2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
24 #include <linux/pagemap.h>
25 #include <linux/highmem.h>
26 #include <linux/time.h>
27 #include <linux/init.h>
28 #include <linux/string.h>
29 #include <linux/backing-dev.h>
30 #include <linux/mpage.h>
31 #include <linux/swap.h>
32 #include <linux/writeback.h>
33 #include <linux/statfs.h>
34 #include <linux/compat.h>
35 #include <linux/aio.h>
36 #include <linux/bit_spinlock.h>
37 #include <linux/xattr.h>
38 #include <linux/posix_acl.h>
39 #include <linux/falloc.h>
40 #include <linux/slab.h>
41 #include <linux/ratelimit.h>
42 #include <linux/mount.h>
43 #include <linux/btrfs.h>
44 #include <linux/blkdev.h>
45 #include <linux/posix_acl_xattr.h>
48 #include "transaction.h"
49 #include "btrfs_inode.h"
50 #include "print-tree.h"
51 #include "ordered-data.h"
55 #include "compression.h"
57 #include "free-space-cache.h"
58 #include "inode-map.h"
62 struct btrfs_iget_args {
64 struct btrfs_root *root;
67 static const struct inode_operations btrfs_dir_inode_operations;
68 static const struct inode_operations btrfs_symlink_inode_operations;
69 static const struct inode_operations btrfs_dir_ro_inode_operations;
70 static const struct inode_operations btrfs_special_inode_operations;
71 static const struct inode_operations btrfs_file_inode_operations;
72 static const struct address_space_operations btrfs_aops;
73 static const struct address_space_operations btrfs_symlink_aops;
74 static const struct file_operations btrfs_dir_file_operations;
75 static struct extent_io_ops btrfs_extent_io_ops;
77 static struct kmem_cache *btrfs_inode_cachep;
78 static struct kmem_cache *btrfs_delalloc_work_cachep;
79 struct kmem_cache *btrfs_trans_handle_cachep;
80 struct kmem_cache *btrfs_transaction_cachep;
81 struct kmem_cache *btrfs_path_cachep;
82 struct kmem_cache *btrfs_free_space_cachep;
85 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
86 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
87 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
88 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
89 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
90 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
91 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
92 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
95 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
96 static int btrfs_truncate(struct inode *inode);
97 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
98 static noinline int cow_file_range(struct inode *inode,
99 struct page *locked_page,
100 u64 start, u64 end, int *page_started,
101 unsigned long *nr_written, int unlock);
102 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
103 u64 len, u64 orig_start,
104 u64 block_start, u64 block_len,
105 u64 orig_block_len, u64 ram_bytes,
108 static int btrfs_dirty_inode(struct inode *inode);
110 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
111 struct inode *inode, struct inode *dir,
112 const struct qstr *qstr)
116 err = btrfs_init_acl(trans, inode, dir);
118 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
123 * this does all the hard work for inserting an inline extent into
124 * the btree. The caller should have done a btrfs_drop_extents so that
125 * no overlapping inline items exist in the btree
127 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
128 struct btrfs_root *root, struct inode *inode,
129 u64 start, size_t size, size_t compressed_size,
131 struct page **compressed_pages)
133 struct btrfs_key key;
134 struct btrfs_path *path;
135 struct extent_buffer *leaf;
136 struct page *page = NULL;
139 struct btrfs_file_extent_item *ei;
142 size_t cur_size = size;
144 unsigned long offset;
146 if (compressed_size && compressed_pages)
147 cur_size = compressed_size;
149 path = btrfs_alloc_path();
153 path->leave_spinning = 1;
155 key.objectid = btrfs_ino(inode);
157 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
158 datasize = btrfs_file_extent_calc_inline_size(cur_size);
160 inode_add_bytes(inode, size);
161 ret = btrfs_insert_empty_item(trans, root, path, &key,
167 leaf = path->nodes[0];
168 ei = btrfs_item_ptr(leaf, path->slots[0],
169 struct btrfs_file_extent_item);
170 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
171 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
172 btrfs_set_file_extent_encryption(leaf, ei, 0);
173 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
174 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
175 ptr = btrfs_file_extent_inline_start(ei);
177 if (compress_type != BTRFS_COMPRESS_NONE) {
180 while (compressed_size > 0) {
181 cpage = compressed_pages[i];
182 cur_size = min_t(unsigned long, compressed_size,
185 kaddr = kmap_atomic(cpage);
186 write_extent_buffer(leaf, kaddr, ptr, cur_size);
187 kunmap_atomic(kaddr);
191 compressed_size -= cur_size;
193 btrfs_set_file_extent_compression(leaf, ei,
196 page = find_get_page(inode->i_mapping,
197 start >> PAGE_CACHE_SHIFT);
198 btrfs_set_file_extent_compression(leaf, ei, 0);
199 kaddr = kmap_atomic(page);
200 offset = start & (PAGE_CACHE_SIZE - 1);
201 write_extent_buffer(leaf, kaddr + offset, ptr, size);
202 kunmap_atomic(kaddr);
203 page_cache_release(page);
205 btrfs_mark_buffer_dirty(leaf);
206 btrfs_free_path(path);
209 * we're an inline extent, so nobody can
210 * extend the file past i_size without locking
211 * a page we already have locked.
213 * We must do any isize and inode updates
214 * before we unlock the pages. Otherwise we
215 * could end up racing with unlink.
217 BTRFS_I(inode)->disk_i_size = inode->i_size;
218 ret = btrfs_update_inode(trans, root, inode);
222 btrfs_free_path(path);
228 * conditionally insert an inline extent into the file. This
229 * does the checks required to make sure the data is small enough
230 * to fit as an inline extent.
232 static noinline int cow_file_range_inline(struct btrfs_root *root,
233 struct inode *inode, u64 start,
234 u64 end, size_t compressed_size,
236 struct page **compressed_pages)
238 struct btrfs_trans_handle *trans;
239 u64 isize = i_size_read(inode);
240 u64 actual_end = min(end + 1, isize);
241 u64 inline_len = actual_end - start;
242 u64 aligned_end = ALIGN(end, root->sectorsize);
243 u64 data_len = inline_len;
247 data_len = compressed_size;
250 actual_end >= PAGE_CACHE_SIZE ||
251 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
253 (actual_end & (root->sectorsize - 1)) == 0) ||
255 data_len > root->fs_info->max_inline) {
259 trans = btrfs_join_transaction(root);
261 return PTR_ERR(trans);
262 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
264 ret = btrfs_drop_extents(trans, root, inode, start, aligned_end, 1);
266 btrfs_abort_transaction(trans, root, ret);
270 if (isize > actual_end)
271 inline_len = min_t(u64, isize, actual_end);
272 ret = insert_inline_extent(trans, root, inode, start,
273 inline_len, compressed_size,
274 compress_type, compressed_pages);
275 if (ret && ret != -ENOSPC) {
276 btrfs_abort_transaction(trans, root, ret);
278 } else if (ret == -ENOSPC) {
283 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
284 btrfs_delalloc_release_metadata(inode, end + 1 - start);
285 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
287 btrfs_end_transaction(trans, root);
291 struct async_extent {
296 unsigned long nr_pages;
298 struct list_head list;
303 struct btrfs_root *root;
304 struct page *locked_page;
307 struct list_head extents;
308 struct btrfs_work work;
311 static noinline int add_async_extent(struct async_cow *cow,
312 u64 start, u64 ram_size,
315 unsigned long nr_pages,
318 struct async_extent *async_extent;
320 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
321 BUG_ON(!async_extent); /* -ENOMEM */
322 async_extent->start = start;
323 async_extent->ram_size = ram_size;
324 async_extent->compressed_size = compressed_size;
325 async_extent->pages = pages;
326 async_extent->nr_pages = nr_pages;
327 async_extent->compress_type = compress_type;
328 list_add_tail(&async_extent->list, &cow->extents);
333 * we create compressed extents in two phases. The first
334 * phase compresses a range of pages that have already been
335 * locked (both pages and state bits are locked).
337 * This is done inside an ordered work queue, and the compression
338 * is spread across many cpus. The actual IO submission is step
339 * two, and the ordered work queue takes care of making sure that
340 * happens in the same order things were put onto the queue by
341 * writepages and friends.
343 * If this code finds it can't get good compression, it puts an
344 * entry onto the work queue to write the uncompressed bytes. This
345 * makes sure that both compressed inodes and uncompressed inodes
346 * are written in the same order that the flusher thread sent them
349 static noinline int compress_file_range(struct inode *inode,
350 struct page *locked_page,
352 struct async_cow *async_cow,
355 struct btrfs_root *root = BTRFS_I(inode)->root;
357 u64 blocksize = root->sectorsize;
359 u64 isize = i_size_read(inode);
361 struct page **pages = NULL;
362 unsigned long nr_pages;
363 unsigned long nr_pages_ret = 0;
364 unsigned long total_compressed = 0;
365 unsigned long total_in = 0;
366 unsigned long max_compressed = 128 * 1024;
367 unsigned long max_uncompressed = 128 * 1024;
370 int compress_type = root->fs_info->compress_type;
373 /* if this is a small write inside eof, kick off a defrag */
374 if ((end - start + 1) < 16 * 1024 &&
375 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
376 btrfs_add_inode_defrag(NULL, inode);
378 actual_end = min_t(u64, isize, end + 1);
381 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
382 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
385 * we don't want to send crud past the end of i_size through
386 * compression, that's just a waste of CPU time. So, if the
387 * end of the file is before the start of our current
388 * requested range of bytes, we bail out to the uncompressed
389 * cleanup code that can deal with all of this.
391 * It isn't really the fastest way to fix things, but this is a
392 * very uncommon corner.
394 if (actual_end <= start)
395 goto cleanup_and_bail_uncompressed;
397 total_compressed = actual_end - start;
399 /* we want to make sure that amount of ram required to uncompress
400 * an extent is reasonable, so we limit the total size in ram
401 * of a compressed extent to 128k. This is a crucial number
402 * because it also controls how easily we can spread reads across
403 * cpus for decompression.
405 * We also want to make sure the amount of IO required to do
406 * a random read is reasonably small, so we limit the size of
407 * a compressed extent to 128k.
409 total_compressed = min(total_compressed, max_uncompressed);
410 num_bytes = ALIGN(end - start + 1, blocksize);
411 num_bytes = max(blocksize, num_bytes);
416 * we do compression for mount -o compress and when the
417 * inode has not been flagged as nocompress. This flag can
418 * change at any time if we discover bad compression ratios.
420 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
421 (btrfs_test_opt(root, COMPRESS) ||
422 (BTRFS_I(inode)->force_compress) ||
423 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
425 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
427 /* just bail out to the uncompressed code */
431 if (BTRFS_I(inode)->force_compress)
432 compress_type = BTRFS_I(inode)->force_compress;
435 * we need to call clear_page_dirty_for_io on each
436 * page in the range. Otherwise applications with the file
437 * mmap'd can wander in and change the page contents while
438 * we are compressing them.
440 * If the compression fails for any reason, we set the pages
441 * dirty again later on.
443 extent_range_clear_dirty_for_io(inode, start, end);
445 ret = btrfs_compress_pages(compress_type,
446 inode->i_mapping, start,
447 total_compressed, pages,
448 nr_pages, &nr_pages_ret,
454 unsigned long offset = total_compressed &
455 (PAGE_CACHE_SIZE - 1);
456 struct page *page = pages[nr_pages_ret - 1];
459 /* zero the tail end of the last page, we might be
460 * sending it down to disk
463 kaddr = kmap_atomic(page);
464 memset(kaddr + offset, 0,
465 PAGE_CACHE_SIZE - offset);
466 kunmap_atomic(kaddr);
473 /* lets try to make an inline extent */
474 if (ret || total_in < (actual_end - start)) {
475 /* we didn't compress the entire range, try
476 * to make an uncompressed inline extent.
478 ret = cow_file_range_inline(root, inode, start, end,
481 /* try making a compressed inline extent */
482 ret = cow_file_range_inline(root, inode, start, end,
484 compress_type, pages);
487 unsigned long clear_flags = EXTENT_DELALLOC |
489 clear_flags |= (ret < 0) ? EXTENT_DO_ACCOUNTING : 0;
492 * inline extent creation worked or returned error,
493 * we don't need to create any more async work items.
494 * Unlock and free up our temp pages.
496 extent_clear_unlock_delalloc(inode, start, end, NULL,
497 clear_flags, PAGE_UNLOCK |
507 * we aren't doing an inline extent round the compressed size
508 * up to a block size boundary so the allocator does sane
511 total_compressed = ALIGN(total_compressed, blocksize);
514 * one last check to make sure the compression is really a
515 * win, compare the page count read with the blocks on disk
517 total_in = ALIGN(total_in, PAGE_CACHE_SIZE);
518 if (total_compressed >= total_in) {
521 num_bytes = total_in;
524 if (!will_compress && pages) {
526 * the compression code ran but failed to make things smaller,
527 * free any pages it allocated and our page pointer array
529 for (i = 0; i < nr_pages_ret; i++) {
530 WARN_ON(pages[i]->mapping);
531 page_cache_release(pages[i]);
535 total_compressed = 0;
538 /* flag the file so we don't compress in the future */
539 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
540 !(BTRFS_I(inode)->force_compress)) {
541 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
547 /* the async work queues will take care of doing actual
548 * allocation on disk for these compressed pages,
549 * and will submit them to the elevator.
551 add_async_extent(async_cow, start, num_bytes,
552 total_compressed, pages, nr_pages_ret,
555 if (start + num_bytes < end) {
562 cleanup_and_bail_uncompressed:
564 * No compression, but we still need to write the pages in
565 * the file we've been given so far. redirty the locked
566 * page if it corresponds to our extent and set things up
567 * for the async work queue to run cow_file_range to do
568 * the normal delalloc dance
570 if (page_offset(locked_page) >= start &&
571 page_offset(locked_page) <= end) {
572 __set_page_dirty_nobuffers(locked_page);
573 /* unlocked later on in the async handlers */
576 extent_range_redirty_for_io(inode, start, end);
577 add_async_extent(async_cow, start, end - start + 1,
578 0, NULL, 0, BTRFS_COMPRESS_NONE);
586 for (i = 0; i < nr_pages_ret; i++) {
587 WARN_ON(pages[i]->mapping);
588 page_cache_release(pages[i]);
596 * phase two of compressed writeback. This is the ordered portion
597 * of the code, which only gets called in the order the work was
598 * queued. We walk all the async extents created by compress_file_range
599 * and send them down to the disk.
601 static noinline int submit_compressed_extents(struct inode *inode,
602 struct async_cow *async_cow)
604 struct async_extent *async_extent;
606 struct btrfs_key ins;
607 struct extent_map *em;
608 struct btrfs_root *root = BTRFS_I(inode)->root;
609 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
610 struct extent_io_tree *io_tree;
613 if (list_empty(&async_cow->extents))
617 while (!list_empty(&async_cow->extents)) {
618 async_extent = list_entry(async_cow->extents.next,
619 struct async_extent, list);
620 list_del(&async_extent->list);
622 io_tree = &BTRFS_I(inode)->io_tree;
625 /* did the compression code fall back to uncompressed IO? */
626 if (!async_extent->pages) {
627 int page_started = 0;
628 unsigned long nr_written = 0;
630 lock_extent(io_tree, async_extent->start,
631 async_extent->start +
632 async_extent->ram_size - 1);
634 /* allocate blocks */
635 ret = cow_file_range(inode, async_cow->locked_page,
637 async_extent->start +
638 async_extent->ram_size - 1,
639 &page_started, &nr_written, 0);
644 * if page_started, cow_file_range inserted an
645 * inline extent and took care of all the unlocking
646 * and IO for us. Otherwise, we need to submit
647 * all those pages down to the drive.
649 if (!page_started && !ret)
650 extent_write_locked_range(io_tree,
651 inode, async_extent->start,
652 async_extent->start +
653 async_extent->ram_size - 1,
657 unlock_page(async_cow->locked_page);
663 lock_extent(io_tree, async_extent->start,
664 async_extent->start + async_extent->ram_size - 1);
666 ret = btrfs_reserve_extent(root,
667 async_extent->compressed_size,
668 async_extent->compressed_size,
669 0, alloc_hint, &ins, 1);
673 for (i = 0; i < async_extent->nr_pages; i++) {
674 WARN_ON(async_extent->pages[i]->mapping);
675 page_cache_release(async_extent->pages[i]);
677 kfree(async_extent->pages);
678 async_extent->nr_pages = 0;
679 async_extent->pages = NULL;
681 if (ret == -ENOSPC) {
682 unlock_extent(io_tree, async_extent->start,
683 async_extent->start +
684 async_extent->ram_size - 1);
691 * here we're doing allocation and writeback of the
694 btrfs_drop_extent_cache(inode, async_extent->start,
695 async_extent->start +
696 async_extent->ram_size - 1, 0);
698 em = alloc_extent_map();
701 goto out_free_reserve;
703 em->start = async_extent->start;
704 em->len = async_extent->ram_size;
705 em->orig_start = em->start;
706 em->mod_start = em->start;
707 em->mod_len = em->len;
709 em->block_start = ins.objectid;
710 em->block_len = ins.offset;
711 em->orig_block_len = ins.offset;
712 em->ram_bytes = async_extent->ram_size;
713 em->bdev = root->fs_info->fs_devices->latest_bdev;
714 em->compress_type = async_extent->compress_type;
715 set_bit(EXTENT_FLAG_PINNED, &em->flags);
716 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
720 write_lock(&em_tree->lock);
721 ret = add_extent_mapping(em_tree, em, 1);
722 write_unlock(&em_tree->lock);
723 if (ret != -EEXIST) {
727 btrfs_drop_extent_cache(inode, async_extent->start,
728 async_extent->start +
729 async_extent->ram_size - 1, 0);
733 goto out_free_reserve;
735 ret = btrfs_add_ordered_extent_compress(inode,
738 async_extent->ram_size,
740 BTRFS_ORDERED_COMPRESSED,
741 async_extent->compress_type);
743 goto out_free_reserve;
746 * clear dirty, set writeback and unlock the pages.
748 extent_clear_unlock_delalloc(inode, async_extent->start,
749 async_extent->start +
750 async_extent->ram_size - 1,
751 NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
752 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
754 ret = btrfs_submit_compressed_write(inode,
756 async_extent->ram_size,
758 ins.offset, async_extent->pages,
759 async_extent->nr_pages);
760 alloc_hint = ins.objectid + ins.offset;
770 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
772 extent_clear_unlock_delalloc(inode, async_extent->start,
773 async_extent->start +
774 async_extent->ram_size - 1,
775 NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
776 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING,
777 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
778 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK);
783 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
786 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
787 struct extent_map *em;
790 read_lock(&em_tree->lock);
791 em = search_extent_mapping(em_tree, start, num_bytes);
794 * if block start isn't an actual block number then find the
795 * first block in this inode and use that as a hint. If that
796 * block is also bogus then just don't worry about it.
798 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
800 em = search_extent_mapping(em_tree, 0, 0);
801 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
802 alloc_hint = em->block_start;
806 alloc_hint = em->block_start;
810 read_unlock(&em_tree->lock);
816 * when extent_io.c finds a delayed allocation range in the file,
817 * the call backs end up in this code. The basic idea is to
818 * allocate extents on disk for the range, and create ordered data structs
819 * in ram to track those extents.
821 * locked_page is the page that writepage had locked already. We use
822 * it to make sure we don't do extra locks or unlocks.
824 * *page_started is set to one if we unlock locked_page and do everything
825 * required to start IO on it. It may be clean and already done with
828 static noinline int cow_file_range(struct inode *inode,
829 struct page *locked_page,
830 u64 start, u64 end, int *page_started,
831 unsigned long *nr_written,
834 struct btrfs_root *root = BTRFS_I(inode)->root;
837 unsigned long ram_size;
840 u64 blocksize = root->sectorsize;
841 struct btrfs_key ins;
842 struct extent_map *em;
843 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
846 if (btrfs_is_free_space_inode(inode)) {
851 num_bytes = ALIGN(end - start + 1, blocksize);
852 num_bytes = max(blocksize, num_bytes);
853 disk_num_bytes = num_bytes;
855 /* if this is a small write inside eof, kick off defrag */
856 if (num_bytes < 64 * 1024 &&
857 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
858 btrfs_add_inode_defrag(NULL, inode);
861 /* lets try to make an inline extent */
862 ret = cow_file_range_inline(root, inode, start, end, 0, 0,
865 extent_clear_unlock_delalloc(inode, start, end, NULL,
866 EXTENT_LOCKED | EXTENT_DELALLOC |
867 EXTENT_DEFRAG, PAGE_UNLOCK |
868 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
871 *nr_written = *nr_written +
872 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
875 } else if (ret < 0) {
880 BUG_ON(disk_num_bytes >
881 btrfs_super_total_bytes(root->fs_info->super_copy));
883 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
884 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
886 while (disk_num_bytes > 0) {
889 cur_alloc_size = disk_num_bytes;
890 ret = btrfs_reserve_extent(root, cur_alloc_size,
891 root->sectorsize, 0, alloc_hint,
896 em = alloc_extent_map();
902 em->orig_start = em->start;
903 ram_size = ins.offset;
904 em->len = ins.offset;
905 em->mod_start = em->start;
906 em->mod_len = em->len;
908 em->block_start = ins.objectid;
909 em->block_len = ins.offset;
910 em->orig_block_len = ins.offset;
911 em->ram_bytes = ram_size;
912 em->bdev = root->fs_info->fs_devices->latest_bdev;
913 set_bit(EXTENT_FLAG_PINNED, &em->flags);
917 write_lock(&em_tree->lock);
918 ret = add_extent_mapping(em_tree, em, 1);
919 write_unlock(&em_tree->lock);
920 if (ret != -EEXIST) {
924 btrfs_drop_extent_cache(inode, start,
925 start + ram_size - 1, 0);
930 cur_alloc_size = ins.offset;
931 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
932 ram_size, cur_alloc_size, 0);
936 if (root->root_key.objectid ==
937 BTRFS_DATA_RELOC_TREE_OBJECTID) {
938 ret = btrfs_reloc_clone_csums(inode, start,
944 if (disk_num_bytes < cur_alloc_size)
947 /* we're not doing compressed IO, don't unlock the first
948 * page (which the caller expects to stay locked), don't
949 * clear any dirty bits and don't set any writeback bits
951 * Do set the Private2 bit so we know this page was properly
952 * setup for writepage
954 op = unlock ? PAGE_UNLOCK : 0;
955 op |= PAGE_SET_PRIVATE2;
957 extent_clear_unlock_delalloc(inode, start,
958 start + ram_size - 1, locked_page,
959 EXTENT_LOCKED | EXTENT_DELALLOC,
961 disk_num_bytes -= cur_alloc_size;
962 num_bytes -= cur_alloc_size;
963 alloc_hint = ins.objectid + ins.offset;
964 start += cur_alloc_size;
970 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
972 extent_clear_unlock_delalloc(inode, start, end, locked_page,
973 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
974 EXTENT_DELALLOC | EXTENT_DEFRAG,
975 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
976 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK);
981 * work queue call back to started compression on a file and pages
983 static noinline void async_cow_start(struct btrfs_work *work)
985 struct async_cow *async_cow;
987 async_cow = container_of(work, struct async_cow, work);
989 compress_file_range(async_cow->inode, async_cow->locked_page,
990 async_cow->start, async_cow->end, async_cow,
992 if (num_added == 0) {
993 btrfs_add_delayed_iput(async_cow->inode);
994 async_cow->inode = NULL;
999 * work queue call back to submit previously compressed pages
1001 static noinline void async_cow_submit(struct btrfs_work *work)
1003 struct async_cow *async_cow;
1004 struct btrfs_root *root;
1005 unsigned long nr_pages;
1007 async_cow = container_of(work, struct async_cow, work);
1009 root = async_cow->root;
1010 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
1013 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
1015 waitqueue_active(&root->fs_info->async_submit_wait))
1016 wake_up(&root->fs_info->async_submit_wait);
1018 if (async_cow->inode)
1019 submit_compressed_extents(async_cow->inode, async_cow);
1022 static noinline void async_cow_free(struct btrfs_work *work)
1024 struct async_cow *async_cow;
1025 async_cow = container_of(work, struct async_cow, work);
1026 if (async_cow->inode)
1027 btrfs_add_delayed_iput(async_cow->inode);
1031 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1032 u64 start, u64 end, int *page_started,
1033 unsigned long *nr_written)
1035 struct async_cow *async_cow;
1036 struct btrfs_root *root = BTRFS_I(inode)->root;
1037 unsigned long nr_pages;
1039 int limit = 10 * 1024 * 1024;
1041 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1042 1, 0, NULL, GFP_NOFS);
1043 while (start < end) {
1044 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1045 BUG_ON(!async_cow); /* -ENOMEM */
1046 async_cow->inode = igrab(inode);
1047 async_cow->root = root;
1048 async_cow->locked_page = locked_page;
1049 async_cow->start = start;
1051 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
1054 cur_end = min(end, start + 512 * 1024 - 1);
1056 async_cow->end = cur_end;
1057 INIT_LIST_HEAD(&async_cow->extents);
1059 async_cow->work.func = async_cow_start;
1060 async_cow->work.ordered_func = async_cow_submit;
1061 async_cow->work.ordered_free = async_cow_free;
1062 async_cow->work.flags = 0;
1064 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1066 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1068 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1071 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1072 wait_event(root->fs_info->async_submit_wait,
1073 (atomic_read(&root->fs_info->async_delalloc_pages) <
1077 while (atomic_read(&root->fs_info->async_submit_draining) &&
1078 atomic_read(&root->fs_info->async_delalloc_pages)) {
1079 wait_event(root->fs_info->async_submit_wait,
1080 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1084 *nr_written += nr_pages;
1085 start = cur_end + 1;
1091 static noinline int csum_exist_in_range(struct btrfs_root *root,
1092 u64 bytenr, u64 num_bytes)
1095 struct btrfs_ordered_sum *sums;
1098 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1099 bytenr + num_bytes - 1, &list, 0);
1100 if (ret == 0 && list_empty(&list))
1103 while (!list_empty(&list)) {
1104 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1105 list_del(&sums->list);
1112 * when nowcow writeback call back. This checks for snapshots or COW copies
1113 * of the extents that exist in the file, and COWs the file as required.
