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Btrfs: extent_map and data=ordered fixes for space balancing
[linux-2.6-block.git] / fs / btrfs / disk-io.c
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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/version.h>
20#include <linux/fs.h>
21#include <linux/blkdev.h>
22#include <linux/scatterlist.h>
23#include <linux/swap.h>
24#include <linux/radix-tree.h>
25#include <linux/writeback.h>
26#include <linux/buffer_head.h> // for block_sync_page
27#include <linux/workqueue.h>
28#include <linux/kthread.h>
29# include <linux/freezer.h>
30#include "crc32c.h"
31#include "ctree.h"
32#include "disk-io.h"
33#include "transaction.h"
34#include "btrfs_inode.h"
35#include "volumes.h"
36#include "print-tree.h"
37#include "async-thread.h"
38#include "locking.h"
39#include "ref-cache.h"
40#include "tree-log.h"
41
42#if 0
43static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
44{
45 if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) {
46 printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n",
47 (unsigned long long)extent_buffer_blocknr(buf),
48 (unsigned long long)btrfs_header_blocknr(buf));
49 return 1;
50 }
51 return 0;
52}
53#endif
54
55static struct extent_io_ops btree_extent_io_ops;
56static void end_workqueue_fn(struct btrfs_work *work);
57
58struct end_io_wq {
59 struct bio *bio;
60 bio_end_io_t *end_io;
61 void *private;
62 struct btrfs_fs_info *info;
63 int error;
64 int metadata;
65 struct list_head list;
66 struct btrfs_work work;
67};
68
69struct async_submit_bio {
70 struct inode *inode;
71 struct bio *bio;
72 struct list_head list;
73 extent_submit_bio_hook_t *submit_bio_hook;
74 int rw;
75 int mirror_num;
76 struct btrfs_work work;
77};
78
79struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
80 size_t page_offset, u64 start, u64 len,
81 int create)
82{
83 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
84 struct extent_map *em;
85 int ret;
86
87 spin_lock(&em_tree->lock);
88 em = lookup_extent_mapping(em_tree, start, len);
89 if (em) {
90 em->bdev =
91 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
92 spin_unlock(&em_tree->lock);
93 goto out;
94 }
95 spin_unlock(&em_tree->lock);
96
97 em = alloc_extent_map(GFP_NOFS);
98 if (!em) {
99 em = ERR_PTR(-ENOMEM);
100 goto out;
101 }
102 em->start = 0;
103 em->len = (u64)-1;
104 em->block_start = 0;
105 em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
106
107 spin_lock(&em_tree->lock);
108 ret = add_extent_mapping(em_tree, em);
109 if (ret == -EEXIST) {
110 u64 failed_start = em->start;
111 u64 failed_len = em->len;
112
113 printk("failed to insert %Lu %Lu -> %Lu into tree\n",
114 em->start, em->len, em->block_start);
115 free_extent_map(em);
116 em = lookup_extent_mapping(em_tree, start, len);
117 if (em) {
118 printk("after failing, found %Lu %Lu %Lu\n",
119 em->start, em->len, em->block_start);
120 ret = 0;
121 } else {
122 em = lookup_extent_mapping(em_tree, failed_start,
123 failed_len);
124 if (em) {
125 printk("double failure lookup gives us "
126 "%Lu %Lu -> %Lu\n", em->start,
127 em->len, em->block_start);
128 free_extent_map(em);
129 }
130 ret = -EIO;
131 }
132 } else if (ret) {
133 free_extent_map(em);
134 em = NULL;
135 }
136 spin_unlock(&em_tree->lock);
137
138 if (ret)
139 em = ERR_PTR(ret);
140out:
141 return em;
142}
143
144u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
145{
146 return btrfs_crc32c(seed, data, len);
147}
148
149void btrfs_csum_final(u32 crc, char *result)
150{
151 *(__le32 *)result = ~cpu_to_le32(crc);
152}
153
154static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
155 int verify)
156{
157 char result[BTRFS_CRC32_SIZE];
158 unsigned long len;
159 unsigned long cur_len;
160 unsigned long offset = BTRFS_CSUM_SIZE;
161 char *map_token = NULL;
162 char *kaddr;
163 unsigned long map_start;
164 unsigned long map_len;
165 int err;
166 u32 crc = ~(u32)0;
167
168 len = buf->len - offset;
169 while(len > 0) {
170 err = map_private_extent_buffer(buf, offset, 32,
171 &map_token, &kaddr,
172 &map_start, &map_len, KM_USER0);
173 if (err) {
174 printk("failed to map extent buffer! %lu\n",
175 offset);
176 return 1;
177 }
178 cur_len = min(len, map_len - (offset - map_start));
179 crc = btrfs_csum_data(root, kaddr + offset - map_start,
180 crc, cur_len);
181 len -= cur_len;
182 offset += cur_len;
183 unmap_extent_buffer(buf, map_token, KM_USER0);
184 }
185 btrfs_csum_final(crc, result);
186
187 if (verify) {
188 /* FIXME, this is not good */
189 if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
190 u32 val;
191 u32 found = 0;
192 memcpy(&found, result, BTRFS_CRC32_SIZE);
193
194 read_extent_buffer(buf, &val, 0, BTRFS_CRC32_SIZE);
195 printk("btrfs: %s checksum verify failed on %llu "
196 "wanted %X found %X level %d\n",
197 root->fs_info->sb->s_id,
198 buf->start, val, found, btrfs_header_level(buf));
199 return 1;
200 }
201 } else {
202 write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE);
203 }
204 return 0;
205}
206
207static int verify_parent_transid(struct extent_io_tree *io_tree,
208 struct extent_buffer *eb, u64 parent_transid)
209{
210 int ret;
211
212 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
213 return 0;
214
215 lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS);
216 if (extent_buffer_uptodate(io_tree, eb) &&
217 btrfs_header_generation(eb) == parent_transid) {
218 ret = 0;
219 goto out;
220 }
221 printk("parent transid verify failed on %llu wanted %llu found %llu\n",
222 (unsigned long long)eb->start,
223 (unsigned long long)parent_transid,
224 (unsigned long long)btrfs_header_generation(eb));
225 ret = 1;
226 clear_extent_buffer_uptodate(io_tree, eb);
227out:
228 unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
229 GFP_NOFS);
230 return ret;
231
232}
233
234static int btree_read_extent_buffer_pages(struct btrfs_root *root,
235 struct extent_buffer *eb,
236 u64 start, u64 parent_transid)
237{
238 struct extent_io_tree *io_tree;
239 int ret;
240 int num_copies = 0;
241 int mirror_num = 0;
242
243 io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
244 while (1) {
245 ret = read_extent_buffer_pages(io_tree, eb, start, 1,
246 btree_get_extent, mirror_num);
247 if (!ret &&
248 !verify_parent_transid(io_tree, eb, parent_transid))
249 return ret;
250printk("read extent buffer pages failed with ret %d mirror no %d\n", ret, mirror_num);
251 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
252 eb->start, eb->len);
253 if (num_copies == 1)
254 return ret;
255
256 mirror_num++;
257 if (mirror_num > num_copies)
258 return ret;
259 }
260 return -EIO;
261}
262
263int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
264{
265 struct extent_io_tree *tree;
266 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
267 u64 found_start;
268 int found_level;
269 unsigned long len;
270 struct extent_buffer *eb;
271 int ret;
272
273 tree = &BTRFS_I(page->mapping->host)->io_tree;
274
275 if (page->private == EXTENT_PAGE_PRIVATE)
276 goto out;
277 if (!page->private)
278 goto out;
279 len = page->private >> 2;
280 if (len == 0) {
281 WARN_ON(1);
282 }
283 eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
284 ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
285 btrfs_header_generation(eb));
286 BUG_ON(ret);
287 found_start = btrfs_header_bytenr(eb);
288 if (found_start != start) {
289 printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n",
290 start, found_start, len);
291 WARN_ON(1);
292 goto err;
293 }
294 if (eb->first_page != page) {
295 printk("bad first page %lu %lu\n", eb->first_page->index,
296 page->index);
297 WARN_ON(1);
298 goto err;
