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"
63 struct btrfs_iget_args {
64 struct btrfs_key *location;
65 struct btrfs_root *root;
68 static const struct inode_operations btrfs_dir_inode_operations;
69 static const struct inode_operations btrfs_symlink_inode_operations;
70 static const struct inode_operations btrfs_dir_ro_inode_operations;
71 static const struct inode_operations btrfs_special_inode_operations;
72 static const struct inode_operations btrfs_file_inode_operations;
73 static const struct address_space_operations btrfs_aops;
74 static const struct address_space_operations btrfs_symlink_aops;
75 static const struct file_operations btrfs_dir_file_operations;
76 static struct extent_io_ops btrfs_extent_io_ops;
78 static struct kmem_cache *btrfs_inode_cachep;
79 static struct kmem_cache *btrfs_delalloc_work_cachep;
80 struct kmem_cache *btrfs_trans_handle_cachep;
81 struct kmem_cache *btrfs_transaction_cachep;
82 struct kmem_cache *btrfs_path_cachep;
83 struct kmem_cache *btrfs_free_space_cachep;
86 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
87 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
88 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
89 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
90 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
91 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
92 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
93 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
96 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
97 static int btrfs_truncate(struct inode *inode);
98 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
99 static noinline int cow_file_range(struct inode *inode,
100 struct page *locked_page,
101 u64 start, u64 end, int *page_started,
102 unsigned long *nr_written, int unlock);
103 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
104 u64 len, u64 orig_start,
105 u64 block_start, u64 block_len,
106 u64 orig_block_len, u64 ram_bytes,
109 static int btrfs_dirty_inode(struct inode *inode);
111 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
112 struct inode *inode, struct inode *dir,
113 const struct qstr *qstr)
117 err = btrfs_init_acl(trans, inode, dir);
119 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
124 * this does all the hard work for inserting an inline extent into
125 * the btree. The caller should have done a btrfs_drop_extents so that
126 * no overlapping inline items exist in the btree
128 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
129 struct btrfs_path *path, int extent_inserted,
130 struct btrfs_root *root, struct inode *inode,
131 u64 start, size_t size, size_t compressed_size,
133 struct page **compressed_pages)
135 struct extent_buffer *leaf;
136 struct page *page = NULL;
139 struct btrfs_file_extent_item *ei;
142 size_t cur_size = size;
143 unsigned long offset;
145 if (compressed_size && compressed_pages)
146 cur_size = compressed_size;
148 inode_add_bytes(inode, size);
150 if (!extent_inserted) {
151 struct btrfs_key key;
154 key.objectid = btrfs_ino(inode);
156 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
158 datasize = btrfs_file_extent_calc_inline_size(cur_size);
159 path->leave_spinning = 1;
160 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_release_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);
227 * conditionally insert an inline extent into the file. This
228 * does the checks required to make sure the data is small enough
229 * to fit as an inline extent.
231 static noinline int cow_file_range_inline(struct btrfs_root *root,
232 struct inode *inode, u64 start,
233 u64 end, size_t compressed_size,
235 struct page **compressed_pages)
237 struct btrfs_trans_handle *trans;
238 u64 isize = i_size_read(inode);
239 u64 actual_end = min(end + 1, isize);
240 u64 inline_len = actual_end - start;
241 u64 aligned_end = ALIGN(end, root->sectorsize);
242 u64 data_len = inline_len;
244 struct btrfs_path *path;
245 int extent_inserted = 0;
246 u32 extent_item_size;
249 data_len = compressed_size;
252 actual_end >= PAGE_CACHE_SIZE ||
253 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
255 (actual_end & (root->sectorsize - 1)) == 0) ||
257 data_len > root->fs_info->max_inline) {
261 path = btrfs_alloc_path();
265 trans = btrfs_join_transaction(root);
267 btrfs_free_path(path);
268 return PTR_ERR(trans);
270 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
272 if (compressed_size && compressed_pages)
273 extent_item_size = btrfs_file_extent_calc_inline_size(
276 extent_item_size = btrfs_file_extent_calc_inline_size(
279 ret = __btrfs_drop_extents(trans, root, inode, path,
280 start, aligned_end, NULL,
281 1, 1, extent_item_size, &extent_inserted);
283 btrfs_abort_transaction(trans, root, ret);
287 if (isize > actual_end)
288 inline_len = min_t(u64, isize, actual_end);
289 ret = insert_inline_extent(trans, path, extent_inserted,
291 inline_len, compressed_size,
292 compress_type, compressed_pages);
293 if (ret && ret != -ENOSPC) {
294 btrfs_abort_transaction(trans, root, ret);
296 } else if (ret == -ENOSPC) {
301 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
302 btrfs_delalloc_release_metadata(inode, end + 1 - start);
303 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
305 btrfs_free_path(path);
306 btrfs_end_transaction(trans, root);
310 struct async_extent {
315 unsigned long nr_pages;
317 struct list_head list;
322 struct btrfs_root *root;
323 struct page *locked_page;
326 struct list_head extents;
327 struct btrfs_work_struct work;
330 static noinline int add_async_extent(struct async_cow *cow,
331 u64 start, u64 ram_size,
334 unsigned long nr_pages,
337 struct async_extent *async_extent;
339 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
340 BUG_ON(!async_extent); /* -ENOMEM */
341 async_extent->start = start;
342 async_extent->ram_size = ram_size;
343 async_extent->compressed_size = compressed_size;
344 async_extent->pages = pages;
345 async_extent->nr_pages = nr_pages;
346 async_extent->compress_type = compress_type;
347 list_add_tail(&async_extent->list, &cow->extents);
352 * we create compressed extents in two phases. The first
353 * phase compresses a range of pages that have already been
354 * locked (both pages and state bits are locked).
356 * This is done inside an ordered work queue, and the compression
357 * is spread across many cpus. The actual IO submission is step
358 * two, and the ordered work queue takes care of making sure that
359 * happens in the same order things were put onto the queue by
360 * writepages and friends.
362 * If this code finds it can't get good compression, it puts an
363 * entry onto the work queue to write the uncompressed bytes. This
364 * makes sure that both compressed inodes and uncompressed inodes
365 * are written in the same order that the flusher thread sent them
368 static noinline int compress_file_range(struct inode *inode,
369 struct page *locked_page,
371 struct async_cow *async_cow,
374 struct btrfs_root *root = BTRFS_I(inode)->root;
376 u64 blocksize = root->sectorsize;
378 u64 isize = i_size_read(inode);
380 struct page **pages = NULL;
381 unsigned long nr_pages;
382 unsigned long nr_pages_ret = 0;
383 unsigned long total_compressed = 0;
384 unsigned long total_in = 0;
385 unsigned long max_compressed = 128 * 1024;
386 unsigned long max_uncompressed = 128 * 1024;
389 int compress_type = root->fs_info->compress_type;
392 /* if this is a small write inside eof, kick off a defrag */
393 if ((end - start + 1) < 16 * 1024 &&
394 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
395 btrfs_add_inode_defrag(NULL, inode);
397 actual_end = min_t(u64, isize, end + 1);
400 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
401 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
404 * we don't want to send crud past the end of i_size through
405 * compression, that's just a waste of CPU time. So, if the
406 * end of the file is before the start of our current
407 * requested range of bytes, we bail out to the uncompressed
408 * cleanup code that can deal with all of this.
410 * It isn't really the fastest way to fix things, but this is a
411 * very uncommon corner.
413 if (actual_end <= start)
414 goto cleanup_and_bail_uncompressed;
416 total_compressed = actual_end - start;
418 /* we want to make sure that amount of ram required to uncompress
419 * an extent is reasonable, so we limit the total size in ram
420 * of a compressed extent to 128k. This is a crucial number
421 * because it also controls how easily we can spread reads across
422 * cpus for decompression.
424 * We also want to make sure the amount of IO required to do
425 * a random read is reasonably small, so we limit the size of
426 * a compressed extent to 128k.
428 total_compressed = min(total_compressed, max_uncompressed);
429 num_bytes = ALIGN(end - start + 1, blocksize);
430 num_bytes = max(blocksize, num_bytes);
435 * we do compression for mount -o compress and when the
436 * inode has not been flagged as nocompress. This flag can
437 * change at any time if we discover bad compression ratios.
439 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
440 (btrfs_test_opt(root, COMPRESS) ||
441 (BTRFS_I(inode)->force_compress) ||
442 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
444 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
446 /* just bail out to the uncompressed code */
450 if (BTRFS_I(inode)->force_compress)
451 compress_type = BTRFS_I(inode)->force_compress;
454 * we need to call clear_page_dirty_for_io on each
455 * page in the range. Otherwise applications with the file
456 * mmap'd can wander in and change the page contents while
457 * we are compressing them.
459 * If the compression fails for any reason, we set the pages
460 * dirty again later on.
462 extent_range_clear_dirty_for_io(inode, start, end);
464 ret = btrfs_compress_pages(compress_type,
465 inode->i_mapping, start,
466 total_compressed, pages,
467 nr_pages, &nr_pages_ret,
473 unsigned long offset = total_compressed &
474 (PAGE_CACHE_SIZE - 1);
475 struct page *page = pages[nr_pages_ret - 1];
478 /* zero the tail end of the last page, we might be
479 * sending it down to disk
482 kaddr = kmap_atomic(page);
483 memset(kaddr + offset, 0,
484 PAGE_CACHE_SIZE - offset);
485 kunmap_atomic(kaddr);
492 /* lets try to make an inline extent */
493 if (ret || total_in < (actual_end - start)) {
494 /* we didn't compress the entire range, try
495 * to make an uncompressed inline extent.
497 ret = cow_file_range_inline(root, inode, start, end,
500 /* try making a compressed inline extent */
501 ret = cow_file_range_inline(root, inode, start, end,
503 compress_type, pages);
506 unsigned long clear_flags = EXTENT_DELALLOC |
508 clear_flags |= (ret < 0) ? EXTENT_DO_ACCOUNTING : 0;
511 * inline extent creation worked or returned error,
512 * we don't need to create any more async work items.
513 * Unlock and free up our temp pages.
515 extent_clear_unlock_delalloc(inode, start, end, NULL,
516 clear_flags, PAGE_UNLOCK |
526 * we aren't doing an inline extent round the compressed size
527 * up to a block size boundary so the allocator does sane
530 total_compressed = ALIGN(total_compressed, blocksize);
533 * one last check to make sure the compression is really a
534 * win, compare the page count read with the blocks on disk
536 total_in = ALIGN(total_in, PAGE_CACHE_SIZE);
537 if (total_compressed >= total_in) {
540 num_bytes = total_in;
543 if (!will_compress && pages) {
545 * the compression code ran but failed to make things smaller,
546 * free any pages it allocated and our page pointer array
548 for (i = 0; i < nr_pages_ret; i++) {
549 WARN_ON(pages[i]->mapping);
550 page_cache_release(pages[i]);
554 total_compressed = 0;
557 /* flag the file so we don't compress in the future */
558 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
559 !(BTRFS_I(inode)->force_compress)) {
560 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
566 /* the async work queues will take care of doing actual
567 * allocation on disk for these compressed pages,
568 * and will submit them to the elevator.
570 add_async_extent(async_cow, start, num_bytes,
571 total_compressed, pages, nr_pages_ret,
574 if (start + num_bytes < end) {
581 cleanup_and_bail_uncompressed:
583 * No compression, but we still need to write the pages in
584 * the file we've been given so far. redirty the locked
585 * page if it corresponds to our extent and set things up
586 * for the async work queue to run cow_file_range to do
587 * the normal delalloc dance
589 if (page_offset(locked_page) >= start &&
590 page_offset(locked_page) <= end) {
591 __set_page_dirty_nobuffers(locked_page);
592 /* unlocked later on in the async handlers */
595 extent_range_redirty_for_io(inode, start, end);
596 add_async_extent(async_cow, start, end - start + 1,
597 0, NULL, 0, BTRFS_COMPRESS_NONE);
605 for (i = 0; i < nr_pages_ret; i++) {
606 WARN_ON(pages[i]->mapping);
607 page_cache_release(pages[i]);
615 * phase two of compressed writeback. This is the ordered portion
616 * of the code, which only gets called in the order the work was
617 * queued. We walk all the async extents created by compress_file_range
618 * and send them down to the disk.
620 static noinline int submit_compressed_extents(struct inode *inode,
621 struct async_cow *async_cow)
623 struct async_extent *async_extent;
625 struct btrfs_key ins;
626 struct extent_map *em;
627 struct btrfs_root *root = BTRFS_I(inode)->root;
628 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
629 struct extent_io_tree *io_tree;
632 if (list_empty(&async_cow->extents))
636 while (!list_empty(&async_cow->extents)) {
637 async_extent = list_entry(async_cow->extents.next,
638 struct async_extent, list);
639 list_del(&async_extent->list);
641 io_tree = &BTRFS_I(inode)->io_tree;
644 /* did the compression code fall back to uncompressed IO? */
645 if (!async_extent->pages) {
646 int page_started = 0;
647 unsigned long nr_written = 0;
649 lock_extent(io_tree, async_extent->start,
650 async_extent->start +
651 async_extent->ram_size - 1);
653 /* allocate blocks */
654 ret = cow_file_range(inode, async_cow->locked_page,
656 async_extent->start +
657 async_extent->ram_size - 1,
658 &page_started, &nr_written, 0);
663 * if page_started, cow_file_range inserted an
664 * inline extent and took care of all the unlocking
665 * and IO for us. Otherwise, we need to submit
666 * all those pages down to the drive.
668 if (!page_started && !ret)
669 extent_write_locked_range(io_tree,
670 inode, async_extent->start,
671 async_extent->start +
672 async_extent->ram_size - 1,
676 unlock_page(async_cow->locked_page);
682 lock_extent(io_tree, async_extent->start,
683 async_extent->start + async_extent->ram_size - 1);
685 ret = btrfs_reserve_extent(root,
686 async_extent->compressed_size,
687 async_extent->compressed_size,
688 0, alloc_hint, &ins, 1);
692 for (i = 0; i < async_extent->nr_pages; i++) {
693 WARN_ON(async_extent->pages[i]->mapping);
694 page_cache_release(async_extent->pages[i]);
696 kfree(async_extent->pages);
697 async_extent->nr_pages = 0;
698 async_extent->pages = NULL;
700 if (ret == -ENOSPC) {
701 unlock_extent(io_tree, async_extent->start,
702 async_extent->start +
703 async_extent->ram_size - 1);
710 * here we're doing allocation and writeback of the
713 btrfs_drop_extent_cache(inode, async_extent->start,
714 async_extent->start +
715 async_extent->ram_size - 1, 0);
717 em = alloc_extent_map();
720 goto out_free_reserve;
722 em->start = async_extent->start;
723 em->len = async_extent->ram_size;
724 em->orig_start = em->start;
725 em->mod_start = em->start;
726 em->mod_len = em->len;
728 em->block_start = ins.objectid;
729 em->block_len = ins.offset;
730 em->orig_block_len = ins.offset;
731 em->ram_bytes = async_extent->ram_size;
732 em->bdev = root->fs_info->fs_devices->latest_bdev;
733 em->compress_type = async_extent->compress_type;
734 set_bit(EXTENT_FLAG_PINNED, &em->flags);
735 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
739 write_lock(&em_tree->lock);
740 ret = add_extent_mapping(em_tree, em, 1);
741 write_unlock(&em_tree->lock);
742 if (ret != -EEXIST) {
746 btrfs_drop_extent_cache(inode, async_extent->start,
747 async_extent->start +
748 async_extent->ram_size - 1, 0);
752 goto out_free_reserve;
754 ret = btrfs_add_ordered_extent_compress(inode,
757 async_extent->ram_size,
759 BTRFS_ORDERED_COMPRESSED,
760 async_extent->compress_type);
762 goto out_free_reserve;
765 * clear dirty, set writeback and unlock the pages.
767 extent_clear_unlock_delalloc(inode, async_extent->start,
768 async_extent->start +
769 async_extent->ram_size - 1,
770 NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
771 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
773 ret = btrfs_submit_compressed_write(inode,
775 async_extent->ram_size,
777 ins.offset, async_extent->pages,
778 async_extent->nr_pages);
779 alloc_hint = ins.objectid + ins.offset;
789 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
791 extent_clear_unlock_delalloc(inode, async_extent->start,
792 async_extent->start +
793 async_extent->ram_size - 1,
794 NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
795 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING,
796 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
797 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK);
802 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
805 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
806 struct extent_map *em;
809 read_lock(&em_tree->lock);
810 em = search_extent_mapping(em_tree, start, num_bytes);
813 * if block start isn't an actual block number then find the
814 * first block in this inode and use that as a hint. If that
815 * block is also bogus then just don't worry about it.
817 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
819 em = search_extent_mapping(em_tree, 0, 0);
820 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
821 alloc_hint = em->block_start;
825 alloc_hint = em->block_start;
829 read_unlock(&em_tree->lock);
835 * when extent_io.c finds a delayed allocation range in the file,
836 * the call backs end up in this code. The basic idea is to
837 * allocate extents on disk for the range, and create ordered data structs
838 * in ram to track those extents.
840 * locked_page is the page that writepage had locked already. We use
841 * it to make sure we don't do extra locks or unlocks.
843 * *page_started is set to one if we unlock locked_page and do everything
844 * required to start IO on it. It may be clean and already done with
847 static noinline int cow_file_range(struct inode *inode,
848 struct page *locked_page,
849 u64 start, u64 end, int *page_started,
850 unsigned long *nr_written,
853 struct btrfs_root *root = BTRFS_I(inode)->root;
856 unsigned long ram_size;
859 u64 blocksize = root->sectorsize;
860 struct btrfs_key ins;
861 struct extent_map *em;
862 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
865 if (btrfs_is_free_space_inode(inode)) {
871 num_bytes = ALIGN(end - start + 1, blocksize);
872 num_bytes = max(blocksize, num_bytes);
873 disk_num_bytes = num_bytes;
875 /* if this is a small write inside eof, kick off defrag */
876 if (num_bytes < 64 * 1024 &&
877 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
878 btrfs_add_inode_defrag(NULL, inode);
881 /* lets try to make an inline extent */
882 ret = cow_file_range_inline(root, inode, start, end, 0, 0,
885 extent_clear_unlock_delalloc(inode, start, end, NULL,
886 EXTENT_LOCKED | EXTENT_DELALLOC |
887 EXTENT_DEFRAG, PAGE_UNLOCK |
888 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
891 *nr_written = *nr_written +
892 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
895 } else if (ret < 0) {
900 BUG_ON(disk_num_bytes >
901 btrfs_super_total_bytes(root->fs_info->super_copy));
903 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
904 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
906 while (disk_num_bytes > 0) {
909 cur_alloc_size = disk_num_bytes;
910 ret = btrfs_reserve_extent(root, cur_alloc_size,
911 root->sectorsize, 0, alloc_hint,
916 em = alloc_extent_map();
922 em->orig_start = em->start;
923 ram_size = ins.offset;
924 em->len = ins.offset;
925 em->mod_start = em->start;
926 em->mod_len = em->len;
928 em->block_start = ins.objectid;
929 em->block_len = ins.offset;
930 em->orig_block_len = ins.offset;
931 em->ram_bytes = ram_size;
932 em->bdev = root->fs_info->fs_devices->latest_bdev;
933 set_bit(EXTENT_FLAG_PINNED, &em->flags);
937 write_lock(&em_tree->lock);
938 ret = add_extent_mapping(em_tree, em, 1);
939 write_unlock(&em_tree->lock);
940 if (ret != -EEXIST) {
944 btrfs_drop_extent_cache(inode, start,
945 start + ram_size - 1, 0);
950 cur_alloc_size = ins.offset;
951 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
952 ram_size, cur_alloc_size, 0);
956 if (root->root_key.objectid ==
957 BTRFS_DATA_RELOC_TREE_OBJECTID) {
958 ret = btrfs_reloc_clone_csums(inode, start,
964 if (disk_num_bytes < cur_alloc_size)
967 /* we're not doing compressed IO, don't unlock the first
968 * page (which the caller expects to stay locked), don't
969 * clear any dirty bits and don't set any writeback bits
971 * Do set the Private2 bit so we know this page was properly
972 * setup for writepage
974 op = unlock ? PAGE_UNLOCK : 0;
975 op |= PAGE_SET_PRIVATE2;
977 extent_clear_unlock_delalloc(inode, start,
978 start + ram_size - 1, locked_page,
979 EXTENT_LOCKED | EXTENT_DELALLOC,
981 disk_num_bytes -= cur_alloc_size;
982 num_bytes -= cur_alloc_size;
983 alloc_hint = ins.objectid + ins.offset;
984 start += cur_alloc_size;
990 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
992 extent_clear_unlock_delalloc(inode, start, end, locked_page,
993 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
994 EXTENT_DELALLOC | EXTENT_DEFRAG,
995 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
996 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK);
1001 * work queue call back to started compression on a file and pages
1003 static noinline void async_cow_start(struct btrfs_work_struct *work)
1005 struct async_cow *async_cow;
1007 async_cow = container_of(work, struct async_cow, work);
1009 compress_file_range(async_cow->inode, async_cow->locked_page,
1010 async_cow->start, async_cow->end, async_cow,
1012 if (num_added == 0) {
1013 btrfs_add_delayed_iput(async_cow->inode);
1014 async_cow->inode = NULL;
1019 * work queue call back to submit previously compressed pages
1021 static noinline void async_cow_submit(struct btrfs_work_struct *work)
1023 struct async_cow *async_cow;
1024 struct btrfs_root *root;
1025 unsigned long nr_pages;
1027 async_cow = container_of(work, struct async_cow, work);
1029 root = async_cow->root;
1030 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
1033 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
1035 waitqueue_active(&root->fs_info->async_submit_wait))
1036 wake_up(&root->fs_info->async_submit_wait);
1038 if (async_cow->inode)
1039 submit_compressed_extents(async_cow->inode, async_cow);
1042 static noinline void async_cow_free(struct btrfs_work_struct *work)
1044 struct async_cow *async_cow;
1045 async_cow = container_of(work, struct async_cow, work);
1046 if (async_cow->inode)
1047 btrfs_add_delayed_iput(async_cow->inode);
1051 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1052 u64 start, u64 end, int *page_started,
1053 unsigned long *nr_written)
1055 struct async_cow *async_cow;
1056 struct btrfs_root *root = BTRFS_I(inode)->root;
1057 unsigned long nr_pages;
1059 int limit = 10 * 1024 * 1024;
1061 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1062 1, 0, NULL, GFP_NOFS);
1063 while (start < end) {
1064 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1065 BUG_ON(!async_cow); /* -ENOMEM */
1066 async_cow->inode = igrab(inode);
1067 async_cow->root = root;
1068 async_cow->locked_page = locked_page;
1069 async_cow->start = start;
1071 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
1074 cur_end = min(end, start + 512 * 1024 - 1);
1076 async_cow->end = cur_end;
1077 INIT_LIST_HEAD(&async_cow->extents);
1079 btrfs_init_work(&async_cow->work, async_cow_start,
1080 async_cow_submit, async_cow_free);
1082 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1084 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1086 btrfs_queue_work(root->fs_info->delalloc_workers,
1089 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1090 wait_event(root->fs_info->async_submit_wait,
1091 (atomic_read(&root->fs_info->async_delalloc_pages) <
1095 while (atomic_read(&root->fs_info->async_submit_draining) &&
1096 atomic_read(&root->fs_info->async_delalloc_pages)) {
1097 wait_event(root->fs_info->async_submit_wait,
1098 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1102 *nr_written += nr_pages;
1103 start = cur_end + 1;
1109 static noinline int csum_exist_in_range(struct btrfs_root *root,
1110 u64 bytenr, u64 num_bytes)
1113 struct btrfs_ordered_sum *sums;
1116 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1117 bytenr + num_bytes - 1, &list, 0);
1118 if (ret == 0 && list_empty(&list))
1121 while (!list_empty(&list)) {
1122 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1123 list_del(&sums->list);
1130 * when nowcow writeback call back. This checks for snapshots or COW copies
1131 * of the extents that exist in the file, and COWs the file as required.
1133 * If no cow copies or snapshots exist, we write directly to the existing
1136 static noinline int run_delalloc_nocow(struct inode *inode,
1137 struct page *locked_page,
1138 u64 start, u64 end, int *page_started, int force,
1139 unsigned long *nr_written)
1141 struct btrfs_root *root = BTRFS_I(inode)->root;
1142 struct btrfs_trans_handle *trans;
1143 struct extent_buffer *leaf;
1144 struct btrfs_path *path;
1145 struct btrfs_file_extent_item *fi;
1146 struct btrfs_key found_key;
1161 u64 ino = btrfs_ino(inode);
1163 path = btrfs_alloc_path();
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);
1175 nolock = btrfs_is_free_space_inode(inode);
1178 trans = btrfs_join_transaction_nolock(root);
1180 trans = btrfs_join_transaction(root);
1182 if (IS_ERR(trans)) {
1183 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1184 EXTENT_LOCKED | EXTENT_DELALLOC |
1185 EXTENT_DO_ACCOUNTING |
1186 EXTENT_DEFRAG, PAGE_UNLOCK |
1188 PAGE_SET_WRITEBACK |
1189 PAGE_END_WRITEBACK);
1190 btrfs_free_path(path);
1191 return PTR_ERR(trans);
1194 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1196 cow_start = (u64)-1;
1199 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1203 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1204 leaf = path->nodes[0];
1205 btrfs_item_key_to_cpu(leaf, &found_key,
1206 path->slots[0] - 1);
1207 if (found_key.objectid == ino &&
1208 found_key.type == BTRFS_EXTENT_DATA_KEY)
1213 leaf = path->nodes[0];
1214 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1215 ret = btrfs_next_leaf(root, path);
1220 leaf = path->nodes[0];
1226 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1228 if (found_key.objectid > ino ||
1229 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1230 found_key.offset > end)
1233 if (found_key.offset > cur_offset) {
1234 extent_end = found_key.offset;
1239 fi = btrfs_item_ptr(leaf, path->slots[0],
1240 struct btrfs_file_extent_item);
1241 extent_type = btrfs_file_extent_type(leaf, fi);
1243 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1244 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1245 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1246 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1247 extent_offset = btrfs_file_extent_offset(leaf, fi);
1248 extent_end = found_key.offset +
1249 btrfs_file_extent_num_bytes(leaf, fi);
1251 btrfs_file_extent_disk_num_bytes(leaf, fi);
1252 if (extent_end <= start) {
1256 if (disk_bytenr == 0)
1258 if (btrfs_file_extent_compression(leaf, fi) ||
1259 btrfs_file_extent_encryption(leaf, fi) ||
1260 btrfs_file_extent_other_encoding(leaf, fi))
1262 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1264 if (btrfs_extent_readonly(root, disk_bytenr))
1266 if (btrfs_cross_ref_exist(trans, root, ino,
1268 extent_offset, disk_bytenr))
1270 disk_bytenr += extent_offset;
1271 disk_bytenr += cur_offset - found_key.offset;
1272 num_bytes = min(end + 1, extent_end) - cur_offset;
1274 * force cow if csum exists in the range.