1115 * If no cow copies or snapshots exist, we write directly to the existing
1118 static noinline int run_delalloc_nocow(struct inode *inode,
1119 struct page *locked_page,
1120 u64 start, u64 end, int *page_started, int force,
1121 unsigned long *nr_written)
1123 struct btrfs_root *root = BTRFS_I(inode)->root;
1124 struct btrfs_trans_handle *trans;
1125 struct extent_buffer *leaf;
1126 struct btrfs_path *path;
1127 struct btrfs_file_extent_item *fi;
1128 struct btrfs_key found_key;
1143 u64 ino = btrfs_ino(inode);
1145 path = btrfs_alloc_path();
1147 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1148 EXTENT_LOCKED | EXTENT_DELALLOC |
1149 EXTENT_DO_ACCOUNTING |
1150 EXTENT_DEFRAG, PAGE_UNLOCK |
1152 PAGE_SET_WRITEBACK |
1153 PAGE_END_WRITEBACK);
1157 nolock = btrfs_is_free_space_inode(inode);
1160 trans = btrfs_join_transaction_nolock(root);
1162 trans = btrfs_join_transaction(root);
1164 if (IS_ERR(trans)) {
1165 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1166 EXTENT_LOCKED | EXTENT_DELALLOC |
1167 EXTENT_DO_ACCOUNTING |
1168 EXTENT_DEFRAG, PAGE_UNLOCK |
1170 PAGE_SET_WRITEBACK |
1171 PAGE_END_WRITEBACK);
1172 btrfs_free_path(path);
1173 return PTR_ERR(trans);
1176 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1178 cow_start = (u64)-1;
1181 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1185 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1186 leaf = path->nodes[0];
1187 btrfs_item_key_to_cpu(leaf, &found_key,
1188 path->slots[0] - 1);
1189 if (found_key.objectid == ino &&
1190 found_key.type == BTRFS_EXTENT_DATA_KEY)
1195 leaf = path->nodes[0];
1196 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1197 ret = btrfs_next_leaf(root, path);
1202 leaf = path->nodes[0];
1208 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1210 if (found_key.objectid > ino ||
1211 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1212 found_key.offset > end)
1215 if (found_key.offset > cur_offset) {
1216 extent_end = found_key.offset;
1221 fi = btrfs_item_ptr(leaf, path->slots[0],
1222 struct btrfs_file_extent_item);
1223 extent_type = btrfs_file_extent_type(leaf, fi);
1225 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1226 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1227 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1228 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1229 extent_offset = btrfs_file_extent_offset(leaf, fi);
1230 extent_end = found_key.offset +
1231 btrfs_file_extent_num_bytes(leaf, fi);
1233 btrfs_file_extent_disk_num_bytes(leaf, fi);
1234 if (extent_end <= start) {
1238 if (disk_bytenr == 0)
1240 if (btrfs_file_extent_compression(leaf, fi) ||
1241 btrfs_file_extent_encryption(leaf, fi) ||
1242 btrfs_file_extent_other_encoding(leaf, fi))
1244 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1246 if (btrfs_extent_readonly(root, disk_bytenr))
1248 if (btrfs_cross_ref_exist(trans, root, ino,
1250 extent_offset, disk_bytenr))
1252 disk_bytenr += extent_offset;
1253 disk_bytenr += cur_offset - found_key.offset;
1254 num_bytes = min(end + 1, extent_end) - cur_offset;
1256 * force cow if csum exists in the range.
1257 * this ensure that csum for a given extent are
1258 * either valid or do not exist.
1260 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1263 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1264 extent_end = found_key.offset +
1265 btrfs_file_extent_inline_len(leaf, fi);
1266 extent_end = ALIGN(extent_end, root->sectorsize);
1271 if (extent_end <= start) {
1276 if (cow_start == (u64)-1)
1277 cow_start = cur_offset;
1278 cur_offset = extent_end;
1279 if (cur_offset > end)
1285 btrfs_release_path(path);
1286 if (cow_start != (u64)-1) {
1287 ret = cow_file_range(inode, locked_page,
1288 cow_start, found_key.offset - 1,
1289 page_started, nr_written, 1);
1292 cow_start = (u64)-1;
1295 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1296 struct extent_map *em;
1297 struct extent_map_tree *em_tree;
1298 em_tree = &BTRFS_I(inode)->extent_tree;
1299 em = alloc_extent_map();
1300 BUG_ON(!em); /* -ENOMEM */
1301 em->start = cur_offset;
1302 em->orig_start = found_key.offset - extent_offset;
1303 em->len = num_bytes;
1304 em->block_len = num_bytes;
1305 em->block_start = disk_bytenr;
1306 em->orig_block_len = disk_num_bytes;
1307 em->ram_bytes = ram_bytes;
1308 em->bdev = root->fs_info->fs_devices->latest_bdev;
1309 em->mod_start = em->start;
1310 em->mod_len = em->len;
1311 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1312 set_bit(EXTENT_FLAG_FILLING, &em->flags);
1313 em->generation = -1;
1315 write_lock(&em_tree->lock);
1316 ret = add_extent_mapping(em_tree, em, 1);
1317 write_unlock(&em_tree->lock);
1318 if (ret != -EEXIST) {
1319 free_extent_map(em);
1322 btrfs_drop_extent_cache(inode, em->start,
1323 em->start + em->len - 1, 0);
1325 type = BTRFS_ORDERED_PREALLOC;
1327 type = BTRFS_ORDERED_NOCOW;
1330 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1331 num_bytes, num_bytes, type);
1332 BUG_ON(ret); /* -ENOMEM */
1334 if (root->root_key.objectid ==
1335 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1336 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1342 extent_clear_unlock_delalloc(inode, cur_offset,
1343 cur_offset + num_bytes - 1,
1344 locked_page, EXTENT_LOCKED |
1345 EXTENT_DELALLOC, PAGE_UNLOCK |
1347 cur_offset = extent_end;
1348 if (cur_offset > end)
1351 btrfs_release_path(path);
1353 if (cur_offset <= end && cow_start == (u64)-1) {
1354 cow_start = cur_offset;
1358 if (cow_start != (u64)-1) {
1359 ret = cow_file_range(inode, locked_page, cow_start, end,
1360 page_started, nr_written, 1);
1366 err = btrfs_end_transaction(trans, root);
1370 if (ret && cur_offset < end)
1371 extent_clear_unlock_delalloc(inode, cur_offset, end,
1372 locked_page, EXTENT_LOCKED |
1373 EXTENT_DELALLOC | EXTENT_DEFRAG |
1374 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1376 PAGE_SET_WRITEBACK |
1377 PAGE_END_WRITEBACK);
1378 btrfs_free_path(path);
1383 * extent_io.c call back to do delayed allocation processing
1385 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1386 u64 start, u64 end, int *page_started,
1387 unsigned long *nr_written)
1390 struct btrfs_root *root = BTRFS_I(inode)->root;
1392 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
1393 ret = run_delalloc_nocow(inode, locked_page, start, end,
1394 page_started, 1, nr_written);
1395 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
1396 ret = run_delalloc_nocow(inode, locked_page, start, end,
1397 page_started, 0, nr_written);
1398 } else if (!btrfs_test_opt(root, COMPRESS) &&
1399 !(BTRFS_I(inode)->force_compress) &&
1400 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
1401 ret = cow_file_range(inode, locked_page, start, end,
1402 page_started, nr_written, 1);
1404 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1405 &BTRFS_I(inode)->runtime_flags);
1406 ret = cow_file_range_async(inode, locked_page, start, end,
1407 page_started, nr_written);
1412 static void btrfs_split_extent_hook(struct inode *inode,
1413 struct extent_state *orig, u64 split)
1415 /* not delalloc, ignore it */
1416 if (!(orig->state & EXTENT_DELALLOC))
1419 spin_lock(&BTRFS_I(inode)->lock);
1420 BTRFS_I(inode)->outstanding_extents++;
1421 spin_unlock(&BTRFS_I(inode)->lock);
1425 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1426 * extents so we can keep track of new extents that are just merged onto old
1427 * extents, such as when we are doing sequential writes, so we can properly
1428 * account for the metadata space we'll need.
1430 static void btrfs_merge_extent_hook(struct inode *inode,
1431 struct extent_state *new,
1432 struct extent_state *other)
1434 /* not delalloc, ignore it */
1435 if (!(other->state & EXTENT_DELALLOC))
1438 spin_lock(&BTRFS_I(inode)->lock);
1439 BTRFS_I(inode)->outstanding_extents--;
1440 spin_unlock(&BTRFS_I(inode)->lock);
1443 static void btrfs_add_delalloc_inodes(struct btrfs_root *root,
1444 struct inode *inode)
1446 spin_lock(&root->delalloc_lock);
1447 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1448 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1449 &root->delalloc_inodes);
1450 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1451 &BTRFS_I(inode)->runtime_flags);
1452 root->nr_delalloc_inodes++;
1453 if (root->nr_delalloc_inodes == 1) {
1454 spin_lock(&root->fs_info->delalloc_root_lock);
1455 BUG_ON(!list_empty(&root->delalloc_root));
1456 list_add_tail(&root->delalloc_root,
1457 &root->fs_info->delalloc_roots);
1458 spin_unlock(&root->fs_info->delalloc_root_lock);
1461 spin_unlock(&root->delalloc_lock);
1464 static void btrfs_del_delalloc_inode(struct btrfs_root *root,
1465 struct inode *inode)
1467 spin_lock(&root->delalloc_lock);
1468 if (!list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1469 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1470 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1471 &BTRFS_I(inode)->runtime_flags);
1472 root->nr_delalloc_inodes--;
1473 if (!root->nr_delalloc_inodes) {
1474 spin_lock(&root->fs_info->delalloc_root_lock);
1475 BUG_ON(list_empty(&root->delalloc_root));
1476 list_del_init(&root->delalloc_root);
1477 spin_unlock(&root->fs_info->delalloc_root_lock);
1480 spin_unlock(&root->delalloc_lock);
1484 * extent_io.c set_bit_hook, used to track delayed allocation
1485 * bytes in this file, and to maintain the list of inodes that
1486 * have pending delalloc work to be done.
1488 static void btrfs_set_bit_hook(struct inode *inode,
1489 struct extent_state *state, unsigned long *bits)
1493 * set_bit and clear bit hooks normally require _irqsave/restore
1494 * but in this case, we are only testing for the DELALLOC
1495 * bit, which is only set or cleared with irqs on
1497 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1498 struct btrfs_root *root = BTRFS_I(inode)->root;
1499 u64 len = state->end + 1 - state->start;
1500 bool do_list = !btrfs_is_free_space_inode(inode);
1502 if (*bits & EXTENT_FIRST_DELALLOC) {
1503 *bits &= ~EXTENT_FIRST_DELALLOC;
1505 spin_lock(&BTRFS_I(inode)->lock);
1506 BTRFS_I(inode)->outstanding_extents++;
1507 spin_unlock(&BTRFS_I(inode)->lock);
1510 __percpu_counter_add(&root->fs_info->delalloc_bytes, len,
1511 root->fs_info->delalloc_batch);
1512 spin_lock(&BTRFS_I(inode)->lock);
1513 BTRFS_I(inode)->delalloc_bytes += len;
1514 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1515 &BTRFS_I(inode)->runtime_flags))
1516 btrfs_add_delalloc_inodes(root, inode);
1517 spin_unlock(&BTRFS_I(inode)->lock);
1522 * extent_io.c clear_bit_hook, see set_bit_hook for why
1524 static void btrfs_clear_bit_hook(struct inode *inode,
1525 struct extent_state *state,
1526 unsigned long *bits)
1529 * set_bit and clear bit hooks normally require _irqsave/restore
1530 * but in this case, we are only testing for the DELALLOC
1531 * bit, which is only set or cleared with irqs on
1533 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1534 struct btrfs_root *root = BTRFS_I(inode)->root;
1535 u64 len = state->end + 1 - state->start;
1536 bool do_list = !btrfs_is_free_space_inode(inode);
1538 if (*bits & EXTENT_FIRST_DELALLOC) {
1539 *bits &= ~EXTENT_FIRST_DELALLOC;
1540 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1541 spin_lock(&BTRFS_I(inode)->lock);
1542 BTRFS_I(inode)->outstanding_extents--;
1543 spin_unlock(&BTRFS_I(inode)->lock);
1547 * We don't reserve metadata space for space cache inodes so we
1548 * don't need to call dellalloc_release_metadata if there is an
1551 if (*bits & EXTENT_DO_ACCOUNTING &&
1552 root != root->fs_info->tree_root)
1553 btrfs_delalloc_release_metadata(inode, len);
1555 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1556 && do_list && !(state->state & EXTENT_NORESERVE))
1557 btrfs_free_reserved_data_space(inode, len);
1559 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len,
1560 root->fs_info->delalloc_batch);
1561 spin_lock(&BTRFS_I(inode)->lock);
1562 BTRFS_I(inode)->delalloc_bytes -= len;
1563 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1564 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1565 &BTRFS_I(inode)->runtime_flags))
1566 btrfs_del_delalloc_inode(root, inode);
1567 spin_unlock(&BTRFS_I(inode)->lock);
1572 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1573 * we don't create bios that span stripes or chunks
1575 int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
1576 size_t size, struct bio *bio,
1577 unsigned long bio_flags)
1579 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1580 u64 logical = (u64)bio->bi_sector << 9;
1585 if (bio_flags & EXTENT_BIO_COMPRESSED)
1588 length = bio->bi_size;
1589 map_length = length;
1590 ret = btrfs_map_block(root->fs_info, rw, logical,
1591 &map_length, NULL, 0);
1592 /* Will always return 0 with map_multi == NULL */
1594 if (map_length < length + size)
1600 * in order to insert checksums into the metadata in large chunks,
1601 * we wait until bio submission time. All the pages in the bio are
1602 * checksummed and sums are attached onto the ordered extent record.
1604 * At IO completion time the cums attached on the ordered extent record
1605 * are inserted into the btree
1607 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1608 struct bio *bio, int mirror_num,
1609 unsigned long bio_flags,
1612 struct btrfs_root *root = BTRFS_I(inode)->root;
1615 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1616 BUG_ON(ret); /* -ENOMEM */
1621 * in order to insert checksums into the metadata in large chunks,
1622 * we wait until bio submission time. All the pages in the bio are
1623 * checksummed and sums are attached onto the ordered extent record.
1625 * At IO completion time the cums attached on the ordered extent record
1626 * are inserted into the btree
1628 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1629 int mirror_num, unsigned long bio_flags,
1632 struct btrfs_root *root = BTRFS_I(inode)->root;
1635 ret = btrfs_map_bio(root, rw, bio, mirror_num, 1);
1637 bio_endio(bio, ret);
1642 * extent_io.c submission hook. This does the right thing for csum calculation
1643 * on write, or reading the csums from the tree before a read
1645 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1646 int mirror_num, unsigned long bio_flags,
1649 struct btrfs_root *root = BTRFS_I(inode)->root;
1653 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
1655 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1657 if (btrfs_is_free_space_inode(inode))
1660 if (!(rw & REQ_WRITE)) {
1661 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata);
1665 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1666 ret = btrfs_submit_compressed_read(inode, bio,
1670 } else if (!skip_sum) {
1671 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1676 } else if (async && !skip_sum) {
1677 /* csum items have already been cloned */
1678 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1680 /* we're doing a write, do the async checksumming */
1681 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1682 inode, rw, bio, mirror_num,
1683 bio_flags, bio_offset,
1684 __btrfs_submit_bio_start,
1685 __btrfs_submit_bio_done);
1687 } else if (!skip_sum) {
1688 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1694 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0);
1698 bio_endio(bio, ret);
1703 * given a list of ordered sums record them in the inode. This happens
1704 * at IO completion time based on sums calculated at bio submission time.
1706 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1707 struct inode *inode, u64 file_offset,
1708 struct list_head *list)
1710 struct btrfs_ordered_sum *sum;
1712 list_for_each_entry(sum, list, list) {
1713 trans->adding_csums = 1;
1714 btrfs_csum_file_blocks(trans,
1715 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1716 trans->adding_csums = 0;
1721 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1722 struct extent_state **cached_state)
1724 WARN_ON((end & (PAGE_CACHE_SIZE - 1)) == 0);
1725 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1726 cached_state, GFP_NOFS);
1729 /* see btrfs_writepage_start_hook for details on why this is required */
1730 struct btrfs_writepage_fixup {
1732 struct btrfs_work work;
1735 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1737 struct btrfs_writepage_fixup *fixup;
1738 struct btrfs_ordered_extent *ordered;
1739 struct extent_state *cached_state = NULL;
1741 struct inode *inode;
1746 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1750 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1751 ClearPageChecked(page);
1755 inode = page->mapping->host;
1756 page_start = page_offset(page);
1757 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1759 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1762 /* already ordered? We're done */
1763 if (PagePrivate2(page))
1766 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1768 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1769 page_end, &cached_state, GFP_NOFS);
1771 btrfs_start_ordered_extent(inode, ordered, 1);
1772 btrfs_put_ordered_extent(ordered);
1776 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
1778 mapping_set_error(page->mapping, ret);
1779 end_extent_writepage(page, ret, page_start, page_end);
1780 ClearPageChecked(page);
1784 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1785 ClearPageChecked(page);
1786 set_page_dirty(page);
1788 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1789 &cached_state, GFP_NOFS);
1792 page_cache_release(page);
1797 * There are a few paths in the higher layers of the kernel that directly
1798 * set the page dirty bit without asking the filesystem if it is a
1799 * good idea. This causes problems because we want to make sure COW
1800 * properly happens and the data=ordered rules are followed.
1802 * In our case any range that doesn't have the ORDERED bit set
1803 * hasn't been properly setup for IO. We kick off an async process
1804 * to fix it up. The async helper will wait for ordered extents, set
1805 * the delalloc bit and make it safe to write the page.
1807 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1809 struct inode *inode = page->mapping->host;
1810 struct btrfs_writepage_fixup *fixup;
1811 struct btrfs_root *root = BTRFS_I(inode)->root;
1813 /* this page is properly in the ordered list */
1814 if (TestClearPagePrivate2(page))
1817 if (PageChecked(page))
1820 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1824 SetPageChecked(page);
1825 page_cache_get(page);
1826 fixup->work.func = btrfs_writepage_fixup_worker;
1828 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1832 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1833 struct inode *inode, u64 file_pos,
1834 u64 disk_bytenr, u64 disk_num_bytes,
1835 u64 num_bytes, u64 ram_bytes,
1836 u8 compression, u8 encryption,
1837 u16 other_encoding, int extent_type)
1839 struct btrfs_root *root = BTRFS_I(inode)->root;
1840 struct btrfs_file_extent_item *fi;
1841 struct btrfs_path *path;
1842 struct extent_buffer *leaf;
1843 struct btrfs_key ins;
1846 path = btrfs_alloc_path();
1850 path->leave_spinning = 1;
1853 * we may be replacing one extent in the tree with another.
1854 * The new extent is pinned in the extent map, and we don't want
1855 * to drop it from the cache until it is completely in the btree.
1857 * So, tell btrfs_drop_extents to leave this extent in the cache.
1858 * the caller is expected to unpin it and allow it to be merged
1861 ret = btrfs_drop_extents(trans, root, inode, file_pos,
1862 file_pos + num_bytes, 0);
1866 ins.objectid = btrfs_ino(inode);
1867 ins.offset = file_pos;
1868 ins.type = BTRFS_EXTENT_DATA_KEY;
1869 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1872 leaf = path->nodes[0];
1873 fi = btrfs_item_ptr(leaf, path->slots[0],
1874 struct btrfs_file_extent_item);
1875 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1876 btrfs_set_file_extent_type(leaf, fi, extent_type);
1877 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1878 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1879 btrfs_set_file_extent_offset(leaf, fi, 0);
1880 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1881 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1882 btrfs_set_file_extent_compression(leaf, fi, compression);
1883 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1884 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1886 btrfs_mark_buffer_dirty(leaf);
1887 btrfs_release_path(path);
1889 inode_add_bytes(inode, num_bytes);
1891 ins.objectid = disk_bytenr;
1892 ins.offset = disk_num_bytes;
1893 ins.type = BTRFS_EXTENT_ITEM_KEY;
1894 ret = btrfs_alloc_reserved_file_extent(trans, root,
1895 root->root_key.objectid,
1896 btrfs_ino(inode), file_pos, &ins);
1898 btrfs_free_path(path);
1903 /* snapshot-aware defrag */
1904 struct sa_defrag_extent_backref {
1905 struct rb_node node;
1906 struct old_sa_defrag_extent *old;
1915 struct old_sa_defrag_extent {
1916 struct list_head list;
1917 struct new_sa_defrag_extent *new;
1926 struct new_sa_defrag_extent {
1927 struct rb_root root;
1928 struct list_head head;
1929 struct btrfs_path *path;
1930 struct inode *inode;
1938 static int backref_comp(struct sa_defrag_extent_backref *b1,
1939 struct sa_defrag_extent_backref *b2)
1941 if (b1->root_id < b2->root_id)
1943 else if (b1->root_id > b2->root_id)
1946 if (b1->inum < b2->inum)
1948 else if (b1->inum > b2->inum)
1951 if (b1->file_pos < b2->file_pos)
1953 else if (b1->file_pos > b2->file_pos)
1957 * [------------------------------] ===> (a range of space)
1958 * |<--->| |<---->| =============> (fs/file tree A)
1959 * |<---------------------------->| ===> (fs/file tree B)
1961 * A range of space can refer to two file extents in one tree while
1962 * refer to only one file extent in another tree.
1964 * So we may process a disk offset more than one time(two extents in A)
1965 * and locate at the same extent(one extent in B), then insert two same
1966 * backrefs(both refer to the extent in B).
1971 static void backref_insert(struct rb_root *root,
1972 struct sa_defrag_extent_backref *backref)
1974 struct rb_node **p = &root->rb_node;
1975 struct rb_node *parent = NULL;
1976 struct sa_defrag_extent_backref *entry;
1981 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
1983 ret = backref_comp(backref, entry);
1987 p = &(*p)->rb_right;
1990 rb_link_node(&backref->node, parent, p);
1991 rb_insert_color(&backref->node, root);
1995 * Note the backref might has changed, and in this case we just return 0.
1997 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2000 struct btrfs_file_extent_item *extent;
2001 struct btrfs_fs_info *fs_info;
2002 struct old_sa_defrag_extent *old = ctx;
2003 struct new_sa_defrag_extent *new = old->new;
2004 struct btrfs_path *path = new->path;
2005 struct btrfs_key key;
2006 struct btrfs_root *root;
2007 struct sa_defrag_extent_backref *backref;
2008 struct extent_buffer *leaf;
2009 struct inode *inode = new->inode;
2015 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2016 inum == btrfs_ino(inode))
2019 key.objectid = root_id;
2020 key.type = BTRFS_ROOT_ITEM_KEY;
2021 key.offset = (u64)-1;
2023 fs_info = BTRFS_I(inode)->root->fs_info;
2024 root = btrfs_read_fs_root_no_name(fs_info, &key);
2026 if (PTR_ERR(root) == -ENOENT)
2029 pr_debug("inum=%llu, offset=%llu, root_id=%llu\n",
2030 inum, offset, root_id);
2031 return PTR_ERR(root);
2034 key.objectid = inum;
2035 key.type = BTRFS_EXTENT_DATA_KEY;
2036 if (offset > (u64)-1 << 32)
2039 key.offset = offset;
2041 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2042 if (WARN_ON(ret < 0))
2049 leaf = path->nodes[0];
2050 slot = path->slots[0];
2052 if (slot >= btrfs_header_nritems(leaf)) {
2053 ret = btrfs_next_leaf(root, path);
2056 } else if (ret > 0) {
2065 btrfs_item_key_to_cpu(leaf, &key, slot);
2067 if (key.objectid > inum)
2070 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2073 extent = btrfs_item_ptr(leaf, slot,
2074 struct btrfs_file_extent_item);
2076 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2080 * 'offset' refers to the exact key.offset,
2081 * NOT the 'offset' field in btrfs_extent_data_ref, ie.
2082 * (key.offset - extent_offset).
2084 if (key.offset != offset)
2087 extent_offset = btrfs_file_extent_offset(leaf, extent);
2088 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2090 if (extent_offset >= old->extent_offset + old->offset +
2091 old->len || extent_offset + num_bytes <=
2092 old->extent_offset + old->offset)
2097 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2103 backref->root_id = root_id;
2104 backref->inum = inum;
2105 backref->file_pos = offset;
2106 backref->num_bytes = num_bytes;
2107 backref->extent_offset = extent_offset;
2108 backref->generation = btrfs_file_extent_generation(leaf, extent);
2110 backref_insert(&new->root, backref);
2113 btrfs_release_path(path);
2118 static noinline bool record_extent_backrefs(struct btrfs_path *path,
2119 struct new_sa_defrag_extent *new)
2121 struct btrfs_fs_info *fs_info = BTRFS_I(new->inode)->root->fs_info;
2122 struct old_sa_defrag_extent *old, *tmp;
2127 list_for_each_entry_safe(old, tmp, &new->head, list) {
2128 ret = iterate_inodes_from_logical(old->bytenr +
2129 old->extent_offset, fs_info,
2130 path, record_one_backref,
2132 if (ret < 0 && ret != -ENOENT)
2135 /* no backref to be processed for this extent */
2137 list_del(&old->list);
2142 if (list_empty(&new->head))
2148 static int relink_is_mergable(struct extent_buffer *leaf,
2149 struct btrfs_file_extent_item *fi,
2150 struct new_sa_defrag_extent *new)
2152 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr)
2155 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2158 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type)
2161 if (btrfs_file_extent_encryption(leaf, fi) ||
2162 btrfs_file_extent_other_encoding(leaf, fi))
2169 * Note the backref might has changed, and in this case we just return 0.