299 }
300 if (!PageUptodate(page)) {
301 printk("csum not up to date page %lu\n", page->index);
302 WARN_ON(1);
303 goto err;
304 }
305 found_level = btrfs_header_level(eb);
306
307 csum_tree_block(root, eb, 0);
308err:
309 free_extent_buffer(eb);
310out:
311 return 0;
312}
313
314int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
315 struct extent_state *state)
316{
317 struct extent_io_tree *tree;
318 u64 found_start;
319 int found_level;
320 unsigned long len;
321 struct extent_buffer *eb;
322 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
323 int ret = 0;
324
325 tree = &BTRFS_I(page->mapping->host)->io_tree;
326 if (page->private == EXTENT_PAGE_PRIVATE)
327 goto out;
328 if (!page->private)
329 goto out;
330 len = page->private >> 2;
331 if (len == 0) {
332 WARN_ON(1);
333 }
334 eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
335
336 found_start = btrfs_header_bytenr(eb);
337 if (found_start != start) {
338 printk("bad tree block start %llu %llu\n",
339 (unsigned long long)found_start,
340 (unsigned long long)eb->start);
341 ret = -EIO;
342 goto err;
343 }
344 if (eb->first_page != page) {
345 printk("bad first page %lu %lu\n", eb->first_page->index,
346 page->index);
347 WARN_ON(1);
348 ret = -EIO;
349 goto err;
350 }
351 if (memcmp_extent_buffer(eb, root->fs_info->fsid,
352 (unsigned long)btrfs_header_fsid(eb),
353 BTRFS_FSID_SIZE)) {
354 printk("bad fsid on block %Lu\n", eb->start);
355 ret = -EIO;
356 goto err;
357 }
358 found_level = btrfs_header_level(eb);
359
360 ret = csum_tree_block(root, eb, 1);
361 if (ret)
362 ret = -EIO;
363
364 end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
365 end = eb->start + end - 1;
366err:
367 free_extent_buffer(eb);
368out:
369 return ret;
370}
371
372static void end_workqueue_bio(struct bio *bio, int err)
373{
374 struct end_io_wq *end_io_wq = bio->bi_private;
375 struct btrfs_fs_info *fs_info;
376
377 fs_info = end_io_wq->info;
378 end_io_wq->error = err;
379 end_io_wq->work.func = end_workqueue_fn;
380 end_io_wq->work.flags = 0;
381 if (bio->bi_rw & (1 << BIO_RW))
382 btrfs_queue_worker(&fs_info->endio_write_workers,
383 &end_io_wq->work);
384 else
385 btrfs_queue_worker(&fs_info->endio_workers, &end_io_wq->work);
386}
387
388int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
389 int metadata)
390{
391 struct end_io_wq *end_io_wq;
392 end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
393 if (!end_io_wq)
394 return -ENOMEM;
395
396 end_io_wq->private = bio->bi_private;
397 end_io_wq->end_io = bio->bi_end_io;
398 end_io_wq->info = info;
399 end_io_wq->error = 0;
400 end_io_wq->bio = bio;
401 end_io_wq->metadata = metadata;
402
403 bio->bi_private = end_io_wq;
404 bio->bi_end_io = end_workqueue_bio;
405 return 0;
406}
407
408unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
409{
410 unsigned long limit = min_t(unsigned long,
411 info->workers.max_workers,
412 info->fs_devices->open_devices);
413 return 256 * limit;
414}
415
416int btrfs_congested_async(struct btrfs_fs_info *info, int iodone)
417{
418 return atomic_read(&info->nr_async_bios) >
419 btrfs_async_submit_limit(info);
420}
421
422static void run_one_async_submit(struct btrfs_work *work)
423{
424 struct btrfs_fs_info *fs_info;
425 struct async_submit_bio *async;
426 int limit;
427
428 async = container_of(work, struct async_submit_bio, work);
429 fs_info = BTRFS_I(async->inode)->root->fs_info;
430
431 limit = btrfs_async_submit_limit(fs_info);
432 limit = limit * 2 / 3;
433
434 atomic_dec(&fs_info->nr_async_submits);
435
436 if (atomic_read(&fs_info->nr_async_submits) < limit &&
437 waitqueue_active(&fs_info->async_submit_wait))
438 wake_up(&fs_info->async_submit_wait);
439
440 async->submit_bio_hook(async->inode, async->rw, async->bio,
441 async->mirror_num);
442 kfree(async);
443}
444
445int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
446 int rw, struct bio *bio, int mirror_num,
447 extent_submit_bio_hook_t *submit_bio_hook)
448{
449 struct async_submit_bio *async;
450 int limit = btrfs_async_submit_limit(fs_info);
451
452 async = kmalloc(sizeof(*async), GFP_NOFS);
453 if (!async)
454 return -ENOMEM;
455
456 async->inode = inode;
457 async->rw = rw;
458 async->bio = bio;
459 async->mirror_num = mirror_num;
460 async->submit_bio_hook = submit_bio_hook;
461 async->work.func = run_one_async_submit;
462 async->work.flags = 0;
463 atomic_inc(&fs_info->nr_async_submits);
464 btrfs_queue_worker(&fs_info->workers, &async->work);
465
466 if (atomic_read(&fs_info->nr_async_submits) > limit) {
467 wait_event_timeout(fs_info->async_submit_wait,
468 (atomic_read(&fs_info->nr_async_submits) < limit),
469 HZ/10);
470
471 wait_event_timeout(fs_info->async_submit_wait,
472 (atomic_read(&fs_info->nr_async_bios) < limit),
473 HZ/10);
474 }
475 return 0;
476}
477
478static int btree_csum_one_bio(struct bio *bio)
479{
480 struct bio_vec *bvec = bio->bi_io_vec;
481 int bio_index = 0;
482 struct btrfs_root *root;
483
484 WARN_ON(bio->bi_vcnt <= 0);
485 while(bio_index < bio->bi_vcnt) {
486 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
487 csum_dirty_buffer(root, bvec->bv_page);
488 bio_index++;
489 bvec++;
490 }
491 return 0;
492}
493
494static int __btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
495 int mirror_num)
496{
497 struct btrfs_root *root = BTRFS_I(inode)->root;
498 u64 offset;
499 int ret;
500
501 offset = bio->bi_sector << 9;
502
503 /*
504 * when we're called for a write, we're already in the async
505 * submission context. Just jump into btrfs_map_bio
506 */
507 if (rw & (1 << BIO_RW)) {
508 btree_csum_one_bio(bio);
509 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
510 mirror_num, 1);
511 }
512
513 /*
514 * called for a read, do the setup so that checksum validation
515 * can happen in the async kernel threads
516 */
517 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 1);
518 BUG_ON(ret);
519
520 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
521}
522
523static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
524 int mirror_num)
525{
526 /*
527 * kthread helpers are used to submit writes so that checksumming
528 * can happen in parallel across all CPUs
529 */
530 if (!(rw & (1 << BIO_RW))) {
531 return __btree_submit_bio_hook(inode, rw, bio, mirror_num);
532 }
533 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
534 inode, rw, bio, mirror_num,
535 __btree_submit_bio_hook);
536}
537
538static int btree_writepage(struct page *page, struct writeback_control *wbc)
539{
540 struct extent_io_tree *tree;
541 tree = &BTRFS_I(page->mapping->host)->io_tree;
542
543 if (current->flags & PF_MEMALLOC) {
544 redirty_page_for_writepage(wbc, page);
545 unlock_page(page);
546 return 0;
547 }
548 return extent_write_full_page(tree, page, btree_get_extent, wbc);
549}
550
551static int btree_writepages(struct address_space *mapping,
552 struct writeback_control *wbc)
553{
554 struct extent_io_tree *tree;
555 tree = &BTRFS_I(mapping->host)->io_tree;
556 if (wbc->sync_mode == WB_SYNC_NONE) {
557 u64 num_dirty;
558 u64 start = 0;
559 unsigned long thresh = 32 * 1024 * 1024;
560
561 if (wbc->for_kupdate)
562 return 0;
563
564 num_dirty = count_range_bits(tree, &start, (u64)-1,
565 thresh, EXTENT_DIRTY);
566 if (num_dirty < thresh) {
567 return 0;
568 }
569 }
570 return extent_writepages(tree, mapping, btree_get_extent, wbc);
571}
572
573int btree_readpage(struct file *file, struct page *page)
574{
575 struct extent_io_tree *tree;
576 tree = &BTRFS_I(page->mapping->host)->io_tree;
577 return extent_read_full_page(tree, page, btree_get_extent);
578}
579
580static int btree_releasepage(struct page *page, gfp_t gfp_flags)