1275 * this ensure that csum for a given extent are
1276 * either valid or do not exist.
1278 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1281 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1282 extent_end = found_key.offset +
1283 btrfs_file_extent_inline_len(leaf,
1284 path->slots[0], fi);
1285 extent_end = ALIGN(extent_end, root->sectorsize);
1290 if (extent_end <= start) {
1295 if (cow_start == (u64)-1)
1296 cow_start = cur_offset;
1297 cur_offset = extent_end;
1298 if (cur_offset > end)
1304 btrfs_release_path(path);
1305 if (cow_start != (u64)-1) {
1306 ret = cow_file_range(inode, locked_page,
1307 cow_start, found_key.offset - 1,
1308 page_started, nr_written, 1);
1311 cow_start = (u64)-1;
1314 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1315 struct extent_map *em;
1316 struct extent_map_tree *em_tree;
1317 em_tree = &BTRFS_I(inode)->extent_tree;
1318 em = alloc_extent_map();
1319 BUG_ON(!em); /* -ENOMEM */
1320 em->start = cur_offset;
1321 em->orig_start = found_key.offset - extent_offset;
1322 em->len = num_bytes;
1323 em->block_len = num_bytes;
1324 em->block_start = disk_bytenr;
1325 em->orig_block_len = disk_num_bytes;
1326 em->ram_bytes = ram_bytes;
1327 em->bdev = root->fs_info->fs_devices->latest_bdev;
1328 em->mod_start = em->start;
1329 em->mod_len = em->len;
1330 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1331 set_bit(EXTENT_FLAG_FILLING, &em->flags);
1332 em->generation = -1;
1334 write_lock(&em_tree->lock);
1335 ret = add_extent_mapping(em_tree, em, 1);
1336 write_unlock(&em_tree->lock);
1337 if (ret != -EEXIST) {
1338 free_extent_map(em);
1341 btrfs_drop_extent_cache(inode, em->start,
1342 em->start + em->len - 1, 0);
1344 type = BTRFS_ORDERED_PREALLOC;
1346 type = BTRFS_ORDERED_NOCOW;
1349 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1350 num_bytes, num_bytes, type);
1351 BUG_ON(ret); /* -ENOMEM */
1353 if (root->root_key.objectid ==
1354 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1355 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1361 extent_clear_unlock_delalloc(inode, cur_offset,
1362 cur_offset + num_bytes - 1,
1363 locked_page, EXTENT_LOCKED |
1364 EXTENT_DELALLOC, PAGE_UNLOCK |
1366 cur_offset = extent_end;
1367 if (cur_offset > end)
1370 btrfs_release_path(path);
1372 if (cur_offset <= end && cow_start == (u64)-1) {
1373 cow_start = cur_offset;
1377 if (cow_start != (u64)-1) {
1378 ret = cow_file_range(inode, locked_page, cow_start, end,
1379 page_started, nr_written, 1);
1385 err = btrfs_end_transaction(trans, root);
1389 if (ret && cur_offset < end)
1390 extent_clear_unlock_delalloc(inode, cur_offset, end,
1391 locked_page, EXTENT_LOCKED |
1392 EXTENT_DELALLOC | EXTENT_DEFRAG |
1393 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1395 PAGE_SET_WRITEBACK |
1396 PAGE_END_WRITEBACK);
1397 btrfs_free_path(path);
1402 * extent_io.c call back to do delayed allocation processing
1404 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1405 u64 start, u64 end, int *page_started,
1406 unsigned long *nr_written)
1409 struct btrfs_root *root = BTRFS_I(inode)->root;
1411 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
1412 ret = run_delalloc_nocow(inode, locked_page, start, end,
1413 page_started, 1, nr_written);
1414 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
1415 ret = run_delalloc_nocow(inode, locked_page, start, end,
1416 page_started, 0, nr_written);
1417 } else if (!btrfs_test_opt(root, COMPRESS) &&
1418 !(BTRFS_I(inode)->force_compress) &&
1419 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
1420 ret = cow_file_range(inode, locked_page, start, end,
1421 page_started, nr_written, 1);
1423 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1424 &BTRFS_I(inode)->runtime_flags);
1425 ret = cow_file_range_async(inode, locked_page, start, end,
1426 page_started, nr_written);
1431 static void btrfs_split_extent_hook(struct inode *inode,
1432 struct extent_state *orig, u64 split)
1434 /* not delalloc, ignore it */
1435 if (!(orig->state & EXTENT_DELALLOC))
1438 spin_lock(&BTRFS_I(inode)->lock);
1439 BTRFS_I(inode)->outstanding_extents++;
1440 spin_unlock(&BTRFS_I(inode)->lock);
1444 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1445 * extents so we can keep track of new extents that are just merged onto old
1446 * extents, such as when we are doing sequential writes, so we can properly
1447 * account for the metadata space we'll need.
1449 static void btrfs_merge_extent_hook(struct inode *inode,
1450 struct extent_state *new,
1451 struct extent_state *other)
1453 /* not delalloc, ignore it */
1454 if (!(other->state & EXTENT_DELALLOC))
1457 spin_lock(&BTRFS_I(inode)->lock);
1458 BTRFS_I(inode)->outstanding_extents--;
1459 spin_unlock(&BTRFS_I(inode)->lock);
1462 static void btrfs_add_delalloc_inodes(struct btrfs_root *root,
1463 struct inode *inode)
1465 spin_lock(&root->delalloc_lock);
1466 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1467 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1468 &root->delalloc_inodes);
1469 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1470 &BTRFS_I(inode)->runtime_flags);
1471 root->nr_delalloc_inodes++;
1472 if (root->nr_delalloc_inodes == 1) {
1473 spin_lock(&root->fs_info->delalloc_root_lock);
1474 BUG_ON(!list_empty(&root->delalloc_root));
1475 list_add_tail(&root->delalloc_root,
1476 &root->fs_info->delalloc_roots);
1477 spin_unlock(&root->fs_info->delalloc_root_lock);
1480 spin_unlock(&root->delalloc_lock);
1483 static void btrfs_del_delalloc_inode(struct btrfs_root *root,
1484 struct inode *inode)
1486 spin_lock(&root->delalloc_lock);
1487 if (!list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1488 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1489 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1490 &BTRFS_I(inode)->runtime_flags);
1491 root->nr_delalloc_inodes--;
1492 if (!root->nr_delalloc_inodes) {
1493 spin_lock(&root->fs_info->delalloc_root_lock);
1494 BUG_ON(list_empty(&root->delalloc_root));
1495 list_del_init(&root->delalloc_root);
1496 spin_unlock(&root->fs_info->delalloc_root_lock);
1499 spin_unlock(&root->delalloc_lock);
1503 * extent_io.c set_bit_hook, used to track delayed allocation
1504 * bytes in this file, and to maintain the list of inodes that
1505 * have pending delalloc work to be done.
1507 static void btrfs_set_bit_hook(struct inode *inode,
1508 struct extent_state *state, unsigned long *bits)
1512 * set_bit and clear bit hooks normally require _irqsave/restore
1513 * but in this case, we are only testing for the DELALLOC
1514 * bit, which is only set or cleared with irqs on
1516 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1517 struct btrfs_root *root = BTRFS_I(inode)->root;
1518 u64 len = state->end + 1 - state->start;
1519 bool do_list = !btrfs_is_free_space_inode(inode);
1521 if (*bits & EXTENT_FIRST_DELALLOC) {
1522 *bits &= ~EXTENT_FIRST_DELALLOC;
1524 spin_lock(&BTRFS_I(inode)->lock);
1525 BTRFS_I(inode)->outstanding_extents++;
1526 spin_unlock(&BTRFS_I(inode)->lock);
1529 __percpu_counter_add(&root->fs_info->delalloc_bytes, len,
1530 root->fs_info->delalloc_batch);
1531 spin_lock(&BTRFS_I(inode)->lock);
1532 BTRFS_I(inode)->delalloc_bytes += len;
1533 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1534 &BTRFS_I(inode)->runtime_flags))
1535 btrfs_add_delalloc_inodes(root, inode);
1536 spin_unlock(&BTRFS_I(inode)->lock);
1541 * extent_io.c clear_bit_hook, see set_bit_hook for why
1543 static void btrfs_clear_bit_hook(struct inode *inode,
1544 struct extent_state *state,
1545 unsigned long *bits)
1548 * set_bit and clear bit hooks normally require _irqsave/restore
1549 * but in this case, we are only testing for the DELALLOC
1550 * bit, which is only set or cleared with irqs on
1552 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1553 struct btrfs_root *root = BTRFS_I(inode)->root;
1554 u64 len = state->end + 1 - state->start;
1555 bool do_list = !btrfs_is_free_space_inode(inode);
1557 if (*bits & EXTENT_FIRST_DELALLOC) {
1558 *bits &= ~EXTENT_FIRST_DELALLOC;
1559 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1560 spin_lock(&BTRFS_I(inode)->lock);
1561 BTRFS_I(inode)->outstanding_extents--;
1562 spin_unlock(&BTRFS_I(inode)->lock);
1566 * We don't reserve metadata space for space cache inodes so we
1567 * don't need to call dellalloc_release_metadata if there is an
1570 if (*bits & EXTENT_DO_ACCOUNTING &&
1571 root != root->fs_info->tree_root)
1572 btrfs_delalloc_release_metadata(inode, len);
1574 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1575 && do_list && !(state->state & EXTENT_NORESERVE))
1576 btrfs_free_reserved_data_space(inode, len);
1578 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len,
1579 root->fs_info->delalloc_batch);
1580 spin_lock(&BTRFS_I(inode)->lock);
1581 BTRFS_I(inode)->delalloc_bytes -= len;
1582 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1583 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1584 &BTRFS_I(inode)->runtime_flags))
1585 btrfs_del_delalloc_inode(root, inode);
1586 spin_unlock(&BTRFS_I(inode)->lock);
1591 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1592 * we don't create bios that span stripes or chunks
1594 int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
1595 size_t size, struct bio *bio,
1596 unsigned long bio_flags)
1598 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1599 u64 logical = (u64)bio->bi_sector << 9;
1604 if (bio_flags & EXTENT_BIO_COMPRESSED)
1607 length = bio->bi_size;
1608 map_length = length;
1609 ret = btrfs_map_block(root->fs_info, rw, logical,
1610 &map_length, NULL, 0);
1611 /* Will always return 0 with map_multi == NULL */
1613 if (map_length < length + size)
1619 * in order to insert checksums into the metadata in large chunks,
1620 * we wait until bio submission time. All the pages in the bio are
1621 * checksummed and sums are attached onto the ordered extent record.
1623 * At IO completion time the cums attached on the ordered extent record
1624 * are inserted into the btree
1626 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1627 struct bio *bio, int mirror_num,
1628 unsigned long bio_flags,
1631 struct btrfs_root *root = BTRFS_I(inode)->root;
1634 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1635 BUG_ON(ret); /* -ENOMEM */
1640 * in order to insert checksums into the metadata in large chunks,
1641 * we wait until bio submission time. All the pages in the bio are
1642 * checksummed and sums are attached onto the ordered extent record.
1644 * At IO completion time the cums attached on the ordered extent record
1645 * are inserted into the btree
1647 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1648 int mirror_num, unsigned long bio_flags,
1651 struct btrfs_root *root = BTRFS_I(inode)->root;
1654 ret = btrfs_map_bio(root, rw, bio, mirror_num, 1);
1656 bio_endio(bio, ret);
1661 * extent_io.c submission hook. This does the right thing for csum calculation
1662 * on write, or reading the csums from the tree before a read
1664 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1665 int mirror_num, unsigned long bio_flags,
1668 struct btrfs_root *root = BTRFS_I(inode)->root;
1672 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
1674 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1676 if (btrfs_is_free_space_inode(inode))
1679 if (!(rw & REQ_WRITE)) {
1680 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata);
1684 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1685 ret = btrfs_submit_compressed_read(inode, bio,
1689 } else if (!skip_sum) {
1690 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1695 } else if (async && !skip_sum) {
1696 /* csum items have already been cloned */
1697 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1699 /* we're doing a write, do the async checksumming */
1700 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1701 inode, rw, bio, mirror_num,
1702 bio_flags, bio_offset,
1703 __btrfs_submit_bio_start,
1704 __btrfs_submit_bio_done);
1706 } else if (!skip_sum) {
1707 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1713 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0);
1717 bio_endio(bio, ret);
1722 * given a list of ordered sums record them in the inode. This happens
1723 * at IO completion time based on sums calculated at bio submission time.
1725 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1726 struct inode *inode, u64 file_offset,
1727 struct list_head *list)
1729 struct btrfs_ordered_sum *sum;
1731 list_for_each_entry(sum, list, list) {
1732 trans->adding_csums = 1;
1733 btrfs_csum_file_blocks(trans,
1734 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1735 trans->adding_csums = 0;
1740 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1741 struct extent_state **cached_state)
1743 WARN_ON((end & (PAGE_CACHE_SIZE - 1)) == 0);
1744 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1745 cached_state, GFP_NOFS);
1748 /* see btrfs_writepage_start_hook for details on why this is required */
1749 struct btrfs_writepage_fixup {
1751 struct btrfs_work_struct work;
1754 static void btrfs_writepage_fixup_worker(struct btrfs_work_struct *work)
1756 struct btrfs_writepage_fixup *fixup;
1757 struct btrfs_ordered_extent *ordered;
1758 struct extent_state *cached_state = NULL;
1760 struct inode *inode;
1765 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1769 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1770 ClearPageChecked(page);
1774 inode = page->mapping->host;
1775 page_start = page_offset(page);
1776 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1778 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1781 /* already ordered? We're done */
1782 if (PagePrivate2(page))
1785 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1787 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1788 page_end, &cached_state, GFP_NOFS);
1790 btrfs_start_ordered_extent(inode, ordered, 1);
1791 btrfs_put_ordered_extent(ordered);
1795 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
1797 mapping_set_error(page->mapping, ret);
1798 end_extent_writepage(page, ret, page_start, page_end);
1799 ClearPageChecked(page);
1803 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1804 ClearPageChecked(page);
1805 set_page_dirty(page);
1807 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1808 &cached_state, GFP_NOFS);
1811 page_cache_release(page);
1816 * There are a few paths in the higher layers of the kernel that directly
1817 * set the page dirty bit without asking the filesystem if it is a
1818 * good idea. This causes problems because we want to make sure COW
1819 * properly happens and the data=ordered rules are followed.
1821 * In our case any range that doesn't have the ORDERED bit set
1822 * hasn't been properly setup for IO. We kick off an async process
1823 * to fix it up. The async helper will wait for ordered extents, set
1824 * the delalloc bit and make it safe to write the page.
1826 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1828 struct inode *inode = page->mapping->host;
1829 struct btrfs_writepage_fixup *fixup;
1830 struct btrfs_root *root = BTRFS_I(inode)->root;
1832 /* this page is properly in the ordered list */
1833 if (TestClearPagePrivate2(page))
1836 if (PageChecked(page))
1839 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1843 SetPageChecked(page);
1844 page_cache_get(page);
1845 btrfs_init_work(&fixup->work, btrfs_writepage_fixup_worker, NULL, NULL);
1847 btrfs_queue_work(root->fs_info->fixup_workers, &fixup->work);
1851 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1852 struct inode *inode, u64 file_pos,
1853 u64 disk_bytenr, u64 disk_num_bytes,
1854 u64 num_bytes, u64 ram_bytes,
1855 u8 compression, u8 encryption,
1856 u16 other_encoding, int extent_type)
1858 struct btrfs_root *root = BTRFS_I(inode)->root;
1859 struct btrfs_file_extent_item *fi;
1860 struct btrfs_path *path;
1861 struct extent_buffer *leaf;
1862 struct btrfs_key ins;
1863 int extent_inserted = 0;
1866 path = btrfs_alloc_path();
1871 * we may be replacing one extent in the tree with another.
1872 * The new extent is pinned in the extent map, and we don't want
1873 * to drop it from the cache until it is completely in the btree.
1875 * So, tell btrfs_drop_extents to leave this extent in the cache.
1876 * the caller is expected to unpin it and allow it to be merged
1879 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos,
1880 file_pos + num_bytes, NULL, 0,
1881 1, sizeof(*fi), &extent_inserted);
1885 if (!extent_inserted) {
1886 ins.objectid = btrfs_ino(inode);
1887 ins.offset = file_pos;
1888 ins.type = BTRFS_EXTENT_DATA_KEY;
1890 path->leave_spinning = 1;
1891 ret = btrfs_insert_empty_item(trans, root, path, &ins,
1896 leaf = path->nodes[0];
1897 fi = btrfs_item_ptr(leaf, path->slots[0],
1898 struct btrfs_file_extent_item);
1899 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1900 btrfs_set_file_extent_type(leaf, fi, extent_type);
1901 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1902 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1903 btrfs_set_file_extent_offset(leaf, fi, 0);
1904 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1905 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1906 btrfs_set_file_extent_compression(leaf, fi, compression);
1907 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1908 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1910 btrfs_mark_buffer_dirty(leaf);
1911 btrfs_release_path(path);
1913 inode_add_bytes(inode, num_bytes);
1915 ins.objectid = disk_bytenr;
1916 ins.offset = disk_num_bytes;
1917 ins.type = BTRFS_EXTENT_ITEM_KEY;
1918 ret = btrfs_alloc_reserved_file_extent(trans, root,
1919 root->root_key.objectid,
1920 btrfs_ino(inode), file_pos, &ins);
1922 btrfs_free_path(path);
1927 /* snapshot-aware defrag */
1928 struct sa_defrag_extent_backref {
1929 struct rb_node node;
1930 struct old_sa_defrag_extent *old;
1939 struct old_sa_defrag_extent {
1940 struct list_head list;
1941 struct new_sa_defrag_extent *new;
1950 struct new_sa_defrag_extent {
1951 struct rb_root root;
1952 struct list_head head;
1953 struct btrfs_path *path;
1954 struct inode *inode;
1962 static int backref_comp(struct sa_defrag_extent_backref *b1,
1963 struct sa_defrag_extent_backref *b2)
1965 if (b1->root_id < b2->root_id)
1967 else if (b1->root_id > b2->root_id)
1970 if (b1->inum < b2->inum)
1972 else if (b1->inum > b2->inum)
1975 if (b1->file_pos < b2->file_pos)
1977 else if (b1->file_pos > b2->file_pos)
1981 * [------------------------------] ===> (a range of space)
1982 * |<--->| |<---->| =============> (fs/file tree A)
1983 * |<---------------------------->| ===> (fs/file tree B)
1985 * A range of space can refer to two file extents in one tree while
1986 * refer to only one file extent in another tree.
1988 * So we may process a disk offset more than one time(two extents in A)
1989 * and locate at the same extent(one extent in B), then insert two same
1990 * backrefs(both refer to the extent in B).
1995 static void backref_insert(struct rb_root *root,
1996 struct sa_defrag_extent_backref *backref)
1998 struct rb_node **p = &root->rb_node;
1999 struct rb_node *parent = NULL;
2000 struct sa_defrag_extent_backref *entry;
2005 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
2007 ret = backref_comp(backref, entry);
2011 p = &(*p)->rb_right;
2014 rb_link_node(&backref->node, parent, p);
2015 rb_insert_color(&backref->node, root);
2019 * Note the backref might has changed, and in this case we just return 0.
2021 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2024 struct btrfs_file_extent_item *extent;
2025 struct btrfs_fs_info *fs_info;
2026 struct old_sa_defrag_extent *old = ctx;
2027 struct new_sa_defrag_extent *new = old->new;
2028 struct btrfs_path *path = new->path;
2029 struct btrfs_key key;
2030 struct btrfs_root *root;
2031 struct sa_defrag_extent_backref *backref;
2032 struct extent_buffer *leaf;
2033 struct inode *inode = new->inode;
2039 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2040 inum == btrfs_ino(inode))
2043 key.objectid = root_id;
2044 key.type = BTRFS_ROOT_ITEM_KEY;
2045 key.offset = (u64)-1;
2047 fs_info = BTRFS_I(inode)->root->fs_info;
2048 root = btrfs_read_fs_root_no_name(fs_info, &key);
2050 if (PTR_ERR(root) == -ENOENT)
2053 pr_debug("inum=%llu, offset=%llu, root_id=%llu\n",
2054 inum, offset, root_id);
2055 return PTR_ERR(root);
2058 key.objectid = inum;
2059 key.type = BTRFS_EXTENT_DATA_KEY;
2060 if (offset > (u64)-1 << 32)
2063 key.offset = offset;
2065 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2066 if (WARN_ON(ret < 0))
2073 leaf = path->nodes[0];
2074 slot = path->slots[0];
2076 if (slot >= btrfs_header_nritems(leaf)) {
2077 ret = btrfs_next_leaf(root, path);
2080 } else if (ret > 0) {
2089 btrfs_item_key_to_cpu(leaf, &key, slot);
2091 if (key.objectid > inum)
2094 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2097 extent = btrfs_item_ptr(leaf, slot,
2098 struct btrfs_file_extent_item);
2100 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2104 * 'offset' refers to the exact key.offset,
2105 * NOT the 'offset' field in btrfs_extent_data_ref, ie.
2106 * (key.offset - extent_offset).
2108 if (key.offset != offset)
2111 extent_offset = btrfs_file_extent_offset(leaf, extent);
2112 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2114 if (extent_offset >= old->extent_offset + old->offset +
2115 old->len || extent_offset + num_bytes <=
2116 old->extent_offset + old->offset)
2121 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2127 backref->root_id = root_id;
2128 backref->inum = inum;
2129 backref->file_pos = offset;
2130 backref->num_bytes = num_bytes;
2131 backref->extent_offset = extent_offset;
2132 backref->generation = btrfs_file_extent_generation(leaf, extent);
2134 backref_insert(&new->root, backref);
2137 btrfs_release_path(path);
2142 static noinline bool record_extent_backrefs(struct btrfs_path *path,
2143 struct new_sa_defrag_extent *new)
2145 struct btrfs_fs_info *fs_info = BTRFS_I(new->inode)->root->fs_info;
2146 struct old_sa_defrag_extent *old, *tmp;
2151 list_for_each_entry_safe(old, tmp, &new->head, list) {
2152 ret = iterate_inodes_from_logical(old->bytenr +
2153 old->extent_offset, fs_info,
2154 path, record_one_backref,
2156 if (ret < 0 && ret != -ENOENT)
2159 /* no backref to be processed for this extent */
2161 list_del(&old->list);
2166 if (list_empty(&new->head))
2172 static int relink_is_mergable(struct extent_buffer *leaf,
2173 struct btrfs_file_extent_item *fi,
2174 struct new_sa_defrag_extent *new)
2176 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr)
2179 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2182 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type)
2185 if (btrfs_file_extent_encryption(leaf, fi) ||
2186 btrfs_file_extent_other_encoding(leaf, fi))
2193 * Note the backref might has changed, and in this case we just return 0.
