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 {
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 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)) {
870 num_bytes = ALIGN(end - start + 1, blocksize);
871 num_bytes = max(blocksize, num_bytes);
872 disk_num_bytes = num_bytes;
874 /* if this is a small write inside eof, kick off defrag */
875 if (num_bytes < 64 * 1024 &&
876 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
877 btrfs_add_inode_defrag(NULL, inode);
880 /* lets try to make an inline extent */
881 ret = cow_file_range_inline(root, inode, start, end, 0, 0,
884 extent_clear_unlock_delalloc(inode, start, end, NULL,
885 EXTENT_LOCKED | EXTENT_DELALLOC |
886 EXTENT_DEFRAG, PAGE_UNLOCK |
887 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
890 *nr_written = *nr_written +
891 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
894 } else if (ret < 0) {
899 BUG_ON(disk_num_bytes >
900 btrfs_super_total_bytes(root->fs_info->super_copy));
902 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
903 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
905 while (disk_num_bytes > 0) {
908 cur_alloc_size = disk_num_bytes;
909 ret = btrfs_reserve_extent(root, cur_alloc_size,
910 root->sectorsize, 0, alloc_hint,
915 em = alloc_extent_map();
921 em->orig_start = em->start;
922 ram_size = ins.offset;
923 em->len = ins.offset;
924 em->mod_start = em->start;
925 em->mod_len = em->len;
927 em->block_start = ins.objectid;
928 em->block_len = ins.offset;
929 em->orig_block_len = ins.offset;
930 em->ram_bytes = ram_size;
931 em->bdev = root->fs_info->fs_devices->latest_bdev;
932 set_bit(EXTENT_FLAG_PINNED, &em->flags);
936 write_lock(&em_tree->lock);
937 ret = add_extent_mapping(em_tree, em, 1);
938 write_unlock(&em_tree->lock);
939 if (ret != -EEXIST) {
943 btrfs_drop_extent_cache(inode, start,
944 start + ram_size - 1, 0);
949 cur_alloc_size = ins.offset;
950 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
951 ram_size, cur_alloc_size, 0);
955 if (root->root_key.objectid ==
956 BTRFS_DATA_RELOC_TREE_OBJECTID) {
957 ret = btrfs_reloc_clone_csums(inode, start,
963 if (disk_num_bytes < cur_alloc_size)
966 /* we're not doing compressed IO, don't unlock the first
967 * page (which the caller expects to stay locked), don't
968 * clear any dirty bits and don't set any writeback bits
970 * Do set the Private2 bit so we know this page was properly
971 * setup for writepage
973 op = unlock ? PAGE_UNLOCK : 0;
974 op |= PAGE_SET_PRIVATE2;
976 extent_clear_unlock_delalloc(inode, start,
977 start + ram_size - 1, locked_page,
978 EXTENT_LOCKED | EXTENT_DELALLOC,
980 disk_num_bytes -= cur_alloc_size;
981 num_bytes -= cur_alloc_size;
982 alloc_hint = ins.objectid + ins.offset;
983 start += cur_alloc_size;
989 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
991 extent_clear_unlock_delalloc(inode, start, end, locked_page,
992 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
993 EXTENT_DELALLOC | EXTENT_DEFRAG,
994 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
995 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK);
1000 * work queue call back to started compression on a file and pages
1002 static noinline void async_cow_start(struct btrfs_work *work)
1004 struct async_cow *async_cow;
1006 async_cow = container_of(work, struct async_cow, work);
1008 compress_file_range(async_cow->inode, async_cow->locked_page,
1009 async_cow->start, async_cow->end, async_cow,
1011 if (num_added == 0) {
1012 btrfs_add_delayed_iput(async_cow->inode);
1013 async_cow->inode = NULL;
1018 * work queue call back to submit previously compressed pages
1020 static noinline void async_cow_submit(struct btrfs_work *work)
1022 struct async_cow *async_cow;
1023 struct btrfs_root *root;
1024 unsigned long nr_pages;
1026 async_cow = container_of(work, struct async_cow, work);
1028 root = async_cow->root;
1029 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
1032 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
1034 waitqueue_active(&root->fs_info->async_submit_wait))
1035 wake_up(&root->fs_info->async_submit_wait);
1037 if (async_cow->inode)
1038 submit_compressed_extents(async_cow->inode, async_cow);
1041 static noinline void async_cow_free(struct btrfs_work *work)
1043 struct async_cow *async_cow;
1044 async_cow = container_of(work, struct async_cow, work);
1045 if (async_cow->inode)
1046 btrfs_add_delayed_iput(async_cow->inode);
1050 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1051 u64 start, u64 end, int *page_started,
1052 unsigned long *nr_written)
1054 struct async_cow *async_cow;
1055 struct btrfs_root *root = BTRFS_I(inode)->root;
1056 unsigned long nr_pages;
1058 int limit = 10 * 1024 * 1024;
1060 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1061 1, 0, NULL, GFP_NOFS);
1062 while (start < end) {
1063 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1064 BUG_ON(!async_cow); /* -ENOMEM */
1065 async_cow->inode = igrab(inode);
1066 async_cow->root = root;
1067 async_cow->locked_page = locked_page;
1068 async_cow->start = start;
1070 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
1073 cur_end = min(end, start + 512 * 1024 - 1);
1075 async_cow->end = cur_end;
1076 INIT_LIST_HEAD(&async_cow->extents);
1078 async_cow->work.func = async_cow_start;
1079 async_cow->work.ordered_func = async_cow_submit;
1080 async_cow->work.ordered_free = async_cow_free;
1081 async_cow->work.flags = 0;
1083 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1085 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1087 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1090 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1091 wait_event(root->fs_info->async_submit_wait,
1092 (atomic_read(&root->fs_info->async_delalloc_pages) <
1096 while (atomic_read(&root->fs_info->async_submit_draining) &&
1097 atomic_read(&root->fs_info->async_delalloc_pages)) {
1098 wait_event(root->fs_info->async_submit_wait,
1099 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1103 *nr_written += nr_pages;
1104 start = cur_end + 1;
1110 static noinline int csum_exist_in_range(struct btrfs_root *root,
1111 u64 bytenr, u64 num_bytes)
1114 struct btrfs_ordered_sum *sums;
1117 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1118 bytenr + num_bytes - 1, &list, 0);
1119 if (ret == 0 && list_empty(&list))
1122 while (!list_empty(&list)) {
1123 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1124 list_del(&sums->list);
1131 * when nowcow writeback call back. This checks for snapshots or COW copies
1132 * of the extents that exist in the file, and COWs the file as required.
1134 * If no cow copies or snapshots exist, we write directly to the existing
1137 static noinline int run_delalloc_nocow(struct inode *inode,
1138 struct page *locked_page,
1139 u64 start, u64 end, int *page_started, int force,
1140 unsigned long *nr_written)
1142 struct btrfs_root *root = BTRFS_I(inode)->root;
1143 struct btrfs_trans_handle *trans;
1144 struct extent_buffer *leaf;
1145 struct btrfs_path *path;
1146 struct btrfs_file_extent_item *fi;
1147 struct btrfs_key found_key;
1162 u64 ino = btrfs_ino(inode);
1164 path = btrfs_alloc_path();
1166 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1167 EXTENT_LOCKED | EXTENT_DELALLOC |
1168 EXTENT_DO_ACCOUNTING |
1169 EXTENT_DEFRAG, PAGE_UNLOCK |
1171 PAGE_SET_WRITEBACK |
1172 PAGE_END_WRITEBACK);
1176 nolock = btrfs_is_free_space_inode(inode);
1179 trans = btrfs_join_transaction_nolock(root);
1181 trans = btrfs_join_transaction(root);
1183 if (IS_ERR(trans)) {
1184 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1185 EXTENT_LOCKED | EXTENT_DELALLOC |
1186 EXTENT_DO_ACCOUNTING |
1187 EXTENT_DEFRAG, PAGE_UNLOCK |
1189 PAGE_SET_WRITEBACK |
1190 PAGE_END_WRITEBACK);
1191 btrfs_free_path(path);
1192 return PTR_ERR(trans);
1195 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1197 cow_start = (u64)-1;
1200 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1204 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1205 leaf = path->nodes[0];
1206 btrfs_item_key_to_cpu(leaf, &found_key,
1207 path->slots[0] - 1);
1208 if (found_key.objectid == ino &&
1209 found_key.type == BTRFS_EXTENT_DATA_KEY)
1214 leaf = path->nodes[0];
1215 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1216 ret = btrfs_next_leaf(root, path);
1221 leaf = path->nodes[0];
1227 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1229 if (found_key.objectid > ino ||
1230 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1231 found_key.offset > end)
1234 if (found_key.offset > cur_offset) {
1235 extent_end = found_key.offset;
1240 fi = btrfs_item_ptr(leaf, path->slots[0],
1241 struct btrfs_file_extent_item);
1242 extent_type = btrfs_file_extent_type(leaf, fi);
1244 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1245 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1246 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1247 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1248 extent_offset = btrfs_file_extent_offset(leaf, fi);
1249 extent_end = found_key.offset +
1250 btrfs_file_extent_num_bytes(leaf, fi);
1252 btrfs_file_extent_disk_num_bytes(leaf, fi);
1253 if (extent_end <= start) {
1257 if (disk_bytenr == 0)
1259 if (btrfs_file_extent_compression(leaf, fi) ||
1260 btrfs_file_extent_encryption(leaf, fi) ||
1261 btrfs_file_extent_other_encoding(leaf, fi))
1263 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1265 if (btrfs_extent_readonly(root, disk_bytenr))
1267 if (btrfs_cross_ref_exist(trans, root, ino,
1269 extent_offset, disk_bytenr))
1271 disk_bytenr += extent_offset;
1272 disk_bytenr += cur_offset - found_key.offset;
1273 num_bytes = min(end + 1, extent_end) - cur_offset;
1275 * force cow if csum exists in the range.
1276 * this ensure that csum for a given extent are
1277 * either valid or do not exist.
1279 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1282 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1283 extent_end = found_key.offset +
1284 btrfs_file_extent_inline_len(leaf, 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 work;
1754 static void btrfs_writepage_fixup_worker(struct btrfs_work *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 fixup->work.func = btrfs_writepage_fixup_worker;
1847 btrfs_queue_worker(&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 /* step 2: get inode */
2242 key.objectid = backref->inum;
2243 key.type = BTRFS_INODE_ITEM_KEY;
2246 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2247 if (IS_ERR(inode)) {
2248 srcu_read_unlock(&fs_info->subvol_srcu, index);
2252 srcu_read_unlock(&fs_info->subvol_srcu, index);
2254 /* step 3: relink backref */
2255 lock_start = backref->file_pos;
2256 lock_end = backref->file_pos + backref->num_bytes - 1;
2257 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2260 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2262 btrfs_put_ordered_extent(ordered);
2266 trans = btrfs_join_transaction(root);
2267 if (IS_ERR(trans)) {
2268 ret = PTR_ERR(trans);
2272 key.objectid = backref->inum;
2273 key.type = BTRFS_EXTENT_DATA_KEY;
2274 key.offset = backref->file_pos;
2276 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2279 } else if (ret > 0) {
2284 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2285 struct btrfs_file_extent_item);
2287 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2288 backref->generation)
2291 btrfs_release_path(path);
2293 start = backref->file_pos;
2294 if (backref->extent_offset < old->extent_offset + old->offset)
2295 start += old->extent_offset + old->offset -
2296 backref->extent_offset;
2298 len = min(backref->extent_offset + backref->num_bytes,
2299 old->extent_offset + old->offset + old->len);
2300 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2302 ret = btrfs_drop_extents(trans, root, inode, start,
2307 key.objectid = btrfs_ino(inode);
2308 key.type = BTRFS_EXTENT_DATA_KEY;
2311 path->leave_spinning = 1;
2313 struct btrfs_file_extent_item *fi;
2315 struct btrfs_key found_key;
2317 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2322 leaf = path->nodes[0];
2323 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2325 fi = btrfs_item_ptr(leaf, path->slots[0],
2326 struct btrfs_file_extent_item);
2327 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2329 if (extent_len + found_key.offset == start &&
2330 relink_is_mergable(leaf, fi, new)) {
2331 btrfs_set_file_extent_num_bytes(leaf, fi,
2333 btrfs_mark_buffer_dirty(leaf);
2334 inode_add_bytes(inode, len);
2340 btrfs_release_path(path);
2345 ret = btrfs_insert_empty_item(trans, root, path, &key,
2348 btrfs_abort_transaction(trans, root, ret);
2352 leaf = path->nodes[0];
2353 item = btrfs_item_ptr(leaf, path->slots[0],
2354 struct btrfs_file_extent_item);
2355 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2356 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2357 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2358 btrfs_set_file_extent_num_bytes(leaf, item, len);
2359 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2360 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2361 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2362 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2363 btrfs_set_file_extent_encryption(leaf, item, 0);
2364 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2366 btrfs_mark_buffer_dirty(leaf);
2367 inode_add_bytes(inode, len);
2368 btrfs_release_path(path);
2370 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2372 backref->root_id, backref->inum,
2373 new->file_pos, 0); /* start - extent_offset */
2375 btrfs_abort_transaction(trans, root, ret);
2381 btrfs_release_path(path);
2382 path->leave_spinning = 0;
2383 btrfs_end_transaction(trans, root);
2385 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2391 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new)
2393 struct old_sa_defrag_extent *old, *tmp;
2398 list_for_each_entry_safe(old, tmp, &new->head, list) {
2399 list_del(&old->list);
2405 static void relink_file_extents(struct new_sa_defrag_extent *new)
2407 struct btrfs_path *path;
2408 struct sa_defrag_extent_backref *backref;
2409 struct sa_defrag_extent_backref *prev = NULL;
2410 struct inode *inode;
2411 struct btrfs_root *root;
2412 struct rb_node *node;
2416 root = BTRFS_I(inode)->root;
2418 path = btrfs_alloc_path();
2422 if (!record_extent_backrefs(path, new)) {
2423 btrfs_free_path(path);
2426 btrfs_release_path(path);
2429 node = rb_first(&new->root);
2432 rb_erase(node, &new->root);
2434 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2436 ret = relink_extent_backref(path, prev, backref);
2449 btrfs_free_path(path);
2451 free_sa_defrag_extent(new);
2453 atomic_dec(&root->fs_info->defrag_running);
2454 wake_up(&root->fs_info->transaction_wait);
2457 static struct new_sa_defrag_extent *
2458 record_old_file_extents(struct inode *inode,
2459 struct btrfs_ordered_extent *ordered)
2461 struct btrfs_root *root = BTRFS_I(inode)->root;
2462 struct btrfs_path *path;
2463 struct btrfs_key key;
2464 struct old_sa_defrag_extent *old;
2465 struct new_sa_defrag_extent *new;
2468 new = kmalloc(sizeof(*new), GFP_NOFS);
2473 new->file_pos = ordered->file_offset;
2474 new->len = ordered->len;
2475 new->bytenr = ordered->start;
2476 new->disk_len = ordered->disk_len;
2477 new->compress_type = ordered->compress_type;
2478 new->root = RB_ROOT;
2479 INIT_LIST_HEAD(&new->head);
2481 path = btrfs_alloc_path();
2485 key.objectid = btrfs_ino(inode);
2486 key.type = BTRFS_EXTENT_DATA_KEY;
2487 key.offset = new->file_pos;
2489 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2492 if (ret > 0 && path->slots[0] > 0)
2495 /* find out all the old extents for the file range */
2497 struct btrfs_file_extent_item *extent;
2498 struct extent_buffer *l;
2507 slot = path->slots[0];
2509 if (slot >= btrfs_header_nritems(l)) {
2510 ret = btrfs_next_leaf(root, path);
2518 btrfs_item_key_to_cpu(l, &key, slot);
2520 if (key.objectid != btrfs_ino(inode))
2522 if (key.type != BTRFS_EXTENT_DATA_KEY)
2524 if (key.offset >= new->file_pos + new->len)
2527 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2529 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2530 if (key.offset + num_bytes < new->file_pos)
2533 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2537 extent_offset = btrfs_file_extent_offset(l, extent);
2539 old = kmalloc(sizeof(*old), GFP_NOFS);
2543 offset = max(new->file_pos, key.offset);
2544 end = min(new->file_pos + new->len, key.offset + num_bytes);
2546 old->bytenr = disk_bytenr;
2547 old->extent_offset = extent_offset;
2548 old->offset = offset - key.offset;
2549 old->len = end - offset;
2552 list_add_tail(&old->list, &new->head);
2558 btrfs_free_path(path);
2559 atomic_inc(&root->fs_info->defrag_running);
2564 btrfs_free_path(path);
2566 free_sa_defrag_extent(new);
2570 /* as ordered data IO finishes, this gets called so we can finish
2571 * an ordered extent if the range of bytes in the file it covers are
2574 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2576 struct inode *inode = ordered_extent->inode;
2577 struct btrfs_root *root = BTRFS_I(inode)->root;
2578 struct btrfs_trans_handle *trans = NULL;
2579 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2580 struct extent_state *cached_state = NULL;
2581 struct new_sa_defrag_extent *new = NULL;
2582 int compress_type = 0;
2584 u64 logical_len = ordered_extent->len;
2586 bool truncated = false;
2588 nolock = btrfs_is_free_space_inode(inode);
2590 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2595 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2597 logical_len = ordered_extent->truncated_len;
2598 /* Truncated the entire extent, don't bother adding */
2603 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2604 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2605 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2607 trans = btrfs_join_transaction_nolock(root);
2609 trans = btrfs_join_transaction(root);
2610 if (IS_ERR(trans)) {
2611 ret = PTR_ERR(trans);
2615 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2616 ret = btrfs_update_inode_fallback(trans, root, inode);
2617 if (ret) /* -ENOMEM or corruption */
2618 btrfs_abort_transaction(trans, root, ret);
2622 lock_extent_bits(io_tree, ordered_extent->file_offset,
2623 ordered_extent->file_offset + ordered_extent->len - 1,
2626 ret = test_range_bit(io_tree, ordered_extent->file_offset,
2627 ordered_extent->file_offset + ordered_extent->len - 1,
2628 EXTENT_DEFRAG, 1, cached_state);
2630 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2631 if (last_snapshot >= BTRFS_I(inode)->generation)
2632 /* the inode is shared */
2633 new = record_old_file_extents(inode, ordered_extent);
2635 clear_extent_bit(io_tree, ordered_extent->file_offset,
2636 ordered_extent->file_offset + ordered_extent->len - 1,
2637 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS);
2641 trans = btrfs_join_transaction_nolock(root);
2643 trans = btrfs_join_transaction(root);
2644 if (IS_ERR(trans)) {
2645 ret = PTR_ERR(trans);
2649 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2651 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
2652 compress_type = ordered_extent->compress_type;
2653 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2654 BUG_ON(compress_type);
2655 ret = btrfs_mark_extent_written(trans, inode,
2656 ordered_extent->file_offset,
2657 ordered_extent->file_offset +
2660 BUG_ON(root == root->fs_info->tree_root);
2661 ret = insert_reserved_file_extent(trans, inode,
2662 ordered_extent->file_offset,
2663 ordered_extent->start,
2664 ordered_extent->disk_len,
2665 logical_len, logical_len,
2666 compress_type, 0, 0,
2667 BTRFS_FILE_EXTENT_REG);
2669 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2670 ordered_extent->file_offset, ordered_extent->len,
2673 btrfs_abort_transaction(trans, root, ret);
2677 add_pending_csums(trans, inode, ordered_extent->file_offset,
2678 &ordered_extent->list);
2680 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2681 ret = btrfs_update_inode_fallback(trans, root, inode);
2682 if (ret) { /* -ENOMEM or corruption */
2683 btrfs_abort_transaction(trans, root, ret);
2688 unlock_extent_cached(io_tree, ordered_extent->file_offset,
2689 ordered_extent->file_offset +
2690 ordered_extent->len - 1, &cached_state, GFP_NOFS);
2692 if (root != root->fs_info->tree_root)
2693 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
2695 btrfs_end_transaction(trans, root);
2697 if (ret || truncated) {
2701 start = ordered_extent->file_offset + logical_len;
2703 start = ordered_extent->file_offset;
2704 end = ordered_extent->file_offset + ordered_extent->len - 1;
2705 clear_extent_uptodate(io_tree, start, end, NULL, GFP_NOFS);
2707 /* Drop the cache for the part of the extent we didn't write. */
2708 btrfs_drop_extent_cache(inode, start, end, 0);
2711 * If the ordered extent had an IOERR or something else went
2712 * wrong we need to return the space for this ordered extent
2713 * back to the allocator. We only free the extent in the
2714 * truncated case if we didn't write out the extent at all.
2716 if ((ret || !logical_len) &&
2717 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2718 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
2719 btrfs_free_reserved_extent(root, ordered_extent->start,
2720 ordered_extent->disk_len);
2725 * This needs to be done to make sure anybody waiting knows we are done
2726 * updating everything for this ordered extent.