581{
582 struct extent_io_tree *tree;
583 struct extent_map_tree *map;
584 int ret;
585
586 if (PageWriteback(page) || PageDirty(page))
587 return 0;
588
589 tree = &BTRFS_I(page->mapping->host)->io_tree;
590 map = &BTRFS_I(page->mapping->host)->extent_tree;
591
592 ret = try_release_extent_state(map, tree, page, gfp_flags);
593 if (!ret) {
594 return 0;
595 }
596
597 ret = try_release_extent_buffer(tree, page);
598 if (ret == 1) {
599 ClearPagePrivate(page);
600 set_page_private(page, 0);
601 page_cache_release(page);
602 }
603
604 return ret;
605}
606
607static void btree_invalidatepage(struct page *page, unsigned long offset)
608{
609 struct extent_io_tree *tree;
610 tree = &BTRFS_I(page->mapping->host)->io_tree;
611 extent_invalidatepage(tree, page, offset);
612 btree_releasepage(page, GFP_NOFS);
613 if (PagePrivate(page)) {
614 printk("warning page private not zero on page %Lu\n",
615 page_offset(page));
616 ClearPagePrivate(page);
617 set_page_private(page, 0);
618 page_cache_release(page);
619 }
620}
621
622#if 0
623static int btree_writepage(struct page *page, struct writeback_control *wbc)
624{
625 struct buffer_head *bh;
626 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
627 struct buffer_head *head;
628 if (!page_has_buffers(page)) {
629 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
630 (1 << BH_Dirty)|(1 << BH_Uptodate));
631 }
632 head = page_buffers(page);
633 bh = head;
634 do {
635 if (buffer_dirty(bh))
636 csum_tree_block(root, bh, 0);
637 bh = bh->b_this_page;
638 } while (bh != head);
639 return block_write_full_page(page, btree_get_block, wbc);
640}
641#endif
642
643static struct address_space_operations btree_aops = {
644 .readpage = btree_readpage,
645 .writepage = btree_writepage,
646 .writepages = btree_writepages,
647 .releasepage = btree_releasepage,
648 .invalidatepage = btree_invalidatepage,
649 .sync_page = block_sync_page,
650};
651
652int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
653 u64 parent_transid)
654{
655 struct extent_buffer *buf = NULL;
656 struct inode *btree_inode = root->fs_info->btree_inode;
657 int ret = 0;
658
659 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
660 if (!buf)
661 return 0;
662 read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
663 buf, 0, 0, btree_get_extent, 0);
664 free_extent_buffer(buf);
665 return ret;
666}
667
668struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
669 u64 bytenr, u32 blocksize)
670{
671 struct inode *btree_inode = root->fs_info->btree_inode;
672 struct extent_buffer *eb;
673 eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
674 bytenr, blocksize, GFP_NOFS);
675 return eb;
676}
677
678struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
679 u64 bytenr, u32 blocksize)
680{
681 struct inode *btree_inode = root->fs_info->btree_inode;
682 struct extent_buffer *eb;
683
684 eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
685 bytenr, blocksize, NULL, GFP_NOFS);
686 return eb;
687}
688
689
690int btrfs_write_tree_block(struct extent_buffer *buf)
691{
692 return btrfs_fdatawrite_range(buf->first_page->mapping, buf->start,
693 buf->start + buf->len - 1, WB_SYNC_ALL);
694}
695
696int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
697{
698 return btrfs_wait_on_page_writeback_range(buf->first_page->mapping,
699 buf->start, buf->start + buf->len -1);
700}
701
702struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
703 u32 blocksize, u64 parent_transid)
704{
705 struct extent_buffer *buf = NULL;
706 struct inode *btree_inode = root->fs_info->btree_inode;
707 struct extent_io_tree *io_tree;
708 int ret;
709
710 io_tree = &BTRFS_I(btree_inode)->io_tree;
711
712 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
713 if (!buf)
714 return NULL;
715
716 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
717
718 if (ret == 0) {
719 buf->flags |= EXTENT_UPTODATE;
720 } else {
721 WARN_ON(1);
722 }
723 return buf;
724
725}
726
727int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
728 struct extent_buffer *buf)
729{
730 struct inode *btree_inode = root->fs_info->btree_inode;
731 if (btrfs_header_generation(buf) ==
732 root->fs_info->running_transaction->transid) {
733 WARN_ON(!btrfs_tree_locked(buf));
734 clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
735 buf);
736 }
737 return 0;
738}
739
740static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
741 u32 stripesize, struct btrfs_root *root,
742 struct btrfs_fs_info *fs_info,
743 u64 objectid)
744{
745 root->node = NULL;
746 root->inode = NULL;
747 root->commit_root = NULL;
748 root->ref_tree = NULL;
749 root->sectorsize = sectorsize;
750 root->nodesize = nodesize;
751 root->leafsize = leafsize;
752 root->stripesize = stripesize;
753 root->ref_cows = 0;
754 root->track_dirty = 0;
755
756 root->fs_info = fs_info;
757 root->objectid = objectid;
758 root->last_trans = 0;
759 root->highest_inode = 0;
760 root->last_inode_alloc = 0;
761 root->name = NULL;
762 root->in_sysfs = 0;
763
764 INIT_LIST_HEAD(&root->dirty_list);
765 INIT_LIST_HEAD(&root->orphan_list);
766 INIT_LIST_HEAD(&root->dead_list);
767 spin_lock_init(&root->node_lock);
768 spin_lock_init(&root->list_lock);
769 mutex_init(&root->objectid_mutex);
770 mutex_init(&root->log_mutex);
771 extent_io_tree_init(&root->dirty_log_pages,
772 fs_info->btree_inode->i_mapping, GFP_NOFS);
773
774 btrfs_leaf_ref_tree_init(&root->ref_tree_struct);
775 root->ref_tree = &root->ref_tree_struct;
776
777 memset(&root->root_key, 0, sizeof(root->root_key));
778 memset(&root->root_item, 0, sizeof(root->root_item));
779 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
780 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
781 root->defrag_trans_start = fs_info->generation;
782 init_completion(&root->kobj_unregister);
783 root->defrag_running = 0;
784 root->defrag_level = 0;
785 root->root_key.objectid = objectid;
786 return 0;
787}
788
789static int find_and_setup_root(struct btrfs_root *tree_root,
790 struct btrfs_fs_info *fs_info,
791 u64 objectid,
792 struct btrfs_root *root)
793{
794 int ret;
795 u32 blocksize;
796
797 __setup_root(tree_root->nodesize, tree_root->leafsize,
798 tree_root->sectorsize, tree_root->stripesize,
799 root, fs_info, objectid);
800 ret = btrfs_find_last_root(tree_root, objectid,
801 &root->root_item, &root->root_key);
802 BUG_ON(ret);
803
804 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
805 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
806 blocksize, 0);
807 BUG_ON(!root->node);
808 return 0;
809}
810
811int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
812 struct btrfs_fs_info *fs_info)
813{
814 struct extent_buffer *eb;
815 struct btrfs_root *log_root_tree = fs_info->log_root_tree;
816 u64 start = 0;
817 u64 end = 0;
818 int ret;
819
820 if (!log_root_tree)
821 return 0;
822
823 while(1) {
824 ret = find_first_extent_bit(&log_root_tree->dirty_log_pages,
825 0, &start, &end, EXTENT_DIRTY);
826 if (ret)
827 break;
828
829 clear_extent_dirty(&log_root_tree->dirty_log_pages,
830 start, end, GFP_NOFS);
831 }
832 eb = fs_info->log_root_tree->node;
833
834 WARN_ON(btrfs_header_level(eb) != 0);
835 WARN_ON(btrfs_header_nritems(eb) != 0);
836
837 ret = btrfs_free_reserved_extent(fs_info->tree_root,
838 eb->start, eb->len);
839 BUG_ON(ret);
840
841 free_extent_buffer(eb);
842 kfree(fs_info->log_root_tree);
843 fs_info->log_root_tree = NULL;
844 return 0;
845}
846
847int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
848 struct btrfs_fs_info *fs_info)
849{
850 struct btrfs_root *root;
851 struct btrfs_root *tree_root = fs_info->tree_root;
852