2171 static noinline int relink_extent_backref(struct btrfs_path *path,
2172 struct sa_defrag_extent_backref *prev,
2173 struct sa_defrag_extent_backref *backref)
2175 struct btrfs_file_extent_item *extent;
2176 struct btrfs_file_extent_item *item;
2177 struct btrfs_ordered_extent *ordered;
2178 struct btrfs_trans_handle *trans;
2179 struct btrfs_fs_info *fs_info;
2180 struct btrfs_root *root;
2181 struct btrfs_key key;
2182 struct extent_buffer *leaf;
2183 struct old_sa_defrag_extent *old = backref->old;
2184 struct new_sa_defrag_extent *new = old->new;
2185 struct inode *src_inode = new->inode;
2186 struct inode *inode;
2187 struct extent_state *cached = NULL;
2196 if (prev && prev->root_id == backref->root_id &&
2197 prev->inum == backref->inum &&
2198 prev->file_pos + prev->num_bytes == backref->file_pos)
2201 /* step 1: get root */
2202 key.objectid = backref->root_id;
2203 key.type = BTRFS_ROOT_ITEM_KEY;
2204 key.offset = (u64)-1;
2206 fs_info = BTRFS_I(src_inode)->root->fs_info;
2207 index = srcu_read_lock(&fs_info->subvol_srcu);
2209 root = btrfs_read_fs_root_no_name(fs_info, &key);
2211 srcu_read_unlock(&fs_info->subvol_srcu, index);
2212 if (PTR_ERR(root) == -ENOENT)
2214 return PTR_ERR(root);
2217 /* step 2: get inode */
2218 key.objectid = backref->inum;
2219 key.type = BTRFS_INODE_ITEM_KEY;
2222 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2223 if (IS_ERR(inode)) {
2224 srcu_read_unlock(&fs_info->subvol_srcu, index);
2228 srcu_read_unlock(&fs_info->subvol_srcu, index);
2230 /* step 3: relink backref */
2231 lock_start = backref->file_pos;
2232 lock_end = backref->file_pos + backref->num_bytes - 1;
2233 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2236 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2238 btrfs_put_ordered_extent(ordered);
2242 trans = btrfs_join_transaction(root);
2243 if (IS_ERR(trans)) {
2244 ret = PTR_ERR(trans);
2248 key.objectid = backref->inum;
2249 key.type = BTRFS_EXTENT_DATA_KEY;
2250 key.offset = backref->file_pos;
2252 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2255 } else if (ret > 0) {
2260 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2261 struct btrfs_file_extent_item);
2263 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2264 backref->generation)
2267 btrfs_release_path(path);
2269 start = backref->file_pos;
2270 if (backref->extent_offset < old->extent_offset + old->offset)
2271 start += old->extent_offset + old->offset -
2272 backref->extent_offset;
2274 len = min(backref->extent_offset + backref->num_bytes,
2275 old->extent_offset + old->offset + old->len);
2276 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2278 ret = btrfs_drop_extents(trans, root, inode, start,
2283 key.objectid = btrfs_ino(inode);
2284 key.type = BTRFS_EXTENT_DATA_KEY;
2287 path->leave_spinning = 1;
2289 struct btrfs_file_extent_item *fi;
2291 struct btrfs_key found_key;
2293 ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
2298 leaf = path->nodes[0];
2299 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2301 fi = btrfs_item_ptr(leaf, path->slots[0],
2302 struct btrfs_file_extent_item);
2303 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2305 if (extent_len + found_key.offset == start &&
2306 relink_is_mergable(leaf, fi, new)) {
2307 btrfs_set_file_extent_num_bytes(leaf, fi,
2309 btrfs_mark_buffer_dirty(leaf);
2310 inode_add_bytes(inode, len);
2316 btrfs_release_path(path);
2321 ret = btrfs_insert_empty_item(trans, root, path, &key,
2324 btrfs_abort_transaction(trans, root, ret);
2328 leaf = path->nodes[0];
2329 item = btrfs_item_ptr(leaf, path->slots[0],
2330 struct btrfs_file_extent_item);
2331 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2332 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2333 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2334 btrfs_set_file_extent_num_bytes(leaf, item, len);
2335 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2336 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2337 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2338 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2339 btrfs_set_file_extent_encryption(leaf, item, 0);
2340 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2342 btrfs_mark_buffer_dirty(leaf);
2343 inode_add_bytes(inode, len);
2344 btrfs_release_path(path);
2346 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2348 backref->root_id, backref->inum,
2349 new->file_pos, 0); /* start - extent_offset */
2351 btrfs_abort_transaction(trans, root, ret);
2357 btrfs_release_path(path);
2358 path->leave_spinning = 0;
2359 btrfs_end_transaction(trans, root);
2361 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2367 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new)
2369 struct old_sa_defrag_extent *old, *tmp;
2374 list_for_each_entry_safe(old, tmp, &new->head, list) {
2375 list_del(&old->list);
2381 static void relink_file_extents(struct new_sa_defrag_extent *new)
2383 struct btrfs_path *path;
2384 struct sa_defrag_extent_backref *backref;
2385 struct sa_defrag_extent_backref *prev = NULL;
2386 struct inode *inode;
2387 struct btrfs_root *root;
2388 struct rb_node *node;
2392 root = BTRFS_I(inode)->root;
2394 path = btrfs_alloc_path();
2398 if (!record_extent_backrefs(path, new)) {
2399 btrfs_free_path(path);
2402 btrfs_release_path(path);
2405 node = rb_first(&new->root);
2408 rb_erase(node, &new->root);
2410 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2412 ret = relink_extent_backref(path, prev, backref);
2425 btrfs_free_path(path);
2427 free_sa_defrag_extent(new);
2429 atomic_dec(&root->fs_info->defrag_running);
2430 wake_up(&root->fs_info->transaction_wait);
2433 static struct new_sa_defrag_extent *
2434 record_old_file_extents(struct inode *inode,
2435 struct btrfs_ordered_extent *ordered)
2437 struct btrfs_root *root = BTRFS_I(inode)->root;
2438 struct btrfs_path *path;
2439 struct btrfs_key key;
2440 struct old_sa_defrag_extent *old;
2441 struct new_sa_defrag_extent *new;
2444 new = kmalloc(sizeof(*new), GFP_NOFS);
2449 new->file_pos = ordered->file_offset;
2450 new->len = ordered->len;
2451 new->bytenr = ordered->start;
2452 new->disk_len = ordered->disk_len;
2453 new->compress_type = ordered->compress_type;
2454 new->root = RB_ROOT;
2455 INIT_LIST_HEAD(&new->head);
2457 path = btrfs_alloc_path();
2461 key.objectid = btrfs_ino(inode);
2462 key.type = BTRFS_EXTENT_DATA_KEY;
2463 key.offset = new->file_pos;
2465 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2468 if (ret > 0 && path->slots[0] > 0)
2471 /* find out all the old extents for the file range */
2473 struct btrfs_file_extent_item *extent;
2474 struct extent_buffer *l;
2483 slot = path->slots[0];
2485 if (slot >= btrfs_header_nritems(l)) {
2486 ret = btrfs_next_leaf(root, path);
2494 btrfs_item_key_to_cpu(l, &key, slot);
2496 if (key.objectid != btrfs_ino(inode))
2498 if (key.type != BTRFS_EXTENT_DATA_KEY)
2500 if (key.offset >= new->file_pos + new->len)
2503 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2505 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2506 if (key.offset + num_bytes < new->file_pos)
2509 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2513 extent_offset = btrfs_file_extent_offset(l, extent);
2515 old = kmalloc(sizeof(*old), GFP_NOFS);
2519 offset = max(new->file_pos, key.offset);
2520 end = min(new->file_pos + new->len, key.offset + num_bytes);
2522 old->bytenr = disk_bytenr;
2523 old->extent_offset = extent_offset;
2524 old->offset = offset - key.offset;
2525 old->len = end - offset;
2528 list_add_tail(&old->list, &new->head);
2534 btrfs_free_path(path);
2535 atomic_inc(&root->fs_info->defrag_running);
2540 btrfs_free_path(path);
2542 free_sa_defrag_extent(new);
2547 * helper function for btrfs_finish_ordered_io, this
2548 * just reads in some of the csum leaves to prime them into ram
2549 * before we start the transaction. It limits the amount of btree
2550 * reads required while inside the transaction.
2552 /* as ordered data IO finishes, this gets called so we can finish
2553 * an ordered extent if the range of bytes in the file it covers are
2556 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2558 struct inode *inode = ordered_extent->inode;
2559 struct btrfs_root *root = BTRFS_I(inode)->root;
2560 struct btrfs_trans_handle *trans = NULL;
2561 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2562 struct extent_state *cached_state = NULL;
2563 struct new_sa_defrag_extent *new = NULL;
2564 int compress_type = 0;
2566 u64 logical_len = ordered_extent->len;
2568 bool truncated = false;
2570 nolock = btrfs_is_free_space_inode(inode);
2572 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2577 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2579 logical_len = ordered_extent->truncated_len;
2580 /* Truncated the entire extent, don't bother adding */
2585 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2586 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2587 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2589 trans = btrfs_join_transaction_nolock(root);
2591 trans = btrfs_join_transaction(root);
2592 if (IS_ERR(trans)) {
2593 ret = PTR_ERR(trans);
2597 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2598 ret = btrfs_update_inode_fallback(trans, root, inode);
2599 if (ret) /* -ENOMEM or corruption */
2600 btrfs_abort_transaction(trans, root, ret);
2604 lock_extent_bits(io_tree, ordered_extent->file_offset,
2605 ordered_extent->file_offset + ordered_extent->len - 1,
2608 ret = test_range_bit(io_tree, ordered_extent->file_offset,
2609 ordered_extent->file_offset + ordered_extent->len - 1,
2610 EXTENT_DEFRAG, 1, cached_state);
2612 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2613 if (last_snapshot >= BTRFS_I(inode)->generation)
2614 /* the inode is shared */
2615 new = record_old_file_extents(inode, ordered_extent);
2617 clear_extent_bit(io_tree, ordered_extent->file_offset,
2618 ordered_extent->file_offset + ordered_extent->len - 1,
2619 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS);
2623 trans = btrfs_join_transaction_nolock(root);
2625 trans = btrfs_join_transaction(root);
2626 if (IS_ERR(trans)) {
2627 ret = PTR_ERR(trans);
2631 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2633 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
2634 compress_type = ordered_extent->compress_type;
2635 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2636 BUG_ON(compress_type);
2637 ret = btrfs_mark_extent_written(trans, inode,
2638 ordered_extent->file_offset,
2639 ordered_extent->file_offset +
2642 BUG_ON(root == root->fs_info->tree_root);
2643 ret = insert_reserved_file_extent(trans, inode,
2644 ordered_extent->file_offset,
2645 ordered_extent->start,
2646 ordered_extent->disk_len,
2647 logical_len, logical_len,
2648 compress_type, 0, 0,
2649 BTRFS_FILE_EXTENT_REG);
2651 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2652 ordered_extent->file_offset, ordered_extent->len,
2655 btrfs_abort_transaction(trans, root, ret);
2659 add_pending_csums(trans, inode, ordered_extent->file_offset,
2660 &ordered_extent->list);
2662 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2663 ret = btrfs_update_inode_fallback(trans, root, inode);
2664 if (ret) { /* -ENOMEM or corruption */
2665 btrfs_abort_transaction(trans, root, ret);
2670 unlock_extent_cached(io_tree, ordered_extent->file_offset,
2671 ordered_extent->file_offset +
2672 ordered_extent->len - 1, &cached_state, GFP_NOFS);
2674 if (root != root->fs_info->tree_root)
2675 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
2677 btrfs_end_transaction(trans, root);
2679 if (ret || truncated) {
2683 start = ordered_extent->file_offset + logical_len;
2685 start = ordered_extent->file_offset;
2686 end = ordered_extent->file_offset + ordered_extent->len - 1;
2687 clear_extent_uptodate(io_tree, start, end, NULL, GFP_NOFS);
2689 /* Drop the cache for the part of the extent we didn't write. */
2690 btrfs_drop_extent_cache(inode, start, end, 0);
2693 * If the ordered extent had an IOERR or something else went
2694 * wrong we need to return the space for this ordered extent
2695 * back to the allocator. We only free the extent in the
2696 * truncated case if we didn't write out the extent at all.
2698 if ((ret || !logical_len) &&
2699 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2700 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
2701 btrfs_free_reserved_extent(root, ordered_extent->start,
2702 ordered_extent->disk_len);
2707 * This needs to be done to make sure anybody waiting knows we are done
2708 * updating everything for this ordered extent.
2710 btrfs_remove_ordered_extent(inode, ordered_extent);
2712 /* for snapshot-aware defrag */
2715 free_sa_defrag_extent(new);
2716 atomic_dec(&root->fs_info->defrag_running);
2718 relink_file_extents(new);
2723 btrfs_put_ordered_extent(ordered_extent);
2724 /* once for the tree */
2725 btrfs_put_ordered_extent(ordered_extent);
2730 static void finish_ordered_fn(struct btrfs_work *work)
2732 struct btrfs_ordered_extent *ordered_extent;
2733 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2734 btrfs_finish_ordered_io(ordered_extent);
2737 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
2738 struct extent_state *state, int uptodate)
2740 struct inode *inode = page->mapping->host;
2741 struct btrfs_root *root = BTRFS_I(inode)->root;
2742 struct btrfs_ordered_extent *ordered_extent = NULL;
2743 struct btrfs_workers *workers;
2745 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2747 ClearPagePrivate2(page);
2748 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2749 end - start + 1, uptodate))
2752 ordered_extent->work.func = finish_ordered_fn;
2753 ordered_extent->work.flags = 0;
2755 if (btrfs_is_free_space_inode(inode))
2756 workers = &root->fs_info->endio_freespace_worker;
2758 workers = &root->fs_info->endio_write_workers;
2759 btrfs_queue_worker(workers, &ordered_extent->work);
2765 * when reads are done, we need to check csums to verify the data is correct
2766 * if there's a match, we allow the bio to finish. If not, the code in
2767 * extent_io.c will try to find good copies for us.
2769 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
2770 u64 phy_offset, struct page *page,
2771 u64 start, u64 end, int mirror)
2773 size_t offset = start - page_offset(page);
2774 struct inode *inode = page->mapping->host;
2775 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2777 struct btrfs_root *root = BTRFS_I(inode)->root;
2780 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
2781 DEFAULT_RATELIMIT_BURST);
2783 if (PageChecked(page)) {
2784 ClearPageChecked(page);
2788 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
2791 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
2792 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
2793 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
2798 phy_offset >>= inode->i_sb->s_blocksize_bits;
2799 csum_expected = *(((u32 *)io_bio->csum) + phy_offset);
2801 kaddr = kmap_atomic(page);
2802 csum = btrfs_csum_data(kaddr + offset, csum, end - start + 1);
2803 btrfs_csum_final(csum, (char *)&csum);
2804 if (csum != csum_expected)
2807 kunmap_atomic(kaddr);
2812 if (__ratelimit(&_rs))
2813 btrfs_info(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
2814 btrfs_ino(page->mapping->host), start, csum, csum_expected);
2815 memset(kaddr + offset, 1, end - start + 1);
2816 flush_dcache_page(page);
2817 kunmap_atomic(kaddr);
2818 if (csum_expected == 0)
2823 struct delayed_iput {
2824 struct list_head list;
2825 struct inode *inode;
2828 /* JDM: If this is fs-wide, why can't we add a pointer to
2829 * btrfs_inode instead and avoid the allocation? */
2830 void btrfs_add_delayed_iput(struct inode *inode)
2832 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2833 struct delayed_iput *delayed;
2835 if (atomic_add_unless(&inode->i_count, -1, 1))
2838 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2839 delayed->inode = inode;
2841 spin_lock(&fs_info->delayed_iput_lock);
2842 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2843 spin_unlock(&fs_info->delayed_iput_lock);
2846 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2849 struct btrfs_fs_info *fs_info = root->fs_info;
2850 struct delayed_iput *delayed;
2853 spin_lock(&fs_info->delayed_iput_lock);
2854 empty = list_empty(&fs_info->delayed_iputs);
2855 spin_unlock(&fs_info->delayed_iput_lock);
2859 spin_lock(&fs_info->delayed_iput_lock);
2860 list_splice_init(&fs_info->delayed_iputs, &list);
2861 spin_unlock(&fs_info->delayed_iput_lock);
2863 while (!list_empty(&list)) {
2864 delayed = list_entry(list.next, struct delayed_iput, list);
2865 list_del(&delayed->list);
2866 iput(delayed->inode);
2872 * This is called in transaction commit time. If there are no orphan
2873 * files in the subvolume, it removes orphan item and frees block_rsv
2876 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2877 struct btrfs_root *root)
2879 struct btrfs_block_rsv *block_rsv;
2882 if (atomic_read(&root->orphan_inodes) ||
2883 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2886 spin_lock(&root->orphan_lock);
2887 if (atomic_read(&root->orphan_inodes)) {
2888 spin_unlock(&root->orphan_lock);
2892 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) {
2893 spin_unlock(&root->orphan_lock);
2897 block_rsv = root->orphan_block_rsv;
2898 root->orphan_block_rsv = NULL;
2899 spin_unlock(&root->orphan_lock);
2901 if (root->orphan_item_inserted &&
2902 btrfs_root_refs(&root->root_item) > 0) {
2903 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2904 root->root_key.objectid);
2906 btrfs_abort_transaction(trans, root, ret);
2908 root->orphan_item_inserted = 0;
2912 WARN_ON(block_rsv->size > 0);
2913 btrfs_free_block_rsv(root, block_rsv);
2918 * This creates an orphan entry for the given inode in case something goes
2919 * wrong in the middle of an unlink/truncate.
2921 * NOTE: caller of this function should reserve 5 units of metadata for
2924 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2926 struct btrfs_root *root = BTRFS_I(inode)->root;
2927 struct btrfs_block_rsv *block_rsv = NULL;
2932 if (!root->orphan_block_rsv) {
2933 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
2938 spin_lock(&root->orphan_lock);
2939 if (!root->orphan_block_rsv) {
2940 root->orphan_block_rsv = block_rsv;
2941 } else if (block_rsv) {
2942 btrfs_free_block_rsv(root, block_rsv);
2946 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2947 &BTRFS_I(inode)->runtime_flags)) {
2950 * For proper ENOSPC handling, we should do orphan
2951 * cleanup when mounting. But this introduces backward
2952 * compatibility issue.
2954 if (!xchg(&root->orphan_item_inserted, 1))
2960 atomic_inc(&root->orphan_inodes);
2963 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2964 &BTRFS_I(inode)->runtime_flags))
2966 spin_unlock(&root->orphan_lock);
2968 /* grab metadata reservation from transaction handle */
2970 ret = btrfs_orphan_reserve_metadata(trans, inode);
2971 BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */
2974 /* insert an orphan item to track this unlinked/truncated file */
2976 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2978 atomic_dec(&root->orphan_inodes);
2980 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2981 &BTRFS_I(inode)->runtime_flags);
2982 btrfs_orphan_release_metadata(inode);
2984 if (ret != -EEXIST) {
2985 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2986 &BTRFS_I(inode)->runtime_flags);
2987 btrfs_abort_transaction(trans, root, ret);
2994 /* insert an orphan item to track subvolume contains orphan files */
2996 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2997 root->root_key.objectid);
2998 if (ret && ret != -EEXIST) {
2999 btrfs_abort_transaction(trans, root, ret);
3007 * We have done the truncate/delete so we can go ahead and remove the orphan
3008 * item for this particular inode.
3010 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3011 struct inode *inode)
3013 struct btrfs_root *root = BTRFS_I(inode)->root;
3014 int delete_item = 0;
3015 int release_rsv = 0;
3018 spin_lock(&root->orphan_lock);
3019 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3020 &BTRFS_I(inode)->runtime_flags))
3023 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3024 &BTRFS_I(inode)->runtime_flags))
3026 spin_unlock(&root->orphan_lock);
3029 atomic_dec(&root->orphan_inodes);
3031 ret = btrfs_del_orphan_item(trans, root,
3036 btrfs_orphan_release_metadata(inode);
3042 * this cleans up any orphans that may be left on the list from the last use
3045 int btrfs_orphan_cleanup(struct btrfs_root *root)
3047 struct btrfs_path *path;
3048 struct extent_buffer *leaf;
3049 struct btrfs_key key, found_key;
3050 struct btrfs_trans_handle *trans;
3051 struct inode *inode;
3052 u64 last_objectid = 0;
3053 int ret = 0, nr_unlink = 0, nr_truncate = 0;
3055 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3058 path = btrfs_alloc_path();
3065 key.objectid = BTRFS_ORPHAN_OBJECTID;
3066 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
3067 key.offset = (u64)-1;
3070 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3075 * if ret == 0 means we found what we were searching for, which
3076 * is weird, but possible, so only screw with path if we didn't
3077 * find the key and see if we have stuff that matches
3081 if (path->slots[0] == 0)
3086 /* pull out the item */
3087 leaf = path->nodes[0];
3088 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3090 /* make sure the item matches what we want */
3091 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3093 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
3096 /* release the path since we're done with it */
3097 btrfs_release_path(path);
3100 * this is where we are basically btrfs_lookup, without the
3101 * crossing root thing. we store the inode number in the
3102 * offset of the orphan item.
3105 if (found_key.offset == last_objectid) {
3106 btrfs_err(root->fs_info,
3107 "Error removing orphan entry, stopping orphan cleanup");
3112 last_objectid = found_key.offset;
3114 found_key.objectid = found_key.offset;
3115 found_key.type = BTRFS_INODE_ITEM_KEY;
3116 found_key.offset = 0;
3117 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
3118 ret = PTR_ERR_OR_ZERO(inode);
3119 if (ret && ret != -ESTALE)
3122 if (ret == -ESTALE && root == root->fs_info->tree_root) {
3123 struct btrfs_root *dead_root;
3124 struct btrfs_fs_info *fs_info = root->fs_info;
3125 int is_dead_root = 0;
3128 * this is an orphan in the tree root. Currently these
3129 * could come from 2 sources:
3130 * a) a snapshot deletion in progress
3131 * b) a free space cache inode
3132 * We need to distinguish those two, as the snapshot
3133 * orphan must not get deleted.
3134 * find_dead_roots already ran before us, so if this
3135 * is a snapshot deletion, we should find the root
3136 * in the dead_roots list
3138 spin_lock(&fs_info->trans_lock);
3139 list_for_each_entry(dead_root, &fs_info->dead_roots,
3141 if (dead_root->root_key.objectid ==
3142 found_key.objectid) {
3147 spin_unlock(&fs_info->trans_lock);
3149 /* prevent this orphan from being found again */
3150 key.offset = found_key.objectid - 1;
3155 * Inode is already gone but the orphan item is still there,
3156 * kill the orphan item.
3158 if (ret == -ESTALE) {
3159 trans = btrfs_start_transaction(root, 1);
3160 if (IS_ERR(trans)) {
3161 ret = PTR_ERR(trans);
3164 btrfs_debug(root->fs_info, "auto deleting %Lu",
3165 found_key.objectid);
3166 ret = btrfs_del_orphan_item(trans, root,
3167 found_key.objectid);
3168 btrfs_end_transaction(trans, root);
3175 * add this inode to the orphan list so btrfs_orphan_del does
3176 * the proper thing when we hit it
3178 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3179 &BTRFS_I(inode)->runtime_flags);
3180 atomic_inc(&root->orphan_inodes);
3182 /* if we have links, this was a truncate, lets do that */
3183 if (inode->i_nlink) {
3184 if (WARN_ON(!S_ISREG(inode->i_mode))) {
3190 /* 1 for the orphan item deletion. */
3191 trans = btrfs_start_transaction(root, 1);
3192 if (IS_ERR(trans)) {
3194 ret = PTR_ERR(trans);
3197 ret = btrfs_orphan_add(trans, inode);
3198 btrfs_end_transaction(trans, root);
3204 ret = btrfs_truncate(inode);
3206 btrfs_orphan_del(NULL, inode);
3211 /* this will do delete_inode and everything for us */
3216 /* release the path since we're done with it */
3217 btrfs_release_path(path);
3219 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3221 if (root->orphan_block_rsv)
3222 btrfs_block_rsv_release(root, root->orphan_block_rsv,
3225 if (root->orphan_block_rsv || root->orphan_item_inserted) {
3226 trans = btrfs_join_transaction(root);
3228 btrfs_end_transaction(trans, root);
3232 btrfs_debug(root->fs_info, "unlinked %d orphans", nr_unlink);
3234 btrfs_debug(root->fs_info, "truncated %d orphans", nr_truncate);
3238 btrfs_crit(root->fs_info,
3239 "could not do orphan cleanup %d", ret);
3240 btrfs_free_path(path);
3245 * very simple check to peek ahead in the leaf looking for xattrs. If we
3246 * don't find any xattrs, we know there can't be any acls.