2728 btrfs_remove_ordered_extent(inode, ordered_extent);
2730 /* for snapshot-aware defrag */
2733 free_sa_defrag_extent(new);
2734 atomic_dec(&root->fs_info->defrag_running);
2736 relink_file_extents(new);
2741 btrfs_put_ordered_extent(ordered_extent);
2742 /* once for the tree */
2743 btrfs_put_ordered_extent(ordered_extent);
2748 static void finish_ordered_fn(struct btrfs_work *work)
2750 struct btrfs_ordered_extent *ordered_extent;
2751 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2752 btrfs_finish_ordered_io(ordered_extent);
2755 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
2756 struct extent_state *state, int uptodate)
2758 struct inode *inode = page->mapping->host;
2759 struct btrfs_root *root = BTRFS_I(inode)->root;
2760 struct btrfs_ordered_extent *ordered_extent = NULL;
2761 struct btrfs_workers *workers;
2763 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2765 ClearPagePrivate2(page);
2766 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2767 end - start + 1, uptodate))
2770 ordered_extent->work.func = finish_ordered_fn;
2771 ordered_extent->work.flags = 0;
2773 if (btrfs_is_free_space_inode(inode))
2774 workers = &root->fs_info->endio_freespace_worker;
2776 workers = &root->fs_info->endio_write_workers;
2777 btrfs_queue_worker(workers, &ordered_extent->work);
2783 * when reads are done, we need to check csums to verify the data is correct
2784 * if there's a match, we allow the bio to finish. If not, the code in
2785 * extent_io.c will try to find good copies for us.
2787 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
2788 u64 phy_offset, struct page *page,
2789 u64 start, u64 end, int mirror)
2791 size_t offset = start - page_offset(page);
2792 struct inode *inode = page->mapping->host;
2793 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2795 struct btrfs_root *root = BTRFS_I(inode)->root;
2798 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
2799 DEFAULT_RATELIMIT_BURST);
2801 if (PageChecked(page)) {
2802 ClearPageChecked(page);
2806 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
2809 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
2810 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
2811 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
2816 phy_offset >>= inode->i_sb->s_blocksize_bits;
2817 csum_expected = *(((u32 *)io_bio->csum) + phy_offset);
2819 kaddr = kmap_atomic(page);
2820 csum = btrfs_csum_data(kaddr + offset, csum, end - start + 1);
2821 btrfs_csum_final(csum, (char *)&csum);
2822 if (csum != csum_expected)
2825 kunmap_atomic(kaddr);
2830 if (__ratelimit(&_rs))
2831 btrfs_info(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
2832 btrfs_ino(page->mapping->host), start, csum, csum_expected);
2833 memset(kaddr + offset, 1, end - start + 1);
2834 flush_dcache_page(page);
2835 kunmap_atomic(kaddr);
2836 if (csum_expected == 0)
2841 struct delayed_iput {
2842 struct list_head list;
2843 struct inode *inode;
2846 /* JDM: If this is fs-wide, why can't we add a pointer to
2847 * btrfs_inode instead and avoid the allocation? */
2848 void btrfs_add_delayed_iput(struct inode *inode)
2850 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2851 struct delayed_iput *delayed;
2853 if (atomic_add_unless(&inode->i_count, -1, 1))
2856 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2857 delayed->inode = inode;
2859 spin_lock(&fs_info->delayed_iput_lock);
2860 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2861 spin_unlock(&fs_info->delayed_iput_lock);
2864 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2867 struct btrfs_fs_info *fs_info = root->fs_info;
2868 struct delayed_iput *delayed;
2871 spin_lock(&fs_info->delayed_iput_lock);
2872 empty = list_empty(&fs_info->delayed_iputs);
2873 spin_unlock(&fs_info->delayed_iput_lock);
2877 spin_lock(&fs_info->delayed_iput_lock);
2878 list_splice_init(&fs_info->delayed_iputs, &list);
2879 spin_unlock(&fs_info->delayed_iput_lock);
2881 while (!list_empty(&list)) {
2882 delayed = list_entry(list.next, struct delayed_iput, list);
2883 list_del(&delayed->list);
2884 iput(delayed->inode);
2890 * This is called in transaction commit time. If there are no orphan
2891 * files in the subvolume, it removes orphan item and frees block_rsv
2894 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2895 struct btrfs_root *root)
2897 struct btrfs_block_rsv *block_rsv;
2900 if (atomic_read(&root->orphan_inodes) ||
2901 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2904 spin_lock(&root->orphan_lock);
2905 if (atomic_read(&root->orphan_inodes)) {
2906 spin_unlock(&root->orphan_lock);
2910 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) {
2911 spin_unlock(&root->orphan_lock);
2915 block_rsv = root->orphan_block_rsv;
2916 root->orphan_block_rsv = NULL;
2917 spin_unlock(&root->orphan_lock);
2919 if (root->orphan_item_inserted &&
2920 btrfs_root_refs(&root->root_item) > 0) {
2921 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2922 root->root_key.objectid);
2924 btrfs_abort_transaction(trans, root, ret);
2926 root->orphan_item_inserted = 0;
2930 WARN_ON(block_rsv->size > 0);
2931 btrfs_free_block_rsv(root, block_rsv);
2936 * This creates an orphan entry for the given inode in case something goes
2937 * wrong in the middle of an unlink/truncate.
2939 * NOTE: caller of this function should reserve 5 units of metadata for
2942 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2944 struct btrfs_root *root = BTRFS_I(inode)->root;
2945 struct btrfs_block_rsv *block_rsv = NULL;
2950 if (!root->orphan_block_rsv) {
2951 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
2956 spin_lock(&root->orphan_lock);
2957 if (!root->orphan_block_rsv) {
2958 root->orphan_block_rsv = block_rsv;
2959 } else if (block_rsv) {
2960 btrfs_free_block_rsv(root, block_rsv);
2964 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2965 &BTRFS_I(inode)->runtime_flags)) {
2968 * For proper ENOSPC handling, we should do orphan
2969 * cleanup when mounting. But this introduces backward
2970 * compatibility issue.
2972 if (!xchg(&root->orphan_item_inserted, 1))
2978 atomic_inc(&root->orphan_inodes);
2981 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2982 &BTRFS_I(inode)->runtime_flags))
2984 spin_unlock(&root->orphan_lock);
2986 /* grab metadata reservation from transaction handle */
2988 ret = btrfs_orphan_reserve_metadata(trans, inode);
2989 BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */
2992 /* insert an orphan item to track this unlinked/truncated file */
2994 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2996 atomic_dec(&root->orphan_inodes);
2998 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2999 &BTRFS_I(inode)->runtime_flags);
3000 btrfs_orphan_release_metadata(inode);
3002 if (ret != -EEXIST) {
3003 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3004 &BTRFS_I(inode)->runtime_flags);
3005 btrfs_abort_transaction(trans, root, ret);
3012 /* insert an orphan item to track subvolume contains orphan files */
3014 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
3015 root->root_key.objectid);
3016 if (ret && ret != -EEXIST) {
3017 btrfs_abort_transaction(trans, root, ret);
3025 * We have done the truncate/delete so we can go ahead and remove the orphan
3026 * item for this particular inode.
3028 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3029 struct inode *inode)
3031 struct btrfs_root *root = BTRFS_I(inode)->root;
3032 int delete_item = 0;
3033 int release_rsv = 0;
3036 spin_lock(&root->orphan_lock);
3037 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3038 &BTRFS_I(inode)->runtime_flags))
3041 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3042 &BTRFS_I(inode)->runtime_flags))
3044 spin_unlock(&root->orphan_lock);
3047 atomic_dec(&root->orphan_inodes);
3049 ret = btrfs_del_orphan_item(trans, root,
3054 btrfs_orphan_release_metadata(inode);
3060 * this cleans up any orphans that may be left on the list from the last use
3063 int btrfs_orphan_cleanup(struct btrfs_root *root)
3065 struct btrfs_path *path;
3066 struct extent_buffer *leaf;
3067 struct btrfs_key key, found_key;
3068 struct btrfs_trans_handle *trans;
3069 struct inode *inode;
3070 u64 last_objectid = 0;
3071 int ret = 0, nr_unlink = 0, nr_truncate = 0;
3073 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3076 path = btrfs_alloc_path();
3083 key.objectid = BTRFS_ORPHAN_OBJECTID;
3084 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
3085 key.offset = (u64)-1;
3088 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3093 * if ret == 0 means we found what we were searching for, which
3094 * is weird, but possible, so only screw with path if we didn't
3095 * find the key and see if we have stuff that matches
3099 if (path->slots[0] == 0)
3104 /* pull out the item */
3105 leaf = path->nodes[0];
3106 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3108 /* make sure the item matches what we want */
3109 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3111 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
3114 /* release the path since we're done with it */
3115 btrfs_release_path(path);
3118 * this is where we are basically btrfs_lookup, without the
3119 * crossing root thing. we store the inode number in the
3120 * offset of the orphan item.
3123 if (found_key.offset == last_objectid) {
3124 btrfs_err(root->fs_info,
3125 "Error removing orphan entry, stopping orphan cleanup");
3130 last_objectid = found_key.offset;
3132 found_key.objectid = found_key.offset;
3133 found_key.type = BTRFS_INODE_ITEM_KEY;
3134 found_key.offset = 0;
3135 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
3136 ret = PTR_ERR_OR_ZERO(inode);
3137 if (ret && ret != -ESTALE)
3140 if (ret == -ESTALE && root == root->fs_info->tree_root) {
3141 struct btrfs_root *dead_root;
3142 struct btrfs_fs_info *fs_info = root->fs_info;
3143 int is_dead_root = 0;
3146 * this is an orphan in the tree root. Currently these
3147 * could come from 2 sources:
3148 * a) a snapshot deletion in progress
3149 * b) a free space cache inode
3150 * We need to distinguish those two, as the snapshot
3151 * orphan must not get deleted.
3152 * find_dead_roots already ran before us, so if this
3153 * is a snapshot deletion, we should find the root
3154 * in the dead_roots list
3156 spin_lock(&fs_info->trans_lock);
3157 list_for_each_entry(dead_root, &fs_info->dead_roots,
3159 if (dead_root->root_key.objectid ==
3160 found_key.objectid) {
3165 spin_unlock(&fs_info->trans_lock);
3167 /* prevent this orphan from being found again */
3168 key.offset = found_key.objectid - 1;
3173 * Inode is already gone but the orphan item is still there,
3174 * kill the orphan item.
3176 if (ret == -ESTALE) {
3177 trans = btrfs_start_transaction(root, 1);
3178 if (IS_ERR(trans)) {
3179 ret = PTR_ERR(trans);
3182 btrfs_debug(root->fs_info, "auto deleting %Lu",
3183 found_key.objectid);
3184 ret = btrfs_del_orphan_item(trans, root,
3185 found_key.objectid);
3186 btrfs_end_transaction(trans, root);
3193 * add this inode to the orphan list so btrfs_orphan_del does
3194 * the proper thing when we hit it
3196 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3197 &BTRFS_I(inode)->runtime_flags);
3198 atomic_inc(&root->orphan_inodes);
3200 /* if we have links, this was a truncate, lets do that */
3201 if (inode->i_nlink) {
3202 if (WARN_ON(!S_ISREG(inode->i_mode))) {
3208 /* 1 for the orphan item deletion. */
3209 trans = btrfs_start_transaction(root, 1);
3210 if (IS_ERR(trans)) {
3212 ret = PTR_ERR(trans);
3215 ret = btrfs_orphan_add(trans, inode);
3216 btrfs_end_transaction(trans, root);
3222 ret = btrfs_truncate(inode);
3224 btrfs_orphan_del(NULL, inode);
3229 /* this will do delete_inode and everything for us */
3234 /* release the path since we're done with it */
3235 btrfs_release_path(path);
3237 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3239 if (root->orphan_block_rsv)
3240 btrfs_block_rsv_release(root, root->orphan_block_rsv,
3243 if (root->orphan_block_rsv || root->orphan_item_inserted) {
3244 trans = btrfs_join_transaction(root);
3246 btrfs_end_transaction(trans, root);
3250 btrfs_debug(root->fs_info, "unlinked %d orphans", nr_unlink);
3252 btrfs_debug(root->fs_info, "truncated %d orphans", nr_truncate);
3256 btrfs_crit(root->fs_info,
3257 "could not do orphan cleanup %d", ret);
3258 btrfs_free_path(path);
3263 * very simple check to peek ahead in the leaf looking for xattrs. If we
3264 * don't find any xattrs, we know there can't be any acls.
3266 * slot is the slot the inode is in, objectid is the objectid of the inode
3268 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3269 int slot, u64 objectid,
3270 int *first_xattr_slot)
3272 u32 nritems = btrfs_header_nritems(leaf);
3273 struct btrfs_key found_key;
3274 static u64 xattr_access = 0;
3275 static u64 xattr_default = 0;
3278 if (!xattr_access) {
3279 xattr_access = btrfs_name_hash(POSIX_ACL_XATTR_ACCESS,
3280 strlen(POSIX_ACL_XATTR_ACCESS));
3281 xattr_default = btrfs_name_hash(POSIX_ACL_XATTR_DEFAULT,
3282 strlen(POSIX_ACL_XATTR_DEFAULT));
3286 *first_xattr_slot = -1;
3287 while (slot < nritems) {
3288 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3290 /* we found a different objectid, there must not be acls */
3291 if (found_key.objectid != objectid)
3294 /* we found an xattr, assume we've got an acl */
3295 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3296 if (*first_xattr_slot == -1)
3297 *first_xattr_slot = slot;
3298 if (found_key.offset == xattr_access ||
3299 found_key.offset == xattr_default)
3304 * we found a key greater than an xattr key, there can't
3305 * be any acls later on
3307 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3314 * it goes inode, inode backrefs, xattrs, extents,
3315 * so if there are a ton of hard links to an inode there can
3316 * be a lot of backrefs. Don't waste time searching too hard,
3317 * this is just an optimization
3322 /* we hit the end of the leaf before we found an xattr or
3323 * something larger than an xattr. We have to assume the inode
3326 if (*first_xattr_slot == -1)
3327 *first_xattr_slot = slot;
3332 * read an inode from the btree into the in-memory inode
3334 static void btrfs_read_locked_inode(struct inode *inode)
3336 struct btrfs_path *path;
3337 struct extent_buffer *leaf;
3338 struct btrfs_inode_item *inode_item;
3339 struct btrfs_timespec *tspec;
3340 struct btrfs_root *root = BTRFS_I(inode)->root;
3341 struct btrfs_key location;
3346 bool filled = false;
3347 int first_xattr_slot;
3349 ret = btrfs_fill_inode(inode, &rdev);
3353 path = btrfs_alloc_path();
3357 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3359 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3363 leaf = path->nodes[0];
3368 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3369 struct btrfs_inode_item);
3370 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3371 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3372 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3373 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3374 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
3376 tspec = btrfs_inode_atime(inode_item);
3377 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3378 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3380 tspec = btrfs_inode_mtime(inode_item);
3381 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3382 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3384 tspec = btrfs_inode_ctime(inode_item);
3385 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3386 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3388 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3389 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3390 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3393 * If we were modified in the current generation and evicted from memory
3394 * and then re-read we need to do a full sync since we don't have any
3395 * idea about which extents were modified before we were evicted from
3398 if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
3399 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3400 &BTRFS_I(inode)->runtime_flags);
3402 inode->i_version = btrfs_inode_sequence(leaf, inode_item);
3403 inode->i_generation = BTRFS_I(inode)->generation;
3405 rdev = btrfs_inode_rdev(leaf, inode_item);
3407 BTRFS_I(inode)->index_cnt = (u64)-1;
3408 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3412 if (inode->i_nlink != 1 ||
3413 path->slots[0] >= btrfs_header_nritems(leaf))
3416 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]);
3417 if (location.objectid != btrfs_ino(inode))
3420 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
3421 if (location.type == BTRFS_INODE_REF_KEY) {
3422 struct btrfs_inode_ref *ref;
3424 ref = (struct btrfs_inode_ref *)ptr;
3425 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref);
3426 } else if (location.type == BTRFS_INODE_EXTREF_KEY) {
3427 struct btrfs_inode_extref *extref;
3429 extref = (struct btrfs_inode_extref *)ptr;
3430 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf,
3435 * try to precache a NULL acl entry for files that don't have
3436 * any xattrs or acls
3438 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3439 btrfs_ino(inode), &first_xattr_slot);
3440 if (first_xattr_slot != -1) {
3441 path->slots[0] = first_xattr_slot;
3442 ret = btrfs_load_inode_props(inode, path);
3444 btrfs_err(root->fs_info,
3445 "error loading props for ino %llu (root %llu): %d\n",
3447 root->root_key.objectid, ret);
3449 btrfs_free_path(path);
3452 cache_no_acl(inode);
3454 switch (inode->i_mode & S_IFMT) {
3456 inode->i_mapping->a_ops = &btrfs_aops;
3457 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3458 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3459 inode->i_fop = &btrfs_file_operations;
3460 inode->i_op = &btrfs_file_inode_operations;
3463 inode->i_fop = &btrfs_dir_file_operations;
3464 if (root == root->fs_info->tree_root)
3465 inode->i_op = &btrfs_dir_ro_inode_operations;
3467 inode->i_op = &btrfs_dir_inode_operations;
3470 inode->i_op = &btrfs_symlink_inode_operations;
3471 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3472 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3475 inode->i_op = &btrfs_special_inode_operations;
3476 init_special_inode(inode, inode->i_mode, rdev);
3480 btrfs_update_iflags(inode);
3484 btrfs_free_path(path);
3485 make_bad_inode(inode);
3489 * given a leaf and an inode, copy the inode fields into the leaf
3491 static void fill_inode_item(struct btrfs_trans_handle *trans,
3492 struct extent_buffer *leaf,
3493 struct btrfs_inode_item *item,
3494 struct inode *inode)
3496 struct btrfs_map_token token;
3498 btrfs_init_map_token(&token);
3500 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3501 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3502 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3504 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3505 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3507 btrfs_set_token_timespec_sec(leaf, btrfs_inode_atime(item),
3508 inode->i_atime.tv_sec, &token);
3509 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_atime(item),
3510 inode->i_atime.tv_nsec, &token);
3512 btrfs_set_token_timespec_sec(leaf, btrfs_inode_mtime(item),
3513 inode->i_mtime.tv_sec, &token);
3514 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_mtime(item),
3515 inode->i_mtime.tv_nsec, &token);
3517 btrfs_set_token_timespec_sec(leaf, btrfs_inode_ctime(item),
3518 inode->i_ctime.tv_sec, &token);
3519 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_ctime(item),
3520 inode->i_ctime.tv_nsec, &token);
3522 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3524 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3526 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token);
3527 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3528 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3529 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3530 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3534 * copy everything in the in-memory inode into the btree.
3536 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3537 struct btrfs_root *root, struct inode *inode)
3539 struct btrfs_inode_item *inode_item;
3540 struct btrfs_path *path;
3541 struct extent_buffer *leaf;
3544 path = btrfs_alloc_path();
3548 path->leave_spinning = 1;
3549 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3557 leaf = path->nodes[0];
3558 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3559 struct btrfs_inode_item);
3561 fill_inode_item(trans, leaf, inode_item, inode);
3562 btrfs_mark_buffer_dirty(leaf);
3563 btrfs_set_inode_last_trans(trans, inode);
3566 btrfs_free_path(path);
3571 * copy everything in the in-memory inode into the btree.
3573 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3574 struct btrfs_root *root, struct inode *inode)
3579 * If the inode is a free space inode, we can deadlock during commit
3580 * if we put it into the delayed code.
3582 * The data relocation inode should also be directly updated
3585 if (!btrfs_is_free_space_inode(inode)
3586 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
3587 btrfs_update_root_times(trans, root);
3589 ret = btrfs_delayed_update_inode(trans, root, inode);
3591 btrfs_set_inode_last_trans(trans, inode);
3595 return btrfs_update_inode_item(trans, root, inode);
3598 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3599 struct btrfs_root *root,
3600 struct inode *inode)
3604 ret = btrfs_update_inode(trans, root, inode);
3606 return btrfs_update_inode_item(trans, root, inode);
3611 * unlink helper that gets used here in inode.c and in the tree logging
3612 * recovery code. It remove a link in a directory with a given name, and
3613 * also drops the back refs in the inode to the directory
3615 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3616 struct btrfs_root *root,
3617 struct inode *dir, struct inode *inode,
3618 const char *name, int name_len)
3620 struct btrfs_path *path;
3622 struct extent_buffer *leaf;
3623 struct btrfs_dir_item *di;
3624 struct btrfs_key key;
3626 u64 ino = btrfs_ino(inode);
3627 u64 dir_ino = btrfs_ino(dir);
3629 path = btrfs_alloc_path();
3635 path->leave_spinning = 1;
3636 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3637 name, name_len, -1);
3646 leaf = path->nodes[0];
3647 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3648 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3651 btrfs_release_path(path);
3654 * If we don't have dir index, we have to get it by looking up
3655 * the inode ref, since we get the inode ref, remove it directly,
3656 * it is unnecessary to do delayed deletion.