853 root = kzalloc(sizeof(*root), GFP_NOFS);
854 if (!root)
855 return -ENOMEM;
856
857 __setup_root(tree_root->nodesize, tree_root->leafsize,
858 tree_root->sectorsize, tree_root->stripesize,
859 root, fs_info, BTRFS_TREE_LOG_OBJECTID);
860
861 root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
862 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
863 root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
864 root->ref_cows = 0;
865
866 root->node = btrfs_alloc_free_block(trans, root, root->leafsize,
867 0, BTRFS_TREE_LOG_OBJECTID,
868 trans->transid, 0, 0, 0);
869
870 btrfs_set_header_nritems(root->node, 0);
871 btrfs_set_header_level(root->node, 0);
872 btrfs_set_header_bytenr(root->node, root->node->start);
873 btrfs_set_header_generation(root->node, trans->transid);
874 btrfs_set_header_owner(root->node, BTRFS_TREE_LOG_OBJECTID);
875
876 write_extent_buffer(root->node, root->fs_info->fsid,
877 (unsigned long)btrfs_header_fsid(root->node),
878 BTRFS_FSID_SIZE);
879 btrfs_mark_buffer_dirty(root->node);
880 btrfs_tree_unlock(root->node);
881 fs_info->log_root_tree = root;
882 return 0;
883}
884
885struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
886 struct btrfs_key *location)
887{
888 struct btrfs_root *root;
889 struct btrfs_fs_info *fs_info = tree_root->fs_info;
890 struct btrfs_path *path;
891 struct extent_buffer *l;
892 u64 highest_inode;
893 u32 blocksize;
894 int ret = 0;
895
896 root = kzalloc(sizeof(*root), GFP_NOFS);
897 if (!root)
898 return ERR_PTR(-ENOMEM);
899 if (location->offset == (u64)-1) {
900 ret = find_and_setup_root(tree_root, fs_info,
901 location->objectid, root);
902 if (ret) {
903 kfree(root);
904 return ERR_PTR(ret);
905 }
906 goto insert;
907 }
908
909 __setup_root(tree_root->nodesize, tree_root->leafsize,
910 tree_root->sectorsize, tree_root->stripesize,
911 root, fs_info, location->objectid);
912
913 path = btrfs_alloc_path();
914 BUG_ON(!path);
915 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
916 if (ret != 0) {
917 if (ret > 0)
918 ret = -ENOENT;
919 goto out;
920 }
921 l = path->nodes[0];
922 read_extent_buffer(l, &root->root_item,
923 btrfs_item_ptr_offset(l, path->slots[0]),
924 sizeof(root->root_item));
925 memcpy(&root->root_key, location, sizeof(*location));
926 ret = 0;
927out:
928 btrfs_release_path(root, path);
929 btrfs_free_path(path);
930 if (ret) {
931 kfree(root);
932 return ERR_PTR(ret);
933 }
934 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
935 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
936 blocksize, 0);
937 BUG_ON(!root->node);
938insert:
939 if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
940 root->ref_cows = 1;
941 ret = btrfs_find_highest_inode(root, &highest_inode);
942 if (ret == 0) {
943 root->highest_inode = highest_inode;
944 root->last_inode_alloc = highest_inode;
945 }
946 }
947 return root;
948}
949
950struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
951 u64 root_objectid)
952{
953 struct btrfs_root *root;
954
955 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID)
956 return fs_info->tree_root;
957 if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID)
958 return fs_info->extent_root;
959
960 root = radix_tree_lookup(&fs_info->fs_roots_radix,
961 (unsigned long)root_objectid);
962 return root;
963}
964
965struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
966 struct btrfs_key *location)
967{
968 struct btrfs_root *root;
969 int ret;
970
971 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
972 return fs_info->tree_root;
973 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
974 return fs_info->extent_root;
975 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
976 return fs_info->chunk_root;
977 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
978 return fs_info->dev_root;
979
980 root = radix_tree_lookup(&fs_info->fs_roots_radix,
981 (unsigned long)location->objectid);
982 if (root)
983 return root;
984
985 root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
986 if (IS_ERR(root))
987 return root;
988 ret = radix_tree_insert(&fs_info->fs_roots_radix,
989 (unsigned long)root->root_key.objectid,
990 root);
991 if (ret) {
992 free_extent_buffer(root->node);
993 kfree(root);
994 return ERR_PTR(ret);
995 }
996 ret = btrfs_find_dead_roots(fs_info->tree_root,
997 root->root_key.objectid, root);
998 BUG_ON(ret);
999
1000 return root;
1001}
1002
1003struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
1004 struct btrfs_key *location,
1005 const char *name, int namelen)
1006{
1007 struct btrfs_root *root;
1008 int ret;
1009
1010 root = btrfs_read_fs_root_no_name(fs_info, location);
1011 if (!root)
1012 return NULL;
1013
1014 if (root->in_sysfs)
1015 return root;
1016
1017 ret = btrfs_set_root_name(root, name, namelen);
1018 if (ret) {
1019 free_extent_buffer(root->node);
1020 kfree(root);
1021 return ERR_PTR(ret);
1022 }
1023
1024 ret = btrfs_sysfs_add_root(root);
1025 if (ret) {
1026 free_extent_buffer(root->node);
1027 kfree(root->name);
1028 kfree(root);
1029 return ERR_PTR(ret);
1030 }
1031 root->in_sysfs = 1;
1032 return root;
1033}
1034#if 0
1035static int add_hasher(struct btrfs_fs_info *info, char *type) {
1036 struct btrfs_hasher *hasher;
1037
1038 hasher = kmalloc(sizeof(*hasher), GFP_NOFS);
1039 if (!hasher)
1040 return -ENOMEM;
1041 hasher->hash_tfm = crypto_alloc_hash(type, 0, CRYPTO_ALG_ASYNC);
1042 if (!hasher->hash_tfm) {
1043 kfree(hasher);
1044 return -EINVAL;
1045 }
1046 spin_lock(&info->hash_lock);
1047 list_add(&hasher->list, &info->hashers);
1048 spin_unlock(&info->hash_lock);
1049 return 0;
1050}
1051#endif
1052
1053static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1054{
1055 struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1056 int ret = 0;
1057 struct list_head *cur;
1058 struct btrfs_device *device;
1059 struct backing_dev_info *bdi;
1060
1061 if ((bdi_bits & (1 << BDI_write_congested)) &&
1062 btrfs_congested_async(info, 0))
1063 return 1;
1064
1065 list_for_each(cur, &info->fs_devices->devices) {
1066 device = list_entry(cur, struct btrfs_device, dev_list);
1067 if (!device->bdev)
1068 continue;
1069 bdi = blk_get_backing_dev_info(device->bdev);
1070 if (bdi && bdi_congested(bdi, bdi_bits)) {
1071 ret = 1;
1072 break;
1073 }
1074 }
1075 return ret;
1076}
1077
1078/*
1079 * this unplugs every device on the box, and it is only used when page
1080 * is null
1081 */
1082static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
1083{
1084 struct list_head *cur;
1085 struct btrfs_device *device;
1086 struct btrfs_fs_info *info;
1087
1088 info = (struct btrfs_fs_info *)bdi->unplug_io_data;
1089 list_for_each(cur, &info->fs_devices->devices) {
1090 device = list_entry(cur, struct btrfs_device, dev_list);
1091 bdi = blk_get_backing_dev_info(device->bdev);
1092 if (bdi->unplug_io_fn) {
1093 bdi->unplug_io_fn(bdi, page);
1094 }
1095 }
1096}
1097
1098void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
1099{
1100 struct inode *inode;
1101 struct extent_map_tree *em_tree;
1102 struct extent_map *em;
1103 struct address_space *mapping;
1104 u64 offset;
1105
1106 /* the generic O_DIRECT read code does this */
1107 if (!page) {
1108 __unplug_io_fn(bdi, page);
1109 return;
1110 }
1111
1112 /*
1113 * page->mapping may change at any time. Get a consistent copy
1114 * and use that for everything below
1115 */
1116 smp_mb();
1117 mapping = page->mapping;
1118 if (!mapping)
1119 return;
1120
1121 inode = mapping->host;
1122 offset = page_offset(page);
1123
1124 em_tree = &BTRFS_I(inode)->extent_tree;
1125 spin_lock(&em_tree->lock);
1126 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