2195 static noinline int relink_extent_backref(struct btrfs_path *path,
2196 struct sa_defrag_extent_backref *prev,
2197 struct sa_defrag_extent_backref *backref)
2199 struct btrfs_file_extent_item *extent;
2200 struct btrfs_file_extent_item *item;
2201 struct btrfs_ordered_extent *ordered;
2202 struct btrfs_trans_handle *trans;
2203 struct btrfs_fs_info *fs_info;
2204 struct btrfs_root *root;
2205 struct btrfs_key key;
2206 struct extent_buffer *leaf;
2207 struct old_sa_defrag_extent *old = backref->old;
2208 struct new_sa_defrag_extent *new = old->new;
2209 struct inode *src_inode = new->inode;
2210 struct inode *inode;
2211 struct extent_state *cached = NULL;
2220 if (prev && prev->root_id == backref->root_id &&
2221 prev->inum == backref->inum &&
2222 prev->file_pos + prev->num_bytes == backref->file_pos)
2225 /* step 1: get root */
2226 key.objectid = backref->root_id;
2227 key.type = BTRFS_ROOT_ITEM_KEY;
2228 key.offset = (u64)-1;
2230 fs_info = BTRFS_I(src_inode)->root->fs_info;
2231 index = srcu_read_lock(&fs_info->subvol_srcu);
2233 root = btrfs_read_fs_root_no_name(fs_info, &key);
2235 srcu_read_unlock(&fs_info->subvol_srcu, index);
2236 if (PTR_ERR(root) == -ENOENT)
2238 return PTR_ERR(root);
2241 if (btrfs_root_readonly(root)) {
2242 srcu_read_unlock(&fs_info->subvol_srcu, index);
2246 /* step 2: get inode */
2247 key.objectid = backref->inum;
2248 key.type = BTRFS_INODE_ITEM_KEY;
2251 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2252 if (IS_ERR(inode)) {
2253 srcu_read_unlock(&fs_info->subvol_srcu, index);
2257 srcu_read_unlock(&fs_info->subvol_srcu, index);
2259 /* step 3: relink backref */
2260 lock_start = backref->file_pos;
2261 lock_end = backref->file_pos + backref->num_bytes - 1;
2262 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2265 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2267 btrfs_put_ordered_extent(ordered);
2271 trans = btrfs_join_transaction(root);
2272 if (IS_ERR(trans)) {
2273 ret = PTR_ERR(trans);
2277 key.objectid = backref->inum;
2278 key.type = BTRFS_EXTENT_DATA_KEY;
2279 key.offset = backref->file_pos;
2281 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2284 } else if (ret > 0) {
2289 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2290 struct btrfs_file_extent_item);
2292 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2293 backref->generation)
2296 btrfs_release_path(path);
2298 start = backref->file_pos;
2299 if (backref->extent_offset < old->extent_offset + old->offset)
2300 start += old->extent_offset + old->offset -
2301 backref->extent_offset;
2303 len = min(backref->extent_offset + backref->num_bytes,
2304 old->extent_offset + old->offset + old->len);
2305 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2307 ret = btrfs_drop_extents(trans, root, inode, start,
2312 key.objectid = btrfs_ino(inode);
2313 key.type = BTRFS_EXTENT_DATA_KEY;
2316 path->leave_spinning = 1;
2318 struct btrfs_file_extent_item *fi;
2320 struct btrfs_key found_key;
2322 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2327 leaf = path->nodes[0];
2328 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2330 fi = btrfs_item_ptr(leaf, path->slots[0],
2331 struct btrfs_file_extent_item);
2332 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2334 if (extent_len + found_key.offset == start &&
2335 relink_is_mergable(leaf, fi, new)) {
2336 btrfs_set_file_extent_num_bytes(leaf, fi,
2338 btrfs_mark_buffer_dirty(leaf);
2339 inode_add_bytes(inode, len);
2345 btrfs_release_path(path);
2350 ret = btrfs_insert_empty_item(trans, root, path, &key,
2353 btrfs_abort_transaction(trans, root, ret);
2357 leaf = path->nodes[0];
2358 item = btrfs_item_ptr(leaf, path->slots[0],
2359 struct btrfs_file_extent_item);
2360 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2361 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2362 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2363 btrfs_set_file_extent_num_bytes(leaf, item, len);
2364 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2365 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2366 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2367 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2368 btrfs_set_file_extent_encryption(leaf, item, 0);
2369 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2371 btrfs_mark_buffer_dirty(leaf);
2372 inode_add_bytes(inode, len);
2373 btrfs_release_path(path);
2375 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2377 backref->root_id, backref->inum,
2378 new->file_pos, 0); /* start - extent_offset */
2380 btrfs_abort_transaction(trans, root, ret);
2386 btrfs_release_path(path);
2387 path->leave_spinning = 0;
2388 btrfs_end_transaction(trans, root);
2390 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2396 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new)
2398 struct old_sa_defrag_extent *old, *tmp;
2403 list_for_each_entry_safe(old, tmp, &new->head, list) {
2404 list_del(&old->list);
2410 static void relink_file_extents(struct new_sa_defrag_extent *new)
2412 struct btrfs_path *path;
2413 struct sa_defrag_extent_backref *backref;
2414 struct sa_defrag_extent_backref *prev = NULL;
2415 struct inode *inode;
2416 struct btrfs_root *root;
2417 struct rb_node *node;
2421 root = BTRFS_I(inode)->root;
2423 path = btrfs_alloc_path();
2427 if (!record_extent_backrefs(path, new)) {
2428 btrfs_free_path(path);
2431 btrfs_release_path(path);
2434 node = rb_first(&new->root);
2437 rb_erase(node, &new->root);
2439 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2441 ret = relink_extent_backref(path, prev, backref);
2454 btrfs_free_path(path);
2456 free_sa_defrag_extent(new);
2458 atomic_dec(&root->fs_info->defrag_running);
2459 wake_up(&root->fs_info->transaction_wait);
2462 static struct new_sa_defrag_extent *
2463 record_old_file_extents(struct inode *inode,
2464 struct btrfs_ordered_extent *ordered)
2466 struct btrfs_root *root = BTRFS_I(inode)->root;
2467 struct btrfs_path *path;
2468 struct btrfs_key key;
2469 struct old_sa_defrag_extent *old;
2470 struct new_sa_defrag_extent *new;
2473 new = kmalloc(sizeof(*new), GFP_NOFS);
2478 new->file_pos = ordered->file_offset;
2479 new->len = ordered->len;
2480 new->bytenr = ordered->start;
2481 new->disk_len = ordered->disk_len;
2482 new->compress_type = ordered->compress_type;
2483 new->root = RB_ROOT;
2484 INIT_LIST_HEAD(&new->head);
2486 path = btrfs_alloc_path();
2490 key.objectid = btrfs_ino(inode);
2491 key.type = BTRFS_EXTENT_DATA_KEY;
2492 key.offset = new->file_pos;
2494 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2497 if (ret > 0 && path->slots[0] > 0)
2500 /* find out all the old extents for the file range */
2502 struct btrfs_file_extent_item *extent;
2503 struct extent_buffer *l;
2512 slot = path->slots[0];
2514 if (slot >= btrfs_header_nritems(l)) {
2515 ret = btrfs_next_leaf(root, path);
2523 btrfs_item_key_to_cpu(l, &key, slot);
2525 if (key.objectid != btrfs_ino(inode))
2527 if (key.type != BTRFS_EXTENT_DATA_KEY)
2529 if (key.offset >= new->file_pos + new->len)
2532 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2534 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2535 if (key.offset + num_bytes < new->file_pos)
2538 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2542 extent_offset = btrfs_file_extent_offset(l, extent);
2544 old = kmalloc(sizeof(*old), GFP_NOFS);
2548 offset = max(new->file_pos, key.offset);
2549 end = min(new->file_pos + new->len, key.offset + num_bytes);
2551 old->bytenr = disk_bytenr;
2552 old->extent_offset = extent_offset;
2553 old->offset = offset - key.offset;
2554 old->len = end - offset;
2557 list_add_tail(&old->list, &new->head);
2563 btrfs_free_path(path);
2564 atomic_inc(&root->fs_info->defrag_running);
2569 btrfs_free_path(path);
2571 free_sa_defrag_extent(new);
2575 /* as ordered data IO finishes, this gets called so we can finish
2576 * an ordered extent if the range of bytes in the file it covers are
2579 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2581 struct inode *inode = ordered_extent->inode;
2582 struct btrfs_root *root = BTRFS_I(inode)->root;
2583 struct btrfs_trans_handle *trans = NULL;
2584 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2585 struct extent_state *cached_state = NULL;
2586 struct new_sa_defrag_extent *new = NULL;
2587 int compress_type = 0;
2589 u64 logical_len = ordered_extent->len;
2591 bool truncated = false;
2593 nolock = btrfs_is_free_space_inode(inode);
2595 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2600 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2602 logical_len = ordered_extent->truncated_len;
2603 /* Truncated the entire extent, don't bother adding */
2608 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2609 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2610 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2612 trans = btrfs_join_transaction_nolock(root);
2614 trans = btrfs_join_transaction(root);
2615 if (IS_ERR(trans)) {
2616 ret = PTR_ERR(trans);
2620 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2621 ret = btrfs_update_inode_fallback(trans, root, inode);
2622 if (ret) /* -ENOMEM or corruption */
2623 btrfs_abort_transaction(trans, root, ret);
2627 lock_extent_bits(io_tree, ordered_extent->file_offset,
2628 ordered_extent->file_offset + ordered_extent->len - 1,
2631 ret = test_range_bit(io_tree, ordered_extent->file_offset,
2632 ordered_extent->file_offset + ordered_extent->len - 1,
2633 EXTENT_DEFRAG, 1, cached_state);
2635 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2636 if (0 && last_snapshot >= BTRFS_I(inode)->generation)
2637 /* the inode is shared */
2638 new = record_old_file_extents(inode, ordered_extent);
2640 clear_extent_bit(io_tree, ordered_extent->file_offset,
2641 ordered_extent->file_offset + ordered_extent->len - 1,
2642 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS);
2646 trans = btrfs_join_transaction_nolock(root);
2648 trans = btrfs_join_transaction(root);
2649 if (IS_ERR(trans)) {
2650 ret = PTR_ERR(trans);
2654 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2656 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
2657 compress_type = ordered_extent->compress_type;
2658 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2659 BUG_ON(compress_type);
2660 ret = btrfs_mark_extent_written(trans, inode,
2661 ordered_extent->file_offset,
2662 ordered_extent->file_offset +
2665 BUG_ON(root == root->fs_info->tree_root);
2666 ret = insert_reserved_file_extent(trans, inode,
2667 ordered_extent->file_offset,
2668 ordered_extent->start,
2669 ordered_extent->disk_len,
2670 logical_len, logical_len,
2671 compress_type, 0, 0,
2672 BTRFS_FILE_EXTENT_REG);
2674 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2675 ordered_extent->file_offset, ordered_extent->len,
2678 btrfs_abort_transaction(trans, root, ret);
2682 add_pending_csums(trans, inode, ordered_extent->file_offset,
2683 &ordered_extent->list);
2685 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2686 ret = btrfs_update_inode_fallback(trans, root, inode);
2687 if (ret) { /* -ENOMEM or corruption */
2688 btrfs_abort_transaction(trans, root, ret);
2693 unlock_extent_cached(io_tree, ordered_extent->file_offset,
2694 ordered_extent->file_offset +
2695 ordered_extent->len - 1, &cached_state, GFP_NOFS);
2697 if (root != root->fs_info->tree_root)
2698 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
2700 btrfs_end_transaction(trans, root);
2702 if (ret || truncated) {
2706 start = ordered_extent->file_offset + logical_len;
2708 start = ordered_extent->file_offset;
2709 end = ordered_extent->file_offset + ordered_extent->len - 1;
2710 clear_extent_uptodate(io_tree, start, end, NULL, GFP_NOFS);
2712 /* Drop the cache for the part of the extent we didn't write. */
2713 btrfs_drop_extent_cache(inode, start, end, 0);
2716 * If the ordered extent had an IOERR or something else went
2717 * wrong we need to return the space for this ordered extent
2718 * back to the allocator. We only free the extent in the
2719 * truncated case if we didn't write out the extent at all.
2721 if ((ret || !logical_len) &&
2722 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2723 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
2724 btrfs_free_reserved_extent(root, ordered_extent->start,
2725 ordered_extent->disk_len);
2730 * This needs to be done to make sure anybody waiting knows we are done
2731 * updating everything for this ordered extent.
2733 btrfs_remove_ordered_extent(inode, ordered_extent);
2735 /* for snapshot-aware defrag */
2738 free_sa_defrag_extent(new);
2739 atomic_dec(&root->fs_info->defrag_running);
2741 relink_file_extents(new);
2746 btrfs_put_ordered_extent(ordered_extent);
2747 /* once for the tree */
2748 btrfs_put_ordered_extent(ordered_extent);
2753 static void finish_ordered_fn(struct btrfs_work_struct *work)
2755 struct btrfs_ordered_extent *ordered_extent;
2756 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2757 btrfs_finish_ordered_io(ordered_extent);
2760 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
2761 struct extent_state *state, int uptodate)
2763 struct inode *inode = page->mapping->host;
2764 struct btrfs_root *root = BTRFS_I(inode)->root;
2765 struct btrfs_ordered_extent *ordered_extent = NULL;
2766 struct btrfs_workqueue_struct *workers;
2768 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2770 ClearPagePrivate2(page);
2771 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2772 end - start + 1, uptodate))
2775 btrfs_init_work(&ordered_extent->work, finish_ordered_fn, NULL, NULL);
2777 if (btrfs_is_free_space_inode(inode))
2778 workers = root->fs_info->endio_freespace_worker;
2780 workers = root->fs_info->endio_write_workers;
2781 btrfs_queue_work(workers, &ordered_extent->work);
2787 * when reads are done, we need to check csums to verify the data is correct
2788 * if there's a match, we allow the bio to finish. If not, the code in
2789 * extent_io.c will try to find good copies for us.
2791 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
2792 u64 phy_offset, struct page *page,
2793 u64 start, u64 end, int mirror)
2795 size_t offset = start - page_offset(page);
2796 struct inode *inode = page->mapping->host;
2797 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2799 struct btrfs_root *root = BTRFS_I(inode)->root;
2802 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
2803 DEFAULT_RATELIMIT_BURST);
2805 if (PageChecked(page)) {
2806 ClearPageChecked(page);
2810 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
2813 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
2814 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
2815 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
2820 phy_offset >>= inode->i_sb->s_blocksize_bits;
2821 csum_expected = *(((u32 *)io_bio->csum) + phy_offset);
2823 kaddr = kmap_atomic(page);
2824 csum = btrfs_csum_data(kaddr + offset, csum, end - start + 1);
2825 btrfs_csum_final(csum, (char *)&csum);
2826 if (csum != csum_expected)
2829 kunmap_atomic(kaddr);
2834 if (__ratelimit(&_rs))
2835 btrfs_info(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
2836 btrfs_ino(page->mapping->host), start, csum, csum_expected);
2837 memset(kaddr + offset, 1, end - start + 1);
2838 flush_dcache_page(page);
2839 kunmap_atomic(kaddr);
2840 if (csum_expected == 0)
2845 struct delayed_iput {
2846 struct list_head list;
2847 struct inode *inode;
2850 /* JDM: If this is fs-wide, why can't we add a pointer to
2851 * btrfs_inode instead and avoid the allocation? */
2852 void btrfs_add_delayed_iput(struct inode *inode)
2854 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2855 struct delayed_iput *delayed;
2857 if (atomic_add_unless(&inode->i_count, -1, 1))
2860 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2861 delayed->inode = inode;
2863 spin_lock(&fs_info->delayed_iput_lock);
2864 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2865 spin_unlock(&fs_info->delayed_iput_lock);
2868 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2871 struct btrfs_fs_info *fs_info = root->fs_info;
2872 struct delayed_iput *delayed;
2875 spin_lock(&fs_info->delayed_iput_lock);
2876 empty = list_empty(&fs_info->delayed_iputs);
2877 spin_unlock(&fs_info->delayed_iput_lock);
2881 spin_lock(&fs_info->delayed_iput_lock);
2882 list_splice_init(&fs_info->delayed_iputs, &list);
2883 spin_unlock(&fs_info->delayed_iput_lock);
2885 while (!list_empty(&list)) {
2886 delayed = list_entry(list.next, struct delayed_iput, list);
2887 list_del(&delayed->list);
2888 iput(delayed->inode);
2894 * This is called in transaction commit time. If there are no orphan
2895 * files in the subvolume, it removes orphan item and frees block_rsv
2898 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2899 struct btrfs_root *root)
2901 struct btrfs_block_rsv *block_rsv;
2904 if (atomic_read(&root->orphan_inodes) ||
2905 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2908 spin_lock(&root->orphan_lock);
2909 if (atomic_read(&root->orphan_inodes)) {
2910 spin_unlock(&root->orphan_lock);
2914 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) {
2915 spin_unlock(&root->orphan_lock);
2919 block_rsv = root->orphan_block_rsv;
2920 root->orphan_block_rsv = NULL;
2921 spin_unlock(&root->orphan_lock);
2923 if (root->orphan_item_inserted &&
2924 btrfs_root_refs(&root->root_item) > 0) {
2925 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2926 root->root_key.objectid);
2928 btrfs_abort_transaction(trans, root, ret);
2930 root->orphan_item_inserted = 0;
2934 WARN_ON(block_rsv->size > 0);
2935 btrfs_free_block_rsv(root, block_rsv);
2940 * This creates an orphan entry for the given inode in case something goes
2941 * wrong in the middle of an unlink/truncate.
2943 * NOTE: caller of this function should reserve 5 units of metadata for
2946 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2948 struct btrfs_root *root = BTRFS_I(inode)->root;
2949 struct btrfs_block_rsv *block_rsv = NULL;
2954 if (!root->orphan_block_rsv) {
2955 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
2960 spin_lock(&root->orphan_lock);
2961 if (!root->orphan_block_rsv) {
2962 root->orphan_block_rsv = block_rsv;
2963 } else if (block_rsv) {
2964 btrfs_free_block_rsv(root, block_rsv);
2968 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2969 &BTRFS_I(inode)->runtime_flags)) {
2972 * For proper ENOSPC handling, we should do orphan
2973 * cleanup when mounting. But this introduces backward
2974 * compatibility issue.
2976 if (!xchg(&root->orphan_item_inserted, 1))
2982 atomic_inc(&root->orphan_inodes);
2985 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2986 &BTRFS_I(inode)->runtime_flags))
2988 spin_unlock(&root->orphan_lock);
2990 /* grab metadata reservation from transaction handle */
2992 ret = btrfs_orphan_reserve_metadata(trans, inode);
2993 BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */
2996 /* insert an orphan item to track this unlinked/truncated file */
2998 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
3000 atomic_dec(&root->orphan_inodes);
3002 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3003 &BTRFS_I(inode)->runtime_flags);
3004 btrfs_orphan_release_metadata(inode);
3006 if (ret != -EEXIST) {
3007 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3008 &BTRFS_I(inode)->runtime_flags);
3009 btrfs_abort_transaction(trans, root, ret);
3016 /* insert an orphan item to track subvolume contains orphan files */
3018 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
3019 root->root_key.objectid);
3020 if (ret && ret != -EEXIST) {
3021 btrfs_abort_transaction(trans, root, ret);
3029 * We have done the truncate/delete so we can go ahead and remove the orphan
3030 * item for this particular inode.
3032 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3033 struct inode *inode)
3035 struct btrfs_root *root = BTRFS_I(inode)->root;
3036 int delete_item = 0;
3037 int release_rsv = 0;
3040 spin_lock(&root->orphan_lock);
3041 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3042 &BTRFS_I(inode)->runtime_flags))
3045 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3046 &BTRFS_I(inode)->runtime_flags))
3048 spin_unlock(&root->orphan_lock);
3051 atomic_dec(&root->orphan_inodes);
3053 ret = btrfs_del_orphan_item(trans, root,
3058 btrfs_orphan_release_metadata(inode);
3064 * this cleans up any orphans that may be left on the list from the last use
3067 int btrfs_orphan_cleanup(struct btrfs_root *root)
3069 struct btrfs_path *path;
3070 struct extent_buffer *leaf;
3071 struct btrfs_key key, found_key;
3072 struct btrfs_trans_handle *trans;
3073 struct inode *inode;
3074 u64 last_objectid = 0;
3075 int ret = 0, nr_unlink = 0, nr_truncate = 0;
3077 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3080 path = btrfs_alloc_path();
3087 key.objectid = BTRFS_ORPHAN_OBJECTID;
3088 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
3089 key.offset = (u64)-1;
3092 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3097 * if ret == 0 means we found what we were searching for, which
3098 * is weird, but possible, so only screw with path if we didn't
3099 * find the key and see if we have stuff that matches
3103 if (path->slots[0] == 0)
3108 /* pull out the item */
3109 leaf = path->nodes[0];
3110 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3112 /* make sure the item matches what we want */
3113 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3115 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
3118 /* release the path since we're done with it */
3119 btrfs_release_path(path);
3122 * this is where we are basically btrfs_lookup, without the
3123 * crossing root thing. we store the inode number in the
3124 * offset of the orphan item.
3127 if (found_key.offset == last_objectid) {
3128 btrfs_err(root->fs_info,
3129 "Error removing orphan entry, stopping orphan cleanup");
3134 last_objectid = found_key.offset;
3136 found_key.objectid = found_key.offset;
3137 found_key.type = BTRFS_INODE_ITEM_KEY;
3138 found_key.offset = 0;
3139 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
3140 ret = PTR_ERR_OR_ZERO(inode);
3141 if (ret && ret != -ESTALE)
3144 if (ret == -ESTALE && root == root->fs_info->tree_root) {
3145 struct btrfs_root *dead_root;
3146 struct btrfs_fs_info *fs_info = root->fs_info;
3147 int is_dead_root = 0;
3150 * this is an orphan in the tree root. Currently these
3151 * could come from 2 sources:
3152 * a) a snapshot deletion in progress
3153 * b) a free space cache inode
3154 * We need to distinguish those two, as the snapshot
3155 * orphan must not get deleted.
3156 * find_dead_roots already ran before us, so if this
3157 * is a snapshot deletion, we should find the root
3158 * in the dead_roots list
3160 spin_lock(&fs_info->trans_lock);
3161 list_for_each_entry(dead_root, &fs_info->dead_roots,
3163 if (dead_root->root_key.objectid ==
3164 found_key.objectid) {
3169 spin_unlock(&fs_info->trans_lock);
3171 /* prevent this orphan from being found again */
3172 key.offset = found_key.objectid - 1;
3177 * Inode is already gone but the orphan item is still there,
3178 * kill the orphan item.
3180 if (ret == -ESTALE) {
3181 trans = btrfs_start_transaction(root, 1);
3182 if (IS_ERR(trans)) {
3183 ret = PTR_ERR(trans);
3186 btrfs_debug(root->fs_info, "auto deleting %Lu",
3187 found_key.objectid);
3188 ret = btrfs_del_orphan_item(trans, root,
3189 found_key.objectid);
3190 btrfs_end_transaction(trans, root);
3197 * add this inode to the orphan list so btrfs_orphan_del does
3198 * the proper thing when we hit it
3200 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3201 &BTRFS_I(inode)->runtime_flags);
3202 atomic_inc(&root->orphan_inodes);
3204 /* if we have links, this was a truncate, lets do that */
3205 if (inode->i_nlink) {
3206 if (WARN_ON(!S_ISREG(inode->i_mode))) {
3212 /* 1 for the orphan item deletion. */
3213 trans = btrfs_start_transaction(root, 1);
3214 if (IS_ERR(trans)) {
3216 ret = PTR_ERR(trans);
3219 ret = btrfs_orphan_add(trans, inode);
3220 btrfs_end_transaction(trans, root);
3226 ret = btrfs_truncate(inode);
3228 btrfs_orphan_del(NULL, inode);
3233 /* this will do delete_inode and everything for us */
3238 /* release the path since we're done with it */
3239 btrfs_release_path(path);
3241 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3243 if (root->orphan_block_rsv)
3244 btrfs_block_rsv_release(root, root->orphan_block_rsv,
3247 if (root->orphan_block_rsv || root->orphan_item_inserted) {
3248 trans = btrfs_join_transaction(root);
3250 btrfs_end_transaction(trans, root);
3254 btrfs_debug(root->fs_info, "unlinked %d orphans", nr_unlink);
3256 btrfs_debug(root->fs_info, "truncated %d orphans", nr_truncate);
3260 btrfs_crit(root->fs_info,
3261 "could not do orphan cleanup %d", ret);
3262 btrfs_free_path(path);
3267 * very simple check to peek ahead in the leaf looking for xattrs. If we
3268 * don't find any xattrs, we know there can't be any acls.
3270 * slot is the slot the inode is in, objectid is the objectid of the inode
3272 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3273 int slot, u64 objectid,
3274 int *first_xattr_slot)
3276 u32 nritems = btrfs_header_nritems(leaf);
3277 struct btrfs_key found_key;
3278 static u64 xattr_access = 0;
3279 static u64 xattr_default = 0;
3282 if (!xattr_access) {
3283 xattr_access = btrfs_name_hash(POSIX_ACL_XATTR_ACCESS,
3284 strlen(POSIX_ACL_XATTR_ACCESS));
3285 xattr_default = btrfs_name_hash(POSIX_ACL_XATTR_DEFAULT,
3286 strlen(POSIX_ACL_XATTR_DEFAULT));
3290 *first_xattr_slot = -1;
3291 while (slot < nritems) {
3292 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3294 /* we found a different objectid, there must not be acls */
3295 if (found_key.objectid != objectid)
3298 /* we found an xattr, assume we've got an acl */
3299 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3300 if (*first_xattr_slot == -1)
3301 *first_xattr_slot = slot;
3302 if (found_key.offset == xattr_access ||
3303 found_key.offset == xattr_default)
3308 * we found a key greater than an xattr key, there can't
3309 * be any acls later on
3311 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3318 * it goes inode, inode backrefs, xattrs, extents,
3319 * so if there are a ton of hard links to an inode there can
3320 * be a lot of backrefs. Don't waste time searching too hard,
3321 * this is just an optimization
3326 /* we hit the end of the leaf before we found an xattr or
3327 * something larger than an xattr. We have to assume the inode
3330 if (*first_xattr_slot == -1)
3331 *first_xattr_slot = slot;
3336 * read an inode from the btree into the in-memory inode
3338 static void btrfs_read_locked_inode(struct inode *inode)
3340 struct btrfs_path *path;
3341 struct extent_buffer *leaf;
3342 struct btrfs_inode_item *inode_item;
3343 struct btrfs_timespec *tspec;
3344 struct btrfs_root *root = BTRFS_I(inode)->root;
3345 struct btrfs_key location;
3350 bool filled = false;
3351 int first_xattr_slot;
3353 ret = btrfs_fill_inode(inode, &rdev);
3357 path = btrfs_alloc_path();
3361 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3363 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3367 leaf = path->nodes[0];
3372 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3373 struct btrfs_inode_item);
3374 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3375 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3376 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3377 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3378 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
3380 tspec = btrfs_inode_atime(inode_item);
3381 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3382 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3384 tspec = btrfs_inode_mtime(inode_item);
3385 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3386 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3388 tspec = btrfs_inode_ctime(inode_item);
3389 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3390 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3392 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3393 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3394 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3397 * If we were modified in the current generation and evicted from memory
3398 * and then re-read we need to do a full sync since we don't have any
3399 * idea about which extents were modified before we were evicted from
3402 if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
3403 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3404 &BTRFS_I(inode)->runtime_flags);
3406 inode->i_version = btrfs_inode_sequence(leaf, inode_item);
3407 inode->i_generation = BTRFS_I(inode)->generation;
3409 rdev = btrfs_inode_rdev(leaf, inode_item);
3411 BTRFS_I(inode)->index_cnt = (u64)-1;
3412 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3416 if (inode->i_nlink != 1 ||
3417 path->slots[0] >= btrfs_header_nritems(leaf))
3420 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]);
3421 if (location.objectid != btrfs_ino(inode))
3424 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
3425 if (location.type == BTRFS_INODE_REF_KEY) {
3426 struct btrfs_inode_ref *ref;
3428 ref = (struct btrfs_inode_ref *)ptr;
3429 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref);
3430 } else if (location.type == BTRFS_INODE_EXTREF_KEY) {
3431 struct btrfs_inode_extref *extref;
3433 extref = (struct btrfs_inode_extref *)ptr;
3434 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf,
3439 * try to precache a NULL acl entry for files that don't have
3440 * any xattrs or acls
3442 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3443 btrfs_ino(inode), &first_xattr_slot);
3444 if (first_xattr_slot != -1) {
3445 path->slots[0] = first_xattr_slot;
3446 ret = btrfs_load_inode_props(inode, path);
3448 btrfs_err(root->fs_info,
3449 "error loading props for ino %llu (root %llu): %d\n",
3451 root->root_key.objectid, ret);
3453 btrfs_free_path(path);
3456 cache_no_acl(inode);
3458 switch (inode->i_mode & S_IFMT) {
3460 inode->i_mapping->a_ops = &btrfs_aops;
3461 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3462 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3463 inode->i_fop = &btrfs_file_operations;
3464 inode->i_op = &btrfs_file_inode_operations;
3467 inode->i_fop = &btrfs_dir_file_operations;
3468 if (root == root->fs_info->tree_root)
3469 inode->i_op = &btrfs_dir_ro_inode_operations;
3471 inode->i_op = &btrfs_dir_inode_operations;
3474 inode->i_op = &btrfs_symlink_inode_operations;
3475 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3476 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3479 inode->i_op = &btrfs_special_inode_operations;
3480 init_special_inode(inode, inode->i_mode, rdev);
3484 btrfs_update_iflags(inode);
3488 btrfs_free_path(path);
3489 make_bad_inode(inode);
3493 * given a leaf and an inode, copy the inode fields into the leaf
3495 static void fill_inode_item(struct btrfs_trans_handle *trans,
3496 struct extent_buffer *leaf,
3497 struct btrfs_inode_item *item,
3498 struct inode *inode)
3500 struct btrfs_map_token token;
3502 btrfs_init_map_token(&token);
3504 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3505 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3506 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3508 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3509 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3511 btrfs_set_token_timespec_sec(leaf, btrfs_inode_atime(item),
3512 inode->i_atime.tv_sec, &token);
3513 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_atime(item),
3514 inode->i_atime.tv_nsec, &token);
3516 btrfs_set_token_timespec_sec(leaf, btrfs_inode_mtime(item),
3517 inode->i_mtime.tv_sec, &token);
3518 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_mtime(item),
3519 inode->i_mtime.tv_nsec, &token);
3521 btrfs_set_token_timespec_sec(leaf, btrfs_inode_ctime(item),
3522 inode->i_ctime.tv_sec, &token);
3523 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_ctime(item),
3524 inode->i_ctime.tv_nsec, &token);
3526 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3528 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3530 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token);
3531 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3532 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3533 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3534 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3538 * copy everything in the in-memory inode into the btree.
