extent_buffer(info->tree_root->node);
1850 free_extent_buffer(info->tree_root->commit_root);
1851 free_extent_buffer(info->dev_root->node);
1852 free_extent_buffer(info->dev_root->commit_root);
1853 free_extent_buffer(info->extent_root->node);
1854 free_extent_buffer(info->extent_root->commit_root);
1855 free_extent_buffer(info->csum_root->node);
1856 free_extent_buffer(info->csum_root->commit_root);
1857
1858 info->tree_root->node = NULL;
1859 info->tree_root->commit_root = NULL;
1860 info->dev_root->node = NULL;
1861 info->dev_root->commit_root = NULL;
1862 info->extent_root->node = NULL;
1863 info->extent_root->commit_root = NULL;
1864 info->csum_root->node = NULL;
1865 info->csum_root->commit_root = NULL;
1866
1867 if (chunk_root) {
1868 free_extent_buffer(info->chunk_root->node);
1869 free_extent_buffer(info->chunk_root->commit_root);
1870 info->chunk_root->node = NULL;
1871 info->chunk_root->commit_root = NULL;
1872 }
1873 }
1874
1875
1876 struct btrfs_root *open_ctree(struct super_block *sb,
1877 struct btrfs_fs_devices *fs_devices,
1878 char *options)
1879 {
1880 u32 sectorsize;
1881 u32 nodesize;
1882 u32 leafsize;
1883 u32 blocksize;
1884 u32 stripesize;
1885 u64 generation;
1886 u64 features;
1887 struct btrfs_key location;
1888 struct buffer_head *bh;
1889 struct btrfs_super_block *disk_super;
1890 struct btrfs_root *tree_root = btrfs_sb(sb);
1891 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1892 struct btrfs_root *extent_root;
1893 struct btrfs_root *csum_root;
1894 struct btrfs_root *chunk_root;
1895 struct btrfs_root *dev_root;
1896 struct btrfs_root *log_tree_root;
1897 int ret;
1898 int err = -EINVAL;
1899 int num_backups_tried = 0;
1900 int backup_index = 0;
1901
1902 extent_root = fs_info->extent_root =
1903 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1904 csum_root = fs_info->csum_root =
1905 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1906 chunk_root = fs_info->chunk_root =
1907 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1908 dev_root = fs_info->dev_root =
1909 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1910
1911 if (!extent_root || !csum_root || !chunk_root || !dev_root) {
1912 err = -ENOMEM;
1913 goto fail;
1914 }
1915
1916 ret = init_srcu_struct(&fs_info->subvol_srcu);
1917 if (ret) {
1918 err = ret;
1919 goto fail;
1920 }
1921
1922 ret = setup_bdi(fs_info, &fs_info->bdi);
1923 if (ret) {
1924 err = ret;
1925 goto fail_srcu;
1926 }
1927
1928 fs_info->btree_inode = new_inode(sb);
1929 if (!fs_info->btree_inode) {
1930 err = -ENOMEM;
1931 goto fail_bdi;
1932 }
1933
1934 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
1935
1936 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
1937 INIT_LIST_HEAD(&fs_info->trans_list);
1938 INIT_LIST_HEAD(&fs_info->dead_roots);
1939 INIT_LIST_HEAD(&fs_info->delayed_iputs);
1940 INIT_LIST_HEAD(&fs_info->hashers);
1941 INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1942 INIT_LIST_HEAD(&fs_info->ordered_operations);
1943 INIT_LIST_HEAD(&fs_info->caching_block_groups);
1944 spin_lock_init(&fs_info->delalloc_lock);
1945 spin_lock_init(&fs_info->trans_lock);
1946 spin_lock_init(&fs_info->ref_cache_lock);
1947 spin_lock_init(&fs_info->fs_roots_radix_lock);
1948 spin_lock_init(&fs_info->delayed_iput_lock);
1949 spin_lock_init(&fs_info->defrag_inodes_lock);
1950 spin_lock_init(&fs_info->free_chunk_lock);
1951 mutex_init(&fs_info->reloc_mutex);
1952
1953 init_completion(&fs_info->kobj_unregister);
1954 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1955 INIT_LIST_HEAD(&fs_info->space_info);
1956 btrfs_mapping_init(&fs_info->mapping_tree);
1957 btrfs_init_block_rsv(&fs_info->global_block_rsv);
1958 btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
1959 btrfs_init_block_rsv(&fs_info->trans_block_rsv);
1960 btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
1961 btrfs_init_block_rsv(&fs_info->empty_block_rsv);
1962 btrfs_init_block_rsv(&fs_info->delayed_block_rsv);
1963 atomic_set(&fs_info->nr_async_submits, 0);
1964 atomic_set(&fs_info->async_delalloc_pages, 0);
1965 atomic_set(&fs_info->async_submit_draining, 0);
1966 atomic_set(&fs_info->nr_async_bios, 0);
1967 atomic_set(&fs_info->defrag_running, 0);
1968 fs_info->sb = sb;
1969 fs_info->max_inline = 8192 * 1024;
1970 fs_info->metadata_ratio = 0;
1971 fs_info->defrag_inodes = RB_ROOT;
1972 fs_info->trans_no_join = 0;
1973 fs_info->free_chunk_space = 0;
1974
1975 /* readahead state */
1976 INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
1977 spin_lock_init(&fs_info->reada_lock);
1978
1979 fs_info->thread_pool_size = min_t(unsigned long,
1980 num_online_cpus() + 2, 8);
1981
1982 INIT_LIST_HEAD(&fs_info->ordered_extents);
1983 spin_lock_init(&fs_info->ordered_extent_lock);
1984 fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
1985 GFP_NOFS);
1986 if (!fs_info->delayed_root) {
1987 err = -ENOMEM;
1988 goto fail_iput;
1989 }
1990 btrfs_init_delayed_root(fs_info->delayed_root);
1991
1992 mutex_init(&fs_info->scrub_lock);
1993 atomic_set(&fs_info->scrubs_running, 0);
1994 atomic_set(&fs_info->scrub_pause_req, 0);
1995 atomic_set(&fs_info->scrubs_paused, 0);
1996 atomic_set(&fs_info->scrub_cancel_req, 0);
1997 init_waitqueue_head(&fs_info->scrub_pause_wait);
1998 init_rwsem(&fs_info->scrub_super_lock);
1999 fs_info->scrub_workers_refcnt = 0;
2000
2001 sb->s_blocksize = 4096;
2002 sb->s_blocksize_bits = blksize_bits(4096);
2003 sb->s_bdi = &fs_info->bdi;
2004
2005 fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2006 set_nlink(fs_info->btree_inode, 1);
2007 /*
2008 * we set the i_size on the btree inode to the max possible int.