3248 * slot is the slot the inode is in, objectid is the objectid of the inode
3250 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3251 int slot, u64 objectid)
3253 u32 nritems = btrfs_header_nritems(leaf);
3254 struct btrfs_key found_key;
3255 static u64 xattr_access = 0;
3256 static u64 xattr_default = 0;
3259 if (!xattr_access) {
3260 xattr_access = btrfs_name_hash(POSIX_ACL_XATTR_ACCESS,
3261 strlen(POSIX_ACL_XATTR_ACCESS));
3262 xattr_default = btrfs_name_hash(POSIX_ACL_XATTR_DEFAULT,
3263 strlen(POSIX_ACL_XATTR_DEFAULT));
3267 while (slot < nritems) {
3268 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3270 /* we found a different objectid, there must not be acls */
3271 if (found_key.objectid != objectid)
3274 /* we found an xattr, assume we've got an acl */
3275 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3276 if (found_key.offset == xattr_access ||
3277 found_key.offset == xattr_default)
3282 * we found a key greater than an xattr key, there can't
3283 * be any acls later on
3285 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3292 * it goes inode, inode backrefs, xattrs, extents,
3293 * so if there are a ton of hard links to an inode there can
3294 * be a lot of backrefs. Don't waste time searching too hard,
3295 * this is just an optimization
3300 /* we hit the end of the leaf before we found an xattr or
3301 * something larger than an xattr. We have to assume the inode
3308 * read an inode from the btree into the in-memory inode
3310 static void btrfs_read_locked_inode(struct inode *inode)
3312 struct btrfs_path *path;
3313 struct extent_buffer *leaf;
3314 struct btrfs_inode_item *inode_item;
3315 struct btrfs_timespec *tspec;
3316 struct btrfs_root *root = BTRFS_I(inode)->root;
3317 struct btrfs_key location;
3321 bool filled = false;
3323 ret = btrfs_fill_inode(inode, &rdev);
3327 path = btrfs_alloc_path();
3331 path->leave_spinning = 1;
3332 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3334 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3338 leaf = path->nodes[0];
3343 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3344 struct btrfs_inode_item);
3345 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3346 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3347 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3348 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3349 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
3351 tspec = btrfs_inode_atime(inode_item);
3352 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3353 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3355 tspec = btrfs_inode_mtime(inode_item);
3356 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3357 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3359 tspec = btrfs_inode_ctime(inode_item);
3360 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3361 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3363 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3364 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3365 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3368 * If we were modified in the current generation and evicted from memory
3369 * and then re-read we need to do a full sync since we don't have any
3370 * idea about which extents were modified before we were evicted from
3373 if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
3374 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3375 &BTRFS_I(inode)->runtime_flags);
3377 inode->i_version = btrfs_inode_sequence(leaf, inode_item);
3378 inode->i_generation = BTRFS_I(inode)->generation;
3380 rdev = btrfs_inode_rdev(leaf, inode_item);
3382 BTRFS_I(inode)->index_cnt = (u64)-1;
3383 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3386 * try to precache a NULL acl entry for files that don't have
3387 * any xattrs or acls
3389 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3392 cache_no_acl(inode);
3394 btrfs_free_path(path);
3396 switch (inode->i_mode & S_IFMT) {
3398 inode->i_mapping->a_ops = &btrfs_aops;
3399 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3400 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3401 inode->i_fop = &btrfs_file_operations;
3402 inode->i_op = &btrfs_file_inode_operations;
3405 inode->i_fop = &btrfs_dir_file_operations;
3406 if (root == root->fs_info->tree_root)
3407 inode->i_op = &btrfs_dir_ro_inode_operations;
3409 inode->i_op = &btrfs_dir_inode_operations;
3412 inode->i_op = &btrfs_symlink_inode_operations;
3413 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3414 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3417 inode->i_op = &btrfs_special_inode_operations;
3418 init_special_inode(inode, inode->i_mode, rdev);
3422 btrfs_update_iflags(inode);
3426 btrfs_free_path(path);
3427 make_bad_inode(inode);
3431 * given a leaf and an inode, copy the inode fields into the leaf
3433 static void fill_inode_item(struct btrfs_trans_handle *trans,
3434 struct extent_buffer *leaf,
3435 struct btrfs_inode_item *item,
3436 struct inode *inode)
3438 struct btrfs_map_token token;
3440 btrfs_init_map_token(&token);
3442 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3443 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3444 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3446 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3447 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3449 btrfs_set_token_timespec_sec(leaf, btrfs_inode_atime(item),
3450 inode->i_atime.tv_sec, &token);
3451 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_atime(item),
3452 inode->i_atime.tv_nsec, &token);
3454 btrfs_set_token_timespec_sec(leaf, btrfs_inode_mtime(item),
3455 inode->i_mtime.tv_sec, &token);
3456 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_mtime(item),
3457 inode->i_mtime.tv_nsec, &token);
3459 btrfs_set_token_timespec_sec(leaf, btrfs_inode_ctime(item),
3460 inode->i_ctime.tv_sec, &token);
3461 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_ctime(item),
3462 inode->i_ctime.tv_nsec, &token);
3464 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3466 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3468 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token);
3469 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3470 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3471 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3472 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3476 * copy everything in the in-memory inode into the btree.
3478 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3479 struct btrfs_root *root, struct inode *inode)
3481 struct btrfs_inode_item *inode_item;
3482 struct btrfs_path *path;
3483 struct extent_buffer *leaf;
3486 path = btrfs_alloc_path();
3490 path->leave_spinning = 1;
3491 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3499 btrfs_unlock_up_safe(path, 1);
3500 leaf = path->nodes[0];
3501 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3502 struct btrfs_inode_item);
3504 fill_inode_item(trans, leaf, inode_item, inode);
3505 btrfs_mark_buffer_dirty(leaf);
3506 btrfs_set_inode_last_trans(trans, inode);
3509 btrfs_free_path(path);
3514 * copy everything in the in-memory inode into the btree.
3516 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3517 struct btrfs_root *root, struct inode *inode)
3522 * If the inode is a free space inode, we can deadlock during commit
3523 * if we put it into the delayed code.
3525 * The data relocation inode should also be directly updated
3528 if (!btrfs_is_free_space_inode(inode)
3529 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
3530 btrfs_update_root_times(trans, root);
3532 ret = btrfs_delayed_update_inode(trans, root, inode);
3534 btrfs_set_inode_last_trans(trans, inode);
3538 return btrfs_update_inode_item(trans, root, inode);
3541 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3542 struct btrfs_root *root,
3543 struct inode *inode)
3547 ret = btrfs_update_inode(trans, root, inode);
3549 return btrfs_update_inode_item(trans, root, inode);
3554 * unlink helper that gets used here in inode.c and in the tree logging
3555 * recovery code. It remove a link in a directory with a given name, and
3556 * also drops the back refs in the inode to the directory
3558 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3559 struct btrfs_root *root,
3560 struct inode *dir, struct inode *inode,
3561 const char *name, int name_len)
3563 struct btrfs_path *path;
3565 struct extent_buffer *leaf;
3566 struct btrfs_dir_item *di;
3567 struct btrfs_key key;
3569 u64 ino = btrfs_ino(inode);
3570 u64 dir_ino = btrfs_ino(dir);
3572 path = btrfs_alloc_path();
3578 path->leave_spinning = 1;
3579 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3580 name, name_len, -1);
3589 leaf = path->nodes[0];
3590 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3591 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3594 btrfs_release_path(path);
3596 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3599 btrfs_info(root->fs_info,
3600 "failed to delete reference to %.*s, inode %llu parent %llu",
3601 name_len, name, ino, dir_ino);
3602 btrfs_abort_transaction(trans, root, ret);
3606 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3608 btrfs_abort_transaction(trans, root, ret);
3612 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
3614 if (ret != 0 && ret != -ENOENT) {
3615 btrfs_abort_transaction(trans, root, ret);
3619 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
3624 btrfs_abort_transaction(trans, root, ret);
3626 btrfs_free_path(path);
3630 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3631 inode_inc_iversion(inode);
3632 inode_inc_iversion(dir);
3633 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3634 ret = btrfs_update_inode(trans, root, dir);
3639 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3640 struct btrfs_root *root,
3641 struct inode *dir, struct inode *inode,
3642 const char *name, int name_len)
3645 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3648 ret = btrfs_update_inode(trans, root, inode);
3654 * helper to start transaction for unlink and rmdir.
3656 * unlink and rmdir are special in btrfs, they do not always free space, so
3657 * if we cannot make our reservations the normal way try and see if there is
3658 * plenty of slack room in the global reserve to migrate, otherwise we cannot
3659 * allow the unlink to occur.
3661 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
3663 struct btrfs_trans_handle *trans;
3664 struct btrfs_root *root = BTRFS_I(dir)->root;
3668 * 1 for the possible orphan item
3669 * 1 for the dir item
3670 * 1 for the dir index
3671 * 1 for the inode ref
3674 trans = btrfs_start_transaction(root, 5);
3675 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
3678 if (PTR_ERR(trans) == -ENOSPC) {
3679 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3681 trans = btrfs_start_transaction(root, 0);
3684 ret = btrfs_cond_migrate_bytes(root->fs_info,
3685 &root->fs_info->trans_block_rsv,
3688 btrfs_end_transaction(trans, root);
3689 return ERR_PTR(ret);
3691 trans->block_rsv = &root->fs_info->trans_block_rsv;
3692 trans->bytes_reserved = num_bytes;
3697 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3699 struct btrfs_root *root = BTRFS_I(dir)->root;
3700 struct btrfs_trans_handle *trans;
3701 struct inode *inode = dentry->d_inode;
3704 trans = __unlink_start_trans(dir);
3706 return PTR_ERR(trans);
3708 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3710 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3711 dentry->d_name.name, dentry->d_name.len);
3715 if (inode->i_nlink == 0) {
3716 ret = btrfs_orphan_add(trans, inode);
3722 btrfs_end_transaction(trans, root);
3723 btrfs_btree_balance_dirty(root);
3727 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3728 struct btrfs_root *root,
3729 struct inode *dir, u64 objectid,
3730 const char *name, int name_len)
3732 struct btrfs_path *path;
3733 struct extent_buffer *leaf;
3734 struct btrfs_dir_item *di;
3735 struct btrfs_key key;
3738 u64 dir_ino = btrfs_ino(dir);
3740 path = btrfs_alloc_path();
3744 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3745 name, name_len, -1);
3746 if (IS_ERR_OR_NULL(di)) {
3754 leaf = path->nodes[0];
3755 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3756 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3757 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3759 btrfs_abort_transaction(trans, root, ret);
3762 btrfs_release_path(path);
3764 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3765 objectid, root->root_key.objectid,
3766 dir_ino, &index, name, name_len);
3768 if (ret != -ENOENT) {
3769 btrfs_abort_transaction(trans, root, ret);
3772 di = btrfs_search_dir_index_item(root, path, dir_ino,
3774 if (IS_ERR_OR_NULL(di)) {
3779 btrfs_abort_transaction(trans, root, ret);
3783 leaf = path->nodes[0];
3784 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3785 btrfs_release_path(path);
3788 btrfs_release_path(path);
3790 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3792 btrfs_abort_transaction(trans, root, ret);
3796 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3797 inode_inc_iversion(dir);
3798 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3799 ret = btrfs_update_inode_fallback(trans, root, dir);
3801 btrfs_abort_transaction(trans, root, ret);
3803 btrfs_free_path(path);
3807 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3809 struct inode *inode = dentry->d_inode;
3811 struct btrfs_root *root = BTRFS_I(dir)->root;
3812 struct btrfs_trans_handle *trans;
3814 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
3816 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3819 trans = __unlink_start_trans(dir);
3821 return PTR_ERR(trans);
3823 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3824 err = btrfs_unlink_subvol(trans, root, dir,
3825 BTRFS_I(inode)->location.objectid,
3826 dentry->d_name.name,
3827 dentry->d_name.len);
3831 err = btrfs_orphan_add(trans, inode);
3835 /* now the directory is empty */
3836 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3837 dentry->d_name.name, dentry->d_name.len);
3839 btrfs_i_size_write(inode, 0);
3841 btrfs_end_transaction(trans, root);
3842 btrfs_btree_balance_dirty(root);
3848 * this can truncate away extent items, csum items and directory items.
3849 * It starts at a high offset and removes keys until it can't find
3850 * any higher than new_size
3852 * csum items that cross the new i_size are truncated to the new size
3855 * min_type is the minimum key type to truncate down to. If set to 0, this
3856 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3858 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3859 struct btrfs_root *root,
3860 struct inode *inode,
3861 u64 new_size, u32 min_type)
3863 struct btrfs_path *path;
3864 struct extent_buffer *leaf;
3865 struct btrfs_file_extent_item *fi;
3866 struct btrfs_key key;
3867 struct btrfs_key found_key;
3868 u64 extent_start = 0;
3869 u64 extent_num_bytes = 0;
3870 u64 extent_offset = 0;
3872 u64 last_size = (u64)-1;
3873 u32 found_type = (u8)-1;
3876 int pending_del_nr = 0;
3877 int pending_del_slot = 0;
3878 int extent_type = -1;
3881 u64 ino = btrfs_ino(inode);
3883 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3885 path = btrfs_alloc_path();
3891 * We want to drop from the next block forward in case this new size is
3892 * not block aligned since we will be keeping the last block of the
3893 * extent just the way it is.
3895 if (root->ref_cows || root == root->fs_info->tree_root)
3896 btrfs_drop_extent_cache(inode, ALIGN(new_size,
3897 root->sectorsize), (u64)-1, 0);
3900 * This function is also used to drop the items in the log tree before
3901 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3902 * it is used to drop the loged items. So we shouldn't kill the delayed
3905 if (min_type == 0 && root == BTRFS_I(inode)->root)
3906 btrfs_kill_delayed_inode_items(inode);
3909 key.offset = (u64)-1;
3913 path->leave_spinning = 1;
3914 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3921 /* there are no items in the tree for us to truncate, we're
3924 if (path->slots[0] == 0)
3931 leaf = path->nodes[0];
3932 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3933 found_type = btrfs_key_type(&found_key);
3935 if (found_key.objectid != ino)
3938 if (found_type < min_type)
3941 item_end = found_key.offset;
3942 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3943 fi = btrfs_item_ptr(leaf, path->slots[0],
3944 struct btrfs_file_extent_item);
3945 extent_type = btrfs_file_extent_type(leaf, fi);
3946 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3948 btrfs_file_extent_num_bytes(leaf, fi);
3949 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3950 item_end += btrfs_file_extent_inline_len(leaf,
3955 if (found_type > min_type) {
3958 if (item_end < new_size)
3960 if (found_key.offset >= new_size)
3966 /* FIXME, shrink the extent if the ref count is only 1 */
3967 if (found_type != BTRFS_EXTENT_DATA_KEY)
3971 last_size = found_key.offset;
3973 last_size = new_size;
3975 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3977 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3979 u64 orig_num_bytes =
3980 btrfs_file_extent_num_bytes(leaf, fi);
3981 extent_num_bytes = ALIGN(new_size -
3984 btrfs_set_file_extent_num_bytes(leaf, fi,
3986 num_dec = (orig_num_bytes -
3988 if (root->ref_cows && extent_start != 0)
3989 inode_sub_bytes(inode, num_dec);
3990 btrfs_mark_buffer_dirty(leaf);
3993 btrfs_file_extent_disk_num_bytes(leaf,
3995 extent_offset = found_key.offset -
3996 btrfs_file_extent_offset(leaf, fi);
3998 /* FIXME blocksize != 4096 */
3999 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4000 if (extent_start != 0) {
4003 inode_sub_bytes(inode, num_dec);
4006 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4008 * we can't truncate inline items that have had
4012 btrfs_file_extent_compression(leaf, fi) == 0 &&
4013 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4014 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
4015 u32 size = new_size - found_key.offset;
4017 if (root->ref_cows) {
4018 inode_sub_bytes(inode, item_end + 1 -
4022 btrfs_file_extent_calc_inline_size(size);
4023 btrfs_truncate_item(root, path, size, 1);
4024 } else if (root->ref_cows) {
4025 inode_sub_bytes(inode, item_end + 1 -
4031 if (!pending_del_nr) {
4032 /* no pending yet, add ourselves */
4033 pending_del_slot = path->slots[0];
4035 } else if (pending_del_nr &&
4036 path->slots[0] + 1 == pending_del_slot) {
4037 /* hop on the pending chunk */
4039 pending_del_slot = path->slots[0];
4046 if (found_extent && (root->ref_cows ||
4047 root == root->fs_info->tree_root)) {
4048 btrfs_set_path_blocking(path);
4049 ret = btrfs_free_extent(trans, root, extent_start,
4050 extent_num_bytes, 0,
4051 btrfs_header_owner(leaf),
4052 ino, extent_offset, 0);
4056 if (found_type == BTRFS_INODE_ITEM_KEY)
4059 if (path->slots[0] == 0 ||
4060 path->slots[0] != pending_del_slot) {
4061 if (pending_del_nr) {
4062 ret = btrfs_del_items(trans, root, path,
4066 btrfs_abort_transaction(trans,
4072 btrfs_release_path(path);
4079 if (pending_del_nr) {
4080 ret = btrfs_del_items(trans, root, path, pending_del_slot,
4083 btrfs_abort_transaction(trans, root, ret);
4086 if (last_size != (u64)-1)
4087 btrfs_ordered_update_i_size(inode, last_size, NULL);
4088 btrfs_free_path(path);
4093 * btrfs_truncate_page - read, zero a chunk and write a page
4094 * @inode - inode that we're zeroing
4095 * @from - the offset to start zeroing
4096 * @len - the length to zero, 0 to zero the entire range respective to the
4098 * @front - zero up to the offset instead of from the offset on
4100 * This will find the page for the "from" offset and cow the page and zero the
4101 * part we want to zero. This is used with truncate and hole punching.
4103 int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
4106 struct address_space *mapping = inode->i_mapping;
4107 struct btrfs_root *root = BTRFS_I(inode)->root;
4108 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4109 struct btrfs_ordered_extent *ordered;
4110 struct extent_state *cached_state = NULL;
4112 u32 blocksize = root->sectorsize;
4113 pgoff_t index = from >> PAGE_CACHE_SHIFT;
4114 unsigned offset = from & (PAGE_CACHE_SIZE-1);
4116 gfp_t mask = btrfs_alloc_write_mask(mapping);
4121 if ((offset & (blocksize - 1)) == 0 &&
4122 (!len || ((len & (blocksize - 1)) == 0)))
4124 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
4129 page = find_or_create_page(mapping, index, mask);
4131 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4136 page_start = page_offset(page);
4137 page_end = page_start + PAGE_CACHE_SIZE - 1;
4139 if (!PageUptodate(page)) {
4140 ret = btrfs_readpage(NULL, page);
4142 if (page->mapping != mapping) {
4144 page_cache_release(page);
4147 if (!PageUptodate(page)) {
4152 wait_on_page_writeback(page);
4154 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
4155 set_page_extent_mapped(page);
4157 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4159 unlock_extent_cached(io_tree, page_start, page_end,
4160 &cached_state, GFP_NOFS);
4162 page_cache_release(page);
4163 btrfs_start_ordered_extent(inode, ordered, 1);
4164 btrfs_put_ordered_extent(ordered);
4168 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
4169 EXTENT_DIRTY | EXTENT_DELALLOC |
4170 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4171 0, 0, &cached_state, GFP_NOFS);
4173 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
4176 unlock_extent_cached(io_tree, page_start, page_end,
4177 &cached_state, GFP_NOFS);
4181 if (offset != PAGE_CACHE_SIZE) {
4183 len = PAGE_CACHE_SIZE - offset;
4186 memset(kaddr, 0, offset);
4188 memset(kaddr + offset, 0, len);
4189 flush_dcache_page(page);
4192 ClearPageChecked(page);
4193 set_page_dirty(page);
4194 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
4199 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4201 page_cache_release(page);
4206 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4207 u64 offset, u64 len)
4209 struct btrfs_trans_handle *trans;
4213 * Still need to make sure the inode looks like it's been updated so
4214 * that any holes get logged if we fsync.
4216 if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) {
4217 BTRFS_I(inode)->last_trans = root->fs_info->generation;
4218 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4219 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4224 * 1 - for the one we're dropping
4225 * 1 - for the one we're adding
4226 * 1 - for updating the inode.
4228 trans = btrfs_start_transaction(root, 3);
4230 return PTR_ERR(trans);
4232 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4234 btrfs_abort_transaction(trans, root, ret);
4235 btrfs_end_transaction(trans, root);
4239 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset,
4240 0, 0, len, 0, len, 0, 0, 0);
4242 btrfs_abort_transaction(trans, root, ret);
4244 btrfs_update_inode(trans, root, inode);
4245 btrfs_end_transaction(trans, root);
4250 * This function puts in dummy file extents for the area we're creating a hole
4251 * for. So if we are truncating this file to a larger size we need to insert
4252 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4253 * the range between oldsize and size
4255 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4257 struct btrfs_root *root = BTRFS_I(inode)->root;
4258 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4259 struct extent_map *em = NULL;
4260 struct extent_state *cached_state = NULL;
4261 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4262 u64 hole_start = ALIGN(oldsize, root->sectorsize);
4263 u64 block_end = ALIGN(size, root->sectorsize);
4270 * If our size started in the middle of a page we need to zero out the
4271 * rest of the page before we expand the i_size, otherwise we could
4272 * expose stale data.
4274 err = btrfs_truncate_page(inode, oldsize, 0, 0);
4278 if (size <= hole_start)
4282 struct btrfs_ordered_extent *ordered;
4284 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
4286 ordered = btrfs_lookup_ordered_range(inode, hole_start,
4287 block_end - hole_start);
4290 unlock_extent_cached(io_tree, hole_start, block_end - 1,
4291 &cached_state, GFP_NOFS);
4292 btrfs_start_ordered_extent(inode, ordered, 1);
4293 btrfs_put_ordered_extent(ordered);
4296 cur_offset = hole_start;
4298 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
4299 block_end - cur_offset, 0);
4305 last_byte = min(extent_map_end(em), block_end);
4306 last_byte = ALIGN(last_byte , root->sectorsize);
4307 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
4308 struct extent_map *hole_em;
4309 hole_size = last_byte - cur_offset;
4311 err = maybe_insert_hole(root, inode, cur_offset,
4315 btrfs_drop_extent_cache(inode, cur_offset,
4316 cur_offset + hole_size - 1, 0);
4317 hole_em = alloc_extent_map();
4319 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4320 &BTRFS_I(inode)->runtime_flags);
4323 hole_em->start = cur_offset;
4324 hole_em->len = hole_size;
4325 hole_em->orig_start = cur_offset;
4327 hole_em->block_start = EXTENT_MAP_HOLE;
4328 hole_em->block_len = 0;
4329 hole_em->orig_block_len = 0;
4330 hole_em->ram_bytes = hole_size;
4331 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
4332 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4333 hole_em->generation = root->fs_info->generation;
4336 write_lock(&em_tree->lock);
4337 err = add_extent_mapping(em_tree, hole_em, 1);
4338 write_unlock(&em_tree->lock);
4341 btrfs_drop_extent_cache(inode, cur_offset,
4345 free_extent_map(hole_em);
4348 free_extent_map(em);
4350 cur_offset = last_byte;
4351 if (cur_offset >= block_end)
4354 free_extent_map(em);
4355 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
4360 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
4362 struct btrfs_root *root = BTRFS_I(inode)->root;
4363 struct btrfs_trans_handle *trans;
4364 loff_t oldsize = i_size_read(inode);
4365 loff_t newsize = attr->ia_size;
4366 int mask = attr->ia_valid;
4370 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4371 * special case where we need to update the times despite not having
4372 * these flags set. For all other operations the VFS set these flags
4373 * explicitly if it wants a timestamp update.
4375 if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
4376 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
4378 if (newsize > oldsize) {
4379 truncate_pagecache(inode, newsize);
4380 ret = btrfs_cont_expand(inode, oldsize, newsize);
4384 trans = btrfs_start_transaction(root, 1);
4386 return PTR_ERR(trans);
4388 i_size_write(inode, newsize);
4389 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
4390 ret = btrfs_update_inode(trans, root, inode);
4391 btrfs_end_transaction(trans, root);
4395 * We're truncating a file that used to have good data down to
4396 * zero. Make sure it gets into the ordered flush list so that
4397 * any new writes get down to disk quickly.
4400 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4401 &BTRFS_I(inode)->runtime_flags);
4404 * 1 for the orphan item we're going to add
4405 * 1 for the orphan item deletion.
4407 trans = btrfs_start_transaction(root, 2);
4409 return PTR_ERR(trans);
4412 * We need to do this in case we fail at _any_ point during the
4413 * actual truncate. Once we do the truncate_setsize we could
4414 * invalidate pages which forces any outstanding ordered io to
4415 * be instantly completed which will give us extents that need
4416 * to be truncated. If we fail to get an orphan inode down we
4417 * could have left over extents that were never meant to live,
4418 * so we need to garuntee from this point on that everything
4419 * will be consistent.
4421 ret = btrfs_orphan_add(trans, inode);
4422 btrfs_end_transaction(trans, root);
4426 /* we don't support swapfiles, so vmtruncate shouldn't fail */
4427 truncate_setsize(inode, newsize);
4429 /* Disable nonlocked read DIO to avoid the end less truncate */
4430 btrfs_inode_block_unlocked_dio(inode);
4431 inode_dio_wait(inode);
4432 btrfs_inode_resume_unlocked_dio(inode);
4434 ret = btrfs_truncate(inode);
4435 if (ret && inode->i_nlink) {
4439 * failed to truncate, disk_i_size is only adjusted down
4440 * as we remove extents, so it should represent the true
4441 * size of the inode, so reset the in memory size and
4442 * delete our orphan entry.