3658 * But if we have dir index, needn't search inode ref to get it.
3659 * Since the inode ref is close to the inode item, it is better
3660 * that we delay to delete it, and just do this deletion when
3661 * we update the inode item.
3663 if (BTRFS_I(inode)->dir_index) {
3664 ret = btrfs_delayed_delete_inode_ref(inode);
3666 index = BTRFS_I(inode)->dir_index;
3671 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3674 btrfs_info(root->fs_info,
3675 "failed to delete reference to %.*s, inode %llu parent %llu",
3676 name_len, name, ino, dir_ino);
3677 btrfs_abort_transaction(trans, root, ret);
3681 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3683 btrfs_abort_transaction(trans, root, ret);
3687 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
3689 if (ret != 0 && ret != -ENOENT) {
3690 btrfs_abort_transaction(trans, root, ret);
3694 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
3699 btrfs_abort_transaction(trans, root, ret);
3701 btrfs_free_path(path);
3705 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3706 inode_inc_iversion(inode);
3707 inode_inc_iversion(dir);
3708 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3709 ret = btrfs_update_inode(trans, root, dir);
3714 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3715 struct btrfs_root *root,
3716 struct inode *dir, struct inode *inode,
3717 const char *name, int name_len)
3720 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3723 ret = btrfs_update_inode(trans, root, inode);
3729 * helper to start transaction for unlink and rmdir.
3731 * unlink and rmdir are special in btrfs, they do not always free space, so
3732 * if we cannot make our reservations the normal way try and see if there is
3733 * plenty of slack room in the global reserve to migrate, otherwise we cannot
3734 * allow the unlink to occur.
3736 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
3738 struct btrfs_trans_handle *trans;
3739 struct btrfs_root *root = BTRFS_I(dir)->root;
3743 * 1 for the possible orphan item
3744 * 1 for the dir item
3745 * 1 for the dir index
3746 * 1 for the inode ref
3749 trans = btrfs_start_transaction(root, 5);
3750 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
3753 if (PTR_ERR(trans) == -ENOSPC) {
3754 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3756 trans = btrfs_start_transaction(root, 0);
3759 ret = btrfs_cond_migrate_bytes(root->fs_info,
3760 &root->fs_info->trans_block_rsv,
3763 btrfs_end_transaction(trans, root);
3764 return ERR_PTR(ret);
3766 trans->block_rsv = &root->fs_info->trans_block_rsv;
3767 trans->bytes_reserved = num_bytes;
3772 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3774 struct btrfs_root *root = BTRFS_I(dir)->root;
3775 struct btrfs_trans_handle *trans;
3776 struct inode *inode = dentry->d_inode;
3779 trans = __unlink_start_trans(dir);
3781 return PTR_ERR(trans);
3783 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3785 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3786 dentry->d_name.name, dentry->d_name.len);
3790 if (inode->i_nlink == 0) {
3791 ret = btrfs_orphan_add(trans, inode);
3797 btrfs_end_transaction(trans, root);
3798 btrfs_btree_balance_dirty(root);
3802 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3803 struct btrfs_root *root,
3804 struct inode *dir, u64 objectid,
3805 const char *name, int name_len)
3807 struct btrfs_path *path;
3808 struct extent_buffer *leaf;
3809 struct btrfs_dir_item *di;
3810 struct btrfs_key key;
3813 u64 dir_ino = btrfs_ino(dir);
3815 path = btrfs_alloc_path();
3819 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3820 name, name_len, -1);
3821 if (IS_ERR_OR_NULL(di)) {
3829 leaf = path->nodes[0];
3830 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3831 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3832 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3834 btrfs_abort_transaction(trans, root, ret);
3837 btrfs_release_path(path);
3839 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3840 objectid, root->root_key.objectid,
3841 dir_ino, &index, name, name_len);
3843 if (ret != -ENOENT) {
3844 btrfs_abort_transaction(trans, root, ret);
3847 di = btrfs_search_dir_index_item(root, path, dir_ino,
3849 if (IS_ERR_OR_NULL(di)) {
3854 btrfs_abort_transaction(trans, root, ret);
3858 leaf = path->nodes[0];
3859 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3860 btrfs_release_path(path);
3863 btrfs_release_path(path);
3865 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3867 btrfs_abort_transaction(trans, root, ret);
3871 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3872 inode_inc_iversion(dir);
3873 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3874 ret = btrfs_update_inode_fallback(trans, root, dir);
3876 btrfs_abort_transaction(trans, root, ret);
3878 btrfs_free_path(path);
3882 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3884 struct inode *inode = dentry->d_inode;
3886 struct btrfs_root *root = BTRFS_I(dir)->root;
3887 struct btrfs_trans_handle *trans;
3889 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
3891 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3894 trans = __unlink_start_trans(dir);
3896 return PTR_ERR(trans);
3898 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3899 err = btrfs_unlink_subvol(trans, root, dir,
3900 BTRFS_I(inode)->location.objectid,
3901 dentry->d_name.name,
3902 dentry->d_name.len);
3906 err = btrfs_orphan_add(trans, inode);
3910 /* now the directory is empty */
3911 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3912 dentry->d_name.name, dentry->d_name.len);
3914 btrfs_i_size_write(inode, 0);
3916 btrfs_end_transaction(trans, root);
3917 btrfs_btree_balance_dirty(root);
3923 * this can truncate away extent items, csum items and directory items.
3924 * It starts at a high offset and removes keys until it can't find
3925 * any higher than new_size
3927 * csum items that cross the new i_size are truncated to the new size
3930 * min_type is the minimum key type to truncate down to. If set to 0, this
3931 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3933 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3934 struct btrfs_root *root,
3935 struct inode *inode,
3936 u64 new_size, u32 min_type)
3938 struct btrfs_path *path;
3939 struct extent_buffer *leaf;
3940 struct btrfs_file_extent_item *fi;
3941 struct btrfs_key key;
3942 struct btrfs_key found_key;
3943 u64 extent_start = 0;
3944 u64 extent_num_bytes = 0;
3945 u64 extent_offset = 0;
3947 u64 last_size = (u64)-1;
3948 u32 found_type = (u8)-1;
3951 int pending_del_nr = 0;
3952 int pending_del_slot = 0;
3953 int extent_type = -1;
3956 u64 ino = btrfs_ino(inode);
3958 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3960 path = btrfs_alloc_path();
3966 * We want to drop from the next block forward in case this new size is
3967 * not block aligned since we will be keeping the last block of the
3968 * extent just the way it is.
3970 if (root->ref_cows || root == root->fs_info->tree_root)
3971 btrfs_drop_extent_cache(inode, ALIGN(new_size,
3972 root->sectorsize), (u64)-1, 0);
3975 * This function is also used to drop the items in the log tree before
3976 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3977 * it is used to drop the loged items. So we shouldn't kill the delayed
3980 if (min_type == 0 && root == BTRFS_I(inode)->root)
3981 btrfs_kill_delayed_inode_items(inode);
3984 key.offset = (u64)-1;
3988 path->leave_spinning = 1;
3989 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3996 /* there are no items in the tree for us to truncate, we're
3999 if (path->slots[0] == 0)
4006 leaf = path->nodes[0];
4007 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4008 found_type = btrfs_key_type(&found_key);
4010 if (found_key.objectid != ino)
4013 if (found_type < min_type)
4016 item_end = found_key.offset;
4017 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4018 fi = btrfs_item_ptr(leaf, path->slots[0],
4019 struct btrfs_file_extent_item);
4020 extent_type = btrfs_file_extent_type(leaf, fi);
4021 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4023 btrfs_file_extent_num_bytes(leaf, fi);
4024 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4025 item_end += btrfs_file_extent_inline_len(leaf,
4030 if (found_type > min_type) {
4033 if (item_end < new_size)
4035 if (found_key.offset >= new_size)
4041 /* FIXME, shrink the extent if the ref count is only 1 */
4042 if (found_type != BTRFS_EXTENT_DATA_KEY)
4046 last_size = found_key.offset;
4048 last_size = new_size;
4050 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4052 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4054 u64 orig_num_bytes =
4055 btrfs_file_extent_num_bytes(leaf, fi);
4056 extent_num_bytes = ALIGN(new_size -
4059 btrfs_set_file_extent_num_bytes(leaf, fi,
4061 num_dec = (orig_num_bytes -
4063 if (root->ref_cows && extent_start != 0)
4064 inode_sub_bytes(inode, num_dec);
4065 btrfs_mark_buffer_dirty(leaf);
4068 btrfs_file_extent_disk_num_bytes(leaf,
4070 extent_offset = found_key.offset -
4071 btrfs_file_extent_offset(leaf, fi);
4073 /* FIXME blocksize != 4096 */
4074 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4075 if (extent_start != 0) {
4078 inode_sub_bytes(inode, num_dec);
4081 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4083 * we can't truncate inline items that have had
4087 btrfs_file_extent_compression(leaf, fi) == 0 &&
4088 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4089 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
4090 u32 size = new_size - found_key.offset;
4092 if (root->ref_cows) {
4093 inode_sub_bytes(inode, item_end + 1 -
4097 btrfs_file_extent_calc_inline_size(size);
4098 btrfs_truncate_item(root, path, size, 1);
4099 } else if (root->ref_cows) {
4100 inode_sub_bytes(inode, item_end + 1 -
4106 if (!pending_del_nr) {
4107 /* no pending yet, add ourselves */
4108 pending_del_slot = path->slots[0];
4110 } else if (pending_del_nr &&
4111 path->slots[0] + 1 == pending_del_slot) {
4112 /* hop on the pending chunk */
4114 pending_del_slot = path->slots[0];
4121 if (found_extent && (root->ref_cows ||
4122 root == root->fs_info->tree_root)) {
4123 btrfs_set_path_blocking(path);
4124 ret = btrfs_free_extent(trans, root, extent_start,
4125 extent_num_bytes, 0,
4126 btrfs_header_owner(leaf),
4127 ino, extent_offset, 0);
4131 if (found_type == BTRFS_INODE_ITEM_KEY)
4134 if (path->slots[0] == 0 ||
4135 path->slots[0] != pending_del_slot) {
4136 if (pending_del_nr) {
4137 ret = btrfs_del_items(trans, root, path,
4141 btrfs_abort_transaction(trans,
4147 btrfs_release_path(path);
4154 if (pending_del_nr) {
4155 ret = btrfs_del_items(trans, root, path, pending_del_slot,
4158 btrfs_abort_transaction(trans, root, ret);
4161 if (last_size != (u64)-1)
4162 btrfs_ordered_update_i_size(inode, last_size, NULL);
4163 btrfs_free_path(path);
4168 * btrfs_truncate_page - read, zero a chunk and write a page
4169 * @inode - inode that we're zeroing
4170 * @from - the offset to start zeroing
4171 * @len - the length to zero, 0 to zero the entire range respective to the
4173 * @front - zero up to the offset instead of from the offset on
4175 * This will find the page for the "from" offset and cow the page and zero the
4176 * part we want to zero. This is used with truncate and hole punching.
4178 int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
4181 struct address_space *mapping = inode->i_mapping;
4182 struct btrfs_root *root = BTRFS_I(inode)->root;
4183 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4184 struct btrfs_ordered_extent *ordered;
4185 struct extent_state *cached_state = NULL;
4187 u32 blocksize = root->sectorsize;
4188 pgoff_t index = from >> PAGE_CACHE_SHIFT;
4189 unsigned offset = from & (PAGE_CACHE_SIZE-1);
4191 gfp_t mask = btrfs_alloc_write_mask(mapping);
4196 if ((offset & (blocksize - 1)) == 0 &&
4197 (!len || ((len & (blocksize - 1)) == 0)))
4199 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
4204 page = find_or_create_page(mapping, index, mask);
4206 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4211 page_start = page_offset(page);
4212 page_end = page_start + PAGE_CACHE_SIZE - 1;
4214 if (!PageUptodate(page)) {
4215 ret = btrfs_readpage(NULL, page);
4217 if (page->mapping != mapping) {
4219 page_cache_release(page);
4222 if (!PageUptodate(page)) {
4227 wait_on_page_writeback(page);
4229 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
4230 set_page_extent_mapped(page);
4232 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4234 unlock_extent_cached(io_tree, page_start, page_end,
4235 &cached_state, GFP_NOFS);
4237 page_cache_release(page);
4238 btrfs_start_ordered_extent(inode, ordered, 1);
4239 btrfs_put_ordered_extent(ordered);
4243 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
4244 EXTENT_DIRTY | EXTENT_DELALLOC |
4245 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4246 0, 0, &cached_state, GFP_NOFS);
4248 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
4251 unlock_extent_cached(io_tree, page_start, page_end,
4252 &cached_state, GFP_NOFS);
4256 if (offset != PAGE_CACHE_SIZE) {
4258 len = PAGE_CACHE_SIZE - offset;
4261 memset(kaddr, 0, offset);
4263 memset(kaddr + offset, 0, len);
4264 flush_dcache_page(page);
4267 ClearPageChecked(page);
4268 set_page_dirty(page);
4269 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
4274 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4276 page_cache_release(page);
4281 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4282 u64 offset, u64 len)
4284 struct btrfs_trans_handle *trans;
4288 * Still need to make sure the inode looks like it's been updated so
4289 * that any holes get logged if we fsync.
4291 if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) {
4292 BTRFS_I(inode)->last_trans = root->fs_info->generation;
4293 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4294 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4299 * 1 - for the one we're dropping
4300 * 1 - for the one we're adding
4301 * 1 - for updating the inode.
4303 trans = btrfs_start_transaction(root, 3);
4305 return PTR_ERR(trans);
4307 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4309 btrfs_abort_transaction(trans, root, ret);
4310 btrfs_end_transaction(trans, root);
4314 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset,
4315 0, 0, len, 0, len, 0, 0, 0);
4317 btrfs_abort_transaction(trans, root, ret);
4319 btrfs_update_inode(trans, root, inode);
4320 btrfs_end_transaction(trans, root);
4325 * This function puts in dummy file extents for the area we're creating a hole
4326 * for. So if we are truncating this file to a larger size we need to insert
4327 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4328 * the range between oldsize and size
4330 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4332 struct btrfs_root *root = BTRFS_I(inode)->root;
4333 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4334 struct extent_map *em = NULL;
4335 struct extent_state *cached_state = NULL;
4336 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4337 u64 hole_start = ALIGN(oldsize, root->sectorsize);
4338 u64 block_end = ALIGN(size, root->sectorsize);
4345 * If our size started in the middle of a page we need to zero out the
4346 * rest of the page before we expand the i_size, otherwise we could
4347 * expose stale data.
4349 err = btrfs_truncate_page(inode, oldsize, 0, 0);
4353 if (size <= hole_start)
4357 struct btrfs_ordered_extent *ordered;
4359 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
4361 ordered = btrfs_lookup_ordered_range(inode, hole_start,
4362 block_end - hole_start);
4365 unlock_extent_cached(io_tree, hole_start, block_end - 1,
4366 &cached_state, GFP_NOFS);
4367 btrfs_start_ordered_extent(inode, ordered, 1);
4368 btrfs_put_ordered_extent(ordered);
4371 cur_offset = hole_start;
4373 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
4374 block_end - cur_offset, 0);
4380 last_byte = min(extent_map_end(em), block_end);
4381 last_byte = ALIGN(last_byte , root->sectorsize);
4382 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
4383 struct extent_map *hole_em;
4384 hole_size = last_byte - cur_offset;
4386 err = maybe_insert_hole(root, inode, cur_offset,
4390 btrfs_drop_extent_cache(inode, cur_offset,
4391 cur_offset + hole_size - 1, 0);
4392 hole_em = alloc_extent_map();
4394 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4395 &BTRFS_I(inode)->runtime_flags);
4398 hole_em->start = cur_offset;
4399 hole_em->len = hole_size;
4400 hole_em->orig_start = cur_offset;
4402 hole_em->block_start = EXTENT_MAP_HOLE;
4403 hole_em->block_len = 0;
4404 hole_em->orig_block_len = 0;
4405 hole_em->ram_bytes = hole_size;
4406 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
4407 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4408 hole_em->generation = root->fs_info->generation;
4411 write_lock(&em_tree->lock);
4412 err = add_extent_mapping(em_tree, hole_em, 1);
4413 write_unlock(&em_tree->lock);
4416 btrfs_drop_extent_cache(inode, cur_offset,
4420 free_extent_map(hole_em);
4423 free_extent_map(em);
4425 cur_offset = last_byte;
4426 if (cur_offset >= block_end)
4429 free_extent_map(em);
4430 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
4435 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
4437 struct btrfs_root *root = BTRFS_I(inode)->root;
4438 struct btrfs_trans_handle *trans;
4439 loff_t oldsize = i_size_read(inode);
4440 loff_t newsize = attr->ia_size;
4441 int mask = attr->ia_valid;
4445 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4446 * special case where we need to update the times despite not having
4447 * these flags set. For all other operations the VFS set these flags
4448 * explicitly if it wants a timestamp update.
4450 if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
4451 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
4453 if (newsize > oldsize) {
4454 truncate_pagecache(inode, newsize);
4455 ret = btrfs_cont_expand(inode, oldsize, newsize);
4459 trans = btrfs_start_transaction(root, 1);
4461 return PTR_ERR(trans);
4463 i_size_write(inode, newsize);
4464 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
4465 ret = btrfs_update_inode(trans, root, inode);
4466 btrfs_end_transaction(trans, root);
4470 * We're truncating a file that used to have good data down to
4471 * zero. Make sure it gets into the ordered flush list so that
4472 * any new writes get down to disk quickly.
4475 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4476 &BTRFS_I(inode)->runtime_flags);
4479 * 1 for the orphan item we're going to add
4480 * 1 for the orphan item deletion.
4482 trans = btrfs_start_transaction(root, 2);
4484 return PTR_ERR(trans);
4487 * We need to do this in case we fail at _any_ point during the
4488 * actual truncate. Once we do the truncate_setsize we could
4489 * invalidate pages which forces any outstanding ordered io to
4490 * be instantly completed which will give us extents that need
4491 * to be truncated. If we fail to get an orphan inode down we
4492 * could have left over extents that were never meant to live,
4493 * so we need to garuntee from this point on that everything
4494 * will be consistent.
4496 ret = btrfs_orphan_add(trans, inode);
4497 btrfs_end_transaction(trans, root);
4501 /* we don't support swapfiles, so vmtruncate shouldn't fail */
4502 truncate_setsize(inode, newsize);
4504 /* Disable nonlocked read DIO to avoid the end less truncate */
4505 btrfs_inode_block_unlocked_dio(inode);
4506 inode_dio_wait(inode);
4507 btrfs_inode_resume_unlocked_dio(inode);
4509 ret = btrfs_truncate(inode);
4510 if (ret && inode->i_nlink) {
4514 * failed to truncate, disk_i_size is only adjusted down
4515 * as we remove extents, so it should represent the true
4516 * size of the inode, so reset the in memory size and
4517 * delete our orphan entry.
4519 trans = btrfs_join_transaction(root);
4520 if (IS_ERR(trans)) {
4521 btrfs_orphan_del(NULL, inode);
4524 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
4525 err = btrfs_orphan_del(trans, inode);
4527 btrfs_abort_transaction(trans, root, err);
4528 btrfs_end_transaction(trans, root);
4535 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4537 struct inode *inode = dentry->d_inode;
4538 struct btrfs_root *root = BTRFS_I(inode)->root;
4541 if (btrfs_root_readonly(root))
4544 err = inode_change_ok(inode, attr);
4548 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
4549 err = btrfs_setsize(inode, attr);
4554 if (attr->ia_valid) {
4555 setattr_copy(inode, attr);
4556 inode_inc_iversion(inode);
4557 err = btrfs_dirty_inode(inode);
4559 if (!err && attr->ia_valid & ATTR_MODE)
4560 err = btrfs_acl_chmod(inode);
4567 * While truncating the inode pages during eviction, we get the VFS calling
4568 * btrfs_invalidatepage() against each page of the inode. This is slow because
4569 * the calls to btrfs_invalidatepage() result in a huge amount of calls to
4570 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting
4571 * extent_state structures over and over, wasting lots of time.
4573 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all
4574 * those expensive operations on a per page basis and do only the ordered io
4575 * finishing, while we release here the extent_map and extent_state structures,
4576 * without the excessive merging and splitting.