2009 * the real end of the address space is determined by all of
2010 * the devices in the system
2011 */
2012 fs_info->btree_inode->i_size = OFFSET_MAX;
2013 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
2014 fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
2015
2016 RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2017 extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2018 fs_info->btree_inode->i_mapping);
2019 extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2020
2021 BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2022
2023 BTRFS_I(fs_info->btree_inode)->root = tree_root;
2024 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2025 sizeof(struct btrfs_key));
2026 BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
2027 insert_inode_hash(fs_info->btree_inode);
2028
2029 spin_lock_init(&fs_info->block_group_cache_lock);
2030 fs_info->block_group_cache_tree = RB_ROOT;
2031
2032 extent_io_tree_init(&fs_info->freed_extents[0],
2033 fs_info->btree_inode->i_mapping);
2034 extent_io_tree_init(&fs_info->freed_extents[1],
2035 fs_info->btree_inode->i_mapping);
2036 fs_info->pinned_extents = &fs_info->freed_extents[0];
2037 fs_info->do_barriers = 1;
2038
2039
2040 mutex_init(&fs_info->ordered_operations_mutex);
2041 mutex_init(&fs_info->tree_log_mutex);
2042 mutex_init(&fs_info->chunk_mutex);
2043 mutex_init(&fs_info->transaction_kthread_mutex);
2044 mutex_init(&fs_info->cleaner_mutex);
2045 mutex_init(&fs_info->volume_mutex);
2046 init_rwsem(&fs_info->extent_commit_sem);
2047 init_rwsem(&fs_info->cleanup_work_sem);
2048 init_rwsem(&fs_info->subvol_sem);
2049
2050 btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2051 btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2052
2053 init_waitqueue_head(&fs_info->transaction_throttle);
2054 init_waitqueue_head(&fs_info->transaction_wait);
2055 init_waitqueue_head(&fs_info->transaction_blocked_wait);
2056 init_waitqueue_head(&fs_info->async_submit_wait);
2057
2058 __setup_root(4096, 4096, 4096, 4096, tree_root,
2059 fs_info, BTRFS_ROOT_TREE_OBJECTID);
2060
2061 bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2062 if (!bh) {
2063 err = -EINVAL;
2064 goto fail_alloc;
2065 }
2066
2067 memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2068 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2069 sizeof(*fs_info->super_for_commit));
2070 brelse(bh);
2071
2072 memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2073
2074 disk_super = fs_info->super_copy;
2075 if (!btrfs_super_root(disk_super))
2076 goto fail_alloc;
2077
2078 /* check FS state, whether FS is broken. */
2079 fs_info->fs_state |= btrfs_super_flags(disk_super);
2080
2081 btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2082
2083 /*
2084 * run through our array of backup supers and setup
2085 * our ring pointer to the oldest one
2086 */
2087 generation = btrfs_super_generation(disk_super);
2088 find_oldest_super_backup(fs_info, generation);
2089
2090 /*
2091 * In the long term, we'll store the compression type in the super
2092 * block, and it'll be used for per file compression control.
2093 */
2094 fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2095
2096 ret = btrfs_parse_options(tree_root, options);
2097 if (ret) {
2098 err = ret;
2099 goto fail_alloc;
2100 }
2101
2102 features = btrfs_super_incompat_flags(disk_super) &
2103 ~BTRFS_FEATURE_INCOMPAT_SUPP;
2104 if (features) {
2105 printk(KERN_ERR "BTRFS: couldn't mount because of "
2106 "unsupported optional features (%Lx).\n",
2107 (unsigned long long)features);
2108 err = -EINVAL;
2109 goto fail_alloc;
2110 }
2111
2112 features = btrfs_super_incompat_flags(disk_super);
2113 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2114 if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
2115 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2116 btrfs_set_super_incompat_flags(disk_super, features);
2117
2118 features = btrfs_super_compat_ro_flags(disk_super) &
2119 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
2120 if (!(sb->s_flags & MS_RDONLY) && features) {
2121 printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2122 "unsupported option features (%Lx).\n",
2123 (unsigned long long)features);
2124 err = -EINVAL;
2125 goto fail_alloc;
2126 }
2127
2128 btrfs_init_workers(&fs_info->generic_worker,
2129 "genwork", 1, NULL);
2130
2131 btrfs_init_workers(&fs_info->workers, "worker",
2132 fs_info->thread_pool_size,
2133 &fs_info->generic_worker);
2134
2135 btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
2136 fs_info->thread_pool_size,
2137 &fs_info->generic_worker);
2138
2139 btrfs_init_workers(&fs_info->submit_workers, "submit",
2140 min_t(u64, fs_devices->num_devices,
2141 fs_info->thread_pool_size),
2142 &fs_info->generic_worker);
2143
2144 btrfs_init_workers(&fs_info->caching_workers, "cache",
2145 2, &fs_info->generic_worker);
2146
2147 /* a higher idle thresh on the submit workers makes it much more
2148 * likely that bios will be send down in a sane order to the
2149 * devices
2150 */
2151 fs_info->submit_workers.idle_thresh = 64;
2152
2153 fs_info->workers.idle_thresh = 16;
2154 fs_info->workers.ordered = 1;
2155
2156 fs_info->delalloc_workers.idle_thresh = 2;
2157 fs_info->delalloc_workers.ordered = 1;
2158
2159 btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
2160 &fs_info->generic_worker);
2161 btrfs_init_workers(&fs_info->endio_workers, "endio",
2162 fs_info->thread_pool_size,
2163 &fs_info->generic_worker);
2164 btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
2165 fs_info->thread_pool_size,
2166 &fs_info->generic_worker);
2167 btrfs_init_workers(&fs_info->endio_meta_write_workers,
2168 "endio-meta-write", fs_info->thread_pool_size,
2169 &fs_info->generic_worker);
2170 btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
2171 fs_info->thread_pool_size,
2172 &fs_info->generic_worker);
2173 btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
2174 1, &fs_info->generic_worker);
2175 btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
2176 fs_info->thread_pool_size,
2177 &fs_info->generic_worker);
2178 btrfs_init_workers(&fs_info->readahead_workers, "readahead",
2179 fs_info->thread_pool_size,
2180 &fs_info->generic_worker);
2181
2182 /*
2183 * endios are largely parallel and should have a very
2184 * low idle thresh
2185 */
2186 fs_info->endio_workers.idle_thresh = 4;
2187 fs_info->endio_meta_workers.idle_thresh = 4;
2188
2189 fs_info->endio_write_workers.idle_thresh = 2;
2190 fs_info->endio_meta_write_workers.idle_thresh = 2;
2191 fs_info->readahead_workers.idle_thresh = 2;
2192
2193 /*
2194 * btrfs_start_workers can really only fail because of ENOMEM so just
2195 * return -ENOMEM if any of these fail.