4444 trans = btrfs_join_transaction(root);
4445 if (IS_ERR(trans)) {
4446 btrfs_orphan_del(NULL, inode);
4449 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
4450 err = btrfs_orphan_del(trans, inode);
4452 btrfs_abort_transaction(trans, root, err);
4453 btrfs_end_transaction(trans, root);
4460 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4462 struct inode *inode = dentry->d_inode;
4463 struct btrfs_root *root = BTRFS_I(inode)->root;
4466 if (btrfs_root_readonly(root))
4469 err = inode_change_ok(inode, attr);
4473 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
4474 err = btrfs_setsize(inode, attr);
4479 if (attr->ia_valid) {
4480 setattr_copy(inode, attr);
4481 inode_inc_iversion(inode);
4482 err = btrfs_dirty_inode(inode);
4484 if (!err && attr->ia_valid & ATTR_MODE)
4485 err = btrfs_acl_chmod(inode);
4491 void btrfs_evict_inode(struct inode *inode)
4493 struct btrfs_trans_handle *trans;
4494 struct btrfs_root *root = BTRFS_I(inode)->root;
4495 struct btrfs_block_rsv *rsv, *global_rsv;
4496 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
4499 trace_btrfs_inode_evict(inode);
4501 truncate_inode_pages(&inode->i_data, 0);
4502 if (inode->i_nlink &&
4503 ((btrfs_root_refs(&root->root_item) != 0 &&
4504 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
4505 btrfs_is_free_space_inode(inode)))
4508 if (is_bad_inode(inode)) {
4509 btrfs_orphan_del(NULL, inode);
4512 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
4513 btrfs_wait_ordered_range(inode, 0, (u64)-1);
4515 if (root->fs_info->log_root_recovering) {
4516 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
4517 &BTRFS_I(inode)->runtime_flags));
4521 if (inode->i_nlink > 0) {
4522 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
4523 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
4527 ret = btrfs_commit_inode_delayed_inode(inode);
4529 btrfs_orphan_del(NULL, inode);
4533 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
4535 btrfs_orphan_del(NULL, inode);
4538 rsv->size = min_size;
4540 global_rsv = &root->fs_info->global_block_rsv;
4542 btrfs_i_size_write(inode, 0);
4545 * This is a bit simpler than btrfs_truncate since we've already
4546 * reserved our space for our orphan item in the unlink, so we just
4547 * need to reserve some slack space in case we add bytes and update
4548 * inode item when doing the truncate.
4551 ret = btrfs_block_rsv_refill(root, rsv, min_size,
4552 BTRFS_RESERVE_FLUSH_LIMIT);
4555 * Try and steal from the global reserve since we will
4556 * likely not use this space anyway, we want to try as
4557 * hard as possible to get this to work.
4560 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
4563 btrfs_warn(root->fs_info,
4564 "Could not get space for a delete, will truncate on mount %d",
4566 btrfs_orphan_del(NULL, inode);
4567 btrfs_free_block_rsv(root, rsv);
4571 trans = btrfs_join_transaction(root);
4572 if (IS_ERR(trans)) {
4573 btrfs_orphan_del(NULL, inode);
4574 btrfs_free_block_rsv(root, rsv);
4578 trans->block_rsv = rsv;
4580 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
4584 trans->block_rsv = &root->fs_info->trans_block_rsv;
4585 btrfs_end_transaction(trans, root);
4587 btrfs_btree_balance_dirty(root);
4590 btrfs_free_block_rsv(root, rsv);
4593 * Errors here aren't a big deal, it just means we leave orphan items
4594 * in the tree. They will be cleaned up on the next mount.
4597 trans->block_rsv = root->orphan_block_rsv;
4598 btrfs_orphan_del(trans, inode);
4600 btrfs_orphan_del(NULL, inode);
4603 trans->block_rsv = &root->fs_info->trans_block_rsv;
4604 if (!(root == root->fs_info->tree_root ||
4605 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
4606 btrfs_return_ino(root, btrfs_ino(inode));
4608 btrfs_end_transaction(trans, root);
4609 btrfs_btree_balance_dirty(root);
4611 btrfs_remove_delayed_node(inode);
4617 * this returns the key found in the dir entry in the location pointer.
4618 * If no dir entries were found, location->objectid is 0.
4620 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
4621 struct btrfs_key *location)
4623 const char *name = dentry->d_name.name;
4624 int namelen = dentry->d_name.len;
4625 struct btrfs_dir_item *di;
4626 struct btrfs_path *path;
4627 struct btrfs_root *root = BTRFS_I(dir)->root;
4630 path = btrfs_alloc_path();
4634 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
4639 if (IS_ERR_OR_NULL(di))
4642 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
4644 btrfs_free_path(path);
4647 location->objectid = 0;
4652 * when we hit a tree root in a directory, the btrfs part of the inode
4653 * needs to be changed to reflect the root directory of the tree root. This
4654 * is kind of like crossing a mount point.
4656 static int fixup_tree_root_location(struct btrfs_root *root,
4658 struct dentry *dentry,
4659 struct btrfs_key *location,
4660 struct btrfs_root **sub_root)
4662 struct btrfs_path *path;
4663 struct btrfs_root *new_root;
4664 struct btrfs_root_ref *ref;
4665 struct extent_buffer *leaf;
4669 path = btrfs_alloc_path();
4676 ret = btrfs_find_item(root->fs_info->tree_root, path,
4677 BTRFS_I(dir)->root->root_key.objectid,
4678 location->objectid, BTRFS_ROOT_REF_KEY, NULL);
4685 leaf = path->nodes[0];
4686 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
4687 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
4688 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
4691 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
4692 (unsigned long)(ref + 1),
4693 dentry->d_name.len);
4697 btrfs_release_path(path);
4699 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
4700 if (IS_ERR(new_root)) {
4701 err = PTR_ERR(new_root);
4705 *sub_root = new_root;
4706 location->objectid = btrfs_root_dirid(&new_root->root_item);
4707 location->type = BTRFS_INODE_ITEM_KEY;
4708 location->offset = 0;
4711 btrfs_free_path(path);
4715 static void inode_tree_add(struct inode *inode)
4717 struct btrfs_root *root = BTRFS_I(inode)->root;
4718 struct btrfs_inode *entry;
4720 struct rb_node *parent;
4721 struct rb_node *new = &BTRFS_I(inode)->rb_node;
4722 u64 ino = btrfs_ino(inode);
4724 if (inode_unhashed(inode))
4727 spin_lock(&root->inode_lock);
4728 p = &root->inode_tree.rb_node;
4731 entry = rb_entry(parent, struct btrfs_inode, rb_node);
4733 if (ino < btrfs_ino(&entry->vfs_inode))
4734 p = &parent->rb_left;
4735 else if (ino > btrfs_ino(&entry->vfs_inode))
4736 p = &parent->rb_right;
4738 WARN_ON(!(entry->vfs_inode.i_state &
4739 (I_WILL_FREE | I_FREEING)));
4740 rb_replace_node(parent, new, &root->inode_tree);
4741 RB_CLEAR_NODE(parent);
4742 spin_unlock(&root->inode_lock);
4746 rb_link_node(new, parent, p);
4747 rb_insert_color(new, &root->inode_tree);
4748 spin_unlock(&root->inode_lock);
4751 static void inode_tree_del(struct inode *inode)
4753 struct btrfs_root *root = BTRFS_I(inode)->root;
4756 spin_lock(&root->inode_lock);
4757 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
4758 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4759 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
4760 empty = RB_EMPTY_ROOT(&root->inode_tree);
4762 spin_unlock(&root->inode_lock);
4764 if (empty && btrfs_root_refs(&root->root_item) == 0) {
4765 synchronize_srcu(&root->fs_info->subvol_srcu);
4766 spin_lock(&root->inode_lock);
4767 empty = RB_EMPTY_ROOT(&root->inode_tree);
4768 spin_unlock(&root->inode_lock);
4770 btrfs_add_dead_root(root);
4774 void btrfs_invalidate_inodes(struct btrfs_root *root)
4776 struct rb_node *node;
4777 struct rb_node *prev;
4778 struct btrfs_inode *entry;
4779 struct inode *inode;
4782 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4784 spin_lock(&root->inode_lock);
4786 node = root->inode_tree.rb_node;
4790 entry = rb_entry(node, struct btrfs_inode, rb_node);
4792 if (objectid < btrfs_ino(&entry->vfs_inode))
4793 node = node->rb_left;
4794 else if (objectid > btrfs_ino(&entry->vfs_inode))
4795 node = node->rb_right;
4801 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4802 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
4806 prev = rb_next(prev);
4810 entry = rb_entry(node, struct btrfs_inode, rb_node);
4811 objectid = btrfs_ino(&entry->vfs_inode) + 1;
4812 inode = igrab(&entry->vfs_inode);
4814 spin_unlock(&root->inode_lock);
4815 if (atomic_read(&inode->i_count) > 1)
4816 d_prune_aliases(inode);
4818 * btrfs_drop_inode will have it removed from
4819 * the inode cache when its usage count
4824 spin_lock(&root->inode_lock);
4828 if (cond_resched_lock(&root->inode_lock))
4831 node = rb_next(node);
4833 spin_unlock(&root->inode_lock);
4836 static int btrfs_init_locked_inode(struct inode *inode, void *p)
4838 struct btrfs_iget_args *args = p;
4839 inode->i_ino = args->ino;
4840 BTRFS_I(inode)->root = args->root;
4844 static int btrfs_find_actor(struct inode *inode, void *opaque)
4846 struct btrfs_iget_args *args = opaque;
4847 return args->ino == btrfs_ino(inode) &&
4848 args->root == BTRFS_I(inode)->root;
4851 static struct inode *btrfs_iget_locked(struct super_block *s,
4853 struct btrfs_root *root)
4855 struct inode *inode;
4856 struct btrfs_iget_args args;
4857 unsigned long hashval = btrfs_inode_hash(objectid, root);
4859 args.ino = objectid;
4862 inode = iget5_locked(s, hashval, btrfs_find_actor,
4863 btrfs_init_locked_inode,
4868 /* Get an inode object given its location and corresponding root.
4869 * Returns in *is_new if the inode was read from disk
4871 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
4872 struct btrfs_root *root, int *new)
4874 struct inode *inode;
4876 inode = btrfs_iget_locked(s, location->objectid, root);
4878 return ERR_PTR(-ENOMEM);
4880 if (inode->i_state & I_NEW) {
4881 BTRFS_I(inode)->root = root;
4882 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
4883 btrfs_read_locked_inode(inode);
4884 if (!is_bad_inode(inode)) {
4885 inode_tree_add(inode);
4886 unlock_new_inode(inode);
4890 unlock_new_inode(inode);
4892 inode = ERR_PTR(-ESTALE);
4899 static struct inode *new_simple_dir(struct super_block *s,
4900 struct btrfs_key *key,
4901 struct btrfs_root *root)
4903 struct inode *inode = new_inode(s);
4906 return ERR_PTR(-ENOMEM);
4908 BTRFS_I(inode)->root = root;
4909 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
4910 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
4912 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
4913 inode->i_op = &btrfs_dir_ro_inode_operations;
4914 inode->i_fop = &simple_dir_operations;
4915 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
4916 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4921 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
4923 struct inode *inode;
4924 struct btrfs_root *root = BTRFS_I(dir)->root;
4925 struct btrfs_root *sub_root = root;
4926 struct btrfs_key location;
4930 if (dentry->d_name.len > BTRFS_NAME_LEN)
4931 return ERR_PTR(-ENAMETOOLONG);
4933 ret = btrfs_inode_by_name(dir, dentry, &location);
4935 return ERR_PTR(ret);
4937 if (location.objectid == 0)
4940 if (location.type == BTRFS_INODE_ITEM_KEY) {
4941 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
4945 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
4947 index = srcu_read_lock(&root->fs_info->subvol_srcu);
4948 ret = fixup_tree_root_location(root, dir, dentry,
4949 &location, &sub_root);
4952 inode = ERR_PTR(ret);
4954 inode = new_simple_dir(dir->i_sb, &location, sub_root);
4956 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
4958 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
4960 if (!IS_ERR(inode) && root != sub_root) {
4961 down_read(&root->fs_info->cleanup_work_sem);
4962 if (!(inode->i_sb->s_flags & MS_RDONLY))
4963 ret = btrfs_orphan_cleanup(sub_root);
4964 up_read(&root->fs_info->cleanup_work_sem);
4967 inode = ERR_PTR(ret);
4974 static int btrfs_dentry_delete(const struct dentry *dentry)
4976 struct btrfs_root *root;
4977 struct inode *inode = dentry->d_inode;
4979 if (!inode && !IS_ROOT(dentry))
4980 inode = dentry->d_parent->d_inode;
4983 root = BTRFS_I(inode)->root;
4984 if (btrfs_root_refs(&root->root_item) == 0)
4987 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
4993 static void btrfs_dentry_release(struct dentry *dentry)
4995 if (dentry->d_fsdata)
4996 kfree(dentry->d_fsdata);
4999 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5004 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
5008 unsigned char btrfs_filetype_table[] = {
5009 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5012 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5014 struct inode *inode = file_inode(file);
5015 struct btrfs_root *root = BTRFS_I(inode)->root;
5016 struct btrfs_item *item;
5017 struct btrfs_dir_item *di;
5018 struct btrfs_key key;
5019 struct btrfs_key found_key;
5020 struct btrfs_path *path;
5021 struct list_head ins_list;
5022 struct list_head del_list;
5024 struct extent_buffer *leaf;
5026 unsigned char d_type;
5031 int key_type = BTRFS_DIR_INDEX_KEY;
5035 int is_curr = 0; /* ctx->pos points to the current index? */
5037 /* FIXME, use a real flag for deciding about the key type */
5038 if (root->fs_info->tree_root == root)
5039 key_type = BTRFS_DIR_ITEM_KEY;
5041 if (!dir_emit_dots(file, ctx))
5044 path = btrfs_alloc_path();
5050 if (key_type == BTRFS_DIR_INDEX_KEY) {
5051 INIT_LIST_HEAD(&ins_list);
5052 INIT_LIST_HEAD(&del_list);
5053 btrfs_get_delayed_items(inode, &ins_list, &del_list);
5056 btrfs_set_key_type(&key, key_type);
5057 key.offset = ctx->pos;
5058 key.objectid = btrfs_ino(inode);
5060 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5065 leaf = path->nodes[0];
5066 slot = path->slots[0];
5067 if (slot >= btrfs_header_nritems(leaf)) {
5068 ret = btrfs_next_leaf(root, path);
5076 item = btrfs_item_nr(slot);
5077 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5079 if (found_key.objectid != key.objectid)
5081 if (btrfs_key_type(&found_key) != key_type)
5083 if (found_key.offset < ctx->pos)
5085 if (key_type == BTRFS_DIR_INDEX_KEY &&
5086 btrfs_should_delete_dir_index(&del_list,
5090 ctx->pos = found_key.offset;
5093 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5095 di_total = btrfs_item_size(leaf, item);
5097 while (di_cur < di_total) {
5098 struct btrfs_key location;
5100 if (verify_dir_item(root, leaf, di))
5103 name_len = btrfs_dir_name_len(leaf, di);
5104 if (name_len <= sizeof(tmp_name)) {
5105 name_ptr = tmp_name;
5107 name_ptr = kmalloc(name_len, GFP_NOFS);
5113 read_extent_buffer(leaf, name_ptr,
5114 (unsigned long)(di + 1), name_len);
5116 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
5117 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5120 /* is this a reference to our own snapshot? If so
5123 * In contrast to old kernels, we insert the snapshot's
5124 * dir item and dir index after it has been created, so
5125 * we won't find a reference to our own snapshot. We
5126 * still keep the following code for backward
5129 if (location.type == BTRFS_ROOT_ITEM_KEY &&
5130 location.objectid == root->root_key.objectid) {
5134 over = !dir_emit(ctx, name_ptr, name_len,
5135 location.objectid, d_type);
5138 if (name_ptr != tmp_name)
5143 di_len = btrfs_dir_name_len(leaf, di) +
5144 btrfs_dir_data_len(leaf, di) + sizeof(*di);
5146 di = (struct btrfs_dir_item *)((char *)di + di_len);
5152 if (key_type == BTRFS_DIR_INDEX_KEY) {
5155 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5160 /* Reached end of directory/root. Bump pos past the last item. */
5164 * Stop new entries from being returned after we return the last
5167 * New directory entries are assigned a strictly increasing
5168 * offset. This means that new entries created during readdir
5169 * are *guaranteed* to be seen in the future by that readdir.
5170 * This has broken buggy programs which operate on names as
5171 * they're returned by readdir. Until we re-use freed offsets
5172 * we have this hack to stop new entries from being returned
5173 * under the assumption that they'll never reach this huge
5176 * This is being careful not to overflow 32bit loff_t unless the
5177 * last entry requires it because doing so has broken 32bit apps
5180 if (key_type == BTRFS_DIR_INDEX_KEY) {
5181 if (ctx->pos >= INT_MAX)
5182 ctx->pos = LLONG_MAX;
5189 if (key_type == BTRFS_DIR_INDEX_KEY)
5190 btrfs_put_delayed_items(&ins_list, &del_list);
5191 btrfs_free_path(path);
5195 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
5197 struct btrfs_root *root = BTRFS_I(inode)->root;
5198 struct btrfs_trans_handle *trans;
5200 bool nolock = false;
5202 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5205 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode))
5208 if (wbc->sync_mode == WB_SYNC_ALL) {
5210 trans = btrfs_join_transaction_nolock(root);
5212 trans = btrfs_join_transaction(root);
5214 return PTR_ERR(trans);
5215 ret = btrfs_commit_transaction(trans, root);
5221 * This is somewhat expensive, updating the tree every time the
5222 * inode changes. But, it is most likely to find the inode in cache.
5223 * FIXME, needs more benchmarking...there are no reasons other than performance
5224 * to keep or drop this code.
5226 static int btrfs_dirty_inode(struct inode *inode)
5228 struct btrfs_root *root = BTRFS_I(inode)->root;
5229 struct btrfs_trans_handle *trans;
5232 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5235 trans = btrfs_join_transaction(root);
5237 return PTR_ERR(trans);
5239 ret = btrfs_update_inode(trans, root, inode);
5240 if (ret && ret == -ENOSPC) {
5241 /* whoops, lets try again with the full transaction */
5242 btrfs_end_transaction(trans, root);
5243 trans = btrfs_start_transaction(root, 1);
5245 return PTR_ERR(trans);
5247 ret = btrfs_update_inode(trans, root, inode);
5249 btrfs_end_transaction(trans, root);
5250 if (BTRFS_I(inode)->delayed_node)
5251 btrfs_balance_delayed_items(root);
5257 * This is a copy of file_update_time. We need this so we can return error on
5258 * ENOSPC for updating the inode in the case of file write and mmap writes.
5260 static int btrfs_update_time(struct inode *inode, struct timespec *now,
5263 struct btrfs_root *root = BTRFS_I(inode)->root;
5265 if (btrfs_root_readonly(root))
5268 if (flags & S_VERSION)
5269 inode_inc_iversion(inode);
5270 if (flags & S_CTIME)
5271 inode->i_ctime = *now;
5272 if (flags & S_MTIME)
5273 inode->i_mtime = *now;
5274 if (flags & S_ATIME)
5275 inode->i_atime = *now;
5276 return btrfs_dirty_inode(inode);
5280 * find the highest existing sequence number in a directory
5281 * and then set the in-memory index_cnt variable to reflect
5282 * free sequence numbers
5284 static int btrfs_set_inode_index_count(struct inode *inode)
5286 struct btrfs_root *root = BTRFS_I(inode)->root;
5287 struct btrfs_key key, found_key;
5288 struct btrfs_path *path;
5289 struct extent_buffer *leaf;
5292 key.objectid = btrfs_ino(inode);
5293 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
5294 key.offset = (u64)-1;
5296 path = btrfs_alloc_path();
5300 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5303 /* FIXME: we should be able to handle this */
5309 * MAGIC NUMBER EXPLANATION:
5310 * since we search a directory based on f_pos we have to start at 2
5311 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5312 * else has to start at 2
5314 if (path->slots[0] == 0) {
5315 BTRFS_I(inode)->index_cnt = 2;
5321 leaf = path->nodes[0];
5322 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5324 if (found_key.objectid != btrfs_ino(inode) ||
5325 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
5326 BTRFS_I(inode)->index_cnt = 2;
5330 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
5332 btrfs_free_path(path);
5337 * helper to find a free sequence number in a given directory. This current
5338 * code is very simple, later versions will do smarter things in the btree
5340 int btrfs_set_inode_index(struct inode *dir, u64 *index)
5344 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
5345 ret = btrfs_inode_delayed_dir_index_count(dir);
5347 ret = btrfs_set_inode_index_count(dir);
5353 *index = BTRFS_I(dir)->index_cnt;
5354 BTRFS_I(dir)->index_cnt++;
5359 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5360 struct btrfs_root *root,
5362 const char *name, int name_len,
5363 u64 ref_objectid, u64 objectid,
5364 umode_t mode, u64 *index)
5366 struct inode *inode;
5367 struct btrfs_inode_item *inode_item;
5368 struct btrfs_key *location;
5369 struct btrfs_path *path;
5370 struct btrfs_inode_ref *ref;
5371 struct btrfs_key key[2];
5376 path = btrfs_alloc_path();
5378 return ERR_PTR(-ENOMEM);
5380 inode = new_inode(root->fs_info->sb);
5382 btrfs_free_path(path);
5383 return ERR_PTR(-ENOMEM);
5387 * we have to initialize this early, so we can reclaim the inode
5388 * number if we fail afterwards in this function.
5390 inode->i_ino = objectid;
5393 trace_btrfs_inode_request(dir);
5395 ret = btrfs_set_inode_index(dir, index);
5397 btrfs_free_path(path);
5399 return ERR_PTR(ret);
5403 * index_cnt is ignored for everything but a dir,
5404 * btrfs_get_inode_index_count has an explanation for the magic
5407 BTRFS_I(inode)->index_cnt = 2;
5408 BTRFS_I(inode)->root = root;
5409 BTRFS_I(inode)->generation = trans->transid;
5410 inode->i_generation = BTRFS_I(inode)->generation;
5413 * We could have gotten an inode number from somebody who was fsynced
5414 * and then removed in this same transaction, so let's just set full
5415 * sync since it will be a full sync anyway and this will blow away the
5416 * old info in the log.
5418 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5420 key[0].objectid = objectid;
5421 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
5425 * Start new inodes with an inode_ref. This is slightly more
5426 * efficient for small numbers of hard links since they will
5427 * be packed into one item. Extended refs will kick in if we
5428 * add more hard links than can fit in the ref item.
5430 key[1].objectid = objectid;
5431 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
5432 key[1].offset = ref_objectid;
5434 sizes[0] = sizeof(struct btrfs_inode_item);
5435 sizes[1] = name_len + sizeof(*ref);
5437 path->leave_spinning = 1;
5438 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
5442 inode_init_owner(inode, dir, mode);
5443 inode_set_bytes(inode, 0);
5444 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5445 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
5446 struct btrfs_inode_item);
5447 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
5448 sizeof(*inode_item));
5449 fill_inode_item(trans, path->nodes[0], inode_item, inode);
5451 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
5452 struct btrfs_inode_ref);
5453 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
5454 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
5455 ptr = (unsigned long)(ref + 1);
5456 write_extent_buffer(path->nodes[0], name, ptr, name_len);
5458 btrfs_mark_buffer_dirty(path->nodes[0]);
5459 btrfs_free_path(path);
5461 location = &BTRFS_I(inode)->location;
5462 location->objectid = objectid;
5463 location->offset = 0;
5464 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
5466 btrfs_inherit_iflags(inode, dir);
5468 if (S_ISREG(mode)) {
5469 if (btrfs_test_opt(root, NODATASUM))
5470 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
5471 if (btrfs_test_opt(root, NODATACOW))
5472 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
5473 BTRFS_INODE_NODATASUM;
5476 btrfs_insert_inode_hash(inode);
5477 inode_tree_add(inode);
5479 trace_btrfs_inode_new(inode);
5480 btrfs_set_inode_last_trans(trans, inode);
5482 btrfs_update_root_times(trans, root);
5487 BTRFS_I(dir)->index_cnt--;
5488 btrfs_free_path(path);
5490 return ERR_PTR(ret);
5493 static inline u8 btrfs_inode_type(struct inode *inode)
5495 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
5499 * utility function to add 'inode' into 'parent_inode' with
5500 * a give name and a given sequence number.
5501 * if 'add_backref' is true, also insert a backref from the
5502 * inode to the parent directory.