4578 static void evict_inode_truncate_pages(struct inode *inode)
4580 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4581 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree;
4582 struct rb_node *node;
4584 ASSERT(inode->i_state & I_FREEING);
4585 truncate_inode_pages(&inode->i_data, 0);
4587 write_lock(&map_tree->lock);
4588 while (!RB_EMPTY_ROOT(&map_tree->map)) {
4589 struct extent_map *em;
4591 node = rb_first(&map_tree->map);
4592 em = rb_entry(node, struct extent_map, rb_node);
4593 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
4594 clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
4595 remove_extent_mapping(map_tree, em);
4596 free_extent_map(em);
4598 write_unlock(&map_tree->lock);
4600 spin_lock(&io_tree->lock);
4601 while (!RB_EMPTY_ROOT(&io_tree->state)) {
4602 struct extent_state *state;
4603 struct extent_state *cached_state = NULL;
4605 node = rb_first(&io_tree->state);
4606 state = rb_entry(node, struct extent_state, rb_node);
4607 atomic_inc(&state->refs);
4608 spin_unlock(&io_tree->lock);
4610 lock_extent_bits(io_tree, state->start, state->end,
4612 clear_extent_bit(io_tree, state->start, state->end,
4613 EXTENT_LOCKED | EXTENT_DIRTY |
4614 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
4615 EXTENT_DEFRAG, 1, 1,
4616 &cached_state, GFP_NOFS);
4617 free_extent_state(state);
4619 spin_lock(&io_tree->lock);
4621 spin_unlock(&io_tree->lock);
4624 void btrfs_evict_inode(struct inode *inode)
4626 struct btrfs_trans_handle *trans;
4627 struct btrfs_root *root = BTRFS_I(inode)->root;
4628 struct btrfs_block_rsv *rsv, *global_rsv;
4629 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
4632 trace_btrfs_inode_evict(inode);
4634 evict_inode_truncate_pages(inode);
4636 if (inode->i_nlink &&
4637 ((btrfs_root_refs(&root->root_item) != 0 &&
4638 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
4639 btrfs_is_free_space_inode(inode)))
4642 if (is_bad_inode(inode)) {
4643 btrfs_orphan_del(NULL, inode);
4646 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
4647 btrfs_wait_ordered_range(inode, 0, (u64)-1);
4649 if (root->fs_info->log_root_recovering) {
4650 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
4651 &BTRFS_I(inode)->runtime_flags));
4655 if (inode->i_nlink > 0) {
4656 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
4657 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
4661 ret = btrfs_commit_inode_delayed_inode(inode);
4663 btrfs_orphan_del(NULL, inode);
4667 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
4669 btrfs_orphan_del(NULL, inode);
4672 rsv->size = min_size;
4674 global_rsv = &root->fs_info->global_block_rsv;
4676 btrfs_i_size_write(inode, 0);
4679 * This is a bit simpler than btrfs_truncate since we've already
4680 * reserved our space for our orphan item in the unlink, so we just
4681 * need to reserve some slack space in case we add bytes and update
4682 * inode item when doing the truncate.
4685 ret = btrfs_block_rsv_refill(root, rsv, min_size,
4686 BTRFS_RESERVE_FLUSH_LIMIT);
4689 * Try and steal from the global reserve since we will
4690 * likely not use this space anyway, we want to try as
4691 * hard as possible to get this to work.
4694 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
4697 btrfs_warn(root->fs_info,
4698 "Could not get space for a delete, will truncate on mount %d",
4700 btrfs_orphan_del(NULL, inode);
4701 btrfs_free_block_rsv(root, rsv);
4705 trans = btrfs_join_transaction(root);
4706 if (IS_ERR(trans)) {
4707 btrfs_orphan_del(NULL, inode);
4708 btrfs_free_block_rsv(root, rsv);
4712 trans->block_rsv = rsv;
4714 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
4718 trans->block_rsv = &root->fs_info->trans_block_rsv;
4719 btrfs_end_transaction(trans, root);
4721 btrfs_btree_balance_dirty(root);
4724 btrfs_free_block_rsv(root, rsv);
4727 * Errors here aren't a big deal, it just means we leave orphan items
4728 * in the tree. They will be cleaned up on the next mount.
4731 trans->block_rsv = root->orphan_block_rsv;
4732 btrfs_orphan_del(trans, inode);
4734 btrfs_orphan_del(NULL, inode);
4737 trans->block_rsv = &root->fs_info->trans_block_rsv;
4738 if (!(root == root->fs_info->tree_root ||
4739 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
4740 btrfs_return_ino(root, btrfs_ino(inode));
4742 btrfs_end_transaction(trans, root);
4743 btrfs_btree_balance_dirty(root);
4745 btrfs_remove_delayed_node(inode);
4751 * this returns the key found in the dir entry in the location pointer.
4752 * If no dir entries were found, location->objectid is 0.
4754 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
4755 struct btrfs_key *location)
4757 const char *name = dentry->d_name.name;
4758 int namelen = dentry->d_name.len;
4759 struct btrfs_dir_item *di;
4760 struct btrfs_path *path;
4761 struct btrfs_root *root = BTRFS_I(dir)->root;
4764 path = btrfs_alloc_path();
4768 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
4773 if (IS_ERR_OR_NULL(di))
4776 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
4778 btrfs_free_path(path);
4781 location->objectid = 0;
4786 * when we hit a tree root in a directory, the btrfs part of the inode
4787 * needs to be changed to reflect the root directory of the tree root. This
4788 * is kind of like crossing a mount point.
4790 static int fixup_tree_root_location(struct btrfs_root *root,
4792 struct dentry *dentry,
4793 struct btrfs_key *location,
4794 struct btrfs_root **sub_root)
4796 struct btrfs_path *path;
4797 struct btrfs_root *new_root;
4798 struct btrfs_root_ref *ref;
4799 struct extent_buffer *leaf;
4803 path = btrfs_alloc_path();
4810 ret = btrfs_find_item(root->fs_info->tree_root, path,
4811 BTRFS_I(dir)->root->root_key.objectid,
4812 location->objectid, BTRFS_ROOT_REF_KEY, NULL);
4819 leaf = path->nodes[0];
4820 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
4821 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
4822 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
4825 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
4826 (unsigned long)(ref + 1),
4827 dentry->d_name.len);
4831 btrfs_release_path(path);
4833 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
4834 if (IS_ERR(new_root)) {
4835 err = PTR_ERR(new_root);
4839 *sub_root = new_root;
4840 location->objectid = btrfs_root_dirid(&new_root->root_item);
4841 location->type = BTRFS_INODE_ITEM_KEY;
4842 location->offset = 0;
4845 btrfs_free_path(path);
4849 static void inode_tree_add(struct inode *inode)
4851 struct btrfs_root *root = BTRFS_I(inode)->root;
4852 struct btrfs_inode *entry;
4854 struct rb_node *parent;
4855 struct rb_node *new = &BTRFS_I(inode)->rb_node;
4856 u64 ino = btrfs_ino(inode);
4858 if (inode_unhashed(inode))
4861 spin_lock(&root->inode_lock);
4862 p = &root->inode_tree.rb_node;
4865 entry = rb_entry(parent, struct btrfs_inode, rb_node);
4867 if (ino < btrfs_ino(&entry->vfs_inode))
4868 p = &parent->rb_left;
4869 else if (ino > btrfs_ino(&entry->vfs_inode))
4870 p = &parent->rb_right;
4872 WARN_ON(!(entry->vfs_inode.i_state &
4873 (I_WILL_FREE | I_FREEING)));
4874 rb_replace_node(parent, new, &root->inode_tree);
4875 RB_CLEAR_NODE(parent);
4876 spin_unlock(&root->inode_lock);
4880 rb_link_node(new, parent, p);
4881 rb_insert_color(new, &root->inode_tree);
4882 spin_unlock(&root->inode_lock);
4885 static void inode_tree_del(struct inode *inode)
4887 struct btrfs_root *root = BTRFS_I(inode)->root;
4890 spin_lock(&root->inode_lock);
4891 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
4892 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4893 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
4894 empty = RB_EMPTY_ROOT(&root->inode_tree);
4896 spin_unlock(&root->inode_lock);
4898 if (empty && btrfs_root_refs(&root->root_item) == 0) {
4899 synchronize_srcu(&root->fs_info->subvol_srcu);
4900 spin_lock(&root->inode_lock);
4901 empty = RB_EMPTY_ROOT(&root->inode_tree);
4902 spin_unlock(&root->inode_lock);
4904 btrfs_add_dead_root(root);
4908 void btrfs_invalidate_inodes(struct btrfs_root *root)
4910 struct rb_node *node;
4911 struct rb_node *prev;
4912 struct btrfs_inode *entry;
4913 struct inode *inode;
4916 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4918 spin_lock(&root->inode_lock);
4920 node = root->inode_tree.rb_node;
4924 entry = rb_entry(node, struct btrfs_inode, rb_node);
4926 if (objectid < btrfs_ino(&entry->vfs_inode))
4927 node = node->rb_left;
4928 else if (objectid > btrfs_ino(&entry->vfs_inode))
4929 node = node->rb_right;
4935 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4936 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
4940 prev = rb_next(prev);
4944 entry = rb_entry(node, struct btrfs_inode, rb_node);
4945 objectid = btrfs_ino(&entry->vfs_inode) + 1;
4946 inode = igrab(&entry->vfs_inode);
4948 spin_unlock(&root->inode_lock);
4949 if (atomic_read(&inode->i_count) > 1)
4950 d_prune_aliases(inode);
4952 * btrfs_drop_inode will have it removed from
4953 * the inode cache when its usage count
4958 spin_lock(&root->inode_lock);
4962 if (cond_resched_lock(&root->inode_lock))
4965 node = rb_next(node);
4967 spin_unlock(&root->inode_lock);
4970 static int btrfs_init_locked_inode(struct inode *inode, void *p)
4972 struct btrfs_iget_args *args = p;
4973 inode->i_ino = args->ino;
4974 BTRFS_I(inode)->root = args->root;
4978 static int btrfs_find_actor(struct inode *inode, void *opaque)
4980 struct btrfs_iget_args *args = opaque;
4981 return args->ino == btrfs_ino(inode) &&
4982 args->root == BTRFS_I(inode)->root;
4985 static struct inode *btrfs_iget_locked(struct super_block *s,
4987 struct btrfs_root *root)
4989 struct inode *inode;
4990 struct btrfs_iget_args args;
4991 unsigned long hashval = btrfs_inode_hash(objectid, root);
4993 args.ino = objectid;
4996 inode = iget5_locked(s, hashval, btrfs_find_actor,
4997 btrfs_init_locked_inode,
5002 /* Get an inode object given its location and corresponding root.
5003 * Returns in *is_new if the inode was read from disk
5005 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
5006 struct btrfs_root *root, int *new)
5008 struct inode *inode;
5010 inode = btrfs_iget_locked(s, location->objectid, root);
5012 return ERR_PTR(-ENOMEM);
5014 if (inode->i_state & I_NEW) {
5015 BTRFS_I(inode)->root = root;
5016 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
5017 btrfs_read_locked_inode(inode);
5018 if (!is_bad_inode(inode)) {
5019 inode_tree_add(inode);
5020 unlock_new_inode(inode);
5024 unlock_new_inode(inode);
5026 inode = ERR_PTR(-ESTALE);
5033 static struct inode *new_simple_dir(struct super_block *s,
5034 struct btrfs_key *key,
5035 struct btrfs_root *root)
5037 struct inode *inode = new_inode(s);
5040 return ERR_PTR(-ENOMEM);
5042 BTRFS_I(inode)->root = root;
5043 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5044 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5046 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5047 inode->i_op = &btrfs_dir_ro_inode_operations;
5048 inode->i_fop = &simple_dir_operations;
5049 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5050 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5055 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5057 struct inode *inode;
5058 struct btrfs_root *root = BTRFS_I(dir)->root;
5059 struct btrfs_root *sub_root = root;
5060 struct btrfs_key location;
5064 if (dentry->d_name.len > BTRFS_NAME_LEN)
5065 return ERR_PTR(-ENAMETOOLONG);
5067 ret = btrfs_inode_by_name(dir, dentry, &location);
5069 return ERR_PTR(ret);
5071 if (location.objectid == 0)
5072 return ERR_PTR(-ENOENT);
5074 if (location.type == BTRFS_INODE_ITEM_KEY) {
5075 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
5079 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
5081 index = srcu_read_lock(&root->fs_info->subvol_srcu);
5082 ret = fixup_tree_root_location(root, dir, dentry,
5083 &location, &sub_root);
5086 inode = ERR_PTR(ret);
5088 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5090 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
5092 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
5094 if (!IS_ERR(inode) && root != sub_root) {
5095 down_read(&root->fs_info->cleanup_work_sem);
5096 if (!(inode->i_sb->s_flags & MS_RDONLY))
5097 ret = btrfs_orphan_cleanup(sub_root);
5098 up_read(&root->fs_info->cleanup_work_sem);
5101 inode = ERR_PTR(ret);
5108 static int btrfs_dentry_delete(const struct dentry *dentry)
5110 struct btrfs_root *root;
5111 struct inode *inode = dentry->d_inode;
5113 if (!inode && !IS_ROOT(dentry))
5114 inode = dentry->d_parent->d_inode;
5117 root = BTRFS_I(inode)->root;
5118 if (btrfs_root_refs(&root->root_item) == 0)
5121 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5127 static void btrfs_dentry_release(struct dentry *dentry)
5129 if (dentry->d_fsdata)
5130 kfree(dentry->d_fsdata);
5133 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5136 struct inode *inode;
5138 inode = btrfs_lookup_dentry(dir, dentry);
5139 if (IS_ERR(inode)) {
5140 if (PTR_ERR(inode) == -ENOENT)
5143 return ERR_CAST(inode);
5146 return d_splice_alias(inode, dentry);
5149 unsigned char btrfs_filetype_table[] = {
5150 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5153 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5155 struct inode *inode = file_inode(file);
5156 struct btrfs_root *root = BTRFS_I(inode)->root;
5157 struct btrfs_item *item;
5158 struct btrfs_dir_item *di;
5159 struct btrfs_key key;
5160 struct btrfs_key found_key;
5161 struct btrfs_path *path;
5162 struct list_head ins_list;
5163 struct list_head del_list;
5165 struct extent_buffer *leaf;
5167 unsigned char d_type;
5172 int key_type = BTRFS_DIR_INDEX_KEY;
5176 int is_curr = 0; /* ctx->pos points to the current index? */
5178 /* FIXME, use a real flag for deciding about the key type */
5179 if (root->fs_info->tree_root == root)
5180 key_type = BTRFS_DIR_ITEM_KEY;
5182 if (!dir_emit_dots(file, ctx))
5185 path = btrfs_alloc_path();
5191 if (key_type == BTRFS_DIR_INDEX_KEY) {
5192 INIT_LIST_HEAD(&ins_list);
5193 INIT_LIST_HEAD(&del_list);
5194 btrfs_get_delayed_items(inode, &ins_list, &del_list);
5197 btrfs_set_key_type(&key, key_type);
5198 key.offset = ctx->pos;
5199 key.objectid = btrfs_ino(inode);
5201 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5206 leaf = path->nodes[0];
5207 slot = path->slots[0];
5208 if (slot >= btrfs_header_nritems(leaf)) {
5209 ret = btrfs_next_leaf(root, path);
5217 item = btrfs_item_nr(slot);
5218 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5220 if (found_key.objectid != key.objectid)
5222 if (btrfs_key_type(&found_key) != key_type)
5224 if (found_key.offset < ctx->pos)
5226 if (key_type == BTRFS_DIR_INDEX_KEY &&
5227 btrfs_should_delete_dir_index(&del_list,
5231 ctx->pos = found_key.offset;
5234 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5236 di_total = btrfs_item_size(leaf, item);
5238 while (di_cur < di_total) {
5239 struct btrfs_key location;
5241 if (verify_dir_item(root, leaf, di))
5244 name_len = btrfs_dir_name_len(leaf, di);
5245 if (name_len <= sizeof(tmp_name)) {
5246 name_ptr = tmp_name;
5248 name_ptr = kmalloc(name_len, GFP_NOFS);
5254 read_extent_buffer(leaf, name_ptr,
5255 (unsigned long)(di + 1), name_len);
5257 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
5258 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5261 /* is this a reference to our own snapshot? If so
5264 * In contrast to old kernels, we insert the snapshot's
5265 * dir item and dir index after it has been created, so
5266 * we won't find a reference to our own snapshot. We
5267 * still keep the following code for backward
5270 if (location.type == BTRFS_ROOT_ITEM_KEY &&
5271 location.objectid == root->root_key.objectid) {
5275 over = !dir_emit(ctx, name_ptr, name_len,
5276 location.objectid, d_type);
5279 if (name_ptr != tmp_name)
5284 di_len = btrfs_dir_name_len(leaf, di) +
5285 btrfs_dir_data_len(leaf, di) + sizeof(*di);
5287 di = (struct btrfs_dir_item *)((char *)di + di_len);
5293 if (key_type == BTRFS_DIR_INDEX_KEY) {
5296 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5301 /* Reached end of directory/root. Bump pos past the last item. */
5305 * Stop new entries from being returned after we return the last
5308 * New directory entries are assigned a strictly increasing
5309 * offset. This means that new entries created during readdir
5310 * are *guaranteed* to be seen in the future by that readdir.
5311 * This has broken buggy programs which operate on names as
5312 * they're returned by readdir. Until we re-use freed offsets
5313 * we have this hack to stop new entries from being returned
5314 * under the assumption that they'll never reach this huge
5317 * This is being careful not to overflow 32bit loff_t unless the
5318 * last entry requires it because doing so has broken 32bit apps
5321 if (key_type == BTRFS_DIR_INDEX_KEY) {
5322 if (ctx->pos >= INT_MAX)
5323 ctx->pos = LLONG_MAX;
5330 if (key_type == BTRFS_DIR_INDEX_KEY)
5331 btrfs_put_delayed_items(&ins_list, &del_list);
5332 btrfs_free_path(path);
5336 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
5338 struct btrfs_root *root = BTRFS_I(inode)->root;
5339 struct btrfs_trans_handle *trans;
5341 bool nolock = false;
5343 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5346 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode))
5349 if (wbc->sync_mode == WB_SYNC_ALL) {
5351 trans = btrfs_join_transaction_nolock(root);
5353 trans = btrfs_join_transaction(root);
5355 return PTR_ERR(trans);
5356 ret = btrfs_commit_transaction(trans, root);
5362 * This is somewhat expensive, updating the tree every time the
5363 * inode changes. But, it is most likely to find the inode in cache.
5364 * FIXME, needs more benchmarking...there are no reasons other than performance
5365 * to keep or drop this code.
5367 static int btrfs_dirty_inode(struct inode *inode)
5369 struct btrfs_root *root = BTRFS_I(inode)->root;
5370 struct btrfs_trans_handle *trans;
5373 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5376 trans = btrfs_join_transaction(root);
5378 return PTR_ERR(trans);
5380 ret = btrfs_update_inode(trans, root, inode);
5381 if (ret && ret == -ENOSPC) {
5382 /* whoops, lets try again with the full transaction */
5383 btrfs_end_transaction(trans, root);
5384 trans = btrfs_start_transaction(root, 1);
5386 return PTR_ERR(trans);
5388 ret = btrfs_update_inode(trans, root, inode);
5390 btrfs_end_transaction(trans, root);
5391 if (BTRFS_I(inode)->delayed_node)
5392 btrfs_balance_delayed_items(root);
5398 * This is a copy of file_update_time. We need this so we can return error on
5399 * ENOSPC for updating the inode in the case of file write and mmap writes.
5401 static int btrfs_update_time(struct inode *inode, struct timespec *now,
5404 struct btrfs_root *root = BTRFS_I(inode)->root;
5406 if (btrfs_root_readonly(root))
5409 if (flags & S_VERSION)
5410 inode_inc_iversion(inode);
5411 if (flags & S_CTIME)
5412 inode->i_ctime = *now;
5413 if (flags & S_MTIME)
5414 inode->i_mtime = *now;
5415 if (flags & S_ATIME)
5416 inode->i_atime = *now;
5417 return btrfs_dirty_inode(inode);
5421 * find the highest existing sequence number in a directory
5422 * and then set the in-memory index_cnt variable to reflect
5423 * free sequence numbers
5425 static int btrfs_set_inode_index_count(struct inode *inode)
5427 struct btrfs_root *root = BTRFS_I(inode)->root;
5428 struct btrfs_key key, found_key;
5429 struct btrfs_path *path;
5430 struct extent_buffer *leaf;
5433 key.objectid = btrfs_ino(inode);
5434 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
5435 key.offset = (u64)-1;
5437 path = btrfs_alloc_path();
5441 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5444 /* FIXME: we should be able to handle this */
5450 * MAGIC NUMBER EXPLANATION:
5451 * since we search a directory based on f_pos we have to start at 2
5452 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5453 * else has to start at 2
5455 if (path->slots[0] == 0) {
5456 BTRFS_I(inode)->index_cnt = 2;
5462 leaf = path->nodes[0];
5463 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5465 if (found_key.objectid != btrfs_ino(inode) ||
5466 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
5467 BTRFS_I(inode)->index_cnt = 2;
5471 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
5473 btrfs_free_path(path);
5478 * helper to find a free sequence number in a given directory. This current
5479 * code is very simple, later versions will do smarter things in the btree
5481 int btrfs_set_inode_index(struct inode *dir, u64 *index)
5485 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
5486 ret = btrfs_inode_delayed_dir_index_count(dir);
5488 ret = btrfs_set_inode_index_count(dir);
5494 *index = BTRFS_I(dir)->index_cnt;
5495 BTRFS_I(dir)->index_cnt++;
5500 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5501 struct btrfs_root *root,
5503 const char *name, int name_len,
5504 u64 ref_objectid, u64 objectid,
5505 umode_t mode, u64 *index)
5507 struct inode *inode;
5508 struct btrfs_inode_item *inode_item;
5509 struct btrfs_key *location;
5510 struct btrfs_path *path;
5511 struct btrfs_inode_ref *ref;
5512 struct btrfs_key key[2];
5517 path = btrfs_alloc_path();
5519 return ERR_PTR(-ENOMEM);
5521 inode = new_inode(root->fs_info->sb);
5523 btrfs_free_path(path);
5524 return ERR_PTR(-ENOMEM);
5528 * we have to initialize this early, so we can reclaim the inode
5529 * number if we fail afterwards in this function.