2196 */
2197 ret = btrfs_start_workers(&fs_info->workers);
2198 ret |= btrfs_start_workers(&fs_info->generic_worker);
2199 ret |= btrfs_start_workers(&fs_info->submit_workers);
2200 ret |= btrfs_start_workers(&fs_info->delalloc_workers);
2201 ret |= btrfs_start_workers(&fs_info->fixup_workers);
2202 ret |= btrfs_start_workers(&fs_info->endio_workers);
2203 ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
2204 ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
2205 ret |= btrfs_start_workers(&fs_info->endio_write_workers);
2206 ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
2207 ret |= btrfs_start_workers(&fs_info->delayed_workers);
2208 ret |= btrfs_start_workers(&fs_info->caching_workers);
2209 ret |= btrfs_start_workers(&fs_info->readahead_workers);
2210 if (ret) {
2211 ret = -ENOMEM;
2212 goto fail_sb_buffer;
2213 }
2214
2215 fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2216 fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2217 4 * 1024 * 1024 / PAGE_CACHE_SIZE);
2218
2219 nodesize = btrfs_super_nodesize(disk_super);
2220 leafsize = btrfs_super_leafsize(disk_super);
2221 sectorsize = btrfs_super_sectorsize(disk_super);
2222 stripesize = btrfs_super_stripesize(disk_super);
2223 tree_root->nodesize = nodesize;
2224 tree_root->leafsize = leafsize;
2225 tree_root->sectorsize = sectorsize;
2226 tree_root->stripesize = stripesize;
2227
2228 sb->s_blocksize = sectorsize;
2229 sb->s_blocksize_bits = blksize_bits(sectorsize);
2230
2231 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
2232 sizeof(disk_super->magic))) {
2233 printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
2234 goto fail_sb_buffer;
2235 }
2236
2237 mutex_lock(&fs_info->chunk_mutex);
2238 ret = btrfs_read_sys_array(tree_root);
2239 mutex_unlock(&fs_info->chunk_mutex);
2240 if (ret) {
2241 printk(KERN_WARNING "btrfs: failed to read the system "
2242 "array on %s\n", sb->s_id);
2243 goto fail_sb_buffer;
2244 }
2245
2246 blocksize = btrfs_level_size(tree_root,
2247 btrfs_super_chunk_root_level(disk_super));
2248 generation = btrfs_super_chunk_root_generation(disk_super);
2249
2250 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2251 chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2252
2253 chunk_root->node = read_tree_block(chunk_root,
2254 btrfs_super_chunk_root(disk_super),
2255 blocksize, generation);
2256 BUG_ON(!chunk_root->node);
2257 if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
2258 printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
2259 sb->s_id);
2260 goto fail_tree_roots;
2261 }
2262 btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2263 chunk_root->commit_root = btrfs_root_node(chunk_root);
2264
2265 read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2266 (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
2267 BTRFS_UUID_SIZE);
2268
2269 mutex_lock(&fs_info->chunk_mutex);
2270 ret = btrfs_read_chunk_tree(chunk_root);
2271 mutex_unlock(&fs_info->chunk_mutex);
2272 if (ret) {
2273 printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
2274 sb->s_id);
2275 goto fail_tree_roots;
2276 }
2277
2278 btrfs_close_extra_devices(fs_devices);
2279
2280 retry_root_backup:
2281 blocksize = btrfs_level_size(tree_root,
2282 btrfs_super_root_level(disk_super));
2283 generation = btrfs_super_generation(disk_super);
2284
2285 tree_root->node = read_tree_block(tree_root,
2286 btrfs_super_root(disk_super),
2287 blocksize, generation);
2288 if (!tree_root->node ||
2289 !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
2290 printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
2291 sb->s_id);
2292
2293 goto recovery_tree_root;
2294 }
2295
2296 btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2297 tree_root->commit_root = btrfs_root_node(tree_root);
2298
2299 ret = find_and_setup_root(tree_root, fs_info,
2300 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
2301 if (ret)
2302 goto recovery_tree_root;
2303 extent_root->track_dirty = 1;
2304
2305 ret = find_and_setup_root(tree_root, fs_info,
2306 BTRFS_DEV_TREE_OBJECTID, dev_root);
2307 if (ret)
2308 goto recovery_tree_root;
2309 dev_root->track_dirty = 1;
2310
2311 ret = find_and_setup_root(tree_root, fs_info,
2312 BTRFS_CSUM_TREE_OBJECTID, csum_root);
2313 if (ret)
2314 goto recovery_tree_root;
2315
2316 csum_root->track_dirty = 1;
2317
2318 fs_info->generation = generation;
2319 fs_info->last_trans_committed = generation;
2320 fs_info->data_alloc_profile = (u64)-1;
2321 fs_info->metadata_alloc_profile = (u64)-1;
2322 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
2323
2324 ret = btrfs_init_space_info(fs_info);
2325 if (ret) {
2326 printk(KERN_ERR "Failed to initial space info: %d\n", ret);
2327 goto fail_block_groups;
2328 }
2329
2330 ret = btrfs_read_block_groups(extent_root);
2331 if (ret) {
2332 printk(KERN_ERR "Failed to read block groups: %d\n", ret);
2333 goto fail_block_groups;
2334 }
2335
2336 fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2337 "btrfs-cleaner");
2338 if (IS_ERR(fs_info->cleaner_kthread))
2339 goto fail_block_groups;
2340
2341 fs_info->transaction_kthread = kthread_run(transaction_kthread,
2342 tree_root,
2343 "btrfs-transaction");
2344 if (IS_ERR(fs_info->transaction_kthread))
2345 goto fail_cleaner;
2346
2347 if (!btrfs_test_opt(tree_root, SSD) &&
2348 !btrfs_test_opt(tree_root, NOSSD) &&
2349 !fs_info->fs_devices->rotating) {
2350 printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
2351 "mode\n");
2352 btrfs_set_opt(fs_info->mount_opt, SSD);
2353 }
2354
2355 /* do not make disk changes in broken FS */
2356 if (btrfs_super_log_root(disk_super) != 0 &&
2357 !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
2358 u64 bytenr = btrfs_super_log_root(disk_super);
2359
2360 if (fs_devices->rw_devices == 0) {
2361 printk(KERN_WARNING "Btrfs log replay required "
2362 "on RO media\n");
2363 err = -EIO;
2364 goto fail_trans_kthread;
2365 }
2366 blocksize =
2367 btrfs_level_size(tree_root,
2368 btrfs_super_log_root_level(disk_super));
2369
2370 log_tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
2371 if (!log_tree_root) {
2372 err = -ENOMEM;
2373 goto fail_trans_kthread;
2374 }
2375
2376 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2377 log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2378
2379 log_tree_root->node = read_tree_block(tree_root, bytenr,
2380 blocksize,
2381 generation + 1);
2382 ret = btrfs_recover_log_trees(log_tree_root);
2383 BUG_ON(ret);
2384
2385 if (sb->s_flags & MS_RDONLY) {
2386 ret = btrfs_commit_super(tree_root);
2387 BUG_ON(ret);
2388 }
2389 }
2390
2391 ret = btrfs_find_orphan_roots(tree_root);
2392 BUG_ON(ret);
2393
2394 if (!(sb->s_flags & MS_RDONLY)) {
2395 ret = btrfs_cleanup_fs_roots(fs_info);
2396 BUG_ON(ret);
2397
2398 ret = btrfs_recover_relocation(tree_root);
2399 if (ret < 0) {
2400 printk(KERN_WARNING
2401 "btrfs: failed to recover relocation\n");
2402 err = -EINVAL;
2403 goto fail_trans_kthread;
2404 }
2405 }
2406
2407 location.objectid = BTRFS_FS_TREE_OBJECTID;
2408 location.type = BTRFS_ROOT_ITEM_KEY;
2409 location.offset = (u64)-1;
2410