1127 spin_unlock(&em_tree->lock);
1128 if (!em) {
1129 __unplug_io_fn(bdi, page);
1130 return;
1131 }
1132
1133 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1134 free_extent_map(em);
1135 __unplug_io_fn(bdi, page);
1136 return;
1137 }
1138 offset = offset - em->start;
1139 btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree,
1140 em->block_start + offset, page);
1141 free_extent_map(em);
1142}
1143
1144static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1145{
1146 bdi_init(bdi);
1147 bdi->ra_pages = default_backing_dev_info.ra_pages;
1148 bdi->state = 0;
1149 bdi->capabilities = default_backing_dev_info.capabilities;
1150 bdi->unplug_io_fn = btrfs_unplug_io_fn;
1151 bdi->unplug_io_data = info;
1152 bdi->congested_fn = btrfs_congested_fn;
1153 bdi->congested_data = info;
1154 return 0;
1155}
1156
1157static int bio_ready_for_csum(struct bio *bio)
1158{
1159 u64 length = 0;
1160 u64 buf_len = 0;
1161 u64 start = 0;
1162 struct page *page;
1163 struct extent_io_tree *io_tree = NULL;
1164 struct btrfs_fs_info *info = NULL;
1165 struct bio_vec *bvec;
1166 int i;
1167 int ret;
1168
1169 bio_for_each_segment(bvec, bio, i) {
1170 page = bvec->bv_page;
1171 if (page->private == EXTENT_PAGE_PRIVATE) {
1172 length += bvec->bv_len;
1173 continue;
1174 }
1175 if (!page->private) {
1176 length += bvec->bv_len;
1177 continue;
1178 }
1179 length = bvec->bv_len;
1180 buf_len = page->private >> 2;
1181 start = page_offset(page) + bvec->bv_offset;
1182 io_tree = &BTRFS_I(page->mapping->host)->io_tree;
1183 info = BTRFS_I(page->mapping->host)->root->fs_info;
1184 }
1185 /* are we fully contained in this bio? */
1186 if (buf_len <= length)
1187 return 1;
1188
1189 ret = extent_range_uptodate(io_tree, start + length,
1190 start + buf_len - 1);
1191 if (ret == 1)
1192 return ret;
1193 return ret;
1194}
1195
1196/*
1197 * called by the kthread helper functions to finally call the bio end_io
1198 * functions. This is where read checksum verification actually happens
1199 */
1200static void end_workqueue_fn(struct btrfs_work *work)
1201{
1202 struct bio *bio;
1203 struct end_io_wq *end_io_wq;
1204 struct btrfs_fs_info *fs_info;
1205 int error;
1206
1207 end_io_wq = container_of(work, struct end_io_wq, work);
1208 bio = end_io_wq->bio;
1209 fs_info = end_io_wq->info;
1210
1211 /* metadata bios are special because the whole tree block must
1212 * be checksummed at once. This makes sure the entire block is in
1213 * ram and up to date before trying to verify things. For
1214 * blocksize <= pagesize, it is basically a noop
1215 */
1216 if (end_io_wq->metadata && !bio_ready_for_csum(bio)) {
1217 btrfs_queue_worker(&fs_info->endio_workers,
1218 &end_io_wq->work);
1219 return;
1220 }
1221 error = end_io_wq->error;
1222 bio->bi_private = end_io_wq->private;
1223 bio->bi_end_io = end_io_wq->end_io;
1224 kfree(end_io_wq);
1225 bio_endio(bio, error);
1226}
1227
1228static int cleaner_kthread(void *arg)
1229{
1230 struct btrfs_root *root = arg;
1231
1232 do {
1233 smp_mb();
1234 if (root->fs_info->closing)
1235 break;
1236
1237 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1238 mutex_lock(&root->fs_info->cleaner_mutex);
1239 btrfs_clean_old_snapshots(root);
1240 mutex_unlock(&root->fs_info->cleaner_mutex);
1241
1242 if (freezing(current)) {
1243 refrigerator();
1244 } else {
1245 smp_mb();
1246 if (root->fs_info->closing)
1247 break;
1248 set_current_state(TASK_INTERRUPTIBLE);
1249 schedule();
1250 __set_current_state(TASK_RUNNING);
1251 }
1252 } while (!kthread_should_stop());
1253 return 0;
1254}
1255
1256static int transaction_kthread(void *arg)
1257{
1258 struct btrfs_root *root = arg;
1259 struct btrfs_trans_handle *trans;
1260 struct btrfs_transaction *cur;
1261 unsigned long now;
1262 unsigned long delay;
1263 int ret;
1264
1265 do {
1266 smp_mb();
1267 if (root->fs_info->closing)
1268 break;
1269
1270 delay = HZ * 30;
1271 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1272 mutex_lock(&root->fs_info->transaction_kthread_mutex);
1273
1274 if (root->fs_info->total_ref_cache_size > 20 * 1024 * 1024) {
1275 printk("btrfs: total reference cache size %Lu\n",
1276 root->fs_info->total_ref_cache_size);
1277 }
1278
1279 mutex_lock(&root->fs_info->trans_mutex);
1280 cur = root->fs_info->running_transaction;
1281 if (!cur) {
1282 mutex_unlock(&root->fs_info->trans_mutex);
1283 goto sleep;
1284 }
1285
1286 now = get_seconds();
1287 if (now < cur->start_time || now - cur->start_time < 30) {
1288 mutex_unlock(&root->fs_info->trans_mutex);
1289 delay = HZ * 5;
1290 goto sleep;
1291 }
1292 mutex_unlock(&root->fs_info->trans_mutex);
1293 trans = btrfs_start_transaction(root, 1);
1294 ret = btrfs_commit_transaction(trans, root);
1295sleep:
1296 wake_up_process(root->fs_info->cleaner_kthread);
1297 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1298
1299 if (freezing(current)) {
1300 refrigerator();
1301 } else {
1302 if (root->fs_info->closing)
1303 break;
1304 set_current_state(TASK_INTERRUPTIBLE);
1305 schedule_timeout(delay);
1306 __set_current_state(TASK_RUNNING);
1307 }
1308 } while (!kthread_should_stop());
1309 return 0;
1310}
1311
1312struct btrfs_root *open_ctree(struct super_block *sb,
1313 struct btrfs_fs_devices *fs_devices,
1314 char *options)
1315{
1316 u32 sectorsize;
1317 u32 nodesize;
1318 u32 leafsize;
1319 u32 blocksize;
1320 u32 stripesize;
1321 struct buffer_head *bh;
1322 struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root),
1323 GFP_NOFS);
1324 struct btrfs_root *tree_root = kzalloc(sizeof(struct btrfs_root),
1325 GFP_NOFS);
1326 struct btrfs_fs_info *fs_info = kzalloc(sizeof(*fs_info),
1327 GFP_NOFS);
1328 struct btrfs_root *chunk_root = kzalloc(sizeof(struct btrfs_root),
1329 GFP_NOFS);
1330 struct btrfs_root *dev_root = kzalloc(sizeof(struct btrfs_root),
1331 GFP_NOFS);
1332 struct btrfs_root *log_tree_root;
1333
1334 int ret;
1335 int err = -EINVAL;
1336
1337 struct btrfs_super_block *disk_super;
1338
1339 if (!extent_root || !tree_root || !fs_info) {
1340 err = -ENOMEM;
1341 goto fail;
1342 }
1343 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
1344 INIT_LIST_HEAD(&fs_info->trans_list);
1345 INIT_LIST_HEAD(&fs_info->dead_roots);
1346 INIT_LIST_HEAD(&fs_info->hashers);
1347 INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1348 spin_lock_init(&fs_info->hash_lock);
1349 spin_lock_init(&fs_info->delalloc_lock);
1350 spin_lock_init(&fs_info->new_trans_lock);
1351 spin_lock_init(&fs_info->ref_cache_lock);
1352
1353 init_completion(&fs_info->kobj_unregister);
1354 fs_info->tree_root = tree_root;
1355 fs_info->extent_root = extent_root;
1356 fs_info->chunk_root = chunk_root;
1357 fs_info->dev_root = dev_root;
1358 fs_info->fs_devices = fs_devices;
1359 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1360 INIT_LIST_HEAD(&fs_info->space_info);
1361 btrfs_mapping_init(&fs_info->mapping_tree);
1362 atomic_set(&fs_info->nr_async_submits, 0);
1363 atomic_set(&fs_info->nr_async_bios, 0);
1364 atomic_set(&fs_info->throttles, 0);
1365 atomic_set(&fs_info->throttle_gen, 0);
1366 fs_info->sb = sb;
1367 fs_info->max_extent = (u64)-1;
1368 fs_info->max_inline = 8192 * 1024;
1369 setup_bdi(fs_info, &fs_info->bdi);
1370 fs_info->btree_inode = new_inode(sb);
1371 fs_info->btree_inode->i_ino = 1;
1372 fs_info->btree_inode->i_nlink = 1;
1373 fs_info->thread_pool_size = min(num_online_cpus() + 2, 8);
1374
1375 INIT_LIST_HEAD(&fs_info->ordered_extents);
1376 spin_lock_init(&fs_info->ordered_extent_lock);
1377
1378 sb->s_blocksize = 4096;
1379 sb->s_blocksize_bits = blksize_bits(4096);
1380
1381 /*
1382 * we set the i_size on the btree inode to the max possible int.