3540 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3541 struct btrfs_root *root, struct inode *inode)
3543 struct btrfs_inode_item *inode_item;
3544 struct btrfs_path *path;
3545 struct extent_buffer *leaf;
3548 path = btrfs_alloc_path();
3552 path->leave_spinning = 1;
3553 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3561 leaf = path->nodes[0];
3562 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3563 struct btrfs_inode_item);
3565 fill_inode_item(trans, leaf, inode_item, inode);
3566 btrfs_mark_buffer_dirty(leaf);
3567 btrfs_set_inode_last_trans(trans, inode);
3570 btrfs_free_path(path);
3575 * copy everything in the in-memory inode into the btree.
3577 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3578 struct btrfs_root *root, struct inode *inode)
3583 * If the inode is a free space inode, we can deadlock during commit
3584 * if we put it into the delayed code.
3586 * The data relocation inode should also be directly updated
3589 if (!btrfs_is_free_space_inode(inode)
3590 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
3591 btrfs_update_root_times(trans, root);
3593 ret = btrfs_delayed_update_inode(trans, root, inode);
3595 btrfs_set_inode_last_trans(trans, inode);
3599 return btrfs_update_inode_item(trans, root, inode);
3602 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3603 struct btrfs_root *root,
3604 struct inode *inode)
3608 ret = btrfs_update_inode(trans, root, inode);
3610 return btrfs_update_inode_item(trans, root, inode);
3615 * unlink helper that gets used here in inode.c and in the tree logging
3616 * recovery code. It remove a link in a directory with a given name, and
3617 * also drops the back refs in the inode to the directory
3619 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3620 struct btrfs_root *root,
3621 struct inode *dir, struct inode *inode,
3622 const char *name, int name_len)
3624 struct btrfs_path *path;
3626 struct extent_buffer *leaf;
3627 struct btrfs_dir_item *di;
3628 struct btrfs_key key;
3630 u64 ino = btrfs_ino(inode);
3631 u64 dir_ino = btrfs_ino(dir);
3633 path = btrfs_alloc_path();
3639 path->leave_spinning = 1;
3640 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3641 name, name_len, -1);
3650 leaf = path->nodes[0];
3651 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3652 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3655 btrfs_release_path(path);
3658 * If we don't have dir index, we have to get it by looking up
3659 * the inode ref, since we get the inode ref, remove it directly,
3660 * it is unnecessary to do delayed deletion.
3662 * But if we have dir index, needn't search inode ref to get it.
3663 * Since the inode ref is close to the inode item, it is better
3664 * that we delay to delete it, and just do this deletion when
3665 * we update the inode item.
3667 if (BTRFS_I(inode)->dir_index) {
3668 ret = btrfs_delayed_delete_inode_ref(inode);
3670 index = BTRFS_I(inode)->dir_index;
3675 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3678 btrfs_info(root->fs_info,
3679 "failed to delete reference to %.*s, inode %llu parent %llu",
3680 name_len, name, ino, dir_ino);
3681 btrfs_abort_transaction(trans, root, ret);
3685 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3687 btrfs_abort_transaction(trans, root, ret);
3691 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
3693 if (ret != 0 && ret != -ENOENT) {
3694 btrfs_abort_transaction(trans, root, ret);
3698 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
3703 btrfs_abort_transaction(trans, root, ret);
3705 btrfs_free_path(path);
3709 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3710 inode_inc_iversion(inode);
3711 inode_inc_iversion(dir);
3712 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3713 ret = btrfs_update_inode(trans, root, dir);
3718 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3719 struct btrfs_root *root,
3720 struct inode *dir, struct inode *inode,
3721 const char *name, int name_len)
3724 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3727 ret = btrfs_update_inode(trans, root, inode);
3733 * helper to start transaction for unlink and rmdir.
3735 * unlink and rmdir are special in btrfs, they do not always free space, so
3736 * if we cannot make our reservations the normal way try and see if there is
3737 * plenty of slack room in the global reserve to migrate, otherwise we cannot
3738 * allow the unlink to occur.
3740 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
3742 struct btrfs_trans_handle *trans;
3743 struct btrfs_root *root = BTRFS_I(dir)->root;
3747 * 1 for the possible orphan item
3748 * 1 for the dir item
3749 * 1 for the dir index
3750 * 1 for the inode ref
3753 trans = btrfs_start_transaction(root, 5);
3754 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
3757 if (PTR_ERR(trans) == -ENOSPC) {
3758 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3760 trans = btrfs_start_transaction(root, 0);
3763 ret = btrfs_cond_migrate_bytes(root->fs_info,
3764 &root->fs_info->trans_block_rsv,
3767 btrfs_end_transaction(trans, root);
3768 return ERR_PTR(ret);
3770 trans->block_rsv = &root->fs_info->trans_block_rsv;
3771 trans->bytes_reserved = num_bytes;
3776 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3778 struct btrfs_root *root = BTRFS_I(dir)->root;
3779 struct btrfs_trans_handle *trans;
3780 struct inode *inode = dentry->d_inode;
3783 trans = __unlink_start_trans(dir);
3785 return PTR_ERR(trans);
3787 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3789 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3790 dentry->d_name.name, dentry->d_name.len);
3794 if (inode->i_nlink == 0) {
3795 ret = btrfs_orphan_add(trans, inode);
3801 btrfs_end_transaction(trans, root);
3802 btrfs_btree_balance_dirty(root);
3806 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3807 struct btrfs_root *root,
3808 struct inode *dir, u64 objectid,
3809 const char *name, int name_len)
3811 struct btrfs_path *path;
3812 struct extent_buffer *leaf;
3813 struct btrfs_dir_item *di;
3814 struct btrfs_key key;
3817 u64 dir_ino = btrfs_ino(dir);
3819 path = btrfs_alloc_path();
3823 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3824 name, name_len, -1);
3825 if (IS_ERR_OR_NULL(di)) {
3833 leaf = path->nodes[0];
3834 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3835 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3836 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3838 btrfs_abort_transaction(trans, root, ret);
3841 btrfs_release_path(path);
3843 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3844 objectid, root->root_key.objectid,
3845 dir_ino, &index, name, name_len);
3847 if (ret != -ENOENT) {
3848 btrfs_abort_transaction(trans, root, ret);
3851 di = btrfs_search_dir_index_item(root, path, dir_ino,
3853 if (IS_ERR_OR_NULL(di)) {
3858 btrfs_abort_transaction(trans, root, ret);
3862 leaf = path->nodes[0];
3863 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3864 btrfs_release_path(path);
3867 btrfs_release_path(path);
3869 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3871 btrfs_abort_transaction(trans, root, ret);
3875 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3876 inode_inc_iversion(dir);
3877 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3878 ret = btrfs_update_inode_fallback(trans, root, dir);
3880 btrfs_abort_transaction(trans, root, ret);
3882 btrfs_free_path(path);
3886 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3888 struct inode *inode = dentry->d_inode;
3890 struct btrfs_root *root = BTRFS_I(dir)->root;
3891 struct btrfs_trans_handle *trans;
3893 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
3895 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3898 trans = __unlink_start_trans(dir);
3900 return PTR_ERR(trans);
3902 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3903 err = btrfs_unlink_subvol(trans, root, dir,
3904 BTRFS_I(inode)->location.objectid,
3905 dentry->d_name.name,
3906 dentry->d_name.len);
3910 err = btrfs_orphan_add(trans, inode);
3914 /* now the directory is empty */
3915 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3916 dentry->d_name.name, dentry->d_name.len);
3918 btrfs_i_size_write(inode, 0);
3920 btrfs_end_transaction(trans, root);
3921 btrfs_btree_balance_dirty(root);
3927 * this can truncate away extent items, csum items and directory items.
3928 * It starts at a high offset and removes keys until it can't find
3929 * any higher than new_size
3931 * csum items that cross the new i_size are truncated to the new size
3934 * min_type is the minimum key type to truncate down to. If set to 0, this
3935 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3937 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3938 struct btrfs_root *root,
3939 struct inode *inode,
3940 u64 new_size, u32 min_type)
3942 struct btrfs_path *path;
3943 struct extent_buffer *leaf;
3944 struct btrfs_file_extent_item *fi;
3945 struct btrfs_key key;
3946 struct btrfs_key found_key;
3947 u64 extent_start = 0;
3948 u64 extent_num_bytes = 0;
3949 u64 extent_offset = 0;
3951 u64 last_size = (u64)-1;
3952 u32 found_type = (u8)-1;
3955 int pending_del_nr = 0;
3956 int pending_del_slot = 0;
3957 int extent_type = -1;
3960 u64 ino = btrfs_ino(inode);
3962 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3964 path = btrfs_alloc_path();
3970 * We want to drop from the next block forward in case this new size is
3971 * not block aligned since we will be keeping the last block of the
3972 * extent just the way it is.
3974 if (root->ref_cows || root == root->fs_info->tree_root)
3975 btrfs_drop_extent_cache(inode, ALIGN(new_size,
3976 root->sectorsize), (u64)-1, 0);
3979 * This function is also used to drop the items in the log tree before
3980 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3981 * it is used to drop the loged items. So we shouldn't kill the delayed
3984 if (min_type == 0 && root == BTRFS_I(inode)->root)
3985 btrfs_kill_delayed_inode_items(inode);
3988 key.offset = (u64)-1;
3992 path->leave_spinning = 1;
3993 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
4000 /* there are no items in the tree for us to truncate, we're
4003 if (path->slots[0] == 0)
4010 leaf = path->nodes[0];
4011 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4012 found_type = btrfs_key_type(&found_key);
4014 if (found_key.objectid != ino)
4017 if (found_type < min_type)
4020 item_end = found_key.offset;
4021 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4022 fi = btrfs_item_ptr(leaf, path->slots[0],
4023 struct btrfs_file_extent_item);
4024 extent_type = btrfs_file_extent_type(leaf, fi);
4025 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4027 btrfs_file_extent_num_bytes(leaf, fi);
4028 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4029 item_end += btrfs_file_extent_inline_len(leaf,
4030 path->slots[0], fi);
4034 if (found_type > min_type) {
4037 if (item_end < new_size)
4039 if (found_key.offset >= new_size)
4045 /* FIXME, shrink the extent if the ref count is only 1 */
4046 if (found_type != BTRFS_EXTENT_DATA_KEY)
4050 last_size = found_key.offset;
4052 last_size = new_size;
4054 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4056 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4058 u64 orig_num_bytes =
4059 btrfs_file_extent_num_bytes(leaf, fi);
4060 extent_num_bytes = ALIGN(new_size -
4063 btrfs_set_file_extent_num_bytes(leaf, fi,
4065 num_dec = (orig_num_bytes -
4067 if (root->ref_cows && extent_start != 0)
4068 inode_sub_bytes(inode, num_dec);
4069 btrfs_mark_buffer_dirty(leaf);
4072 btrfs_file_extent_disk_num_bytes(leaf,
4074 extent_offset = found_key.offset -
4075 btrfs_file_extent_offset(leaf, fi);
4077 /* FIXME blocksize != 4096 */
4078 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4079 if (extent_start != 0) {
4082 inode_sub_bytes(inode, num_dec);
4085 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4087 * we can't truncate inline items that have had
4091 btrfs_file_extent_compression(leaf, fi) == 0 &&
4092 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4093 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
4094 u32 size = new_size - found_key.offset;
4096 if (root->ref_cows) {
4097 inode_sub_bytes(inode, item_end + 1 -
4102 * update the ram bytes to properly reflect
4103 * the new size of our item
4105 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
4107 btrfs_file_extent_calc_inline_size(size);
4108 btrfs_truncate_item(root, path, size, 1);
4109 } else if (root->ref_cows) {
4110 inode_sub_bytes(inode, item_end + 1 -
4116 if (!pending_del_nr) {
4117 /* no pending yet, add ourselves */
4118 pending_del_slot = path->slots[0];
4120 } else if (pending_del_nr &&
4121 path->slots[0] + 1 == pending_del_slot) {
4122 /* hop on the pending chunk */
4124 pending_del_slot = path->slots[0];
4131 if (found_extent && (root->ref_cows ||
4132 root == root->fs_info->tree_root)) {
4133 btrfs_set_path_blocking(path);
4134 ret = btrfs_free_extent(trans, root, extent_start,
4135 extent_num_bytes, 0,
4136 btrfs_header_owner(leaf),
4137 ino, extent_offset, 0);
4141 if (found_type == BTRFS_INODE_ITEM_KEY)
4144 if (path->slots[0] == 0 ||
4145 path->slots[0] != pending_del_slot) {
4146 if (pending_del_nr) {
4147 ret = btrfs_del_items(trans, root, path,
4151 btrfs_abort_transaction(trans,
4157 btrfs_release_path(path);
4164 if (pending_del_nr) {
4165 ret = btrfs_del_items(trans, root, path, pending_del_slot,
4168 btrfs_abort_transaction(trans, root, ret);
4171 if (last_size != (u64)-1)
4172 btrfs_ordered_update_i_size(inode, last_size, NULL);
4173 btrfs_free_path(path);
4178 * btrfs_truncate_page - read, zero a chunk and write a page
4179 * @inode - inode that we're zeroing
4180 * @from - the offset to start zeroing
4181 * @len - the length to zero, 0 to zero the entire range respective to the
4183 * @front - zero up to the offset instead of from the offset on
4185 * This will find the page for the "from" offset and cow the page and zero the
4186 * part we want to zero. This is used with truncate and hole punching.
4188 int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
4191 struct address_space *mapping = inode->i_mapping;
4192 struct btrfs_root *root = BTRFS_I(inode)->root;
4193 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4194 struct btrfs_ordered_extent *ordered;
4195 struct extent_state *cached_state = NULL;
4197 u32 blocksize = root->sectorsize;
4198 pgoff_t index = from >> PAGE_CACHE_SHIFT;
4199 unsigned offset = from & (PAGE_CACHE_SIZE-1);
4201 gfp_t mask = btrfs_alloc_write_mask(mapping);
4206 if ((offset & (blocksize - 1)) == 0 &&
4207 (!len || ((len & (blocksize - 1)) == 0)))
4209 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
4214 page = find_or_create_page(mapping, index, mask);
4216 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4221 page_start = page_offset(page);
4222 page_end = page_start + PAGE_CACHE_SIZE - 1;
4224 if (!PageUptodate(page)) {
4225 ret = btrfs_readpage(NULL, page);
4227 if (page->mapping != mapping) {
4229 page_cache_release(page);
4232 if (!PageUptodate(page)) {
4237 wait_on_page_writeback(page);
4239 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
4240 set_page_extent_mapped(page);
4242 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4244 unlock_extent_cached(io_tree, page_start, page_end,
4245 &cached_state, GFP_NOFS);
4247 page_cache_release(page);
4248 btrfs_start_ordered_extent(inode, ordered, 1);
4249 btrfs_put_ordered_extent(ordered);
4253 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
4254 EXTENT_DIRTY | EXTENT_DELALLOC |
4255 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4256 0, 0, &cached_state, GFP_NOFS);
4258 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
4261 unlock_extent_cached(io_tree, page_start, page_end,
4262 &cached_state, GFP_NOFS);
4266 if (offset != PAGE_CACHE_SIZE) {
4268 len = PAGE_CACHE_SIZE - offset;
4271 memset(kaddr, 0, offset);
4273 memset(kaddr + offset, 0, len);
4274 flush_dcache_page(page);
4277 ClearPageChecked(page);
4278 set_page_dirty(page);
4279 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
4284 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4286 page_cache_release(page);
4291 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4292 u64 offset, u64 len)
4294 struct btrfs_trans_handle *trans;
4298 * Still need to make sure the inode looks like it's been updated so
4299 * that any holes get logged if we fsync.
4301 if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) {
4302 BTRFS_I(inode)->last_trans = root->fs_info->generation;
4303 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4304 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4309 * 1 - for the one we're dropping
4310 * 1 - for the one we're adding
4311 * 1 - for updating the inode.
4313 trans = btrfs_start_transaction(root, 3);
4315 return PTR_ERR(trans);
4317 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4319 btrfs_abort_transaction(trans, root, ret);
4320 btrfs_end_transaction(trans, root);
4324 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset,
4325 0, 0, len, 0, len, 0, 0, 0);
4327 btrfs_abort_transaction(trans, root, ret);
4329 btrfs_update_inode(trans, root, inode);
4330 btrfs_end_transaction(trans, root);
4335 * This function puts in dummy file extents for the area we're creating a hole
4336 * for. So if we are truncating this file to a larger size we need to insert
4337 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4338 * the range between oldsize and size
4340 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4342 struct btrfs_root *root = BTRFS_I(inode)->root;
4343 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4344 struct extent_map *em = NULL;
4345 struct extent_state *cached_state = NULL;
4346 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4347 u64 hole_start = ALIGN(oldsize, root->sectorsize);
4348 u64 block_end = ALIGN(size, root->sectorsize);
4355 * If our size started in the middle of a page we need to zero out the
4356 * rest of the page before we expand the i_size, otherwise we could
4357 * expose stale data.
4359 err = btrfs_truncate_page(inode, oldsize, 0, 0);
4363 if (size <= hole_start)
4367 struct btrfs_ordered_extent *ordered;
4369 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
4371 ordered = btrfs_lookup_ordered_range(inode, hole_start,
4372 block_end - hole_start);
4375 unlock_extent_cached(io_tree, hole_start, block_end - 1,
4376 &cached_state, GFP_NOFS);
4377 btrfs_start_ordered_extent(inode, ordered, 1);
4378 btrfs_put_ordered_extent(ordered);
4381 cur_offset = hole_start;
4383 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
4384 block_end - cur_offset, 0);
4390 last_byte = min(extent_map_end(em), block_end);
4391 last_byte = ALIGN(last_byte , root->sectorsize);
4392 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
4393 struct extent_map *hole_em;
4394 hole_size = last_byte - cur_offset;
4396 err = maybe_insert_hole(root, inode, cur_offset,
4400 btrfs_drop_extent_cache(inode, cur_offset,
4401 cur_offset + hole_size - 1, 0);
4402 hole_em = alloc_extent_map();
4404 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4405 &BTRFS_I(inode)->runtime_flags);
4408 hole_em->start = cur_offset;
4409 hole_em->len = hole_size;
4410 hole_em->orig_start = cur_offset;
4412 hole_em->block_start = EXTENT_MAP_HOLE;
4413 hole_em->block_len = 0;
4414 hole_em->orig_block_len = 0;
4415 hole_em->ram_bytes = hole_size;
4416 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
4417 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4418 hole_em->generation = root->fs_info->generation;
4421 write_lock(&em_tree->lock);
4422 err = add_extent_mapping(em_tree, hole_em, 1);
4423 write_unlock(&em_tree->lock);
4426 btrfs_drop_extent_cache(inode, cur_offset,
4430 free_extent_map(hole_em);
4433 free_extent_map(em);
4435 cur_offset = last_byte;
4436 if (cur_offset >= block_end)
4439 free_extent_map(em);
4440 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
4445 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
4447 struct btrfs_root *root = BTRFS_I(inode)->root;
4448 struct btrfs_trans_handle *trans;
4449 loff_t oldsize = i_size_read(inode);
4450 loff_t newsize = attr->ia_size;
4451 int mask = attr->ia_valid;
4455 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4456 * special case where we need to update the times despite not having
4457 * these flags set. For all other operations the VFS set these flags
4458 * explicitly if it wants a timestamp update.
4460 if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
4461 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
4463 if (newsize > oldsize) {
4464 truncate_pagecache(inode, newsize);
4465 ret = btrfs_cont_expand(inode, oldsize, newsize);
4469 trans = btrfs_start_transaction(root, 1);
4471 return PTR_ERR(trans);
4473 i_size_write(inode, newsize);
4474 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
4475 ret = btrfs_update_inode(trans, root, inode);
4476 btrfs_end_transaction(trans, root);
4480 * We're truncating a file that used to have good data down to
4481 * zero. Make sure it gets into the ordered flush list so that
4482 * any new writes get down to disk quickly.
4485 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4486 &BTRFS_I(inode)->runtime_flags);
4489 * 1 for the orphan item we're going to add
4490 * 1 for the orphan item deletion.
4492 trans = btrfs_start_transaction(root, 2);
4494 return PTR_ERR(trans);
4497 * We need to do this in case we fail at _any_ point during the
4498 * actual truncate. Once we do the truncate_setsize we could
4499 * invalidate pages which forces any outstanding ordered io to
4500 * be instantly completed which will give us extents that need
4501 * to be truncated. If we fail to get an orphan inode down we
4502 * could have left over extents that were never meant to live,
4503 * so we need to garuntee from this point on that everything
4504 * will be consistent.
4506 ret = btrfs_orphan_add(trans, inode);
4507 btrfs_end_transaction(trans, root);
4511 /* we don't support swapfiles, so vmtruncate shouldn't fail */
4512 truncate_setsize(inode, newsize);
4514 /* Disable nonlocked read DIO to avoid the end less truncate */
4515 btrfs_inode_block_unlocked_dio(inode);
4516 inode_dio_wait(inode);
4517 btrfs_inode_resume_unlocked_dio(inode);
4519 ret = btrfs_truncate(inode);
4520 if (ret && inode->i_nlink) {
4524 * failed to truncate, disk_i_size is only adjusted down
4525 * as we remove extents, so it should represent the true
4526 * size of the inode, so reset the in memory size and
4527 * delete our orphan entry.
4529 trans = btrfs_join_transaction(root);
4530 if (IS_ERR(trans)) {
4531 btrfs_orphan_del(NULL, inode);
4534 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
4535 err = btrfs_orphan_del(trans, inode);
4537 btrfs_abort_transaction(trans, root, err);
4538 btrfs_end_transaction(trans, root);
4545 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4547 struct inode *inode = dentry->d_inode;
4548 struct btrfs_root *root = BTRFS_I(inode)->root;
4551 if (btrfs_root_readonly(root))
4554 err = inode_change_ok(inode, attr);
4558 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
4559 err = btrfs_setsize(inode, attr);
4564 if (attr->ia_valid) {
4565 setattr_copy(inode, attr);
4566 inode_inc_iversion(inode);
4567 err = btrfs_dirty_inode(inode);
4569 if (!err && attr->ia_valid & ATTR_MODE)
4570 err = btrfs_acl_chmod(inode);
4577 * While truncating the inode pages during eviction, we get the VFS calling
4578 * btrfs_invalidatepage() against each page of the inode. This is slow because
4579 * the calls to btrfs_invalidatepage() result in a huge amount of calls to
4580 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting
4581 * extent_state structures over and over, wasting lots of time.
4583 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all
4584 * those expensive operations on a per page basis and do only the ordered io
4585 * finishing, while we release here the extent_map and extent_state structures,
4586 * without the excessive merging and splitting.