5531 inode->i_ino = objectid;
5534 trace_btrfs_inode_request(dir);
5536 ret = btrfs_set_inode_index(dir, index);
5538 btrfs_free_path(path);
5540 return ERR_PTR(ret);
5544 * index_cnt is ignored for everything but a dir,
5545 * btrfs_get_inode_index_count has an explanation for the magic
5548 BTRFS_I(inode)->index_cnt = 2;
5549 BTRFS_I(inode)->dir_index = *index;
5550 BTRFS_I(inode)->root = root;
5551 BTRFS_I(inode)->generation = trans->transid;
5552 inode->i_generation = BTRFS_I(inode)->generation;
5555 * We could have gotten an inode number from somebody who was fsynced
5556 * and then removed in this same transaction, so let's just set full
5557 * sync since it will be a full sync anyway and this will blow away the
5558 * old info in the log.
5560 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5562 key[0].objectid = objectid;
5563 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
5567 * Start new inodes with an inode_ref. This is slightly more
5568 * efficient for small numbers of hard links since they will
5569 * be packed into one item. Extended refs will kick in if we
5570 * add more hard links than can fit in the ref item.
5572 key[1].objectid = objectid;
5573 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
5574 key[1].offset = ref_objectid;
5576 sizes[0] = sizeof(struct btrfs_inode_item);
5577 sizes[1] = name_len + sizeof(*ref);
5579 path->leave_spinning = 1;
5580 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
5584 inode_init_owner(inode, dir, mode);
5585 inode_set_bytes(inode, 0);
5586 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5587 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
5588 struct btrfs_inode_item);
5589 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
5590 sizeof(*inode_item));
5591 fill_inode_item(trans, path->nodes[0], inode_item, inode);
5593 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
5594 struct btrfs_inode_ref);
5595 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
5596 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
5597 ptr = (unsigned long)(ref + 1);
5598 write_extent_buffer(path->nodes[0], name, ptr, name_len);
5600 btrfs_mark_buffer_dirty(path->nodes[0]);
5601 btrfs_free_path(path);
5603 location = &BTRFS_I(inode)->location;
5604 location->objectid = objectid;
5605 location->offset = 0;
5606 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
5608 btrfs_inherit_iflags(inode, dir);
5610 if (S_ISREG(mode)) {
5611 if (btrfs_test_opt(root, NODATASUM))
5612 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
5613 if (btrfs_test_opt(root, NODATACOW))
5614 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
5615 BTRFS_INODE_NODATASUM;
5618 btrfs_insert_inode_hash(inode);
5619 inode_tree_add(inode);
5621 trace_btrfs_inode_new(inode);
5622 btrfs_set_inode_last_trans(trans, inode);
5624 btrfs_update_root_times(trans, root);
5626 ret = btrfs_inode_inherit_props(trans, inode, dir);
5628 btrfs_err(root->fs_info,
5629 "error inheriting props for ino %llu (root %llu): %d",
5630 btrfs_ino(inode), root->root_key.objectid, ret);
5635 BTRFS_I(dir)->index_cnt--;
5636 btrfs_free_path(path);
5638 return ERR_PTR(ret);
5641 static inline u8 btrfs_inode_type(struct inode *inode)
5643 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
5647 * utility function to add 'inode' into 'parent_inode' with
5648 * a give name and a given sequence number.
5649 * if 'add_backref' is true, also insert a backref from the
5650 * inode to the parent directory.
5652 int btrfs_add_link(struct btrfs_trans_handle *trans,
5653 struct inode *parent_inode, struct inode *inode,
5654 const char *name, int name_len, int add_backref, u64 index)
5657 struct btrfs_key key;
5658 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
5659 u64 ino = btrfs_ino(inode);
5660 u64 parent_ino = btrfs_ino(parent_inode);
5662 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5663 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
5666 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
5670 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5671 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
5672 key.objectid, root->root_key.objectid,
5673 parent_ino, index, name, name_len);
5674 } else if (add_backref) {
5675 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
5679 /* Nothing to clean up yet */
5683 ret = btrfs_insert_dir_item(trans, root, name, name_len,
5685 btrfs_inode_type(inode), index);
5686 if (ret == -EEXIST || ret == -EOVERFLOW)
5689 btrfs_abort_transaction(trans, root, ret);
5693 btrfs_i_size_write(parent_inode, parent_inode->i_size +
5695 inode_inc_iversion(parent_inode);
5696 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
5697 ret = btrfs_update_inode(trans, root, parent_inode);
5699 btrfs_abort_transaction(trans, root, ret);
5703 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5706 err = btrfs_del_root_ref(trans, root->fs_info->tree_root,
5707 key.objectid, root->root_key.objectid,
5708 parent_ino, &local_index, name, name_len);
5710 } else if (add_backref) {
5714 err = btrfs_del_inode_ref(trans, root, name, name_len,
5715 ino, parent_ino, &local_index);
5720 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
5721 struct inode *dir, struct dentry *dentry,
5722 struct inode *inode, int backref, u64 index)
5724 int err = btrfs_add_link(trans, dir, inode,
5725 dentry->d_name.name, dentry->d_name.len,
5732 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
5733 umode_t mode, dev_t rdev)
5735 struct btrfs_trans_handle *trans;
5736 struct btrfs_root *root = BTRFS_I(dir)->root;
5737 struct inode *inode = NULL;
5743 if (!new_valid_dev(rdev))
5747 * 2 for inode item and ref
5749 * 1 for xattr if selinux is on
5751 trans = btrfs_start_transaction(root, 5);
5753 return PTR_ERR(trans);
5755 err = btrfs_find_free_ino(root, &objectid);
5759 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5760 dentry->d_name.len, btrfs_ino(dir), objectid,
5762 if (IS_ERR(inode)) {
5763 err = PTR_ERR(inode);
5767 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5774 * If the active LSM wants to access the inode during
5775 * d_instantiate it needs these. Smack checks to see
5776 * if the filesystem supports xattrs by looking at the
5780 inode->i_op = &btrfs_special_inode_operations;
5781 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5785 init_special_inode(inode, inode->i_mode, rdev);
5786 btrfs_update_inode(trans, root, inode);
5787 d_instantiate(dentry, inode);
5790 btrfs_end_transaction(trans, root);
5791 btrfs_btree_balance_dirty(root);
5793 inode_dec_link_count(inode);
5799 static int btrfs_create(struct inode *dir, struct dentry *dentry,
5800 umode_t mode, bool excl)
5802 struct btrfs_trans_handle *trans;
5803 struct btrfs_root *root = BTRFS_I(dir)->root;
5804 struct inode *inode = NULL;
5805 int drop_inode_on_err = 0;
5811 * 2 for inode item and ref
5813 * 1 for xattr if selinux is on
5815 trans = btrfs_start_transaction(root, 5);
5817 return PTR_ERR(trans);
5819 err = btrfs_find_free_ino(root, &objectid);
5823 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5824 dentry->d_name.len, btrfs_ino(dir), objectid,
5826 if (IS_ERR(inode)) {
5827 err = PTR_ERR(inode);
5830 drop_inode_on_err = 1;
5832 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5836 err = btrfs_update_inode(trans, root, inode);
5841 * If the active LSM wants to access the inode during
5842 * d_instantiate it needs these. Smack checks to see
5843 * if the filesystem supports xattrs by looking at the
5846 inode->i_fop = &btrfs_file_operations;
5847 inode->i_op = &btrfs_file_inode_operations;
5849 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5853 inode->i_mapping->a_ops = &btrfs_aops;
5854 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5855 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5856 d_instantiate(dentry, inode);
5859 btrfs_end_transaction(trans, root);
5860 if (err && drop_inode_on_err) {
5861 inode_dec_link_count(inode);
5864 btrfs_btree_balance_dirty(root);
5868 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
5869 struct dentry *dentry)
5871 struct btrfs_trans_handle *trans;
5872 struct btrfs_root *root = BTRFS_I(dir)->root;
5873 struct inode *inode = old_dentry->d_inode;
5878 /* do not allow sys_link's with other subvols of the same device */
5879 if (root->objectid != BTRFS_I(inode)->root->objectid)
5882 if (inode->i_nlink >= BTRFS_LINK_MAX)
5885 err = btrfs_set_inode_index(dir, &index);
5890 * 2 items for inode and inode ref
5891 * 2 items for dir items
5892 * 1 item for parent inode
5894 trans = btrfs_start_transaction(root, 5);
5895 if (IS_ERR(trans)) {
5896 err = PTR_ERR(trans);
5900 /* There are several dir indexes for this inode, clear the cache. */
5901 BTRFS_I(inode)->dir_index = 0ULL;
5903 inode_inc_iversion(inode);
5904 inode->i_ctime = CURRENT_TIME;
5906 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
5908 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
5913 struct dentry *parent = dentry->d_parent;
5914 err = btrfs_update_inode(trans, root, inode);
5917 d_instantiate(dentry, inode);
5918 btrfs_log_new_name(trans, inode, NULL, parent);
5921 btrfs_end_transaction(trans, root);
5924 inode_dec_link_count(inode);
5927 btrfs_btree_balance_dirty(root);
5931 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
5933 struct inode *inode = NULL;
5934 struct btrfs_trans_handle *trans;
5935 struct btrfs_root *root = BTRFS_I(dir)->root;
5937 int drop_on_err = 0;
5942 * 2 items for inode and ref
5943 * 2 items for dir items
5944 * 1 for xattr if selinux is on
5946 trans = btrfs_start_transaction(root, 5);
5948 return PTR_ERR(trans);
5950 err = btrfs_find_free_ino(root, &objectid);
5954 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5955 dentry->d_name.len, btrfs_ino(dir), objectid,
5956 S_IFDIR | mode, &index);
5957 if (IS_ERR(inode)) {
5958 err = PTR_ERR(inode);
5964 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5968 inode->i_op = &btrfs_dir_inode_operations;
5969 inode->i_fop = &btrfs_dir_file_operations;
5971 btrfs_i_size_write(inode, 0);
5972 err = btrfs_update_inode(trans, root, inode);
5976 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
5977 dentry->d_name.len, 0, index);
5981 d_instantiate(dentry, inode);
5985 btrfs_end_transaction(trans, root);
5988 btrfs_btree_balance_dirty(root);
5992 /* helper for btfs_get_extent. Given an existing extent in the tree,
5993 * and an extent that you want to insert, deal with overlap and insert
5994 * the new extent into the tree.
5996 static int merge_extent_mapping(struct extent_map_tree *em_tree,
5997 struct extent_map *existing,
5998 struct extent_map *em,
5999 u64 map_start, u64 map_len)
6003 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
6004 start_diff = map_start - em->start;
6005 em->start = map_start;
6007 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
6008 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
6009 em->block_start += start_diff;
6010 em->block_len -= start_diff;
6012 return add_extent_mapping(em_tree, em, 0);
6015 static noinline int uncompress_inline(struct btrfs_path *path,
6016 struct inode *inode, struct page *page,
6017 size_t pg_offset, u64 extent_offset,
6018 struct btrfs_file_extent_item *item)
6021 struct extent_buffer *leaf = path->nodes[0];
6024 unsigned long inline_size;
6028 WARN_ON(pg_offset != 0);
6029 compress_type = btrfs_file_extent_compression(leaf, item);
6030 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6031 inline_size = btrfs_file_extent_inline_item_len(leaf,
6032 btrfs_item_nr(path->slots[0]));
6033 tmp = kmalloc(inline_size, GFP_NOFS);
6036 ptr = btrfs_file_extent_inline_start(item);
6038 read_extent_buffer(leaf, tmp, ptr, inline_size);
6040 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
6041 ret = btrfs_decompress(compress_type, tmp, page,
6042 extent_offset, inline_size, max_size);
6044 char *kaddr = kmap_atomic(page);
6045 unsigned long copy_size = min_t(u64,
6046 PAGE_CACHE_SIZE - pg_offset,
6047 max_size - extent_offset);
6048 memset(kaddr + pg_offset, 0, copy_size);
6049 kunmap_atomic(kaddr);
6056 * a bit scary, this does extent mapping from logical file offset to the disk.
6057 * the ugly parts come from merging extents from the disk with the in-ram
6058 * representation. This gets more complex because of the data=ordered code,
6059 * where the in-ram extents might be locked pending data=ordered completion.
6061 * This also copies inline extents directly into the page.
6064 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
6065 size_t pg_offset, u64 start, u64 len,
6071 u64 extent_start = 0;
6073 u64 objectid = btrfs_ino(inode);
6075 struct btrfs_path *path = NULL;
6076 struct btrfs_root *root = BTRFS_I(inode)->root;
6077 struct btrfs_file_extent_item *item;
6078 struct extent_buffer *leaf;
6079 struct btrfs_key found_key;
6080 struct extent_map *em = NULL;
6081 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
6082 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6083 struct btrfs_trans_handle *trans = NULL;
6087 read_lock(&em_tree->lock);
6088 em = lookup_extent_mapping(em_tree, start, len);
6090 em->bdev = root->fs_info->fs_devices->latest_bdev;
6091 read_unlock(&em_tree->lock);
6094 if (em->start > start || em->start + em->len <= start)
6095 free_extent_map(em);
6096 else if (em->block_start == EXTENT_MAP_INLINE && page)
6097 free_extent_map(em);
6101 em = alloc_extent_map();
6106 em->bdev = root->fs_info->fs_devices->latest_bdev;
6107 em->start = EXTENT_MAP_HOLE;
6108 em->orig_start = EXTENT_MAP_HOLE;
6110 em->block_len = (u64)-1;
6113 path = btrfs_alloc_path();
6119 * Chances are we'll be called again, so go ahead and do
6125 ret = btrfs_lookup_file_extent(trans, root, path,
6126 objectid, start, trans != NULL);
6133 if (path->slots[0] == 0)
6138 leaf = path->nodes[0];
6139 item = btrfs_item_ptr(leaf, path->slots[0],
6140 struct btrfs_file_extent_item);
6141 /* are we inside the extent that was found? */
6142 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6143 found_type = btrfs_key_type(&found_key);
6144 if (found_key.objectid != objectid ||
6145 found_type != BTRFS_EXTENT_DATA_KEY) {
6147 * If we backup past the first extent we want to move forward
6148 * and see if there is an extent in front of us, otherwise we'll
6149 * say there is a hole for our whole search range which can
6156 found_type = btrfs_file_extent_type(leaf, item);
6157 extent_start = found_key.offset;
6158 compress_type = btrfs_file_extent_compression(leaf, item);
6159 if (found_type == BTRFS_FILE_EXTENT_REG ||
6160 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6161 extent_end = extent_start +
6162 btrfs_file_extent_num_bytes(leaf, item);
6163 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6165 size = btrfs_file_extent_inline_len(leaf, item);
6166 extent_end = ALIGN(extent_start + size, root->sectorsize);
6169 if (start >= extent_end) {
6171 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6172 ret = btrfs_next_leaf(root, path);
6179 leaf = path->nodes[0];
6181 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6182 if (found_key.objectid != objectid ||
6183 found_key.type != BTRFS_EXTENT_DATA_KEY)
6185 if (start + len <= found_key.offset)
6188 em->orig_start = start;
6189 em->len = found_key.offset - start;
6193 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, item);
6194 if (found_type == BTRFS_FILE_EXTENT_REG ||
6195 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6196 em->start = extent_start;
6197 em->len = extent_end - extent_start;
6198 em->orig_start = extent_start -
6199 btrfs_file_extent_offset(leaf, item);
6200 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
6202 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
6204 em->block_start = EXTENT_MAP_HOLE;
6207 if (compress_type != BTRFS_COMPRESS_NONE) {
6208 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6209 em->compress_type = compress_type;
6210 em->block_start = bytenr;
6211 em->block_len = em->orig_block_len;
6213 bytenr += btrfs_file_extent_offset(leaf, item);
6214 em->block_start = bytenr;
6215 em->block_len = em->len;
6216 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
6217 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6220 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6224 size_t extent_offset;
6227 em->block_start = EXTENT_MAP_INLINE;
6228 if (!page || create) {
6229 em->start = extent_start;
6230 em->len = extent_end - extent_start;
6234 size = btrfs_file_extent_inline_len(leaf, item);
6235 extent_offset = page_offset(page) + pg_offset - extent_start;
6236 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
6237 size - extent_offset);
6238 em->start = extent_start + extent_offset;
6239 em->len = ALIGN(copy_size, root->sectorsize);
6240 em->orig_block_len = em->len;
6241 em->orig_start = em->start;
6242 if (compress_type) {
6243 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6244 em->compress_type = compress_type;
6246 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6247 if (create == 0 && !PageUptodate(page)) {
6248 if (btrfs_file_extent_compression(leaf, item) !=
6249 BTRFS_COMPRESS_NONE) {
6250 ret = uncompress_inline(path, inode, page,
6252 extent_offset, item);
6253 BUG_ON(ret); /* -ENOMEM */
6256 read_extent_buffer(leaf, map + pg_offset, ptr,
6258 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
6259 memset(map + pg_offset + copy_size, 0,
6260 PAGE_CACHE_SIZE - pg_offset -
6265 flush_dcache_page(page);
6266 } else if (create && PageUptodate(page)) {
6270 free_extent_map(em);
6273 btrfs_release_path(path);
6274 trans = btrfs_join_transaction(root);
6277 return ERR_CAST(trans);
6281 write_extent_buffer(leaf, map + pg_offset, ptr,
6284 btrfs_mark_buffer_dirty(leaf);
6286 set_extent_uptodate(io_tree, em->start,
6287 extent_map_end(em) - 1, NULL, GFP_NOFS);
6290 WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
6294 em->orig_start = start;
6297 em->block_start = EXTENT_MAP_HOLE;
6298 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
6300 btrfs_release_path(path);
6301 if (em->start > start || extent_map_end(em) <= start) {
6302 btrfs_err(root->fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]",
6303 em->start, em->len, start, len);
6309 write_lock(&em_tree->lock);
6310 ret = add_extent_mapping(em_tree, em, 0);
6311 /* it is possible that someone inserted the extent into the tree
6312 * while we had the lock dropped. It is also possible that
6313 * an overlapping map exists in the tree
6315 if (ret == -EEXIST) {
6316 struct extent_map *existing;
6320 existing = lookup_extent_mapping(em_tree, start, len);
6321 if (existing && (existing->start > start ||
6322 existing->start + existing->len <= start)) {
6323 free_extent_map(existing);
6327 existing = lookup_extent_mapping(em_tree, em->start,
6330 err = merge_extent_mapping(em_tree, existing,
6333 free_extent_map(existing);
6335 free_extent_map(em);
6340 free_extent_map(em);
6344 free_extent_map(em);
6349 write_unlock(&em_tree->lock);
6352 trace_btrfs_get_extent(root, em);
6355 btrfs_free_path(path);
6357 ret = btrfs_end_transaction(trans, root);
6362 free_extent_map(em);
6363 return ERR_PTR(err);
6365 BUG_ON(!em); /* Error is always set */
6369 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
6370 size_t pg_offset, u64 start, u64 len,
6373 struct extent_map *em;
6374 struct extent_map *hole_em = NULL;
6375 u64 range_start = start;
6381 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6388 * - a pre-alloc extent,
6389 * there might actually be delalloc bytes behind it.