1383 * the real end of the address space is determined by all of
1384 * the devices in the system
1385 */
1386 fs_info->btree_inode->i_size = OFFSET_MAX;
1387 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
1388 fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
1389
1390 extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
1391 fs_info->btree_inode->i_mapping,
1392 GFP_NOFS);
1393 extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
1394 GFP_NOFS);
1395
1396 BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
1397
1398 spin_lock_init(&fs_info->block_group_cache_lock);
1399 fs_info->block_group_cache_tree.rb_node = NULL;
1400
1401 extent_io_tree_init(&fs_info->pinned_extents,
1402 fs_info->btree_inode->i_mapping, GFP_NOFS);
1403 extent_io_tree_init(&fs_info->pending_del,
1404 fs_info->btree_inode->i_mapping, GFP_NOFS);
1405 extent_io_tree_init(&fs_info->extent_ins,
1406 fs_info->btree_inode->i_mapping, GFP_NOFS);
1407 fs_info->do_barriers = 1;
1408
1409 btrfs_leaf_ref_tree_init(&fs_info->shared_ref_tree);
1410
1411 BTRFS_I(fs_info->btree_inode)->root = tree_root;
1412 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
1413 sizeof(struct btrfs_key));
1414 insert_inode_hash(fs_info->btree_inode);
1415
1416 mutex_init(&fs_info->trans_mutex);
1417 mutex_init(&fs_info->tree_log_mutex);
1418 mutex_init(&fs_info->drop_mutex);
1419 mutex_init(&fs_info->alloc_mutex);
1420 mutex_init(&fs_info->chunk_mutex);
1421 mutex_init(&fs_info->transaction_kthread_mutex);
1422 mutex_init(&fs_info->cleaner_mutex);
1423 mutex_init(&fs_info->volume_mutex);
1424 init_waitqueue_head(&fs_info->transaction_throttle);
1425 init_waitqueue_head(&fs_info->transaction_wait);
1426 init_waitqueue_head(&fs_info->async_submit_wait);
1427 init_waitqueue_head(&fs_info->tree_log_wait);
1428 atomic_set(&fs_info->tree_log_commit, 0);
1429 atomic_set(&fs_info->tree_log_writers, 0);
1430 fs_info->tree_log_transid = 0;
1431
1432#if 0
1433 ret = add_hasher(fs_info, "crc32c");
1434 if (ret) {
1435 printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
1436 err = -ENOMEM;
1437 goto fail_iput;
1438 }
1439#endif
1440 __setup_root(4096, 4096, 4096, 4096, tree_root,
1441 fs_info, BTRFS_ROOT_TREE_OBJECTID);
1442
1443
1444 bh = __bread(fs_devices->latest_bdev,
1445 BTRFS_SUPER_INFO_OFFSET / 4096, 4096);
1446 if (!bh)
1447 goto fail_iput;
1448
1449 memcpy(&fs_info->super_copy, bh->b_data, sizeof(fs_info->super_copy));
1450 brelse(bh);
1451
1452 memcpy(fs_info->fsid, fs_info->super_copy.fsid, BTRFS_FSID_SIZE);
1453
1454 disk_super = &fs_info->super_copy;
1455 if (!btrfs_super_root(disk_super))
1456 goto fail_sb_buffer;
1457
1458 err = btrfs_parse_options(tree_root, options);
1459 if (err)
1460 goto fail_sb_buffer;
1461
1462 /*
1463 * we need to start all the end_io workers up front because the
1464 * queue work function gets called at interrupt time, and so it
1465 * cannot dynamically grow.
1466 */
1467 btrfs_init_workers(&fs_info->workers, "worker",
1468 fs_info->thread_pool_size);
1469 btrfs_init_workers(&fs_info->submit_workers, "submit",
1470 min_t(u64, fs_devices->num_devices,
1471 fs_info->thread_pool_size));
1472
1473 /* a higher idle thresh on the submit workers makes it much more
1474 * likely that bios will be send down in a sane order to the
1475 * devices
1476 */
1477 fs_info->submit_workers.idle_thresh = 64;
1478
1479 /* fs_info->workers is responsible for checksumming file data
1480 * blocks and metadata. Using a larger idle thresh allows each
1481 * worker thread to operate on things in roughly the order they
1482 * were sent by the writeback daemons, improving overall locality
1483 * of the IO going down the pipe.
1484 */
1485 fs_info->workers.idle_thresh = 128;
1486
1487 btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1);
1488 btrfs_init_workers(&fs_info->endio_workers, "endio",
1489 fs_info->thread_pool_size);
1490 btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
1491 fs_info->thread_pool_size);
1492
1493 /*
1494 * endios are largely parallel and should have a very
1495 * low idle thresh
1496 */
1497 fs_info->endio_workers.idle_thresh = 4;
1498 fs_info->endio_write_workers.idle_thresh = 64;
1499
1500 btrfs_start_workers(&fs_info->workers, 1);
1501 btrfs_start_workers(&fs_info->submit_workers, 1);
1502 btrfs_start_workers(&fs_info->fixup_workers, 1);
1503 btrfs_start_workers(&fs_info->endio_workers, fs_info->thread_pool_size);
1504 btrfs_start_workers(&fs_info->endio_write_workers,
1505 fs_info->thread_pool_size);
1506
1507 err = -EINVAL;
1508 if (btrfs_super_num_devices(disk_super) > fs_devices->open_devices) {
1509 printk("Btrfs: wanted %llu devices, but found %llu\n",
1510 (unsigned long long)btrfs_super_num_devices(disk_super),
1511 (unsigned long long)fs_devices->open_devices);
1512 if (btrfs_test_opt(tree_root, DEGRADED))
1513 printk("continuing in degraded mode\n");
1514 else {
1515 goto fail_sb_buffer;
1516 }
1517 }
1518
1519 fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
1520
1521 nodesize = btrfs_super_nodesize(disk_super);
1522 leafsize = btrfs_super_leafsize(disk_super);
1523 sectorsize = btrfs_super_sectorsize(disk_super);
1524 stripesize = btrfs_super_stripesize(disk_super);
1525 tree_root->nodesize = nodesize;
1526 tree_root->leafsize = leafsize;
1527 tree_root->sectorsize = sectorsize;
1528 tree_root->stripesize = stripesize;
1529
1530 sb->s_blocksize = sectorsize;
1531 sb->s_blocksize_bits = blksize_bits(sectorsize);
1532
1533 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
1534 sizeof(disk_super->magic))) {
1535 printk("btrfs: valid FS not found on %s\n", sb->s_id);
1536 goto fail_sb_buffer;
1537 }
1538
1539 mutex_lock(&fs_info->chunk_mutex);
1540 ret = btrfs_read_sys_array(tree_root);
1541 mutex_unlock(&fs_info->chunk_mutex);
1542 if (ret) {
1543 printk("btrfs: failed to read the system array on %s\n",
1544 sb->s_id);
1545 goto fail_sys_array;
1546 }
1547
1548 blocksize = btrfs_level_size(tree_root,
1549 btrfs_super_chunk_root_level(disk_super));
1550
1551 __setup_root(nodesize, leafsize, sectorsize, stripesize,
1552 chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1553
1554 chunk_root->node = read_tree_block(chunk_root,
1555 btrfs_super_chunk_root(disk_super),
1556 blocksize, 0);
1557 BUG_ON(!chunk_root->node);
1558
1559 read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
1560 (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
1561 BTRFS_UUID_SIZE);
1562
1563 mutex_lock(&fs_info->chunk_mutex);
1564 ret = btrfs_read_chunk_tree(chunk_root);
1565 mutex_unlock(&fs_info->chunk_mutex);
1566 BUG_ON(ret);
1567
1568 btrfs_close_extra_devices(fs_devices);
1569
1570 blocksize = btrfs_level_size(tree_root,
1571 btrfs_super_root_level(disk_super));