4588 static void evict_inode_truncate_pages(struct inode *inode)
4590 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4591 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree;
4592 struct rb_node *node;
4594 ASSERT(inode->i_state & I_FREEING);
4595 truncate_inode_pages(&inode->i_data, 0);
4597 write_lock(&map_tree->lock);
4598 while (!RB_EMPTY_ROOT(&map_tree->map)) {
4599 struct extent_map *em;
4601 node = rb_first(&map_tree->map);
4602 em = rb_entry(node, struct extent_map, rb_node);
4603 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
4604 clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
4605 remove_extent_mapping(map_tree, em);
4606 free_extent_map(em);
4608 write_unlock(&map_tree->lock);
4610 spin_lock(&io_tree->lock);
4611 while (!RB_EMPTY_ROOT(&io_tree->state)) {
4612 struct extent_state *state;
4613 struct extent_state *cached_state = NULL;
4615 node = rb_first(&io_tree->state);
4616 state = rb_entry(node, struct extent_state, rb_node);
4617 atomic_inc(&state->refs);
4618 spin_unlock(&io_tree->lock);
4620 lock_extent_bits(io_tree, state->start, state->end,
4622 clear_extent_bit(io_tree, state->start, state->end,
4623 EXTENT_LOCKED | EXTENT_DIRTY |
4624 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
4625 EXTENT_DEFRAG, 1, 1,
4626 &cached_state, GFP_NOFS);
4627 free_extent_state(state);
4629 spin_lock(&io_tree->lock);
4631 spin_unlock(&io_tree->lock);
4634 void btrfs_evict_inode(struct inode *inode)
4636 struct btrfs_trans_handle *trans;
4637 struct btrfs_root *root = BTRFS_I(inode)->root;
4638 struct btrfs_block_rsv *rsv, *global_rsv;
4639 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
4642 trace_btrfs_inode_evict(inode);
4644 evict_inode_truncate_pages(inode);
4646 if (inode->i_nlink &&
4647 ((btrfs_root_refs(&root->root_item) != 0 &&
4648 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
4649 btrfs_is_free_space_inode(inode)))
4652 if (is_bad_inode(inode)) {
4653 btrfs_orphan_del(NULL, inode);
4656 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
4657 btrfs_wait_ordered_range(inode, 0, (u64)-1);
4659 if (root->fs_info->log_root_recovering) {
4660 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
4661 &BTRFS_I(inode)->runtime_flags));
4665 if (inode->i_nlink > 0) {
4666 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
4667 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
4671 ret = btrfs_commit_inode_delayed_inode(inode);
4673 btrfs_orphan_del(NULL, inode);
4677 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
4679 btrfs_orphan_del(NULL, inode);
4682 rsv->size = min_size;
4684 global_rsv = &root->fs_info->global_block_rsv;
4686 btrfs_i_size_write(inode, 0);
4689 * This is a bit simpler than btrfs_truncate since we've already
4690 * reserved our space for our orphan item in the unlink, so we just
4691 * need to reserve some slack space in case we add bytes and update
4692 * inode item when doing the truncate.
4695 ret = btrfs_block_rsv_refill(root, rsv, min_size,
4696 BTRFS_RESERVE_FLUSH_LIMIT);
4699 * Try and steal from the global reserve since we will
4700 * likely not use this space anyway, we want to try as
4701 * hard as possible to get this to work.
4704 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
4707 btrfs_warn(root->fs_info,
4708 "Could not get space for a delete, will truncate on mount %d",
4710 btrfs_orphan_del(NULL, inode);
4711 btrfs_free_block_rsv(root, rsv);
4715 trans = btrfs_join_transaction(root);
4716 if (IS_ERR(trans)) {
4717 btrfs_orphan_del(NULL, inode);
4718 btrfs_free_block_rsv(root, rsv);
4722 trans->block_rsv = rsv;
4724 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
4728 trans->block_rsv = &root->fs_info->trans_block_rsv;
4729 btrfs_end_transaction(trans, root);
4731 btrfs_btree_balance_dirty(root);
4734 btrfs_free_block_rsv(root, rsv);
4737 * Errors here aren't a big deal, it just means we leave orphan items
4738 * in the tree. They will be cleaned up on the next mount.
4741 trans->block_rsv = root->orphan_block_rsv;
4742 btrfs_orphan_del(trans, inode);
4744 btrfs_orphan_del(NULL, inode);
4747 trans->block_rsv = &root->fs_info->trans_block_rsv;
4748 if (!(root == root->fs_info->tree_root ||
4749 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
4750 btrfs_return_ino(root, btrfs_ino(inode));
4752 btrfs_end_transaction(trans, root);
4753 btrfs_btree_balance_dirty(root);
4755 btrfs_remove_delayed_node(inode);
4761 * this returns the key found in the dir entry in the location pointer.
4762 * If no dir entries were found, location->objectid is 0.
4764 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
4765 struct btrfs_key *location)
4767 const char *name = dentry->d_name.name;
4768 int namelen = dentry->d_name.len;
4769 struct btrfs_dir_item *di;
4770 struct btrfs_path *path;
4771 struct btrfs_root *root = BTRFS_I(dir)->root;
4774 path = btrfs_alloc_path();
4778 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
4783 if (IS_ERR_OR_NULL(di))
4786 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
4788 btrfs_free_path(path);
4791 location->objectid = 0;
4796 * when we hit a tree root in a directory, the btrfs part of the inode
4797 * needs to be changed to reflect the root directory of the tree root. This
4798 * is kind of like crossing a mount point.
4800 static int fixup_tree_root_location(struct btrfs_root *root,
4802 struct dentry *dentry,
4803 struct btrfs_key *location,
4804 struct btrfs_root **sub_root)
4806 struct btrfs_path *path;
4807 struct btrfs_root *new_root;
4808 struct btrfs_root_ref *ref;
4809 struct extent_buffer *leaf;
4813 path = btrfs_alloc_path();
4820 ret = btrfs_find_item(root->fs_info->tree_root, path,
4821 BTRFS_I(dir)->root->root_key.objectid,
4822 location->objectid, BTRFS_ROOT_REF_KEY, NULL);
4829 leaf = path->nodes[0];
4830 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
4831 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
4832 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
4835 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
4836 (unsigned long)(ref + 1),
4837 dentry->d_name.len);
4841 btrfs_release_path(path);
4843 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
4844 if (IS_ERR(new_root)) {
4845 err = PTR_ERR(new_root);
4849 *sub_root = new_root;
4850 location->objectid = btrfs_root_dirid(&new_root->root_item);
4851 location->type = BTRFS_INODE_ITEM_KEY;
4852 location->offset = 0;
4855 btrfs_free_path(path);
4859 static void inode_tree_add(struct inode *inode)
4861 struct btrfs_root *root = BTRFS_I(inode)->root;
4862 struct btrfs_inode *entry;
4864 struct rb_node *parent;
4865 struct rb_node *new = &BTRFS_I(inode)->rb_node;
4866 u64 ino = btrfs_ino(inode);
4868 if (inode_unhashed(inode))
4871 spin_lock(&root->inode_lock);
4872 p = &root->inode_tree.rb_node;
4875 entry = rb_entry(parent, struct btrfs_inode, rb_node);
4877 if (ino < btrfs_ino(&entry->vfs_inode))
4878 p = &parent->rb_left;
4879 else if (ino > btrfs_ino(&entry->vfs_inode))
4880 p = &parent->rb_right;
4882 WARN_ON(!(entry->vfs_inode.i_state &
4883 (I_WILL_FREE | I_FREEING)));
4884 rb_replace_node(parent, new, &root->inode_tree);
4885 RB_CLEAR_NODE(parent);
4886 spin_unlock(&root->inode_lock);
4890 rb_link_node(new, parent, p);
4891 rb_insert_color(new, &root->inode_tree);
4892 spin_unlock(&root->inode_lock);
4895 static void inode_tree_del(struct inode *inode)
4897 struct btrfs_root *root = BTRFS_I(inode)->root;
4900 spin_lock(&root->inode_lock);
4901 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
4902 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4903 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
4904 empty = RB_EMPTY_ROOT(&root->inode_tree);
4906 spin_unlock(&root->inode_lock);
4908 if (empty && btrfs_root_refs(&root->root_item) == 0) {
4909 synchronize_srcu(&root->fs_info->subvol_srcu);
4910 spin_lock(&root->inode_lock);
4911 empty = RB_EMPTY_ROOT(&root->inode_tree);
4912 spin_unlock(&root->inode_lock);
4914 btrfs_add_dead_root(root);
4918 void btrfs_invalidate_inodes(struct btrfs_root *root)
4920 struct rb_node *node;
4921 struct rb_node *prev;
4922 struct btrfs_inode *entry;
4923 struct inode *inode;
4926 if (!test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state))
4927 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4929 spin_lock(&root->inode_lock);
4931 node = root->inode_tree.rb_node;
4935 entry = rb_entry(node, struct btrfs_inode, rb_node);
4937 if (objectid < btrfs_ino(&entry->vfs_inode))
4938 node = node->rb_left;
4939 else if (objectid > btrfs_ino(&entry->vfs_inode))
4940 node = node->rb_right;
4946 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4947 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
4951 prev = rb_next(prev);
4955 entry = rb_entry(node, struct btrfs_inode, rb_node);
4956 objectid = btrfs_ino(&entry->vfs_inode) + 1;
4957 inode = igrab(&entry->vfs_inode);
4959 spin_unlock(&root->inode_lock);
4960 if (atomic_read(&inode->i_count) > 1)
4961 d_prune_aliases(inode);
4963 * btrfs_drop_inode will have it removed from
4964 * the inode cache when its usage count
4969 spin_lock(&root->inode_lock);
4973 if (cond_resched_lock(&root->inode_lock))
4976 node = rb_next(node);
4978 spin_unlock(&root->inode_lock);
4981 static int btrfs_init_locked_inode(struct inode *inode, void *p)
4983 struct btrfs_iget_args *args = p;
4984 inode->i_ino = args->location->objectid;
4985 memcpy(&BTRFS_I(inode)->location, args->location,
4986 sizeof(*args->location));
4987 BTRFS_I(inode)->root = args->root;
4991 static int btrfs_find_actor(struct inode *inode, void *opaque)
4993 struct btrfs_iget_args *args = opaque;
4994 return args->location->objectid == BTRFS_I(inode)->location.objectid &&
4995 args->root == BTRFS_I(inode)->root;
4998 static struct inode *btrfs_iget_locked(struct super_block *s,
4999 struct btrfs_key *location,
5000 struct btrfs_root *root)
5002 struct inode *inode;
5003 struct btrfs_iget_args args;
5004 unsigned long hashval = btrfs_inode_hash(location->objectid, root);
5006 args.location = location;
5009 inode = iget5_locked(s, hashval, btrfs_find_actor,
5010 btrfs_init_locked_inode,
5015 /* Get an inode object given its location and corresponding root.
5016 * Returns in *is_new if the inode was read from disk
5018 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
5019 struct btrfs_root *root, int *new)
5021 struct inode *inode;
5023 inode = btrfs_iget_locked(s, location, root);
5025 return ERR_PTR(-ENOMEM);
5027 if (inode->i_state & I_NEW) {
5028 btrfs_read_locked_inode(inode);
5029 if (!is_bad_inode(inode)) {
5030 inode_tree_add(inode);
5031 unlock_new_inode(inode);
5035 unlock_new_inode(inode);
5037 inode = ERR_PTR(-ESTALE);
5044 static struct inode *new_simple_dir(struct super_block *s,
5045 struct btrfs_key *key,
5046 struct btrfs_root *root)
5048 struct inode *inode = new_inode(s);
5051 return ERR_PTR(-ENOMEM);
5053 BTRFS_I(inode)->root = root;
5054 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5055 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5057 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5058 inode->i_op = &btrfs_dir_ro_inode_operations;
5059 inode->i_fop = &simple_dir_operations;
5060 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5061 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5066 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5068 struct inode *inode;
5069 struct btrfs_root *root = BTRFS_I(dir)->root;
5070 struct btrfs_root *sub_root = root;
5071 struct btrfs_key location;
5075 if (dentry->d_name.len > BTRFS_NAME_LEN)
5076 return ERR_PTR(-ENAMETOOLONG);
5078 ret = btrfs_inode_by_name(dir, dentry, &location);
5080 return ERR_PTR(ret);
5082 if (location.objectid == 0)
5083 return ERR_PTR(-ENOENT);
5085 if (location.type == BTRFS_INODE_ITEM_KEY) {
5086 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
5090 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
5092 index = srcu_read_lock(&root->fs_info->subvol_srcu);
5093 ret = fixup_tree_root_location(root, dir, dentry,
5094 &location, &sub_root);
5097 inode = ERR_PTR(ret);
5099 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5101 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
5103 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
5105 if (!IS_ERR(inode) && root != sub_root) {
5106 down_read(&root->fs_info->cleanup_work_sem);
5107 if (!(inode->i_sb->s_flags & MS_RDONLY))
5108 ret = btrfs_orphan_cleanup(sub_root);
5109 up_read(&root->fs_info->cleanup_work_sem);
5112 inode = ERR_PTR(ret);
5119 static int btrfs_dentry_delete(const struct dentry *dentry)
5121 struct btrfs_root *root;
5122 struct inode *inode = dentry->d_inode;
5124 if (!inode && !IS_ROOT(dentry))
5125 inode = dentry->d_parent->d_inode;
5128 root = BTRFS_I(inode)->root;
5129 if (btrfs_root_refs(&root->root_item) == 0)
5132 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5138 static void btrfs_dentry_release(struct dentry *dentry)
5140 if (dentry->d_fsdata)
5141 kfree(dentry->d_fsdata);
5144 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5147 struct inode *inode;
5149 inode = btrfs_lookup_dentry(dir, dentry);
5150 if (IS_ERR(inode)) {
5151 if (PTR_ERR(inode) == -ENOENT)
5154 return ERR_CAST(inode);
5157 return d_materialise_unique(dentry, inode);
5160 unsigned char btrfs_filetype_table[] = {
5161 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5164 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5166 struct inode *inode = file_inode(file);
5167 struct btrfs_root *root = BTRFS_I(inode)->root;
5168 struct btrfs_item *item;
5169 struct btrfs_dir_item *di;
5170 struct btrfs_key key;
5171 struct btrfs_key found_key;
5172 struct btrfs_path *path;
5173 struct list_head ins_list;
5174 struct list_head del_list;
5176 struct extent_buffer *leaf;
5178 unsigned char d_type;
5183 int key_type = BTRFS_DIR_INDEX_KEY;
5187 int is_curr = 0; /* ctx->pos points to the current index? */
5189 /* FIXME, use a real flag for deciding about the key type */
5190 if (root->fs_info->tree_root == root)
5191 key_type = BTRFS_DIR_ITEM_KEY;
5193 if (!dir_emit_dots(file, ctx))
5196 path = btrfs_alloc_path();
5202 if (key_type == BTRFS_DIR_INDEX_KEY) {
5203 INIT_LIST_HEAD(&ins_list);
5204 INIT_LIST_HEAD(&del_list);
5205 btrfs_get_delayed_items(inode, &ins_list, &del_list);
5208 btrfs_set_key_type(&key, key_type);
5209 key.offset = ctx->pos;
5210 key.objectid = btrfs_ino(inode);
5212 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5217 leaf = path->nodes[0];
5218 slot = path->slots[0];
5219 if (slot >= btrfs_header_nritems(leaf)) {
5220 ret = btrfs_next_leaf(root, path);
5228 item = btrfs_item_nr(slot);
5229 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5231 if (found_key.objectid != key.objectid)
5233 if (btrfs_key_type(&found_key) != key_type)
5235 if (found_key.offset < ctx->pos)
5237 if (key_type == BTRFS_DIR_INDEX_KEY &&
5238 btrfs_should_delete_dir_index(&del_list,
5242 ctx->pos = found_key.offset;
5245 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5247 di_total = btrfs_item_size(leaf, item);
5249 while (di_cur < di_total) {
5250 struct btrfs_key location;
5252 if (verify_dir_item(root, leaf, di))
5255 name_len = btrfs_dir_name_len(leaf, di);
5256 if (name_len <= sizeof(tmp_name)) {
5257 name_ptr = tmp_name;
5259 name_ptr = kmalloc(name_len, GFP_NOFS);
5265 read_extent_buffer(leaf, name_ptr,
5266 (unsigned long)(di + 1), name_len);
5268 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
5269 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5272 /* is this a reference to our own snapshot? If so
5275 * In contrast to old kernels, we insert the snapshot's
5276 * dir item and dir index after it has been created, so
5277 * we won't find a reference to our own snapshot. We
5278 * still keep the following code for backward
5281 if (location.type == BTRFS_ROOT_ITEM_KEY &&
5282 location.objectid == root->root_key.objectid) {
5286 over = !dir_emit(ctx, name_ptr, name_len,
5287 location.objectid, d_type);
5290 if (name_ptr != tmp_name)
5295 di_len = btrfs_dir_name_len(leaf, di) +
5296 btrfs_dir_data_len(leaf, di) + sizeof(*di);
5298 di = (struct btrfs_dir_item *)((char *)di + di_len);
5304 if (key_type == BTRFS_DIR_INDEX_KEY) {
5307 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5312 /* Reached end of directory/root. Bump pos past the last item. */
5316 * Stop new entries from being returned after we return the last
5319 * New directory entries are assigned a strictly increasing
5320 * offset. This means that new entries created during readdir
5321 * are *guaranteed* to be seen in the future by that readdir.
5322 * This has broken buggy programs which operate on names as
5323 * they're returned by readdir. Until we re-use freed offsets
5324 * we have this hack to stop new entries from being returned
5325 * under the assumption that they'll never reach this huge
5328 * This is being careful not to overflow 32bit loff_t unless the
5329 * last entry requires it because doing so has broken 32bit apps
5332 if (key_type == BTRFS_DIR_INDEX_KEY) {
5333 if (ctx->pos >= INT_MAX)
5334 ctx->pos = LLONG_MAX;
5341 if (key_type == BTRFS_DIR_INDEX_KEY)
5342 btrfs_put_delayed_items(&ins_list, &del_list);
5343 btrfs_free_path(path);
5347 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
5349 struct btrfs_root *root = BTRFS_I(inode)->root;
5350 struct btrfs_trans_handle *trans;
5352 bool nolock = false;
5354 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5357 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode))
5360 if (wbc->sync_mode == WB_SYNC_ALL) {
5362 trans = btrfs_join_transaction_nolock(root);
5364 trans = btrfs_join_transaction(root);
5366 return PTR_ERR(trans);
5367 ret = btrfs_commit_transaction(trans, root);
5373 * This is somewhat expensive, updating the tree every time the
5374 * inode changes. But, it is most likely to find the inode in cache.
5375 * FIXME, needs more benchmarking...there are no reasons other than performance
5376 * to keep or drop this code.
5378 static int btrfs_dirty_inode(struct inode *inode)
5380 struct btrfs_root *root = BTRFS_I(inode)->root;
5381 struct btrfs_trans_handle *trans;
5384 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5387 trans = btrfs_join_transaction(root);
5389 return PTR_ERR(trans);
5391 ret = btrfs_update_inode(trans, root, inode);
5392 if (ret && ret == -ENOSPC) {
5393 /* whoops, lets try again with the full transaction */
5394 btrfs_end_transaction(trans, root);
5395 trans = btrfs_start_transaction(root, 1);
5397 return PTR_ERR(trans);
5399 ret = btrfs_update_inode(trans, root, inode);
5401 btrfs_end_transaction(trans, root);
5402 if (BTRFS_I(inode)->delayed_node)
5403 btrfs_balance_delayed_items(root);
5409 * This is a copy of file_update_time. We need this so we can return error on
5410 * ENOSPC for updating the inode in the case of file write and mmap writes.
5412 static int btrfs_update_time(struct inode *inode, struct timespec *now,
5415 struct btrfs_root *root = BTRFS_I(inode)->root;
5417 if (btrfs_root_readonly(root))
5420 if (flags & S_VERSION)
5421 inode_inc_iversion(inode);
5422 if (flags & S_CTIME)
5423 inode->i_ctime = *now;
5424 if (flags & S_MTIME)
5425 inode->i_mtime = *now;
5426 if (flags & S_ATIME)
5427 inode->i_atime = *now;
5428 return btrfs_dirty_inode(inode);
5432 * find the highest existing sequence number in a directory
5433 * and then set the in-memory index_cnt variable to reflect
5434 * free sequence numbers
5436 static int btrfs_set_inode_index_count(struct inode *inode)
5438 struct btrfs_root *root = BTRFS_I(inode)->root;
5439 struct btrfs_key key, found_key;
5440 struct btrfs_path *path;
5441 struct extent_buffer *leaf;
5444 key.objectid = btrfs_ino(inode);
5445 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
5446 key.offset = (u64)-1;
5448 path = btrfs_alloc_path();
5452 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5455 /* FIXME: we should be able to handle this */
5461 * MAGIC NUMBER EXPLANATION:
5462 * since we search a directory based on f_pos we have to start at 2
5463 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5464 * else has to start at 2
5466 if (path->slots[0] == 0) {
5467 BTRFS_I(inode)->index_cnt = 2;
5473 leaf = path->nodes[0];
5474 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5476 if (found_key.objectid != btrfs_ino(inode) ||
5477 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
5478 BTRFS_I(inode)->index_cnt = 2;
5482 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
5484 btrfs_free_path(path);
5489 * helper to find a free sequence number in a given directory. This current
5490 * code is very simple, later versions will do smarter things in the btree
5492 int btrfs_set_inode_index(struct inode *dir, u64 *index)
5496 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
5497 ret = btrfs_inode_delayed_dir_index_count(dir);
5499 ret = btrfs_set_inode_index_count(dir);
5505 *index = BTRFS_I(dir)->index_cnt;
5506 BTRFS_I(dir)->index_cnt++;
5511 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5512 struct btrfs_root *root,
5514 const char *name, int name_len,
5515 u64 ref_objectid, u64 objectid,
5516 umode_t mode, u64 *index)
5518 struct inode *inode;
5519 struct btrfs_inode_item *inode_item;
5520 struct btrfs_key *location;
5521 struct btrfs_path *path;
5522 struct btrfs_inode_ref *ref;
5523 struct btrfs_key key[2];
5528 path = btrfs_alloc_path();
5530 return ERR_PTR(-ENOMEM);
5532 inode = new_inode(root->fs_info->sb);
5534 btrfs_free_path(path);
5535 return ERR_PTR(-ENOMEM);
5539 * we have to initialize this early, so we can reclaim the inode
5540 * number if we fail afterwards in this function.
5542 inode->i_ino = objectid;
5545 trace_btrfs_inode_request(dir);
5547 ret = btrfs_set_inode_index(dir, index);
5549 btrfs_free_path(path);
5551 return ERR_PTR(ret);
5555 * index_cnt is ignored for everything but a dir,
5556 * btrfs_get_inode_index_count has an explanation for the magic
5559 BTRFS_I(inode)->index_cnt = 2;
5560 BTRFS_I(inode)->dir_index = *index;
5561 BTRFS_I(inode)->root = root;
5562 BTRFS_I(inode)->generation = trans->transid;
5563 inode->i_generation = BTRFS_I(inode)->generation;
5566 * We could have gotten an inode number from somebody who was fsynced
5567 * and then removed in this same transaction, so let's just set full
5568 * sync since it will be a full sync anyway and this will blow away the
5569 * old info in the log.
5571 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5573 key[0].objectid = objectid;
5574 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
5578 * Start new inodes with an inode_ref. This is slightly more
5579 * efficient for small numbers of hard links since they will
5580 * be packed into one item. Extended refs will kick in if we
5581 * add more hard links than can fit in the ref item.
5583 key[1].objectid = objectid;
5584 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
5585 key[1].offset = ref_objectid;
5587 sizes[0] = sizeof(struct btrfs_inode_item);
5588 sizes[1] = name_len + sizeof(*ref);
5590 path->leave_spinning = 1;
5591 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
5595 inode_init_owner(inode, dir, mode);
5596 inode_set_bytes(inode, 0);
5597 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5598 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
5599 struct btrfs_inode_item);
5600 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
5601 sizeof(*inode_item));
5602 fill_inode_item(trans, path->nodes[0], inode_item, inode);
5604 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
5605 struct btrfs_inode_ref);
5606 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
5607 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
5608 ptr = (unsigned long)(ref + 1);
5609 write_extent_buffer(path->nodes[0], name, ptr, name_len);
5611 btrfs_mark_buffer_dirty(path->nodes[0]);
5612 btrfs_free_path(path);
5614 location = &BTRFS_I(inode)->location;
5615 location->objectid = objectid;
5616 location->offset = 0;
5617 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
5619 btrfs_inherit_iflags(inode, dir);
5621 if (S_ISREG(mode)) {
5622 if (btrfs_test_opt(root, NODATASUM))
5623 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
5624 if (btrfs_test_opt(root, NODATACOW))
5625 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
5626 BTRFS_INODE_NODATASUM;
5629 btrfs_insert_inode_hash(inode);
5630 inode_tree_add(inode);
5632 trace_btrfs_inode_new(inode);
5633 btrfs_set_inode_last_trans(trans, inode);
5635 btrfs_update_root_times(trans, root);
5637 ret = btrfs_inode_inherit_props(trans, inode, dir);
5639 btrfs_err(root->fs_info,
5640 "error inheriting props for ino %llu (root %llu): %d",
5641 btrfs_ino(inode), root->root_key.objectid, ret);
5646 BTRFS_I(dir)->index_cnt--;
5647 btrfs_free_path(path);
5649 return ERR_PTR(ret);
5652 static inline u8 btrfs_inode_type(struct inode *inode)
5654 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
5658 * utility function to add 'inode' into 'parent_inode' with
5659 * a give name and a given sequence number.
5660 * if 'add_backref' is true, also insert a backref from the
5661 * inode to the parent directory.