6391 if (em->block_start != EXTENT_MAP_HOLE &&
6392 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6398 /* check to see if we've wrapped (len == -1 or similar) */
6407 /* ok, we didn't find anything, lets look for delalloc */
6408 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
6409 end, len, EXTENT_DELALLOC, 1);
6410 found_end = range_start + found;
6411 if (found_end < range_start)
6412 found_end = (u64)-1;
6415 * we didn't find anything useful, return
6416 * the original results from get_extent()
6418 if (range_start > end || found_end <= start) {
6424 /* adjust the range_start to make sure it doesn't
6425 * go backwards from the start they passed in
6427 range_start = max(start, range_start);
6428 found = found_end - range_start;
6431 u64 hole_start = start;
6434 em = alloc_extent_map();
6440 * when btrfs_get_extent can't find anything it
6441 * returns one huge hole
6443 * make sure what it found really fits our range, and
6444 * adjust to make sure it is based on the start from
6448 u64 calc_end = extent_map_end(hole_em);
6450 if (calc_end <= start || (hole_em->start > end)) {
6451 free_extent_map(hole_em);
6454 hole_start = max(hole_em->start, start);
6455 hole_len = calc_end - hole_start;
6459 if (hole_em && range_start > hole_start) {
6460 /* our hole starts before our delalloc, so we
6461 * have to return just the parts of the hole
6462 * that go until the delalloc starts
6464 em->len = min(hole_len,
6465 range_start - hole_start);
6466 em->start = hole_start;
6467 em->orig_start = hole_start;
6469 * don't adjust block start at all,
6470 * it is fixed at EXTENT_MAP_HOLE
6472 em->block_start = hole_em->block_start;
6473 em->block_len = hole_len;
6474 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6475 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6477 em->start = range_start;
6479 em->orig_start = range_start;
6480 em->block_start = EXTENT_MAP_DELALLOC;
6481 em->block_len = found;
6483 } else if (hole_em) {
6488 free_extent_map(hole_em);
6490 free_extent_map(em);
6491 return ERR_PTR(err);
6496 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6499 struct btrfs_root *root = BTRFS_I(inode)->root;
6500 struct extent_map *em;
6501 struct btrfs_key ins;
6505 alloc_hint = get_extent_allocation_hint(inode, start, len);
6506 ret = btrfs_reserve_extent(root, len, root->sectorsize, 0,
6507 alloc_hint, &ins, 1);
6509 return ERR_PTR(ret);
6511 em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
6512 ins.offset, ins.offset, ins.offset, 0);
6514 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6518 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
6519 ins.offset, ins.offset, 0);
6521 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6522 free_extent_map(em);
6523 return ERR_PTR(ret);
6530 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6531 * block must be cow'd
6533 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
6534 u64 *orig_start, u64 *orig_block_len,
6537 struct btrfs_trans_handle *trans;
6538 struct btrfs_path *path;
6540 struct extent_buffer *leaf;
6541 struct btrfs_root *root = BTRFS_I(inode)->root;
6542 struct btrfs_file_extent_item *fi;
6543 struct btrfs_key key;
6550 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
6552 path = btrfs_alloc_path();
6556 ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(inode),
6561 slot = path->slots[0];
6564 /* can't find the item, must cow */
6571 leaf = path->nodes[0];
6572 btrfs_item_key_to_cpu(leaf, &key, slot);
6573 if (key.objectid != btrfs_ino(inode) ||
6574 key.type != BTRFS_EXTENT_DATA_KEY) {
6575 /* not our file or wrong item type, must cow */
6579 if (key.offset > offset) {
6580 /* Wrong offset, must cow */
6584 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6585 found_type = btrfs_file_extent_type(leaf, fi);
6586 if (found_type != BTRFS_FILE_EXTENT_REG &&
6587 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6588 /* not a regular extent, must cow */
6592 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
6595 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6596 if (extent_end <= offset)
6599 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6600 if (disk_bytenr == 0)
6603 if (btrfs_file_extent_compression(leaf, fi) ||
6604 btrfs_file_extent_encryption(leaf, fi) ||
6605 btrfs_file_extent_other_encoding(leaf, fi))
6608 backref_offset = btrfs_file_extent_offset(leaf, fi);
6611 *orig_start = key.offset - backref_offset;
6612 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
6613 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6616 if (btrfs_extent_readonly(root, disk_bytenr))
6618 btrfs_release_path(path);
6621 * look for other files referencing this extent, if we
6622 * find any we must cow
6624 trans = btrfs_join_transaction(root);
6625 if (IS_ERR(trans)) {
6630 ret = btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
6631 key.offset - backref_offset, disk_bytenr);
6632 btrfs_end_transaction(trans, root);
6639 * adjust disk_bytenr and num_bytes to cover just the bytes
6640 * in this extent we are about to write. If there
6641 * are any csums in that range we have to cow in order
6642 * to keep the csums correct
6644 disk_bytenr += backref_offset;
6645 disk_bytenr += offset - key.offset;
6646 num_bytes = min(offset + *len, extent_end) - offset;
6647 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
6650 * all of the above have passed, it is safe to overwrite this extent
6656 btrfs_free_path(path);
6660 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
6661 struct extent_state **cached_state, int writing)
6663 struct btrfs_ordered_extent *ordered;
6667 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6670 * We're concerned with the entire range that we're going to be
6671 * doing DIO to, so we need to make sure theres no ordered
6672 * extents in this range.
6674 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6675 lockend - lockstart + 1);
6678 * We need to make sure there are no buffered pages in this
6679 * range either, we could have raced between the invalidate in
6680 * generic_file_direct_write and locking the extent. The
6681 * invalidate needs to happen so that reads after a write do not
6684 if (!ordered && (!writing ||
6685 !test_range_bit(&BTRFS_I(inode)->io_tree,
6686 lockstart, lockend, EXTENT_UPTODATE, 0,
6690 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6691 cached_state, GFP_NOFS);
6694 btrfs_start_ordered_extent(inode, ordered, 1);
6695 btrfs_put_ordered_extent(ordered);
6697 /* Screw you mmap */
6698 ret = filemap_write_and_wait_range(inode->i_mapping,
6705 * If we found a page that couldn't be invalidated just
6706 * fall back to buffered.
6708 ret = invalidate_inode_pages2_range(inode->i_mapping,
6709 lockstart >> PAGE_CACHE_SHIFT,
6710 lockend >> PAGE_CACHE_SHIFT);
6721 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
6722 u64 len, u64 orig_start,
6723 u64 block_start, u64 block_len,
6724 u64 orig_block_len, u64 ram_bytes,
6727 struct extent_map_tree *em_tree;
6728 struct extent_map *em;
6729 struct btrfs_root *root = BTRFS_I(inode)->root;
6732 em_tree = &BTRFS_I(inode)->extent_tree;
6733 em = alloc_extent_map();
6735 return ERR_PTR(-ENOMEM);
6738 em->orig_start = orig_start;
6739 em->mod_start = start;
6742 em->block_len = block_len;
6743 em->block_start = block_start;
6744 em->bdev = root->fs_info->fs_devices->latest_bdev;
6745 em->orig_block_len = orig_block_len;
6746 em->ram_bytes = ram_bytes;
6747 em->generation = -1;
6748 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6749 if (type == BTRFS_ORDERED_PREALLOC)
6750 set_bit(EXTENT_FLAG_FILLING, &em->flags);
6753 btrfs_drop_extent_cache(inode, em->start,
6754 em->start + em->len - 1, 0);
6755 write_lock(&em_tree->lock);
6756 ret = add_extent_mapping(em_tree, em, 1);
6757 write_unlock(&em_tree->lock);
6758 } while (ret == -EEXIST);
6761 free_extent_map(em);
6762 return ERR_PTR(ret);
6769 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
6770 struct buffer_head *bh_result, int create)
6772 struct extent_map *em;
6773 struct btrfs_root *root = BTRFS_I(inode)->root;
6774 struct extent_state *cached_state = NULL;
6775 u64 start = iblock << inode->i_blkbits;
6776 u64 lockstart, lockend;
6777 u64 len = bh_result->b_size;
6778 int unlock_bits = EXTENT_LOCKED;
6782 unlock_bits |= EXTENT_DELALLOC | EXTENT_DIRTY;
6784 len = min_t(u64, len, root->sectorsize);
6787 lockend = start + len - 1;
6790 * If this errors out it's because we couldn't invalidate pagecache for
6791 * this range and we need to fallback to buffered.
6793 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create))
6796 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
6803 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
6804 * io. INLINE is special, and we could probably kludge it in here, but
6805 * it's still buffered so for safety lets just fall back to the generic
6808 * For COMPRESSED we _have_ to read the entire extent in so we can
6809 * decompress it, so there will be buffering required no matter what we
6810 * do, so go ahead and fallback to buffered.
6812 * We return -ENOTBLK because thats what makes DIO go ahead and go back
6813 * to buffered IO. Don't blame me, this is the price we pay for using
6816 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
6817 em->block_start == EXTENT_MAP_INLINE) {
6818 free_extent_map(em);
6823 /* Just a good old fashioned hole, return */
6824 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
6825 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
6826 free_extent_map(em);
6831 * We don't allocate a new extent in the following cases
6833 * 1) The inode is marked as NODATACOW. In this case we'll just use the
6835 * 2) The extent is marked as PREALLOC. We're good to go here and can
6836 * just use the extent.
6840 len = min(len, em->len - (start - em->start));
6841 lockstart = start + len;
6845 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
6846 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
6847 em->block_start != EXTENT_MAP_HOLE)) {
6850 u64 block_start, orig_start, orig_block_len, ram_bytes;
6852 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6853 type = BTRFS_ORDERED_PREALLOC;
6855 type = BTRFS_ORDERED_NOCOW;
6856 len = min(len, em->len - (start - em->start));
6857 block_start = em->block_start + (start - em->start);
6859 if (can_nocow_extent(inode, start, &len, &orig_start,
6860 &orig_block_len, &ram_bytes) == 1) {
6861 if (type == BTRFS_ORDERED_PREALLOC) {
6862 free_extent_map(em);
6863 em = create_pinned_em(inode, start, len,
6872 ret = btrfs_add_ordered_extent_dio(inode, start,
6873 block_start, len, len, type);
6875 free_extent_map(em);
6883 * this will cow the extent, reset the len in case we changed
6886 len = bh_result->b_size;
6887 free_extent_map(em);
6888 em = btrfs_new_extent_direct(inode, start, len);
6893 len = min(len, em->len - (start - em->start));
6895 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
6897 bh_result->b_size = len;
6898 bh_result->b_bdev = em->bdev;
6899 set_buffer_mapped(bh_result);
6901 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6902 set_buffer_new(bh_result);
6905 * Need to update the i_size under the extent lock so buffered
6906 * readers will get the updated i_size when we unlock.
6908 if (start + len > i_size_read(inode))
6909 i_size_write(inode, start + len);
6911 spin_lock(&BTRFS_I(inode)->lock);
6912 BTRFS_I(inode)->outstanding_extents++;
6913 spin_unlock(&BTRFS_I(inode)->lock);
6915 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6916 lockstart + len - 1, EXTENT_DELALLOC, NULL,
6917 &cached_state, GFP_NOFS);
6922 * In the case of write we need to clear and unlock the entire range,
6923 * in the case of read we need to unlock only the end area that we
6924 * aren't using if there is any left over space.
6926 if (lockstart < lockend) {
6927 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6928 lockend, unlock_bits, 1, 0,
6929 &cached_state, GFP_NOFS);
6931 free_extent_state(cached_state);
6934 free_extent_map(em);
6939 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6940 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
6944 static void btrfs_endio_direct_read(struct bio *bio, int err)
6946 struct btrfs_dio_private *dip = bio->bi_private;
6947 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
6948 struct bio_vec *bvec = bio->bi_io_vec;
6949 struct inode *inode = dip->inode;
6950 struct btrfs_root *root = BTRFS_I(inode)->root;
6951 struct bio *dio_bio;
6952 u32 *csums = (u32 *)dip->csum;
6956 start = dip->logical_offset;
6958 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
6959 struct page *page = bvec->bv_page;
6962 unsigned long flags;
6964 local_irq_save(flags);
6965 kaddr = kmap_atomic(page);
6966 csum = btrfs_csum_data(kaddr + bvec->bv_offset,
6967 csum, bvec->bv_len);
6968 btrfs_csum_final(csum, (char *)&csum);
6969 kunmap_atomic(kaddr);
6970 local_irq_restore(flags);
6972 flush_dcache_page(bvec->bv_page);
6973 if (csum != csums[index]) {
6974 btrfs_err(root->fs_info, "csum failed ino %llu off %llu csum %u expected csum %u",
6975 btrfs_ino(inode), start, csum,
6981 start += bvec->bv_len;
6984 } while (bvec <= bvec_end);
6986 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
6987 dip->logical_offset + dip->bytes - 1);
6988 dio_bio = dip->dio_bio;
6992 /* If we had a csum failure make sure to clear the uptodate flag */
6994 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
6995 dio_end_io(dio_bio, err);
6999 static void btrfs_endio_direct_write(struct bio *bio, int err)
7001 struct btrfs_dio_private *dip = bio->bi_private;
7002 struct inode *inode = dip->inode;
7003 struct btrfs_root *root = BTRFS_I(inode)->root;
7004 struct btrfs_ordered_extent *ordered = NULL;
7005 u64 ordered_offset = dip->logical_offset;
7006 u64 ordered_bytes = dip->bytes;
7007 struct bio *dio_bio;
7013 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
7015 ordered_bytes, !err);
7019 ordered->work.func = finish_ordered_fn;
7020 ordered->work.flags = 0;
7021 btrfs_queue_worker(&root->fs_info->endio_write_workers,
7025 * our bio might span multiple ordered extents. If we haven't
7026 * completed the accounting for the whole dio, go back and try again
7028 if (ordered_offset < dip->logical_offset + dip->bytes) {
7029 ordered_bytes = dip->logical_offset + dip->bytes -
7035 dio_bio = dip->dio_bio;
7039 /* If we had an error make sure to clear the uptodate flag */
7041 clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
7042 dio_end_io(dio_bio, err);
7046 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
7047 struct bio *bio, int mirror_num,
7048 unsigned long bio_flags, u64 offset)
7051 struct btrfs_root *root = BTRFS_I(inode)->root;
7052 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
7053 BUG_ON(ret); /* -ENOMEM */
7057 static void btrfs_end_dio_bio(struct bio *bio, int err)
7059 struct btrfs_dio_private *dip = bio->bi_private;
7062 btrfs_err(BTRFS_I(dip->inode)->root->fs_info,
7063 "direct IO failed ino %llu rw %lu sector %#Lx len %u err no %d",
7064 btrfs_ino(dip->inode), bio->bi_rw,
7065 (unsigned long long)bio->bi_sector, bio->bi_size, err);
7069 * before atomic variable goto zero, we must make sure
7070 * dip->errors is perceived to be set.
7072 smp_mb__before_atomic_dec();
7075 /* if there are more bios still pending for this dio, just exit */
7076 if (!atomic_dec_and_test(&dip->pending_bios))
7080 bio_io_error(dip->orig_bio);
7082 set_bit(BIO_UPTODATE, &dip->dio_bio->bi_flags);
7083 bio_endio(dip->orig_bio, 0);
7089 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
7090 u64 first_sector, gfp_t gfp_flags)
7092 int nr_vecs = bio_get_nr_vecs(bdev);
7093 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
7096 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
7097 int rw, u64 file_offset, int skip_sum,
7100 struct btrfs_dio_private *dip = bio->bi_private;
7101 int write = rw & REQ_WRITE;
7102 struct btrfs_root *root = BTRFS_I(inode)->root;
7106 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
7111 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
7119 if (write && async_submit) {
7120 ret = btrfs_wq_submit_bio(root->fs_info,
7121 inode, rw, bio, 0, 0,
7123 __btrfs_submit_bio_start_direct_io,
7124 __btrfs_submit_bio_done);
7128 * If we aren't doing async submit, calculate the csum of the
7131 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
7134 } else if (!skip_sum) {
7135 ret = btrfs_lookup_bio_sums_dio(root, inode, dip, bio,
7142 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
7148 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
7151 struct inode *inode = dip->inode;
7152 struct btrfs_root *root = BTRFS_I(inode)->root;
7154 struct bio *orig_bio = dip->orig_bio;
7155 struct bio_vec *bvec = orig_bio->bi_io_vec;
7156 u64 start_sector = orig_bio->bi_sector;
7157 u64 file_offset = dip->logical_offset;
7162 int async_submit = 0;
7164 map_length = orig_bio->bi_size;
7165 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9,
7166 &map_length, NULL, 0);
7172 if (map_length >= orig_bio->bi_size) {
7177 /* async crcs make it difficult to collect full stripe writes. */
7178 if (btrfs_get_alloc_profile(root, 1) &
7179 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
7184 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
7187 bio->bi_private = dip;
7188 bio->bi_end_io = btrfs_end_dio_bio;
7189 atomic_inc(&dip->pending_bios);
7191 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
7192 if (unlikely(map_length < submit_len + bvec->bv_len ||
7193 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
7194 bvec->bv_offset) < bvec->bv_len)) {
7196 * inc the count before we submit the bio so
7197 * we know the end IO handler won't happen before
7198 * we inc the count. Otherwise, the dip might get freed
7199 * before we're done setting it up
7201 atomic_inc(&dip->pending_bios);
7202 ret = __btrfs_submit_dio_bio(bio, inode, rw,
7203 file_offset, skip_sum,
7207 atomic_dec(&dip->pending_bios);
7211 start_sector += submit_len >> 9;
7212 file_offset += submit_len;
7217 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
7218 start_sector, GFP_NOFS);
7221 bio->bi_private = dip;
7222 bio->bi_end_io = btrfs_end_dio_bio;
7224 map_length = orig_bio->bi_size;
7225 ret = btrfs_map_block(root->fs_info, rw,
7227 &map_length, NULL, 0);
7233 submit_len += bvec->bv_len;
7240 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
7249 * before atomic variable goto zero, we must
7250 * make sure dip->errors is perceived to be set.
7252 smp_mb__before_atomic_dec();
7253 if (atomic_dec_and_test(&dip->pending_bios))
7254 bio_io_error(dip->orig_bio);
7256 /* bio_end_io() will handle error, so we needn't return it */
7260 static void btrfs_submit_direct(int rw, struct bio *dio_bio,
7261 struct inode *inode, loff_t file_offset)
7263 struct btrfs_root *root = BTRFS_I(inode)->root;
7264 struct btrfs_dio_private *dip;
7268 int write = rw & REQ_WRITE;
7272 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
7274 io_bio = btrfs_bio_clone(dio_bio, GFP_NOFS);
7280 if (!skip_sum && !write) {
7281 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
7282 sum_len = dio_bio->bi_size >> inode->i_sb->s_blocksize_bits;
7283 sum_len *= csum_size;
7288 dip = kmalloc(sizeof(*dip) + sum_len, GFP_NOFS);
7294 dip->private = dio_bio->bi_private;
7296 dip->logical_offset = file_offset;
7297 dip->bytes = dio_bio->bi_size;
7298 dip->disk_bytenr = (u64)dio_bio->bi_sector << 9;
7299 io_bio->bi_private = dip;
7301 dip->orig_bio = io_bio;
7302 dip->dio_bio = dio_bio;
7303 atomic_set(&dip->pending_bios, 0);
7306 io_bio->bi_end_io = btrfs_endio_direct_write;
7308 io_bio->bi_end_io = btrfs_endio_direct_read;
7310 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
7319 * If this is a write, we need to clean up the reserved space and kill
7320 * the ordered extent.
7323 struct btrfs_ordered_extent *ordered;
7324 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
7325 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
7326 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
7327 btrfs_free_reserved_extent(root, ordered->start,
7329 btrfs_put_ordered_extent(ordered);
7330 btrfs_put_ordered_extent(ordered);
7332 bio_endio(dio_bio, ret);
7335 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
7336 const struct iovec *iov, loff_t offset,
7337 unsigned long nr_segs)
7343 unsigned blocksize_mask = root->sectorsize - 1;
7344 ssize_t retval = -EINVAL;
7345 loff_t end = offset;
7347 if (offset & blocksize_mask)
7350 /* Check the memory alignment. Blocks cannot straddle pages */
7351 for (seg = 0; seg < nr_segs; seg++) {
7352 addr = (unsigned long)iov[seg].iov_base;
7353 size = iov[seg].iov_len;
7355 if ((addr & blocksize_mask) || (size & blocksize_mask))
7358 /* If this is a write we don't need to check anymore */
7363 * Check to make sure we don't have duplicate iov_base's in this
7364 * iovec, if so return EINVAL, otherwise we'll get csum errors
7365 * when reading back.
7367 for (i = seg + 1; i < nr_segs; i++) {
7368 if (iov[seg].iov_base == iov[i].iov_base)
7377 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
7378 const struct iovec *iov, loff_t offset,
7379 unsigned long nr_segs)
7381 struct file *file = iocb->ki_filp;
7382 struct inode *inode = file->f_mapping->host;
7386 bool relock = false;
7389 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
7393 atomic_inc(&inode->i_dio_count);
7394 smp_mb__after_atomic_inc();
7397 * The generic stuff only does filemap_write_and_wait_range, which isn't
7398 * enough if we've written compressed pages to this area, so we need to
7399 * call btrfs_wait_ordered_range to make absolutely sure that any
7400 * outstanding dirty pages are on disk.