2411 fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2412 if (!fs_info->fs_root)
2413 goto fail_trans_kthread;
2414 if (IS_ERR(fs_info->fs_root)) {
2415 err = PTR_ERR(fs_info->fs_root);
2416 goto fail_trans_kthread;
2417 }
2418
2419 if (!(sb->s_flags & MS_RDONLY)) {
2420 down_read(&fs_info->cleanup_work_sem);
2421 err = btrfs_orphan_cleanup(fs_info->fs_root);
2422 if (!err)
2423 err = btrfs_orphan_cleanup(fs_info->tree_root);
2424 up_read(&fs_info->cleanup_work_sem);
2425 if (err) {
2426 close_ctree(tree_root);
2427 return ERR_PTR(err);
2428 }
2429 }
2430
2431 return tree_root;
2432
2433 fail_trans_kthread:
2434 kthread_stop(fs_info->transaction_kthread);
2435 fail_cleaner:
2436 kthread_stop(fs_info->cleaner_kthread);
2437
2438 /*
2439 * make sure we're done with the btree inode before we stop our
2440 * kthreads
2441 */
2442 filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2443 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2444
2445 fail_block_groups:
2446 btrfs_free_block_groups(fs_info);
2447
2448 fail_tree_roots:
2449 free_root_pointers(fs_info, 1);
2450
2451 fail_sb_buffer:
2452 btrfs_stop_workers(&fs_info->generic_worker);
2453 btrfs_stop_workers(&fs_info->readahead_workers);
2454 btrfs_stop_workers(&fs_info->fixup_workers);
2455 btrfs_stop_workers(&fs_info->delalloc_workers);
2456 btrfs_stop_workers(&fs_info->workers);
2457 btrfs_stop_workers(&fs_info->endio_workers);
2458 btrfs_stop_workers(&fs_info->endio_meta_workers);
2459 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2460 btrfs_stop_workers(&fs_info->endio_write_workers);
2461 btrfs_stop_workers(&fs_info->endio_freespace_worker);
2462 btrfs_stop_workers(&fs_info->submit_workers);
2463 btrfs_stop_workers(&fs_info->delayed_workers);
2464 btrfs_stop_workers(&fs_info->caching_workers);
2465 fail_alloc:
2466 fail_iput:
2467 btrfs_mapping_tree_free(&fs_info->mapping_tree);
2468
2469 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2470 iput(fs_info->btree_inode);
2471 fail_bdi:
2472 bdi_destroy(&fs_info->bdi);
2473 fail_srcu:
2474 cleanup_srcu_struct(&fs_info->subvol_srcu);
2475 fail:
2476 btrfs_close_devices(fs_info->fs_devices);
2477 free_fs_info(fs_info);
2478 return ERR_PTR(err);
2479
2480 recovery_tree_root:
2481 if (!btrfs_test_opt(tree_root, RECOVERY))
2482 goto fail_tree_roots;
2483
2484 free_root_pointers(fs_info, 0);
2485
2486 /* don't use the log in recovery mode, it won't be valid */
2487 btrfs_set_super_log_root(disk_super, 0);
2488
2489 /* we can't trust the free space cache either */
2490 btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
2491
2492 ret = next_root_backup(fs_info, fs_info->super_copy,
2493 &num_backups_tried, &backup_index);
2494 if (ret == -1)
2495 goto fail_block_groups;
2496 goto retry_root_backup;
2497 }
2498
2499 static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
2500 {
2501 char b[BDEVNAME_SIZE];
2502
2503 if (uptodate) {
2504 set_buffer_uptodate(bh);
2505 } else {
2506 printk_ratelimited(KERN_WARNING "lost page write due to "
2507 "I/O error on %s\n",
2508 bdevname(bh->b_bdev, b));
2509 /* note, we dont' set_buffer_write_io_error because we have
2510 * our own ways of dealing with the IO errors
2511 */
2512 clear_buffer_uptodate(bh);
2513 }
2514 unlock_buffer(bh);
2515 put_bh(bh);
2516 }
2517
2518 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
2519 {
2520 struct buffer_head *bh;
2521 struct buffer_head *latest = NULL;
2522 struct btrfs_super_block *super;
2523 int i;
2524 u64 transid = 0;
2525 u64 bytenr;
2526
2527 /* we would like to check all the supers, but that would make
2528 * a btrfs mount succeed after a mkfs from a different FS.
2529 * So, we need to add a special mount option to scan for
2530 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2531 */
2532 for (i = 0; i < 1; i++) {
2533 bytenr = btrfs_sb_offset(i);
2534 if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2535 break;
2536 bh = __bread(bdev, bytenr / 4096, 4096);
2537 if (!bh)
2538 continue;
2539
2540 super = (struct btrfs_super_block *)bh->b_data;
2541 if (btrfs_super_bytenr(super) != bytenr ||
2542 strncmp((char *)(&super->magic), BTRFS_MAGIC,
2543 sizeof(super->magic))) {
2544 brelse(bh);
2545 continue;
2546 }
2547
2548 if (!latest || btrfs_super_generation(super) > transid) {
2549 brelse(latest);
2550 latest = bh;
2551 transid = btrfs_super_generation(super);
2552 } else {
2553 brelse(bh);
2554 }
2555 }
2556 return latest;
2557 }
2558
2559 /*
2560 * this should be called twice, once with wait == 0 and
2561 * once with wait == 1. When wait == 0 is done, all the buffer heads
2562 * we write are pinned.
2563 *
2564 * They are released when wait == 1 is done.
2565 * max_mirrors must be the same for both runs, and it indicates how
2566 * many supers on this one device should be written.
2567 *
2568 * max_mirrors == 0 means to write them all.
2569 */
2570 static int write_dev_supers(struct btrfs_device *device,
2571 struct btrfs_super_block *sb,
2572 int do_barriers, int wait, int max_mirrors)
2573 {
2574 struct buffer_head *bh;
2575 int i;
2576 int ret;
2577 int errors = 0;
2578 u32 crc;
2579 u64 bytenr;
2580
2581 if (max_mirrors == 0)
2582 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2583
2584 for (i = 0; i < max_mirrors; i++) {
2585 bytenr = btrfs_sb_offset(i);
2586 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
2587 break;
2588
2589 if (wait) {
2590 bh = __find_get_block(device->bdev, bytenr / 4096,
2591 BTRFS_SUPER_INFO_SIZE);
2592 BUG_ON(!bh);
2593 wait_on_buffer(bh);
2594 if (!buffer_uptodate(bh))
2595 errors++;
2596
2597 /* drop our reference */
2598 brelse(bh);
2599
2600 /* drop the reference from the wait == 0 run */
2601 brelse(bh);
2602 continue;
2603 } else {
2604 btrfs_set_super_bytenr(sb, bytenr);
2605
2606 crc = ~(u32)0;
2607 crc = btrfs_csum_data(NULL, (char *)sb +
2608 BTRFS_CSUM_SIZE, crc,
2609 BTRFS_SUPER_INFO_SIZE -
2610 BTRFS_CSUM_SIZE);
2611 btrfs_csum_final(crc, sb->csum);
2612
2613 /*
2614 * one reference for us, and we leave it for the
2615 * caller
2616 */
2617 bh = __getblk(device->bdev, bytenr / 4096,
2618 BTRFS_SUPER_INFO_SIZE);
2619 memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2620
2621 /* one reference for submit_bh */
2622 get_bh(bh);
2623
2624 set_buffer_uptodate(bh);
2625 lock_buffer(bh);
2626 bh->b_end_io = btrfs_end_buffer_write_sync;
2627 }
2628
2629 /*
2630 * we fua the first super. The others we allow
2631 * to go down lazy.
2632 */
2633 ret = submit_bh(WRITE_FUA, bh);
2634 if (ret)
2635 errors++;
2636 }
2637 return errors < i ? 0 : -1;
2638 }
2639
2640 /*
2641 * endio for the write_dev_flush, this will wake anyone waiting
2642 * for the barrier when it is done
2643 */
2644 static void btrfs_end_empty_barrier(struct bio *bio, int err)
2645 {
2646 if (err) {
2647 if (err == -EOPNOTSUPP)
2648 set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
2649 clear_bit(BIO_UPTODATE, &bio->bi_flags);
2650 }
2651 if (bio->bi_private)
2652 complete(bio->bi_private);
2653 bio_put(bio);
2654 }
2655
2656 /*
2657 * trigger flushes for one the devices. If you pass wait == 0, the flushes are
2658 * sent down. With wait == 1, it waits for the previous flush.