5504 int btrfs_add_link(struct btrfs_trans_handle *trans,
5505 struct inode *parent_inode, struct inode *inode,
5506 const char *name, int name_len, int add_backref, u64 index)
5509 struct btrfs_key key;
5510 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
5511 u64 ino = btrfs_ino(inode);
5512 u64 parent_ino = btrfs_ino(parent_inode);
5514 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5515 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
5518 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
5522 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5523 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
5524 key.objectid, root->root_key.objectid,
5525 parent_ino, index, name, name_len);
5526 } else if (add_backref) {
5527 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
5531 /* Nothing to clean up yet */
5535 ret = btrfs_insert_dir_item(trans, root, name, name_len,
5537 btrfs_inode_type(inode), index);
5538 if (ret == -EEXIST || ret == -EOVERFLOW)
5541 btrfs_abort_transaction(trans, root, ret);
5545 btrfs_i_size_write(parent_inode, parent_inode->i_size +
5547 inode_inc_iversion(parent_inode);
5548 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
5549 ret = btrfs_update_inode(trans, root, parent_inode);
5551 btrfs_abort_transaction(trans, root, ret);
5555 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5558 err = btrfs_del_root_ref(trans, root->fs_info->tree_root,
5559 key.objectid, root->root_key.objectid,
5560 parent_ino, &local_index, name, name_len);
5562 } else if (add_backref) {
5566 err = btrfs_del_inode_ref(trans, root, name, name_len,
5567 ino, parent_ino, &local_index);
5572 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
5573 struct inode *dir, struct dentry *dentry,
5574 struct inode *inode, int backref, u64 index)
5576 int err = btrfs_add_link(trans, dir, inode,
5577 dentry->d_name.name, dentry->d_name.len,
5584 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
5585 umode_t mode, dev_t rdev)
5587 struct btrfs_trans_handle *trans;
5588 struct btrfs_root *root = BTRFS_I(dir)->root;
5589 struct inode *inode = NULL;
5595 if (!new_valid_dev(rdev))
5599 * 2 for inode item and ref
5601 * 1 for xattr if selinux is on
5603 trans = btrfs_start_transaction(root, 5);
5605 return PTR_ERR(trans);
5607 err = btrfs_find_free_ino(root, &objectid);
5611 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5612 dentry->d_name.len, btrfs_ino(dir), objectid,
5614 if (IS_ERR(inode)) {
5615 err = PTR_ERR(inode);
5619 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5626 * If the active LSM wants to access the inode during
5627 * d_instantiate it needs these. Smack checks to see
5628 * if the filesystem supports xattrs by looking at the
5632 inode->i_op = &btrfs_special_inode_operations;
5633 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5637 init_special_inode(inode, inode->i_mode, rdev);
5638 btrfs_update_inode(trans, root, inode);
5639 d_instantiate(dentry, inode);
5642 btrfs_end_transaction(trans, root);
5643 btrfs_btree_balance_dirty(root);
5645 inode_dec_link_count(inode);
5651 static int btrfs_create(struct inode *dir, struct dentry *dentry,
5652 umode_t mode, bool excl)
5654 struct btrfs_trans_handle *trans;
5655 struct btrfs_root *root = BTRFS_I(dir)->root;
5656 struct inode *inode = NULL;
5657 int drop_inode_on_err = 0;
5663 * 2 for inode item and ref
5665 * 1 for xattr if selinux is on
5667 trans = btrfs_start_transaction(root, 5);
5669 return PTR_ERR(trans);
5671 err = btrfs_find_free_ino(root, &objectid);
5675 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5676 dentry->d_name.len, btrfs_ino(dir), objectid,
5678 if (IS_ERR(inode)) {
5679 err = PTR_ERR(inode);
5682 drop_inode_on_err = 1;
5684 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5688 err = btrfs_update_inode(trans, root, inode);
5693 * If the active LSM wants to access the inode during
5694 * d_instantiate it needs these. Smack checks to see
5695 * if the filesystem supports xattrs by looking at the
5698 inode->i_fop = &btrfs_file_operations;
5699 inode->i_op = &btrfs_file_inode_operations;
5701 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5705 inode->i_mapping->a_ops = &btrfs_aops;
5706 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5707 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5708 d_instantiate(dentry, inode);
5711 btrfs_end_transaction(trans, root);
5712 if (err && drop_inode_on_err) {
5713 inode_dec_link_count(inode);
5716 btrfs_btree_balance_dirty(root);
5720 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
5721 struct dentry *dentry)
5723 struct btrfs_trans_handle *trans;
5724 struct btrfs_root *root = BTRFS_I(dir)->root;
5725 struct inode *inode = old_dentry->d_inode;
5730 /* do not allow sys_link's with other subvols of the same device */
5731 if (root->objectid != BTRFS_I(inode)->root->objectid)
5734 if (inode->i_nlink >= BTRFS_LINK_MAX)
5737 err = btrfs_set_inode_index(dir, &index);
5742 * 2 items for inode and inode ref
5743 * 2 items for dir items
5744 * 1 item for parent inode
5746 trans = btrfs_start_transaction(root, 5);
5747 if (IS_ERR(trans)) {
5748 err = PTR_ERR(trans);
5753 inode_inc_iversion(inode);
5754 inode->i_ctime = CURRENT_TIME;
5756 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
5758 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
5763 struct dentry *parent = dentry->d_parent;
5764 err = btrfs_update_inode(trans, root, inode);
5767 d_instantiate(dentry, inode);
5768 btrfs_log_new_name(trans, inode, NULL, parent);
5771 btrfs_end_transaction(trans, root);
5774 inode_dec_link_count(inode);
5777 btrfs_btree_balance_dirty(root);
5781 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
5783 struct inode *inode = NULL;
5784 struct btrfs_trans_handle *trans;
5785 struct btrfs_root *root = BTRFS_I(dir)->root;
5787 int drop_on_err = 0;
5792 * 2 items for inode and ref
5793 * 2 items for dir items
5794 * 1 for xattr if selinux is on
5796 trans = btrfs_start_transaction(root, 5);
5798 return PTR_ERR(trans);
5800 err = btrfs_find_free_ino(root, &objectid);
5804 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5805 dentry->d_name.len, btrfs_ino(dir), objectid,
5806 S_IFDIR | mode, &index);
5807 if (IS_ERR(inode)) {
5808 err = PTR_ERR(inode);
5814 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5818 inode->i_op = &btrfs_dir_inode_operations;
5819 inode->i_fop = &btrfs_dir_file_operations;
5821 btrfs_i_size_write(inode, 0);
5822 err = btrfs_update_inode(trans, root, inode);
5826 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
5827 dentry->d_name.len, 0, index);
5831 d_instantiate(dentry, inode);
5835 btrfs_end_transaction(trans, root);
5838 btrfs_btree_balance_dirty(root);
5842 /* helper for btfs_get_extent. Given an existing extent in the tree,
5843 * and an extent that you want to insert, deal with overlap and insert
5844 * the new extent into the tree.
5846 static int merge_extent_mapping(struct extent_map_tree *em_tree,
5847 struct extent_map *existing,
5848 struct extent_map *em,
5849 u64 map_start, u64 map_len)
5853 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
5854 start_diff = map_start - em->start;
5855 em->start = map_start;
5857 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
5858 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
5859 em->block_start += start_diff;
5860 em->block_len -= start_diff;
5862 return add_extent_mapping(em_tree, em, 0);
5865 static noinline int uncompress_inline(struct btrfs_path *path,
5866 struct inode *inode, struct page *page,
5867 size_t pg_offset, u64 extent_offset,
5868 struct btrfs_file_extent_item *item)
5871 struct extent_buffer *leaf = path->nodes[0];
5874 unsigned long inline_size;
5878 WARN_ON(pg_offset != 0);
5879 compress_type = btrfs_file_extent_compression(leaf, item);
5880 max_size = btrfs_file_extent_ram_bytes(leaf, item);
5881 inline_size = btrfs_file_extent_inline_item_len(leaf,
5882 btrfs_item_nr(path->slots[0]));
5883 tmp = kmalloc(inline_size, GFP_NOFS);
5886 ptr = btrfs_file_extent_inline_start(item);
5888 read_extent_buffer(leaf, tmp, ptr, inline_size);
5890 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
5891 ret = btrfs_decompress(compress_type, tmp, page,
5892 extent_offset, inline_size, max_size);
5894 char *kaddr = kmap_atomic(page);
5895 unsigned long copy_size = min_t(u64,
5896 PAGE_CACHE_SIZE - pg_offset,
5897 max_size - extent_offset);
5898 memset(kaddr + pg_offset, 0, copy_size);
5899 kunmap_atomic(kaddr);
5906 * a bit scary, this does extent mapping from logical file offset to the disk.
5907 * the ugly parts come from merging extents from the disk with the in-ram
5908 * representation. This gets more complex because of the data=ordered code,
5909 * where the in-ram extents might be locked pending data=ordered completion.
5911 * This also copies inline extents directly into the page.
5914 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
5915 size_t pg_offset, u64 start, u64 len,
5921 u64 extent_start = 0;
5923 u64 objectid = btrfs_ino(inode);
5925 struct btrfs_path *path = NULL;
5926 struct btrfs_root *root = BTRFS_I(inode)->root;
5927 struct btrfs_file_extent_item *item;
5928 struct extent_buffer *leaf;
5929 struct btrfs_key found_key;
5930 struct extent_map *em = NULL;
5931 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5932 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5933 struct btrfs_trans_handle *trans = NULL;
5937 read_lock(&em_tree->lock);
5938 em = lookup_extent_mapping(em_tree, start, len);
5940 em->bdev = root->fs_info->fs_devices->latest_bdev;
5941 read_unlock(&em_tree->lock);
5944 if (em->start > start || em->start + em->len <= start)
5945 free_extent_map(em);
5946 else if (em->block_start == EXTENT_MAP_INLINE && page)
5947 free_extent_map(em);
5951 em = alloc_extent_map();
5956 em->bdev = root->fs_info->fs_devices->latest_bdev;
5957 em->start = EXTENT_MAP_HOLE;
5958 em->orig_start = EXTENT_MAP_HOLE;
5960 em->block_len = (u64)-1;
5963 path = btrfs_alloc_path();
5969 * Chances are we'll be called again, so go ahead and do
5975 ret = btrfs_lookup_file_extent(trans, root, path,
5976 objectid, start, trans != NULL);
5983 if (path->slots[0] == 0)
5988 leaf = path->nodes[0];
5989 item = btrfs_item_ptr(leaf, path->slots[0],
5990 struct btrfs_file_extent_item);
5991 /* are we inside the extent that was found? */
5992 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5993 found_type = btrfs_key_type(&found_key);
5994 if (found_key.objectid != objectid ||
5995 found_type != BTRFS_EXTENT_DATA_KEY) {
5997 * If we backup past the first extent we want to move forward
5998 * and see if there is an extent in front of us, otherwise we'll
5999 * say there is a hole for our whole search range which can
6006 found_type = btrfs_file_extent_type(leaf, item);
6007 extent_start = found_key.offset;
6008 compress_type = btrfs_file_extent_compression(leaf, item);
6009 if (found_type == BTRFS_FILE_EXTENT_REG ||
6010 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6011 extent_end = extent_start +
6012 btrfs_file_extent_num_bytes(leaf, item);
6013 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6015 size = btrfs_file_extent_inline_len(leaf, item);
6016 extent_end = ALIGN(extent_start + size, root->sectorsize);
6019 if (start >= extent_end) {
6021 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6022 ret = btrfs_next_leaf(root, path);
6029 leaf = path->nodes[0];
6031 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6032 if (found_key.objectid != objectid ||
6033 found_key.type != BTRFS_EXTENT_DATA_KEY)
6035 if (start + len <= found_key.offset)
6038 em->orig_start = start;
6039 em->len = found_key.offset - start;
6043 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, item);
6044 if (found_type == BTRFS_FILE_EXTENT_REG ||
6045 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6046 em->start = extent_start;
6047 em->len = extent_end - extent_start;
6048 em->orig_start = extent_start -
6049 btrfs_file_extent_offset(leaf, item);
6050 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
6052 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
6054 em->block_start = EXTENT_MAP_HOLE;
6057 if (compress_type != BTRFS_COMPRESS_NONE) {
6058 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6059 em->compress_type = compress_type;
6060 em->block_start = bytenr;
6061 em->block_len = em->orig_block_len;
6063 bytenr += btrfs_file_extent_offset(leaf, item);
6064 em->block_start = bytenr;
6065 em->block_len = em->len;
6066 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
6067 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6070 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6074 size_t extent_offset;
6077 em->block_start = EXTENT_MAP_INLINE;
6078 if (!page || create) {
6079 em->start = extent_start;
6080 em->len = extent_end - extent_start;
6084 size = btrfs_file_extent_inline_len(leaf, item);
6085 extent_offset = page_offset(page) + pg_offset - extent_start;
6086 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
6087 size - extent_offset);
6088 em->start = extent_start + extent_offset;
6089 em->len = ALIGN(copy_size, root->sectorsize);
6090 em->orig_block_len = em->len;
6091 em->orig_start = em->start;
6092 if (compress_type) {
6093 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6094 em->compress_type = compress_type;
6096 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6097 if (create == 0 && !PageUptodate(page)) {
6098 if (btrfs_file_extent_compression(leaf, item) !=
6099 BTRFS_COMPRESS_NONE) {
6100 ret = uncompress_inline(path, inode, page,
6102 extent_offset, item);
6103 BUG_ON(ret); /* -ENOMEM */
6106 read_extent_buffer(leaf, map + pg_offset, ptr,
6108 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
6109 memset(map + pg_offset + copy_size, 0,
6110 PAGE_CACHE_SIZE - pg_offset -
6115 flush_dcache_page(page);
6116 } else if (create && PageUptodate(page)) {
6120 free_extent_map(em);
6123 btrfs_release_path(path);
6124 trans = btrfs_join_transaction(root);
6127 return ERR_CAST(trans);
6131 write_extent_buffer(leaf, map + pg_offset, ptr,
6134 btrfs_mark_buffer_dirty(leaf);
6136 set_extent_uptodate(io_tree, em->start,
6137 extent_map_end(em) - 1, NULL, GFP_NOFS);
6140 WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
6144 em->orig_start = start;
6147 em->block_start = EXTENT_MAP_HOLE;
6148 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
6150 btrfs_release_path(path);
6151 if (em->start > start || extent_map_end(em) <= start) {
6152 btrfs_err(root->fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]",
6153 em->start, em->len, start, len);
6159 write_lock(&em_tree->lock);
6160 ret = add_extent_mapping(em_tree, em, 0);
6161 /* it is possible that someone inserted the extent into the tree
6162 * while we had the lock dropped. It is also possible that
6163 * an overlapping map exists in the tree
6165 if (ret == -EEXIST) {
6166 struct extent_map *existing;
6170 existing = lookup_extent_mapping(em_tree, start, len);
6171 if (existing && (existing->start > start ||
6172 existing->start + existing->len <= start)) {
6173 free_extent_map(existing);
6177 existing = lookup_extent_mapping(em_tree, em->start,
6180 err = merge_extent_mapping(em_tree, existing,
6183 free_extent_map(existing);
6185 free_extent_map(em);
6190 free_extent_map(em);
6194 free_extent_map(em);
6199 write_unlock(&em_tree->lock);
6202 trace_btrfs_get_extent(root, em);
6205 btrfs_free_path(path);
6207 ret = btrfs_end_transaction(trans, root);
6212 free_extent_map(em);
6213 return ERR_PTR(err);
6215 BUG_ON(!em); /* Error is always set */
6219 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
6220 size_t pg_offset, u64 start, u64 len,
6223 struct extent_map *em;
6224 struct extent_map *hole_em = NULL;
6225 u64 range_start = start;
6231 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6238 * - a pre-alloc extent,
6239 * there might actually be delalloc bytes behind it.
6241 if (em->block_start != EXTENT_MAP_HOLE &&
6242 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6248 /* check to see if we've wrapped (len == -1 or similar) */
6257 /* ok, we didn't find anything, lets look for delalloc */
6258 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
6259 end, len, EXTENT_DELALLOC, 1);
6260 found_end = range_start + found;
6261 if (found_end < range_start)
6262 found_end = (u64)-1;
6265 * we didn't find anything useful, return
6266 * the original results from get_extent()
6268 if (range_start > end || found_end <= start) {
6274 /* adjust the range_start to make sure it doesn't
6275 * go backwards from the start they passed in
6277 range_start = max(start, range_start);
6278 found = found_end - range_start;
6281 u64 hole_start = start;
6284 em = alloc_extent_map();
6290 * when btrfs_get_extent can't find anything it
6291 * returns one huge hole
6293 * make sure what it found really fits our range, and
6294 * adjust to make sure it is based on the start from
6298 u64 calc_end = extent_map_end(hole_em);
6300 if (calc_end <= start || (hole_em->start > end)) {
6301 free_extent_map(hole_em);
6304 hole_start = max(hole_em->start, start);
6305 hole_len = calc_end - hole_start;
6309 if (hole_em && range_start > hole_start) {
6310 /* our hole starts before our delalloc, so we
6311 * have to return just the parts of the hole
6312 * that go until the delalloc starts
6314 em->len = min(hole_len,
6315 range_start - hole_start);
6316 em->start = hole_start;
6317 em->orig_start = hole_start;
6319 * don't adjust block start at all,
6320 * it is fixed at EXTENT_MAP_HOLE
6322 em->block_start = hole_em->block_start;
6323 em->block_len = hole_len;
6324 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6325 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6327 em->start = range_start;
6329 em->orig_start = range_start;
6330 em->block_start = EXTENT_MAP_DELALLOC;
6331 em->block_len = found;
6333 } else if (hole_em) {
6338 free_extent_map(hole_em);
6340 free_extent_map(em);
6341 return ERR_PTR(err);
6346 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6349 struct btrfs_root *root = BTRFS_I(inode)->root;
6350 struct extent_map *em;
6351 struct btrfs_key ins;
6355 alloc_hint = get_extent_allocation_hint(inode, start, len);
6356 ret = btrfs_reserve_extent(root, len, root->sectorsize, 0,
6357 alloc_hint, &ins, 1);
6359 return ERR_PTR(ret);
6361 em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
6362 ins.offset, ins.offset, ins.offset, 0);
6364 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6368 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
6369 ins.offset, ins.offset, 0);
6371 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6372 free_extent_map(em);
6373 return ERR_PTR(ret);
6380 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6381 * block must be cow'd
6383 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
6384 u64 *orig_start, u64 *orig_block_len,
6387 struct btrfs_trans_handle *trans;
6388 struct btrfs_path *path;
6390 struct extent_buffer *leaf;
6391 struct btrfs_root *root = BTRFS_I(inode)->root;
6392 struct btrfs_file_extent_item *fi;
6393 struct btrfs_key key;
6400 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
6401 path = btrfs_alloc_path();
6405 ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(inode),
6410 slot = path->slots[0];
6413 /* can't find the item, must cow */
6420 leaf = path->nodes[0];
6421 btrfs_item_key_to_cpu(leaf, &key, slot);
6422 if (key.objectid != btrfs_ino(inode) ||
6423 key.type != BTRFS_EXTENT_DATA_KEY) {
6424 /* not our file or wrong item type, must cow */
6428 if (key.offset > offset) {
6429 /* Wrong offset, must cow */
6433 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6434 found_type = btrfs_file_extent_type(leaf, fi);
6435 if (found_type != BTRFS_FILE_EXTENT_REG &&
6436 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6437 /* not a regular extent, must cow */
6441 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
6444 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6445 if (disk_bytenr == 0)
6448 if (btrfs_file_extent_compression(leaf, fi) ||
6449 btrfs_file_extent_encryption(leaf, fi) ||
6450 btrfs_file_extent_other_encoding(leaf, fi))
6453 backref_offset = btrfs_file_extent_offset(leaf, fi);
6456 *orig_start = key.offset - backref_offset;
6457 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
6458 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6461 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6463 if (btrfs_extent_readonly(root, disk_bytenr))
6465 btrfs_release_path(path);
6468 * look for other files referencing this extent, if we
6469 * find any we must cow
6471 trans = btrfs_join_transaction(root);
6472 if (IS_ERR(trans)) {
6477 ret = btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
6478 key.offset - backref_offset, disk_bytenr);
6479 btrfs_end_transaction(trans, root);
6486 * adjust disk_bytenr and num_bytes to cover just the bytes
6487 * in this extent we are about to write. If there
6488 * are any csums in that range we have to cow in order
6489 * to keep the csums correct
6491 disk_bytenr += backref_offset;
6492 disk_bytenr += offset - key.offset;
6493 num_bytes = min(offset + *len, extent_end) - offset;
6494 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
6497 * all of the above have passed, it is safe to overwrite this extent
6503 btrfs_free_path(path);
6507 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
6508 struct extent_state **cached_state, int writing)
6510 struct btrfs_ordered_extent *ordered;
6514 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6517 * We're concerned with the entire range that we're going to be
6518 * doing DIO to, so we need to make sure theres no ordered
6519 * extents in this range.
6521 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6522 lockend - lockstart + 1);
6525 * We need to make sure there are no buffered pages in this
6526 * range either, we could have raced between the invalidate in
6527 * generic_file_direct_write and locking the extent. The
6528 * invalidate needs to happen so that reads after a write do not
6531 if (!ordered && (!writing ||
6532 !test_range_bit(&BTRFS_I(inode)->io_tree,
6533 lockstart, lockend, EXTENT_UPTODATE, 0,
6537 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6538 cached_state, GFP_NOFS);
6541 btrfs_start_ordered_extent(inode, ordered, 1);
6542 btrfs_put_ordered_extent(ordered);
6544 /* Screw you mmap */
6545 ret = filemap_write_and_wait_range(inode->i_mapping,
6552 * If we found a page that couldn't be invalidated just
6553 * fall back to buffered.
6555 ret = invalidate_inode_pages2_range(inode->i_mapping,
6556 lockstart >> PAGE_CACHE_SHIFT,
6557 lockend >> PAGE_CACHE_SHIFT);
6568 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
6569 u64 len, u64 orig_start,
6570 u64 block_start, u64 block_len,
6571 u64 orig_block_len, u64 ram_bytes,
6574 struct extent_map_tree *em_tree;
6575 struct extent_map *em;
6576 struct btrfs_root *root = BTRFS_I(inode)->root;
6579 em_tree = &BTRFS_I(inode)->extent_tree;
6580 em = alloc_extent_map();
6582 return ERR_PTR(-ENOMEM);
6585 em->orig_start = orig_start;
6586 em->mod_start = start;
6589 em->block_len = block_len;
6590 em->block_start = block_start;
6591 em->bdev = root->fs_info->fs_devices->latest_bdev;
6592 em->orig_block_len = orig_block_len;
6593 em->ram_bytes = ram_bytes;
6594 em->generation = -1;
6595 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6596 if (type == BTRFS_ORDERED_PREALLOC)
6597 set_bit(EXTENT_FLAG_FILLING, &em->flags);
6600 btrfs_drop_extent_cache(inode, em->start,
6601 em->start + em->len - 1, 0);
6602 write_lock(&em_tree->lock);
6603 ret = add_extent_mapping(em_tree, em, 1);
6604 write_unlock(&em_tree->lock);
6605 } while (ret == -EEXIST);
6608 free_extent_map(em);
6609 return ERR_PTR(ret);
6616 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
6617 struct buffer_head *bh_result, int create)
6619 struct extent_map *em;
6620 struct btrfs_root *root = BTRFS_I(inode)->root;
6621 struct extent_state *cached_state = NULL;
6622 u64 start = iblock << inode->i_blkbits;
6623 u64 lockstart, lockend;
6624 u64 len = bh_result->b_size;
6625 int unlock_bits = EXTENT_LOCKED;
6629 unlock_bits |= EXTENT_DELALLOC | EXTENT_DIRTY;
6631 len = min_t(u64, len, root->sectorsize);
6634 lockend = start + len - 1;
6637 * If this errors out it's because we couldn't invalidate pagecache for
6638 * this range and we need to fallback to buffered.
6640 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create))
6643 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
6650 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
6651 * io. INLINE is special, and we could probably kludge it in here, but
6652 * it's still buffered so for safety lets just fall back to the generic
6655 * For COMPRESSED we _have_ to read the entire extent in so we can
6656 * decompress it, so there will be buffering required no matter what we
6657 * do, so go ahead and fallback to buffered.
6659 * We return -ENOTBLK because thats what makes DIO go ahead and go back
6660 * to buffered IO. Don't blame me, this is the price we pay for using
6663 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
6664 em->block_start == EXTENT_MAP_INLINE) {
6665 free_extent_map(em);
6670 /* Just a good old fashioned hole, return */
6671 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
6672 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
6673 free_extent_map(em);
6678 * We don't allocate a new extent in the following cases
6680 * 1) The inode is marked as NODATACOW. In this case we'll just use the
6682 * 2) The extent is marked as PREALLOC. We're good to go here and can
6683 * just use the extent.
6687 len = min(len, em->len - (start - em->start));
6688 lockstart = start + len;
6692 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
6693 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
6694 em->block_start != EXTENT_MAP_HOLE)) {
6697 u64 block_start, orig_start, orig_block_len, ram_bytes;
6699 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6700 type = BTRFS_ORDERED_PREALLOC;
6702 type = BTRFS_ORDERED_NOCOW;
6703 len = min(len, em->len - (start - em->start));
6704 block_start = em->block_start + (start - em->start);
6706 if (can_nocow_extent(inode, start, &len, &orig_start,
6707 &orig_block_len, &ram_bytes) == 1) {
6708 if (type == BTRFS_ORDERED_PREALLOC) {
6709 free_extent_map(em);
6710 em = create_pinned_em(inode, start, len,
6719 ret = btrfs_add_ordered_extent_dio(inode, start,
6720 block_start, len, len, type);
6722 free_extent_map(em);
6730 * this will cow the extent, reset the len in case we changed
6733 len = bh_result->b_size;
6734 free_extent_map(em);
6735 em = btrfs_new_extent_direct(inode, start, len);
6740 len = min(len, em->len - (start - em->start));
6742 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
6744 bh_result->b_size = len;
6745 bh_result->b_bdev = em->bdev;
6746 set_buffer_mapped(bh_result);
6748 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6749 set_buffer_new(bh_result);
6752 * Need to update the i_size under the extent lock so buffered
6753 * readers will get the updated i_size when we unlock.