5663 int btrfs_add_link(struct btrfs_trans_handle *trans,
5664 struct inode *parent_inode, struct inode *inode,
5665 const char *name, int name_len, int add_backref, u64 index)
5668 struct btrfs_key key;
5669 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
5670 u64 ino = btrfs_ino(inode);
5671 u64 parent_ino = btrfs_ino(parent_inode);
5673 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5674 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
5677 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
5681 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5682 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
5683 key.objectid, root->root_key.objectid,
5684 parent_ino, index, name, name_len);
5685 } else if (add_backref) {
5686 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
5690 /* Nothing to clean up yet */
5694 ret = btrfs_insert_dir_item(trans, root, name, name_len,
5696 btrfs_inode_type(inode), index);
5697 if (ret == -EEXIST || ret == -EOVERFLOW)
5700 btrfs_abort_transaction(trans, root, ret);
5704 btrfs_i_size_write(parent_inode, parent_inode->i_size +
5706 inode_inc_iversion(parent_inode);
5707 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
5708 ret = btrfs_update_inode(trans, root, parent_inode);
5710 btrfs_abort_transaction(trans, root, ret);
5714 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5717 err = btrfs_del_root_ref(trans, root->fs_info->tree_root,
5718 key.objectid, root->root_key.objectid,
5719 parent_ino, &local_index, name, name_len);
5721 } else if (add_backref) {
5725 err = btrfs_del_inode_ref(trans, root, name, name_len,
5726 ino, parent_ino, &local_index);
5731 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
5732 struct inode *dir, struct dentry *dentry,
5733 struct inode *inode, int backref, u64 index)
5735 int err = btrfs_add_link(trans, dir, inode,
5736 dentry->d_name.name, dentry->d_name.len,
5743 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
5744 umode_t mode, dev_t rdev)
5746 struct btrfs_trans_handle *trans;
5747 struct btrfs_root *root = BTRFS_I(dir)->root;
5748 struct inode *inode = NULL;
5754 if (!new_valid_dev(rdev))
5758 * 2 for inode item and ref
5760 * 1 for xattr if selinux is on
5762 trans = btrfs_start_transaction(root, 5);
5764 return PTR_ERR(trans);
5766 err = btrfs_find_free_ino(root, &objectid);
5770 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5771 dentry->d_name.len, btrfs_ino(dir), objectid,
5773 if (IS_ERR(inode)) {
5774 err = PTR_ERR(inode);
5778 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5785 * If the active LSM wants to access the inode during
5786 * d_instantiate it needs these. Smack checks to see
5787 * if the filesystem supports xattrs by looking at the
5791 inode->i_op = &btrfs_special_inode_operations;
5792 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5796 init_special_inode(inode, inode->i_mode, rdev);
5797 btrfs_update_inode(trans, root, inode);
5798 d_instantiate(dentry, inode);
5801 btrfs_end_transaction(trans, root);
5802 btrfs_balance_delayed_items(root);
5803 btrfs_btree_balance_dirty(root);
5805 inode_dec_link_count(inode);
5811 static int btrfs_create(struct inode *dir, struct dentry *dentry,
5812 umode_t mode, bool excl)
5814 struct btrfs_trans_handle *trans;
5815 struct btrfs_root *root = BTRFS_I(dir)->root;
5816 struct inode *inode = NULL;
5817 int drop_inode_on_err = 0;
5823 * 2 for inode item and ref
5825 * 1 for xattr if selinux is on
5827 trans = btrfs_start_transaction(root, 5);
5829 return PTR_ERR(trans);
5831 err = btrfs_find_free_ino(root, &objectid);
5835 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5836 dentry->d_name.len, btrfs_ino(dir), objectid,
5838 if (IS_ERR(inode)) {
5839 err = PTR_ERR(inode);
5842 drop_inode_on_err = 1;
5844 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5848 err = btrfs_update_inode(trans, root, inode);
5853 * If the active LSM wants to access the inode during
5854 * d_instantiate it needs these. Smack checks to see
5855 * if the filesystem supports xattrs by looking at the
5858 inode->i_fop = &btrfs_file_operations;
5859 inode->i_op = &btrfs_file_inode_operations;
5861 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5865 inode->i_mapping->a_ops = &btrfs_aops;
5866 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5867 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5868 d_instantiate(dentry, inode);
5871 btrfs_end_transaction(trans, root);
5872 if (err && drop_inode_on_err) {
5873 inode_dec_link_count(inode);
5876 btrfs_balance_delayed_items(root);
5877 btrfs_btree_balance_dirty(root);
5881 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
5882 struct dentry *dentry)
5884 struct btrfs_trans_handle *trans;
5885 struct btrfs_root *root = BTRFS_I(dir)->root;
5886 struct inode *inode = old_dentry->d_inode;
5891 /* do not allow sys_link's with other subvols of the same device */
5892 if (root->objectid != BTRFS_I(inode)->root->objectid)
5895 if (inode->i_nlink >= BTRFS_LINK_MAX)
5898 err = btrfs_set_inode_index(dir, &index);
5903 * 2 items for inode and inode ref
5904 * 2 items for dir items
5905 * 1 item for parent inode
5907 trans = btrfs_start_transaction(root, 5);
5908 if (IS_ERR(trans)) {
5909 err = PTR_ERR(trans);
5913 /* There are several dir indexes for this inode, clear the cache. */
5914 BTRFS_I(inode)->dir_index = 0ULL;
5916 inode_inc_iversion(inode);
5917 inode->i_ctime = CURRENT_TIME;
5919 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
5921 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
5926 struct dentry *parent = dentry->d_parent;
5927 err = btrfs_update_inode(trans, root, inode);
5930 d_instantiate(dentry, inode);
5931 btrfs_log_new_name(trans, inode, NULL, parent);
5934 btrfs_end_transaction(trans, root);
5935 btrfs_balance_delayed_items(root);
5938 inode_dec_link_count(inode);
5941 btrfs_btree_balance_dirty(root);
5945 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
5947 struct inode *inode = NULL;
5948 struct btrfs_trans_handle *trans;
5949 struct btrfs_root *root = BTRFS_I(dir)->root;
5951 int drop_on_err = 0;
5956 * 2 items for inode and ref
5957 * 2 items for dir items
5958 * 1 for xattr if selinux is on
5960 trans = btrfs_start_transaction(root, 5);
5962 return PTR_ERR(trans);
5964 err = btrfs_find_free_ino(root, &objectid);
5968 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5969 dentry->d_name.len, btrfs_ino(dir), objectid,
5970 S_IFDIR | mode, &index);
5971 if (IS_ERR(inode)) {
5972 err = PTR_ERR(inode);
5978 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5982 inode->i_op = &btrfs_dir_inode_operations;
5983 inode->i_fop = &btrfs_dir_file_operations;
5985 btrfs_i_size_write(inode, 0);
5986 err = btrfs_update_inode(trans, root, inode);
5990 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
5991 dentry->d_name.len, 0, index);
5995 d_instantiate(dentry, inode);
5999 btrfs_end_transaction(trans, root);
6002 btrfs_balance_delayed_items(root);
6003 btrfs_btree_balance_dirty(root);
6007 /* helper for btfs_get_extent. Given an existing extent in the tree,
6008 * and an extent that you want to insert, deal with overlap and insert
6009 * the new extent into the tree.
6011 static int merge_extent_mapping(struct extent_map_tree *em_tree,
6012 struct extent_map *existing,
6013 struct extent_map *em,
6014 u64 map_start, u64 map_len)
6018 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
6019 start_diff = map_start - em->start;
6020 em->start = map_start;
6022 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
6023 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
6024 em->block_start += start_diff;
6025 em->block_len -= start_diff;
6027 return add_extent_mapping(em_tree, em, 0);
6030 static noinline int uncompress_inline(struct btrfs_path *path,
6031 struct inode *inode, struct page *page,
6032 size_t pg_offset, u64 extent_offset,
6033 struct btrfs_file_extent_item *item)
6036 struct extent_buffer *leaf = path->nodes[0];
6039 unsigned long inline_size;
6043 WARN_ON(pg_offset != 0);
6044 compress_type = btrfs_file_extent_compression(leaf, item);
6045 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6046 inline_size = btrfs_file_extent_inline_item_len(leaf,
6047 btrfs_item_nr(path->slots[0]));
6048 tmp = kmalloc(inline_size, GFP_NOFS);
6051 ptr = btrfs_file_extent_inline_start(item);
6053 read_extent_buffer(leaf, tmp, ptr, inline_size);
6055 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
6056 ret = btrfs_decompress(compress_type, tmp, page,
6057 extent_offset, inline_size, max_size);
6059 char *kaddr = kmap_atomic(page);
6060 unsigned long copy_size = min_t(u64,
6061 PAGE_CACHE_SIZE - pg_offset,
6062 max_size - extent_offset);
6063 memset(kaddr + pg_offset, 0, copy_size);
6064 kunmap_atomic(kaddr);
6071 * a bit scary, this does extent mapping from logical file offset to the disk.
6072 * the ugly parts come from merging extents from the disk with the in-ram
6073 * representation. This gets more complex because of the data=ordered code,
6074 * where the in-ram extents might be locked pending data=ordered completion.
6076 * This also copies inline extents directly into the page.
6079 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
6080 size_t pg_offset, u64 start, u64 len,
6086 u64 extent_start = 0;
6088 u64 objectid = btrfs_ino(inode);
6090 struct btrfs_path *path = NULL;
6091 struct btrfs_root *root = BTRFS_I(inode)->root;
6092 struct btrfs_file_extent_item *item;
6093 struct extent_buffer *leaf;
6094 struct btrfs_key found_key;
6095 struct extent_map *em = NULL;
6096 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
6097 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6098 struct btrfs_trans_handle *trans = NULL;
6102 read_lock(&em_tree->lock);
6103 em = lookup_extent_mapping(em_tree, start, len);
6105 em->bdev = root->fs_info->fs_devices->latest_bdev;
6106 read_unlock(&em_tree->lock);
6109 if (em->start > start || em->start + em->len <= start)
6110 free_extent_map(em);
6111 else if (em->block_start == EXTENT_MAP_INLINE && page)
6112 free_extent_map(em);
6116 em = alloc_extent_map();
6121 em->bdev = root->fs_info->fs_devices->latest_bdev;
6122 em->start = EXTENT_MAP_HOLE;
6123 em->orig_start = EXTENT_MAP_HOLE;
6125 em->block_len = (u64)-1;
6128 path = btrfs_alloc_path();
6134 * Chances are we'll be called again, so go ahead and do
6140 ret = btrfs_lookup_file_extent(trans, root, path,
6141 objectid, start, trans != NULL);
6148 if (path->slots[0] == 0)
6153 leaf = path->nodes[0];
6154 item = btrfs_item_ptr(leaf, path->slots[0],
6155 struct btrfs_file_extent_item);
6156 /* are we inside the extent that was found? */
6157 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6158 found_type = btrfs_key_type(&found_key);
6159 if (found_key.objectid != objectid ||
6160 found_type != BTRFS_EXTENT_DATA_KEY) {
6162 * If we backup past the first extent we want to move forward
6163 * and see if there is an extent in front of us, otherwise we'll
6164 * say there is a hole for our whole search range which can
6171 found_type = btrfs_file_extent_type(leaf, item);
6172 extent_start = found_key.offset;
6173 compress_type = btrfs_file_extent_compression(leaf, item);
6174 if (found_type == BTRFS_FILE_EXTENT_REG ||
6175 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6176 extent_end = extent_start +
6177 btrfs_file_extent_num_bytes(leaf, item);
6178 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6180 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item);
6181 extent_end = ALIGN(extent_start + size, root->sectorsize);
6184 if (start >= extent_end) {
6186 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6187 ret = btrfs_next_leaf(root, path);
6194 leaf = path->nodes[0];
6196 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6197 if (found_key.objectid != objectid ||
6198 found_key.type != BTRFS_EXTENT_DATA_KEY)
6200 if (start + len <= found_key.offset)
6203 em->orig_start = start;
6204 em->len = found_key.offset - start;
6208 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, item);
6209 if (found_type == BTRFS_FILE_EXTENT_REG ||
6210 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6211 em->start = extent_start;
6212 em->len = extent_end - extent_start;
6213 em->orig_start = extent_start -
6214 btrfs_file_extent_offset(leaf, item);
6215 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
6217 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
6219 em->block_start = EXTENT_MAP_HOLE;
6222 if (compress_type != BTRFS_COMPRESS_NONE) {
6223 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6224 em->compress_type = compress_type;
6225 em->block_start = bytenr;
6226 em->block_len = em->orig_block_len;
6228 bytenr += btrfs_file_extent_offset(leaf, item);
6229 em->block_start = bytenr;
6230 em->block_len = em->len;
6231 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
6232 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6235 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6239 size_t extent_offset;
6242 em->block_start = EXTENT_MAP_INLINE;
6243 if (!page || create) {
6244 em->start = extent_start;
6245 em->len = extent_end - extent_start;
6249 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item);
6250 extent_offset = page_offset(page) + pg_offset - extent_start;
6251 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
6252 size - extent_offset);
6253 em->start = extent_start + extent_offset;
6254 em->len = ALIGN(copy_size, root->sectorsize);
6255 em->orig_block_len = em->len;
6256 em->orig_start = em->start;
6257 if (compress_type) {
6258 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6259 em->compress_type = compress_type;
6261 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6262 if (create == 0 && !PageUptodate(page)) {
6263 if (btrfs_file_extent_compression(leaf, item) !=
6264 BTRFS_COMPRESS_NONE) {
6265 ret = uncompress_inline(path, inode, page,
6267 extent_offset, item);
6268 BUG_ON(ret); /* -ENOMEM */
6271 read_extent_buffer(leaf, map + pg_offset, ptr,
6273 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
6274 memset(map + pg_offset + copy_size, 0,
6275 PAGE_CACHE_SIZE - pg_offset -
6280 flush_dcache_page(page);
6281 } else if (create && PageUptodate(page)) {
6285 free_extent_map(em);
6288 btrfs_release_path(path);
6289 trans = btrfs_join_transaction(root);
6292 return ERR_CAST(trans);
6296 write_extent_buffer(leaf, map + pg_offset, ptr,
6299 btrfs_mark_buffer_dirty(leaf);
6301 set_extent_uptodate(io_tree, em->start,
6302 extent_map_end(em) - 1, NULL, GFP_NOFS);
6305 WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
6309 em->orig_start = start;
6312 em->block_start = EXTENT_MAP_HOLE;
6313 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
6315 btrfs_release_path(path);
6316 if (em->start > start || extent_map_end(em) <= start) {
6317 btrfs_err(root->fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]",
6318 em->start, em->len, start, len);
6324 write_lock(&em_tree->lock);
6325 ret = add_extent_mapping(em_tree, em, 0);
6326 /* it is possible that someone inserted the extent into the tree
6327 * while we had the lock dropped. It is also possible that
6328 * an overlapping map exists in the tree
6330 if (ret == -EEXIST) {
6331 struct extent_map *existing;
6335 existing = lookup_extent_mapping(em_tree, start, len);
6336 if (existing && (existing->start > start ||
6337 existing->start + existing->len <= start)) {
6338 free_extent_map(existing);
6342 existing = lookup_extent_mapping(em_tree, em->start,
6345 err = merge_extent_mapping(em_tree, existing,
6348 free_extent_map(existing);
6350 free_extent_map(em);
6355 free_extent_map(em);
6359 free_extent_map(em);
6364 write_unlock(&em_tree->lock);
6367 trace_btrfs_get_extent(root, em);
6370 btrfs_free_path(path);
6372 ret = btrfs_end_transaction(trans, root);
6377 free_extent_map(em);
6378 return ERR_PTR(err);
6380 BUG_ON(!em); /* Error is always set */
6384 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
6385 size_t pg_offset, u64 start, u64 len,
6388 struct extent_map *em;
6389 struct extent_map *hole_em = NULL;
6390 u64 range_start = start;
6396 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6403 * - a pre-alloc extent,
6404 * there might actually be delalloc bytes behind it.
6406 if (em->block_start != EXTENT_MAP_HOLE &&
6407 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6413 /* check to see if we've wrapped (len == -1 or similar) */
6422 /* ok, we didn't find anything, lets look for delalloc */
6423 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
6424 end, len, EXTENT_DELALLOC, 1);
6425 found_end = range_start + found;
6426 if (found_end < range_start)
6427 found_end = (u64)-1;
6430 * we didn't find anything useful, return
6431 * the original results from get_extent()
6433 if (range_start > end || found_end <= start) {
6439 /* adjust the range_start to make sure it doesn't
6440 * go backwards from the start they passed in
6442 range_start = max(start, range_start);
6443 found = found_end - range_start;
6446 u64 hole_start = start;
6449 em = alloc_extent_map();
6455 * when btrfs_get_extent can't find anything it
6456 * returns one huge hole
6458 * make sure what it found really fits our range, and
6459 * adjust to make sure it is based on the start from
6463 u64 calc_end = extent_map_end(hole_em);
6465 if (calc_end <= start || (hole_em->start > end)) {
6466 free_extent_map(hole_em);
6469 hole_start = max(hole_em->start, start);
6470 hole_len = calc_end - hole_start;
6474 if (hole_em && range_start > hole_start) {
6475 /* our hole starts before our delalloc, so we
6476 * have to return just the parts of the hole
6477 * that go until the delalloc starts
6479 em->len = min(hole_len,
6480 range_start - hole_start);
6481 em->start = hole_start;
6482 em->orig_start = hole_start;
6484 * don't adjust block start at all,
6485 * it is fixed at EXTENT_MAP_HOLE
6487 em->block_start = hole_em->block_start;
6488 em->block_len = hole_len;
6489 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6490 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6492 em->start = range_start;
6494 em->orig_start = range_start;
6495 em->block_start = EXTENT_MAP_DELALLOC;
6496 em->block_len = found;
6498 } else if (hole_em) {
6503 free_extent_map(hole_em);
6505 free_extent_map(em);
6506 return ERR_PTR(err);
6511 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6514 struct btrfs_root *root = BTRFS_I(inode)->root;
6515 struct extent_map *em;
6516 struct btrfs_key ins;
6520 alloc_hint = get_extent_allocation_hint(inode, start, len);
6521 ret = btrfs_reserve_extent(root, len, root->sectorsize, 0,
6522 alloc_hint, &ins, 1);
6524 return ERR_PTR(ret);
6526 em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
6527 ins.offset, ins.offset, ins.offset, 0);
6529 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6533 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
6534 ins.offset, ins.offset, 0);
6536 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6537 free_extent_map(em);
6538 return ERR_PTR(ret);
6545 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6546 * block must be cow'd
6548 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
6549 u64 *orig_start, u64 *orig_block_len,
6552 struct btrfs_trans_handle *trans;
6553 struct btrfs_path *path;
6555 struct extent_buffer *leaf;
6556 struct btrfs_root *root = BTRFS_I(inode)->root;
6557 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6558 struct btrfs_file_extent_item *fi;
6559 struct btrfs_key key;
6566 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
6568 path = btrfs_alloc_path();
6572 ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(inode),
6577 slot = path->slots[0];
6580 /* can't find the item, must cow */
6587 leaf = path->nodes[0];
6588 btrfs_item_key_to_cpu(leaf, &key, slot);
6589 if (key.objectid != btrfs_ino(inode) ||
6590 key.type != BTRFS_EXTENT_DATA_KEY) {
6591 /* not our file or wrong item type, must cow */
6595 if (key.offset > offset) {
6596 /* Wrong offset, must cow */
6600 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6601 found_type = btrfs_file_extent_type(leaf, fi);
6602 if (found_type != BTRFS_FILE_EXTENT_REG &&
6603 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6604 /* not a regular extent, must cow */
6608 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
6611 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6612 if (extent_end <= offset)
6615 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6616 if (disk_bytenr == 0)
6619 if (btrfs_file_extent_compression(leaf, fi) ||
6620 btrfs_file_extent_encryption(leaf, fi) ||
6621 btrfs_file_extent_other_encoding(leaf, fi))
6624 backref_offset = btrfs_file_extent_offset(leaf, fi);
6627 *orig_start = key.offset - backref_offset;
6628 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
6629 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6632 if (btrfs_extent_readonly(root, disk_bytenr))
6635 num_bytes = min(offset + *len, extent_end) - offset;
6636 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6639 range_end = round_up(offset + num_bytes, root->sectorsize) - 1;
6640 ret = test_range_bit(io_tree, offset, range_end,
6641 EXTENT_DELALLOC, 0, NULL);
6648 btrfs_release_path(path);
6651 * look for other files referencing this extent, if we
6652 * find any we must cow
6654 trans = btrfs_join_transaction(root);
6655 if (IS_ERR(trans)) {
6660 ret = btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
6661 key.offset - backref_offset, disk_bytenr);
6662 btrfs_end_transaction(trans, root);
6669 * adjust disk_bytenr and num_bytes to cover just the bytes
6670 * in this extent we are about to write. If there
6671 * are any csums in that range we have to cow in order
6672 * to keep the csums correct
6674 disk_bytenr += backref_offset;
6675 disk_bytenr += offset - key.offset;
6676 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
6679 * all of the above have passed, it is safe to overwrite this extent
6685 btrfs_free_path(path);
6689 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
6690 struct extent_state **cached_state, int writing)
6692 struct btrfs_ordered_extent *ordered;
6696 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6699 * We're concerned with the entire range that we're going to be
6700 * doing DIO to, so we need to make sure theres no ordered
6701 * extents in this range.
6703 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6704 lockend - lockstart + 1);
6707 * We need to make sure there are no buffered pages in this
6708 * range either, we could have raced between the invalidate in
6709 * generic_file_direct_write and locking the extent. The
6710 * invalidate needs to happen so that reads after a write do not
6713 if (!ordered && (!writing ||
6714 !test_range_bit(&BTRFS_I(inode)->io_tree,
6715 lockstart, lockend, EXTENT_UPTODATE, 0,
6719 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6720 cached_state, GFP_NOFS);
6723 btrfs_start_ordered_extent(inode, ordered, 1);
6724 btrfs_put_ordered_extent(ordered);
6726 /* Screw you mmap */
6727 ret = filemap_write_and_wait_range(inode->i_mapping,
6734 * If we found a page that couldn't be invalidated just
6735 * fall back to buffered.
6737 ret = invalidate_inode_pages2_range(inode->i_mapping,
6738 lockstart >> PAGE_CACHE_SHIFT,
6739 lockend >> PAGE_CACHE_SHIFT);
6750 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
6751 u64 len, u64 orig_start,
6752 u64 block_start, u64 block_len,
6753 u64 orig_block_len, u64 ram_bytes,
6756 struct extent_map_tree *em_tree;
6757 struct extent_map *em;
6758 struct btrfs_root *root = BTRFS_I(inode)->root;
6761 em_tree = &BTRFS_I(inode)->extent_tree;
6762 em = alloc_extent_map();
6764 return ERR_PTR(-ENOMEM);
6767 em->orig_start = orig_start;
6768 em->mod_start = start;
6771 em->block_len = block_len;
6772 em->block_start = block_start;
6773 em->bdev = root->fs_info->fs_devices->latest_bdev;
6774 em->orig_block_len = orig_block_len;
6775 em->ram_bytes = ram_bytes;
6776 em->generation = -1;
6777 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6778 if (type == BTRFS_ORDERED_PREALLOC)
6779 set_bit(EXTENT_FLAG_FILLING, &em->flags);
6782 btrfs_drop_extent_cache(inode, em->start,
6783 em->start + em->len - 1, 0);
6784 write_lock(&em_tree->lock);
6785 ret = add_extent_mapping(em_tree, em, 1);
6786 write_unlock(&em_tree->lock);
6787 } while (ret == -EEXIST);
6790 free_extent_map(em);
6791 return ERR_PTR(ret);
6798 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
6799 struct buffer_head *bh_result, int create)
6801 struct extent_map *em;
6802 struct btrfs_root *root = BTRFS_I(inode)->root;
6803 struct extent_state *cached_state = NULL;
6804 u64 start = iblock << inode->i_blkbits;
6805 u64 lockstart, lockend;
6806 u64 len = bh_result->b_size;
6807 int unlock_bits = EXTENT_LOCKED;
6811 unlock_bits |= EXTENT_DELALLOC | EXTENT_DIRTY;
6813 len = min_t(u64, len, root->sectorsize);
6816 lockend = start + len - 1;
6819 * If this errors out it's because we couldn't invalidate pagecache for
6820 * this range and we need to fallback to buffered.
6822 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create))
6825 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
6832 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
6833 * io. INLINE is special, and we could probably kludge it in here, but
6834 * it's still buffered so for safety lets just fall back to the generic
6837 * For COMPRESSED we _have_ to read the entire extent in so we can
6838 * decompress it, so there will be buffering required no matter what we
6839 * do, so go ahead and fallback to buffered.
6841 * We return -ENOTBLK because thats what makes DIO go ahead and go back
6842 * to buffered IO. Don't blame me, this is the price we pay for using
6845 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
6846 em->block_start == EXTENT_MAP_INLINE) {
6847 free_extent_map(em);
6852 /* Just a good old fashioned hole, return */
6853 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
6854 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
6855 free_extent_map(em);
6860 * We don't allocate a new extent in the following cases
6862 * 1) The inode is marked as NODATACOW. In this case we'll just use the
6864 * 2) The extent is marked as PREALLOC. We're good to go here and can
6865 * just use the extent.
6869 len = min(len, em->len - (start - em->start));
6870 lockstart = start + len;
6874 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
6875 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
6876 em->block_start != EXTENT_MAP_HOLE)) {
6879 u64 block_start, orig_start, orig_block_len, ram_bytes;
6881 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6882 type = BTRFS_ORDERED_PREALLOC;
6884 type = BTRFS_ORDERED_NOCOW;
6885 len = min(len, em->len - (start - em->start));
6886 block_start = em->block_start + (start - em->start);
6888 if (can_nocow_extent(inode, start, &len, &orig_start,
6889 &orig_block_len, &ram_bytes) == 1) {
6890 if (type == BTRFS_ORDERED_PREALLOC) {
6891 free_extent_map(em);
6892 em = create_pinned_em(inode, start, len,
6901 ret = btrfs_add_ordered_extent_dio(inode, start,
6902 block_start, len, len, type);
6904 free_extent_map(em);
6912 * this will cow the extent, reset the len in case we changed
6915 len = bh_result->b_size;
6916 free_extent_map(em);
6917 em = btrfs_new_extent_direct(inode, start, len);
6922 len = min(len, em->len - (start - em->start));
6924 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
6926 bh_result->b_size = len;
6927 bh_result->b_bdev = em->bdev;
6928 set_buffer_mapped(bh_result);
6930 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6931 set_buffer_new(bh_result);
6934 * Need to update the i_size under the extent lock so buffered
6935 * readers will get the updated i_size when we unlock.