2659 *
2660 * any device where the flush fails with eopnotsupp are flagged as not-barrier
2661 * capable
2662 */
2663 static int write_dev_flush(struct btrfs_device *device, int wait)
2664 {
2665 struct bio *bio;
2666 int ret = 0;
2667
2668 if (device->nobarriers)
2669 return 0;
2670
2671 if (wait) {
2672 bio = device->flush_bio;
2673 if (!bio)
2674 return 0;
2675
2676 wait_for_completion(&device->flush_wait);
2677
2678 if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
2679 printk("btrfs: disabling barriers on dev %s\n",
2680 device->name);
2681 device->nobarriers = 1;
2682 }
2683 if (!bio_flagged(bio, BIO_UPTODATE)) {
2684 ret = -EIO;
2685 }
2686
2687 /* drop the reference from the wait == 0 run */
2688 bio_put(bio);
2689 device->flush_bio = NULL;
2690
2691 return ret;
2692 }
2693
2694 /*
2695 * one reference for us, and we leave it for the
2696 * caller
2697 */
2698 device->flush_bio = NULL;;
2699 bio = bio_alloc(GFP_NOFS, 0);
2700 if (!bio)
2701 return -ENOMEM;
2702
2703 bio->bi_end_io = btrfs_end_empty_barrier;
2704 bio->bi_bdev = device->bdev;
2705 init_completion(&device->flush_wait);
2706 bio->bi_private = &device->flush_wait;
2707 device->flush_bio = bio;
2708
2709 bio_get(bio);
2710 submit_bio(WRITE_FLUSH, bio);
2711
2712 return 0;
2713 }
2714
2715 /*
2716 * send an empty flush down to each device in parallel,
2717 * then wait for them
2718 */
2719 static int barrier_all_devices(struct btrfs_fs_info *info)
2720 {
2721 struct list_head *head;
2722 struct btrfs_device *dev;
2723 int errors = 0;
2724 int ret;
2725
2726 /* send down all the barriers */
2727 head = &info->fs_devices->devices;
2728 list_for_each_entry_rcu(dev, head, dev_list) {
2729 if (!dev->bdev) {
2730 errors++;
2731 continue;
2732 }
2733 if (!dev->in_fs_metadata || !dev->writeable)
2734 continue;
2735
2736 ret = write_dev_flush(dev, 0);
2737 if (ret)
2738 errors++;
2739 }
2740
2741 /* wait for all the barriers */
2742 list_for_each_entry_rcu(dev, head, dev_list) {
2743 if (!dev->bdev) {
2744 errors++;
2745 continue;
2746 }
2747 if (!dev->in_fs_metadata || !dev->writeable)
2748 continue;
2749
2750 ret = write_dev_flush(dev, 1);
2751 if (ret)
2752 errors++;
2753 }
2754 if (errors)
2755 return -EIO;
2756 return 0;
2757 }
2758
2759 int write_all_supers(struct btrfs_root *root, int max_mirrors)
2760 {
2761 struct list_head *head;
2762 struct btrfs_device *dev;
2763 struct btrfs_super_block *sb;
2764 struct btrfs_dev_item *dev_item;
2765 int ret;
2766 int do_barriers;
2767 int max_errors;
2768 int total_errors = 0;
2769 u64 flags;
2770
2771 max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
2772 do_barriers = !btrfs_test_opt(root, NOBARRIER);
2773 backup_super_roots(root->fs_info);
2774
2775 sb = root->fs_info->super_for_commit;
2776 dev_item = &sb->dev_item;
2777
2778 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2779 head = &root->fs_info->fs_devices->devices;
2780
2781 if (do_barriers)
2782 barrier_all_devices(root->fs_info);
2783
2784 list_for_each_entry_rcu(dev, head, dev_list) {
2785 if (!dev->bdev) {
2786 total_errors++;
2787 continue;
2788 }
2789 if (!dev->in_fs_metadata || !dev->writeable)
2790 continue;
2791
2792 btrfs_set_stack_device_generation(dev_item, 0);
2793 btrfs_set_stack_device_type(dev_item, dev->type);
2794 btrfs_set_stack_device_id(dev_item, dev->devid);
2795 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
2796 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
2797 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
2798 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
2799 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
2800 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
2801 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
2802
2803 flags = btrfs_super_flags(sb);
2804 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
2805
2806 ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
2807 if (ret)
2808 total_errors++;
2809 }
2810 if (total_errors > max_errors) {
2811 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2812 total_errors);
2813 BUG();
2814 }
2815
2816 total_errors = 0;
2817 list_for_each_entry_rcu(dev, head, dev_list) {
2818 if (!dev->bdev)
2819 continue;
2820 if (!dev->in_fs_metadata || !dev->writeable)
2821 continue;
2822
2823 ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
2824 if (ret)
2825 total_errors++;
2826 }
2827 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2828 if (total_errors > max_errors) {
2829 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2830 total_errors);
2831 BUG();
2832 }
2833 return 0;
2834 }
2835
2836 int write_ctree_super(struct btrfs_trans_handle *trans,
2837 struct btrfs_root *root, int max_mirrors)
2838 {
2839 int ret;
2840
2841 ret = write_all_supers(root, max_mirrors);
2842 return ret;
2843 }
2844
2845 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2846 {
2847 spin_lock(&fs_info->fs_roots_radix_lock);
2848 radix_tree_delete(&fs_info->fs_roots_radix,
2849 (unsigned long)root->root_key.objectid);
2850 spin_unlock(&fs_info->fs_roots_radix_lock);
2851
2852 if (btrfs_root_refs(&root->root_item) == 0)
2853 synchronize_srcu(&fs_info->subvol_srcu);
2854
2855 __btrfs_remove_free_space_cache(root->free_ino_pinned);
2856 __btrfs_remove_free_space_cache(root->free_ino_ctl);
2857 free_fs_root(root);
2858 return 0;
2859 }
2860
2861 static void free_fs_root(struct btrfs_root *root)
2862 {
2863 iput(root->cache_inode);
2864 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2865 if (root->anon_dev)
2866 free_anon_bdev(root->anon_dev);
2867 free_extent_buffer(root->node);
2868 free_extent_buffer(root->commit_root);
2869 kfree(root->free_ino_ctl);
2870 kfree(root->free_ino_pinned);
2871 kfree(root->name);
2872 kfree(root);
2873 }
2874
2875 static int del_fs_roots(struct btrfs_fs_info *fs_info)
2876 {
2877 int ret;
2878 struct btrfs_root *gang[8];
2879 int i;
2880
2881 while (!list_empty(&fs_info->dead_roots)) {
2882 gang[0] = list_entry(fs_info->dead_roots.next,
2883 struct btrfs_root, root_list);
2884 list_del(&gang[0]->root_list);
2885
2886 if (gang[0]->in_radix) {
2887 btrfs_free_fs_root(fs_info, gang[0]);
2888 } else {
2889 free_extent_buffer(gang[0]->node);
2890 free_extent_buffer(gang[0]->commit_root);
2891 kfree(gang[0]);
2892 }
2893 }
2894
2895 while (1) {
2896 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2897 (void **)gang, 0,
2898 ARRAY_SIZE(gang));