6755 if (start + len > i_size_read(inode))
6756 i_size_write(inode, start + len);
6758 spin_lock(&BTRFS_I(inode)->lock);
6759 BTRFS_I(inode)->outstanding_extents++;
6760 spin_unlock(&BTRFS_I(inode)->lock);
6762 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6763 lockstart + len - 1, EXTENT_DELALLOC, NULL,
6764 &cached_state, GFP_NOFS);
6769 * In the case of write we need to clear and unlock the entire range,
6770 * in the case of read we need to unlock only the end area that we
6771 * aren't using if there is any left over space.
6773 if (lockstart < lockend) {
6774 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6775 lockend, unlock_bits, 1, 0,
6776 &cached_state, GFP_NOFS);
6778 free_extent_state(cached_state);
6781 free_extent_map(em);
6786 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6787 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
6791 static void btrfs_endio_direct_read(struct bio *bio, int err)
6793 struct btrfs_dio_private *dip = bio->bi_private;
6794 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
6795 struct bio_vec *bvec = bio->bi_io_vec;
6796 struct inode *inode = dip->inode;
6797 struct btrfs_root *root = BTRFS_I(inode)->root;
6798 struct bio *dio_bio;
6799 u32 *csums = (u32 *)dip->csum;
6803 start = dip->logical_offset;
6805 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
6806 struct page *page = bvec->bv_page;
6809 unsigned long flags;
6811 local_irq_save(flags);
6812 kaddr = kmap_atomic(page);
6813 csum = btrfs_csum_data(kaddr + bvec->bv_offset,
6814 csum, bvec->bv_len);
6815 btrfs_csum_final(csum, (char *)&csum);
6816 kunmap_atomic(kaddr);
6817 local_irq_restore(flags);
6819 flush_dcache_page(bvec->bv_page);
6820 if (csum != csums[index]) {
6821 btrfs_err(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
6822 btrfs_ino(inode), start, csum,
6828 start += bvec->bv_len;
6831 } while (bvec <= bvec_end);
6833 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
6834 dip->logical_offset + dip->bytes - 1);
6835 dio_bio = dip->dio_bio;
6839 /* If we had a csum failure make sure to clear the uptodate flag */
6841 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
6842 dio_end_io(dio_bio, err);
6846 static void btrfs_endio_direct_write(struct bio *bio, int err)
6848 struct btrfs_dio_private *dip = bio->bi_private;
6849 struct inode *inode = dip->inode;
6850 struct btrfs_root *root = BTRFS_I(inode)->root;
6851 struct btrfs_ordered_extent *ordered = NULL;
6852 u64 ordered_offset = dip->logical_offset;
6853 u64 ordered_bytes = dip->bytes;
6854 struct bio *dio_bio;
6860 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
6862 ordered_bytes, !err);
6866 ordered->work.func = finish_ordered_fn;
6867 ordered->work.flags = 0;
6868 btrfs_queue_worker(&root->fs_info->endio_write_workers,
6872 * our bio might span multiple ordered extents. If we haven't
6873 * completed the accounting for the whole dio, go back and try again
6875 if (ordered_offset < dip->logical_offset + dip->bytes) {
6876 ordered_bytes = dip->logical_offset + dip->bytes -
6882 dio_bio = dip->dio_bio;
6886 /* If we had an error make sure to clear the uptodate flag */
6888 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
6889 dio_end_io(dio_bio, err);
6893 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
6894 struct bio *bio, int mirror_num,
6895 unsigned long bio_flags, u64 offset)
6898 struct btrfs_root *root = BTRFS_I(inode)->root;
6899 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
6900 BUG_ON(ret); /* -ENOMEM */
6904 static void btrfs_end_dio_bio(struct bio *bio, int err)
6906 struct btrfs_dio_private *dip = bio->bi_private;
6909 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
6910 "sector %#Lx len %u err no %d\n",
6911 btrfs_ino(dip->inode), bio->bi_rw,
6912 (unsigned long long)bio->bi_sector, bio->bi_size, err);
6916 * before atomic variable goto zero, we must make sure
6917 * dip->errors is perceived to be set.
6919 smp_mb__before_atomic_dec();
6922 /* if there are more bios still pending for this dio, just exit */
6923 if (!atomic_dec_and_test(&dip->pending_bios))
6927 bio_io_error(dip->orig_bio);
6929 set_bit(BIO_UPTODATE, &dip->dio_bio->bi_flags);
6930 bio_endio(dip->orig_bio, 0);
6936 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
6937 u64 first_sector, gfp_t gfp_flags)
6939 int nr_vecs = bio_get_nr_vecs(bdev);
6940 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
6943 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
6944 int rw, u64 file_offset, int skip_sum,
6947 struct btrfs_dio_private *dip = bio->bi_private;
6948 int write = rw & REQ_WRITE;
6949 struct btrfs_root *root = BTRFS_I(inode)->root;
6953 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
6958 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
6966 if (write && async_submit) {
6967 ret = btrfs_wq_submit_bio(root->fs_info,
6968 inode, rw, bio, 0, 0,
6970 __btrfs_submit_bio_start_direct_io,
6971 __btrfs_submit_bio_done);
6975 * If we aren't doing async submit, calculate the csum of the
6978 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
6981 } else if (!skip_sum) {
6982 ret = btrfs_lookup_bio_sums_dio(root, inode, dip, bio,
6989 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
6995 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
6998 struct inode *inode = dip->inode;
6999 struct btrfs_root *root = BTRFS_I(inode)->root;
7001 struct bio *orig_bio = dip->orig_bio;
7002 struct bio_vec *bvec = orig_bio->bi_io_vec;
7003 u64 start_sector = orig_bio->bi_sector;
7004 u64 file_offset = dip->logical_offset;
7009 int async_submit = 0;
7011 map_length = orig_bio->bi_size;
7012 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9,
7013 &map_length, NULL, 0);
7019 if (map_length >= orig_bio->bi_size) {
7024 /* async crcs make it difficult to collect full stripe writes. */
7025 if (btrfs_get_alloc_profile(root, 1) &
7026 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
7031 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
7034 bio->bi_private = dip;
7035 bio->bi_end_io = btrfs_end_dio_bio;
7036 atomic_inc(&dip->pending_bios);
7038 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
7039 if (unlikely(map_length < submit_len + bvec->bv_len ||
7040 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
7041 bvec->bv_offset) < bvec->bv_len)) {
7043 * inc the count before we submit the bio so
7044 * we know the end IO handler won't happen before
7045 * we inc the count. Otherwise, the dip might get freed
7046 * before we're done setting it up
7048 atomic_inc(&dip->pending_bios);
7049 ret = __btrfs_submit_dio_bio(bio, inode, rw,
7050 file_offset, skip_sum,
7054 atomic_dec(&dip->pending_bios);
7058 start_sector += submit_len >> 9;
7059 file_offset += submit_len;
7064 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
7065 start_sector, GFP_NOFS);
7068 bio->bi_private = dip;
7069 bio->bi_end_io = btrfs_end_dio_bio;
7071 map_length = orig_bio->bi_size;
7072 ret = btrfs_map_block(root->fs_info, rw,
7074 &map_length, NULL, 0);
7080 submit_len += bvec->bv_len;
7087 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
7096 * before atomic variable goto zero, we must
7097 * make sure dip->errors is perceived to be set.
7099 smp_mb__before_atomic_dec();
7100 if (atomic_dec_and_test(&dip->pending_bios))
7101 bio_io_error(dip->orig_bio);
7103 /* bio_end_io() will handle error, so we needn't return it */
7107 static void btrfs_submit_direct(int rw, struct bio *dio_bio,
7108 struct inode *inode, loff_t file_offset)
7110 struct btrfs_root *root = BTRFS_I(inode)->root;
7111 struct btrfs_dio_private *dip;
7115 int write = rw & REQ_WRITE;
7119 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
7121 io_bio = btrfs_bio_clone(dio_bio, GFP_NOFS);
7127 if (!skip_sum && !write) {
7128 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
7129 sum_len = dio_bio->bi_size >> inode->i_sb->s_blocksize_bits;
7130 sum_len *= csum_size;
7135 dip = kmalloc(sizeof(*dip) + sum_len, GFP_NOFS);
7141 dip->private = dio_bio->bi_private;
7143 dip->logical_offset = file_offset;
7144 dip->bytes = dio_bio->bi_size;
7145 dip->disk_bytenr = (u64)dio_bio->bi_sector << 9;
7146 io_bio->bi_private = dip;
7148 dip->orig_bio = io_bio;
7149 dip->dio_bio = dio_bio;
7150 atomic_set(&dip->pending_bios, 0);
7153 io_bio->bi_end_io = btrfs_endio_direct_write;
7155 io_bio->bi_end_io = btrfs_endio_direct_read;
7157 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
7166 * If this is a write, we need to clean up the reserved space and kill
7167 * the ordered extent.
7170 struct btrfs_ordered_extent *ordered;
7171 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
7172 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
7173 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
7174 btrfs_free_reserved_extent(root, ordered->start,
7176 btrfs_put_ordered_extent(ordered);
7177 btrfs_put_ordered_extent(ordered);
7179 bio_endio(dio_bio, ret);
7182 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
7183 const struct iovec *iov, loff_t offset,
7184 unsigned long nr_segs)
7190 unsigned blocksize_mask = root->sectorsize - 1;
7191 ssize_t retval = -EINVAL;
7192 loff_t end = offset;
7194 if (offset & blocksize_mask)
7197 /* Check the memory alignment. Blocks cannot straddle pages */
7198 for (seg = 0; seg < nr_segs; seg++) {
7199 addr = (unsigned long)iov[seg].iov_base;
7200 size = iov[seg].iov_len;
7202 if ((addr & blocksize_mask) || (size & blocksize_mask))
7205 /* If this is a write we don't need to check anymore */
7210 * Check to make sure we don't have duplicate iov_base's in this
7211 * iovec, if so return EINVAL, otherwise we'll get csum errors
7212 * when reading back.
7214 for (i = seg + 1; i < nr_segs; i++) {
7215 if (iov[seg].iov_base == iov[i].iov_base)
7224 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
7225 const struct iovec *iov, loff_t offset,
7226 unsigned long nr_segs)
7228 struct file *file = iocb->ki_filp;
7229 struct inode *inode = file->f_mapping->host;
7233 bool relock = false;
7236 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
7240 atomic_inc(&inode->i_dio_count);
7241 smp_mb__after_atomic_inc();
7244 * The generic stuff only does filemap_write_and_wait_range, which isn't
7245 * enough if we've written compressed pages to this area, so we need to
7246 * call btrfs_wait_ordered_range to make absolutely sure that any
7247 * outstanding dirty pages are on disk.
7249 count = iov_length(iov, nr_segs);
7250 ret = btrfs_wait_ordered_range(inode, offset, count);
7256 * If the write DIO is beyond the EOF, we need update
7257 * the isize, but it is protected by i_mutex. So we can
7258 * not unlock the i_mutex at this case.
7260 if (offset + count <= inode->i_size) {
7261 mutex_unlock(&inode->i_mutex);
7264 ret = btrfs_delalloc_reserve_space(inode, count);
7267 } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7268 &BTRFS_I(inode)->runtime_flags))) {
7269 inode_dio_done(inode);
7270 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7274 ret = __blockdev_direct_IO(rw, iocb, inode,
7275 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
7276 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
7277 btrfs_submit_direct, flags);
7279 if (ret < 0 && ret != -EIOCBQUEUED)
7280 btrfs_delalloc_release_space(inode, count);
7281 else if (ret >= 0 && (size_t)ret < count)
7282 btrfs_delalloc_release_space(inode,
7283 count - (size_t)ret);
7285 btrfs_delalloc_release_metadata(inode, 0);
7289 inode_dio_done(inode);
7291 mutex_lock(&inode->i_mutex);
7296 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7298 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7299 __u64 start, __u64 len)
7303 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7307 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
7310 int btrfs_readpage(struct file *file, struct page *page)
7312 struct extent_io_tree *tree;
7313 tree = &BTRFS_I(page->mapping->host)->io_tree;
7314 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
7317 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
7319 struct extent_io_tree *tree;
7322 if (current->flags & PF_MEMALLOC) {
7323 redirty_page_for_writepage(wbc, page);
7327 tree = &BTRFS_I(page->mapping->host)->io_tree;
7328 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
7331 static int btrfs_writepages(struct address_space *mapping,
7332 struct writeback_control *wbc)
7334 struct extent_io_tree *tree;
7336 tree = &BTRFS_I(mapping->host)->io_tree;
7337 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
7341 btrfs_readpages(struct file *file, struct address_space *mapping,
7342 struct list_head *pages, unsigned nr_pages)
7344 struct extent_io_tree *tree;
7345 tree = &BTRFS_I(mapping->host)->io_tree;
7346 return extent_readpages(tree, mapping, pages, nr_pages,
7349 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7351 struct extent_io_tree *tree;
7352 struct extent_map_tree *map;
7355 tree = &BTRFS_I(page->mapping->host)->io_tree;
7356 map = &BTRFS_I(page->mapping->host)->extent_tree;
7357 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
7359 ClearPagePrivate(page);
7360 set_page_private(page, 0);
7361 page_cache_release(page);
7366 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7368 if (PageWriteback(page) || PageDirty(page))
7370 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
7373 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
7374 unsigned int length)
7376 struct inode *inode = page->mapping->host;
7377 struct extent_io_tree *tree;
7378 struct btrfs_ordered_extent *ordered;
7379 struct extent_state *cached_state = NULL;
7380 u64 page_start = page_offset(page);
7381 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
7384 * we have the page locked, so new writeback can't start,
7385 * and the dirty bit won't be cleared while we are here.
7387 * Wait for IO on this page so that we can safely clear
7388 * the PagePrivate2 bit and do ordered accounting
7390 wait_on_page_writeback(page);
7392 tree = &BTRFS_I(inode)->io_tree;
7394 btrfs_releasepage(page, GFP_NOFS);
7397 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7398 ordered = btrfs_lookup_ordered_extent(inode, page_offset(page));
7401 * IO on this page will never be started, so we need
7402 * to account for any ordered extents now
7404 clear_extent_bit(tree, page_start, page_end,
7405 EXTENT_DIRTY | EXTENT_DELALLOC |
7406 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
7407 EXTENT_DEFRAG, 1, 0, &cached_state, GFP_NOFS);
7409 * whoever cleared the private bit is responsible
7410 * for the finish_ordered_io
7412 if (TestClearPagePrivate2(page)) {
7413 struct btrfs_ordered_inode_tree *tree;
7416 tree = &BTRFS_I(inode)->ordered_tree;
7418 spin_lock_irq(&tree->lock);
7419 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
7420 new_len = page_start - ordered->file_offset;
7421 if (new_len < ordered->truncated_len)
7422 ordered->truncated_len = new_len;
7423 spin_unlock_irq(&tree->lock);
7425 if (btrfs_dec_test_ordered_pending(inode, &ordered,
7427 PAGE_CACHE_SIZE, 1))
7428 btrfs_finish_ordered_io(ordered);
7430 btrfs_put_ordered_extent(ordered);
7431 cached_state = NULL;
7432 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7434 clear_extent_bit(tree, page_start, page_end,
7435 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
7436 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
7437 &cached_state, GFP_NOFS);
7438 __btrfs_releasepage(page, GFP_NOFS);
7440 ClearPageChecked(page);
7441 if (PagePrivate(page)) {
7442 ClearPagePrivate(page);
7443 set_page_private(page, 0);
7444 page_cache_release(page);
7449 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
7450 * called from a page fault handler when a page is first dirtied. Hence we must
7451 * be careful to check for EOF conditions here. We set the page up correctly
7452 * for a written page which means we get ENOSPC checking when writing into
7453 * holes and correct delalloc and unwritten extent mapping on filesystems that
7454 * support these features.
7456 * We are not allowed to take the i_mutex here so we have to play games to
7457 * protect against truncate races as the page could now be beyond EOF. Because
7458 * vmtruncate() writes the inode size before removing pages, once we have the
7459 * page lock we can determine safely if the page is beyond EOF. If it is not
7460 * beyond EOF, then the page is guaranteed safe against truncation until we
7463 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
7465 struct page *page = vmf->page;
7466 struct inode *inode = file_inode(vma->vm_file);
7467 struct btrfs_root *root = BTRFS_I(inode)->root;
7468 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7469 struct btrfs_ordered_extent *ordered;
7470 struct extent_state *cached_state = NULL;
7472 unsigned long zero_start;
7479 sb_start_pagefault(inode->i_sb);
7480 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
7482 ret = file_update_time(vma->vm_file);
7488 else /* -ENOSPC, -EIO, etc */
7489 ret = VM_FAULT_SIGBUS;
7495 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
7498 size = i_size_read(inode);
7499 page_start = page_offset(page);
7500 page_end = page_start + PAGE_CACHE_SIZE - 1;
7502 if ((page->mapping != inode->i_mapping) ||
7503 (page_start >= size)) {
7504 /* page got truncated out from underneath us */
7507 wait_on_page_writeback(page);
7509 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
7510 set_page_extent_mapped(page);
7513 * we can't set the delalloc bits if there are pending ordered
7514 * extents. Drop our locks and wait for them to finish
7516 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7518 unlock_extent_cached(io_tree, page_start, page_end,
7519 &cached_state, GFP_NOFS);
7521 btrfs_start_ordered_extent(inode, ordered, 1);
7522 btrfs_put_ordered_extent(ordered);
7527 * XXX - page_mkwrite gets called every time the page is dirtied, even
7528 * if it was already dirty, so for space accounting reasons we need to
7529 * clear any delalloc bits for the range we are fixing to save. There
7530 * is probably a better way to do this, but for now keep consistent with
7531 * prepare_pages in the normal write path.
7533 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
7534 EXTENT_DIRTY | EXTENT_DELALLOC |
7535 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
7536 0, 0, &cached_state, GFP_NOFS);
7538 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
7541 unlock_extent_cached(io_tree, page_start, page_end,
7542 &cached_state, GFP_NOFS);
7543 ret = VM_FAULT_SIGBUS;
7548 /* page is wholly or partially inside EOF */
7549 if (page_start + PAGE_CACHE_SIZE > size)
7550 zero_start = size & ~PAGE_CACHE_MASK;
7552 zero_start = PAGE_CACHE_SIZE;
7554 if (zero_start != PAGE_CACHE_SIZE) {
7556 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
7557 flush_dcache_page(page);
7560 ClearPageChecked(page);
7561 set_page_dirty(page);
7562 SetPageUptodate(page);
7564 BTRFS_I(inode)->last_trans = root->fs_info->generation;
7565 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
7566 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
7568 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
7572 sb_end_pagefault(inode->i_sb);
7573 return VM_FAULT_LOCKED;
7577 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
7579 sb_end_pagefault(inode->i_sb);
7583 static int btrfs_truncate(struct inode *inode)
7585 struct btrfs_root *root = BTRFS_I(inode)->root;
7586 struct btrfs_block_rsv *rsv;
7589 struct btrfs_trans_handle *trans;
7590 u64 mask = root->sectorsize - 1;
7591 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
7593 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
7599 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
7600 * 3 things going on here
7602 * 1) We need to reserve space for our orphan item and the space to
7603 * delete our orphan item. Lord knows we don't want to have a dangling
7604 * orphan item because we didn't reserve space to remove it.
7606 * 2) We need to reserve space to update our inode.
7608 * 3) We need to have something to cache all the space that is going to
7609 * be free'd up by the truncate operation, but also have some slack
7610 * space reserved in case it uses space during the truncate (thank you
7611 * very much snapshotting).
7613 * And we need these to all be seperate. The fact is we can use alot of
7614 * space doing the truncate, and we have no earthly idea how much space
7615 * we will use, so we need the truncate reservation to be seperate so it
7616 * doesn't end up using space reserved for updating the inode or
7617 * removing the orphan item. We also need to be able to stop the
7618 * transaction and start a new one, which means we need to be able to
7619 * update the inode several times, and we have no idea of knowing how
7620 * many times that will be, so we can't just reserve 1 item for the
7621 * entirety of the opration, so that has to be done seperately as well.
7622 * Then there is the orphan item, which does indeed need to be held on
7623 * to for the whole operation, and we need nobody to touch this reserved
7624 * space except the orphan code.
7626 * So that leaves us with
7628 * 1) root->orphan_block_rsv - for the orphan deletion.
7629 * 2) rsv - for the truncate reservation, which we will steal from the
7630 * transaction reservation.
7631 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
7632 * updating the inode.
7634 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
7637 rsv->size = min_size;
7641 * 1 for the truncate slack space
7642 * 1 for updating the inode.
7644 trans = btrfs_start_transaction(root, 2);
7645 if (IS_ERR(trans)) {
7646 err = PTR_ERR(trans);
7650 /* Migrate the slack space for the truncate to our reserve */
7651 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
7656 * setattr is responsible for setting the ordered_data_close flag,
7657 * but that is only tested during the last file release. That
7658 * could happen well after the next commit, leaving a great big
7659 * window where new writes may get lost if someone chooses to write
7660 * to this file after truncating to zero
7662 * The inode doesn't have any dirty data here, and so if we commit
7663 * this is a noop. If someone immediately starts writing to the inode
7664 * it is very likely we'll catch some of their writes in this
7665 * transaction, and the commit will find this file on the ordered
7666 * data list with good things to send down.
7668 * This is a best effort solution, there is still a window where
7669 * using truncate to replace the contents of the file will
7670 * end up with a zero length file after a crash.
7672 if (inode->i_size == 0 && test_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
7673 &BTRFS_I(inode)->runtime_flags))
7674 btrfs_add_ordered_operation(trans, root, inode);
7677 * So if we truncate and then write and fsync we normally would just
7678 * write the extents that changed, which is a problem if we need to
7679 * first truncate that entire inode. So set this flag so we write out
7680 * all of the extents in the inode to the sync log so we're completely
7683 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
7684 trans->block_rsv = rsv;
7687 ret = btrfs_truncate_inode_items(trans, root, inode,
7689 BTRFS_EXTENT_DATA_KEY);
7690 if (ret != -ENOSPC) {
7695 trans->block_rsv = &root->fs_info->trans_block_rsv;
7696 ret = btrfs_update_inode(trans, root, inode);
7702 btrfs_end_transaction(trans, root);
7703 btrfs_btree_balance_dirty(root);
7705 trans = btrfs_start_transaction(root, 2);
7706 if (IS_ERR(trans)) {
7707 ret = err = PTR_ERR(trans);
7712 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
7714 BUG_ON(ret); /* shouldn't happen */
7715 trans->block_rsv = rsv;
7718 if (ret == 0 && inode->i_nlink > 0) {
7719 trans->block_rsv = root->orphan_block_rsv;
7720 ret = btrfs_orphan_del(trans, inode);
7726 trans->block_rsv = &root->fs_info->trans_block_rsv;
7727 ret = btrfs_update_inode(trans, root, inode);
7731 ret = btrfs_end_transaction(trans, root);
7732 btrfs_btree_balance_dirty(root);
7736 btrfs_free_block_rsv(root, rsv);
7745 * create a new subvolume directory/inode (helper for the ioctl).