7402 count = iov_length(iov, nr_segs);
7403 ret = btrfs_wait_ordered_range(inode, offset, count);
7409 * If the write DIO is beyond the EOF, we need update
7410 * the isize, but it is protected by i_mutex. So we can
7411 * not unlock the i_mutex at this case.
7413 if (offset + count <= inode->i_size) {
7414 mutex_unlock(&inode->i_mutex);
7417 ret = btrfs_delalloc_reserve_space(inode, count);
7420 } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7421 &BTRFS_I(inode)->runtime_flags))) {
7422 inode_dio_done(inode);
7423 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7427 ret = __blockdev_direct_IO(rw, iocb, inode,
7428 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
7429 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
7430 btrfs_submit_direct, flags);
7432 if (ret < 0 && ret != -EIOCBQUEUED)
7433 btrfs_delalloc_release_space(inode, count);
7434 else if (ret >= 0 && (size_t)ret < count)
7435 btrfs_delalloc_release_space(inode,
7436 count - (size_t)ret);
7438 btrfs_delalloc_release_metadata(inode, 0);
7442 inode_dio_done(inode);
7444 mutex_lock(&inode->i_mutex);
7449 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7451 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7452 __u64 start, __u64 len)
7456 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7460 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
7463 int btrfs_readpage(struct file *file, struct page *page)
7465 struct extent_io_tree *tree;
7466 tree = &BTRFS_I(page->mapping->host)->io_tree;
7467 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
7470 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
7472 struct extent_io_tree *tree;
7475 if (current->flags & PF_MEMALLOC) {
7476 redirty_page_for_writepage(wbc, page);
7480 tree = &BTRFS_I(page->mapping->host)->io_tree;
7481 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
7484 static int btrfs_writepages(struct address_space *mapping,
7485 struct writeback_control *wbc)
7487 struct extent_io_tree *tree;
7489 tree = &BTRFS_I(mapping->host)->io_tree;
7490 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
7494 btrfs_readpages(struct file *file, struct address_space *mapping,
7495 struct list_head *pages, unsigned nr_pages)
7497 struct extent_io_tree *tree;
7498 tree = &BTRFS_I(mapping->host)->io_tree;
7499 return extent_readpages(tree, mapping, pages, nr_pages,
7502 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7504 struct extent_io_tree *tree;
7505 struct extent_map_tree *map;
7508 tree = &BTRFS_I(page->mapping->host)->io_tree;
7509 map = &BTRFS_I(page->mapping->host)->extent_tree;
7510 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
7512 ClearPagePrivate(page);
7513 set_page_private(page, 0);
7514 page_cache_release(page);
7519 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7521 if (PageWriteback(page) || PageDirty(page))
7523 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
7526 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
7527 unsigned int length)
7529 struct inode *inode = page->mapping->host;
7530 struct extent_io_tree *tree;
7531 struct btrfs_ordered_extent *ordered;
7532 struct extent_state *cached_state = NULL;
7533 u64 page_start = page_offset(page);
7534 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
7535 int inode_evicting = inode->i_state & I_FREEING;
7538 * we have the page locked, so new writeback can't start,
7539 * and the dirty bit won't be cleared while we are here.
7541 * Wait for IO on this page so that we can safely clear
7542 * the PagePrivate2 bit and do ordered accounting
7544 wait_on_page_writeback(page);
7546 tree = &BTRFS_I(inode)->io_tree;
7548 btrfs_releasepage(page, GFP_NOFS);
7552 if (!inode_evicting)
7553 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7554 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7557 * IO on this page will never be started, so we need
7558 * to account for any ordered extents now
7560 if (!inode_evicting)
7561 clear_extent_bit(tree, page_start, page_end,
7562 EXTENT_DIRTY | EXTENT_DELALLOC |
7563 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
7564 EXTENT_DEFRAG, 1, 0, &cached_state,
7567 * whoever cleared the private bit is responsible
7568 * for the finish_ordered_io
7570 if (TestClearPagePrivate2(page)) {
7571 struct btrfs_ordered_inode_tree *tree;
7574 tree = &BTRFS_I(inode)->ordered_tree;
7576 spin_lock_irq(&tree->lock);
7577 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
7578 new_len = page_start - ordered->file_offset;
7579 if (new_len < ordered->truncated_len)
7580 ordered->truncated_len = new_len;
7581 spin_unlock_irq(&tree->lock);
7583 if (btrfs_dec_test_ordered_pending(inode, &ordered,
7585 PAGE_CACHE_SIZE, 1))
7586 btrfs_finish_ordered_io(ordered);
7588 btrfs_put_ordered_extent(ordered);
7589 if (!inode_evicting) {
7590 cached_state = NULL;
7591 lock_extent_bits(tree, page_start, page_end, 0,
7596 if (!inode_evicting) {
7597 clear_extent_bit(tree, page_start, page_end,
7598 EXTENT_LOCKED | EXTENT_DIRTY |
7599 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
7600 EXTENT_DEFRAG, 1, 1,
7601 &cached_state, GFP_NOFS);
7603 __btrfs_releasepage(page, GFP_NOFS);
7606 ClearPageChecked(page);
7607 if (PagePrivate(page)) {
7608 ClearPagePrivate(page);
7609 set_page_private(page, 0);
7610 page_cache_release(page);
7615 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
7616 * called from a page fault handler when a page is first dirtied. Hence we must
7617 * be careful to check for EOF conditions here. We set the page up correctly
7618 * for a written page which means we get ENOSPC checking when writing into
7619 * holes and correct delalloc and unwritten extent mapping on filesystems that
7620 * support these features.
7622 * We are not allowed to take the i_mutex here so we have to play games to
7623 * protect against truncate races as the page could now be beyond EOF. Because
7624 * vmtruncate() writes the inode size before removing pages, once we have the
7625 * page lock we can determine safely if the page is beyond EOF. If it is not
7626 * beyond EOF, then the page is guaranteed safe against truncation until we
7629 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
7631 struct page *page = vmf->page;
7632 struct inode *inode = file_inode(vma->vm_file);
7633 struct btrfs_root *root = BTRFS_I(inode)->root;
7634 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7635 struct btrfs_ordered_extent *ordered;
7636 struct extent_state *cached_state = NULL;
7638 unsigned long zero_start;
7645 sb_start_pagefault(inode->i_sb);
7646 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
7648 ret = file_update_time(vma->vm_file);
7654 else /* -ENOSPC, -EIO, etc */
7655 ret = VM_FAULT_SIGBUS;
7661 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
7664 size = i_size_read(inode);
7665 page_start = page_offset(page);
7666 page_end = page_start + PAGE_CACHE_SIZE - 1;
7668 if ((page->mapping != inode->i_mapping) ||
7669 (page_start >= size)) {
7670 /* page got truncated out from underneath us */
7673 wait_on_page_writeback(page);
7675 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
7676 set_page_extent_mapped(page);
7679 * we can't set the delalloc bits if there are pending ordered
7680 * extents. Drop our locks and wait for them to finish
7682 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7684 unlock_extent_cached(io_tree, page_start, page_end,
7685 &cached_state, GFP_NOFS);
7687 btrfs_start_ordered_extent(inode, ordered, 1);
7688 btrfs_put_ordered_extent(ordered);
7693 * XXX - page_mkwrite gets called every time the page is dirtied, even
7694 * if it was already dirty, so for space accounting reasons we need to
7695 * clear any delalloc bits for the range we are fixing to save. There
7696 * is probably a better way to do this, but for now keep consistent with
7697 * prepare_pages in the normal write path.
7699 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
7700 EXTENT_DIRTY | EXTENT_DELALLOC |
7701 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
7702 0, 0, &cached_state, GFP_NOFS);
7704 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
7707 unlock_extent_cached(io_tree, page_start, page_end,
7708 &cached_state, GFP_NOFS);
7709 ret = VM_FAULT_SIGBUS;
7714 /* page is wholly or partially inside EOF */
7715 if (page_start + PAGE_CACHE_SIZE > size)
7716 zero_start = size & ~PAGE_CACHE_MASK;
7718 zero_start = PAGE_CACHE_SIZE;
7720 if (zero_start != PAGE_CACHE_SIZE) {
7722 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
7723 flush_dcache_page(page);
7726 ClearPageChecked(page);
7727 set_page_dirty(page);
7728 SetPageUptodate(page);
7730 BTRFS_I(inode)->last_trans = root->fs_info->generation;
7731 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
7732 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
7734 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
7738 sb_end_pagefault(inode->i_sb);
7739 return VM_FAULT_LOCKED;
7743 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
7745 sb_end_pagefault(inode->i_sb);
7749 static int btrfs_truncate(struct inode *inode)
7751 struct btrfs_root *root = BTRFS_I(inode)->root;
7752 struct btrfs_block_rsv *rsv;
7755 struct btrfs_trans_handle *trans;
7756 u64 mask = root->sectorsize - 1;
7757 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
7759 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
7765 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
7766 * 3 things going on here
7768 * 1) We need to reserve space for our orphan item and the space to
7769 * delete our orphan item. Lord knows we don't want to have a dangling
7770 * orphan item because we didn't reserve space to remove it.
7772 * 2) We need to reserve space to update our inode.
7774 * 3) We need to have something to cache all the space that is going to
7775 * be free'd up by the truncate operation, but also have some slack
7776 * space reserved in case it uses space during the truncate (thank you
7777 * very much snapshotting).
7779 * And we need these to all be seperate. The fact is we can use alot of
7780 * space doing the truncate, and we have no earthly idea how much space
7781 * we will use, so we need the truncate reservation to be seperate so it
7782 * doesn't end up using space reserved for updating the inode or
7783 * removing the orphan item. We also need to be able to stop the
7784 * transaction and start a new one, which means we need to be able to
7785 * update the inode several times, and we have no idea of knowing how
7786 * many times that will be, so we can't just reserve 1 item for the
7787 * entirety of the opration, so that has to be done seperately as well.
7788 * Then there is the orphan item, which does indeed need to be held on
7789 * to for the whole operation, and we need nobody to touch this reserved
7790 * space except the orphan code.
7792 * So that leaves us with
7794 * 1) root->orphan_block_rsv - for the orphan deletion.
7795 * 2) rsv - for the truncate reservation, which we will steal from the
7796 * transaction reservation.
7797 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
7798 * updating the inode.
7800 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
7803 rsv->size = min_size;
7807 * 1 for the truncate slack space
7808 * 1 for updating the inode.
7810 trans = btrfs_start_transaction(root, 2);
7811 if (IS_ERR(trans)) {
7812 err = PTR_ERR(trans);
7816 /* Migrate the slack space for the truncate to our reserve */
7817 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
7822 * setattr is responsible for setting the ordered_data_close flag,
7823 * but that is only tested during the last file release. That
7824 * could happen well after the next commit, leaving a great big
7825 * window where new writes may get lost if someone chooses to write
7826 * to this file after truncating to zero
7828 * The inode doesn't have any dirty data here, and so if we commit
7829 * this is a noop. If someone immediately starts writing to the inode
7830 * it is very likely we'll catch some of their writes in this
7831 * transaction, and the commit will find this file on the ordered
7832 * data list with good things to send down.
7834 * This is a best effort solution, there is still a window where
7835 * using truncate to replace the contents of the file will
7836 * end up with a zero length file after a crash.
7838 if (inode->i_size == 0 && test_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
7839 &BTRFS_I(inode)->runtime_flags))
7840 btrfs_add_ordered_operation(trans, root, inode);
7843 * So if we truncate and then write and fsync we normally would just
7844 * write the extents that changed, which is a problem if we need to
7845 * first truncate that entire inode. So set this flag so we write out
7846 * all of the extents in the inode to the sync log so we're completely
7849 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
7850 trans->block_rsv = rsv;
7853 ret = btrfs_truncate_inode_items(trans, root, inode,
7855 BTRFS_EXTENT_DATA_KEY);
7856 if (ret != -ENOSPC) {
7861 trans->block_rsv = &root->fs_info->trans_block_rsv;
7862 ret = btrfs_update_inode(trans, root, inode);
7868 btrfs_end_transaction(trans, root);
7869 btrfs_btree_balance_dirty(root);
7871 trans = btrfs_start_transaction(root, 2);
7872 if (IS_ERR(trans)) {
7873 ret = err = PTR_ERR(trans);
7878 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
7880 BUG_ON(ret); /* shouldn't happen */
7881 trans->block_rsv = rsv;
7884 if (ret == 0 && inode->i_nlink > 0) {
7885 trans->block_rsv = root->orphan_block_rsv;
7886 ret = btrfs_orphan_del(trans, inode);
7892 trans->block_rsv = &root->fs_info->trans_block_rsv;
7893 ret = btrfs_update_inode(trans, root, inode);
7897 ret = btrfs_end_transaction(trans, root);
7898 btrfs_btree_balance_dirty(root);
7902 btrfs_free_block_rsv(root, rsv);
7911 * create a new subvolume directory/inode (helper for the ioctl).
7913 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
7914 struct btrfs_root *new_root,
7915 struct btrfs_root *parent_root,
7918 struct inode *inode;
7922 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
7923 new_dirid, new_dirid,
7924 S_IFDIR | (~current_umask() & S_IRWXUGO),
7927 return PTR_ERR(inode);
7928 inode->i_op = &btrfs_dir_inode_operations;
7929 inode->i_fop = &btrfs_dir_file_operations;
7931 set_nlink(inode, 1);
7932 btrfs_i_size_write(inode, 0);
7934 err = btrfs_subvol_inherit_props(trans, new_root, parent_root);
7936 btrfs_err(new_root->fs_info,
7937 "error inheriting subvolume %llu properties: %d\n",
7938 new_root->root_key.objectid, err);
7940 err = btrfs_update_inode(trans, new_root, inode);
7946 struct inode *btrfs_alloc_inode(struct super_block *sb)
7948 struct btrfs_inode *ei;
7949 struct inode *inode;
7951 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
7958 ei->last_sub_trans = 0;
7959 ei->logged_trans = 0;
7960 ei->delalloc_bytes = 0;
7961 ei->disk_i_size = 0;
7964 ei->index_cnt = (u64)-1;
7966 ei->last_unlink_trans = 0;
7967 ei->last_log_commit = 0;
7969 spin_lock_init(&ei->lock);
7970 ei->outstanding_extents = 0;
7971 ei->reserved_extents = 0;
7973 ei->runtime_flags = 0;
7974 ei->force_compress = BTRFS_COMPRESS_NONE;
7976 ei->delayed_node = NULL;
7978 inode = &ei->vfs_inode;
7979 extent_map_tree_init(&ei->extent_tree);
7980 extent_io_tree_init(&ei->io_tree, &inode->i_data);
7981 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
7982 ei->io_tree.track_uptodate = 1;
7983 ei->io_failure_tree.track_uptodate = 1;
7984 atomic_set(&ei->sync_writers, 0);
7985 mutex_init(&ei->log_mutex);
7986 mutex_init(&ei->delalloc_mutex);
7987 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
7988 INIT_LIST_HEAD(&ei->delalloc_inodes);
7989 INIT_LIST_HEAD(&ei->ordered_operations);
7990 RB_CLEAR_NODE(&ei->rb_node);
7995 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
7996 void btrfs_test_destroy_inode(struct inode *inode)
7998 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
7999 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8003 static void btrfs_i_callback(struct rcu_head *head)
8005 struct inode *inode = container_of(head, struct inode, i_rcu);
8006 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8009 void btrfs_destroy_inode(struct inode *inode)
8011 struct btrfs_ordered_extent *ordered;
8012 struct btrfs_root *root = BTRFS_I(inode)->root;
8014 WARN_ON(!hlist_empty(&inode->i_dentry));
8015 WARN_ON(inode->i_data.nrpages);
8016 WARN_ON(BTRFS_I(inode)->outstanding_extents);
8017 WARN_ON(BTRFS_I(inode)->reserved_extents);
8018 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
8019 WARN_ON(BTRFS_I(inode)->csum_bytes);
8022 * This can happen where we create an inode, but somebody else also
8023 * created the same inode and we need to destroy the one we already
8030 * Make sure we're properly removed from the ordered operation
8034 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
8035 spin_lock(&root->fs_info->ordered_root_lock);
8036 list_del_init(&BTRFS_I(inode)->ordered_operations);
8037 spin_unlock(&root->fs_info->ordered_root_lock);
8040 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
8041 &BTRFS_I(inode)->runtime_flags)) {
8042 btrfs_info(root->fs_info, "inode %llu still on the orphan list",
8044 atomic_dec(&root->orphan_inodes);
8048 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
8052 btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup",
8053 ordered->file_offset, ordered->len);
8054 btrfs_remove_ordered_extent(inode, ordered);
8055 btrfs_put_ordered_extent(ordered);
8056 btrfs_put_ordered_extent(ordered);
8059 inode_tree_del(inode);
8060 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
8062 call_rcu(&inode->i_rcu, btrfs_i_callback);
8065 int btrfs_drop_inode(struct inode *inode)
8067 struct btrfs_root *root = BTRFS_I(inode)->root;
8072 /* the snap/subvol tree is on deleting */
8073 if (btrfs_root_refs(&root->root_item) == 0)
8076 return generic_drop_inode(inode);
8079 static void init_once(void *foo)
8081 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
8083 inode_init_once(&ei->vfs_inode);
8086 void btrfs_destroy_cachep(void)
8089 * Make sure all delayed rcu free inodes are flushed before we
8093 if (btrfs_inode_cachep)
8094 kmem_cache_destroy(btrfs_inode_cachep);
8095 if (btrfs_trans_handle_cachep)
8096 kmem_cache_destroy(btrfs_trans_handle_cachep);
8097 if (btrfs_transaction_cachep)
8098 kmem_cache_destroy(btrfs_transaction_cachep);
8099 if (btrfs_path_cachep)
8100 kmem_cache_destroy(btrfs_path_cachep);
8101 if (btrfs_free_space_cachep)
8102 kmem_cache_destroy(btrfs_free_space_cachep);
8103 if (btrfs_delalloc_work_cachep)
8104 kmem_cache_destroy(btrfs_delalloc_work_cachep);
8107 int btrfs_init_cachep(void)
8109 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
8110 sizeof(struct btrfs_inode), 0,
8111 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
8112 if (!btrfs_inode_cachep)
8115 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
8116 sizeof(struct btrfs_trans_handle), 0,
8117 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8118 if (!btrfs_trans_handle_cachep)
8121 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
8122 sizeof(struct btrfs_transaction), 0,
8123 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8124 if (!btrfs_transaction_cachep)
8127 btrfs_path_cachep = kmem_cache_create("btrfs_path",
8128 sizeof(struct btrfs_path), 0,
8129 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8130 if (!btrfs_path_cachep)
8133 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
8134 sizeof(struct btrfs_free_space), 0,
8135 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8136 if (!btrfs_free_space_cachep)
8139 btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
8140 sizeof(struct btrfs_delalloc_work), 0,
8141 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
8143 if (!btrfs_delalloc_work_cachep)
8148 btrfs_destroy_cachep();
8152 static int btrfs_getattr(struct vfsmount *mnt,
8153 struct dentry *dentry, struct kstat *stat)
8156 struct inode *inode = dentry->d_inode;
8157 u32 blocksize = inode->i_sb->s_blocksize;
8159 generic_fillattr(inode, stat);
8160 stat->dev = BTRFS_I(inode)->root->anon_dev;
8161 stat->blksize = PAGE_CACHE_SIZE;
8163 spin_lock(&BTRFS_I(inode)->lock);
8164 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
8165 spin_unlock(&BTRFS_I(inode)->lock);
8166 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
8167 ALIGN(delalloc_bytes, blocksize)) >> 9;
8171 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
8172 struct inode *new_dir, struct dentry *new_dentry)
8174 struct btrfs_trans_handle *trans;
8175 struct btrfs_root *root = BTRFS_I(old_dir)->root;
8176 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
8177 struct inode *new_inode = new_dentry->d_inode;
8178 struct inode *old_inode = old_dentry->d_inode;
8179 struct timespec ctime = CURRENT_TIME;
8183 u64 old_ino = btrfs_ino(old_inode);
8185 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
8188 /* we only allow rename subvolume link between subvolumes */
8189 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
8192 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
8193 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
8196 if (S_ISDIR(old_inode->i_mode) && new_inode &&
8197 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
8201 /* check for collisions, even if the name isn't there */
8202 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
8203 new_dentry->d_name.name,
8204 new_dentry->d_name.len);
8207 if (ret == -EEXIST) {
8209 * eexist without a new_inode */
8210 if (WARN_ON(!new_inode)) {
8214 /* maybe -EOVERFLOW */
8221 * we're using rename to replace one file with another.