2899 if (!ret)
2900 break;
2901 for (i = 0; i < ret; i++)
2902 btrfs_free_fs_root(fs_info, gang[i]);
2903 }
2904 return 0;
2905 }
2906
2907 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2908 {
2909 u64 root_objectid = 0;
2910 struct btrfs_root *gang[8];
2911 int i;
2912 int ret;
2913
2914 while (1) {
2915 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2916 (void **)gang, root_objectid,
2917 ARRAY_SIZE(gang));
2918 if (!ret)
2919 break;
2920
2921 root_objectid = gang[ret - 1]->root_key.objectid + 1;
2922 for (i = 0; i < ret; i++) {
2923 int err;
2924
2925 root_objectid = gang[i]->root_key.objectid;
2926 err = btrfs_orphan_cleanup(gang[i]);
2927 if (err)
2928 return err;
2929 }
2930 root_objectid++;
2931 }
2932 return 0;
2933 }
2934
2935 int btrfs_commit_super(struct btrfs_root *root)
2936 {
2937 struct btrfs_trans_handle *trans;
2938 int ret;
2939
2940 mutex_lock(&root->fs_info->cleaner_mutex);
2941 btrfs_run_delayed_iputs(root);
2942 btrfs_clean_old_snapshots(root);
2943 mutex_unlock(&root->fs_info->cleaner_mutex);
2944
2945 /* wait until ongoing cleanup work done */
2946 down_write(&root->fs_info->cleanup_work_sem);
2947 up_write(&root->fs_info->cleanup_work_sem);
2948
2949 trans = btrfs_join_transaction(root);
2950 if (IS_ERR(trans))
2951 return PTR_ERR(trans);
2952 ret = btrfs_commit_transaction(trans, root);
2953 BUG_ON(ret);
2954 /* run commit again to drop the original snapshot */
2955 trans = btrfs_join_transaction(root);
2956 if (IS_ERR(trans))
2957 return PTR_ERR(trans);
2958 btrfs_commit_transaction(trans, root);
2959 ret = btrfs_write_and_wait_transaction(NULL, root);
2960 BUG_ON(ret);
2961
2962 ret = write_ctree_super(NULL, root, 0);
2963 return ret;
2964 }
2965
2966 int close_ctree(struct btrfs_root *root)
2967 {
2968 struct btrfs_fs_info *fs_info = root->fs_info;
2969 int ret;
2970
2971 fs_info->closing = 1;
2972 smp_mb();
2973
2974 btrfs_scrub_cancel(root);
2975
2976 /* wait for any defraggers to finish */
2977 wait_event(fs_info->transaction_wait,
2978 (atomic_read(&fs_info->defrag_running) == 0));
2979
2980 /* clear out the rbtree of defraggable inodes */
2981 btrfs_run_defrag_inodes(root->fs_info);
2982
2983 /*
2984 * Here come 2 situations when btrfs is broken to flip readonly:
2985 *
2986 * 1. when btrfs flips readonly somewhere else before
2987 * btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
2988 * and btrfs will skip to write sb directly to keep
2989 * ERROR state on disk.
2990 *
2991 * 2. when btrfs flips readonly just in btrfs_commit_super,
2992 * and in such case, btrfs cannot write sb via btrfs_commit_super,
2993 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
2994 * btrfs will cleanup all FS resources first and write sb then.
2995 */
2996 if (!(fs_info->sb->s_flags & MS_RDONLY)) {
2997 ret = btrfs_commit_super(root);
2998 if (ret)
2999 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3000 }
3001
3002 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
3003 ret = btrfs_error_commit_super(root);
3004 if (ret)
3005 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3006 }
3007
3008 btrfs_put_block_group_cache(fs_info);
3009
3010 kthread_stop(root->fs_info->transaction_kthread);
3011 kthread_stop(root->fs_info->cleaner_kthread);
3012
3013 fs_info->closing = 2;
3014 smp_mb();
3015
3016 if (fs_info->delalloc_bytes) {
3017 printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
3018 (unsigned long long)fs_info->delalloc_bytes);
3019 }
3020 if (fs_info->total_ref_cache_size) {
3021 printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
3022 (unsigned long long)fs_info->total_ref_cache_size);
3023 }
3024
3025 free_extent_buffer(fs_info->extent_root->node);
3026 free_extent_buffer(fs_info->extent_root->commit_root);
3027 free_extent_buffer(fs_info->tree_root->node);
3028 free_extent_buffer(fs_info->tree_root->commit_root);
3029 free_extent_buffer(root->fs_info->chunk_root->node);
3030 free_extent_buffer(root->fs_info->chunk_root->commit_root);
3031 free_extent_buffer(root->fs_info->dev_root->node);
3032 free_extent_buffer(root->fs_info->dev_root->commit_root);
3033 free_extent_buffer(root->fs_info->csum_root->node);
3034 free_extent_buffer(root->fs_info->csum_root->commit_root);
3035
3036 btrfs_free_block_groups(root->fs_info);
3037
3038 del_fs_roots(fs_info);
3039
3040 iput(fs_info->btree_inode);
3041
3042 btrfs_stop_workers(&fs_info->generic_worker);
3043 btrfs_stop_workers(&fs_info->fixup_workers);
3044 btrfs_stop_workers(&fs_info->delalloc_workers);
3045 btrfs_stop_workers(&fs_info->workers);
3046 btrfs_stop_workers(&fs_info->endio_workers);
3047 btrfs_stop_workers(&fs_info->endio_meta_workers);
3048 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
3049 btrfs_stop_workers(&fs_info->endio_write_workers);
3050 btrfs_stop_workers(&fs_info->endio_freespace_worker);
3051 btrfs_stop_workers(&fs_info->submit_workers);
3052 btrfs_stop_workers(&fs_info->delayed_workers);
3053 btrfs_stop_workers(&fs_info->caching_workers);
3054 btrfs_stop_workers(&fs_info->readahead_workers);
3055
3056 btrfs_close_devices(fs_info->fs_devices);
3057 btrfs_mapping_tree_free(&fs_info->mapping_tree);
3058
3059 bdi_destroy(&fs_info->bdi);
3060 cleanup_srcu_struct(&fs_info->subvol_srcu);
3061
3062 free_fs_info(fs_info);
3063
3064 return 0;
3065 }
3066
3067 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
3068 {
3069 int ret;
3070 struct inode *btree_inode = buf->first_page->mapping->host;
3071
3072 ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
3073 NULL);
3074 if (!ret)
3075 return ret;
3076
3077 ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3078 parent_transid);
3079 return !ret;
3080 }
3081
3082 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
3083 {
3084 struct inode *btree_inode = buf->first_page->mapping->host;
3085 return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
3086 buf);
3087 }
3088
3089 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3090 {
3091 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
3092 u64 transid = btrfs_header_generation(buf);
3093 struct inode *btree_inode = root->fs_info->btree_inode;
3094 int was_dirty;
3095
3096 btrfs_assert_tree_locked(buf);
3097 if (transid != root->fs_info->generation) {
3098 printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
3099 "found %llu running %llu\n",
3100 (unsigned long long)buf->start,
3101 (unsigned long long)transid,