6937 if (start + len > i_size_read(inode))
6938 i_size_write(inode, start + len);
6940 spin_lock(&BTRFS_I(inode)->lock);
6941 BTRFS_I(inode)->outstanding_extents++;
6942 spin_unlock(&BTRFS_I(inode)->lock);
6944 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6945 lockstart + len - 1, EXTENT_DELALLOC, NULL,
6946 &cached_state, GFP_NOFS);
6951 * In the case of write we need to clear and unlock the entire range,
6952 * in the case of read we need to unlock only the end area that we
6953 * aren't using if there is any left over space.
6955 if (lockstart < lockend) {
6956 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6957 lockend, unlock_bits, 1, 0,
6958 &cached_state, GFP_NOFS);
6960 free_extent_state(cached_state);
6963 free_extent_map(em);
6968 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6969 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
6973 static void btrfs_endio_direct_read(struct bio *bio, int err)
6975 struct btrfs_dio_private *dip = bio->bi_private;
6976 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
6977 struct bio_vec *bvec = bio->bi_io_vec;
6978 struct inode *inode = dip->inode;
6979 struct btrfs_root *root = BTRFS_I(inode)->root;
6980 struct bio *dio_bio;
6981 u32 *csums = (u32 *)dip->csum;
6985 start = dip->logical_offset;
6987 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
6988 struct page *page = bvec->bv_page;
6991 unsigned long flags;
6993 local_irq_save(flags);
6994 kaddr = kmap_atomic(page);
6995 csum = btrfs_csum_data(kaddr + bvec->bv_offset,
6996 csum, bvec->bv_len);
6997 btrfs_csum_final(csum, (char *)&csum);
6998 kunmap_atomic(kaddr);
6999 local_irq_restore(flags);
7001 flush_dcache_page(bvec->bv_page);
7002 if (csum != csums[index]) {
7003 btrfs_err(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
7004 btrfs_ino(inode), start, csum,
7010 start += bvec->bv_len;
7013 } while (bvec <= bvec_end);
7015 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
7016 dip->logical_offset + dip->bytes - 1);
7017 dio_bio = dip->dio_bio;
7021 /* If we had a csum failure make sure to clear the uptodate flag */
7023 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
7024 dio_end_io(dio_bio, err);
7028 static void btrfs_endio_direct_write(struct bio *bio, int err)
7030 struct btrfs_dio_private *dip = bio->bi_private;
7031 struct inode *inode = dip->inode;
7032 struct btrfs_root *root = BTRFS_I(inode)->root;
7033 struct btrfs_ordered_extent *ordered = NULL;
7034 u64 ordered_offset = dip->logical_offset;
7035 u64 ordered_bytes = dip->bytes;
7036 struct bio *dio_bio;
7042 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
7044 ordered_bytes, !err);
7048 btrfs_init_work(&ordered->work, finish_ordered_fn, NULL, NULL);
7049 btrfs_queue_work(root->fs_info->endio_write_workers,
7053 * our bio might span multiple ordered extents. If we haven't
7054 * completed the accounting for the whole dio, go back and try again
7056 if (ordered_offset < dip->logical_offset + dip->bytes) {
7057 ordered_bytes = dip->logical_offset + dip->bytes -
7063 dio_bio = dip->dio_bio;
7067 /* If we had an error make sure to clear the uptodate flag */
7069 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
7070 dio_end_io(dio_bio, err);
7074 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
7075 struct bio *bio, int mirror_num,
7076 unsigned long bio_flags, u64 offset)
7079 struct btrfs_root *root = BTRFS_I(inode)->root;
7080 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
7081 BUG_ON(ret); /* -ENOMEM */
7085 static void btrfs_end_dio_bio(struct bio *bio, int err)
7087 struct btrfs_dio_private *dip = bio->bi_private;
7090 btrfs_err(BTRFS_I(dip->inode)->root->fs_info,
7091 "direct IO failed ino %llu rw %lu sector %#Lx len %u err no %d",
7092 btrfs_ino(dip->inode), bio->bi_rw,
7093 (unsigned long long)bio->bi_sector, bio->bi_size, err);
7097 * before atomic variable goto zero, we must make sure
7098 * dip->errors is perceived to be set.
7100 smp_mb__before_atomic_dec();
7103 /* if there are more bios still pending for this dio, just exit */
7104 if (!atomic_dec_and_test(&dip->pending_bios))
7108 bio_io_error(dip->orig_bio);
7110 set_bit(BIO_UPTODATE, &dip->dio_bio->bi_flags);
7111 bio_endio(dip->orig_bio, 0);
7117 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
7118 u64 first_sector, gfp_t gfp_flags)
7120 int nr_vecs = bio_get_nr_vecs(bdev);
7121 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
7124 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
7125 int rw, u64 file_offset, int skip_sum,
7128 struct btrfs_dio_private *dip = bio->bi_private;
7129 int write = rw & REQ_WRITE;
7130 struct btrfs_root *root = BTRFS_I(inode)->root;
7134 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
7139 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
7147 if (write && async_submit) {
7148 ret = btrfs_wq_submit_bio(root->fs_info,
7149 inode, rw, bio, 0, 0,
7151 __btrfs_submit_bio_start_direct_io,
7152 __btrfs_submit_bio_done);
7156 * If we aren't doing async submit, calculate the csum of the
7159 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
7162 } else if (!skip_sum) {
7163 ret = btrfs_lookup_bio_sums_dio(root, inode, dip, bio,
7170 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
7176 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
7179 struct inode *inode = dip->inode;
7180 struct btrfs_root *root = BTRFS_I(inode)->root;
7182 struct bio *orig_bio = dip->orig_bio;
7183 struct bio_vec *bvec = orig_bio->bi_io_vec;
7184 u64 start_sector = orig_bio->bi_sector;
7185 u64 file_offset = dip->logical_offset;
7190 int async_submit = 0;
7192 map_length = orig_bio->bi_size;
7193 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9,
7194 &map_length, NULL, 0);
7200 if (map_length >= orig_bio->bi_size) {
7205 /* async crcs make it difficult to collect full stripe writes. */
7206 if (btrfs_get_alloc_profile(root, 1) &
7207 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
7212 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
7215 bio->bi_private = dip;
7216 bio->bi_end_io = btrfs_end_dio_bio;
7217 atomic_inc(&dip->pending_bios);
7219 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
7220 if (unlikely(map_length < submit_len + bvec->bv_len ||
7221 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
7222 bvec->bv_offset) < bvec->bv_len)) {
7224 * inc the count before we submit the bio so
7225 * we know the end IO handler won't happen before
7226 * we inc the count. Otherwise, the dip might get freed
7227 * before we're done setting it up
7229 atomic_inc(&dip->pending_bios);
7230 ret = __btrfs_submit_dio_bio(bio, inode, rw,
7231 file_offset, skip_sum,
7235 atomic_dec(&dip->pending_bios);
7239 start_sector += submit_len >> 9;
7240 file_offset += submit_len;
7245 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
7246 start_sector, GFP_NOFS);
7249 bio->bi_private = dip;
7250 bio->bi_end_io = btrfs_end_dio_bio;
7252 map_length = orig_bio->bi_size;
7253 ret = btrfs_map_block(root->fs_info, rw,
7255 &map_length, NULL, 0);
7261 submit_len += bvec->bv_len;
7268 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
7277 * before atomic variable goto zero, we must
7278 * make sure dip->errors is perceived to be set.
7280 smp_mb__before_atomic_dec();
7281 if (atomic_dec_and_test(&dip->pending_bios))
7282 bio_io_error(dip->orig_bio);
7284 /* bio_end_io() will handle error, so we needn't return it */
7288 static void btrfs_submit_direct(int rw, struct bio *dio_bio,
7289 struct inode *inode, loff_t file_offset)
7291 struct btrfs_root *root = BTRFS_I(inode)->root;
7292 struct btrfs_dio_private *dip;
7296 int write = rw & REQ_WRITE;
7300 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
7302 io_bio = btrfs_bio_clone(dio_bio, GFP_NOFS);
7308 if (!skip_sum && !write) {
7309 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
7310 sum_len = dio_bio->bi_size >> inode->i_sb->s_blocksize_bits;
7311 sum_len *= csum_size;
7316 dip = kmalloc(sizeof(*dip) + sum_len, GFP_NOFS);
7322 dip->private = dio_bio->bi_private;
7324 dip->logical_offset = file_offset;
7325 dip->bytes = dio_bio->bi_size;
7326 dip->disk_bytenr = (u64)dio_bio->bi_sector << 9;
7327 io_bio->bi_private = dip;
7329 dip->orig_bio = io_bio;
7330 dip->dio_bio = dio_bio;
7331 atomic_set(&dip->pending_bios, 0);
7334 io_bio->bi_end_io = btrfs_endio_direct_write;
7336 io_bio->bi_end_io = btrfs_endio_direct_read;
7338 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
7347 * If this is a write, we need to clean up the reserved space and kill
7348 * the ordered extent.
7351 struct btrfs_ordered_extent *ordered;
7352 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
7353 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
7354 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
7355 btrfs_free_reserved_extent(root, ordered->start,
7357 btrfs_put_ordered_extent(ordered);
7358 btrfs_put_ordered_extent(ordered);
7360 bio_endio(dio_bio, ret);
7363 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
7364 const struct iovec *iov, loff_t offset,
7365 unsigned long nr_segs)
7371 unsigned blocksize_mask = root->sectorsize - 1;
7372 ssize_t retval = -EINVAL;
7373 loff_t end = offset;
7375 if (offset & blocksize_mask)
7378 /* Check the memory alignment. Blocks cannot straddle pages */
7379 for (seg = 0; seg < nr_segs; seg++) {
7380 addr = (unsigned long)iov[seg].iov_base;
7381 size = iov[seg].iov_len;
7383 if ((addr & blocksize_mask) || (size & blocksize_mask))
7386 /* If this is a write we don't need to check anymore */
7391 * Check to make sure we don't have duplicate iov_base's in this
7392 * iovec, if so return EINVAL, otherwise we'll get csum errors
7393 * when reading back.
7395 for (i = seg + 1; i < nr_segs; i++) {
7396 if (iov[seg].iov_base == iov[i].iov_base)
7405 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
7406 const struct iovec *iov, loff_t offset,
7407 unsigned long nr_segs)
7409 struct file *file = iocb->ki_filp;
7410 struct inode *inode = file->f_mapping->host;
7414 bool relock = false;
7417 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
7421 atomic_inc(&inode->i_dio_count);
7422 smp_mb__after_atomic_inc();
7425 * The generic stuff only does filemap_write_and_wait_range, which isn't
7426 * enough if we've written compressed pages to this area, so we need to
7427 * call btrfs_wait_ordered_range to make absolutely sure that any
7428 * outstanding dirty pages are on disk.
7430 count = iov_length(iov, nr_segs);
7431 ret = btrfs_wait_ordered_range(inode, offset, count);
7437 * If the write DIO is beyond the EOF, we need update
7438 * the isize, but it is protected by i_mutex. So we can
7439 * not unlock the i_mutex at this case.
7441 if (offset + count <= inode->i_size) {
7442 mutex_unlock(&inode->i_mutex);
7445 ret = btrfs_delalloc_reserve_space(inode, count);
7448 } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7449 &BTRFS_I(inode)->runtime_flags))) {
7450 inode_dio_done(inode);
7451 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7455 ret = __blockdev_direct_IO(rw, iocb, inode,
7456 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
7457 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
7458 btrfs_submit_direct, flags);
7460 if (ret < 0 && ret != -EIOCBQUEUED)
7461 btrfs_delalloc_release_space(inode, count);
7462 else if (ret >= 0 && (size_t)ret < count)
7463 btrfs_delalloc_release_space(inode,
7464 count - (size_t)ret);
7466 btrfs_delalloc_release_metadata(inode, 0);
7470 inode_dio_done(inode);
7472 mutex_lock(&inode->i_mutex);
7477 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7479 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7480 __u64 start, __u64 len)
7484 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7488 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
7491 int btrfs_readpage(struct file *file, struct page *page)
7493 struct extent_io_tree *tree;
7494 tree = &BTRFS_I(page->mapping->host)->io_tree;
7495 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
7498 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
7500 struct extent_io_tree *tree;
7503 if (current->flags & PF_MEMALLOC) {
7504 redirty_page_for_writepage(wbc, page);
7508 tree = &BTRFS_I(page->mapping->host)->io_tree;
7509 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
7512 static int btrfs_writepages(struct address_space *mapping,
7513 struct writeback_control *wbc)
7515 struct extent_io_tree *tree;
7517 tree = &BTRFS_I(mapping->host)->io_tree;
7518 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
7522 btrfs_readpages(struct file *file, struct address_space *mapping,
7523 struct list_head *pages, unsigned nr_pages)
7525 struct extent_io_tree *tree;
7526 tree = &BTRFS_I(mapping->host)->io_tree;
7527 return extent_readpages(tree, mapping, pages, nr_pages,
7530 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7532 struct extent_io_tree *tree;
7533 struct extent_map_tree *map;
7536 tree = &BTRFS_I(page->mapping->host)->io_tree;
7537 map = &BTRFS_I(page->mapping->host)->extent_tree;
7538 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
7540 ClearPagePrivate(page);
7541 set_page_private(page, 0);
7542 page_cache_release(page);
7547 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7549 if (PageWriteback(page) || PageDirty(page))
7551 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
7554 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
7555 unsigned int length)
7557 struct inode *inode = page->mapping->host;
7558 struct extent_io_tree *tree;
7559 struct btrfs_ordered_extent *ordered;
7560 struct extent_state *cached_state = NULL;
7561 u64 page_start = page_offset(page);
7562 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
7563 int inode_evicting = inode->i_state & I_FREEING;
7566 * we have the page locked, so new writeback can't start,
7567 * and the dirty bit won't be cleared while we are here.
7569 * Wait for IO on this page so that we can safely clear
7570 * the PagePrivate2 bit and do ordered accounting
7572 wait_on_page_writeback(page);
7574 tree = &BTRFS_I(inode)->io_tree;
7576 btrfs_releasepage(page, GFP_NOFS);
7580 if (!inode_evicting)
7581 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7582 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7585 * IO on this page will never be started, so we need
7586 * to account for any ordered extents now
7588 if (!inode_evicting)
7589 clear_extent_bit(tree, page_start, page_end,
7590 EXTENT_DIRTY | EXTENT_DELALLOC |
7591 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
7592 EXTENT_DEFRAG, 1, 0, &cached_state,
7595 * whoever cleared the private bit is responsible
7596 * for the finish_ordered_io
7598 if (TestClearPagePrivate2(page)) {
7599 struct btrfs_ordered_inode_tree *tree;
7602 tree = &BTRFS_I(inode)->ordered_tree;
7604 spin_lock_irq(&tree->lock);
7605 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
7606 new_len = page_start - ordered->file_offset;
7607 if (new_len < ordered->truncated_len)
7608 ordered->truncated_len = new_len;
7609 spin_unlock_irq(&tree->lock);
7611 if (btrfs_dec_test_ordered_pending(inode, &ordered,
7613 PAGE_CACHE_SIZE, 1))
7614 btrfs_finish_ordered_io(ordered);
7616 btrfs_put_ordered_extent(ordered);
7617 if (!inode_evicting) {
7618 cached_state = NULL;
7619 lock_extent_bits(tree, page_start, page_end, 0,
7624 if (!inode_evicting) {
7625 clear_extent_bit(tree, page_start, page_end,
7626 EXTENT_LOCKED | EXTENT_DIRTY |
7627 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
7628 EXTENT_DEFRAG, 1, 1,
7629 &cached_state, GFP_NOFS);
7631 __btrfs_releasepage(page, GFP_NOFS);
7634 ClearPageChecked(page);
7635 if (PagePrivate(page)) {
7636 ClearPagePrivate(page);
7637 set_page_private(page, 0);
7638 page_cache_release(page);
7643 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
7644 * called from a page fault handler when a page is first dirtied. Hence we must
7645 * be careful to check for EOF conditions here. We set the page up correctly
7646 * for a written page which means we get ENOSPC checking when writing into
7647 * holes and correct delalloc and unwritten extent mapping on filesystems that
7648 * support these features.
7650 * We are not allowed to take the i_mutex here so we have to play games to
7651 * protect against truncate races as the page could now be beyond EOF. Because
7652 * vmtruncate() writes the inode size before removing pages, once we have the
7653 * page lock we can determine safely if the page is beyond EOF. If it is not
7654 * beyond EOF, then the page is guaranteed safe against truncation until we
7657 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
7659 struct page *page = vmf->page;
7660 struct inode *inode = file_inode(vma->vm_file);
7661 struct btrfs_root *root = BTRFS_I(inode)->root;
7662 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7663 struct btrfs_ordered_extent *ordered;
7664 struct extent_state *cached_state = NULL;
7666 unsigned long zero_start;
7673 sb_start_pagefault(inode->i_sb);
7674 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
7676 ret = file_update_time(vma->vm_file);
7682 else /* -ENOSPC, -EIO, etc */
7683 ret = VM_FAULT_SIGBUS;
7689 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
7692 size = i_size_read(inode);
7693 page_start = page_offset(page);
7694 page_end = page_start + PAGE_CACHE_SIZE - 1;
7696 if ((page->mapping != inode->i_mapping) ||
7697 (page_start >= size)) {
7698 /* page got truncated out from underneath us */
7701 wait_on_page_writeback(page);
7703 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
7704 set_page_extent_mapped(page);
7707 * we can't set the delalloc bits if there are pending ordered
7708 * extents. Drop our locks and wait for them to finish
7710 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7712 unlock_extent_cached(io_tree, page_start, page_end,
7713 &cached_state, GFP_NOFS);
7715 btrfs_start_ordered_extent(inode, ordered, 1);
7716 btrfs_put_ordered_extent(ordered);
7721 * XXX - page_mkwrite gets called every time the page is dirtied, even
7722 * if it was already dirty, so for space accounting reasons we need to
7723 * clear any delalloc bits for the range we are fixing to save. There
7724 * is probably a better way to do this, but for now keep consistent with
7725 * prepare_pages in the normal write path.
7727 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
7728 EXTENT_DIRTY | EXTENT_DELALLOC |
7729 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
7730 0, 0, &cached_state, GFP_NOFS);
7732 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
7735 unlock_extent_cached(io_tree, page_start, page_end,
7736 &cached_state, GFP_NOFS);
7737 ret = VM_FAULT_SIGBUS;
7742 /* page is wholly or partially inside EOF */
7743 if (page_start + PAGE_CACHE_SIZE > size)
7744 zero_start = size & ~PAGE_CACHE_MASK;
7746 zero_start = PAGE_CACHE_SIZE;
7748 if (zero_start != PAGE_CACHE_SIZE) {
7750 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
7751 flush_dcache_page(page);
7754 ClearPageChecked(page);
7755 set_page_dirty(page);
7756 SetPageUptodate(page);
7758 BTRFS_I(inode)->last_trans = root->fs_info->generation;
7759 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
7760 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
7762 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
7766 sb_end_pagefault(inode->i_sb);
7767 return VM_FAULT_LOCKED;
7771 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
7773 sb_end_pagefault(inode->i_sb);
7777 static int btrfs_truncate(struct inode *inode)
7779 struct btrfs_root *root = BTRFS_I(inode)->root;
7780 struct btrfs_block_rsv *rsv;
7783 struct btrfs_trans_handle *trans;
7784 u64 mask = root->sectorsize - 1;
7785 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
7787 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
7793 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
7794 * 3 things going on here
7796 * 1) We need to reserve space for our orphan item and the space to
7797 * delete our orphan item. Lord knows we don't want to have a dangling
7798 * orphan item because we didn't reserve space to remove it.
7800 * 2) We need to reserve space to update our inode.
7802 * 3) We need to have something to cache all the space that is going to
7803 * be free'd up by the truncate operation, but also have some slack
7804 * space reserved in case it uses space during the truncate (thank you
7805 * very much snapshotting).
7807 * And we need these to all be seperate. The fact is we can use alot of
7808 * space doing the truncate, and we have no earthly idea how much space
7809 * we will use, so we need the truncate reservation to be seperate so it
7810 * doesn't end up using space reserved for updating the inode or
7811 * removing the orphan item. We also need to be able to stop the
7812 * transaction and start a new one, which means we need to be able to
7813 * update the inode several times, and we have no idea of knowing how
7814 * many times that will be, so we can't just reserve 1 item for the
7815 * entirety of the opration, so that has to be done seperately as well.
7816 * Then there is the orphan item, which does indeed need to be held on
7817 * to for the whole operation, and we need nobody to touch this reserved
7818 * space except the orphan code.
7820 * So that leaves us with
7822 * 1) root->orphan_block_rsv - for the orphan deletion.
7823 * 2) rsv - for the truncate reservation, which we will steal from the
7824 * transaction reservation.
7825 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
7826 * updating the inode.
7828 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
7831 rsv->size = min_size;
7835 * 1 for the truncate slack space
7836 * 1 for updating the inode.
7838 trans = btrfs_start_transaction(root, 2);
7839 if (IS_ERR(trans)) {
7840 err = PTR_ERR(trans);
7844 /* Migrate the slack space for the truncate to our reserve */
7845 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
7850 * setattr is responsible for setting the ordered_data_close flag,
7851 * but that is only tested during the last file release. That
7852 * could happen well after the next commit, leaving a great big
7853 * window where new writes may get lost if someone chooses to write
7854 * to this file after truncating to zero
7856 * The inode doesn't have any dirty data here, and so if we commit
7857 * this is a noop. If someone immediately starts writing to the inode
7858 * it is very likely we'll catch some of their writes in this
7859 * transaction, and the commit will find this file on the ordered
7860 * data list with good things to send down.
7862 * This is a best effort solution, there is still a window where
7863 * using truncate to replace the contents of the file will
7864 * end up with a zero length file after a crash.
7866 if (inode->i_size == 0 && test_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
7867 &BTRFS_I(inode)->runtime_flags))
7868 btrfs_add_ordered_operation(trans, root, inode);
7871 * So if we truncate and then write and fsync we normally would just
7872 * write the extents that changed, which is a problem if we need to
7873 * first truncate that entire inode. So set this flag so we write out
7874 * all of the extents in the inode to the sync log so we're completely
7877 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
7878 trans->block_rsv = rsv;
7881 ret = btrfs_truncate_inode_items(trans, root, inode,
7883 BTRFS_EXTENT_DATA_KEY);
7884 if (ret != -ENOSPC) {
7889 trans->block_rsv = &root->fs_info->trans_block_rsv;
7890 ret = btrfs_update_inode(trans, root, inode);
7896 btrfs_end_transaction(trans, root);
7897 btrfs_btree_balance_dirty(root);
7899 trans = btrfs_start_transaction(root, 2);
7900 if (IS_ERR(trans)) {
7901 ret = err = PTR_ERR(trans);
7906 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
7908 BUG_ON(ret); /* shouldn't happen */
7909 trans->block_rsv = rsv;
7912 if (ret == 0 && inode->i_nlink > 0) {
7913 trans->block_rsv = root->orphan_block_rsv;
7914 ret = btrfs_orphan_del(trans, inode);
7920 trans->block_rsv = &root->fs_info->trans_block_rsv;
7921 ret = btrfs_update_inode(trans, root, inode);
7925 ret = btrfs_end_transaction(trans, root);
7926 btrfs_btree_balance_dirty(root);
7930 btrfs_free_block_rsv(root, rsv);
7939 * create a new subvolume directory/inode (helper for the ioctl).