1572
1573
1574 tree_root->node = read_tree_block(tree_root,
1575 btrfs_super_root(disk_super),
1576 blocksize, 0);
1577 if (!tree_root->node)
1578 goto fail_sb_buffer;
1579
1580
1581 ret = find_and_setup_root(tree_root, fs_info,
1582 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
1583 if (ret)
1584 goto fail_tree_root;
1585 extent_root->track_dirty = 1;
1586
1587 ret = find_and_setup_root(tree_root, fs_info,
1588 BTRFS_DEV_TREE_OBJECTID, dev_root);
1589 dev_root->track_dirty = 1;
1590
1591 if (ret)
1592 goto fail_extent_root;
1593
1594 btrfs_read_block_groups(extent_root);
1595
1596 fs_info->generation = btrfs_super_generation(disk_super) + 1;
1597 fs_info->data_alloc_profile = (u64)-1;
1598 fs_info->metadata_alloc_profile = (u64)-1;
1599 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
1600 fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
1601 "btrfs-cleaner");
1602 if (!fs_info->cleaner_kthread)
1603 goto fail_extent_root;
1604
1605 fs_info->transaction_kthread = kthread_run(transaction_kthread,
1606 tree_root,
1607 "btrfs-transaction");
1608 if (!fs_info->transaction_kthread)
1609 goto fail_cleaner;
1610
1611 if (btrfs_super_log_root(disk_super) != 0) {
1612 u32 blocksize;
1613 u64 bytenr = btrfs_super_log_root(disk_super);
1614
1615 blocksize =
1616 btrfs_level_size(tree_root,
1617 btrfs_super_log_root_level(disk_super));
1618
1619 log_tree_root = kzalloc(sizeof(struct btrfs_root),
1620 GFP_NOFS);
1621
1622 __setup_root(nodesize, leafsize, sectorsize, stripesize,
1623 log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1624
1625 log_tree_root->node = read_tree_block(tree_root, bytenr,
1626 blocksize, 0);
1627 ret = btrfs_recover_log_trees(log_tree_root);
1628 BUG_ON(ret);
1629 }
1630 fs_info->last_trans_committed = btrfs_super_generation(disk_super);
1631 return tree_root;
1632
1633fail_cleaner:
1634 kthread_stop(fs_info->cleaner_kthread);
1635fail_extent_root:
1636 free_extent_buffer(extent_root->node);
1637fail_tree_root:
1638 free_extent_buffer(tree_root->node);
1639fail_sys_array:
1640fail_sb_buffer:
1641 btrfs_stop_workers(&fs_info->fixup_workers);
1642 btrfs_stop_workers(&fs_info->workers);
1643 btrfs_stop_workers(&fs_info->endio_workers);
1644 btrfs_stop_workers(&fs_info->endio_write_workers);
1645 btrfs_stop_workers(&fs_info->submit_workers);
1646fail_iput:
1647 iput(fs_info->btree_inode);
1648fail:
1649 btrfs_close_devices(fs_info->fs_devices);
1650 btrfs_mapping_tree_free(&fs_info->mapping_tree);
1651
1652 kfree(extent_root);
1653 kfree(tree_root);
1654 bdi_destroy(&fs_info->bdi);
1655 kfree(fs_info);
1656 return ERR_PTR(err);
1657}
1658
1659static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
1660{
1661 char b[BDEVNAME_SIZE];
1662
1663 if (uptodate) {
1664 set_buffer_uptodate(bh);
1665 } else {
1666 if (!buffer_eopnotsupp(bh) && printk_ratelimit()) {
1667 printk(KERN_WARNING "lost page write due to "
1668 "I/O error on %s\n",
1669 bdevname(bh->b_bdev, b));
1670 }
1671 /* note, we dont' set_buffer_write_io_error because we have
1672 * our own ways of dealing with the IO errors
1673 */
1674 clear_buffer_uptodate(bh);
1675 }
1676 unlock_buffer(bh);
1677 put_bh(bh);
1678}
1679
1680int write_all_supers(struct btrfs_root *root)
1681{
1682 struct list_head *cur;
1683 struct list_head *head = &root->fs_info->fs_devices->devices;
1684 struct btrfs_device *dev;
1685 struct btrfs_super_block *sb;
1686 struct btrfs_dev_item *dev_item;
1687 struct buffer_head *bh;
1688 int ret;
1689 int do_barriers;
1690 int max_errors;
1691 int total_errors = 0;
1692 u32 crc;
1693 u64 flags;
1694
1695 max_errors = btrfs_super_num_devices(&root->fs_info->super_copy) - 1;
1696 do_barriers = !btrfs_test_opt(root, NOBARRIER);
1697
1698 sb = &root->fs_info->super_for_commit;
1699 dev_item = &sb->dev_item;
1700 list_for_each(cur, head) {
1701 dev = list_entry(cur, struct btrfs_device, dev_list);
1702 if (!dev->bdev) {
1703 total_errors++;
1704 continue;
1705 }
1706 if (!dev->in_fs_metadata)
1707 continue;
1708
1709 btrfs_set_stack_device_type(dev_item, dev->type);
1710 btrfs_set_stack_device_id(dev_item, dev->devid);
1711 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1712 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1713 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1714 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1715 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1716 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1717 flags = btrfs_super_flags(sb);
1718 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1719
1720
1721 crc = ~(u32)0;
1722 crc = btrfs_csum_data(root, (char *)sb + BTRFS_CSUM_SIZE, crc,
1723 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1724 btrfs_csum_final(crc, sb->csum);
1725
1726 bh = __getblk(dev->bdev, BTRFS_SUPER_INFO_OFFSET / 4096,
1727 BTRFS_SUPER_INFO_SIZE);
1728
1729 memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
1730 dev->pending_io = bh;
1731
1732 get_bh(bh);
1733 set_buffer_uptodate(bh);
1734 lock_buffer(bh);
1735 bh->b_end_io = btrfs_end_buffer_write_sync;
1736
1737 if (do_barriers && dev->barriers) {
1738 ret = submit_bh(WRITE_BARRIER, bh);
1739 if (ret == -EOPNOTSUPP) {
1740 printk("btrfs: disabling barriers on dev %s\n",
1741 dev->name);
1742 set_buffer_uptodate(bh);
1743 dev->barriers = 0;
1744 get_bh(bh);
1745 lock_buffer(bh);
1746 ret = submit_bh(WRITE, bh);
1747 }
1748 } else {
1749 ret = submit_bh(WRITE, bh);
1750 }
1751 if (ret)
1752 total_errors++;
1753 }
1754 if (total_errors > max_errors) {
1755 printk("btrfs: %d errors while writing supers\n", total_errors);
1756 BUG();
1757 }
1758 total_errors = 0;
1759
1760 list_for_each(cur, head) {
1761 dev = list_entry(cur, struct btrfs_device, dev_list);
1762 if (!dev->bdev)
1763 continue;
1764 if (!dev->in_fs_metadata)
1765 continue;
1766
1767 BUG_ON(!dev->pending_io);
1768 bh = dev->pending_io;
1769 wait_on_buffer(bh);
1770 if (!buffer_uptodate(dev->pending_io)) {
1771 if (do_barriers && dev->barriers) {
1772 printk("btrfs: disabling barriers on dev %s\n",
1773 dev->name);
1774 set_buffer_uptodate(bh);
1775 get_bh(bh);
1776 lock_buffer(bh);
1777 dev->barriers = 0;
1778 ret = submit_bh(WRITE, bh);
1779 BUG_ON(ret);
1780 wait_on_buffer(bh);
1781 if (!buffer_uptodate(bh))
1782 total_errors++;
1783 } else {
1784 total_errors++;
1785 }
1786
1787 }
1788 dev->pending_io = NULL;
1789 brelse(bh);
1790 }
1791 if (total_errors > max_errors) {
1792 printk("btrfs: %d errors while writing supers\n", total_errors);
1793 BUG();
1794 }
1795 return 0;
1796}
1797
1798int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
1799 *root)
1800{
1801 int ret;
1802
1803 ret = write_all_supers(root);
1804 return ret;
1805}
1806