3102 (unsigned long long)root->fs_info->generation);
3103 WARN_ON(1);
3104 }
3105 was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
3106 buf);
3107 if (!was_dirty) {
3108 spin_lock(&root->fs_info->delalloc_lock);
3109 root->fs_info->dirty_metadata_bytes += buf->len;
3110 spin_unlock(&root->fs_info->delalloc_lock);
3111 }
3112 }
3113
3114 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
3115 {
3116 /*
3117 * looks as though older kernels can get into trouble with
3118 * this code, they end up stuck in balance_dirty_pages forever
3119 */
3120 u64 num_dirty;
3121 unsigned long thresh = 32 * 1024 * 1024;
3122
3123 if (current->flags & PF_MEMALLOC)
3124 return;
3125
3126 btrfs_balance_delayed_items(root);
3127
3128 num_dirty = root->fs_info->dirty_metadata_bytes;
3129
3130 if (num_dirty > thresh) {
3131 balance_dirty_pages_ratelimited_nr(
3132 root->fs_info->btree_inode->i_mapping, 1);
3133 }
3134 return;
3135 }
3136
3137 void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
3138 {
3139 /*
3140 * looks as though older kernels can get into trouble with
3141 * this code, they end up stuck in balance_dirty_pages forever
3142 */
3143 u64 num_dirty;
3144 unsigned long thresh = 32 * 1024 * 1024;
3145
3146 if (current->flags & PF_MEMALLOC)
3147 return;
3148
3149 num_dirty = root->fs_info->dirty_metadata_bytes;
3150
3151 if (num_dirty > thresh) {
3152 balance_dirty_pages_ratelimited_nr(
3153 root->fs_info->btree_inode->i_mapping, 1);
3154 }
3155 return;
3156 }
3157
3158 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
3159 {
3160 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
3161 int ret;
3162 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
3163 if (ret == 0)
3164 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
3165 return ret;
3166 }
3167
3168 static int btree_lock_page_hook(struct page *page, void *data,
3169 void (*flush_fn)(void *))
3170 {
3171 struct inode *inode = page->mapping->host;
3172 struct btrfs_root *root = BTRFS_I(inode)->root;
3173 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3174 struct extent_buffer *eb;
3175 unsigned long len;
3176 u64 bytenr = page_offset(page);
3177
3178 if (page->private == EXTENT_PAGE_PRIVATE)
3179 goto out;
3180
3181 len = page->private >> 2;
3182 eb = find_extent_buffer(io_tree, bytenr, len);
3183 if (!eb)
3184 goto out;
3185
3186 if (!btrfs_try_tree_write_lock(eb)) {
3187 flush_fn(data);
3188 btrfs_tree_lock(eb);
3189 }
3190 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
3191
3192 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
3193 spin_lock(&root->fs_info->delalloc_lock);
3194 if (root->fs_info->dirty_metadata_bytes >= eb->len)
3195 root->fs_info->dirty_metadata_bytes -= eb->len;
3196 else
3197 WARN_ON(1);
3198 spin_unlock(&root->fs_info->delalloc_lock);
3199 }
3200
3201 btrfs_tree_unlock(eb);
3202 free_extent_buffer(eb);
3203 out:
3204 if (!trylock_page(page)) {
3205 flush_fn(data);
3206 lock_page(page);
3207 }
3208 return 0;
3209 }
3210
3211 static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
3212 int read_only)
3213 {
3214 if (read_only)
3215 return;
3216
3217 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
3218 printk(KERN_WARNING "warning: mount fs with errors, "
3219 "running btrfsck is recommended\n");
3220 }
3221
3222 int btrfs_error_commit_super(struct btrfs_root *root)
3223 {
3224 int ret;
3225
3226 mutex_lock(&root->fs_info->cleaner_mutex);
3227 btrfs_run_delayed_iputs(root);
3228 mutex_unlock(&root->fs_info->cleaner_mutex);
3229
3230 down_write(&root->fs_info->cleanup_work_sem);
3231 up_write(&root->fs_info->cleanup_work_sem);
3232
3233 /* cleanup FS via transaction */
3234 btrfs_cleanup_transaction(root);
3235
3236 ret = write_ctree_super(NULL, root, 0);
3237
3238 return ret;
3239 }
3240
3241 static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
3242 {
3243 struct btrfs_inode *btrfs_inode;
3244 struct list_head splice;
3245
3246 INIT_LIST_HEAD(&splice);
3247
3248 mutex_lock(&root->fs_info->ordered_operations_mutex);
3249 spin_lock(&root->fs_info->ordered_extent_lock);
3250
3251 list_splice_init(&root->fs_info->ordered_operations, &splice);
3252 while (!list_empty(&splice)) {
3253 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3254 ordered_operations);
3255
3256 list_del_init(&btrfs_inode->ordered_operations);
3257
3258 btrfs_invalidate_inodes(btrfs_inode->root);
3259 }
3260
3261 spin_unlock(&root->fs_info->ordered_extent_lock);
3262 mutex_unlock(&root->fs_info->ordered_operations_mutex);
3263
3264 return 0;
3265 }
3266
3267 static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
3268 {
3269 struct list_head splice;
3270 struct btrfs_ordered_extent *ordered;
3271 struct inode *inode;
3272
3273 INIT_LIST_HEAD(&splice);
3274
3275 spin_lock(&root->fs_info->ordered_extent_lock);
3276
3277 list_splice_init(&root->fs_info->ordered_extents, &splice);
3278 while (!list_empty(&splice)) {
3279 ordered = list_entry(splice.next, struct btrfs_ordered_extent,
3280 root_extent_list);
3281
3282 list_del_init(&ordered->root_extent_list);
3283 atomic_inc(&ordered->refs);
3284
3285 /* the inode may be getting freed (in sys_unlink path). */
3286 inode = igrab(ordered->inode);
3287
3288 spin_unlock(&root->fs_info->ordered_extent_lock);
3289 if (inode)
3290 iput(inode);
3291
3292 atomic_set(&ordered->refs, 1);
3293 btrfs_put_ordered_extent(ordered);
3294
3295 spin_lock(&root->fs_info->ordered_extent_lock);
3296 }
3297
3298 spin_unlock(&root->fs_info->ordered_extent_lock);
3299
3300 return 0;
3301 }
3302
3303 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
3304 struct btrfs_root *root)
3305 {
3306 struct rb_node *node;
3307 struct btrfs_delayed_ref_root *delayed_refs;
3308 struct btrfs_delayed_ref_node *ref;
3309 int ret = 0;
3310
3311 delayed_refs = &trans->delayed_refs;
3312
3313 spin_lock(&delayed_refs->lock);
3314 if (delayed_refs->num_entries == 0) {
3315 spin_unlock(&delayed_refs->lock);
3316 printk(KERN_INFO "delayed_refs has NO entry\n");
3317 return ret;
3318 }
3319
3320 node = rb_first(&delayed_refs->root);
3321 while (node) {
3322 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3323 node = rb_next(node);
3324
3325 ref->in_tree = 0;
3326 rb_erase(&ref->rb_node, &delayed_refs->root);
3327 delayed_refs->num_entries--;
3328
3329 atomic_set(&ref->refs, 1);
3330 if (btrfs_delayed_ref_is_head(ref)) {
3331 struct btrfs_delayed_ref_head *head;