7747 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
7748 struct btrfs_root *new_root, u64 new_dirid)
7750 struct inode *inode;
7754 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
7755 new_dirid, new_dirid,
7756 S_IFDIR | (~current_umask() & S_IRWXUGO),
7759 return PTR_ERR(inode);
7760 inode->i_op = &btrfs_dir_inode_operations;
7761 inode->i_fop = &btrfs_dir_file_operations;
7763 set_nlink(inode, 1);
7764 btrfs_i_size_write(inode, 0);
7766 err = btrfs_update_inode(trans, new_root, inode);
7772 struct inode *btrfs_alloc_inode(struct super_block *sb)
7774 struct btrfs_inode *ei;
7775 struct inode *inode;
7777 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
7784 ei->last_sub_trans = 0;
7785 ei->logged_trans = 0;
7786 ei->delalloc_bytes = 0;
7787 ei->disk_i_size = 0;
7790 ei->index_cnt = (u64)-1;
7791 ei->last_unlink_trans = 0;
7792 ei->last_log_commit = 0;
7794 spin_lock_init(&ei->lock);
7795 ei->outstanding_extents = 0;
7796 ei->reserved_extents = 0;
7798 ei->runtime_flags = 0;
7799 ei->force_compress = BTRFS_COMPRESS_NONE;
7801 ei->delayed_node = NULL;
7803 inode = &ei->vfs_inode;
7804 extent_map_tree_init(&ei->extent_tree);
7805 extent_io_tree_init(&ei->io_tree, &inode->i_data);
7806 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
7807 ei->io_tree.track_uptodate = 1;
7808 ei->io_failure_tree.track_uptodate = 1;
7809 atomic_set(&ei->sync_writers, 0);
7810 mutex_init(&ei->log_mutex);
7811 mutex_init(&ei->delalloc_mutex);
7812 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
7813 INIT_LIST_HEAD(&ei->delalloc_inodes);
7814 INIT_LIST_HEAD(&ei->ordered_operations);
7815 RB_CLEAR_NODE(&ei->rb_node);
7820 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
7821 void btrfs_test_destroy_inode(struct inode *inode)
7823 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
7824 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
7828 static void btrfs_i_callback(struct rcu_head *head)
7830 struct inode *inode = container_of(head, struct inode, i_rcu);
7831 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
7834 void btrfs_destroy_inode(struct inode *inode)
7836 struct btrfs_ordered_extent *ordered;
7837 struct btrfs_root *root = BTRFS_I(inode)->root;
7839 WARN_ON(!hlist_empty(&inode->i_dentry));
7840 WARN_ON(inode->i_data.nrpages);
7841 WARN_ON(BTRFS_I(inode)->outstanding_extents);
7842 WARN_ON(BTRFS_I(inode)->reserved_extents);
7843 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
7844 WARN_ON(BTRFS_I(inode)->csum_bytes);
7847 * This can happen where we create an inode, but somebody else also
7848 * created the same inode and we need to destroy the one we already
7855 * Make sure we're properly removed from the ordered operation
7859 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
7860 spin_lock(&root->fs_info->ordered_root_lock);
7861 list_del_init(&BTRFS_I(inode)->ordered_operations);
7862 spin_unlock(&root->fs_info->ordered_root_lock);
7865 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
7866 &BTRFS_I(inode)->runtime_flags)) {
7867 btrfs_info(root->fs_info, "inode %llu still on the orphan list",
7869 atomic_dec(&root->orphan_inodes);
7873 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
7877 btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup",
7878 ordered->file_offset, ordered->len);
7879 btrfs_remove_ordered_extent(inode, ordered);
7880 btrfs_put_ordered_extent(ordered);
7881 btrfs_put_ordered_extent(ordered);
7884 inode_tree_del(inode);
7885 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
7887 call_rcu(&inode->i_rcu, btrfs_i_callback);
7890 int btrfs_drop_inode(struct inode *inode)
7892 struct btrfs_root *root = BTRFS_I(inode)->root;
7897 /* the snap/subvol tree is on deleting */
7898 if (btrfs_root_refs(&root->root_item) == 0)
7901 return generic_drop_inode(inode);
7904 static void init_once(void *foo)
7906 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
7908 inode_init_once(&ei->vfs_inode);
7911 void btrfs_destroy_cachep(void)
7914 * Make sure all delayed rcu free inodes are flushed before we
7918 if (btrfs_inode_cachep)
7919 kmem_cache_destroy(btrfs_inode_cachep);
7920 if (btrfs_trans_handle_cachep)
7921 kmem_cache_destroy(btrfs_trans_handle_cachep);
7922 if (btrfs_transaction_cachep)
7923 kmem_cache_destroy(btrfs_transaction_cachep);
7924 if (btrfs_path_cachep)
7925 kmem_cache_destroy(btrfs_path_cachep);
7926 if (btrfs_free_space_cachep)
7927 kmem_cache_destroy(btrfs_free_space_cachep);
7928 if (btrfs_delalloc_work_cachep)
7929 kmem_cache_destroy(btrfs_delalloc_work_cachep);
7932 int btrfs_init_cachep(void)
7934 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
7935 sizeof(struct btrfs_inode), 0,
7936 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
7937 if (!btrfs_inode_cachep)
7940 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
7941 sizeof(struct btrfs_trans_handle), 0,
7942 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
7943 if (!btrfs_trans_handle_cachep)
7946 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
7947 sizeof(struct btrfs_transaction), 0,
7948 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
7949 if (!btrfs_transaction_cachep)
7952 btrfs_path_cachep = kmem_cache_create("btrfs_path",
7953 sizeof(struct btrfs_path), 0,
7954 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
7955 if (!btrfs_path_cachep)
7958 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
7959 sizeof(struct btrfs_free_space), 0,
7960 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
7961 if (!btrfs_free_space_cachep)
7964 btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
7965 sizeof(struct btrfs_delalloc_work), 0,
7966 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
7968 if (!btrfs_delalloc_work_cachep)
7973 btrfs_destroy_cachep();
7977 static int btrfs_getattr(struct vfsmount *mnt,
7978 struct dentry *dentry, struct kstat *stat)
7981 struct inode *inode = dentry->d_inode;
7982 u32 blocksize = inode->i_sb->s_blocksize;
7984 generic_fillattr(inode, stat);
7985 stat->dev = BTRFS_I(inode)->root->anon_dev;
7986 stat->blksize = PAGE_CACHE_SIZE;
7988 spin_lock(&BTRFS_I(inode)->lock);
7989 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
7990 spin_unlock(&BTRFS_I(inode)->lock);
7991 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
7992 ALIGN(delalloc_bytes, blocksize)) >> 9;
7996 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
7997 struct inode *new_dir, struct dentry *new_dentry)
7999 struct btrfs_trans_handle *trans;
8000 struct btrfs_root *root = BTRFS_I(old_dir)->root;
8001 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
8002 struct inode *new_inode = new_dentry->d_inode;
8003 struct inode *old_inode = old_dentry->d_inode;
8004 struct timespec ctime = CURRENT_TIME;
8008 u64 old_ino = btrfs_ino(old_inode);
8010 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
8013 /* we only allow rename subvolume link between subvolumes */
8014 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
8017 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
8018 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
8021 if (S_ISDIR(old_inode->i_mode) && new_inode &&
8022 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
8026 /* check for collisions, even if the name isn't there */
8027 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
8028 new_dentry->d_name.name,
8029 new_dentry->d_name.len);
8032 if (ret == -EEXIST) {
8034 * eexist without a new_inode */
8035 if (WARN_ON(!new_inode)) {
8039 /* maybe -EOVERFLOW */
8046 * we're using rename to replace one file with another.
8047 * and the replacement file is large. Start IO on it now so
8048 * we don't add too much work to the end of the transaction
8050 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
8051 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
8052 filemap_flush(old_inode->i_mapping);
8054 /* close the racy window with snapshot create/destroy ioctl */
8055 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8056 down_read(&root->fs_info->subvol_sem);
8058 * We want to reserve the absolute worst case amount of items. So if
8059 * both inodes are subvols and we need to unlink them then that would
8060 * require 4 item modifications, but if they are both normal inodes it
8061 * would require 5 item modifications, so we'll assume their normal
8062 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
8063 * should cover the worst case number of items we'll modify.
8065 trans = btrfs_start_transaction(root, 11);
8066 if (IS_ERR(trans)) {
8067 ret = PTR_ERR(trans);
8072 btrfs_record_root_in_trans(trans, dest);
8074 ret = btrfs_set_inode_index(new_dir, &index);
8078 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8079 /* force full log commit if subvolume involved. */
8080 root->fs_info->last_trans_log_full_commit = trans->transid;
8082 ret = btrfs_insert_inode_ref(trans, dest,
8083 new_dentry->d_name.name,
8084 new_dentry->d_name.len,
8086 btrfs_ino(new_dir), index);
8090 * this is an ugly little race, but the rename is required
8091 * to make sure that if we crash, the inode is either at the
8092 * old name or the new one. pinning the log transaction lets
8093 * us make sure we don't allow a log commit to come in after
8094 * we unlink the name but before we add the new name back in.
8096 btrfs_pin_log_trans(root);
8099 * make sure the inode gets flushed if it is replacing
8102 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
8103 btrfs_add_ordered_operation(trans, root, old_inode);
8105 inode_inc_iversion(old_dir);
8106 inode_inc_iversion(new_dir);
8107 inode_inc_iversion(old_inode);
8108 old_dir->i_ctime = old_dir->i_mtime = ctime;
8109 new_dir->i_ctime = new_dir->i_mtime = ctime;
8110 old_inode->i_ctime = ctime;
8112 if (old_dentry->d_parent != new_dentry->d_parent)
8113 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
8115 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8116 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
8117 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
8118 old_dentry->d_name.name,
8119 old_dentry->d_name.len);
8121 ret = __btrfs_unlink_inode(trans, root, old_dir,
8122 old_dentry->d_inode,
8123 old_dentry->d_name.name,
8124 old_dentry->d_name.len);
8126 ret = btrfs_update_inode(trans, root, old_inode);
8129 btrfs_abort_transaction(trans, root, ret);
8134 inode_inc_iversion(new_inode);
8135 new_inode->i_ctime = CURRENT_TIME;
8136 if (unlikely(btrfs_ino(new_inode) ==
8137 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
8138 root_objectid = BTRFS_I(new_inode)->location.objectid;
8139 ret = btrfs_unlink_subvol(trans, dest, new_dir,
8141 new_dentry->d_name.name,
8142 new_dentry->d_name.len);
8143 BUG_ON(new_inode->i_nlink == 0);
8145 ret = btrfs_unlink_inode(trans, dest, new_dir,
8146 new_dentry->d_inode,
8147 new_dentry->d_name.name,
8148 new_dentry->d_name.len);
8150 if (!ret && new_inode->i_nlink == 0)
8151 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
8153 btrfs_abort_transaction(trans, root, ret);
8158 ret = btrfs_add_link(trans, new_dir, old_inode,
8159 new_dentry->d_name.name,
8160 new_dentry->d_name.len, 0, index);
8162 btrfs_abort_transaction(trans, root, ret);
8166 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
8167 struct dentry *parent = new_dentry->d_parent;
8168 btrfs_log_new_name(trans, old_inode, old_dir, parent);
8169 btrfs_end_log_trans(root);
8172 btrfs_end_transaction(trans, root);
8174 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8175 up_read(&root->fs_info->subvol_sem);
8180 static void btrfs_run_delalloc_work(struct btrfs_work *work)
8182 struct btrfs_delalloc_work *delalloc_work;
8183 struct inode *inode;
8185 delalloc_work = container_of(work, struct btrfs_delalloc_work,
8187 inode = delalloc_work->inode;
8188 if (delalloc_work->wait) {
8189 btrfs_wait_ordered_range(inode, 0, (u64)-1);
8191 filemap_flush(inode->i_mapping);
8192 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
8193 &BTRFS_I(inode)->runtime_flags))
8194 filemap_flush(inode->i_mapping);
8197 if (delalloc_work->delay_iput)
8198 btrfs_add_delayed_iput(inode);
8201 complete(&delalloc_work->completion);
8204 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
8205 int wait, int delay_iput)
8207 struct btrfs_delalloc_work *work;
8209 work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
8213 init_completion(&work->completion);
8214 INIT_LIST_HEAD(&work->list);
8215 work->inode = inode;
8217 work->delay_iput = delay_iput;
8218 work->work.func = btrfs_run_delalloc_work;
8223 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
8225 wait_for_completion(&work->completion);
8226 kmem_cache_free(btrfs_delalloc_work_cachep, work);
8230 * some fairly slow code that needs optimization. This walks the list
8231 * of all the inodes with pending delalloc and forces them to disk.
8233 static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8235 struct btrfs_inode *binode;
8236 struct inode *inode;
8237 struct btrfs_delalloc_work *work, *next;
8238 struct list_head works;
8239 struct list_head splice;
8242 INIT_LIST_HEAD(&works);
8243 INIT_LIST_HEAD(&splice);
8245 spin_lock(&root->delalloc_lock);
8246 list_splice_init(&root->delalloc_inodes, &splice);
8247 while (!list_empty(&splice)) {
8248 binode = list_entry(splice.next, struct btrfs_inode,
8251 list_move_tail(&binode->delalloc_inodes,
8252 &root->delalloc_inodes);
8253 inode = igrab(&binode->vfs_inode);
8255 cond_resched_lock(&root->delalloc_lock);
8258 spin_unlock(&root->delalloc_lock);
8260 work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
8261 if (unlikely(!work)) {
8263 btrfs_add_delayed_iput(inode);
8269 list_add_tail(&work->list, &works);
8270 btrfs_queue_worker(&root->fs_info->flush_workers,
8274 spin_lock(&root->delalloc_lock);
8276 spin_unlock(&root->delalloc_lock);
8278 list_for_each_entry_safe(work, next, &works, list) {
8279 list_del_init(&work->list);
8280 btrfs_wait_and_free_delalloc_work(work);
8284 list_for_each_entry_safe(work, next, &works, list) {
8285 list_del_init(&work->list);
8286 btrfs_wait_and_free_delalloc_work(work);
8289 if (!list_empty_careful(&splice)) {
8290 spin_lock(&root->delalloc_lock);
8291 list_splice_tail(&splice, &root->delalloc_inodes);
8292 spin_unlock(&root->delalloc_lock);
8297 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8301 if (root->fs_info->sb->s_flags & MS_RDONLY)
8304 ret = __start_delalloc_inodes(root, delay_iput);
8306 * the filemap_flush will queue IO into the worker threads, but
8307 * we have to make sure the IO is actually started and that
8308 * ordered extents get created before we return
8310 atomic_inc(&root->fs_info->async_submit_draining);
8311 while (atomic_read(&root->fs_info->nr_async_submits) ||
8312 atomic_read(&root->fs_info->async_delalloc_pages)) {
8313 wait_event(root->fs_info->async_submit_wait,
8314 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
8315 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
8317 atomic_dec(&root->fs_info->async_submit_draining);
8321 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput)
8323 struct btrfs_root *root;
8324 struct list_head splice;
8327 if (fs_info->sb->s_flags & MS_RDONLY)
8330 INIT_LIST_HEAD(&splice);
8332 spin_lock(&fs_info->delalloc_root_lock);
8333 list_splice_init(&fs_info->delalloc_roots, &splice);
8334 while (!list_empty(&splice)) {
8335 root = list_first_entry(&splice, struct btrfs_root,
8337 root = btrfs_grab_fs_root(root);
8339 list_move_tail(&root->delalloc_root,
8340 &fs_info->delalloc_roots);
8341 spin_unlock(&fs_info->delalloc_root_lock);
8343 ret = __start_delalloc_inodes(root, delay_iput);
8344 btrfs_put_fs_root(root);
8348 spin_lock(&fs_info->delalloc_root_lock);
8350 spin_unlock(&fs_info->delalloc_root_lock);
8352 atomic_inc(&fs_info->async_submit_draining);
8353 while (atomic_read(&fs_info->nr_async_submits) ||
8354 atomic_read(&fs_info->async_delalloc_pages)) {
8355 wait_event(fs_info->async_submit_wait,
8356 (atomic_read(&fs_info->nr_async_submits) == 0 &&
8357 atomic_read(&fs_info->async_delalloc_pages) == 0));
8359 atomic_dec(&fs_info->async_submit_draining);
8362 if (!list_empty_careful(&splice)) {
8363 spin_lock(&fs_info->delalloc_root_lock);
8364 list_splice_tail(&splice, &fs_info->delalloc_roots);
8365 spin_unlock(&fs_info->delalloc_root_lock);
8370 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
8371 const char *symname)
8373 struct btrfs_trans_handle *trans;
8374 struct btrfs_root *root = BTRFS_I(dir)->root;
8375 struct btrfs_path *path;
8376 struct btrfs_key key;
8377 struct inode *inode = NULL;
8385 struct btrfs_file_extent_item *ei;
8386 struct extent_buffer *leaf;
8388 name_len = strlen(symname);
8389 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
8390 return -ENAMETOOLONG;
8393 * 2 items for inode item and ref
8394 * 2 items for dir items
8395 * 1 item for xattr if selinux is on
8397 trans = btrfs_start_transaction(root, 5);
8399 return PTR_ERR(trans);
8401 err = btrfs_find_free_ino(root, &objectid);
8405 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
8406 dentry->d_name.len, btrfs_ino(dir), objectid,
8407 S_IFLNK|S_IRWXUGO, &index);
8408 if (IS_ERR(inode)) {
8409 err = PTR_ERR(inode);
8413 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
8420 * If the active LSM wants to access the inode during
8421 * d_instantiate it needs these. Smack checks to see
8422 * if the filesystem supports xattrs by looking at the
8425 inode->i_fop = &btrfs_file_operations;
8426 inode->i_op = &btrfs_file_inode_operations;
8428 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
8432 inode->i_mapping->a_ops = &btrfs_aops;
8433 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8434 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
8439 path = btrfs_alloc_path();
8445 key.objectid = btrfs_ino(inode);
8447 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
8448 datasize = btrfs_file_extent_calc_inline_size(name_len);
8449 err = btrfs_insert_empty_item(trans, root, path, &key,
8453 btrfs_free_path(path);
8456 leaf = path->nodes[0];
8457 ei = btrfs_item_ptr(leaf, path->slots[0],
8458 struct btrfs_file_extent_item);
8459 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
8460 btrfs_set_file_extent_type(leaf, ei,
8461 BTRFS_FILE_EXTENT_INLINE);
8462 btrfs_set_file_extent_encryption(leaf, ei, 0);
8463 btrfs_set_file_extent_compression(leaf, ei, 0);
8464 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
8465 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
8467 ptr = btrfs_file_extent_inline_start(ei);
8468 write_extent_buffer(leaf, symname, ptr, name_len);
8469 btrfs_mark_buffer_dirty(leaf);
8470 btrfs_free_path(path);
8472 inode->i_op = &btrfs_symlink_inode_operations;
8473 inode->i_mapping->a_ops = &btrfs_symlink_aops;
8474 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8475 inode_set_bytes(inode, name_len);
8476 btrfs_i_size_write(inode, name_len);
8477 err = btrfs_update_inode(trans, root, inode);
8483 d_instantiate(dentry, inode);
8484 btrfs_end_transaction(trans, root);
8486 inode_dec_link_count(inode);
8489 btrfs_btree_balance_dirty(root);
8493 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
8494 u64 start, u64 num_bytes, u64 min_size,
8495 loff_t actual_len, u64 *alloc_hint,
8496 struct btrfs_trans_handle *trans)
8498 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
8499 struct extent_map *em;
8500 struct btrfs_root *root = BTRFS_I(inode)->root;
8501 struct btrfs_key ins;
8502 u64 cur_offset = start;
8506 bool own_trans = true;
8510 while (num_bytes > 0) {
8512 trans = btrfs_start_transaction(root, 3);
8513 if (IS_ERR(trans)) {
8514 ret = PTR_ERR(trans);
8519 cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
8520 cur_bytes = max(cur_bytes, min_size);
8521 ret = btrfs_reserve_extent(root, cur_bytes, min_size, 0,
8522 *alloc_hint, &ins, 1);
8525 btrfs_end_transaction(trans, root);
8529 ret = insert_reserved_file_extent(trans, inode,
8530 cur_offset, ins.objectid,
8531 ins.offset, ins.offset,
8532 ins.offset, 0, 0, 0,
8533 BTRFS_FILE_EXTENT_PREALLOC);
8535 btrfs_free_reserved_extent(root, ins.objectid,
8537 btrfs_abort_transaction(trans, root, ret);
8539 btrfs_end_transaction(trans, root);
8542 btrfs_drop_extent_cache(inode, cur_offset,
8543 cur_offset + ins.offset -1, 0);
8545 em = alloc_extent_map();
8547 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
8548 &BTRFS_I(inode)->runtime_flags);
8552 em->start = cur_offset;
8553 em->orig_start = cur_offset;
8554 em->len = ins.offset;
8555 em->block_start = ins.objectid;
8556 em->block_len = ins.offset;
8557 em->orig_block_len = ins.offset;
8558 em->ram_bytes = ins.offset;
8559 em->bdev = root->fs_info->fs_devices->latest_bdev;
8560 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
8561 em->generation = trans->transid;
8564 write_lock(&em_tree->lock);
8565 ret = add_extent_mapping(em_tree, em, 1);
8566 write_unlock(&em_tree->lock);
8569 btrfs_drop_extent_cache(inode, cur_offset,
8570 cur_offset + ins.offset - 1,
8573 free_extent_map(em);
8575 num_bytes -= ins.offset;
8576 cur_offset += ins.offset;
8577 *alloc_hint = ins.objectid + ins.offset;
8579 inode_inc_iversion(inode);
8580 inode->i_ctime = CURRENT_TIME;
8581 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
8582 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
8583 (actual_len > inode->i_size) &&
8584 (cur_offset > inode->i_size)) {
8585 if (cur_offset > actual_len)
8586 i_size = actual_len;
8588 i_size = cur_offset;
8589 i_size_write(inode, i_size);
8590 btrfs_ordered_update_i_size(inode, i_size, NULL);
8593 ret = btrfs_update_inode(trans, root, inode);
8596 btrfs_abort_transaction(trans, root, ret);
8598 btrfs_end_transaction(trans, root);
8603 btrfs_end_transaction(trans, root);
8608 int btrfs_prealloc_file_range(struct inode *inode, int mode,
8609 u64 start, u64 num_bytes, u64 min_size,
8610 loff_t actual_len, u64 *alloc_hint)
8612 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8613 min_size, actual_len, alloc_hint,
8617 int btrfs_prealloc_file_range_trans(struct inode *inode,
8618 struct btrfs_trans_handle *trans, int mode,
8619 u64 start, u64 num_bytes, u64 min_size,
8620 loff_t actual_len, u64 *alloc_hint)
8622 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8623 min_size, actual_len, alloc_hint, trans);
8626 static int btrfs_set_page_dirty(struct page *page)
8628 return __set_page_dirty_nobuffers(page);
8631 static int btrfs_permission(struct inode *inode, int mask)
8633 struct btrfs_root *root = BTRFS_I(inode)->root;
8634 umode_t mode = inode->i_mode;
8636 if (mask & MAY_WRITE &&
8637 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
8638 if (btrfs_root_readonly(root))
8640 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
8643 return generic_permission(inode, mask);
8646 static const struct inode_operations btrfs_dir_inode_operations = {
8647 .getattr = btrfs_getattr,
8648 .lookup = btrfs_lookup,
8649 .create = btrfs_create,
8650 .unlink = btrfs_unlink,
8652 .mkdir = btrfs_mkdir,
8653 .rmdir = btrfs_rmdir,
8654 .rename = btrfs_rename,
8655 .symlink = btrfs_symlink,
8656 .setattr = btrfs_setattr,
8657 .mknod = btrfs_mknod,
8658 .setxattr = btrfs_setxattr,
8659 .getxattr = btrfs_getxattr,
8660 .listxattr = btrfs_listxattr,
8661 .removexattr = btrfs_removexattr,
8662 .permission = btrfs_permission,
8663 .get_acl = btrfs_get_acl,
8664 .update_time = btrfs_update_time,
8666 static const struct inode_operations btrfs_dir_ro_inode_operations = {
8667 .lookup = btrfs_lookup,
8668 .permission = btrfs_permission,
8669 .get_acl = btrfs_get_acl,
8670 .update_time = btrfs_update_time,
8673 static const struct file_operations btrfs_dir_file_operations = {
8674 .llseek = generic_file_llseek,
8675 .read = generic_read_dir,
8676 .iterate = btrfs_real_readdir,
8677 .unlocked_ioctl = btrfs_ioctl,
8678 #ifdef CONFIG_COMPAT
8679 .compat_ioctl = btrfs_ioctl,
8681 .release = btrfs_release_file,
8682 .fsync = btrfs_sync_file,
8685 static struct extent_io_ops btrfs_extent_io_ops = {
8686 .fill_delalloc = run_delalloc_range,
8687 .submit_bio_hook = btrfs_submit_bio_hook,
8688 .merge_bio_hook = btrfs_merge_bio_hook,
8689 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
8690 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
8691 .writepage_start_hook = btrfs_writepage_start_hook,
8692 .set_bit_hook = btrfs_set_bit_hook,
8693 .clear_bit_hook = btrfs_clear_bit_hook,
8694 .merge_extent_hook = btrfs_merge_extent_hook,
8695 .split_extent_hook = btrfs_split_extent_hook,
8699 * btrfs doesn't support the bmap operation because swapfiles
8700 * use bmap to make a mapping of extents in the file. They assume
8701 * these extents won't change over the life of the file and they
8702 * use the bmap result to do IO directly to the drive.
8704 * the btrfs bmap call would return logical addresses that aren't
8705 * suitable for IO and they also will change frequently as COW
8706 * operations happen. So, swapfile + btrfs == corruption.
8708 * For now we're avoiding this by dropping bmap.
8710 static const struct address_space_operations btrfs_aops = {
8711 .readpage = btrfs_readpage,
8712 .writepage = btrfs_writepage,
8713 .writepages = btrfs_writepages,
8714 .readpages = btrfs_readpages,
8715 .direct_IO = btrfs_direct_IO,
8716 .invalidatepage = btrfs_invalidatepage,
8717 .releasepage = btrfs_releasepage,
8718 .set_page_dirty = btrfs_set_page_dirty,
8719 .error_remove_page = generic_error_remove_page,
8722 static const struct address_space_operations btrfs_symlink_aops = {
8723 .readpage = btrfs_readpage,
8724 .writepage = btrfs_writepage,
8725 .invalidatepage = btrfs_invalidatepage,
8726 .releasepage = btrfs_releasepage,
8729 static const struct inode_operations btrfs_file_inode_operations = {
8730 .getattr = btrfs_getattr,
8731 .setattr = btrfs_setattr,
8732 .setxattr = btrfs_setxattr,
8733 .getxattr = btrfs_getxattr,
8734 .listxattr = btrfs_listxattr,
8735 .removexattr = btrfs_removexattr,
8736 .permission = btrfs_permission,
8737 .fiemap = btrfs_fiemap,
8738 .get_acl = btrfs_get_acl,
8739 .update_time = btrfs_update_time,
8741 static const struct inode_operations btrfs_special_inode_operations = {
8742 .getattr = btrfs_getattr,
8743 .setattr = btrfs_setattr,
8744 .permission = btrfs_permission,
8745 .setxattr = btrfs_setxattr,
8746 .getxattr = btrfs_getxattr,
8747 .listxattr = btrfs_listxattr,
8748 .removexattr = btrfs_removexattr,
8749 .get_acl = btrfs_get_acl,
8750 .update_time = btrfs_update_time,
8752 static const struct inode_operations btrfs_symlink_inode_operations = {
8753 .readlink = generic_readlink,
8754 .follow_link = page_follow_link_light,
8755 .put_link = page_put_link,
8756 .getattr = btrfs_getattr,
8757 .setattr = btrfs_setattr,
8758 .permission = btrfs_permission,
8759 .setxattr = btrfs_setxattr,
8760 .getxattr = btrfs_getxattr,
8761 .listxattr = btrfs_listxattr,
8762 .removexattr = btrfs_removexattr,
8763 .get_acl = btrfs_get_acl,
8764 .update_time = btrfs_update_time,
8767 const struct dentry_operations btrfs_dentry_operations = {
8768 .d_delete = btrfs_dentry_delete,
8769 .d_release = btrfs_dentry_release,