1807int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
1808{
1809 radix_tree_delete(&fs_info->fs_roots_radix,
1810 (unsigned long)root->root_key.objectid);
1811 if (root->in_sysfs)
1812 btrfs_sysfs_del_root(root);
1813 if (root->inode)
1814 iput(root->inode);
1815 if (root->node)
1816 free_extent_buffer(root->node);
1817 if (root->commit_root)
1818 free_extent_buffer(root->commit_root);
1819 if (root->name)
1820 kfree(root->name);
1821 kfree(root);
1822 return 0;
1823}
1824
1825static int del_fs_roots(struct btrfs_fs_info *fs_info)
1826{
1827 int ret;
1828 struct btrfs_root *gang[8];
1829 int i;
1830
1831 while(1) {
1832 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
1833 (void **)gang, 0,
1834 ARRAY_SIZE(gang));
1835 if (!ret)
1836 break;
1837 for (i = 0; i < ret; i++)
1838 btrfs_free_fs_root(fs_info, gang[i]);
1839 }
1840 return 0;
1841}
1842
1843int close_ctree(struct btrfs_root *root)
1844{
1845 int ret;
1846 struct btrfs_trans_handle *trans;
1847 struct btrfs_fs_info *fs_info = root->fs_info;
1848
1849 fs_info->closing = 1;
1850 smp_mb();
1851
1852 kthread_stop(root->fs_info->transaction_kthread);
1853 kthread_stop(root->fs_info->cleaner_kthread);
1854
1855 btrfs_clean_old_snapshots(root);
1856 trans = btrfs_start_transaction(root, 1);
1857 ret = btrfs_commit_transaction(trans, root);
1858 /* run commit again to drop the original snapshot */
1859 trans = btrfs_start_transaction(root, 1);
1860 btrfs_commit_transaction(trans, root);
1861 ret = btrfs_write_and_wait_transaction(NULL, root);
1862 BUG_ON(ret);
1863
1864 write_ctree_super(NULL, root);
1865
1866 if (fs_info->delalloc_bytes) {
1867 printk("btrfs: at unmount delalloc count %Lu\n",
1868 fs_info->delalloc_bytes);
1869 }
1870 if (fs_info->total_ref_cache_size) {
1871 printk("btrfs: at umount reference cache size %Lu\n",
1872 fs_info->total_ref_cache_size);
1873 }
1874
1875 if (fs_info->extent_root->node)
1876 free_extent_buffer(fs_info->extent_root->node);
1877
1878 if (fs_info->tree_root->node)
1879 free_extent_buffer(fs_info->tree_root->node);
1880
1881 if (root->fs_info->chunk_root->node);
1882 free_extent_buffer(root->fs_info->chunk_root->node);
1883
1884 if (root->fs_info->dev_root->node);
1885 free_extent_buffer(root->fs_info->dev_root->node);
1886
1887 btrfs_free_block_groups(root->fs_info);
1888 fs_info->closing = 2;
1889 del_fs_roots(fs_info);
1890
1891 filemap_write_and_wait(fs_info->btree_inode->i_mapping);
1892
1893 truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
1894
1895 btrfs_stop_workers(&fs_info->fixup_workers);
1896 btrfs_stop_workers(&fs_info->workers);
1897 btrfs_stop_workers(&fs_info->endio_workers);
1898 btrfs_stop_workers(&fs_info->endio_write_workers);
1899 btrfs_stop_workers(&fs_info->submit_workers);
1900
1901 iput(fs_info->btree_inode);
1902#if 0
1903 while(!list_empty(&fs_info->hashers)) {
1904 struct btrfs_hasher *hasher;
1905 hasher = list_entry(fs_info->hashers.next, struct btrfs_hasher,
1906 hashers);
1907 list_del(&hasher->hashers);
1908 crypto_free_hash(&fs_info->hash_tfm);
1909 kfree(hasher);
1910 }
1911#endif
1912 btrfs_close_devices(fs_info->fs_devices);
1913 btrfs_mapping_tree_free(&fs_info->mapping_tree);
1914
1915 bdi_destroy(&fs_info->bdi);
1916
1917 kfree(fs_info->extent_root);
1918 kfree(fs_info->tree_root);
1919 kfree(fs_info->chunk_root);
1920 kfree(fs_info->dev_root);
1921 return 0;
1922}
1923
1924int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1925{
1926 int ret;
1927 struct inode *btree_inode = buf->first_page->mapping->host;
1928
1929 ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
1930 if (!ret)
1931 return ret;
1932
1933 ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
1934 parent_transid);
1935 return !ret;
1936}
1937
1938int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
1939{
1940 struct inode *btree_inode = buf->first_page->mapping->host;
1941 return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
1942 buf);
1943}
1944
1945void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
1946{
1947 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
1948 u64 transid = btrfs_header_generation(buf);
1949 struct inode *btree_inode = root->fs_info->btree_inode;
1950
1951 WARN_ON(!btrfs_tree_locked(buf));
1952 if (transid != root->fs_info->generation) {
1953 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
1954 (unsigned long long)buf->start,
1955 transid, root->fs_info->generation);
1956 WARN_ON(1);
1957 }
1958 set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree, buf);
1959}
1960
1961void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
1962{
1963 /*
1964 * looks as though older kernels can get into trouble with
1965 * this code, they end up stuck in balance_dirty_pages forever
1966 */
1967 struct extent_io_tree *tree;
1968 u64 num_dirty;
1969 u64 start = 0;
1970 unsigned long thresh = 96 * 1024 * 1024;
1971 tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
1972
1973 if (current_is_pdflush() || current->flags & PF_MEMALLOC)
1974 return;
1975
1976 num_dirty = count_range_bits(tree, &start, (u64)-1,
1977 thresh, EXTENT_DIRTY);
1978 if (num_dirty > thresh) {
1979 balance_dirty_pages_ratelimited_nr(
1980 root->fs_info->btree_inode->i_mapping, 1);
1981 }
1982 return;
1983}
1984
1985int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
1986{
1987 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
1988 int ret;
1989 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1990 if (ret == 0) {
1991 buf->flags |= EXTENT_UPTODATE;
1992 }
1993 return ret;
1994}
1995
1996int btree_lock_page_hook(struct page *page)
1997{
1998 struct inode *inode = page->mapping->host;
1999 struct btrfs_root *root = BTRFS_I(inode)->root;
2000 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2001 struct extent_buffer *eb;
2002 unsigned long len;
2003 u64 bytenr = page_offset(page);
2004
2005 if (page->private == EXTENT_PAGE_PRIVATE)
2006 goto out;
2007
2008 len = page->private >> 2;
2009 eb = find_extent_buffer(io_tree, bytenr, len, GFP_NOFS);
2010 if (!eb)
2011 goto out;
2012
2013 btrfs_tree_lock(eb);
2014 spin_lock(&root->fs_info->hash_lock);
2015 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
2016 spin_unlock(&root->fs_info->hash_lock);
2017 btrfs_tree_unlock(eb);
2018 free_extent_buffer(eb);
2019out:
2020 lock_page(page);
2021 return 0;
2022}
2023
2024static struct extent_io_ops btree_extent_io_ops = {
2025 .write_cache_pages_lock_hook = btree_lock_page_hook,
2026 .readpage_end_io_hook = btree_readpage_end_io_hook,
2027 .submit_bio_hook = btree_submit_bio_hook,
2028 /* note we're sharing with inode.c for the merge bio hook */
2029 .merge_bio_hook = btrfs_merge_bio_hook,
2030};
Linux 6.x block layer and io_uring tree(s)