7941 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
7942 struct btrfs_root *new_root,
7943 struct btrfs_root *parent_root,
7946 struct inode *inode;
7950 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
7951 new_dirid, new_dirid,
7952 S_IFDIR | (~current_umask() & S_IRWXUGO),
7955 return PTR_ERR(inode);
7956 inode->i_op = &btrfs_dir_inode_operations;
7957 inode->i_fop = &btrfs_dir_file_operations;
7959 set_nlink(inode, 1);
7960 btrfs_i_size_write(inode, 0);
7962 err = btrfs_subvol_inherit_props(trans, new_root, parent_root);
7964 btrfs_err(new_root->fs_info,
7965 "error inheriting subvolume %llu properties: %d\n",
7966 new_root->root_key.objectid, err);
7968 err = btrfs_update_inode(trans, new_root, inode);
7974 struct inode *btrfs_alloc_inode(struct super_block *sb)
7976 struct btrfs_inode *ei;
7977 struct inode *inode;
7979 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
7986 ei->last_sub_trans = 0;
7987 ei->logged_trans = 0;
7988 ei->delalloc_bytes = 0;
7989 ei->disk_i_size = 0;
7992 ei->index_cnt = (u64)-1;
7994 ei->last_unlink_trans = 0;
7995 ei->last_log_commit = 0;
7997 spin_lock_init(&ei->lock);
7998 ei->outstanding_extents = 0;
7999 ei->reserved_extents = 0;
8001 ei->runtime_flags = 0;
8002 ei->force_compress = BTRFS_COMPRESS_NONE;
8004 ei->delayed_node = NULL;
8006 inode = &ei->vfs_inode;
8007 extent_map_tree_init(&ei->extent_tree);
8008 extent_io_tree_init(&ei->io_tree, &inode->i_data);
8009 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
8010 ei->io_tree.track_uptodate = 1;
8011 ei->io_failure_tree.track_uptodate = 1;
8012 atomic_set(&ei->sync_writers, 0);
8013 mutex_init(&ei->log_mutex);
8014 mutex_init(&ei->delalloc_mutex);
8015 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
8016 INIT_LIST_HEAD(&ei->delalloc_inodes);
8017 INIT_LIST_HEAD(&ei->ordered_operations);
8018 RB_CLEAR_NODE(&ei->rb_node);
8023 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8024 void btrfs_test_destroy_inode(struct inode *inode)
8026 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
8027 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8031 static void btrfs_i_callback(struct rcu_head *head)
8033 struct inode *inode = container_of(head, struct inode, i_rcu);
8034 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8037 void btrfs_destroy_inode(struct inode *inode)
8039 struct btrfs_ordered_extent *ordered;
8040 struct btrfs_root *root = BTRFS_I(inode)->root;
8042 WARN_ON(!hlist_empty(&inode->i_dentry));
8043 WARN_ON(inode->i_data.nrpages);
8044 WARN_ON(BTRFS_I(inode)->outstanding_extents);
8045 WARN_ON(BTRFS_I(inode)->reserved_extents);
8046 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
8047 WARN_ON(BTRFS_I(inode)->csum_bytes);
8050 * This can happen where we create an inode, but somebody else also
8051 * created the same inode and we need to destroy the one we already
8058 * Make sure we're properly removed from the ordered operation
8062 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
8063 spin_lock(&root->fs_info->ordered_root_lock);
8064 list_del_init(&BTRFS_I(inode)->ordered_operations);
8065 spin_unlock(&root->fs_info->ordered_root_lock);
8068 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
8069 &BTRFS_I(inode)->runtime_flags)) {
8070 btrfs_info(root->fs_info, "inode %llu still on the orphan list",
8072 atomic_dec(&root->orphan_inodes);
8076 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
8080 btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup",
8081 ordered->file_offset, ordered->len);
8082 btrfs_remove_ordered_extent(inode, ordered);
8083 btrfs_put_ordered_extent(ordered);
8084 btrfs_put_ordered_extent(ordered);
8087 inode_tree_del(inode);
8088 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
8090 call_rcu(&inode->i_rcu, btrfs_i_callback);
8093 int btrfs_drop_inode(struct inode *inode)
8095 struct btrfs_root *root = BTRFS_I(inode)->root;
8100 /* the snap/subvol tree is on deleting */
8101 if (btrfs_root_refs(&root->root_item) == 0)
8104 return generic_drop_inode(inode);
8107 static void init_once(void *foo)
8109 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
8111 inode_init_once(&ei->vfs_inode);
8114 void btrfs_destroy_cachep(void)
8117 * Make sure all delayed rcu free inodes are flushed before we
8121 if (btrfs_inode_cachep)
8122 kmem_cache_destroy(btrfs_inode_cachep);
8123 if (btrfs_trans_handle_cachep)
8124 kmem_cache_destroy(btrfs_trans_handle_cachep);
8125 if (btrfs_transaction_cachep)
8126 kmem_cache_destroy(btrfs_transaction_cachep);
8127 if (btrfs_path_cachep)
8128 kmem_cache_destroy(btrfs_path_cachep);
8129 if (btrfs_free_space_cachep)
8130 kmem_cache_destroy(btrfs_free_space_cachep);
8131 if (btrfs_delalloc_work_cachep)
8132 kmem_cache_destroy(btrfs_delalloc_work_cachep);
8135 int btrfs_init_cachep(void)
8137 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
8138 sizeof(struct btrfs_inode), 0,
8139 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
8140 if (!btrfs_inode_cachep)
8143 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
8144 sizeof(struct btrfs_trans_handle), 0,
8145 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8146 if (!btrfs_trans_handle_cachep)
8149 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
8150 sizeof(struct btrfs_transaction), 0,
8151 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8152 if (!btrfs_transaction_cachep)
8155 btrfs_path_cachep = kmem_cache_create("btrfs_path",
8156 sizeof(struct btrfs_path), 0,
8157 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8158 if (!btrfs_path_cachep)
8161 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
8162 sizeof(struct btrfs_free_space), 0,
8163 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8164 if (!btrfs_free_space_cachep)
8167 btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
8168 sizeof(struct btrfs_delalloc_work), 0,
8169 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
8171 if (!btrfs_delalloc_work_cachep)
8176 btrfs_destroy_cachep();
8180 static int btrfs_getattr(struct vfsmount *mnt,
8181 struct dentry *dentry, struct kstat *stat)
8184 struct inode *inode = dentry->d_inode;
8185 u32 blocksize = inode->i_sb->s_blocksize;
8187 generic_fillattr(inode, stat);
8188 stat->dev = BTRFS_I(inode)->root->anon_dev;
8189 stat->blksize = PAGE_CACHE_SIZE;
8191 spin_lock(&BTRFS_I(inode)->lock);
8192 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
8193 spin_unlock(&BTRFS_I(inode)->lock);
8194 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
8195 ALIGN(delalloc_bytes, blocksize)) >> 9;
8199 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
8200 struct inode *new_dir, struct dentry *new_dentry)
8202 struct btrfs_trans_handle *trans;
8203 struct btrfs_root *root = BTRFS_I(old_dir)->root;
8204 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
8205 struct inode *new_inode = new_dentry->d_inode;
8206 struct inode *old_inode = old_dentry->d_inode;
8207 struct timespec ctime = CURRENT_TIME;
8211 u64 old_ino = btrfs_ino(old_inode);
8213 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
8216 /* we only allow rename subvolume link between subvolumes */
8217 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
8220 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
8221 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
8224 if (S_ISDIR(old_inode->i_mode) && new_inode &&
8225 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
8229 /* check for collisions, even if the name isn't there */
8230 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
8231 new_dentry->d_name.name,
8232 new_dentry->d_name.len);
8235 if (ret == -EEXIST) {
8237 * eexist without a new_inode */
8238 if (WARN_ON(!new_inode)) {
8242 /* maybe -EOVERFLOW */
8249 * we're using rename to replace one file with another.
8250 * and the replacement file is large. Start IO on it now so
8251 * we don't add too much work to the end of the transaction
8253 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
8254 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
8255 filemap_flush(old_inode->i_mapping);
8257 /* close the racy window with snapshot create/destroy ioctl */
8258 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8259 down_read(&root->fs_info->subvol_sem);
8261 * We want to reserve the absolute worst case amount of items. So if
8262 * both inodes are subvols and we need to unlink them then that would
8263 * require 4 item modifications, but if they are both normal inodes it
8264 * would require 5 item modifications, so we'll assume their normal
8265 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
8266 * should cover the worst case number of items we'll modify.
8268 trans = btrfs_start_transaction(root, 11);
8269 if (IS_ERR(trans)) {
8270 ret = PTR_ERR(trans);
8275 btrfs_record_root_in_trans(trans, dest);
8277 ret = btrfs_set_inode_index(new_dir, &index);
8281 BTRFS_I(old_inode)->dir_index = 0ULL;
8282 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8283 /* force full log commit if subvolume involved. */
8284 root->fs_info->last_trans_log_full_commit = trans->transid;
8286 ret = btrfs_insert_inode_ref(trans, dest,
8287 new_dentry->d_name.name,
8288 new_dentry->d_name.len,
8290 btrfs_ino(new_dir), index);
8294 * this is an ugly little race, but the rename is required
8295 * to make sure that if we crash, the inode is either at the
8296 * old name or the new one. pinning the log transaction lets
8297 * us make sure we don't allow a log commit to come in after
8298 * we unlink the name but before we add the new name back in.
8300 btrfs_pin_log_trans(root);
8303 * make sure the inode gets flushed if it is replacing
8306 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
8307 btrfs_add_ordered_operation(trans, root, old_inode);
8309 inode_inc_iversion(old_dir);
8310 inode_inc_iversion(new_dir);
8311 inode_inc_iversion(old_inode);
8312 old_dir->i_ctime = old_dir->i_mtime = ctime;
8313 new_dir->i_ctime = new_dir->i_mtime = ctime;
8314 old_inode->i_ctime = ctime;
8316 if (old_dentry->d_parent != new_dentry->d_parent)
8317 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
8319 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8320 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
8321 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
8322 old_dentry->d_name.name,
8323 old_dentry->d_name.len);
8325 ret = __btrfs_unlink_inode(trans, root, old_dir,
8326 old_dentry->d_inode,
8327 old_dentry->d_name.name,
8328 old_dentry->d_name.len);
8330 ret = btrfs_update_inode(trans, root, old_inode);
8333 btrfs_abort_transaction(trans, root, ret);
8338 inode_inc_iversion(new_inode);
8339 new_inode->i_ctime = CURRENT_TIME;
8340 if (unlikely(btrfs_ino(new_inode) ==
8341 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
8342 root_objectid = BTRFS_I(new_inode)->location.objectid;
8343 ret = btrfs_unlink_subvol(trans, dest, new_dir,
8345 new_dentry->d_name.name,
8346 new_dentry->d_name.len);
8347 BUG_ON(new_inode->i_nlink == 0);
8349 ret = btrfs_unlink_inode(trans, dest, new_dir,
8350 new_dentry->d_inode,
8351 new_dentry->d_name.name,
8352 new_dentry->d_name.len);
8354 if (!ret && new_inode->i_nlink == 0)
8355 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
8357 btrfs_abort_transaction(trans, root, ret);
8362 ret = btrfs_add_link(trans, new_dir, old_inode,
8363 new_dentry->d_name.name,
8364 new_dentry->d_name.len, 0, index);
8366 btrfs_abort_transaction(trans, root, ret);
8370 if (old_inode->i_nlink == 1)
8371 BTRFS_I(old_inode)->dir_index = index;
8373 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
8374 struct dentry *parent = new_dentry->d_parent;
8375 btrfs_log_new_name(trans, old_inode, old_dir, parent);
8376 btrfs_end_log_trans(root);
8379 btrfs_end_transaction(trans, root);
8381 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8382 up_read(&root->fs_info->subvol_sem);
8387 static void btrfs_run_delalloc_work(struct btrfs_work_struct *work)
8389 struct btrfs_delalloc_work *delalloc_work;
8390 struct inode *inode;
8392 delalloc_work = container_of(work, struct btrfs_delalloc_work,
8394 inode = delalloc_work->inode;
8395 if (delalloc_work->wait) {
8396 btrfs_wait_ordered_range(inode, 0, (u64)-1);
8398 filemap_flush(inode->i_mapping);
8399 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
8400 &BTRFS_I(inode)->runtime_flags))
8401 filemap_flush(inode->i_mapping);
8404 if (delalloc_work->delay_iput)
8405 btrfs_add_delayed_iput(inode);
8408 complete(&delalloc_work->completion);
8411 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
8412 int wait, int delay_iput)
8414 struct btrfs_delalloc_work *work;
8416 work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
8420 init_completion(&work->completion);
8421 INIT_LIST_HEAD(&work->list);
8422 work->inode = inode;
8424 work->delay_iput = delay_iput;
8425 btrfs_init_work(&work->work, btrfs_run_delalloc_work, NULL, NULL);
8430 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
8432 wait_for_completion(&work->completion);
8433 kmem_cache_free(btrfs_delalloc_work_cachep, work);
8437 * some fairly slow code that needs optimization. This walks the list
8438 * of all the inodes with pending delalloc and forces them to disk.
8440 static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8442 struct btrfs_inode *binode;
8443 struct inode *inode;
8444 struct btrfs_delalloc_work *work, *next;
8445 struct list_head works;
8446 struct list_head splice;
8449 INIT_LIST_HEAD(&works);
8450 INIT_LIST_HEAD(&splice);
8452 spin_lock(&root->delalloc_lock);
8453 list_splice_init(&root->delalloc_inodes, &splice);
8454 while (!list_empty(&splice)) {
8455 binode = list_entry(splice.next, struct btrfs_inode,
8458 list_move_tail(&binode->delalloc_inodes,
8459 &root->delalloc_inodes);
8460 inode = igrab(&binode->vfs_inode);
8462 cond_resched_lock(&root->delalloc_lock);
8465 spin_unlock(&root->delalloc_lock);
8467 work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
8468 if (unlikely(!work)) {
8470 btrfs_add_delayed_iput(inode);
8476 list_add_tail(&work->list, &works);
8477 btrfs_queue_work(root->fs_info->flush_workers,
8481 spin_lock(&root->delalloc_lock);
8483 spin_unlock(&root->delalloc_lock);
8485 list_for_each_entry_safe(work, next, &works, list) {
8486 list_del_init(&work->list);
8487 btrfs_wait_and_free_delalloc_work(work);
8491 list_for_each_entry_safe(work, next, &works, list) {
8492 list_del_init(&work->list);
8493 btrfs_wait_and_free_delalloc_work(work);
8496 if (!list_empty_careful(&splice)) {
8497 spin_lock(&root->delalloc_lock);
8498 list_splice_tail(&splice, &root->delalloc_inodes);
8499 spin_unlock(&root->delalloc_lock);
8504 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8508 if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state))
8511 ret = __start_delalloc_inodes(root, delay_iput);
8513 * the filemap_flush will queue IO into the worker threads, but
8514 * we have to make sure the IO is actually started and that
8515 * ordered extents get created before we return
8517 atomic_inc(&root->fs_info->async_submit_draining);
8518 while (atomic_read(&root->fs_info->nr_async_submits) ||
8519 atomic_read(&root->fs_info->async_delalloc_pages)) {
8520 wait_event(root->fs_info->async_submit_wait,
8521 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
8522 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
8524 atomic_dec(&root->fs_info->async_submit_draining);
8528 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput)
8530 struct btrfs_root *root;
8531 struct list_head splice;
8534 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
8537 INIT_LIST_HEAD(&splice);
8539 spin_lock(&fs_info->delalloc_root_lock);
8540 list_splice_init(&fs_info->delalloc_roots, &splice);
8541 while (!list_empty(&splice)) {
8542 root = list_first_entry(&splice, struct btrfs_root,
8544 root = btrfs_grab_fs_root(root);
8546 list_move_tail(&root->delalloc_root,
8547 &fs_info->delalloc_roots);
8548 spin_unlock(&fs_info->delalloc_root_lock);
8550 ret = __start_delalloc_inodes(root, delay_iput);
8551 btrfs_put_fs_root(root);
8555 spin_lock(&fs_info->delalloc_root_lock);
8557 spin_unlock(&fs_info->delalloc_root_lock);
8559 atomic_inc(&fs_info->async_submit_draining);
8560 while (atomic_read(&fs_info->nr_async_submits) ||
8561 atomic_read(&fs_info->async_delalloc_pages)) {
8562 wait_event(fs_info->async_submit_wait,
8563 (atomic_read(&fs_info->nr_async_submits) == 0 &&
8564 atomic_read(&fs_info->async_delalloc_pages) == 0));
8566 atomic_dec(&fs_info->async_submit_draining);
8569 if (!list_empty_careful(&splice)) {
8570 spin_lock(&fs_info->delalloc_root_lock);
8571 list_splice_tail(&splice, &fs_info->delalloc_roots);
8572 spin_unlock(&fs_info->delalloc_root_lock);
8577 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
8578 const char *symname)
8580 struct btrfs_trans_handle *trans;
8581 struct btrfs_root *root = BTRFS_I(dir)->root;
8582 struct btrfs_path *path;
8583 struct btrfs_key key;
8584 struct inode *inode = NULL;
8592 struct btrfs_file_extent_item *ei;
8593 struct extent_buffer *leaf;
8595 name_len = strlen(symname);
8596 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
8597 return -ENAMETOOLONG;
8600 * 2 items for inode item and ref
8601 * 2 items for dir items
8602 * 1 item for xattr if selinux is on
8604 trans = btrfs_start_transaction(root, 5);
8606 return PTR_ERR(trans);
8608 err = btrfs_find_free_ino(root, &objectid);
8612 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
8613 dentry->d_name.len, btrfs_ino(dir), objectid,
8614 S_IFLNK|S_IRWXUGO, &index);
8615 if (IS_ERR(inode)) {
8616 err = PTR_ERR(inode);
8620 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
8627 * If the active LSM wants to access the inode during
8628 * d_instantiate it needs these. Smack checks to see
8629 * if the filesystem supports xattrs by looking at the
8632 inode->i_fop = &btrfs_file_operations;
8633 inode->i_op = &btrfs_file_inode_operations;
8635 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
8639 inode->i_mapping->a_ops = &btrfs_aops;
8640 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8641 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
8646 path = btrfs_alloc_path();
8652 key.objectid = btrfs_ino(inode);
8654 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
8655 datasize = btrfs_file_extent_calc_inline_size(name_len);
8656 err = btrfs_insert_empty_item(trans, root, path, &key,
8660 btrfs_free_path(path);
8663 leaf = path->nodes[0];
8664 ei = btrfs_item_ptr(leaf, path->slots[0],
8665 struct btrfs_file_extent_item);
8666 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
8667 btrfs_set_file_extent_type(leaf, ei,
8668 BTRFS_FILE_EXTENT_INLINE);
8669 btrfs_set_file_extent_encryption(leaf, ei, 0);
8670 btrfs_set_file_extent_compression(leaf, ei, 0);
8671 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
8672 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
8674 ptr = btrfs_file_extent_inline_start(ei);
8675 write_extent_buffer(leaf, symname, ptr, name_len);
8676 btrfs_mark_buffer_dirty(leaf);
8677 btrfs_free_path(path);
8679 inode->i_op = &btrfs_symlink_inode_operations;
8680 inode->i_mapping->a_ops = &btrfs_symlink_aops;
8681 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8682 inode_set_bytes(inode, name_len);
8683 btrfs_i_size_write(inode, name_len);
8684 err = btrfs_update_inode(trans, root, inode);
8690 d_instantiate(dentry, inode);
8691 btrfs_end_transaction(trans, root);
8693 inode_dec_link_count(inode);
8696 btrfs_btree_balance_dirty(root);
8700 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
8701 u64 start, u64 num_bytes, u64 min_size,
8702 loff_t actual_len, u64 *alloc_hint,
8703 struct btrfs_trans_handle *trans)
8705 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
8706 struct extent_map *em;
8707 struct btrfs_root *root = BTRFS_I(inode)->root;
8708 struct btrfs_key ins;
8709 u64 cur_offset = start;
8713 bool own_trans = true;
8717 while (num_bytes > 0) {
8719 trans = btrfs_start_transaction(root, 3);
8720 if (IS_ERR(trans)) {
8721 ret = PTR_ERR(trans);
8726 cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
8727 cur_bytes = max(cur_bytes, min_size);
8728 ret = btrfs_reserve_extent(root, cur_bytes, min_size, 0,
8729 *alloc_hint, &ins, 1);
8732 btrfs_end_transaction(trans, root);
8736 ret = insert_reserved_file_extent(trans, inode,
8737 cur_offset, ins.objectid,
8738 ins.offset, ins.offset,
8739 ins.offset, 0, 0, 0,
8740 BTRFS_FILE_EXTENT_PREALLOC);
8742 btrfs_free_reserved_extent(root, ins.objectid,
8744 btrfs_abort_transaction(trans, root, ret);
8746 btrfs_end_transaction(trans, root);
8749 btrfs_drop_extent_cache(inode, cur_offset,
8750 cur_offset + ins.offset -1, 0);
8752 em = alloc_extent_map();
8754 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
8755 &BTRFS_I(inode)->runtime_flags);
8759 em->start = cur_offset;
8760 em->orig_start = cur_offset;
8761 em->len = ins.offset;
8762 em->block_start = ins.objectid;
8763 em->block_len = ins.offset;
8764 em->orig_block_len = ins.offset;
8765 em->ram_bytes = ins.offset;
8766 em->bdev = root->fs_info->fs_devices->latest_bdev;
8767 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
8768 em->generation = trans->transid;
8771 write_lock(&em_tree->lock);
8772 ret = add_extent_mapping(em_tree, em, 1);
8773 write_unlock(&em_tree->lock);
8776 btrfs_drop_extent_cache(inode, cur_offset,
8777 cur_offset + ins.offset - 1,
8780 free_extent_map(em);
8782 num_bytes -= ins.offset;
8783 cur_offset += ins.offset;
8784 *alloc_hint = ins.objectid + ins.offset;
8786 inode_inc_iversion(inode);
8787 inode->i_ctime = CURRENT_TIME;
8788 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
8789 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
8790 (actual_len > inode->i_size) &&
8791 (cur_offset > inode->i_size)) {
8792 if (cur_offset > actual_len)
8793 i_size = actual_len;
8795 i_size = cur_offset;
8796 i_size_write(inode, i_size);
8797 btrfs_ordered_update_i_size(inode, i_size, NULL);
8800 ret = btrfs_update_inode(trans, root, inode);
8803 btrfs_abort_transaction(trans, root, ret);
8805 btrfs_end_transaction(trans, root);
8810 btrfs_end_transaction(trans, root);
8815 int btrfs_prealloc_file_range(struct inode *inode, int mode,
8816 u64 start, u64 num_bytes, u64 min_size,
8817 loff_t actual_len, u64 *alloc_hint)
8819 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8820 min_size, actual_len, alloc_hint,
8824 int btrfs_prealloc_file_range_trans(struct inode *inode,
8825 struct btrfs_trans_handle *trans, int mode,
8826 u64 start, u64 num_bytes, u64 min_size,
8827 loff_t actual_len, u64 *alloc_hint)
8829 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8830 min_size, actual_len, alloc_hint, trans);
8833 static int btrfs_set_page_dirty(struct page *page)
8835 return __set_page_dirty_nobuffers(page);
8838 static int btrfs_permission(struct inode *inode, int mask)
8840 struct btrfs_root *root = BTRFS_I(inode)->root;
8841 umode_t mode = inode->i_mode;
8843 if (mask & MAY_WRITE &&
8844 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
8845 if (btrfs_root_readonly(root))
8847 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
8850 return generic_permission(inode, mask);
8853 static const struct inode_operations btrfs_dir_inode_operations = {
8854 .getattr = btrfs_getattr,
8855 .lookup = btrfs_lookup,
8856 .create = btrfs_create,
8857 .unlink = btrfs_unlink,
8859 .mkdir = btrfs_mkdir,
8860 .rmdir = btrfs_rmdir,
8861 .rename = btrfs_rename,
8862 .symlink = btrfs_symlink,
8863 .setattr = btrfs_setattr,
8864 .mknod = btrfs_mknod,
8865 .setxattr = btrfs_setxattr,
8866 .getxattr = btrfs_getxattr,
8867 .listxattr = btrfs_listxattr,
8868 .removexattr = btrfs_removexattr,
8869 .permission = btrfs_permission,
8870 .get_acl = btrfs_get_acl,
8871 .update_time = btrfs_update_time,
8873 static const struct inode_operations btrfs_dir_ro_inode_operations = {
8874 .lookup = btrfs_lookup,
8875 .permission = btrfs_permission,
8876 .get_acl = btrfs_get_acl,
8877 .update_time = btrfs_update_time,
8880 static const struct file_operations btrfs_dir_file_operations = {
8881 .llseek = generic_file_llseek,
8882 .read = generic_read_dir,
8883 .iterate = btrfs_real_readdir,
8884 .unlocked_ioctl = btrfs_ioctl,
8885 #ifdef CONFIG_COMPAT
8886 .compat_ioctl = btrfs_ioctl,
8888 .release = btrfs_release_file,
8889 .fsync = btrfs_sync_file,
8892 static struct extent_io_ops btrfs_extent_io_ops = {
8893 .fill_delalloc = run_delalloc_range,
8894 .submit_bio_hook = btrfs_submit_bio_hook,
8895 .merge_bio_hook = btrfs_merge_bio_hook,
8896 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
8897 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
8898 .writepage_start_hook = btrfs_writepage_start_hook,
8899 .set_bit_hook = btrfs_set_bit_hook,
8900 .clear_bit_hook = btrfs_clear_bit_hook,
8901 .merge_extent_hook = btrfs_merge_extent_hook,
8902 .split_extent_hook = btrfs_split_extent_hook,
8906 * btrfs doesn't support the bmap operation because swapfiles
8907 * use bmap to make a mapping of extents in the file. They assume
8908 * these extents won't change over the life of the file and they
8909 * use the bmap result to do IO directly to the drive.
8911 * the btrfs bmap call would return logical addresses that aren't
8912 * suitable for IO and they also will change frequently as COW
8913 * operations happen. So, swapfile + btrfs == corruption.
8915 * For now we're avoiding this by dropping bmap.
8917 static const struct address_space_operations btrfs_aops = {
8918 .readpage = btrfs_readpage,
8919 .writepage = btrfs_writepage,
8920 .writepages = btrfs_writepages,
8921 .readpages = btrfs_readpages,
8922 .direct_IO = btrfs_direct_IO,
8923 .invalidatepage = btrfs_invalidatepage,
8924 .releasepage = btrfs_releasepage,
8925 .set_page_dirty = btrfs_set_page_dirty,
8926 .error_remove_page = generic_error_remove_page,
8929 static const struct address_space_operations btrfs_symlink_aops = {
8930 .readpage = btrfs_readpage,
8931 .writepage = btrfs_writepage,
8932 .invalidatepage = btrfs_invalidatepage,
8933 .releasepage = btrfs_releasepage,
8936 static const struct inode_operations btrfs_file_inode_operations = {
8937 .getattr = btrfs_getattr,
8938 .setattr = btrfs_setattr,
8939 .setxattr = btrfs_setxattr,
8940 .getxattr = btrfs_getxattr,
8941 .listxattr = btrfs_listxattr,
8942 .removexattr = btrfs_removexattr,
8943 .permission = btrfs_permission,
8944 .fiemap = btrfs_fiemap,
8945 .get_acl = btrfs_get_acl,
8946 .update_time = btrfs_update_time,
8948 static const struct inode_operations btrfs_special_inode_operations = {
8949 .getattr = btrfs_getattr,
8950 .setattr = btrfs_setattr,
8951 .permission = btrfs_permission,
8952 .setxattr = btrfs_setxattr,
8953 .getxattr = btrfs_getxattr,
8954 .listxattr = btrfs_listxattr,
8955 .removexattr = btrfs_removexattr,
8956 .get_acl = btrfs_get_acl,
8957 .update_time = btrfs_update_time,
8959 static const struct inode_operations btrfs_symlink_inode_operations = {
8960 .readlink = generic_readlink,
8961 .follow_link = page_follow_link_light,
8962 .put_link = page_put_link,
8963 .getattr = btrfs_getattr,
8964 .setattr = btrfs_setattr,
8965 .permission = btrfs_permission,
8966 .setxattr = btrfs_setxattr,
8967 .getxattr = btrfs_getxattr,
8968 .listxattr = btrfs_listxattr,
8969 .removexattr = btrfs_removexattr,
8970 .get_acl = btrfs_get_acl,
8971 .update_time = btrfs_update_time,
8974 const struct dentry_operations btrfs_dentry_operations = {
8975 .d_delete = btrfs_dentry_delete,
8976 .d_release = btrfs_dentry_release,