8222 * and the replacement file is large. Start IO on it now so
8223 * we don't add too much work to the end of the transaction
8225 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
8226 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
8227 filemap_flush(old_inode->i_mapping);
8229 /* close the racy window with snapshot create/destroy ioctl */
8230 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8231 down_read(&root->fs_info->subvol_sem);
8233 * We want to reserve the absolute worst case amount of items. So if
8234 * both inodes are subvols and we need to unlink them then that would
8235 * require 4 item modifications, but if they are both normal inodes it
8236 * would require 5 item modifications, so we'll assume their normal
8237 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
8238 * should cover the worst case number of items we'll modify.
8240 trans = btrfs_start_transaction(root, 11);
8241 if (IS_ERR(trans)) {
8242 ret = PTR_ERR(trans);
8247 btrfs_record_root_in_trans(trans, dest);
8249 ret = btrfs_set_inode_index(new_dir, &index);
8253 BTRFS_I(old_inode)->dir_index = 0ULL;
8254 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8255 /* force full log commit if subvolume involved. */
8256 root->fs_info->last_trans_log_full_commit = trans->transid;
8258 ret = btrfs_insert_inode_ref(trans, dest,
8259 new_dentry->d_name.name,
8260 new_dentry->d_name.len,
8262 btrfs_ino(new_dir), index);
8266 * this is an ugly little race, but the rename is required
8267 * to make sure that if we crash, the inode is either at the
8268 * old name or the new one. pinning the log transaction lets
8269 * us make sure we don't allow a log commit to come in after
8270 * we unlink the name but before we add the new name back in.
8272 btrfs_pin_log_trans(root);
8275 * make sure the inode gets flushed if it is replacing
8278 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
8279 btrfs_add_ordered_operation(trans, root, old_inode);
8281 inode_inc_iversion(old_dir);
8282 inode_inc_iversion(new_dir);
8283 inode_inc_iversion(old_inode);
8284 old_dir->i_ctime = old_dir->i_mtime = ctime;
8285 new_dir->i_ctime = new_dir->i_mtime = ctime;
8286 old_inode->i_ctime = ctime;
8288 if (old_dentry->d_parent != new_dentry->d_parent)
8289 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
8291 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8292 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
8293 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
8294 old_dentry->d_name.name,
8295 old_dentry->d_name.len);
8297 ret = __btrfs_unlink_inode(trans, root, old_dir,
8298 old_dentry->d_inode,
8299 old_dentry->d_name.name,
8300 old_dentry->d_name.len);
8302 ret = btrfs_update_inode(trans, root, old_inode);
8305 btrfs_abort_transaction(trans, root, ret);
8310 inode_inc_iversion(new_inode);
8311 new_inode->i_ctime = CURRENT_TIME;
8312 if (unlikely(btrfs_ino(new_inode) ==
8313 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
8314 root_objectid = BTRFS_I(new_inode)->location.objectid;
8315 ret = btrfs_unlink_subvol(trans, dest, new_dir,
8317 new_dentry->d_name.name,
8318 new_dentry->d_name.len);
8319 BUG_ON(new_inode->i_nlink == 0);
8321 ret = btrfs_unlink_inode(trans, dest, new_dir,
8322 new_dentry->d_inode,
8323 new_dentry->d_name.name,
8324 new_dentry->d_name.len);
8326 if (!ret && new_inode->i_nlink == 0)
8327 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
8329 btrfs_abort_transaction(trans, root, ret);
8334 ret = btrfs_add_link(trans, new_dir, old_inode,
8335 new_dentry->d_name.name,
8336 new_dentry->d_name.len, 0, index);
8338 btrfs_abort_transaction(trans, root, ret);
8342 if (old_inode->i_nlink == 1)
8343 BTRFS_I(old_inode)->dir_index = index;
8345 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
8346 struct dentry *parent = new_dentry->d_parent;
8347 btrfs_log_new_name(trans, old_inode, old_dir, parent);
8348 btrfs_end_log_trans(root);
8351 btrfs_end_transaction(trans, root);
8353 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8354 up_read(&root->fs_info->subvol_sem);
8359 static void btrfs_run_delalloc_work(struct btrfs_work *work)
8361 struct btrfs_delalloc_work *delalloc_work;
8362 struct inode *inode;
8364 delalloc_work = container_of(work, struct btrfs_delalloc_work,
8366 inode = delalloc_work->inode;
8367 if (delalloc_work->wait) {
8368 btrfs_wait_ordered_range(inode, 0, (u64)-1);
8370 filemap_flush(inode->i_mapping);
8371 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
8372 &BTRFS_I(inode)->runtime_flags))
8373 filemap_flush(inode->i_mapping);
8376 if (delalloc_work->delay_iput)
8377 btrfs_add_delayed_iput(inode);
8380 complete(&delalloc_work->completion);
8383 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
8384 int wait, int delay_iput)
8386 struct btrfs_delalloc_work *work;
8388 work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
8392 init_completion(&work->completion);
8393 INIT_LIST_HEAD(&work->list);
8394 work->inode = inode;
8396 work->delay_iput = delay_iput;
8397 work->work.func = btrfs_run_delalloc_work;
8402 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
8404 wait_for_completion(&work->completion);
8405 kmem_cache_free(btrfs_delalloc_work_cachep, work);
8409 * some fairly slow code that needs optimization. This walks the list
8410 * of all the inodes with pending delalloc and forces them to disk.
8412 static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8414 struct btrfs_inode *binode;
8415 struct inode *inode;
8416 struct btrfs_delalloc_work *work, *next;
8417 struct list_head works;
8418 struct list_head splice;
8421 INIT_LIST_HEAD(&works);
8422 INIT_LIST_HEAD(&splice);
8424 spin_lock(&root->delalloc_lock);
8425 list_splice_init(&root->delalloc_inodes, &splice);
8426 while (!list_empty(&splice)) {
8427 binode = list_entry(splice.next, struct btrfs_inode,
8430 list_move_tail(&binode->delalloc_inodes,
8431 &root->delalloc_inodes);
8432 inode = igrab(&binode->vfs_inode);
8434 cond_resched_lock(&root->delalloc_lock);
8437 spin_unlock(&root->delalloc_lock);
8439 work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
8440 if (unlikely(!work)) {
8442 btrfs_add_delayed_iput(inode);
8448 list_add_tail(&work->list, &works);
8449 btrfs_queue_worker(&root->fs_info->flush_workers,
8453 spin_lock(&root->delalloc_lock);
8455 spin_unlock(&root->delalloc_lock);
8457 list_for_each_entry_safe(work, next, &works, list) {
8458 list_del_init(&work->list);
8459 btrfs_wait_and_free_delalloc_work(work);
8463 list_for_each_entry_safe(work, next, &works, list) {
8464 list_del_init(&work->list);
8465 btrfs_wait_and_free_delalloc_work(work);
8468 if (!list_empty_careful(&splice)) {
8469 spin_lock(&root->delalloc_lock);
8470 list_splice_tail(&splice, &root->delalloc_inodes);
8471 spin_unlock(&root->delalloc_lock);
8476 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8480 if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state))
8483 ret = __start_delalloc_inodes(root, delay_iput);
8485 * the filemap_flush will queue IO into the worker threads, but
8486 * we have to make sure the IO is actually started and that
8487 * ordered extents get created before we return
8489 atomic_inc(&root->fs_info->async_submit_draining);
8490 while (atomic_read(&root->fs_info->nr_async_submits) ||
8491 atomic_read(&root->fs_info->async_delalloc_pages)) {
8492 wait_event(root->fs_info->async_submit_wait,
8493 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
8494 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
8496 atomic_dec(&root->fs_info->async_submit_draining);
8500 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput)
8502 struct btrfs_root *root;
8503 struct list_head splice;
8506 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
8509 INIT_LIST_HEAD(&splice);
8511 spin_lock(&fs_info->delalloc_root_lock);
8512 list_splice_init(&fs_info->delalloc_roots, &splice);
8513 while (!list_empty(&splice)) {
8514 root = list_first_entry(&splice, struct btrfs_root,
8516 root = btrfs_grab_fs_root(root);
8518 list_move_tail(&root->delalloc_root,
8519 &fs_info->delalloc_roots);
8520 spin_unlock(&fs_info->delalloc_root_lock);
8522 ret = __start_delalloc_inodes(root, delay_iput);
8523 btrfs_put_fs_root(root);
8527 spin_lock(&fs_info->delalloc_root_lock);
8529 spin_unlock(&fs_info->delalloc_root_lock);
8531 atomic_inc(&fs_info->async_submit_draining);
8532 while (atomic_read(&fs_info->nr_async_submits) ||
8533 atomic_read(&fs_info->async_delalloc_pages)) {
8534 wait_event(fs_info->async_submit_wait,
8535 (atomic_read(&fs_info->nr_async_submits) == 0 &&
8536 atomic_read(&fs_info->async_delalloc_pages) == 0));
8538 atomic_dec(&fs_info->async_submit_draining);
8541 if (!list_empty_careful(&splice)) {
8542 spin_lock(&fs_info->delalloc_root_lock);
8543 list_splice_tail(&splice, &fs_info->delalloc_roots);
8544 spin_unlock(&fs_info->delalloc_root_lock);
8549 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
8550 const char *symname)
8552 struct btrfs_trans_handle *trans;
8553 struct btrfs_root *root = BTRFS_I(dir)->root;
8554 struct btrfs_path *path;
8555 struct btrfs_key key;
8556 struct inode *inode = NULL;
8564 struct btrfs_file_extent_item *ei;
8565 struct extent_buffer *leaf;
8567 name_len = strlen(symname);
8568 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
8569 return -ENAMETOOLONG;
8572 * 2 items for inode item and ref
8573 * 2 items for dir items
8574 * 1 item for xattr if selinux is on
8576 trans = btrfs_start_transaction(root, 5);
8578 return PTR_ERR(trans);
8580 err = btrfs_find_free_ino(root, &objectid);
8584 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
8585 dentry->d_name.len, btrfs_ino(dir), objectid,
8586 S_IFLNK|S_IRWXUGO, &index);
8587 if (IS_ERR(inode)) {
8588 err = PTR_ERR(inode);
8592 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
8599 * If the active LSM wants to access the inode during
8600 * d_instantiate it needs these. Smack checks to see
8601 * if the filesystem supports xattrs by looking at the
8604 inode->i_fop = &btrfs_file_operations;
8605 inode->i_op = &btrfs_file_inode_operations;
8607 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
8611 inode->i_mapping->a_ops = &btrfs_aops;
8612 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8613 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
8618 path = btrfs_alloc_path();
8624 key.objectid = btrfs_ino(inode);
8626 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
8627 datasize = btrfs_file_extent_calc_inline_size(name_len);
8628 err = btrfs_insert_empty_item(trans, root, path, &key,
8632 btrfs_free_path(path);
8635 leaf = path->nodes[0];
8636 ei = btrfs_item_ptr(leaf, path->slots[0],
8637 struct btrfs_file_extent_item);
8638 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
8639 btrfs_set_file_extent_type(leaf, ei,
8640 BTRFS_FILE_EXTENT_INLINE);
8641 btrfs_set_file_extent_encryption(leaf, ei, 0);
8642 btrfs_set_file_extent_compression(leaf, ei, 0);
8643 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
8644 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
8646 ptr = btrfs_file_extent_inline_start(ei);
8647 write_extent_buffer(leaf, symname, ptr, name_len);
8648 btrfs_mark_buffer_dirty(leaf);
8649 btrfs_free_path(path);
8651 inode->i_op = &btrfs_symlink_inode_operations;
8652 inode->i_mapping->a_ops = &btrfs_symlink_aops;
8653 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8654 inode_set_bytes(inode, name_len);
8655 btrfs_i_size_write(inode, name_len);
8656 err = btrfs_update_inode(trans, root, inode);
8662 d_instantiate(dentry, inode);
8663 btrfs_end_transaction(trans, root);
8665 inode_dec_link_count(inode);
8668 btrfs_btree_balance_dirty(root);
8672 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
8673 u64 start, u64 num_bytes, u64 min_size,
8674 loff_t actual_len, u64 *alloc_hint,
8675 struct btrfs_trans_handle *trans)
8677 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
8678 struct extent_map *em;
8679 struct btrfs_root *root = BTRFS_I(inode)->root;
8680 struct btrfs_key ins;
8681 u64 cur_offset = start;
8685 bool own_trans = true;
8689 while (num_bytes > 0) {
8691 trans = btrfs_start_transaction(root, 3);
8692 if (IS_ERR(trans)) {
8693 ret = PTR_ERR(trans);
8698 cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
8699 cur_bytes = max(cur_bytes, min_size);
8700 ret = btrfs_reserve_extent(root, cur_bytes, min_size, 0,
8701 *alloc_hint, &ins, 1);
8704 btrfs_end_transaction(trans, root);
8708 ret = insert_reserved_file_extent(trans, inode,
8709 cur_offset, ins.objectid,
8710 ins.offset, ins.offset,
8711 ins.offset, 0, 0, 0,
8712 BTRFS_FILE_EXTENT_PREALLOC);
8714 btrfs_free_reserved_extent(root, ins.objectid,
8716 btrfs_abort_transaction(trans, root, ret);
8718 btrfs_end_transaction(trans, root);
8721 btrfs_drop_extent_cache(inode, cur_offset,
8722 cur_offset + ins.offset -1, 0);
8724 em = alloc_extent_map();
8726 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
8727 &BTRFS_I(inode)->runtime_flags);
8731 em->start = cur_offset;
8732 em->orig_start = cur_offset;
8733 em->len = ins.offset;
8734 em->block_start = ins.objectid;
8735 em->block_len = ins.offset;
8736 em->orig_block_len = ins.offset;
8737 em->ram_bytes = ins.offset;
8738 em->bdev = root->fs_info->fs_devices->latest_bdev;
8739 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
8740 em->generation = trans->transid;
8743 write_lock(&em_tree->lock);
8744 ret = add_extent_mapping(em_tree, em, 1);
8745 write_unlock(&em_tree->lock);
8748 btrfs_drop_extent_cache(inode, cur_offset,
8749 cur_offset + ins.offset - 1,
8752 free_extent_map(em);
8754 num_bytes -= ins.offset;
8755 cur_offset += ins.offset;
8756 *alloc_hint = ins.objectid + ins.offset;
8758 inode_inc_iversion(inode);
8759 inode->i_ctime = CURRENT_TIME;
8760 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
8761 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
8762 (actual_len > inode->i_size) &&
8763 (cur_offset > inode->i_size)) {
8764 if (cur_offset > actual_len)
8765 i_size = actual_len;
8767 i_size = cur_offset;
8768 i_size_write(inode, i_size);
8769 btrfs_ordered_update_i_size(inode, i_size, NULL);
8772 ret = btrfs_update_inode(trans, root, inode);
8775 btrfs_abort_transaction(trans, root, ret);
8777 btrfs_end_transaction(trans, root);
8782 btrfs_end_transaction(trans, root);
8787 int btrfs_prealloc_file_range(struct inode *inode, int mode,
8788 u64 start, u64 num_bytes, u64 min_size,
8789 loff_t actual_len, u64 *alloc_hint)
8791 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8792 min_size, actual_len, alloc_hint,
8796 int btrfs_prealloc_file_range_trans(struct inode *inode,
8797 struct btrfs_trans_handle *trans, int mode,
8798 u64 start, u64 num_bytes, u64 min_size,
8799 loff_t actual_len, u64 *alloc_hint)
8801 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8802 min_size, actual_len, alloc_hint, trans);
8805 static int btrfs_set_page_dirty(struct page *page)
8807 return __set_page_dirty_nobuffers(page);
8810 static int btrfs_permission(struct inode *inode, int mask)
8812 struct btrfs_root *root = BTRFS_I(inode)->root;
8813 umode_t mode = inode->i_mode;
8815 if (mask & MAY_WRITE &&
8816 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
8817 if (btrfs_root_readonly(root))
8819 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
8822 return generic_permission(inode, mask);
8825 static const struct inode_operations btrfs_dir_inode_operations = {
8826 .getattr = btrfs_getattr,
8827 .lookup = btrfs_lookup,
8828 .create = btrfs_create,
8829 .unlink = btrfs_unlink,
8831 .mkdir = btrfs_mkdir,
8832 .rmdir = btrfs_rmdir,
8833 .rename = btrfs_rename,
8834 .symlink = btrfs_symlink,
8835 .setattr = btrfs_setattr,
8836 .mknod = btrfs_mknod,
8837 .setxattr = btrfs_setxattr,
8838 .getxattr = btrfs_getxattr,
8839 .listxattr = btrfs_listxattr,
8840 .removexattr = btrfs_removexattr,
8841 .permission = btrfs_permission,
8842 .get_acl = btrfs_get_acl,
8843 .update_time = btrfs_update_time,
8845 static const struct inode_operations btrfs_dir_ro_inode_operations = {
8846 .lookup = btrfs_lookup,
8847 .permission = btrfs_permission,
8848 .get_acl = btrfs_get_acl,
8849 .update_time = btrfs_update_time,
8852 static const struct file_operations btrfs_dir_file_operations = {
8853 .llseek = generic_file_llseek,
8854 .read = generic_read_dir,
8855 .iterate = btrfs_real_readdir,
8856 .unlocked_ioctl = btrfs_ioctl,
8857 #ifdef CONFIG_COMPAT
8858 .compat_ioctl = btrfs_ioctl,
8860 .release = btrfs_release_file,
8861 .fsync = btrfs_sync_file,
8864 static struct extent_io_ops btrfs_extent_io_ops = {
8865 .fill_delalloc = run_delalloc_range,
8866 .submit_bio_hook = btrfs_submit_bio_hook,
8867 .merge_bio_hook = btrfs_merge_bio_hook,
8868 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
8869 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
8870 .writepage_start_hook = btrfs_writepage_start_hook,
8871 .set_bit_hook = btrfs_set_bit_hook,
8872 .clear_bit_hook = btrfs_clear_bit_hook,
8873 .merge_extent_hook = btrfs_merge_extent_hook,
8874 .split_extent_hook = btrfs_split_extent_hook,
8878 * btrfs doesn't support the bmap operation because swapfiles
8879 * use bmap to make a mapping of extents in the file. They assume
8880 * these extents won't change over the life of the file and they
8881 * use the bmap result to do IO directly to the drive.
8883 * the btrfs bmap call would return logical addresses that aren't
8884 * suitable for IO and they also will change frequently as COW
8885 * operations happen. So, swapfile + btrfs == corruption.
8887 * For now we're avoiding this by dropping bmap.
8889 static const struct address_space_operations btrfs_aops = {
8890 .readpage = btrfs_readpage,
8891 .writepage = btrfs_writepage,
8892 .writepages = btrfs_writepages,
8893 .readpages = btrfs_readpages,
8894 .direct_IO = btrfs_direct_IO,
8895 .invalidatepage = btrfs_invalidatepage,
8896 .releasepage = btrfs_releasepage,
8897 .set_page_dirty = btrfs_set_page_dirty,
8898 .error_remove_page = generic_error_remove_page,
8901 static const struct address_space_operations btrfs_symlink_aops = {
8902 .readpage = btrfs_readpage,
8903 .writepage = btrfs_writepage,
8904 .invalidatepage = btrfs_invalidatepage,
8905 .releasepage = btrfs_releasepage,
8908 static const struct inode_operations btrfs_file_inode_operations = {
8909 .getattr = btrfs_getattr,
8910 .setattr = btrfs_setattr,
8911 .setxattr = btrfs_setxattr,
8912 .getxattr = btrfs_getxattr,
8913 .listxattr = btrfs_listxattr,
8914 .removexattr = btrfs_removexattr,
8915 .permission = btrfs_permission,
8916 .fiemap = btrfs_fiemap,
8917 .get_acl = btrfs_get_acl,
8918 .update_time = btrfs_update_time,
8920 static const struct inode_operations btrfs_special_inode_operations = {
8921 .getattr = btrfs_getattr,
8922 .setattr = btrfs_setattr,
8923 .permission = btrfs_permission,
8924 .setxattr = btrfs_setxattr,
8925 .getxattr = btrfs_getxattr,
8926 .listxattr = btrfs_listxattr,
8927 .removexattr = btrfs_removexattr,
8928 .get_acl = btrfs_get_acl,
8929 .update_time = btrfs_update_time,
8931 static const struct inode_operations btrfs_symlink_inode_operations = {
8932 .readlink = generic_readlink,
8933 .follow_link = page_follow_link_light,
8934 .put_link = page_put_link,
8935 .getattr = btrfs_getattr,
8936 .setattr = btrfs_setattr,
8937 .permission = btrfs_permission,
8938 .setxattr = btrfs_setxattr,
8939 .getxattr = btrfs_getxattr,
8940 .listxattr = btrfs_listxattr,
8941 .removexattr = btrfs_removexattr,
8942 .get_acl = btrfs_get_acl,
8943 .update_time = btrfs_update_time,
8946 const struct dentry_operations btrfs_dentry_operations = {
8947 .d_delete = btrfs_dentry_delete,
8948 .d_release = btrfs_dentry_release,