3332
3333 head = btrfs_delayed_node_to_head(ref);
3334 mutex_lock(&head->mutex);
3335 kfree(head->extent_op);
3336 delayed_refs->num_heads--;
3337 if (list_empty(&head->cluster))
3338 delayed_refs->num_heads_ready--;
3339 list_del_init(&head->cluster);
3340 mutex_unlock(&head->mutex);
3341 }
3342
3343 spin_unlock(&delayed_refs->lock);
3344 btrfs_put_delayed_ref(ref);
3345
3346 cond_resched();
3347 spin_lock(&delayed_refs->lock);
3348 }
3349
3350 spin_unlock(&delayed_refs->lock);
3351
3352 return ret;
3353 }
3354
3355 static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
3356 {
3357 struct btrfs_pending_snapshot *snapshot;
3358 struct list_head splice;
3359
3360 INIT_LIST_HEAD(&splice);
3361
3362 list_splice_init(&t->pending_snapshots, &splice);
3363
3364 while (!list_empty(&splice)) {
3365 snapshot = list_entry(splice.next,
3366 struct btrfs_pending_snapshot,
3367 list);
3368
3369 list_del_init(&snapshot->list);
3370
3371 kfree(snapshot);
3372 }
3373
3374 return 0;
3375 }
3376
3377 static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
3378 {
3379 struct btrfs_inode *btrfs_inode;
3380 struct list_head splice;
3381
3382 INIT_LIST_HEAD(&splice);
3383
3384 spin_lock(&root->fs_info->delalloc_lock);
3385 list_splice_init(&root->fs_info->delalloc_inodes, &splice);
3386
3387 while (!list_empty(&splice)) {
3388 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3389 delalloc_inodes);
3390
3391 list_del_init(&btrfs_inode->delalloc_inodes);
3392
3393 btrfs_invalidate_inodes(btrfs_inode->root);
3394 }
3395
3396 spin_unlock(&root->fs_info->delalloc_lock);
3397
3398 return 0;
3399 }
3400
3401 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
3402 struct extent_io_tree *dirty_pages,
3403 int mark)
3404 {
3405 int ret;
3406 struct page *page;
3407 struct inode *btree_inode = root->fs_info->btree_inode;
3408 struct extent_buffer *eb;
3409 u64 start = 0;
3410 u64 end;
3411 u64 offset;
3412 unsigned long index;
3413
3414 while (1) {
3415 ret = find_first_extent_bit(dirty_pages, start, &start, &end,
3416 mark);
3417 if (ret)
3418 break;
3419
3420 clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
3421 while (start <= end) {
3422 index = start >> PAGE_CACHE_SHIFT;
3423 start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
3424 page = find_get_page(btree_inode->i_mapping, index);
3425 if (!page)
3426 continue;
3427 offset = page_offset(page);
3428
3429 spin_lock(&dirty_pages->buffer_lock);
3430 eb = radix_tree_lookup(
3431 &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
3432 offset >> PAGE_CACHE_SHIFT);
3433 spin_unlock(&dirty_pages->buffer_lock);
3434 if (eb) {
3435 ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
3436 &eb->bflags);
3437 atomic_set(&eb->refs, 1);
3438 }
3439 if (PageWriteback(page))
3440 end_page_writeback(page);
3441
3442 lock_page(page);
3443 if (PageDirty(page)) {
3444 clear_page_dirty_for_io(page);
3445 spin_lock_irq(&page->mapping->tree_lock);
3446 radix_tree_tag_clear(&page->mapping->page_tree,
3447 page_index(page),
3448 PAGECACHE_TAG_DIRTY);
3449 spin_unlock_irq(&page->mapping->tree_lock);
3450 }
3451
3452 page->mapping->a_ops->invalidatepage(page, 0);
3453 unlock_page(page);
3454 }
3455 }
3456
3457 return ret;
3458 }
3459
3460 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3461 struct extent_io_tree *pinned_extents)
3462 {
3463 struct extent_io_tree *unpin;
3464 u64 start;
3465 u64 end;
3466 int ret;
3467
3468 unpin = pinned_extents;
3469 while (1) {
3470 ret = find_first_extent_bit(unpin, 0, &start, &end,
3471 EXTENT_DIRTY);
3472 if (ret)
3473 break;
3474
3475 /* opt_discard */
3476 if (btrfs_test_opt(root, DISCARD))
3477 ret = btrfs_error_discard_extent(root, start,
3478 end + 1 - start,
3479 NULL);
3480
3481 clear_extent_dirty(unpin, start, end, GFP_NOFS);
3482 btrfs_error_unpin_extent_range(root, start, end);
3483 cond_resched();
3484 }
3485
3486 return 0;
3487 }
3488
3489 static int btrfs_cleanup_transaction(struct btrfs_root *root)
3490 {
3491 struct btrfs_transaction *t;
3492 LIST_HEAD(list);
3493
3494 WARN_ON(1);
3495
3496 mutex_lock(&root->fs_info->transaction_kthread_mutex);
3497
3498 spin_lock(&root->fs_info->trans_lock);
3499 list_splice_init(&root->fs_info->trans_list, &list);
3500 root->fs_info->trans_no_join = 1;
3501 spin_unlock(&root->fs_info->trans_lock);
3502
3503 while (!list_empty(&list)) {
3504 t = list_entry(list.next, struct btrfs_transaction, list);
3505 if (!t)
3506 break;
3507
3508 btrfs_destroy_ordered_operations(root);
3509
3510 btrfs_destroy_ordered_extents(root);
3511
3512 btrfs_destroy_delayed_refs(t, root);
3513
3514 btrfs_block_rsv_release(root,
3515 &root->fs_info->trans_block_rsv,
3516 t->dirty_pages.dirty_bytes);
3517
3518 /* FIXME: cleanup wait for commit */
3519 t->in_commit = 1;
3520 t->blocked = 1;
3521 if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
3522 wake_up(&root->fs_info->transaction_blocked_wait);
3523
3524 t->blocked = 0;
3525 if (waitqueue_active(&root->fs_info->transaction_wait))
3526 wake_up(&root->fs_info->transaction_wait);
3527
3528 t->commit_done = 1;
3529 if (waitqueue_active(&t->commit_wait))
3530 wake_up(&t->commit_wait);
3531
3532 btrfs_destroy_pending_snapshots(t);
3533
3534 btrfs_destroy_delalloc_inodes(root);
3535
3536 spin_lock(&root->fs_info->trans_lock);
3537 root->fs_info->running_transaction = NULL;
3538 spin_unlock(&root->fs_info->trans_lock);
3539
3540 btrfs_destroy_marked_extents(root, &t->dirty_pages,
3541 EXTENT_DIRTY);
3542
3543 btrfs_destroy_pinned_extent(root,
3544 root->fs_info->pinned_extents);
3545
3546 atomic_set(&t->use_count, 0);
3547 list_del_init(&t->list);
3548 memset(t, 0, sizeof(*t));
3549 kmem_cache_free(btrfs_transaction_cachep, t);
3550 }
3551
3552 spin_lock(&root->fs_info->trans_lock);
3553 root->fs_info->trans_no_join = 0;
3554 spin_unlock(&root->fs_info->trans_lock);
3555 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
3556
3557 return 0;
3558 }
3559
3560 static struct extent_io_ops btree_extent_io_ops = {
3561 .write_cache_pages_lock_hook = btree_lock_page_hook,
3562 .readpage_end_io_hook = btree_readpage_end_io_hook,
3563 .readpage_io_failed_hook = btree_io_failed_hook,
3564 .submit_bio_hook = btree_submit_bio_hook,
3565 /* note we're sharing with inode.c for the merge bio hook */
3566 .merge_bio_hook = btrfs_merge_bio_hook,
3567 };
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree