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>
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"
61 struct btrfs_iget_args {
63 struct btrfs_root *root;
66 static const struct inode_operations btrfs_dir_inode_operations;
67 static const struct inode_operations btrfs_symlink_inode_operations;
68 static const struct inode_operations btrfs_dir_ro_inode_operations;
69 static const struct inode_operations btrfs_special_inode_operations;
70 static const struct inode_operations btrfs_file_inode_operations;
71 static const struct address_space_operations btrfs_aops;
72 static const struct address_space_operations btrfs_symlink_aops;
73 static const struct file_operations btrfs_dir_file_operations;
74 static struct extent_io_ops btrfs_extent_io_ops;
76 static struct kmem_cache *btrfs_inode_cachep;
77 static struct kmem_cache *btrfs_delalloc_work_cachep;
78 struct kmem_cache *btrfs_trans_handle_cachep;
79 struct kmem_cache *btrfs_transaction_cachep;
80 struct kmem_cache *btrfs_path_cachep;
81 struct kmem_cache *btrfs_free_space_cachep;
84 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
85 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
86 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
87 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
88 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
89 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
90 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
91 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
94 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
95 static int btrfs_truncate(struct inode *inode);
96 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
97 static noinline int cow_file_range(struct inode *inode,
98 struct page *locked_page,
99 u64 start, u64 end, int *page_started,
100 unsigned long *nr_written, int unlock);
101 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
102 u64 len, u64 orig_start,
103 u64 block_start, u64 block_len,
104 u64 orig_block_len, u64 ram_bytes,
107 static int btrfs_dirty_inode(struct inode *inode);
109 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
110 struct inode *inode, struct inode *dir,
111 const struct qstr *qstr)
115 err = btrfs_init_acl(trans, inode, dir);
117 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
122 * this does all the hard work for inserting an inline extent into
123 * the btree. The caller should have done a btrfs_drop_extents so that
124 * no overlapping inline items exist in the btree
126 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
127 struct btrfs_root *root, struct inode *inode,
128 u64 start, size_t size, size_t compressed_size,
130 struct page **compressed_pages)
132 struct btrfs_key key;
133 struct btrfs_path *path;
134 struct extent_buffer *leaf;
135 struct page *page = NULL;
138 struct btrfs_file_extent_item *ei;
141 size_t cur_size = size;
143 unsigned long offset;
145 if (compressed_size && compressed_pages)
146 cur_size = compressed_size;
148 path = btrfs_alloc_path();
152 path->leave_spinning = 1;
154 key.objectid = btrfs_ino(inode);
156 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
157 datasize = btrfs_file_extent_calc_inline_size(cur_size);
159 inode_add_bytes(inode, size);
160 ret = btrfs_insert_empty_item(trans, root, path, &key,
166 leaf = path->nodes[0];
167 ei = btrfs_item_ptr(leaf, path->slots[0],
168 struct btrfs_file_extent_item);
169 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
170 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
171 btrfs_set_file_extent_encryption(leaf, ei, 0);
172 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
173 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
174 ptr = btrfs_file_extent_inline_start(ei);
176 if (compress_type != BTRFS_COMPRESS_NONE) {
179 while (compressed_size > 0) {
180 cpage = compressed_pages[i];
181 cur_size = min_t(unsigned long, compressed_size,
184 kaddr = kmap_atomic(cpage);
185 write_extent_buffer(leaf, kaddr, ptr, cur_size);
186 kunmap_atomic(kaddr);
190 compressed_size -= cur_size;
192 btrfs_set_file_extent_compression(leaf, ei,
195 page = find_get_page(inode->i_mapping,
196 start >> PAGE_CACHE_SHIFT);
197 btrfs_set_file_extent_compression(leaf, ei, 0);
198 kaddr = kmap_atomic(page);
199 offset = start & (PAGE_CACHE_SIZE - 1);
200 write_extent_buffer(leaf, kaddr + offset, ptr, size);
201 kunmap_atomic(kaddr);
202 page_cache_release(page);
204 btrfs_mark_buffer_dirty(leaf);
205 btrfs_free_path(path);
208 * we're an inline extent, so nobody can
209 * extend the file past i_size without locking
210 * a page we already have locked.
212 * We must do any isize and inode updates
213 * before we unlock the pages. Otherwise we
214 * could end up racing with unlink.
216 BTRFS_I(inode)->disk_i_size = inode->i_size;
217 ret = btrfs_update_inode(trans, root, inode);
221 btrfs_free_path(path);
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_trans_handle *trans,
232 struct btrfs_root *root,
233 struct inode *inode, u64 start, u64 end,
234 size_t compressed_size, int compress_type,
235 struct page **compressed_pages)
237 u64 isize = i_size_read(inode);
238 u64 actual_end = min(end + 1, isize);
239 u64 inline_len = actual_end - start;
240 u64 aligned_end = ALIGN(end, root->sectorsize);
241 u64 data_len = inline_len;
245 data_len = compressed_size;
248 actual_end >= PAGE_CACHE_SIZE ||
249 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
251 (actual_end & (root->sectorsize - 1)) == 0) ||
253 data_len > root->fs_info->max_inline) {
257 ret = btrfs_drop_extents(trans, root, inode, start, aligned_end, 1);
261 if (isize > actual_end)
262 inline_len = min_t(u64, isize, actual_end);
263 ret = insert_inline_extent(trans, root, inode, start,
264 inline_len, compressed_size,
265 compress_type, compressed_pages);
266 if (ret && ret != -ENOSPC) {
267 btrfs_abort_transaction(trans, root, ret);
269 } else if (ret == -ENOSPC) {
273 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
274 btrfs_delalloc_release_metadata(inode, end + 1 - start);
275 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
279 struct async_extent {
284 unsigned long nr_pages;
286 struct list_head list;
291 struct btrfs_root *root;
292 struct page *locked_page;
295 struct list_head extents;
296 struct btrfs_work work;
299 static noinline int add_async_extent(struct async_cow *cow,
300 u64 start, u64 ram_size,
303 unsigned long nr_pages,
306 struct async_extent *async_extent;
308 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
309 BUG_ON(!async_extent); /* -ENOMEM */
310 async_extent->start = start;
311 async_extent->ram_size = ram_size;
312 async_extent->compressed_size = compressed_size;
313 async_extent->pages = pages;
314 async_extent->nr_pages = nr_pages;
315 async_extent->compress_type = compress_type;
316 list_add_tail(&async_extent->list, &cow->extents);
321 * we create compressed extents in two phases. The first
322 * phase compresses a range of pages that have already been
323 * locked (both pages and state bits are locked).
325 * This is done inside an ordered work queue, and the compression
326 * is spread across many cpus. The actual IO submission is step
327 * two, and the ordered work queue takes care of making sure that
328 * happens in the same order things were put onto the queue by
329 * writepages and friends.
331 * If this code finds it can't get good compression, it puts an
332 * entry onto the work queue to write the uncompressed bytes. This
333 * makes sure that both compressed inodes and uncompressed inodes
334 * are written in the same order that the flusher thread sent them
337 static noinline int compress_file_range(struct inode *inode,
338 struct page *locked_page,
340 struct async_cow *async_cow,
343 struct btrfs_root *root = BTRFS_I(inode)->root;
344 struct btrfs_trans_handle *trans;
346 u64 blocksize = root->sectorsize;
348 u64 isize = i_size_read(inode);
350 struct page **pages = NULL;
351 unsigned long nr_pages;
352 unsigned long nr_pages_ret = 0;
353 unsigned long total_compressed = 0;
354 unsigned long total_in = 0;
355 unsigned long max_compressed = 128 * 1024;
356 unsigned long max_uncompressed = 128 * 1024;
359 int compress_type = root->fs_info->compress_type;
362 /* if this is a small write inside eof, kick off a defrag */
363 if ((end - start + 1) < 16 * 1024 &&
364 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
365 btrfs_add_inode_defrag(NULL, inode);
367 actual_end = min_t(u64, isize, end + 1);
370 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
371 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
374 * we don't want to send crud past the end of i_size through
375 * compression, that's just a waste of CPU time. So, if the
376 * end of the file is before the start of our current
377 * requested range of bytes, we bail out to the uncompressed
378 * cleanup code that can deal with all of this.
380 * It isn't really the fastest way to fix things, but this is a
381 * very uncommon corner.
383 if (actual_end <= start)
384 goto cleanup_and_bail_uncompressed;
386 total_compressed = actual_end - start;
388 /* we want to make sure that amount of ram required to uncompress
389 * an extent is reasonable, so we limit the total size in ram
390 * of a compressed extent to 128k. This is a crucial number
391 * because it also controls how easily we can spread reads across
392 * cpus for decompression.
394 * We also want to make sure the amount of IO required to do
395 * a random read is reasonably small, so we limit the size of
396 * a compressed extent to 128k.
398 total_compressed = min(total_compressed, max_uncompressed);
399 num_bytes = ALIGN(end - start + 1, blocksize);
400 num_bytes = max(blocksize, num_bytes);
405 * we do compression for mount -o compress and when the
406 * inode has not been flagged as nocompress. This flag can
407 * change at any time if we discover bad compression ratios.
409 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
410 (btrfs_test_opt(root, COMPRESS) ||
411 (BTRFS_I(inode)->force_compress) ||
412 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
414 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
416 /* just bail out to the uncompressed code */
420 if (BTRFS_I(inode)->force_compress)
421 compress_type = BTRFS_I(inode)->force_compress;
424 * we need to call clear_page_dirty_for_io on each
425 * page in the range. Otherwise applications with the file
426 * mmap'd can wander in and change the page contents while
427 * we are compressing them.
429 * If the compression fails for any reason, we set the pages
430 * dirty again later on.
432 extent_range_clear_dirty_for_io(inode, start, end);
434 ret = btrfs_compress_pages(compress_type,
435 inode->i_mapping, start,
436 total_compressed, pages,
437 nr_pages, &nr_pages_ret,
443 unsigned long offset = total_compressed &
444 (PAGE_CACHE_SIZE - 1);
445 struct page *page = pages[nr_pages_ret - 1];
448 /* zero the tail end of the last page, we might be
449 * sending it down to disk
452 kaddr = kmap_atomic(page);
453 memset(kaddr + offset, 0,
454 PAGE_CACHE_SIZE - offset);
455 kunmap_atomic(kaddr);
462 trans = btrfs_join_transaction(root);
464 ret = PTR_ERR(trans);
466 goto cleanup_and_out;
468 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
470 /* lets try to make an inline extent */
471 if (ret || total_in < (actual_end - start)) {
472 /* we didn't compress the entire range, try
473 * to make an uncompressed inline extent.
475 ret = cow_file_range_inline(trans, root, inode,
476 start, end, 0, 0, NULL);
478 /* try making a compressed inline extent */
479 ret = cow_file_range_inline(trans, root, inode,
482 compress_type, pages);
486 * inline extent creation worked or returned error,
487 * we don't need to create any more async work items.
488 * Unlock and free up our temp pages.
490 extent_clear_unlock_delalloc(inode,
491 &BTRFS_I(inode)->io_tree,
493 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
494 EXTENT_CLEAR_DELALLOC |
495 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
497 btrfs_end_transaction(trans, root);
500 btrfs_end_transaction(trans, root);
505 * we aren't doing an inline extent round the compressed size
506 * up to a block size boundary so the allocator does sane
509 total_compressed = ALIGN(total_compressed, blocksize);
512 * one last check to make sure the compression is really a
513 * win, compare the page count read with the blocks on disk
515 total_in = ALIGN(total_in, PAGE_CACHE_SIZE);
516 if (total_compressed >= total_in) {
519 num_bytes = total_in;
522 if (!will_compress && pages) {
524 * the compression code ran but failed to make things smaller,
525 * free any pages it allocated and our page pointer array
527 for (i = 0; i < nr_pages_ret; i++) {
528 WARN_ON(pages[i]->mapping);
529 page_cache_release(pages[i]);
533 total_compressed = 0;
536 /* flag the file so we don't compress in the future */
537 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
538 !(BTRFS_I(inode)->force_compress)) {
539 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
545 /* the async work queues will take care of doing actual
546 * allocation on disk for these compressed pages,
547 * and will submit them to the elevator.
549 add_async_extent(async_cow, start, num_bytes,
550 total_compressed, pages, nr_pages_ret,
553 if (start + num_bytes < end) {
560 cleanup_and_bail_uncompressed:
562 * No compression, but we still need to write the pages in
563 * the file we've been given so far. redirty the locked
564 * page if it corresponds to our extent and set things up
565 * for the async work queue to run cow_file_range to do
566 * the normal delalloc dance
568 if (page_offset(locked_page) >= start &&
569 page_offset(locked_page) <= end) {
570 __set_page_dirty_nobuffers(locked_page);
571 /* unlocked later on in the async handlers */
574 extent_range_redirty_for_io(inode, start, end);
575 add_async_extent(async_cow, start, end - start + 1,
576 0, NULL, 0, BTRFS_COMPRESS_NONE);
584 for (i = 0; i < nr_pages_ret; i++) {
585 WARN_ON(pages[i]->mapping);
586 page_cache_release(pages[i]);
593 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
595 EXTENT_CLEAR_UNLOCK_PAGE |
597 EXTENT_CLEAR_DELALLOC |
598 EXTENT_SET_WRITEBACK |
599 EXTENT_END_WRITEBACK);
600 if (!trans || IS_ERR(trans))
601 btrfs_error(root->fs_info, ret, "Failed to join transaction");
603 btrfs_abort_transaction(trans, root, ret);
608 * phase two of compressed writeback. This is the ordered portion
609 * of the code, which only gets called in the order the work was
610 * queued. We walk all the async extents created by compress_file_range
611 * and send them down to the disk.
613 static noinline int submit_compressed_extents(struct inode *inode,
614 struct async_cow *async_cow)
616 struct async_extent *async_extent;
618 struct btrfs_trans_handle *trans;
619 struct btrfs_key ins;
620 struct extent_map *em;
621 struct btrfs_root *root = BTRFS_I(inode)->root;
622 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
623 struct extent_io_tree *io_tree;
626 if (list_empty(&async_cow->extents))
630 while (!list_empty(&async_cow->extents)) {
631 async_extent = list_entry(async_cow->extents.next,
632 struct async_extent, list);
633 list_del(&async_extent->list);
635 io_tree = &BTRFS_I(inode)->io_tree;
638 /* did the compression code fall back to uncompressed IO? */
639 if (!async_extent->pages) {
640 int page_started = 0;
641 unsigned long nr_written = 0;
643 lock_extent(io_tree, async_extent->start,
644 async_extent->start +
645 async_extent->ram_size - 1);
647 /* allocate blocks */
648 ret = cow_file_range(inode, async_cow->locked_page,
650 async_extent->start +
651 async_extent->ram_size - 1,
652 &page_started, &nr_written, 0);
657 * if page_started, cow_file_range inserted an
658 * inline extent and took care of all the unlocking
659 * and IO for us. Otherwise, we need to submit
660 * all those pages down to the drive.
662 if (!page_started && !ret)
663 extent_write_locked_range(io_tree,
664 inode, async_extent->start,
665 async_extent->start +
666 async_extent->ram_size - 1,
670 unlock_page(async_cow->locked_page);
676 lock_extent(io_tree, async_extent->start,
677 async_extent->start + async_extent->ram_size - 1);
679 trans = btrfs_join_transaction(root);
681 ret = PTR_ERR(trans);
683 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
684 ret = btrfs_reserve_extent(trans, root,
685 async_extent->compressed_size,
686 async_extent->compressed_size,
687 0, alloc_hint, &ins, 1);
688 if (ret && ret != -ENOSPC)
689 btrfs_abort_transaction(trans, root, ret);
690 btrfs_end_transaction(trans, root);
696 for (i = 0; i < async_extent->nr_pages; i++) {
697 WARN_ON(async_extent->pages[i]->mapping);
698 page_cache_release(async_extent->pages[i]);
700 kfree(async_extent->pages);
701 async_extent->nr_pages = 0;
702 async_extent->pages = NULL;
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();
719 goto out_free_reserve;
720 em->start = async_extent->start;
721 em->len = async_extent->ram_size;
722 em->orig_start = em->start;
723 em->mod_start = em->start;
724 em->mod_len = em->len;
726 em->block_start = ins.objectid;
727 em->block_len = ins.offset;
728 em->orig_block_len = ins.offset;
729 em->ram_bytes = async_extent->ram_size;
730 em->bdev = root->fs_info->fs_devices->latest_bdev;
731 em->compress_type = async_extent->compress_type;
732 set_bit(EXTENT_FLAG_PINNED, &em->flags);
733 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
737 write_lock(&em_tree->lock);
738 ret = add_extent_mapping(em_tree, em, 1);
739 write_unlock(&em_tree->lock);
740 if (ret != -EEXIST) {
744 btrfs_drop_extent_cache(inode, async_extent->start,
745 async_extent->start +
746 async_extent->ram_size - 1, 0);
750 goto out_free_reserve;
752 ret = btrfs_add_ordered_extent_compress(inode,
755 async_extent->ram_size,
757 BTRFS_ORDERED_COMPRESSED,
758 async_extent->compress_type);
760 goto out_free_reserve;
763 * clear dirty, set writeback and unlock the pages.
765 extent_clear_unlock_delalloc(inode,
766 &BTRFS_I(inode)->io_tree,
768 async_extent->start +
769 async_extent->ram_size - 1,
770 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
771 EXTENT_CLEAR_UNLOCK |
772 EXTENT_CLEAR_DELALLOC |
773 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
775 ret = btrfs_submit_compressed_write(inode,
777 async_extent->ram_size,
779 ins.offset, async_extent->pages,
780 async_extent->nr_pages);
781 alloc_hint = ins.objectid + ins.offset;
791 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
793 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
795 async_extent->start +
796 async_extent->ram_size - 1,
797 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
798 EXTENT_CLEAR_UNLOCK |
799 EXTENT_CLEAR_DELALLOC |
801 EXTENT_SET_WRITEBACK |
802 EXTENT_END_WRITEBACK);
807 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
810 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
811 struct extent_map *em;
814 read_lock(&em_tree->lock);
815 em = search_extent_mapping(em_tree, start, num_bytes);
818 * if block start isn't an actual block number then find the
819 * first block in this inode and use that as a hint. If that
820 * block is also bogus then just don't worry about it.
822 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
824 em = search_extent_mapping(em_tree, 0, 0);
825 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
826 alloc_hint = em->block_start;
830 alloc_hint = em->block_start;
834 read_unlock(&em_tree->lock);
840 * when extent_io.c finds a delayed allocation range in the file,
841 * the call backs end up in this code. The basic idea is to
842 * allocate extents on disk for the range, and create ordered data structs
843 * in ram to track those extents.
845 * locked_page is the page that writepage had locked already. We use
846 * it to make sure we don't do extra locks or unlocks.
848 * *page_started is set to one if we unlock locked_page and do everything
849 * required to start IO on it. It may be clean and already done with
852 static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
854 struct btrfs_root *root,
855 struct page *locked_page,
856 u64 start, u64 end, int *page_started,
857 unsigned long *nr_written,
862 unsigned long ram_size;
865 u64 blocksize = root->sectorsize;
866 struct btrfs_key ins;
867 struct extent_map *em;
868 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
871 BUG_ON(btrfs_is_free_space_inode(inode));
873 num_bytes = ALIGN(end - start + 1, blocksize);
874 num_bytes = max(blocksize, num_bytes);
875 disk_num_bytes = num_bytes;
877 /* if this is a small write inside eof, kick off defrag */
878 if (num_bytes < 64 * 1024 &&
879 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
880 btrfs_add_inode_defrag(trans, inode);
883 /* lets try to make an inline extent */
884 ret = cow_file_range_inline(trans, root, inode,
885 start, end, 0, 0, NULL);
887 extent_clear_unlock_delalloc(inode,
888 &BTRFS_I(inode)->io_tree,
890 EXTENT_CLEAR_UNLOCK_PAGE |
891 EXTENT_CLEAR_UNLOCK |
892 EXTENT_CLEAR_DELALLOC |
894 EXTENT_SET_WRITEBACK |
895 EXTENT_END_WRITEBACK);
897 *nr_written = *nr_written +
898 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
901 } else if (ret < 0) {
902 btrfs_abort_transaction(trans, root, ret);
907 BUG_ON(disk_num_bytes >
908 btrfs_super_total_bytes(root->fs_info->super_copy));
910 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
911 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
913 while (disk_num_bytes > 0) {
916 cur_alloc_size = disk_num_bytes;
917 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
918 root->sectorsize, 0, alloc_hint,
921 btrfs_abort_transaction(trans, root, ret);
925 em = alloc_extent_map();
929 em->orig_start = em->start;
930 ram_size = ins.offset;
931 em->len = ins.offset;
932 em->mod_start = em->start;
933 em->mod_len = em->len;
935 em->block_start = ins.objectid;
936 em->block_len = ins.offset;
937 em->orig_block_len = ins.offset;
938 em->ram_bytes = ram_size;
939 em->bdev = root->fs_info->fs_devices->latest_bdev;
940 set_bit(EXTENT_FLAG_PINNED, &em->flags);
944 write_lock(&em_tree->lock);
945 ret = add_extent_mapping(em_tree, em, 1);
946 write_unlock(&em_tree->lock);
947 if (ret != -EEXIST) {
951 btrfs_drop_extent_cache(inode, start,
952 start + ram_size - 1, 0);
957 cur_alloc_size = ins.offset;
958 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
959 ram_size, cur_alloc_size, 0);
963 if (root->root_key.objectid ==
964 BTRFS_DATA_RELOC_TREE_OBJECTID) {
965 ret = btrfs_reloc_clone_csums(inode, start,
968 btrfs_abort_transaction(trans, root, ret);
973 if (disk_num_bytes < cur_alloc_size)
976 /* we're not doing compressed IO, don't unlock the first
977 * page (which the caller expects to stay locked), don't
978 * clear any dirty bits and don't set any writeback bits
980 * Do set the Private2 bit so we know this page was properly
981 * setup for writepage
983 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
984 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
987 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
988 start, start + ram_size - 1,
990 disk_num_bytes -= cur_alloc_size;
991 num_bytes -= cur_alloc_size;
992 alloc_hint = ins.objectid + ins.offset;
993 start += cur_alloc_size;
999 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
1001 extent_clear_unlock_delalloc(inode,
1002 &BTRFS_I(inode)->io_tree,
1003 start, end, locked_page,
1004 EXTENT_CLEAR_UNLOCK_PAGE |
1005 EXTENT_CLEAR_UNLOCK |
1006 EXTENT_CLEAR_DELALLOC |
1007 EXTENT_CLEAR_DIRTY |
1008 EXTENT_SET_WRITEBACK |
1009 EXTENT_END_WRITEBACK);
1014 static noinline int cow_file_range(struct inode *inode,
1015 struct page *locked_page,
1016 u64 start, u64 end, int *page_started,
1017 unsigned long *nr_written,
1020 struct btrfs_trans_handle *trans;
1021 struct btrfs_root *root = BTRFS_I(inode)->root;
1024 trans = btrfs_join_transaction(root);
1025 if (IS_ERR(trans)) {
1026 extent_clear_unlock_delalloc(inode,
1027 &BTRFS_I(inode)->io_tree,
1028 start, end, locked_page,
1029 EXTENT_CLEAR_UNLOCK_PAGE |
1030 EXTENT_CLEAR_UNLOCK |
1031 EXTENT_CLEAR_DELALLOC |
1032 EXTENT_CLEAR_DIRTY |
1033 EXTENT_SET_WRITEBACK |
1034 EXTENT_END_WRITEBACK);
1035 return PTR_ERR(trans);
1037 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1039 ret = __cow_file_range(trans, inode, root, locked_page, start, end,
1040 page_started, nr_written, unlock);
1042 btrfs_end_transaction(trans, root);
1048 * work queue call back to started compression on a file and pages
1050 static noinline void async_cow_start(struct btrfs_work *work)
1052 struct async_cow *async_cow;
1054 async_cow = container_of(work, struct async_cow, work);
1056 compress_file_range(async_cow->inode, async_cow->locked_page,
1057 async_cow->start, async_cow->end, async_cow,
1059 if (num_added == 0) {
1060 btrfs_add_delayed_iput(async_cow->inode);
1061 async_cow->inode = NULL;
1066 * work queue call back to submit previously compressed pages
1068 static noinline void async_cow_submit(struct btrfs_work *work)
1070 struct async_cow *async_cow;
1071 struct btrfs_root *root;
1072 unsigned long nr_pages;
1074 async_cow = container_of(work, struct async_cow, work);
1076 root = async_cow->root;
1077 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
1080 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) <
1082 waitqueue_active(&root->fs_info->async_submit_wait))
1083 wake_up(&root->fs_info->async_submit_wait);
1085 if (async_cow->inode)
1086 submit_compressed_extents(async_cow->inode, async_cow);
1089 static noinline void async_cow_free(struct btrfs_work *work)
1091 struct async_cow *async_cow;
1092 async_cow = container_of(work, struct async_cow, work);
1093 if (async_cow->inode)
1094 btrfs_add_delayed_iput(async_cow->inode);
1098 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1099 u64 start, u64 end, int *page_started,
1100 unsigned long *nr_written)
1102 struct async_cow *async_cow;
1103 struct btrfs_root *root = BTRFS_I(inode)->root;
1104 unsigned long nr_pages;
1106 int limit = 10 * 1024 * 1024;
1108 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1109 1, 0, NULL, GFP_NOFS);
1110 while (start < end) {
1111 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1112 BUG_ON(!async_cow); /* -ENOMEM */
1113 async_cow->inode = igrab(inode);
1114 async_cow->root = root;
1115 async_cow->locked_page = locked_page;
1116 async_cow->start = start;
1118 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
1121 cur_end = min(end, start + 512 * 1024 - 1);
1123 async_cow->end = cur_end;
1124 INIT_LIST_HEAD(&async_cow->extents);
1126 async_cow->work.func = async_cow_start;
1127 async_cow->work.ordered_func = async_cow_submit;
1128 async_cow->work.ordered_free = async_cow_free;
1129 async_cow->work.flags = 0;
1131 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1133 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1135 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1138 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1139 wait_event(root->fs_info->async_submit_wait,
1140 (atomic_read(&root->fs_info->async_delalloc_pages) <
1144 while (atomic_read(&root->fs_info->async_submit_draining) &&
1145 atomic_read(&root->fs_info->async_delalloc_pages)) {
1146 wait_event(root->fs_info->async_submit_wait,
1147 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1151 *nr_written += nr_pages;
1152 start = cur_end + 1;
1158 static noinline int csum_exist_in_range(struct btrfs_root *root,
1159 u64 bytenr, u64 num_bytes)
1162 struct btrfs_ordered_sum *sums;
1165 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1166 bytenr + num_bytes - 1, &list, 0);
1167 if (ret == 0 && list_empty(&list))
1170 while (!list_empty(&list)) {
1171 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1172 list_del(&sums->list);
1179 * when nowcow writeback call back. This checks for snapshots or COW copies
1180 * of the extents that exist in the file, and COWs the file as required.
1182 * If no cow copies or snapshots exist, we write directly to the existing
1185 static noinline int run_delalloc_nocow(struct inode *inode,
1186 struct page *locked_page,
1187 u64 start, u64 end, int *page_started, int force,
1188 unsigned long *nr_written)
1190 struct btrfs_root *root = BTRFS_I(inode)->root;
1191 struct btrfs_trans_handle *trans;
1192 struct extent_buffer *leaf;
1193 struct btrfs_path *path;
1194 struct btrfs_file_extent_item *fi;
1195 struct btrfs_key found_key;
1210 u64 ino = btrfs_ino(inode);
1212 path = btrfs_alloc_path();
1214 extent_clear_unlock_delalloc(inode,
1215 &BTRFS_I(inode)->io_tree,
1216 start, end, locked_page,
1217 EXTENT_CLEAR_UNLOCK_PAGE |
1218 EXTENT_CLEAR_UNLOCK |
1219 EXTENT_CLEAR_DELALLOC |
1220 EXTENT_CLEAR_DIRTY |
1221 EXTENT_SET_WRITEBACK |
1222 EXTENT_END_WRITEBACK);
1226 nolock = btrfs_is_free_space_inode(inode);
1229 trans = btrfs_join_transaction_nolock(root);
1231 trans = btrfs_join_transaction(root);
1233 if (IS_ERR(trans)) {
1234 extent_clear_unlock_delalloc(inode,
1235 &BTRFS_I(inode)->io_tree,
1236 start, end, locked_page,
1237 EXTENT_CLEAR_UNLOCK_PAGE |
1238 EXTENT_CLEAR_UNLOCK |
1239 EXTENT_CLEAR_DELALLOC |
1240 EXTENT_CLEAR_DIRTY |
1241 EXTENT_SET_WRITEBACK |
1242 EXTENT_END_WRITEBACK);
1243 btrfs_free_path(path);
1244 return PTR_ERR(trans);
1247 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1249 cow_start = (u64)-1;
1252 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1255 btrfs_abort_transaction(trans, root, ret);
1258 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1259 leaf = path->nodes[0];
1260 btrfs_item_key_to_cpu(leaf, &found_key,
1261 path->slots[0] - 1);
1262 if (found_key.objectid == ino &&
1263 found_key.type == BTRFS_EXTENT_DATA_KEY)
1268 leaf = path->nodes[0];
1269 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1270 ret = btrfs_next_leaf(root, path);
1272 btrfs_abort_transaction(trans, root, ret);
1277 leaf = path->nodes[0];
1283 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1285 if (found_key.objectid > ino ||
1286 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1287 found_key.offset > end)
1290 if (found_key.offset > cur_offset) {
1291 extent_end = found_key.offset;
1296 fi = btrfs_item_ptr(leaf, path->slots[0],
1297 struct btrfs_file_extent_item);
1298 extent_type = btrfs_file_extent_type(leaf, fi);
1300 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1301 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1302 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1303 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1304 extent_offset = btrfs_file_extent_offset(leaf, fi);
1305 extent_end = found_key.offset +
1306 btrfs_file_extent_num_bytes(leaf, fi);
1308 btrfs_file_extent_disk_num_bytes(leaf, fi);
1309 if (extent_end <= start) {
1313 if (disk_bytenr == 0)
1315 if (btrfs_file_extent_compression(leaf, fi) ||
1316 btrfs_file_extent_encryption(leaf, fi) ||
1317 btrfs_file_extent_other_encoding(leaf, fi))
1319 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1321 if (btrfs_extent_readonly(root, disk_bytenr))
1323 if (btrfs_cross_ref_exist(trans, root, ino,
1325 extent_offset, disk_bytenr))
1327 disk_bytenr += extent_offset;
1328 disk_bytenr += cur_offset - found_key.offset;
1329 num_bytes = min(end + 1, extent_end) - cur_offset;
1331 * force cow if csum exists in the range.
1332 * this ensure that csum for a given extent are
1333 * either valid or do not exist.
1335 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1338 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1339 extent_end = found_key.offset +
1340 btrfs_file_extent_inline_len(leaf, fi);
1341 extent_end = ALIGN(extent_end, root->sectorsize);
1346 if (extent_end <= start) {
1351 if (cow_start == (u64)-1)
1352 cow_start = cur_offset;
1353 cur_offset = extent_end;
1354 if (cur_offset > end)
1360 btrfs_release_path(path);
1361 if (cow_start != (u64)-1) {
1362 ret = __cow_file_range(trans, inode, root, locked_page,
1363 cow_start, found_key.offset - 1,
1364 page_started, nr_written, 1);
1366 btrfs_abort_transaction(trans, root, ret);
1369 cow_start = (u64)-1;
1372 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1373 struct extent_map *em;
1374 struct extent_map_tree *em_tree;
1375 em_tree = &BTRFS_I(inode)->extent_tree;
1376 em = alloc_extent_map();
1377 BUG_ON(!em); /* -ENOMEM */
1378 em->start = cur_offset;
1379 em->orig_start = found_key.offset - extent_offset;
1380 em->len = num_bytes;
1381 em->block_len = num_bytes;
1382 em->block_start = disk_bytenr;
1383 em->orig_block_len = disk_num_bytes;
1384 em->ram_bytes = ram_bytes;
1385 em->bdev = root->fs_info->fs_devices->latest_bdev;
1386 em->mod_start = em->start;
1387 em->mod_len = em->len;
1388 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1389 set_bit(EXTENT_FLAG_FILLING, &em->flags);
1390 em->generation = -1;
1392 write_lock(&em_tree->lock);
1393 ret = add_extent_mapping(em_tree, em, 1);
1394 write_unlock(&em_tree->lock);
1395 if (ret != -EEXIST) {
1396 free_extent_map(em);
1399 btrfs_drop_extent_cache(inode, em->start,
1400 em->start + em->len - 1, 0);
1402 type = BTRFS_ORDERED_PREALLOC;
1404 type = BTRFS_ORDERED_NOCOW;
1407 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1408 num_bytes, num_bytes, type);
1409 BUG_ON(ret); /* -ENOMEM */
1411 if (root->root_key.objectid ==
1412 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1413 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1416 btrfs_abort_transaction(trans, root, ret);
1421 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1422 cur_offset, cur_offset + num_bytes - 1,
1423 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1424 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1425 EXTENT_SET_PRIVATE2);
1426 cur_offset = extent_end;
1427 if (cur_offset > end)
1430 btrfs_release_path(path);
1432 if (cur_offset <= end && cow_start == (u64)-1) {
1433 cow_start = cur_offset;
1437 if (cow_start != (u64)-1) {
1438 ret = __cow_file_range(trans, inode, root, locked_page,
1440 page_started, nr_written, 1);
1442 btrfs_abort_transaction(trans, root, ret);
1448 err = btrfs_end_transaction(trans, root);
1452 if (ret && cur_offset < end)
1453 extent_clear_unlock_delalloc(inode,
1454 &BTRFS_I(inode)->io_tree,
1455 cur_offset, end, locked_page,
1456 EXTENT_CLEAR_UNLOCK_PAGE |
1457 EXTENT_CLEAR_UNLOCK |
1458 EXTENT_CLEAR_DELALLOC |
1459 EXTENT_CLEAR_DIRTY |
1460 EXTENT_SET_WRITEBACK |
1461 EXTENT_END_WRITEBACK);
1463 btrfs_free_path(path);
1468 * extent_io.c call back to do delayed allocation processing
1470 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1471 u64 start, u64 end, int *page_started,
1472 unsigned long *nr_written)
1475 struct btrfs_root *root = BTRFS_I(inode)->root;
1477 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
1478 ret = run_delalloc_nocow(inode, locked_page, start, end,
1479 page_started, 1, nr_written);
1480 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
1481 ret = run_delalloc_nocow(inode, locked_page, start, end,
1482 page_started, 0, nr_written);
1483 } else if (!btrfs_test_opt(root, COMPRESS) &&
1484 !(BTRFS_I(inode)->force_compress) &&
1485 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
1486 ret = cow_file_range(inode, locked_page, start, end,
1487 page_started, nr_written, 1);
1489 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1490 &BTRFS_I(inode)->runtime_flags);
1491 ret = cow_file_range_async(inode, locked_page, start, end,
1492 page_started, nr_written);
1497 static void btrfs_split_extent_hook(struct inode *inode,
1498 struct extent_state *orig, u64 split)
1500 /* not delalloc, ignore it */
1501 if (!(orig->state & EXTENT_DELALLOC))
1504 spin_lock(&BTRFS_I(inode)->lock);
1505 BTRFS_I(inode)->outstanding_extents++;
1506 spin_unlock(&BTRFS_I(inode)->lock);
1510 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1511 * extents so we can keep track of new extents that are just merged onto old
1512 * extents, such as when we are doing sequential writes, so we can properly
1513 * account for the metadata space we'll need.
1515 static void btrfs_merge_extent_hook(struct inode *inode,
1516 struct extent_state *new,
1517 struct extent_state *other)
1519 /* not delalloc, ignore it */
1520 if (!(other->state & EXTENT_DELALLOC))
1523 spin_lock(&BTRFS_I(inode)->lock);
1524 BTRFS_I(inode)->outstanding_extents--;
1525 spin_unlock(&BTRFS_I(inode)->lock);
1529 * extent_io.c set_bit_hook, used to track delayed allocation
1530 * bytes in this file, and to maintain the list of inodes that
1531 * have pending delalloc work to be done.
1533 static void btrfs_set_bit_hook(struct inode *inode,
1534 struct extent_state *state, unsigned long *bits)
1538 * set_bit and clear bit hooks normally require _irqsave/restore
1539 * but in this case, we are only testing for the DELALLOC
1540 * bit, which is only set or cleared with irqs on
1542 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1543 struct btrfs_root *root = BTRFS_I(inode)->root;
1544 u64 len = state->end + 1 - state->start;
1545 bool do_list = !btrfs_is_free_space_inode(inode);
1547 if (*bits & EXTENT_FIRST_DELALLOC) {
1548 *bits &= ~EXTENT_FIRST_DELALLOC;
1550 spin_lock(&BTRFS_I(inode)->lock);
1551 BTRFS_I(inode)->outstanding_extents++;
1552 spin_unlock(&BTRFS_I(inode)->lock);
1555 __percpu_counter_add(&root->fs_info->delalloc_bytes, len,
1556 root->fs_info->delalloc_batch);
1557 spin_lock(&BTRFS_I(inode)->lock);
1558 BTRFS_I(inode)->delalloc_bytes += len;
1559 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1560 &BTRFS_I(inode)->runtime_flags)) {
1561 spin_lock(&root->fs_info->delalloc_lock);
1562 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1563 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1564 &root->fs_info->delalloc_inodes);
1565 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1566 &BTRFS_I(inode)->runtime_flags);
1568 spin_unlock(&root->fs_info->delalloc_lock);
1570 spin_unlock(&BTRFS_I(inode)->lock);
1575 * extent_io.c clear_bit_hook, see set_bit_hook for why
1577 static void btrfs_clear_bit_hook(struct inode *inode,
1578 struct extent_state *state,
1579 unsigned long *bits)
1582 * set_bit and clear bit hooks normally require _irqsave/restore
1583 * but in this case, we are only testing for the DELALLOC
1584 * bit, which is only set or cleared with irqs on
1586 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1587 struct btrfs_root *root = BTRFS_I(inode)->root;
1588 u64 len = state->end + 1 - state->start;
1589 bool do_list = !btrfs_is_free_space_inode(inode);
1591 if (*bits & EXTENT_FIRST_DELALLOC) {
1592 *bits &= ~EXTENT_FIRST_DELALLOC;
1593 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1594 spin_lock(&BTRFS_I(inode)->lock);
1595 BTRFS_I(inode)->outstanding_extents--;
1596 spin_unlock(&BTRFS_I(inode)->lock);
1599 if (*bits & EXTENT_DO_ACCOUNTING)
1600 btrfs_delalloc_release_metadata(inode, len);
1602 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1604 btrfs_free_reserved_data_space(inode, len);
1606 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len,
1607 root->fs_info->delalloc_batch);
1608 spin_lock(&BTRFS_I(inode)->lock);
1609 BTRFS_I(inode)->delalloc_bytes -= len;
1610 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1611 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1612 &BTRFS_I(inode)->runtime_flags)) {
1613 spin_lock(&root->fs_info->delalloc_lock);
1614 if (!list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1615 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1616 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1617 &BTRFS_I(inode)->runtime_flags);
1619 spin_unlock(&root->fs_info->delalloc_lock);
1621 spin_unlock(&BTRFS_I(inode)->lock);
1626 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1627 * we don't create bios that span stripes or chunks
1629 int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
1630 size_t size, struct bio *bio,
1631 unsigned long bio_flags)
1633 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1634 u64 logical = (u64)bio->bi_sector << 9;
1639 if (bio_flags & EXTENT_BIO_COMPRESSED)
1642 length = bio->bi_size;
1643 map_length = length;
1644 ret = btrfs_map_block(root->fs_info, rw, logical,
1645 &map_length, NULL, 0);
1646 /* Will always return 0 with map_multi == NULL */
1648 if (map_length < length + size)
1654 * in order to insert checksums into the metadata in large chunks,
1655 * we wait until bio submission time. All the pages in the bio are
1656 * checksummed and sums are attached onto the ordered extent record.
1658 * At IO completion time the cums attached on the ordered extent record
1659 * are inserted into the btree
1661 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1662 struct bio *bio, int mirror_num,
1663 unsigned long bio_flags,
1666 struct btrfs_root *root = BTRFS_I(inode)->root;
1669 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1670 BUG_ON(ret); /* -ENOMEM */
1675 * in order to insert checksums into the metadata in large chunks,
1676 * we wait until bio submission time. All the pages in the bio are
1677 * checksummed and sums are attached onto the ordered extent record.
1679 * At IO completion time the cums attached on the ordered extent record
1680 * are inserted into the btree
1682 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1683 int mirror_num, unsigned long bio_flags,
1686 struct btrfs_root *root = BTRFS_I(inode)->root;
1689 ret = btrfs_map_bio(root, rw, bio, mirror_num, 1);
1691 bio_endio(bio, ret);
1696 * extent_io.c submission hook. This does the right thing for csum calculation
1697 * on write, or reading the csums from the tree before a read
1699 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1700 int mirror_num, unsigned long bio_flags,
1703 struct btrfs_root *root = BTRFS_I(inode)->root;
1707 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
1709 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1711 if (btrfs_is_free_space_inode(inode))
1714 if (!(rw & REQ_WRITE)) {
1715 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata);
1719 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1720 ret = btrfs_submit_compressed_read(inode, bio,
1724 } else if (!skip_sum) {
1725 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1730 } else if (async && !skip_sum) {
1731 /* csum items have already been cloned */
1732 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1734 /* we're doing a write, do the async checksumming */
1735 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1736 inode, rw, bio, mirror_num,
1737 bio_flags, bio_offset,
1738 __btrfs_submit_bio_start,
1739 __btrfs_submit_bio_done);
1741 } else if (!skip_sum) {
1742 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1748 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0);
1752 bio_endio(bio, ret);
1757 * given a list of ordered sums record them in the inode. This happens
1758 * at IO completion time based on sums calculated at bio submission time.
1760 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1761 struct inode *inode, u64 file_offset,
1762 struct list_head *list)
1764 struct btrfs_ordered_sum *sum;
1766 list_for_each_entry(sum, list, list) {
1767 trans->adding_csums = 1;
1768 btrfs_csum_file_blocks(trans,
1769 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1770 trans->adding_csums = 0;
1775 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1776 struct extent_state **cached_state)
1778 WARN_ON((end & (PAGE_CACHE_SIZE - 1)) == 0);
1779 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1780 cached_state, GFP_NOFS);
1783 /* see btrfs_writepage_start_hook for details on why this is required */
1784 struct btrfs_writepage_fixup {
1786 struct btrfs_work work;
1789 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1791 struct btrfs_writepage_fixup *fixup;
1792 struct btrfs_ordered_extent *ordered;
1793 struct extent_state *cached_state = NULL;
1795 struct inode *inode;
1800 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1804 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1805 ClearPageChecked(page);
1809 inode = page->mapping->host;
1810 page_start = page_offset(page);
1811 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1813 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1816 /* already ordered? We're done */
1817 if (PagePrivate2(page))
1820 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1822 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1823 page_end, &cached_state, GFP_NOFS);
1825 btrfs_start_ordered_extent(inode, ordered, 1);
1826 btrfs_put_ordered_extent(ordered);
1830 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
1832 mapping_set_error(page->mapping, ret);
1833 end_extent_writepage(page, ret, page_start, page_end);
1834 ClearPageChecked(page);
1838 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1839 ClearPageChecked(page);
1840 set_page_dirty(page);
1842 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1843 &cached_state, GFP_NOFS);
1846 page_cache_release(page);
1851 * There are a few paths in the higher layers of the kernel that directly
1852 * set the page dirty bit without asking the filesystem if it is a
1853 * good idea. This causes problems because we want to make sure COW
1854 * properly happens and the data=ordered rules are followed.
1856 * In our case any range that doesn't have the ORDERED bit set
1857 * hasn't been properly setup for IO. We kick off an async process
1858 * to fix it up. The async helper will wait for ordered extents, set
1859 * the delalloc bit and make it safe to write the page.
1861 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1863 struct inode *inode = page->mapping->host;
1864 struct btrfs_writepage_fixup *fixup;
1865 struct btrfs_root *root = BTRFS_I(inode)->root;
1867 /* this page is properly in the ordered list */
1868 if (TestClearPagePrivate2(page))
1871 if (PageChecked(page))
1874 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1878 SetPageChecked(page);
1879 page_cache_get(page);
1880 fixup->work.func = btrfs_writepage_fixup_worker;
1882 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1886 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1887 struct inode *inode, u64 file_pos,
1888 u64 disk_bytenr, u64 disk_num_bytes,
1889 u64 num_bytes, u64 ram_bytes,
1890 u8 compression, u8 encryption,
1891 u16 other_encoding, int extent_type)
1893 struct btrfs_root *root = BTRFS_I(inode)->root;
1894 struct btrfs_file_extent_item *fi;
1895 struct btrfs_path *path;
1896 struct extent_buffer *leaf;
1897 struct btrfs_key ins;
1900 path = btrfs_alloc_path();
1904 path->leave_spinning = 1;
1907 * we may be replacing one extent in the tree with another.
1908 * The new extent is pinned in the extent map, and we don't want
1909 * to drop it from the cache until it is completely in the btree.
1911 * So, tell btrfs_drop_extents to leave this extent in the cache.
1912 * the caller is expected to unpin it and allow it to be merged
1915 ret = btrfs_drop_extents(trans, root, inode, file_pos,
1916 file_pos + num_bytes, 0);
1920 ins.objectid = btrfs_ino(inode);
1921 ins.offset = file_pos;
1922 ins.type = BTRFS_EXTENT_DATA_KEY;
1923 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1926 leaf = path->nodes[0];
1927 fi = btrfs_item_ptr(leaf, path->slots[0],
1928 struct btrfs_file_extent_item);
1929 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1930 btrfs_set_file_extent_type(leaf, fi, extent_type);
1931 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1932 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1933 btrfs_set_file_extent_offset(leaf, fi, 0);
1934 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1935 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1936 btrfs_set_file_extent_compression(leaf, fi, compression);
1937 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1938 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1940 btrfs_mark_buffer_dirty(leaf);
1941 btrfs_release_path(path);
1943 inode_add_bytes(inode, num_bytes);
1945 ins.objectid = disk_bytenr;
1946 ins.offset = disk_num_bytes;
1947 ins.type = BTRFS_EXTENT_ITEM_KEY;
1948 ret = btrfs_alloc_reserved_file_extent(trans, root,
1949 root->root_key.objectid,
1950 btrfs_ino(inode), file_pos, &ins);
1952 btrfs_free_path(path);
1957 /* snapshot-aware defrag */
1958 struct sa_defrag_extent_backref {
1959 struct rb_node node;
1960 struct old_sa_defrag_extent *old;
1969 struct old_sa_defrag_extent {
1970 struct list_head list;
1971 struct new_sa_defrag_extent *new;
1980 struct new_sa_defrag_extent {
1981 struct rb_root root;
1982 struct list_head head;
1983 struct btrfs_path *path;
1984 struct inode *inode;
1992 static int backref_comp(struct sa_defrag_extent_backref *b1,
1993 struct sa_defrag_extent_backref *b2)
1995 if (b1->root_id < b2->root_id)
1997 else if (b1->root_id > b2->root_id)
2000 if (b1->inum < b2->inum)
2002 else if (b1->inum > b2->inum)
2005 if (b1->file_pos < b2->file_pos)
2007 else if (b1->file_pos > b2->file_pos)
2011 * [------------------------------] ===> (a range of space)
2012 * |<--->| |<---->| =============> (fs/file tree A)
2013 * |<---------------------------->| ===> (fs/file tree B)
2015 * A range of space can refer to two file extents in one tree while
2016 * refer to only one file extent in another tree.
2018 * So we may process a disk offset more than one time(two extents in A)
2019 * and locate at the same extent(one extent in B), then insert two same
2020 * backrefs(both refer to the extent in B).
2025 static void backref_insert(struct rb_root *root,
2026 struct sa_defrag_extent_backref *backref)
2028 struct rb_node **p = &root->rb_node;
2029 struct rb_node *parent = NULL;
2030 struct sa_defrag_extent_backref *entry;
2035 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
2037 ret = backref_comp(backref, entry);
2041 p = &(*p)->rb_right;
2044 rb_link_node(&backref->node, parent, p);
2045 rb_insert_color(&backref->node, root);
2049 * Note the backref might has changed, and in this case we just return 0.
2051 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2054 struct btrfs_file_extent_item *extent;
2055 struct btrfs_fs_info *fs_info;
2056 struct old_sa_defrag_extent *old = ctx;
2057 struct new_sa_defrag_extent *new = old->new;
2058 struct btrfs_path *path = new->path;
2059 struct btrfs_key key;
2060 struct btrfs_root *root;
2061 struct sa_defrag_extent_backref *backref;
2062 struct extent_buffer *leaf;
2063 struct inode *inode = new->inode;
2069 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2070 inum == btrfs_ino(inode))
2073 key.objectid = root_id;
2074 key.type = BTRFS_ROOT_ITEM_KEY;
2075 key.offset = (u64)-1;
2077 fs_info = BTRFS_I(inode)->root->fs_info;
2078 root = btrfs_read_fs_root_no_name(fs_info, &key);
2080 if (PTR_ERR(root) == -ENOENT)
2083 pr_debug("inum=%llu, offset=%llu, root_id=%llu\n",
2084 inum, offset, root_id);
2085 return PTR_ERR(root);
2088 key.objectid = inum;
2089 key.type = BTRFS_EXTENT_DATA_KEY;
2090 if (offset > (u64)-1 << 32)
2093 key.offset = offset;
2095 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2104 leaf = path->nodes[0];
2105 slot = path->slots[0];
2107 if (slot >= btrfs_header_nritems(leaf)) {
2108 ret = btrfs_next_leaf(root, path);
2111 } else if (ret > 0) {
2120 btrfs_item_key_to_cpu(leaf, &key, slot);
2122 if (key.objectid > inum)
2125 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2128 extent = btrfs_item_ptr(leaf, slot,
2129 struct btrfs_file_extent_item);
2131 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2134 extent_offset = btrfs_file_extent_offset(leaf, extent);
2135 if (key.offset - extent_offset != offset)
2138 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2139 if (extent_offset >= old->extent_offset + old->offset +
2140 old->len || extent_offset + num_bytes <=
2141 old->extent_offset + old->offset)
2147 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2153 backref->root_id = root_id;
2154 backref->inum = inum;
2155 backref->file_pos = offset + extent_offset;
2156 backref->num_bytes = num_bytes;
2157 backref->extent_offset = extent_offset;
2158 backref->generation = btrfs_file_extent_generation(leaf, extent);
2160 backref_insert(&new->root, backref);
2163 btrfs_release_path(path);
2168 static noinline bool record_extent_backrefs(struct btrfs_path *path,
2169 struct new_sa_defrag_extent *new)
2171 struct btrfs_fs_info *fs_info = BTRFS_I(new->inode)->root->fs_info;
2172 struct old_sa_defrag_extent *old, *tmp;
2177 list_for_each_entry_safe(old, tmp, &new->head, list) {
2178 ret = iterate_inodes_from_logical(old->bytenr, fs_info,
2179 path, record_one_backref,
2181 BUG_ON(ret < 0 && ret != -ENOENT);
2183 /* no backref to be processed for this extent */
2185 list_del(&old->list);
2190 if (list_empty(&new->head))
2196 static int relink_is_mergable(struct extent_buffer *leaf,
2197 struct btrfs_file_extent_item *fi,
2200 if (btrfs_file_extent_disk_bytenr(leaf, fi) != disk_bytenr)
2203 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2206 if (btrfs_file_extent_compression(leaf, fi) ||
2207 btrfs_file_extent_encryption(leaf, fi) ||
2208 btrfs_file_extent_other_encoding(leaf, fi))
2215 * Note the backref might has changed, and in this case we just return 0.
2217 static noinline int relink_extent_backref(struct btrfs_path *path,
2218 struct sa_defrag_extent_backref *prev,
2219 struct sa_defrag_extent_backref *backref)
2221 struct btrfs_file_extent_item *extent;
2222 struct btrfs_file_extent_item *item;
2223 struct btrfs_ordered_extent *ordered;
2224 struct btrfs_trans_handle *trans;
2225 struct btrfs_fs_info *fs_info;
2226 struct btrfs_root *root;
2227 struct btrfs_key key;
2228 struct extent_buffer *leaf;
2229 struct old_sa_defrag_extent *old = backref->old;
2230 struct new_sa_defrag_extent *new = old->new;
2231 struct inode *src_inode = new->inode;
2232 struct inode *inode;
2233 struct extent_state *cached = NULL;
2242 if (prev && prev->root_id == backref->root_id &&
2243 prev->inum == backref->inum &&
2244 prev->file_pos + prev->num_bytes == backref->file_pos)
2247 /* step 1: get root */
2248 key.objectid = backref->root_id;
2249 key.type = BTRFS_ROOT_ITEM_KEY;
2250 key.offset = (u64)-1;
2252 fs_info = BTRFS_I(src_inode)->root->fs_info;
2253 index = srcu_read_lock(&fs_info->subvol_srcu);
2255 root = btrfs_read_fs_root_no_name(fs_info, &key);
2257 srcu_read_unlock(&fs_info->subvol_srcu, index);
2258 if (PTR_ERR(root) == -ENOENT)
2260 return PTR_ERR(root);
2262 if (btrfs_root_refs(&root->root_item) == 0) {
2263 srcu_read_unlock(&fs_info->subvol_srcu, index);
2264 /* parse ENOENT to 0 */
2268 /* step 2: get inode */
2269 key.objectid = backref->inum;
2270 key.type = BTRFS_INODE_ITEM_KEY;
2273 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2274 if (IS_ERR(inode)) {
2275 srcu_read_unlock(&fs_info->subvol_srcu, index);
2279 srcu_read_unlock(&fs_info->subvol_srcu, index);
2281 /* step 3: relink backref */
2282 lock_start = backref->file_pos;
2283 lock_end = backref->file_pos + backref->num_bytes - 1;
2284 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2287 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2289 btrfs_put_ordered_extent(ordered);
2293 trans = btrfs_join_transaction(root);
2294 if (IS_ERR(trans)) {
2295 ret = PTR_ERR(trans);
2299 key.objectid = backref->inum;
2300 key.type = BTRFS_EXTENT_DATA_KEY;
2301 key.offset = backref->file_pos;
2303 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2306 } else if (ret > 0) {
2311 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2312 struct btrfs_file_extent_item);
2314 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2315 backref->generation)
2318 btrfs_release_path(path);
2320 start = backref->file_pos;
2321 if (backref->extent_offset < old->extent_offset + old->offset)
2322 start += old->extent_offset + old->offset -
2323 backref->extent_offset;
2325 len = min(backref->extent_offset + backref->num_bytes,
2326 old->extent_offset + old->offset + old->len);
2327 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2329 ret = btrfs_drop_extents(trans, root, inode, start,
2334 key.objectid = btrfs_ino(inode);
2335 key.type = BTRFS_EXTENT_DATA_KEY;
2338 path->leave_spinning = 1;
2340 struct btrfs_file_extent_item *fi;
2342 struct btrfs_key found_key;
2344 ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
2349 leaf = path->nodes[0];
2350 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2352 fi = btrfs_item_ptr(leaf, path->slots[0],
2353 struct btrfs_file_extent_item);
2354 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2356 if (relink_is_mergable(leaf, fi, new->bytenr) &&
2357 extent_len + found_key.offset == start) {
2358 btrfs_set_file_extent_num_bytes(leaf, fi,
2360 btrfs_mark_buffer_dirty(leaf);
2361 inode_add_bytes(inode, len);
2367 btrfs_release_path(path);
2372 ret = btrfs_insert_empty_item(trans, root, path, &key,
2375 btrfs_abort_transaction(trans, root, ret);
2379 leaf = path->nodes[0];
2380 item = btrfs_item_ptr(leaf, path->slots[0],
2381 struct btrfs_file_extent_item);
2382 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2383 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2384 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2385 btrfs_set_file_extent_num_bytes(leaf, item, len);
2386 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2387 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2388 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2389 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2390 btrfs_set_file_extent_encryption(leaf, item, 0);
2391 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2393 btrfs_mark_buffer_dirty(leaf);
2394 inode_add_bytes(inode, len);
2395 btrfs_release_path(path);
2397 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2399 backref->root_id, backref->inum,
2400 new->file_pos, 0); /* start - extent_offset */
2402 btrfs_abort_transaction(trans, root, ret);
2408 btrfs_release_path(path);
2409 path->leave_spinning = 0;
2410 btrfs_end_transaction(trans, root);
2412 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2418 static void relink_file_extents(struct new_sa_defrag_extent *new)
2420 struct btrfs_path *path;
2421 struct old_sa_defrag_extent *old, *tmp;
2422 struct sa_defrag_extent_backref *backref;
2423 struct sa_defrag_extent_backref *prev = NULL;
2424 struct inode *inode;
2425 struct btrfs_root *root;
2426 struct rb_node *node;
2430 root = BTRFS_I(inode)->root;
2432 path = btrfs_alloc_path();
2436 if (!record_extent_backrefs(path, new)) {
2437 btrfs_free_path(path);
2440 btrfs_release_path(path);
2443 node = rb_first(&new->root);
2446 rb_erase(node, &new->root);
2448 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2450 ret = relink_extent_backref(path, prev, backref);
2463 btrfs_free_path(path);
2465 list_for_each_entry_safe(old, tmp, &new->head, list) {
2466 list_del(&old->list);
2470 atomic_dec(&root->fs_info->defrag_running);
2471 wake_up(&root->fs_info->transaction_wait);
2476 static struct new_sa_defrag_extent *
2477 record_old_file_extents(struct inode *inode,
2478 struct btrfs_ordered_extent *ordered)
2480 struct btrfs_root *root = BTRFS_I(inode)->root;
2481 struct btrfs_path *path;
2482 struct btrfs_key key;
2483 struct old_sa_defrag_extent *old, *tmp;
2484 struct new_sa_defrag_extent *new;
2487 new = kmalloc(sizeof(*new), GFP_NOFS);
2492 new->file_pos = ordered->file_offset;
2493 new->len = ordered->len;
2494 new->bytenr = ordered->start;
2495 new->disk_len = ordered->disk_len;
2496 new->compress_type = ordered->compress_type;
2497 new->root = RB_ROOT;
2498 INIT_LIST_HEAD(&new->head);
2500 path = btrfs_alloc_path();
2504 key.objectid = btrfs_ino(inode);
2505 key.type = BTRFS_EXTENT_DATA_KEY;
2506 key.offset = new->file_pos;
2508 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2511 if (ret > 0 && path->slots[0] > 0)
2514 /* find out all the old extents for the file range */
2516 struct btrfs_file_extent_item *extent;
2517 struct extent_buffer *l;
2526 slot = path->slots[0];
2528 if (slot >= btrfs_header_nritems(l)) {
2529 ret = btrfs_next_leaf(root, path);
2537 btrfs_item_key_to_cpu(l, &key, slot);
2539 if (key.objectid != btrfs_ino(inode))
2541 if (key.type != BTRFS_EXTENT_DATA_KEY)
2543 if (key.offset >= new->file_pos + new->len)
2546 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2548 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2549 if (key.offset + num_bytes < new->file_pos)
2552 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2556 extent_offset = btrfs_file_extent_offset(l, extent);
2558 old = kmalloc(sizeof(*old), GFP_NOFS);
2562 offset = max(new->file_pos, key.offset);
2563 end = min(new->file_pos + new->len, key.offset + num_bytes);
2565 old->bytenr = disk_bytenr;
2566 old->extent_offset = extent_offset;
2567 old->offset = offset - key.offset;
2568 old->len = end - offset;
2571 list_add_tail(&old->list, &new->head);
2577 btrfs_free_path(path);
2578 atomic_inc(&root->fs_info->defrag_running);
2583 list_for_each_entry_safe(old, tmp, &new->head, list) {
2584 list_del(&old->list);
2588 btrfs_free_path(path);
2595 * helper function for btrfs_finish_ordered_io, this
2596 * just reads in some of the csum leaves to prime them into ram
2597 * before we start the transaction. It limits the amount of btree
2598 * reads required while inside the transaction.
2600 /* as ordered data IO finishes, this gets called so we can finish
2601 * an ordered extent if the range of bytes in the file it covers are
2604 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2606 struct inode *inode = ordered_extent->inode;
2607 struct btrfs_root *root = BTRFS_I(inode)->root;
2608 struct btrfs_trans_handle *trans = NULL;
2609 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2610 struct extent_state *cached_state = NULL;
2611 struct new_sa_defrag_extent *new = NULL;
2612 int compress_type = 0;
2616 nolock = btrfs_is_free_space_inode(inode);
2618 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2623 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2624 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2625 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2627 trans = btrfs_join_transaction_nolock(root);
2629 trans = btrfs_join_transaction(root);
2630 if (IS_ERR(trans)) {
2631 ret = PTR_ERR(trans);
2635 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2636 ret = btrfs_update_inode_fallback(trans, root, inode);
2637 if (ret) /* -ENOMEM or corruption */
2638 btrfs_abort_transaction(trans, root, ret);
2642 lock_extent_bits(io_tree, ordered_extent->file_offset,
2643 ordered_extent->file_offset + ordered_extent->len - 1,
2646 ret = test_range_bit(io_tree, ordered_extent->file_offset,
2647 ordered_extent->file_offset + ordered_extent->len - 1,
2648 EXTENT_DEFRAG, 1, cached_state);
2650 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2651 if (last_snapshot >= BTRFS_I(inode)->generation)
2652 /* the inode is shared */
2653 new = record_old_file_extents(inode, ordered_extent);
2655 clear_extent_bit(io_tree, ordered_extent->file_offset,
2656 ordered_extent->file_offset + ordered_extent->len - 1,
2657 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS);
2661 trans = btrfs_join_transaction_nolock(root);
2663 trans = btrfs_join_transaction(root);
2664 if (IS_ERR(trans)) {
2665 ret = PTR_ERR(trans);
2669 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
2671 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
2672 compress_type = ordered_extent->compress_type;
2673 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2674 BUG_ON(compress_type);
2675 ret = btrfs_mark_extent_written(trans, inode,
2676 ordered_extent->file_offset,
2677 ordered_extent->file_offset +
2678 ordered_extent->len);
2680 BUG_ON(root == root->fs_info->tree_root);
2681 ret = insert_reserved_file_extent(trans, inode,
2682 ordered_extent->file_offset,
2683 ordered_extent->start,
2684 ordered_extent->disk_len,
2685 ordered_extent->len,
2686 ordered_extent->len,
2687 compress_type, 0, 0,
2688 BTRFS_FILE_EXTENT_REG);
2690 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2691 ordered_extent->file_offset, ordered_extent->len,
2694 btrfs_abort_transaction(trans, root, ret);
2698 add_pending_csums(trans, inode, ordered_extent->file_offset,
2699 &ordered_extent->list);
2701 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2702 ret = btrfs_update_inode_fallback(trans, root, inode);
2703 if (ret) { /* -ENOMEM or corruption */
2704 btrfs_abort_transaction(trans, root, ret);
2709 unlock_extent_cached(io_tree, ordered_extent->file_offset,
2710 ordered_extent->file_offset +
2711 ordered_extent->len - 1, &cached_state, GFP_NOFS);
2713 if (root != root->fs_info->tree_root)
2714 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
2716 btrfs_end_transaction(trans, root);
2719 clear_extent_uptodate(io_tree, ordered_extent->file_offset,
2720 ordered_extent->file_offset +
2721 ordered_extent->len - 1, NULL, GFP_NOFS);
2724 * If the ordered extent had an IOERR or something else went
2725 * wrong we need to return the space for this ordered extent
2726 * back to the allocator.
2728 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2729 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
2730 btrfs_free_reserved_extent(root, ordered_extent->start,
2731 ordered_extent->disk_len);
2736 * This needs to be done to make sure anybody waiting knows we are done
2737 * updating everything for this ordered extent.
2739 btrfs_remove_ordered_extent(inode, ordered_extent);
2741 /* for snapshot-aware defrag */
2743 relink_file_extents(new);
2746 btrfs_put_ordered_extent(ordered_extent);
2747 /* once for the tree */
2748 btrfs_put_ordered_extent(ordered_extent);
2753 static void finish_ordered_fn(struct btrfs_work *work)
2755 struct btrfs_ordered_extent *ordered_extent;
2756 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2757 btrfs_finish_ordered_io(ordered_extent);
2760 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
2761 struct extent_state *state, int uptodate)
2763 struct inode *inode = page->mapping->host;
2764 struct btrfs_root *root = BTRFS_I(inode)->root;
2765 struct btrfs_ordered_extent *ordered_extent = NULL;
2766 struct btrfs_workers *workers;
2768 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2770 ClearPagePrivate2(page);
2771 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2772 end - start + 1, uptodate))
2775 ordered_extent->work.func = finish_ordered_fn;
2776 ordered_extent->work.flags = 0;
2778 if (btrfs_is_free_space_inode(inode))
2779 workers = &root->fs_info->endio_freespace_worker;
2781 workers = &root->fs_info->endio_write_workers;
2782 btrfs_queue_worker(workers, &ordered_extent->work);
2788 * when reads are done, we need to check csums to verify the data is correct
2789 * if there's a match, we allow the bio to finish. If not, the code in
2790 * extent_io.c will try to find good copies for us.
2792 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
2793 struct extent_state *state, int mirror)
2795 size_t offset = start - page_offset(page);
2796 struct inode *inode = page->mapping->host;
2797 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2799 u64 private = ~(u32)0;
2801 struct btrfs_root *root = BTRFS_I(inode)->root;
2803 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
2804 DEFAULT_RATELIMIT_BURST);
2806 if (PageChecked(page)) {
2807 ClearPageChecked(page);
2811 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
2814 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
2815 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
2816 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
2821 if (state && state->start == start) {
2822 private = state->private;
2825 ret = get_state_private(io_tree, start, &private);
2827 kaddr = kmap_atomic(page);
2831 csum = btrfs_csum_data(kaddr + offset, csum, end - start + 1);
2832 btrfs_csum_final(csum, (char *)&csum);
2833 if (csum != private)
2836 kunmap_atomic(kaddr);
2841 if (__ratelimit(&_rs))
2842 btrfs_info(root->fs_info, "csum failed ino %llu off %llu csum %u private %llu",
2843 (unsigned long long)btrfs_ino(page->mapping->host),
2844 (unsigned long long)start, csum,
2845 (unsigned long long)private);
2846 memset(kaddr + offset, 1, end - start + 1);
2847 flush_dcache_page(page);
2848 kunmap_atomic(kaddr);
2854 struct delayed_iput {
2855 struct list_head list;
2856 struct inode *inode;
2859 /* JDM: If this is fs-wide, why can't we add a pointer to
2860 * btrfs_inode instead and avoid the allocation? */
2861 void btrfs_add_delayed_iput(struct inode *inode)
2863 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2864 struct delayed_iput *delayed;
2866 if (atomic_add_unless(&inode->i_count, -1, 1))
2869 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2870 delayed->inode = inode;
2872 spin_lock(&fs_info->delayed_iput_lock);
2873 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2874 spin_unlock(&fs_info->delayed_iput_lock);
2877 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2880 struct btrfs_fs_info *fs_info = root->fs_info;
2881 struct delayed_iput *delayed;
2884 spin_lock(&fs_info->delayed_iput_lock);
2885 empty = list_empty(&fs_info->delayed_iputs);
2886 spin_unlock(&fs_info->delayed_iput_lock);
2890 spin_lock(&fs_info->delayed_iput_lock);
2891 list_splice_init(&fs_info->delayed_iputs, &list);
2892 spin_unlock(&fs_info->delayed_iput_lock);
2894 while (!list_empty(&list)) {
2895 delayed = list_entry(list.next, struct delayed_iput, list);
2896 list_del(&delayed->list);
2897 iput(delayed->inode);
2903 * This is called in transaction commit time. If there are no orphan
2904 * files in the subvolume, it removes orphan item and frees block_rsv
2907 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2908 struct btrfs_root *root)
2910 struct btrfs_block_rsv *block_rsv;
2913 if (atomic_read(&root->orphan_inodes) ||
2914 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2917 spin_lock(&root->orphan_lock);
2918 if (atomic_read(&root->orphan_inodes)) {
2919 spin_unlock(&root->orphan_lock);
2923 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) {
2924 spin_unlock(&root->orphan_lock);
2928 block_rsv = root->orphan_block_rsv;
2929 root->orphan_block_rsv = NULL;
2930 spin_unlock(&root->orphan_lock);
2932 if (root->orphan_item_inserted &&
2933 btrfs_root_refs(&root->root_item) > 0) {
2934 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2935 root->root_key.objectid);
2937 root->orphan_item_inserted = 0;
2941 WARN_ON(block_rsv->size > 0);
2942 btrfs_free_block_rsv(root, block_rsv);
2947 * This creates an orphan entry for the given inode in case something goes
2948 * wrong in the middle of an unlink/truncate.
2950 * NOTE: caller of this function should reserve 5 units of metadata for
2953 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2955 struct btrfs_root *root = BTRFS_I(inode)->root;
2956 struct btrfs_block_rsv *block_rsv = NULL;
2961 if (!root->orphan_block_rsv) {
2962 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
2967 spin_lock(&root->orphan_lock);
2968 if (!root->orphan_block_rsv) {
2969 root->orphan_block_rsv = block_rsv;
2970 } else if (block_rsv) {
2971 btrfs_free_block_rsv(root, block_rsv);
2975 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
2976 &BTRFS_I(inode)->runtime_flags)) {
2979 * For proper ENOSPC handling, we should do orphan
2980 * cleanup when mounting. But this introduces backward
2981 * compatibility issue.
2983 if (!xchg(&root->orphan_item_inserted, 1))
2989 atomic_inc(&root->orphan_inodes);
2992 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
2993 &BTRFS_I(inode)->runtime_flags))
2995 spin_unlock(&root->orphan_lock);
2997 /* grab metadata reservation from transaction handle */
2999 ret = btrfs_orphan_reserve_metadata(trans, inode);
3000 BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */
3003 /* insert an orphan item to track this unlinked/truncated file */
3005 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
3006 if (ret && ret != -EEXIST) {
3007 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3008 &BTRFS_I(inode)->runtime_flags);
3009 btrfs_abort_transaction(trans, root, ret);
3015 /* insert an orphan item to track subvolume contains orphan files */
3017 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
3018 root->root_key.objectid);
3019 if (ret && ret != -EEXIST) {
3020 btrfs_abort_transaction(trans, root, ret);
3028 * We have done the truncate/delete so we can go ahead and remove the orphan
3029 * item for this particular inode.
3031 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3032 struct inode *inode)
3034 struct btrfs_root *root = BTRFS_I(inode)->root;
3035 int delete_item = 0;
3036 int release_rsv = 0;
3039 spin_lock(&root->orphan_lock);
3040 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3041 &BTRFS_I(inode)->runtime_flags))
3044 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
3045 &BTRFS_I(inode)->runtime_flags))
3047 spin_unlock(&root->orphan_lock);
3049 if (trans && delete_item) {
3050 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
3051 BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */
3055 btrfs_orphan_release_metadata(inode);
3056 atomic_dec(&root->orphan_inodes);
3063 * this cleans up any orphans that may be left on the list from the last use
3066 int btrfs_orphan_cleanup(struct btrfs_root *root)
3068 struct btrfs_path *path;
3069 struct extent_buffer *leaf;
3070 struct btrfs_key key, found_key;
3071 struct btrfs_trans_handle *trans;
3072 struct inode *inode;
3073 u64 last_objectid = 0;
3074 int ret = 0, nr_unlink = 0, nr_truncate = 0;
3076 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3079 path = btrfs_alloc_path();
3086 key.objectid = BTRFS_ORPHAN_OBJECTID;
3087 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
3088 key.offset = (u64)-1;
3091 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3096 * if ret == 0 means we found what we were searching for, which
3097 * is weird, but possible, so only screw with path if we didn't
3098 * find the key and see if we have stuff that matches
3102 if (path->slots[0] == 0)
3107 /* pull out the item */
3108 leaf = path->nodes[0];
3109 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3111 /* make sure the item matches what we want */
3112 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3114 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
3117 /* release the path since we're done with it */
3118 btrfs_release_path(path);
3121 * this is where we are basically btrfs_lookup, without the
3122 * crossing root thing. we store the inode number in the
3123 * offset of the orphan item.
3126 if (found_key.offset == last_objectid) {
3127 btrfs_err(root->fs_info,
3128 "Error removing orphan entry, stopping orphan cleanup");
3133 last_objectid = found_key.offset;
3135 found_key.objectid = found_key.offset;
3136 found_key.type = BTRFS_INODE_ITEM_KEY;
3137 found_key.offset = 0;
3138 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
3139 ret = PTR_RET(inode);
3140 if (ret && ret != -ESTALE)
3143 if (ret == -ESTALE && root == root->fs_info->tree_root) {
3144 struct btrfs_root *dead_root;
3145 struct btrfs_fs_info *fs_info = root->fs_info;
3146 int is_dead_root = 0;
3149 * this is an orphan in the tree root. Currently these
3150 * could come from 2 sources:
3151 * a) a snapshot deletion in progress
3152 * b) a free space cache inode
3153 * We need to distinguish those two, as the snapshot
3154 * orphan must not get deleted.
3155 * find_dead_roots already ran before us, so if this
3156 * is a snapshot deletion, we should find the root
3157 * in the dead_roots list
3159 spin_lock(&fs_info->trans_lock);
3160 list_for_each_entry(dead_root, &fs_info->dead_roots,
3162 if (dead_root->root_key.objectid ==
3163 found_key.objectid) {
3168 spin_unlock(&fs_info->trans_lock);
3170 /* prevent this orphan from being found again */
3171 key.offset = found_key.objectid - 1;
3176 * Inode is already gone but the orphan item is still there,
3177 * kill the orphan item.
3179 if (ret == -ESTALE) {
3180 trans = btrfs_start_transaction(root, 1);
3181 if (IS_ERR(trans)) {
3182 ret = PTR_ERR(trans);
3185 btrfs_debug(root->fs_info, "auto deleting %Lu",
3186 found_key.objectid);
3187 ret = btrfs_del_orphan_item(trans, root,
3188 found_key.objectid);
3189 BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */
3190 btrfs_end_transaction(trans, root);
3195 * add this inode to the orphan list so btrfs_orphan_del does
3196 * the proper thing when we hit it
3198 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
3199 &BTRFS_I(inode)->runtime_flags);
3200 atomic_inc(&root->orphan_inodes);
3202 /* if we have links, this was a truncate, lets do that */
3203 if (inode->i_nlink) {
3204 if (!S_ISREG(inode->i_mode)) {
3211 /* 1 for the orphan item deletion. */
3212 trans = btrfs_start_transaction(root, 1);
3213 if (IS_ERR(trans)) {
3214 ret = PTR_ERR(trans);
3217 ret = btrfs_orphan_add(trans, inode);
3218 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)
3271 u32 nritems = btrfs_header_nritems(leaf);
3272 struct btrfs_key found_key;
3276 while (slot < nritems) {
3277 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3279 /* we found a different objectid, there must not be acls */
3280 if (found_key.objectid != objectid)
3283 /* we found an xattr, assume we've got an acl */
3284 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
3288 * we found a key greater than an xattr key, there can't
3289 * be any acls later on
3291 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3298 * it goes inode, inode backrefs, xattrs, extents,
3299 * so if there are a ton of hard links to an inode there can
3300 * be a lot of backrefs. Don't waste time searching too hard,
3301 * this is just an optimization
3306 /* we hit the end of the leaf before we found an xattr or
3307 * something larger than an xattr. We have to assume the inode
3314 * read an inode from the btree into the in-memory inode
3316 static void btrfs_read_locked_inode(struct inode *inode)
3318 struct btrfs_path *path;
3319 struct extent_buffer *leaf;
3320 struct btrfs_inode_item *inode_item;
3321 struct btrfs_timespec *tspec;
3322 struct btrfs_root *root = BTRFS_I(inode)->root;
3323 struct btrfs_key location;
3327 bool filled = false;
3329 ret = btrfs_fill_inode(inode, &rdev);
3333 path = btrfs_alloc_path();
3337 path->leave_spinning = 1;
3338 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3340 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3344 leaf = path->nodes[0];
3349 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3350 struct btrfs_inode_item);
3351 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3352 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3353 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3354 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3355 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
3357 tspec = btrfs_inode_atime(inode_item);
3358 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3359 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3361 tspec = btrfs_inode_mtime(inode_item);
3362 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3363 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3365 tspec = btrfs_inode_ctime(inode_item);
3366 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
3367 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
3369 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3370 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3371 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3374 * If we were modified in the current generation and evicted from memory
3375 * and then re-read we need to do a full sync since we don't have any
3376 * idea about which extents were modified before we were evicted from
3379 if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
3380 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3381 &BTRFS_I(inode)->runtime_flags);
3383 inode->i_version = btrfs_inode_sequence(leaf, inode_item);
3384 inode->i_generation = BTRFS_I(inode)->generation;
3386 rdev = btrfs_inode_rdev(leaf, inode_item);
3388 BTRFS_I(inode)->index_cnt = (u64)-1;
3389 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3392 * try to precache a NULL acl entry for files that don't have
3393 * any xattrs or acls
3395 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3398 cache_no_acl(inode);
3400 btrfs_free_path(path);
3402 switch (inode->i_mode & S_IFMT) {
3404 inode->i_mapping->a_ops = &btrfs_aops;
3405 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3406 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3407 inode->i_fop = &btrfs_file_operations;
3408 inode->i_op = &btrfs_file_inode_operations;
3411 inode->i_fop = &btrfs_dir_file_operations;
3412 if (root == root->fs_info->tree_root)
3413 inode->i_op = &btrfs_dir_ro_inode_operations;
3415 inode->i_op = &btrfs_dir_inode_operations;
3418 inode->i_op = &btrfs_symlink_inode_operations;
3419 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3420 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3423 inode->i_op = &btrfs_special_inode_operations;
3424 init_special_inode(inode, inode->i_mode, rdev);
3428 btrfs_update_iflags(inode);
3432 btrfs_free_path(path);
3433 make_bad_inode(inode);
3437 * given a leaf and an inode, copy the inode fields into the leaf
3439 static void fill_inode_item(struct btrfs_trans_handle *trans,
3440 struct extent_buffer *leaf,
3441 struct btrfs_inode_item *item,
3442 struct inode *inode)
3444 struct btrfs_map_token token;
3446 btrfs_init_map_token(&token);
3448 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3449 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3450 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3452 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3453 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3455 btrfs_set_token_timespec_sec(leaf, btrfs_inode_atime(item),
3456 inode->i_atime.tv_sec, &token);
3457 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_atime(item),
3458 inode->i_atime.tv_nsec, &token);
3460 btrfs_set_token_timespec_sec(leaf, btrfs_inode_mtime(item),
3461 inode->i_mtime.tv_sec, &token);
3462 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_mtime(item),
3463 inode->i_mtime.tv_nsec, &token);
3465 btrfs_set_token_timespec_sec(leaf, btrfs_inode_ctime(item),
3466 inode->i_ctime.tv_sec, &token);
3467 btrfs_set_token_timespec_nsec(leaf, btrfs_inode_ctime(item),
3468 inode->i_ctime.tv_nsec, &token);
3470 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3472 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3474 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token);
3475 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3476 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3477 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3478 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3482 * copy everything in the in-memory inode into the btree.
3484 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3485 struct btrfs_root *root, struct inode *inode)
3487 struct btrfs_inode_item *inode_item;
3488 struct btrfs_path *path;
3489 struct extent_buffer *leaf;
3492 path = btrfs_alloc_path();
3496 path->leave_spinning = 1;
3497 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3505 btrfs_unlock_up_safe(path, 1);
3506 leaf = path->nodes[0];
3507 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3508 struct btrfs_inode_item);
3510 fill_inode_item(trans, leaf, inode_item, inode);
3511 btrfs_mark_buffer_dirty(leaf);
3512 btrfs_set_inode_last_trans(trans, inode);
3515 btrfs_free_path(path);
3520 * copy everything in the in-memory inode into the btree.
3522 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3523 struct btrfs_root *root, struct inode *inode)
3528 * If the inode is a free space inode, we can deadlock during commit
3529 * if we put it into the delayed code.
3531 * The data relocation inode should also be directly updated
3534 if (!btrfs_is_free_space_inode(inode)
3535 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
3536 btrfs_update_root_times(trans, root);
3538 ret = btrfs_delayed_update_inode(trans, root, inode);
3540 btrfs_set_inode_last_trans(trans, inode);
3544 return btrfs_update_inode_item(trans, root, inode);
3547 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3548 struct btrfs_root *root,
3549 struct inode *inode)
3553 ret = btrfs_update_inode(trans, root, inode);
3555 return btrfs_update_inode_item(trans, root, inode);
3560 * unlink helper that gets used here in inode.c and in the tree logging
3561 * recovery code. It remove a link in a directory with a given name, and
3562 * also drops the back refs in the inode to the directory
3564 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3565 struct btrfs_root *root,
3566 struct inode *dir, struct inode *inode,
3567 const char *name, int name_len)
3569 struct btrfs_path *path;
3571 struct extent_buffer *leaf;
3572 struct btrfs_dir_item *di;
3573 struct btrfs_key key;
3575 u64 ino = btrfs_ino(inode);
3576 u64 dir_ino = btrfs_ino(dir);
3578 path = btrfs_alloc_path();
3584 path->leave_spinning = 1;
3585 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3586 name, name_len, -1);
3595 leaf = path->nodes[0];
3596 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3597 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3600 btrfs_release_path(path);
3602 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3605 btrfs_info(root->fs_info,
3606 "failed to delete reference to %.*s, inode %llu parent %llu",
3608 (unsigned long long)ino, (unsigned long long)dir_ino);
3609 btrfs_abort_transaction(trans, root, ret);
3613 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3615 btrfs_abort_transaction(trans, root, ret);
3619 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
3621 if (ret != 0 && ret != -ENOENT) {
3622 btrfs_abort_transaction(trans, root, ret);
3626 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
3631 btrfs_abort_transaction(trans, root, ret);
3633 btrfs_free_path(path);
3637 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3638 inode_inc_iversion(inode);
3639 inode_inc_iversion(dir);
3640 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3641 ret = btrfs_update_inode(trans, root, dir);
3646 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3647 struct btrfs_root *root,
3648 struct inode *dir, struct inode *inode,
3649 const char *name, int name_len)
3652 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3654 btrfs_drop_nlink(inode);
3655 ret = btrfs_update_inode(trans, root, inode);
3661 /* helper to check if there is any shared block in the path */
3662 static int check_path_shared(struct btrfs_root *root,
3663 struct btrfs_path *path)
3665 struct extent_buffer *eb;
3669 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
3672 if (!path->nodes[level])
3674 eb = path->nodes[level];
3675 if (!btrfs_block_can_be_shared(root, eb))
3677 ret = btrfs_lookup_extent_info(NULL, root, eb->start, level, 1,
3686 * helper to start transaction for unlink and rmdir.
3688 * unlink and rmdir are special in btrfs, they do not always free space.
3689 * so in enospc case, we should make sure they will free space before
3690 * allowing them to use the global metadata reservation.
3692 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
3693 struct dentry *dentry)
3695 struct btrfs_trans_handle *trans;
3696 struct btrfs_root *root = BTRFS_I(dir)->root;
3697 struct btrfs_path *path;
3698 struct btrfs_dir_item *di;
3699 struct inode *inode = dentry->d_inode;
3704 u64 ino = btrfs_ino(inode);
3705 u64 dir_ino = btrfs_ino(dir);
3708 * 1 for the possible orphan item
3709 * 1 for the dir item
3710 * 1 for the dir index
3711 * 1 for the inode ref
3714 trans = btrfs_start_transaction(root, 5);
3715 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
3718 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
3719 return ERR_PTR(-ENOSPC);
3721 /* check if there is someone else holds reference */
3722 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
3723 return ERR_PTR(-ENOSPC);
3725 if (atomic_read(&inode->i_count) > 2)
3726 return ERR_PTR(-ENOSPC);
3728 if (xchg(&root->fs_info->enospc_unlink, 1))
3729 return ERR_PTR(-ENOSPC);
3731 path = btrfs_alloc_path();
3733 root->fs_info->enospc_unlink = 0;
3734 return ERR_PTR(-ENOMEM);
3737 /* 1 for the orphan item */
3738 trans = btrfs_start_transaction(root, 1);
3739 if (IS_ERR(trans)) {
3740 btrfs_free_path(path);
3741 root->fs_info->enospc_unlink = 0;
3745 path->skip_locking = 1;
3746 path->search_commit_root = 1;
3748 ret = btrfs_lookup_inode(trans, root, path,
3749 &BTRFS_I(dir)->location, 0);
3755 if (check_path_shared(root, path))
3760 btrfs_release_path(path);
3762 ret = btrfs_lookup_inode(trans, root, path,
3763 &BTRFS_I(inode)->location, 0);
3769 if (check_path_shared(root, path))
3774 btrfs_release_path(path);
3776 if (ret == 0 && S_ISREG(inode->i_mode)) {
3777 ret = btrfs_lookup_file_extent(trans, root, path,
3783 BUG_ON(ret == 0); /* Corruption */
3784 if (check_path_shared(root, path))
3786 btrfs_release_path(path);
3794 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3795 dentry->d_name.name, dentry->d_name.len, 0);
3801 if (check_path_shared(root, path))
3807 btrfs_release_path(path);
3809 ret = btrfs_get_inode_ref_index(trans, root, path, dentry->d_name.name,
3810 dentry->d_name.len, ino, dir_ino, 0,
3817 if (check_path_shared(root, path))
3820 btrfs_release_path(path);
3823 * This is a commit root search, if we can lookup inode item and other
3824 * relative items in the commit root, it means the transaction of
3825 * dir/file creation has been committed, and the dir index item that we
3826 * delay to insert has also been inserted into the commit root. So
3827 * we needn't worry about the delayed insertion of the dir index item
3830 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
3831 dentry->d_name.name, dentry->d_name.len, 0);
3836 BUG_ON(ret == -ENOENT);
3837 if (check_path_shared(root, path))
3842 btrfs_free_path(path);
3843 /* Migrate the orphan reservation over */
3845 err = btrfs_block_rsv_migrate(trans->block_rsv,
3846 &root->fs_info->global_block_rsv,
3847 trans->bytes_reserved);
3850 btrfs_end_transaction(trans, root);
3851 root->fs_info->enospc_unlink = 0;
3852 return ERR_PTR(err);
3855 trans->block_rsv = &root->fs_info->global_block_rsv;
3859 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
3860 struct btrfs_root *root)
3862 if (trans->block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL) {
3863 btrfs_block_rsv_release(root, trans->block_rsv,
3864 trans->bytes_reserved);
3865 trans->block_rsv = &root->fs_info->trans_block_rsv;
3866 BUG_ON(!root->fs_info->enospc_unlink);
3867 root->fs_info->enospc_unlink = 0;
3869 btrfs_end_transaction(trans, root);
3872 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3874 struct btrfs_root *root = BTRFS_I(dir)->root;
3875 struct btrfs_trans_handle *trans;
3876 struct inode *inode = dentry->d_inode;
3879 trans = __unlink_start_trans(dir, dentry);
3881 return PTR_ERR(trans);
3883 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3885 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3886 dentry->d_name.name, dentry->d_name.len);
3890 if (inode->i_nlink == 0) {
3891 ret = btrfs_orphan_add(trans, inode);
3897 __unlink_end_trans(trans, root);
3898 btrfs_btree_balance_dirty(root);
3902 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3903 struct btrfs_root *root,
3904 struct inode *dir, u64 objectid,
3905 const char *name, int name_len)
3907 struct btrfs_path *path;
3908 struct extent_buffer *leaf;
3909 struct btrfs_dir_item *di;
3910 struct btrfs_key key;
3913 u64 dir_ino = btrfs_ino(dir);
3915 path = btrfs_alloc_path();
3919 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3920 name, name_len, -1);
3921 if (IS_ERR_OR_NULL(di)) {
3929 leaf = path->nodes[0];
3930 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3931 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3932 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3934 btrfs_abort_transaction(trans, root, ret);
3937 btrfs_release_path(path);
3939 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3940 objectid, root->root_key.objectid,
3941 dir_ino, &index, name, name_len);
3943 if (ret != -ENOENT) {
3944 btrfs_abort_transaction(trans, root, ret);
3947 di = btrfs_search_dir_index_item(root, path, dir_ino,
3949 if (IS_ERR_OR_NULL(di)) {
3954 btrfs_abort_transaction(trans, root, ret);
3958 leaf = path->nodes[0];
3959 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3960 btrfs_release_path(path);
3963 btrfs_release_path(path);
3965 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3967 btrfs_abort_transaction(trans, root, ret);
3971 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3972 inode_inc_iversion(dir);
3973 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3974 ret = btrfs_update_inode_fallback(trans, root, dir);
3976 btrfs_abort_transaction(trans, root, ret);
3978 btrfs_free_path(path);
3982 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3984 struct inode *inode = dentry->d_inode;
3986 struct btrfs_root *root = BTRFS_I(dir)->root;
3987 struct btrfs_trans_handle *trans;
3989 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
3991 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3994 trans = __unlink_start_trans(dir, dentry);
3996 return PTR_ERR(trans);
3998 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3999 err = btrfs_unlink_subvol(trans, root, dir,
4000 BTRFS_I(inode)->location.objectid,
4001 dentry->d_name.name,
4002 dentry->d_name.len);
4006 err = btrfs_orphan_add(trans, inode);
4010 /* now the directory is empty */
4011 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
4012 dentry->d_name.name, dentry->d_name.len);
4014 btrfs_i_size_write(inode, 0);
4016 __unlink_end_trans(trans, root);
4017 btrfs_btree_balance_dirty(root);
4023 * this can truncate away extent items, csum items and directory items.
4024 * It starts at a high offset and removes keys until it can't find
4025 * any higher than new_size
4027 * csum items that cross the new i_size are truncated to the new size
4030 * min_type is the minimum key type to truncate down to. If set to 0, this
4031 * will kill all the items on this inode, including the INODE_ITEM_KEY.
4033 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
4034 struct btrfs_root *root,
4035 struct inode *inode,
4036 u64 new_size, u32 min_type)
4038 struct btrfs_path *path;
4039 struct extent_buffer *leaf;
4040 struct btrfs_file_extent_item *fi;
4041 struct btrfs_key key;
4042 struct btrfs_key found_key;
4043 u64 extent_start = 0;
4044 u64 extent_num_bytes = 0;
4045 u64 extent_offset = 0;
4047 u32 found_type = (u8)-1;
4050 int pending_del_nr = 0;
4051 int pending_del_slot = 0;
4052 int extent_type = -1;
4055 u64 ino = btrfs_ino(inode);
4057 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
4059 path = btrfs_alloc_path();
4065 * We want to drop from the next block forward in case this new size is
4066 * not block aligned since we will be keeping the last block of the
4067 * extent just the way it is.
4069 if (root->ref_cows || root == root->fs_info->tree_root)
4070 btrfs_drop_extent_cache(inode, ALIGN(new_size,
4071 root->sectorsize), (u64)-1, 0);
4074 * This function is also used to drop the items in the log tree before
4075 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
4076 * it is used to drop the loged items. So we shouldn't kill the delayed
4079 if (min_type == 0 && root == BTRFS_I(inode)->root)
4080 btrfs_kill_delayed_inode_items(inode);
4083 key.offset = (u64)-1;
4087 path->leave_spinning = 1;
4088 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
4095 /* there are no items in the tree for us to truncate, we're
4098 if (path->slots[0] == 0)
4105 leaf = path->nodes[0];
4106 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4107 found_type = btrfs_key_type(&found_key);
4109 if (found_key.objectid != ino)
4112 if (found_type < min_type)
4115 item_end = found_key.offset;
4116 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4117 fi = btrfs_item_ptr(leaf, path->slots[0],
4118 struct btrfs_file_extent_item);
4119 extent_type = btrfs_file_extent_type(leaf, fi);
4120 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4122 btrfs_file_extent_num_bytes(leaf, fi);
4123 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4124 item_end += btrfs_file_extent_inline_len(leaf,
4129 if (found_type > min_type) {
4132 if (item_end < new_size)
4134 if (found_key.offset >= new_size)
4140 /* FIXME, shrink the extent if the ref count is only 1 */
4141 if (found_type != BTRFS_EXTENT_DATA_KEY)
4144 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4146 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4148 u64 orig_num_bytes =
4149 btrfs_file_extent_num_bytes(leaf, fi);
4150 extent_num_bytes = ALIGN(new_size -
4153 btrfs_set_file_extent_num_bytes(leaf, fi,
4155 num_dec = (orig_num_bytes -
4157 if (root->ref_cows && extent_start != 0)
4158 inode_sub_bytes(inode, num_dec);
4159 btrfs_mark_buffer_dirty(leaf);
4162 btrfs_file_extent_disk_num_bytes(leaf,
4164 extent_offset = found_key.offset -
4165 btrfs_file_extent_offset(leaf, fi);
4167 /* FIXME blocksize != 4096 */
4168 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4169 if (extent_start != 0) {
4172 inode_sub_bytes(inode, num_dec);
4175 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4177 * we can't truncate inline items that have had
4181 btrfs_file_extent_compression(leaf, fi) == 0 &&
4182 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4183 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
4184 u32 size = new_size - found_key.offset;
4186 if (root->ref_cows) {
4187 inode_sub_bytes(inode, item_end + 1 -
4191 btrfs_file_extent_calc_inline_size(size);
4192 btrfs_truncate_item(root, path, size, 1);
4193 } else if (root->ref_cows) {
4194 inode_sub_bytes(inode, item_end + 1 -
4200 if (!pending_del_nr) {
4201 /* no pending yet, add ourselves */
4202 pending_del_slot = path->slots[0];
4204 } else if (pending_del_nr &&
4205 path->slots[0] + 1 == pending_del_slot) {
4206 /* hop on the pending chunk */
4208 pending_del_slot = path->slots[0];
4215 if (found_extent && (root->ref_cows ||
4216 root == root->fs_info->tree_root)) {
4217 btrfs_set_path_blocking(path);
4218 ret = btrfs_free_extent(trans, root, extent_start,
4219 extent_num_bytes, 0,
4220 btrfs_header_owner(leaf),
4221 ino, extent_offset, 0);
4225 if (found_type == BTRFS_INODE_ITEM_KEY)
4228 if (path->slots[0] == 0 ||
4229 path->slots[0] != pending_del_slot) {
4230 if (pending_del_nr) {
4231 ret = btrfs_del_items(trans, root, path,
4235 btrfs_abort_transaction(trans,
4241 btrfs_release_path(path);
4248 if (pending_del_nr) {
4249 ret = btrfs_del_items(trans, root, path, pending_del_slot,
4252 btrfs_abort_transaction(trans, root, ret);
4255 btrfs_free_path(path);
4260 * btrfs_truncate_page - read, zero a chunk and write a page
4261 * @inode - inode that we're zeroing
4262 * @from - the offset to start zeroing
4263 * @len - the length to zero, 0 to zero the entire range respective to the
4265 * @front - zero up to the offset instead of from the offset on
4267 * This will find the page for the "from" offset and cow the page and zero the
4268 * part we want to zero. This is used with truncate and hole punching.
4270 int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
4273 struct address_space *mapping = inode->i_mapping;
4274 struct btrfs_root *root = BTRFS_I(inode)->root;
4275 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4276 struct btrfs_ordered_extent *ordered;
4277 struct extent_state *cached_state = NULL;
4279 u32 blocksize = root->sectorsize;
4280 pgoff_t index = from >> PAGE_CACHE_SHIFT;
4281 unsigned offset = from & (PAGE_CACHE_SIZE-1);
4283 gfp_t mask = btrfs_alloc_write_mask(mapping);
4288 if ((offset & (blocksize - 1)) == 0 &&
4289 (!len || ((len & (blocksize - 1)) == 0)))
4291 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
4296 page = find_or_create_page(mapping, index, mask);
4298 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4303 page_start = page_offset(page);
4304 page_end = page_start + PAGE_CACHE_SIZE - 1;
4306 if (!PageUptodate(page)) {
4307 ret = btrfs_readpage(NULL, page);
4309 if (page->mapping != mapping) {
4311 page_cache_release(page);
4314 if (!PageUptodate(page)) {
4319 wait_on_page_writeback(page);
4321 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
4322 set_page_extent_mapped(page);
4324 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4326 unlock_extent_cached(io_tree, page_start, page_end,
4327 &cached_state, GFP_NOFS);
4329 page_cache_release(page);
4330 btrfs_start_ordered_extent(inode, ordered, 1);
4331 btrfs_put_ordered_extent(ordered);
4335 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
4336 EXTENT_DIRTY | EXTENT_DELALLOC |
4337 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4338 0, 0, &cached_state, GFP_NOFS);
4340 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
4343 unlock_extent_cached(io_tree, page_start, page_end,
4344 &cached_state, GFP_NOFS);
4348 if (offset != PAGE_CACHE_SIZE) {
4350 len = PAGE_CACHE_SIZE - offset;
4353 memset(kaddr, 0, offset);
4355 memset(kaddr + offset, 0, len);
4356 flush_dcache_page(page);
4359 ClearPageChecked(page);
4360 set_page_dirty(page);
4361 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
4366 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
4368 page_cache_release(page);
4374 * This function puts in dummy file extents for the area we're creating a hole
4375 * for. So if we are truncating this file to a larger size we need to insert
4376 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4377 * the range between oldsize and size
4379 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4381 struct btrfs_trans_handle *trans;
4382 struct btrfs_root *root = BTRFS_I(inode)->root;
4383 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4384 struct extent_map *em = NULL;
4385 struct extent_state *cached_state = NULL;
4386 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4387 u64 hole_start = ALIGN(oldsize, root->sectorsize);
4388 u64 block_end = ALIGN(size, root->sectorsize);
4394 if (size <= hole_start)
4398 struct btrfs_ordered_extent *ordered;
4399 btrfs_wait_ordered_range(inode, hole_start,
4400 block_end - hole_start);
4401 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
4403 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
4406 unlock_extent_cached(io_tree, hole_start, block_end - 1,
4407 &cached_state, GFP_NOFS);
4408 btrfs_put_ordered_extent(ordered);
4411 cur_offset = hole_start;
4413 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
4414 block_end - cur_offset, 0);
4420 last_byte = min(extent_map_end(em), block_end);
4421 last_byte = ALIGN(last_byte , root->sectorsize);
4422 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
4423 struct extent_map *hole_em;
4424 hole_size = last_byte - cur_offset;
4426 trans = btrfs_start_transaction(root, 3);
4427 if (IS_ERR(trans)) {
4428 err = PTR_ERR(trans);
4432 err = btrfs_drop_extents(trans, root, inode,
4434 cur_offset + hole_size, 1);
4436 btrfs_abort_transaction(trans, root, err);
4437 btrfs_end_transaction(trans, root);
4441 err = btrfs_insert_file_extent(trans, root,
4442 btrfs_ino(inode), cur_offset, 0,
4443 0, hole_size, 0, hole_size,
4446 btrfs_abort_transaction(trans, root, err);
4447 btrfs_end_transaction(trans, root);
4451 btrfs_drop_extent_cache(inode, cur_offset,
4452 cur_offset + hole_size - 1, 0);
4453 hole_em = alloc_extent_map();
4455 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4456 &BTRFS_I(inode)->runtime_flags);
4459 hole_em->start = cur_offset;
4460 hole_em->len = hole_size;
4461 hole_em->orig_start = cur_offset;
4463 hole_em->block_start = EXTENT_MAP_HOLE;
4464 hole_em->block_len = 0;
4465 hole_em->orig_block_len = 0;
4466 hole_em->ram_bytes = hole_size;
4467 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
4468 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4469 hole_em->generation = trans->transid;
4472 write_lock(&em_tree->lock);
4473 err = add_extent_mapping(em_tree, hole_em, 1);
4474 write_unlock(&em_tree->lock);
4477 btrfs_drop_extent_cache(inode, cur_offset,
4481 free_extent_map(hole_em);
4483 btrfs_update_inode(trans, root, inode);
4484 btrfs_end_transaction(trans, root);
4486 free_extent_map(em);
4488 cur_offset = last_byte;
4489 if (cur_offset >= block_end)
4493 free_extent_map(em);
4494 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
4499 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
4501 struct btrfs_root *root = BTRFS_I(inode)->root;
4502 struct btrfs_trans_handle *trans;
4503 loff_t oldsize = i_size_read(inode);
4504 loff_t newsize = attr->ia_size;
4505 int mask = attr->ia_valid;
4508 if (newsize == oldsize)
4512 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4513 * special case where we need to update the times despite not having
4514 * these flags set. For all other operations the VFS set these flags
4515 * explicitly if it wants a timestamp update.
4517 if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
4518 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
4520 if (newsize > oldsize) {
4521 truncate_pagecache(inode, oldsize, newsize);
4522 ret = btrfs_cont_expand(inode, oldsize, newsize);
4526 trans = btrfs_start_transaction(root, 1);
4528 return PTR_ERR(trans);
4530 i_size_write(inode, newsize);
4531 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
4532 ret = btrfs_update_inode(trans, root, inode);
4533 btrfs_end_transaction(trans, root);
4537 * We're truncating a file that used to have good data down to
4538 * zero. Make sure it gets into the ordered flush list so that
4539 * any new writes get down to disk quickly.
4542 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4543 &BTRFS_I(inode)->runtime_flags);
4546 * 1 for the orphan item we're going to add
4547 * 1 for the orphan item deletion.
4549 trans = btrfs_start_transaction(root, 2);
4551 return PTR_ERR(trans);
4554 * We need to do this in case we fail at _any_ point during the
4555 * actual truncate. Once we do the truncate_setsize we could
4556 * invalidate pages which forces any outstanding ordered io to
4557 * be instantly completed which will give us extents that need
4558 * to be truncated. If we fail to get an orphan inode down we
4559 * could have left over extents that were never meant to live,
4560 * so we need to garuntee from this point on that everything
4561 * will be consistent.
4563 ret = btrfs_orphan_add(trans, inode);
4564 btrfs_end_transaction(trans, root);
4568 /* we don't support swapfiles, so vmtruncate shouldn't fail */
4569 truncate_setsize(inode, newsize);
4571 /* Disable nonlocked read DIO to avoid the end less truncate */
4572 btrfs_inode_block_unlocked_dio(inode);
4573 inode_dio_wait(inode);
4574 btrfs_inode_resume_unlocked_dio(inode);
4576 ret = btrfs_truncate(inode);
4577 if (ret && inode->i_nlink)
4578 btrfs_orphan_del(NULL, inode);
4584 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4586 struct inode *inode = dentry->d_inode;
4587 struct btrfs_root *root = BTRFS_I(inode)->root;
4590 if (btrfs_root_readonly(root))
4593 err = inode_change_ok(inode, attr);
4597 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
4598 err = btrfs_setsize(inode, attr);
4603 if (attr->ia_valid) {
4604 setattr_copy(inode, attr);
4605 inode_inc_iversion(inode);
4606 err = btrfs_dirty_inode(inode);
4608 if (!err && attr->ia_valid & ATTR_MODE)
4609 err = btrfs_acl_chmod(inode);
4615 void btrfs_evict_inode(struct inode *inode)
4617 struct btrfs_trans_handle *trans;
4618 struct btrfs_root *root = BTRFS_I(inode)->root;
4619 struct btrfs_block_rsv *rsv, *global_rsv;
4620 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
4623 trace_btrfs_inode_evict(inode);
4625 truncate_inode_pages(&inode->i_data, 0);
4626 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
4627 btrfs_is_free_space_inode(inode)))
4630 if (is_bad_inode(inode)) {
4631 btrfs_orphan_del(NULL, inode);
4634 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
4635 btrfs_wait_ordered_range(inode, 0, (u64)-1);
4637 if (root->fs_info->log_root_recovering) {
4638 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
4639 &BTRFS_I(inode)->runtime_flags));
4643 if (inode->i_nlink > 0) {
4644 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
4648 ret = btrfs_commit_inode_delayed_inode(inode);
4650 btrfs_orphan_del(NULL, inode);
4654 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
4656 btrfs_orphan_del(NULL, inode);
4659 rsv->size = min_size;
4661 global_rsv = &root->fs_info->global_block_rsv;
4663 btrfs_i_size_write(inode, 0);
4666 * This is a bit simpler than btrfs_truncate since we've already
4667 * reserved our space for our orphan item in the unlink, so we just
4668 * need to reserve some slack space in case we add bytes and update
4669 * inode item when doing the truncate.
4672 ret = btrfs_block_rsv_refill(root, rsv, min_size,
4673 BTRFS_RESERVE_FLUSH_LIMIT);
4676 * Try and steal from the global reserve since we will
4677 * likely not use this space anyway, we want to try as
4678 * hard as possible to get this to work.
4681 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
4684 btrfs_warn(root->fs_info,
4685 "Could not get space for a delete, will truncate on mount %d",
4687 btrfs_orphan_del(NULL, inode);
4688 btrfs_free_block_rsv(root, rsv);
4692 trans = btrfs_join_transaction(root);
4693 if (IS_ERR(trans)) {
4694 btrfs_orphan_del(NULL, inode);
4695 btrfs_free_block_rsv(root, rsv);
4699 trans->block_rsv = rsv;
4701 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
4705 trans->block_rsv = &root->fs_info->trans_block_rsv;
4706 btrfs_end_transaction(trans, root);
4708 btrfs_btree_balance_dirty(root);
4711 btrfs_free_block_rsv(root, rsv);
4714 trans->block_rsv = root->orphan_block_rsv;
4715 ret = btrfs_orphan_del(trans, inode);
4719 trans->block_rsv = &root->fs_info->trans_block_rsv;
4720 if (!(root == root->fs_info->tree_root ||
4721 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
4722 btrfs_return_ino(root, btrfs_ino(inode));
4724 btrfs_end_transaction(trans, root);
4725 btrfs_btree_balance_dirty(root);
4732 * this returns the key found in the dir entry in the location pointer.
4733 * If no dir entries were found, location->objectid is 0.
4735 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
4736 struct btrfs_key *location)
4738 const char *name = dentry->d_name.name;
4739 int namelen = dentry->d_name.len;
4740 struct btrfs_dir_item *di;
4741 struct btrfs_path *path;
4742 struct btrfs_root *root = BTRFS_I(dir)->root;
4745 path = btrfs_alloc_path();
4749 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
4754 if (IS_ERR_OR_NULL(di))
4757 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
4759 btrfs_free_path(path);
4762 location->objectid = 0;
4767 * when we hit a tree root in a directory, the btrfs part of the inode
4768 * needs to be changed to reflect the root directory of the tree root. This
4769 * is kind of like crossing a mount point.
4771 static int fixup_tree_root_location(struct btrfs_root *root,
4773 struct dentry *dentry,
4774 struct btrfs_key *location,
4775 struct btrfs_root **sub_root)
4777 struct btrfs_path *path;
4778 struct btrfs_root *new_root;
4779 struct btrfs_root_ref *ref;
4780 struct extent_buffer *leaf;
4784 path = btrfs_alloc_path();
4791 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
4792 BTRFS_I(dir)->root->root_key.objectid,
4793 location->objectid);
4800 leaf = path->nodes[0];
4801 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
4802 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
4803 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
4806 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
4807 (unsigned long)(ref + 1),
4808 dentry->d_name.len);
4812 btrfs_release_path(path);
4814 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
4815 if (IS_ERR(new_root)) {
4816 err = PTR_ERR(new_root);
4820 if (btrfs_root_refs(&new_root->root_item) == 0) {
4825 *sub_root = new_root;
4826 location->objectid = btrfs_root_dirid(&new_root->root_item);
4827 location->type = BTRFS_INODE_ITEM_KEY;
4828 location->offset = 0;
4831 btrfs_free_path(path);
4835 static void inode_tree_add(struct inode *inode)
4837 struct btrfs_root *root = BTRFS_I(inode)->root;
4838 struct btrfs_inode *entry;
4840 struct rb_node *parent;
4841 u64 ino = btrfs_ino(inode);
4843 p = &root->inode_tree.rb_node;
4846 if (inode_unhashed(inode))
4849 spin_lock(&root->inode_lock);
4852 entry = rb_entry(parent, struct btrfs_inode, rb_node);
4854 if (ino < btrfs_ino(&entry->vfs_inode))
4855 p = &parent->rb_left;
4856 else if (ino > btrfs_ino(&entry->vfs_inode))
4857 p = &parent->rb_right;
4859 WARN_ON(!(entry->vfs_inode.i_state &
4860 (I_WILL_FREE | I_FREEING)));
4861 rb_erase(parent, &root->inode_tree);
4862 RB_CLEAR_NODE(parent);
4863 spin_unlock(&root->inode_lock);
4867 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
4868 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4869 spin_unlock(&root->inode_lock);
4872 static void inode_tree_del(struct inode *inode)
4874 struct btrfs_root *root = BTRFS_I(inode)->root;
4877 spin_lock(&root->inode_lock);
4878 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
4879 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
4880 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
4881 empty = RB_EMPTY_ROOT(&root->inode_tree);
4883 spin_unlock(&root->inode_lock);
4886 * Free space cache has inodes in the tree root, but the tree root has a
4887 * root_refs of 0, so this could end up dropping the tree root as a
4888 * snapshot, so we need the extra !root->fs_info->tree_root check to
4889 * make sure we don't drop it.
4891 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
4892 root != root->fs_info->tree_root) {
4893 synchronize_srcu(&root->fs_info->subvol_srcu);
4894 spin_lock(&root->inode_lock);
4895 empty = RB_EMPTY_ROOT(&root->inode_tree);
4896 spin_unlock(&root->inode_lock);
4898 btrfs_add_dead_root(root);
4902 void btrfs_invalidate_inodes(struct btrfs_root *root)
4904 struct rb_node *node;
4905 struct rb_node *prev;
4906 struct btrfs_inode *entry;
4907 struct inode *inode;
4910 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4912 spin_lock(&root->inode_lock);
4914 node = root->inode_tree.rb_node;
4918 entry = rb_entry(node, struct btrfs_inode, rb_node);
4920 if (objectid < btrfs_ino(&entry->vfs_inode))
4921 node = node->rb_left;
4922 else if (objectid > btrfs_ino(&entry->vfs_inode))
4923 node = node->rb_right;
4929 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4930 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
4934 prev = rb_next(prev);
4938 entry = rb_entry(node, struct btrfs_inode, rb_node);
4939 objectid = btrfs_ino(&entry->vfs_inode) + 1;
4940 inode = igrab(&entry->vfs_inode);
4942 spin_unlock(&root->inode_lock);
4943 if (atomic_read(&inode->i_count) > 1)
4944 d_prune_aliases(inode);
4946 * btrfs_drop_inode will have it removed from
4947 * the inode cache when its usage count
4952 spin_lock(&root->inode_lock);
4956 if (cond_resched_lock(&root->inode_lock))
4959 node = rb_next(node);
4961 spin_unlock(&root->inode_lock);
4964 static int btrfs_init_locked_inode(struct inode *inode, void *p)
4966 struct btrfs_iget_args *args = p;
4967 inode->i_ino = args->ino;
4968 BTRFS_I(inode)->root = args->root;
4972 static int btrfs_find_actor(struct inode *inode, void *opaque)
4974 struct btrfs_iget_args *args = opaque;
4975 return args->ino == btrfs_ino(inode) &&
4976 args->root == BTRFS_I(inode)->root;
4979 static struct inode *btrfs_iget_locked(struct super_block *s,
4981 struct btrfs_root *root)
4983 struct inode *inode;
4984 struct btrfs_iget_args args;
4985 args.ino = objectid;
4988 inode = iget5_locked(s, objectid, btrfs_find_actor,
4989 btrfs_init_locked_inode,
4994 /* Get an inode object given its location and corresponding root.
4995 * Returns in *is_new if the inode was read from disk
4997 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
4998 struct btrfs_root *root, int *new)
5000 struct inode *inode;
5002 inode = btrfs_iget_locked(s, location->objectid, root);
5004 return ERR_PTR(-ENOMEM);
5006 if (inode->i_state & I_NEW) {
5007 BTRFS_I(inode)->root = root;
5008 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
5009 btrfs_read_locked_inode(inode);
5010 if (!is_bad_inode(inode)) {
5011 inode_tree_add(inode);
5012 unlock_new_inode(inode);
5016 unlock_new_inode(inode);
5018 inode = ERR_PTR(-ESTALE);
5025 static struct inode *new_simple_dir(struct super_block *s,
5026 struct btrfs_key *key,
5027 struct btrfs_root *root)
5029 struct inode *inode = new_inode(s);
5032 return ERR_PTR(-ENOMEM);
5034 BTRFS_I(inode)->root = root;
5035 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5036 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5038 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5039 inode->i_op = &btrfs_dir_ro_inode_operations;
5040 inode->i_fop = &simple_dir_operations;
5041 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5042 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5047 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5049 struct inode *inode;
5050 struct btrfs_root *root = BTRFS_I(dir)->root;
5051 struct btrfs_root *sub_root = root;
5052 struct btrfs_key location;
5056 if (dentry->d_name.len > BTRFS_NAME_LEN)
5057 return ERR_PTR(-ENAMETOOLONG);
5059 ret = btrfs_inode_by_name(dir, dentry, &location);
5061 return ERR_PTR(ret);
5063 if (location.objectid == 0)
5066 if (location.type == BTRFS_INODE_ITEM_KEY) {
5067 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
5071 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
5073 index = srcu_read_lock(&root->fs_info->subvol_srcu);
5074 ret = fixup_tree_root_location(root, dir, dentry,
5075 &location, &sub_root);
5078 inode = ERR_PTR(ret);
5080 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5082 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
5084 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
5086 if (!IS_ERR(inode) && root != sub_root) {
5087 down_read(&root->fs_info->cleanup_work_sem);
5088 if (!(inode->i_sb->s_flags & MS_RDONLY))
5089 ret = btrfs_orphan_cleanup(sub_root);
5090 up_read(&root->fs_info->cleanup_work_sem);
5092 inode = ERR_PTR(ret);
5098 static int btrfs_dentry_delete(const struct dentry *dentry)
5100 struct btrfs_root *root;
5101 struct inode *inode = dentry->d_inode;
5103 if (!inode && !IS_ROOT(dentry))
5104 inode = dentry->d_parent->d_inode;
5107 root = BTRFS_I(inode)->root;
5108 if (btrfs_root_refs(&root->root_item) == 0)
5111 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5117 static void btrfs_dentry_release(struct dentry *dentry)
5119 if (dentry->d_fsdata)
5120 kfree(dentry->d_fsdata);
5123 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5128 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
5132 unsigned char btrfs_filetype_table[] = {
5133 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5136 static int btrfs_real_readdir(struct file *filp, void *dirent,
5139 struct inode *inode = file_inode(filp);
5140 struct btrfs_root *root = BTRFS_I(inode)->root;
5141 struct btrfs_item *item;
5142 struct btrfs_dir_item *di;
5143 struct btrfs_key key;
5144 struct btrfs_key found_key;
5145 struct btrfs_path *path;
5146 struct list_head ins_list;
5147 struct list_head del_list;
5149 struct extent_buffer *leaf;
5151 unsigned char d_type;
5156 int key_type = BTRFS_DIR_INDEX_KEY;
5160 int is_curr = 0; /* filp->f_pos points to the current index? */
5162 /* FIXME, use a real flag for deciding about the key type */
5163 if (root->fs_info->tree_root == root)
5164 key_type = BTRFS_DIR_ITEM_KEY;
5166 /* special case for "." */
5167 if (filp->f_pos == 0) {
5168 over = filldir(dirent, ".", 1,
5169 filp->f_pos, btrfs_ino(inode), DT_DIR);
5174 /* special case for .., just use the back ref */
5175 if (filp->f_pos == 1) {
5176 u64 pino = parent_ino(filp->f_path.dentry);
5177 over = filldir(dirent, "..", 2,
5178 filp->f_pos, pino, DT_DIR);
5183 path = btrfs_alloc_path();
5189 if (key_type == BTRFS_DIR_INDEX_KEY) {
5190 INIT_LIST_HEAD(&ins_list);
5191 INIT_LIST_HEAD(&del_list);
5192 btrfs_get_delayed_items(inode, &ins_list, &del_list);
5195 btrfs_set_key_type(&key, key_type);
5196 key.offset = filp->f_pos;
5197 key.objectid = btrfs_ino(inode);
5199 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5204 leaf = path->nodes[0];
5205 slot = path->slots[0];
5206 if (slot >= btrfs_header_nritems(leaf)) {
5207 ret = btrfs_next_leaf(root, path);
5215 item = btrfs_item_nr(leaf, slot);
5216 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5218 if (found_key.objectid != key.objectid)
5220 if (btrfs_key_type(&found_key) != key_type)
5222 if (found_key.offset < filp->f_pos)
5224 if (key_type == BTRFS_DIR_INDEX_KEY &&
5225 btrfs_should_delete_dir_index(&del_list,
5229 filp->f_pos = found_key.offset;
5232 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5234 di_total = btrfs_item_size(leaf, item);
5236 while (di_cur < di_total) {
5237 struct btrfs_key location;
5239 if (verify_dir_item(root, leaf, di))
5242 name_len = btrfs_dir_name_len(leaf, di);
5243 if (name_len <= sizeof(tmp_name)) {
5244 name_ptr = tmp_name;
5246 name_ptr = kmalloc(name_len, GFP_NOFS);
5252 read_extent_buffer(leaf, name_ptr,
5253 (unsigned long)(di + 1), name_len);
5255 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
5256 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5259 /* is this a reference to our own snapshot? If so
5262 * In contrast to old kernels, we insert the snapshot's
5263 * dir item and dir index after it has been created, so
5264 * we won't find a reference to our own snapshot. We
5265 * still keep the following code for backward
5268 if (location.type == BTRFS_ROOT_ITEM_KEY &&
5269 location.objectid == root->root_key.objectid) {
5273 over = filldir(dirent, name_ptr, name_len,
5274 found_key.offset, location.objectid,
5278 if (name_ptr != tmp_name)
5283 di_len = btrfs_dir_name_len(leaf, di) +
5284 btrfs_dir_data_len(leaf, di) + sizeof(*di);
5286 di = (struct btrfs_dir_item *)((char *)di + di_len);
5292 if (key_type == BTRFS_DIR_INDEX_KEY) {
5295 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
5301 /* Reached end of directory/root. Bump pos past the last item. */
5302 if (key_type == BTRFS_DIR_INDEX_KEY)
5304 * 32-bit glibc will use getdents64, but then strtol -
5305 * so the last number we can serve is this.
5307 filp->f_pos = 0x7fffffff;
5313 if (key_type == BTRFS_DIR_INDEX_KEY)
5314 btrfs_put_delayed_items(&ins_list, &del_list);
5315 btrfs_free_path(path);
5319 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
5321 struct btrfs_root *root = BTRFS_I(inode)->root;
5322 struct btrfs_trans_handle *trans;
5324 bool nolock = false;
5326 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5329 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode))
5332 if (wbc->sync_mode == WB_SYNC_ALL) {
5334 trans = btrfs_join_transaction_nolock(root);
5336 trans = btrfs_join_transaction(root);
5338 return PTR_ERR(trans);
5339 ret = btrfs_commit_transaction(trans, root);
5345 * This is somewhat expensive, updating the tree every time the
5346 * inode changes. But, it is most likely to find the inode in cache.
5347 * FIXME, needs more benchmarking...there are no reasons other than performance
5348 * to keep or drop this code.
5350 static int btrfs_dirty_inode(struct inode *inode)
5352 struct btrfs_root *root = BTRFS_I(inode)->root;
5353 struct btrfs_trans_handle *trans;
5356 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5359 trans = btrfs_join_transaction(root);
5361 return PTR_ERR(trans);
5363 ret = btrfs_update_inode(trans, root, inode);
5364 if (ret && ret == -ENOSPC) {
5365 /* whoops, lets try again with the full transaction */
5366 btrfs_end_transaction(trans, root);
5367 trans = btrfs_start_transaction(root, 1);
5369 return PTR_ERR(trans);
5371 ret = btrfs_update_inode(trans, root, inode);
5373 btrfs_end_transaction(trans, root);
5374 if (BTRFS_I(inode)->delayed_node)
5375 btrfs_balance_delayed_items(root);
5381 * This is a copy of file_update_time. We need this so we can return error on
5382 * ENOSPC for updating the inode in the case of file write and mmap writes.
5384 static int btrfs_update_time(struct inode *inode, struct timespec *now,
5387 struct btrfs_root *root = BTRFS_I(inode)->root;
5389 if (btrfs_root_readonly(root))
5392 if (flags & S_VERSION)
5393 inode_inc_iversion(inode);
5394 if (flags & S_CTIME)
5395 inode->i_ctime = *now;
5396 if (flags & S_MTIME)
5397 inode->i_mtime = *now;
5398 if (flags & S_ATIME)
5399 inode->i_atime = *now;
5400 return btrfs_dirty_inode(inode);
5404 * find the highest existing sequence number in a directory
5405 * and then set the in-memory index_cnt variable to reflect
5406 * free sequence numbers
5408 static int btrfs_set_inode_index_count(struct inode *inode)
5410 struct btrfs_root *root = BTRFS_I(inode)->root;
5411 struct btrfs_key key, found_key;
5412 struct btrfs_path *path;
5413 struct extent_buffer *leaf;
5416 key.objectid = btrfs_ino(inode);
5417 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
5418 key.offset = (u64)-1;
5420 path = btrfs_alloc_path();
5424 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5427 /* FIXME: we should be able to handle this */
5433 * MAGIC NUMBER EXPLANATION:
5434 * since we search a directory based on f_pos we have to start at 2
5435 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5436 * else has to start at 2
5438 if (path->slots[0] == 0) {
5439 BTRFS_I(inode)->index_cnt = 2;
5445 leaf = path->nodes[0];
5446 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5448 if (found_key.objectid != btrfs_ino(inode) ||
5449 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
5450 BTRFS_I(inode)->index_cnt = 2;
5454 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
5456 btrfs_free_path(path);
5461 * helper to find a free sequence number in a given directory. This current
5462 * code is very simple, later versions will do smarter things in the btree
5464 int btrfs_set_inode_index(struct inode *dir, u64 *index)
5468 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
5469 ret = btrfs_inode_delayed_dir_index_count(dir);
5471 ret = btrfs_set_inode_index_count(dir);
5477 *index = BTRFS_I(dir)->index_cnt;
5478 BTRFS_I(dir)->index_cnt++;
5483 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5484 struct btrfs_root *root,
5486 const char *name, int name_len,
5487 u64 ref_objectid, u64 objectid,
5488 umode_t mode, u64 *index)
5490 struct inode *inode;
5491 struct btrfs_inode_item *inode_item;
5492 struct btrfs_key *location;
5493 struct btrfs_path *path;
5494 struct btrfs_inode_ref *ref;
5495 struct btrfs_key key[2];
5501 path = btrfs_alloc_path();
5503 return ERR_PTR(-ENOMEM);
5505 inode = new_inode(root->fs_info->sb);
5507 btrfs_free_path(path);
5508 return ERR_PTR(-ENOMEM);
5512 * we have to initialize this early, so we can reclaim the inode
5513 * number if we fail afterwards in this function.
5515 inode->i_ino = objectid;
5518 trace_btrfs_inode_request(dir);
5520 ret = btrfs_set_inode_index(dir, index);
5522 btrfs_free_path(path);
5524 return ERR_PTR(ret);
5528 * index_cnt is ignored for everything but a dir,
5529 * btrfs_get_inode_index_count has an explanation for the magic
5532 BTRFS_I(inode)->index_cnt = 2;
5533 BTRFS_I(inode)->root = root;
5534 BTRFS_I(inode)->generation = trans->transid;
5535 inode->i_generation = BTRFS_I(inode)->generation;
5538 * We could have gotten an inode number from somebody who was fsynced
5539 * and then removed in this same transaction, so let's just set full
5540 * sync since it will be a full sync anyway and this will blow away the
5541 * old info in the log.
5543 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5550 key[0].objectid = objectid;
5551 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
5555 * Start new inodes with an inode_ref. This is slightly more
5556 * efficient for small numbers of hard links since they will
5557 * be packed into one item. Extended refs will kick in if we
5558 * add more hard links than can fit in the ref item.
5560 key[1].objectid = objectid;
5561 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
5562 key[1].offset = ref_objectid;
5564 sizes[0] = sizeof(struct btrfs_inode_item);
5565 sizes[1] = name_len + sizeof(*ref);
5567 path->leave_spinning = 1;
5568 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
5572 inode_init_owner(inode, dir, mode);
5573 inode_set_bytes(inode, 0);
5574 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
5575 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
5576 struct btrfs_inode_item);
5577 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
5578 sizeof(*inode_item));
5579 fill_inode_item(trans, path->nodes[0], inode_item, inode);
5581 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
5582 struct btrfs_inode_ref);
5583 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
5584 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
5585 ptr = (unsigned long)(ref + 1);
5586 write_extent_buffer(path->nodes[0], name, ptr, name_len);
5588 btrfs_mark_buffer_dirty(path->nodes[0]);
5589 btrfs_free_path(path);
5591 location = &BTRFS_I(inode)->location;
5592 location->objectid = objectid;
5593 location->offset = 0;
5594 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
5596 btrfs_inherit_iflags(inode, dir);
5598 if (S_ISREG(mode)) {
5599 if (btrfs_test_opt(root, NODATASUM))
5600 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
5601 if (btrfs_test_opt(root, NODATACOW))
5602 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
5603 BTRFS_INODE_NODATASUM;
5606 insert_inode_hash(inode);
5607 inode_tree_add(inode);
5609 trace_btrfs_inode_new(inode);
5610 btrfs_set_inode_last_trans(trans, inode);
5612 btrfs_update_root_times(trans, root);
5617 BTRFS_I(dir)->index_cnt--;
5618 btrfs_free_path(path);
5620 return ERR_PTR(ret);
5623 static inline u8 btrfs_inode_type(struct inode *inode)
5625 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
5629 * utility function to add 'inode' into 'parent_inode' with
5630 * a give name and a given sequence number.
5631 * if 'add_backref' is true, also insert a backref from the
5632 * inode to the parent directory.
5634 int btrfs_add_link(struct btrfs_trans_handle *trans,
5635 struct inode *parent_inode, struct inode *inode,
5636 const char *name, int name_len, int add_backref, u64 index)
5639 struct btrfs_key key;
5640 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
5641 u64 ino = btrfs_ino(inode);
5642 u64 parent_ino = btrfs_ino(parent_inode);
5644 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5645 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
5648 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
5652 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5653 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
5654 key.objectid, root->root_key.objectid,
5655 parent_ino, index, name, name_len);
5656 } else if (add_backref) {
5657 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
5661 /* Nothing to clean up yet */
5665 ret = btrfs_insert_dir_item(trans, root, name, name_len,
5667 btrfs_inode_type(inode), index);
5668 if (ret == -EEXIST || ret == -EOVERFLOW)
5671 btrfs_abort_transaction(trans, root, ret);
5675 btrfs_i_size_write(parent_inode, parent_inode->i_size +
5677 inode_inc_iversion(parent_inode);
5678 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
5679 ret = btrfs_update_inode(trans, root, parent_inode);
5681 btrfs_abort_transaction(trans, root, ret);
5685 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
5688 err = btrfs_del_root_ref(trans, root->fs_info->tree_root,
5689 key.objectid, root->root_key.objectid,
5690 parent_ino, &local_index, name, name_len);
5692 } else if (add_backref) {
5696 err = btrfs_del_inode_ref(trans, root, name, name_len,
5697 ino, parent_ino, &local_index);
5702 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
5703 struct inode *dir, struct dentry *dentry,
5704 struct inode *inode, int backref, u64 index)
5706 int err = btrfs_add_link(trans, dir, inode,
5707 dentry->d_name.name, dentry->d_name.len,
5714 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
5715 umode_t mode, dev_t rdev)
5717 struct btrfs_trans_handle *trans;
5718 struct btrfs_root *root = BTRFS_I(dir)->root;
5719 struct inode *inode = NULL;
5725 if (!new_valid_dev(rdev))
5729 * 2 for inode item and ref
5731 * 1 for xattr if selinux is on
5733 trans = btrfs_start_transaction(root, 5);
5735 return PTR_ERR(trans);
5737 err = btrfs_find_free_ino(root, &objectid);
5741 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5742 dentry->d_name.len, btrfs_ino(dir), objectid,
5744 if (IS_ERR(inode)) {
5745 err = PTR_ERR(inode);
5749 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5756 * If the active LSM wants to access the inode during
5757 * d_instantiate it needs these. Smack checks to see
5758 * if the filesystem supports xattrs by looking at the
5762 inode->i_op = &btrfs_special_inode_operations;
5763 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5767 init_special_inode(inode, inode->i_mode, rdev);
5768 btrfs_update_inode(trans, root, inode);
5769 d_instantiate(dentry, inode);
5772 btrfs_end_transaction(trans, root);
5773 btrfs_btree_balance_dirty(root);
5775 inode_dec_link_count(inode);
5781 static int btrfs_create(struct inode *dir, struct dentry *dentry,
5782 umode_t mode, bool excl)
5784 struct btrfs_trans_handle *trans;
5785 struct btrfs_root *root = BTRFS_I(dir)->root;
5786 struct inode *inode = NULL;
5787 int drop_inode_on_err = 0;
5793 * 2 for inode item and ref
5795 * 1 for xattr if selinux is on
5797 trans = btrfs_start_transaction(root, 5);
5799 return PTR_ERR(trans);
5801 err = btrfs_find_free_ino(root, &objectid);
5805 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5806 dentry->d_name.len, btrfs_ino(dir), objectid,
5808 if (IS_ERR(inode)) {
5809 err = PTR_ERR(inode);
5812 drop_inode_on_err = 1;
5814 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5818 err = btrfs_update_inode(trans, root, inode);
5823 * If the active LSM wants to access the inode during
5824 * d_instantiate it needs these. Smack checks to see
5825 * if the filesystem supports xattrs by looking at the
5828 inode->i_fop = &btrfs_file_operations;
5829 inode->i_op = &btrfs_file_inode_operations;
5831 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
5835 inode->i_mapping->a_ops = &btrfs_aops;
5836 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5837 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5838 d_instantiate(dentry, inode);
5841 btrfs_end_transaction(trans, root);
5842 if (err && drop_inode_on_err) {
5843 inode_dec_link_count(inode);
5846 btrfs_btree_balance_dirty(root);
5850 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
5851 struct dentry *dentry)
5853 struct btrfs_trans_handle *trans;
5854 struct btrfs_root *root = BTRFS_I(dir)->root;
5855 struct inode *inode = old_dentry->d_inode;
5860 /* do not allow sys_link's with other subvols of the same device */
5861 if (root->objectid != BTRFS_I(inode)->root->objectid)
5864 if (inode->i_nlink >= BTRFS_LINK_MAX)
5867 err = btrfs_set_inode_index(dir, &index);
5872 * 2 items for inode and inode ref
5873 * 2 items for dir items
5874 * 1 item for parent inode
5876 trans = btrfs_start_transaction(root, 5);
5877 if (IS_ERR(trans)) {
5878 err = PTR_ERR(trans);
5882 btrfs_inc_nlink(inode);
5883 inode_inc_iversion(inode);
5884 inode->i_ctime = CURRENT_TIME;
5886 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
5888 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
5893 struct dentry *parent = dentry->d_parent;
5894 err = btrfs_update_inode(trans, root, inode);
5897 d_instantiate(dentry, inode);
5898 btrfs_log_new_name(trans, inode, NULL, parent);
5901 btrfs_end_transaction(trans, root);
5904 inode_dec_link_count(inode);
5907 btrfs_btree_balance_dirty(root);
5911 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
5913 struct inode *inode = NULL;
5914 struct btrfs_trans_handle *trans;
5915 struct btrfs_root *root = BTRFS_I(dir)->root;
5917 int drop_on_err = 0;
5922 * 2 items for inode and ref
5923 * 2 items for dir items
5924 * 1 for xattr if selinux is on
5926 trans = btrfs_start_transaction(root, 5);
5928 return PTR_ERR(trans);
5930 err = btrfs_find_free_ino(root, &objectid);
5934 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5935 dentry->d_name.len, btrfs_ino(dir), objectid,
5936 S_IFDIR | mode, &index);
5937 if (IS_ERR(inode)) {
5938 err = PTR_ERR(inode);
5944 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
5948 inode->i_op = &btrfs_dir_inode_operations;
5949 inode->i_fop = &btrfs_dir_file_operations;
5951 btrfs_i_size_write(inode, 0);
5952 err = btrfs_update_inode(trans, root, inode);
5956 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
5957 dentry->d_name.len, 0, index);
5961 d_instantiate(dentry, inode);
5965 btrfs_end_transaction(trans, root);
5968 btrfs_btree_balance_dirty(root);
5972 /* helper for btfs_get_extent. Given an existing extent in the tree,
5973 * and an extent that you want to insert, deal with overlap and insert
5974 * the new extent into the tree.
5976 static int merge_extent_mapping(struct extent_map_tree *em_tree,
5977 struct extent_map *existing,
5978 struct extent_map *em,
5979 u64 map_start, u64 map_len)
5983 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
5984 start_diff = map_start - em->start;
5985 em->start = map_start;
5987 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
5988 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
5989 em->block_start += start_diff;
5990 em->block_len -= start_diff;
5992 return add_extent_mapping(em_tree, em, 0);
5995 static noinline int uncompress_inline(struct btrfs_path *path,
5996 struct inode *inode, struct page *page,
5997 size_t pg_offset, u64 extent_offset,
5998 struct btrfs_file_extent_item *item)
6001 struct extent_buffer *leaf = path->nodes[0];
6004 unsigned long inline_size;
6008 WARN_ON(pg_offset != 0);
6009 compress_type = btrfs_file_extent_compression(leaf, item);
6010 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6011 inline_size = btrfs_file_extent_inline_item_len(leaf,
6012 btrfs_item_nr(leaf, path->slots[0]));
6013 tmp = kmalloc(inline_size, GFP_NOFS);
6016 ptr = btrfs_file_extent_inline_start(item);
6018 read_extent_buffer(leaf, tmp, ptr, inline_size);
6020 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
6021 ret = btrfs_decompress(compress_type, tmp, page,
6022 extent_offset, inline_size, max_size);
6024 char *kaddr = kmap_atomic(page);
6025 unsigned long copy_size = min_t(u64,
6026 PAGE_CACHE_SIZE - pg_offset,
6027 max_size - extent_offset);
6028 memset(kaddr + pg_offset, 0, copy_size);
6029 kunmap_atomic(kaddr);
6036 * a bit scary, this does extent mapping from logical file offset to the disk.
6037 * the ugly parts come from merging extents from the disk with the in-ram
6038 * representation. This gets more complex because of the data=ordered code,
6039 * where the in-ram extents might be locked pending data=ordered completion.
6041 * This also copies inline extents directly into the page.
6044 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
6045 size_t pg_offset, u64 start, u64 len,
6051 u64 extent_start = 0;
6053 u64 objectid = btrfs_ino(inode);
6055 struct btrfs_path *path = NULL;
6056 struct btrfs_root *root = BTRFS_I(inode)->root;
6057 struct btrfs_file_extent_item *item;
6058 struct extent_buffer *leaf;
6059 struct btrfs_key found_key;
6060 struct extent_map *em = NULL;
6061 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
6062 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6063 struct btrfs_trans_handle *trans = NULL;
6067 read_lock(&em_tree->lock);
6068 em = lookup_extent_mapping(em_tree, start, len);
6070 em->bdev = root->fs_info->fs_devices->latest_bdev;
6071 read_unlock(&em_tree->lock);
6074 if (em->start > start || em->start + em->len <= start)
6075 free_extent_map(em);
6076 else if (em->block_start == EXTENT_MAP_INLINE && page)
6077 free_extent_map(em);
6081 em = alloc_extent_map();
6086 em->bdev = root->fs_info->fs_devices->latest_bdev;
6087 em->start = EXTENT_MAP_HOLE;
6088 em->orig_start = EXTENT_MAP_HOLE;
6090 em->block_len = (u64)-1;
6093 path = btrfs_alloc_path();
6099 * Chances are we'll be called again, so go ahead and do
6105 ret = btrfs_lookup_file_extent(trans, root, path,
6106 objectid, start, trans != NULL);
6113 if (path->slots[0] == 0)
6118 leaf = path->nodes[0];
6119 item = btrfs_item_ptr(leaf, path->slots[0],
6120 struct btrfs_file_extent_item);
6121 /* are we inside the extent that was found? */
6122 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6123 found_type = btrfs_key_type(&found_key);
6124 if (found_key.objectid != objectid ||
6125 found_type != BTRFS_EXTENT_DATA_KEY) {
6129 found_type = btrfs_file_extent_type(leaf, item);
6130 extent_start = found_key.offset;
6131 compress_type = btrfs_file_extent_compression(leaf, item);
6132 if (found_type == BTRFS_FILE_EXTENT_REG ||
6133 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6134 extent_end = extent_start +
6135 btrfs_file_extent_num_bytes(leaf, item);
6136 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6138 size = btrfs_file_extent_inline_len(leaf, item);
6139 extent_end = ALIGN(extent_start + size, root->sectorsize);
6142 if (start >= extent_end) {
6144 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6145 ret = btrfs_next_leaf(root, path);
6152 leaf = path->nodes[0];
6154 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6155 if (found_key.objectid != objectid ||
6156 found_key.type != BTRFS_EXTENT_DATA_KEY)
6158 if (start + len <= found_key.offset)
6161 em->orig_start = start;
6162 em->len = found_key.offset - start;
6166 em->ram_bytes = btrfs_file_extent_ram_bytes(leaf, item);
6167 if (found_type == BTRFS_FILE_EXTENT_REG ||
6168 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6169 em->start = extent_start;
6170 em->len = extent_end - extent_start;
6171 em->orig_start = extent_start -
6172 btrfs_file_extent_offset(leaf, item);
6173 em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
6175 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
6177 em->block_start = EXTENT_MAP_HOLE;
6180 if (compress_type != BTRFS_COMPRESS_NONE) {
6181 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6182 em->compress_type = compress_type;
6183 em->block_start = bytenr;
6184 em->block_len = em->orig_block_len;
6186 bytenr += btrfs_file_extent_offset(leaf, item);
6187 em->block_start = bytenr;
6188 em->block_len = em->len;
6189 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
6190 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6193 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6197 size_t extent_offset;
6200 em->block_start = EXTENT_MAP_INLINE;
6201 if (!page || create) {
6202 em->start = extent_start;
6203 em->len = extent_end - extent_start;
6207 size = btrfs_file_extent_inline_len(leaf, item);
6208 extent_offset = page_offset(page) + pg_offset - extent_start;
6209 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
6210 size - extent_offset);
6211 em->start = extent_start + extent_offset;
6212 em->len = ALIGN(copy_size, root->sectorsize);
6213 em->orig_block_len = em->len;
6214 em->orig_start = em->start;
6215 if (compress_type) {
6216 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
6217 em->compress_type = compress_type;
6219 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6220 if (create == 0 && !PageUptodate(page)) {
6221 if (btrfs_file_extent_compression(leaf, item) !=
6222 BTRFS_COMPRESS_NONE) {
6223 ret = uncompress_inline(path, inode, page,
6225 extent_offset, item);
6226 BUG_ON(ret); /* -ENOMEM */
6229 read_extent_buffer(leaf, map + pg_offset, ptr,
6231 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
6232 memset(map + pg_offset + copy_size, 0,
6233 PAGE_CACHE_SIZE - pg_offset -
6238 flush_dcache_page(page);
6239 } else if (create && PageUptodate(page)) {
6243 free_extent_map(em);
6246 btrfs_release_path(path);
6247 trans = btrfs_join_transaction(root);
6250 return ERR_CAST(trans);
6254 write_extent_buffer(leaf, map + pg_offset, ptr,
6257 btrfs_mark_buffer_dirty(leaf);
6259 set_extent_uptodate(io_tree, em->start,
6260 extent_map_end(em) - 1, NULL, GFP_NOFS);
6263 WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
6267 em->orig_start = start;
6270 em->block_start = EXTENT_MAP_HOLE;
6271 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
6273 btrfs_release_path(path);
6274 if (em->start > start || extent_map_end(em) <= start) {
6275 btrfs_err(root->fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]",
6276 (unsigned long long)em->start,
6277 (unsigned long long)em->len,
6278 (unsigned long long)start,
6279 (unsigned long long)len);
6285 write_lock(&em_tree->lock);
6286 ret = add_extent_mapping(em_tree, em, 0);
6287 /* it is possible that someone inserted the extent into the tree
6288 * while we had the lock dropped. It is also possible that
6289 * an overlapping map exists in the tree
6291 if (ret == -EEXIST) {
6292 struct extent_map *existing;
6296 existing = lookup_extent_mapping(em_tree, start, len);
6297 if (existing && (existing->start > start ||
6298 existing->start + existing->len <= start)) {
6299 free_extent_map(existing);
6303 existing = lookup_extent_mapping(em_tree, em->start,
6306 err = merge_extent_mapping(em_tree, existing,
6309 free_extent_map(existing);
6311 free_extent_map(em);
6316 free_extent_map(em);
6320 free_extent_map(em);
6325 write_unlock(&em_tree->lock);
6329 trace_btrfs_get_extent(root, em);
6332 btrfs_free_path(path);
6334 ret = btrfs_end_transaction(trans, root);
6339 free_extent_map(em);
6340 return ERR_PTR(err);
6342 BUG_ON(!em); /* Error is always set */
6346 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
6347 size_t pg_offset, u64 start, u64 len,
6350 struct extent_map *em;
6351 struct extent_map *hole_em = NULL;
6352 u64 range_start = start;
6358 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
6365 * - a pre-alloc extent,
6366 * there might actually be delalloc bytes behind it.
6368 if (em->block_start != EXTENT_MAP_HOLE &&
6369 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6375 /* check to see if we've wrapped (len == -1 or similar) */
6384 /* ok, we didn't find anything, lets look for delalloc */
6385 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
6386 end, len, EXTENT_DELALLOC, 1);
6387 found_end = range_start + found;
6388 if (found_end < range_start)
6389 found_end = (u64)-1;
6392 * we didn't find anything useful, return
6393 * the original results from get_extent()
6395 if (range_start > end || found_end <= start) {
6401 /* adjust the range_start to make sure it doesn't
6402 * go backwards from the start they passed in
6404 range_start = max(start,range_start);
6405 found = found_end - range_start;
6408 u64 hole_start = start;
6411 em = alloc_extent_map();
6417 * when btrfs_get_extent can't find anything it
6418 * returns one huge hole
6420 * make sure what it found really fits our range, and
6421 * adjust to make sure it is based on the start from
6425 u64 calc_end = extent_map_end(hole_em);
6427 if (calc_end <= start || (hole_em->start > end)) {
6428 free_extent_map(hole_em);
6431 hole_start = max(hole_em->start, start);
6432 hole_len = calc_end - hole_start;
6436 if (hole_em && range_start > hole_start) {
6437 /* our hole starts before our delalloc, so we
6438 * have to return just the parts of the hole
6439 * that go until the delalloc starts
6441 em->len = min(hole_len,
6442 range_start - hole_start);
6443 em->start = hole_start;
6444 em->orig_start = hole_start;
6446 * don't adjust block start at all,
6447 * it is fixed at EXTENT_MAP_HOLE
6449 em->block_start = hole_em->block_start;
6450 em->block_len = hole_len;
6451 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6452 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6454 em->start = range_start;
6456 em->orig_start = range_start;
6457 em->block_start = EXTENT_MAP_DELALLOC;
6458 em->block_len = found;
6460 } else if (hole_em) {
6465 free_extent_map(hole_em);
6467 free_extent_map(em);
6468 return ERR_PTR(err);
6473 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6476 struct btrfs_root *root = BTRFS_I(inode)->root;
6477 struct btrfs_trans_handle *trans;
6478 struct extent_map *em;
6479 struct btrfs_key ins;
6483 trans = btrfs_join_transaction(root);
6485 return ERR_CAST(trans);
6487 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
6489 alloc_hint = get_extent_allocation_hint(inode, start, len);
6490 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
6491 alloc_hint, &ins, 1);
6497 em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
6498 ins.offset, ins.offset, ins.offset, 0);
6502 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
6503 ins.offset, ins.offset, 0);
6505 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
6509 btrfs_end_transaction(trans, root);
6514 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6515 * block must be cow'd
6517 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
6518 struct inode *inode, u64 offset, u64 *len,
6519 u64 *orig_start, u64 *orig_block_len,
6522 struct btrfs_path *path;
6524 struct extent_buffer *leaf;
6525 struct btrfs_root *root = BTRFS_I(inode)->root;
6526 struct btrfs_file_extent_item *fi;
6527 struct btrfs_key key;
6535 path = btrfs_alloc_path();
6539 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
6544 slot = path->slots[0];
6547 /* can't find the item, must cow */
6554 leaf = path->nodes[0];
6555 btrfs_item_key_to_cpu(leaf, &key, slot);
6556 if (key.objectid != btrfs_ino(inode) ||
6557 key.type != BTRFS_EXTENT_DATA_KEY) {
6558 /* not our file or wrong item type, must cow */
6562 if (key.offset > offset) {
6563 /* Wrong offset, must cow */
6567 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6568 found_type = btrfs_file_extent_type(leaf, fi);
6569 if (found_type != BTRFS_FILE_EXTENT_REG &&
6570 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6571 /* not a regular extent, must cow */
6574 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6575 backref_offset = btrfs_file_extent_offset(leaf, fi);
6577 *orig_start = key.offset - backref_offset;
6578 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
6579 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6581 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6582 if (extent_end < offset + *len) {
6583 /* extent doesn't include our full range, must cow */
6587 if (btrfs_extent_readonly(root, disk_bytenr))
6591 * look for other files referencing this extent, if we
6592 * find any we must cow
6594 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
6595 key.offset - backref_offset, disk_bytenr))
6599 * adjust disk_bytenr and num_bytes to cover just the bytes
6600 * in this extent we are about to write. If there
6601 * are any csums in that range we have to cow in order
6602 * to keep the csums correct
6604 disk_bytenr += backref_offset;
6605 disk_bytenr += offset - key.offset;
6606 num_bytes = min(offset + *len, extent_end) - offset;
6607 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
6610 * all of the above have passed, it is safe to overwrite this extent
6616 btrfs_free_path(path);
6620 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
6621 struct extent_state **cached_state, int writing)
6623 struct btrfs_ordered_extent *ordered;
6627 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6630 * We're concerned with the entire range that we're going to be
6631 * doing DIO to, so we need to make sure theres no ordered
6632 * extents in this range.
6634 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6635 lockend - lockstart + 1);
6638 * We need to make sure there are no buffered pages in this
6639 * range either, we could have raced between the invalidate in
6640 * generic_file_direct_write and locking the extent. The
6641 * invalidate needs to happen so that reads after a write do not
6644 if (!ordered && (!writing ||
6645 !test_range_bit(&BTRFS_I(inode)->io_tree,
6646 lockstart, lockend, EXTENT_UPTODATE, 0,
6650 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6651 cached_state, GFP_NOFS);
6654 btrfs_start_ordered_extent(inode, ordered, 1);
6655 btrfs_put_ordered_extent(ordered);
6657 /* Screw you mmap */
6658 ret = filemap_write_and_wait_range(inode->i_mapping,
6665 * If we found a page that couldn't be invalidated just
6666 * fall back to buffered.
6668 ret = invalidate_inode_pages2_range(inode->i_mapping,
6669 lockstart >> PAGE_CACHE_SHIFT,
6670 lockend >> PAGE_CACHE_SHIFT);
6681 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
6682 u64 len, u64 orig_start,
6683 u64 block_start, u64 block_len,
6684 u64 orig_block_len, u64 ram_bytes,
6687 struct extent_map_tree *em_tree;
6688 struct extent_map *em;
6689 struct btrfs_root *root = BTRFS_I(inode)->root;
6692 em_tree = &BTRFS_I(inode)->extent_tree;
6693 em = alloc_extent_map();
6695 return ERR_PTR(-ENOMEM);
6698 em->orig_start = orig_start;
6699 em->mod_start = start;
6702 em->block_len = block_len;
6703 em->block_start = block_start;
6704 em->bdev = root->fs_info->fs_devices->latest_bdev;
6705 em->orig_block_len = orig_block_len;
6706 em->ram_bytes = ram_bytes;
6707 em->generation = -1;
6708 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6709 if (type == BTRFS_ORDERED_PREALLOC)
6710 set_bit(EXTENT_FLAG_FILLING, &em->flags);
6713 btrfs_drop_extent_cache(inode, em->start,
6714 em->start + em->len - 1, 0);
6715 write_lock(&em_tree->lock);
6716 ret = add_extent_mapping(em_tree, em, 1);
6717 write_unlock(&em_tree->lock);
6718 } while (ret == -EEXIST);
6721 free_extent_map(em);
6722 return ERR_PTR(ret);
6729 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
6730 struct buffer_head *bh_result, int create)
6732 struct extent_map *em;
6733 struct btrfs_root *root = BTRFS_I(inode)->root;
6734 struct extent_state *cached_state = NULL;
6735 u64 start = iblock << inode->i_blkbits;
6736 u64 lockstart, lockend;
6737 u64 len = bh_result->b_size;
6738 struct btrfs_trans_handle *trans;
6739 int unlock_bits = EXTENT_LOCKED;
6743 unlock_bits |= EXTENT_DELALLOC | EXTENT_DIRTY;
6745 len = min_t(u64, len, root->sectorsize);
6748 lockend = start + len - 1;
6751 * If this errors out it's because we couldn't invalidate pagecache for
6752 * this range and we need to fallback to buffered.
6754 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, create))
6757 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
6764 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
6765 * io. INLINE is special, and we could probably kludge it in here, but
6766 * it's still buffered so for safety lets just fall back to the generic
6769 * For COMPRESSED we _have_ to read the entire extent in so we can
6770 * decompress it, so there will be buffering required no matter what we
6771 * do, so go ahead and fallback to buffered.
6773 * We return -ENOTBLK because thats what makes DIO go ahead and go back
6774 * to buffered IO. Don't blame me, this is the price we pay for using
6777 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
6778 em->block_start == EXTENT_MAP_INLINE) {
6779 free_extent_map(em);
6784 /* Just a good old fashioned hole, return */
6785 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
6786 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
6787 free_extent_map(em);
6792 * We don't allocate a new extent in the following cases
6794 * 1) The inode is marked as NODATACOW. In this case we'll just use the
6796 * 2) The extent is marked as PREALLOC. We're good to go here and can
6797 * just use the extent.
6801 len = min(len, em->len - (start - em->start));
6802 lockstart = start + len;
6806 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
6807 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
6808 em->block_start != EXTENT_MAP_HOLE)) {
6811 u64 block_start, orig_start, orig_block_len, ram_bytes;
6813 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6814 type = BTRFS_ORDERED_PREALLOC;
6816 type = BTRFS_ORDERED_NOCOW;
6817 len = min(len, em->len - (start - em->start));
6818 block_start = em->block_start + (start - em->start);
6821 * we're not going to log anything, but we do need
6822 * to make sure the current transaction stays open
6823 * while we look for nocow cross refs
6825 trans = btrfs_join_transaction(root);
6829 if (can_nocow_odirect(trans, inode, start, &len, &orig_start,
6830 &orig_block_len, &ram_bytes) == 1) {
6831 if (type == BTRFS_ORDERED_PREALLOC) {
6832 free_extent_map(em);
6833 em = create_pinned_em(inode, start, len,
6839 btrfs_end_transaction(trans, root);
6844 ret = btrfs_add_ordered_extent_dio(inode, start,
6845 block_start, len, len, type);
6846 btrfs_end_transaction(trans, root);
6848 free_extent_map(em);
6853 btrfs_end_transaction(trans, root);
6857 * this will cow the extent, reset the len in case we changed
6860 len = bh_result->b_size;
6861 free_extent_map(em);
6862 em = btrfs_new_extent_direct(inode, start, len);
6867 len = min(len, em->len - (start - em->start));
6869 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
6871 bh_result->b_size = len;
6872 bh_result->b_bdev = em->bdev;
6873 set_buffer_mapped(bh_result);
6875 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6876 set_buffer_new(bh_result);
6879 * Need to update the i_size under the extent lock so buffered
6880 * readers will get the updated i_size when we unlock.
6882 if (start + len > i_size_read(inode))
6883 i_size_write(inode, start + len);
6885 spin_lock(&BTRFS_I(inode)->lock);
6886 BTRFS_I(inode)->outstanding_extents++;
6887 spin_unlock(&BTRFS_I(inode)->lock);
6889 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6890 lockstart + len - 1, EXTENT_DELALLOC, NULL,
6891 &cached_state, GFP_NOFS);
6896 * In the case of write we need to clear and unlock the entire range,
6897 * in the case of read we need to unlock only the end area that we
6898 * aren't using if there is any left over space.
6900 if (lockstart < lockend) {
6901 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6902 lockend, unlock_bits, 1, 0,
6903 &cached_state, GFP_NOFS);
6905 free_extent_state(cached_state);
6908 free_extent_map(em);
6913 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6914 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
6918 struct btrfs_dio_private {
6919 struct inode *inode;
6925 /* number of bios pending for this dio */
6926 atomic_t pending_bios;
6931 struct bio *orig_bio;
6934 static void btrfs_endio_direct_read(struct bio *bio, int err)
6936 struct btrfs_dio_private *dip = bio->bi_private;
6937 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
6938 struct bio_vec *bvec = bio->bi_io_vec;
6939 struct inode *inode = dip->inode;
6940 struct btrfs_root *root = BTRFS_I(inode)->root;
6943 start = dip->logical_offset;
6945 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
6946 struct page *page = bvec->bv_page;
6949 u64 private = ~(u32)0;
6950 unsigned long flags;
6952 if (get_state_private(&BTRFS_I(inode)->io_tree,
6955 local_irq_save(flags);
6956 kaddr = kmap_atomic(page);
6957 csum = btrfs_csum_data(kaddr + bvec->bv_offset,
6958 csum, bvec->bv_len);
6959 btrfs_csum_final(csum, (char *)&csum);
6960 kunmap_atomic(kaddr);
6961 local_irq_restore(flags);
6963 flush_dcache_page(bvec->bv_page);
6964 if (csum != private) {
6966 btrfs_err(root->fs_info, "csum failed ino %llu off %llu csum %u private %u",
6967 (unsigned long long)btrfs_ino(inode),
6968 (unsigned long long)start,
6969 csum, (unsigned)private);
6974 start += bvec->bv_len;
6976 } while (bvec <= bvec_end);
6978 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
6979 dip->logical_offset + dip->bytes - 1);
6980 bio->bi_private = dip->private;
6984 /* If we had a csum failure make sure to clear the uptodate flag */
6986 clear_bit(BIO_UPTODATE, &bio->bi_flags);
6987 dio_end_io(bio, err);
6990 static void btrfs_endio_direct_write(struct bio *bio, int err)
6992 struct btrfs_dio_private *dip = bio->bi_private;
6993 struct inode *inode = dip->inode;
6994 struct btrfs_root *root = BTRFS_I(inode)->root;
6995 struct btrfs_ordered_extent *ordered = NULL;
6996 u64 ordered_offset = dip->logical_offset;
6997 u64 ordered_bytes = dip->bytes;
7003 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
7005 ordered_bytes, !err);
7009 ordered->work.func = finish_ordered_fn;
7010 ordered->work.flags = 0;
7011 btrfs_queue_worker(&root->fs_info->endio_write_workers,
7015 * our bio might span multiple ordered extents. If we haven't
7016 * completed the accounting for the whole dio, go back and try again
7018 if (ordered_offset < dip->logical_offset + dip->bytes) {
7019 ordered_bytes = dip->logical_offset + dip->bytes -
7025 bio->bi_private = dip->private;
7029 /* If we had an error make sure to clear the uptodate flag */
7031 clear_bit(BIO_UPTODATE, &bio->bi_flags);
7032 dio_end_io(bio, err);
7035 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
7036 struct bio *bio, int mirror_num,
7037 unsigned long bio_flags, u64 offset)
7040 struct btrfs_root *root = BTRFS_I(inode)->root;
7041 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
7042 BUG_ON(ret); /* -ENOMEM */
7046 static void btrfs_end_dio_bio(struct bio *bio, int err)
7048 struct btrfs_dio_private *dip = bio->bi_private;
7051 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
7052 "sector %#Lx len %u err no %d\n",
7053 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
7054 (unsigned long long)bio->bi_sector, bio->bi_size, err);
7058 * before atomic variable goto zero, we must make sure
7059 * dip->errors is perceived to be set.
7061 smp_mb__before_atomic_dec();
7064 /* if there are more bios still pending for this dio, just exit */
7065 if (!atomic_dec_and_test(&dip->pending_bios))
7069 bio_io_error(dip->orig_bio);
7071 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
7072 bio_endio(dip->orig_bio, 0);
7078 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
7079 u64 first_sector, gfp_t gfp_flags)
7081 int nr_vecs = bio_get_nr_vecs(bdev);
7082 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
7085 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
7086 int rw, u64 file_offset, int skip_sum,
7089 int write = rw & REQ_WRITE;
7090 struct btrfs_root *root = BTRFS_I(inode)->root;
7094 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
7099 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
7107 if (write && async_submit) {
7108 ret = btrfs_wq_submit_bio(root->fs_info,
7109 inode, rw, bio, 0, 0,
7111 __btrfs_submit_bio_start_direct_io,
7112 __btrfs_submit_bio_done);
7116 * If we aren't doing async submit, calculate the csum of the
7119 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
7122 } else if (!skip_sum) {
7123 ret = btrfs_lookup_bio_sums_dio(root, inode, bio, file_offset);
7129 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
7135 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
7138 struct inode *inode = dip->inode;
7139 struct btrfs_root *root = BTRFS_I(inode)->root;
7141 struct bio *orig_bio = dip->orig_bio;
7142 struct bio_vec *bvec = orig_bio->bi_io_vec;
7143 u64 start_sector = orig_bio->bi_sector;
7144 u64 file_offset = dip->logical_offset;
7149 int async_submit = 0;
7151 map_length = orig_bio->bi_size;
7152 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9,
7153 &map_length, NULL, 0);
7158 if (map_length >= orig_bio->bi_size) {
7163 /* async crcs make it difficult to collect full stripe writes. */
7164 if (btrfs_get_alloc_profile(root, 1) &
7165 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))
7170 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
7173 bio->bi_private = dip;
7174 bio->bi_end_io = btrfs_end_dio_bio;
7175 atomic_inc(&dip->pending_bios);
7177 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
7178 if (unlikely(map_length < submit_len + bvec->bv_len ||
7179 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
7180 bvec->bv_offset) < bvec->bv_len)) {
7182 * inc the count before we submit the bio so
7183 * we know the end IO handler won't happen before
7184 * we inc the count. Otherwise, the dip might get freed
7185 * before we're done setting it up
7187 atomic_inc(&dip->pending_bios);
7188 ret = __btrfs_submit_dio_bio(bio, inode, rw,
7189 file_offset, skip_sum,
7193 atomic_dec(&dip->pending_bios);
7197 start_sector += submit_len >> 9;
7198 file_offset += submit_len;
7203 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
7204 start_sector, GFP_NOFS);
7207 bio->bi_private = dip;
7208 bio->bi_end_io = btrfs_end_dio_bio;
7210 map_length = orig_bio->bi_size;
7211 ret = btrfs_map_block(root->fs_info, rw,
7213 &map_length, NULL, 0);
7219 submit_len += bvec->bv_len;
7226 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
7235 * before atomic variable goto zero, we must
7236 * make sure dip->errors is perceived to be set.
7238 smp_mb__before_atomic_dec();
7239 if (atomic_dec_and_test(&dip->pending_bios))
7240 bio_io_error(dip->orig_bio);
7242 /* bio_end_io() will handle error, so we needn't return it */
7246 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
7249 struct btrfs_root *root = BTRFS_I(inode)->root;
7250 struct btrfs_dio_private *dip;
7251 struct bio_vec *bvec = bio->bi_io_vec;
7253 int write = rw & REQ_WRITE;
7256 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
7258 dip = kmalloc(sizeof(*dip), GFP_NOFS);
7264 dip->private = bio->bi_private;
7266 dip->logical_offset = file_offset;
7270 dip->bytes += bvec->bv_len;
7272 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
7274 dip->disk_bytenr = (u64)bio->bi_sector << 9;
7275 bio->bi_private = dip;
7277 dip->orig_bio = bio;
7278 atomic_set(&dip->pending_bios, 0);
7281 bio->bi_end_io = btrfs_endio_direct_write;
7283 bio->bi_end_io = btrfs_endio_direct_read;
7285 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
7290 * If this is a write, we need to clean up the reserved space and kill
7291 * the ordered extent.
7294 struct btrfs_ordered_extent *ordered;
7295 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
7296 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
7297 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
7298 btrfs_free_reserved_extent(root, ordered->start,
7300 btrfs_put_ordered_extent(ordered);
7301 btrfs_put_ordered_extent(ordered);
7303 bio_endio(bio, ret);
7306 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
7307 const struct iovec *iov, loff_t offset,
7308 unsigned long nr_segs)
7314 unsigned blocksize_mask = root->sectorsize - 1;
7315 ssize_t retval = -EINVAL;
7316 loff_t end = offset;
7318 if (offset & blocksize_mask)
7321 /* Check the memory alignment. Blocks cannot straddle pages */
7322 for (seg = 0; seg < nr_segs; seg++) {
7323 addr = (unsigned long)iov[seg].iov_base;
7324 size = iov[seg].iov_len;
7326 if ((addr & blocksize_mask) || (size & blocksize_mask))
7329 /* If this is a write we don't need to check anymore */
7334 * Check to make sure we don't have duplicate iov_base's in this
7335 * iovec, if so return EINVAL, otherwise we'll get csum errors
7336 * when reading back.
7338 for (i = seg + 1; i < nr_segs; i++) {
7339 if (iov[seg].iov_base == iov[i].iov_base)
7348 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
7349 const struct iovec *iov, loff_t offset,
7350 unsigned long nr_segs)
7352 struct file *file = iocb->ki_filp;
7353 struct inode *inode = file->f_mapping->host;
7357 bool relock = false;
7360 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
7364 atomic_inc(&inode->i_dio_count);
7365 smp_mb__after_atomic_inc();
7368 count = iov_length(iov, nr_segs);
7370 * If the write DIO is beyond the EOF, we need update
7371 * the isize, but it is protected by i_mutex. So we can
7372 * not unlock the i_mutex at this case.
7374 if (offset + count <= inode->i_size) {
7375 mutex_unlock(&inode->i_mutex);
7378 ret = btrfs_delalloc_reserve_space(inode, count);
7381 } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7382 &BTRFS_I(inode)->runtime_flags))) {
7383 inode_dio_done(inode);
7384 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7388 ret = __blockdev_direct_IO(rw, iocb, inode,
7389 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
7390 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
7391 btrfs_submit_direct, flags);
7393 if (ret < 0 && ret != -EIOCBQUEUED)
7394 btrfs_delalloc_release_space(inode, count);
7395 else if (ret >= 0 && (size_t)ret < count)
7396 btrfs_delalloc_release_space(inode,
7397 count - (size_t)ret);
7399 btrfs_delalloc_release_metadata(inode, 0);
7403 inode_dio_done(inode);
7405 mutex_lock(&inode->i_mutex);
7410 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7412 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7413 __u64 start, __u64 len)
7417 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7421 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
7424 int btrfs_readpage(struct file *file, struct page *page)
7426 struct extent_io_tree *tree;
7427 tree = &BTRFS_I(page->mapping->host)->io_tree;
7428 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
7431 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
7433 struct extent_io_tree *tree;
7436 if (current->flags & PF_MEMALLOC) {
7437 redirty_page_for_writepage(wbc, page);
7441 tree = &BTRFS_I(page->mapping->host)->io_tree;
7442 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
7445 static int btrfs_writepages(struct address_space *mapping,
7446 struct writeback_control *wbc)
7448 struct extent_io_tree *tree;
7450 tree = &BTRFS_I(mapping->host)->io_tree;
7451 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
7455 btrfs_readpages(struct file *file, struct address_space *mapping,
7456 struct list_head *pages, unsigned nr_pages)
7458 struct extent_io_tree *tree;
7459 tree = &BTRFS_I(mapping->host)->io_tree;
7460 return extent_readpages(tree, mapping, pages, nr_pages,
7463 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7465 struct extent_io_tree *tree;
7466 struct extent_map_tree *map;
7469 tree = &BTRFS_I(page->mapping->host)->io_tree;
7470 map = &BTRFS_I(page->mapping->host)->extent_tree;
7471 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
7473 ClearPagePrivate(page);
7474 set_page_private(page, 0);
7475 page_cache_release(page);
7480 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
7482 if (PageWriteback(page) || PageDirty(page))
7484 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
7487 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
7489 struct inode *inode = page->mapping->host;
7490 struct extent_io_tree *tree;
7491 struct btrfs_ordered_extent *ordered;
7492 struct extent_state *cached_state = NULL;
7493 u64 page_start = page_offset(page);
7494 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
7497 * we have the page locked, so new writeback can't start,
7498 * and the dirty bit won't be cleared while we are here.
7500 * Wait for IO on this page so that we can safely clear
7501 * the PagePrivate2 bit and do ordered accounting
7503 wait_on_page_writeback(page);
7505 tree = &BTRFS_I(inode)->io_tree;
7507 btrfs_releasepage(page, GFP_NOFS);
7510 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7511 ordered = btrfs_lookup_ordered_extent(inode, page_offset(page));
7514 * IO on this page will never be started, so we need
7515 * to account for any ordered extents now
7517 clear_extent_bit(tree, page_start, page_end,
7518 EXTENT_DIRTY | EXTENT_DELALLOC |
7519 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
7520 EXTENT_DEFRAG, 1, 0, &cached_state, GFP_NOFS);
7522 * whoever cleared the private bit is responsible
7523 * for the finish_ordered_io
7525 if (TestClearPagePrivate2(page) &&
7526 btrfs_dec_test_ordered_pending(inode, &ordered, page_start,
7527 PAGE_CACHE_SIZE, 1)) {
7528 btrfs_finish_ordered_io(ordered);
7530 btrfs_put_ordered_extent(ordered);
7531 cached_state = NULL;
7532 lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
7534 clear_extent_bit(tree, page_start, page_end,
7535 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
7536 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
7537 &cached_state, GFP_NOFS);
7538 __btrfs_releasepage(page, GFP_NOFS);
7540 ClearPageChecked(page);
7541 if (PagePrivate(page)) {
7542 ClearPagePrivate(page);
7543 set_page_private(page, 0);
7544 page_cache_release(page);
7549 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
7550 * called from a page fault handler when a page is first dirtied. Hence we must
7551 * be careful to check for EOF conditions here. We set the page up correctly
7552 * for a written page which means we get ENOSPC checking when writing into
7553 * holes and correct delalloc and unwritten extent mapping on filesystems that
7554 * support these features.
7556 * We are not allowed to take the i_mutex here so we have to play games to
7557 * protect against truncate races as the page could now be beyond EOF. Because
7558 * vmtruncate() writes the inode size before removing pages, once we have the
7559 * page lock we can determine safely if the page is beyond EOF. If it is not
7560 * beyond EOF, then the page is guaranteed safe against truncation until we
7563 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
7565 struct page *page = vmf->page;
7566 struct inode *inode = file_inode(vma->vm_file);
7567 struct btrfs_root *root = BTRFS_I(inode)->root;
7568 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7569 struct btrfs_ordered_extent *ordered;
7570 struct extent_state *cached_state = NULL;
7572 unsigned long zero_start;
7579 sb_start_pagefault(inode->i_sb);
7580 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
7582 ret = file_update_time(vma->vm_file);
7588 else /* -ENOSPC, -EIO, etc */
7589 ret = VM_FAULT_SIGBUS;
7595 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
7598 size = i_size_read(inode);
7599 page_start = page_offset(page);
7600 page_end = page_start + PAGE_CACHE_SIZE - 1;
7602 if ((page->mapping != inode->i_mapping) ||
7603 (page_start >= size)) {
7604 /* page got truncated out from underneath us */
7607 wait_on_page_writeback(page);
7609 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state);
7610 set_page_extent_mapped(page);
7613 * we can't set the delalloc bits if there are pending ordered
7614 * extents. Drop our locks and wait for them to finish
7616 ordered = btrfs_lookup_ordered_extent(inode, page_start);
7618 unlock_extent_cached(io_tree, page_start, page_end,
7619 &cached_state, GFP_NOFS);
7621 btrfs_start_ordered_extent(inode, ordered, 1);
7622 btrfs_put_ordered_extent(ordered);
7627 * XXX - page_mkwrite gets called every time the page is dirtied, even
7628 * if it was already dirty, so for space accounting reasons we need to
7629 * clear any delalloc bits for the range we are fixing to save. There
7630 * is probably a better way to do this, but for now keep consistent with
7631 * prepare_pages in the normal write path.
7633 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
7634 EXTENT_DIRTY | EXTENT_DELALLOC |
7635 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
7636 0, 0, &cached_state, GFP_NOFS);
7638 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
7641 unlock_extent_cached(io_tree, page_start, page_end,
7642 &cached_state, GFP_NOFS);
7643 ret = VM_FAULT_SIGBUS;
7648 /* page is wholly or partially inside EOF */
7649 if (page_start + PAGE_CACHE_SIZE > size)
7650 zero_start = size & ~PAGE_CACHE_MASK;
7652 zero_start = PAGE_CACHE_SIZE;
7654 if (zero_start != PAGE_CACHE_SIZE) {
7656 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
7657 flush_dcache_page(page);
7660 ClearPageChecked(page);
7661 set_page_dirty(page);
7662 SetPageUptodate(page);
7664 BTRFS_I(inode)->last_trans = root->fs_info->generation;
7665 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
7666 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
7668 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
7672 sb_end_pagefault(inode->i_sb);
7673 return VM_FAULT_LOCKED;
7677 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
7679 sb_end_pagefault(inode->i_sb);
7683 static int btrfs_truncate(struct inode *inode)
7685 struct btrfs_root *root = BTRFS_I(inode)->root;
7686 struct btrfs_block_rsv *rsv;
7689 struct btrfs_trans_handle *trans;
7690 u64 mask = root->sectorsize - 1;
7691 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
7693 ret = btrfs_truncate_page(inode, inode->i_size, 0, 0);
7697 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
7698 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
7701 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
7702 * 3 things going on here
7704 * 1) We need to reserve space for our orphan item and the space to
7705 * delete our orphan item. Lord knows we don't want to have a dangling
7706 * orphan item because we didn't reserve space to remove it.
7708 * 2) We need to reserve space to update our inode.
7710 * 3) We need to have something to cache all the space that is going to
7711 * be free'd up by the truncate operation, but also have some slack
7712 * space reserved in case it uses space during the truncate (thank you
7713 * very much snapshotting).
7715 * And we need these to all be seperate. The fact is we can use alot of
7716 * space doing the truncate, and we have no earthly idea how much space
7717 * we will use, so we need the truncate reservation to be seperate so it
7718 * doesn't end up using space reserved for updating the inode or
7719 * removing the orphan item. We also need to be able to stop the
7720 * transaction and start a new one, which means we need to be able to
7721 * update the inode several times, and we have no idea of knowing how
7722 * many times that will be, so we can't just reserve 1 item for the
7723 * entirety of the opration, so that has to be done seperately as well.
7724 * Then there is the orphan item, which does indeed need to be held on
7725 * to for the whole operation, and we need nobody to touch this reserved
7726 * space except the orphan code.
7728 * So that leaves us with
7730 * 1) root->orphan_block_rsv - for the orphan deletion.
7731 * 2) rsv - for the truncate reservation, which we will steal from the
7732 * transaction reservation.
7733 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
7734 * updating the inode.
7736 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
7739 rsv->size = min_size;
7743 * 1 for the truncate slack space
7744 * 1 for updating the inode.
7746 trans = btrfs_start_transaction(root, 2);
7747 if (IS_ERR(trans)) {
7748 err = PTR_ERR(trans);
7752 /* Migrate the slack space for the truncate to our reserve */
7753 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
7758 * setattr is responsible for setting the ordered_data_close flag,
7759 * but that is only tested during the last file release. That
7760 * could happen well after the next commit, leaving a great big
7761 * window where new writes may get lost if someone chooses to write
7762 * to this file after truncating to zero
7764 * The inode doesn't have any dirty data here, and so if we commit
7765 * this is a noop. If someone immediately starts writing to the inode
7766 * it is very likely we'll catch some of their writes in this
7767 * transaction, and the commit will find this file on the ordered
7768 * data list with good things to send down.
7770 * This is a best effort solution, there is still a window where
7771 * using truncate to replace the contents of the file will
7772 * end up with a zero length file after a crash.
7774 if (inode->i_size == 0 && test_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
7775 &BTRFS_I(inode)->runtime_flags))
7776 btrfs_add_ordered_operation(trans, root, inode);
7779 * So if we truncate and then write and fsync we normally would just
7780 * write the extents that changed, which is a problem if we need to
7781 * first truncate that entire inode. So set this flag so we write out
7782 * all of the extents in the inode to the sync log so we're completely
7785 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
7786 trans->block_rsv = rsv;
7789 ret = btrfs_truncate_inode_items(trans, root, inode,
7791 BTRFS_EXTENT_DATA_KEY);
7792 if (ret != -ENOSPC) {
7797 trans->block_rsv = &root->fs_info->trans_block_rsv;
7798 ret = btrfs_update_inode(trans, root, inode);
7804 btrfs_end_transaction(trans, root);
7805 btrfs_btree_balance_dirty(root);
7807 trans = btrfs_start_transaction(root, 2);
7808 if (IS_ERR(trans)) {
7809 ret = err = PTR_ERR(trans);
7814 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
7816 BUG_ON(ret); /* shouldn't happen */
7817 trans->block_rsv = rsv;
7820 if (ret == 0 && inode->i_nlink > 0) {
7821 trans->block_rsv = root->orphan_block_rsv;
7822 ret = btrfs_orphan_del(trans, inode);
7828 trans->block_rsv = &root->fs_info->trans_block_rsv;
7829 ret = btrfs_update_inode(trans, root, inode);
7833 ret = btrfs_end_transaction(trans, root);
7834 btrfs_btree_balance_dirty(root);
7838 btrfs_free_block_rsv(root, rsv);
7847 * create a new subvolume directory/inode (helper for the ioctl).
7849 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
7850 struct btrfs_root *new_root, u64 new_dirid)
7852 struct inode *inode;
7856 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
7857 new_dirid, new_dirid,
7858 S_IFDIR | (~current_umask() & S_IRWXUGO),
7861 return PTR_ERR(inode);
7862 inode->i_op = &btrfs_dir_inode_operations;
7863 inode->i_fop = &btrfs_dir_file_operations;
7865 set_nlink(inode, 1);
7866 btrfs_i_size_write(inode, 0);
7868 err = btrfs_update_inode(trans, new_root, inode);
7874 struct inode *btrfs_alloc_inode(struct super_block *sb)
7876 struct btrfs_inode *ei;
7877 struct inode *inode;
7879 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
7886 ei->last_sub_trans = 0;
7887 ei->logged_trans = 0;
7888 ei->delalloc_bytes = 0;
7889 ei->disk_i_size = 0;
7892 ei->index_cnt = (u64)-1;
7893 ei->last_unlink_trans = 0;
7894 ei->last_log_commit = 0;
7896 spin_lock_init(&ei->lock);
7897 ei->outstanding_extents = 0;
7898 ei->reserved_extents = 0;
7900 ei->runtime_flags = 0;
7901 ei->force_compress = BTRFS_COMPRESS_NONE;
7903 ei->delayed_node = NULL;
7905 inode = &ei->vfs_inode;
7906 extent_map_tree_init(&ei->extent_tree);
7907 extent_io_tree_init(&ei->io_tree, &inode->i_data);
7908 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
7909 ei->io_tree.track_uptodate = 1;
7910 ei->io_failure_tree.track_uptodate = 1;
7911 atomic_set(&ei->sync_writers, 0);
7912 mutex_init(&ei->log_mutex);
7913 mutex_init(&ei->delalloc_mutex);
7914 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
7915 INIT_LIST_HEAD(&ei->delalloc_inodes);
7916 INIT_LIST_HEAD(&ei->ordered_operations);
7917 RB_CLEAR_NODE(&ei->rb_node);
7922 static void btrfs_i_callback(struct rcu_head *head)
7924 struct inode *inode = container_of(head, struct inode, i_rcu);
7925 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
7928 void btrfs_destroy_inode(struct inode *inode)
7930 struct btrfs_ordered_extent *ordered;
7931 struct btrfs_root *root = BTRFS_I(inode)->root;
7933 WARN_ON(!hlist_empty(&inode->i_dentry));
7934 WARN_ON(inode->i_data.nrpages);
7935 WARN_ON(BTRFS_I(inode)->outstanding_extents);
7936 WARN_ON(BTRFS_I(inode)->reserved_extents);
7937 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
7938 WARN_ON(BTRFS_I(inode)->csum_bytes);
7941 * This can happen where we create an inode, but somebody else also
7942 * created the same inode and we need to destroy the one we already
7949 * Make sure we're properly removed from the ordered operation
7953 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
7954 spin_lock(&root->fs_info->ordered_extent_lock);
7955 list_del_init(&BTRFS_I(inode)->ordered_operations);
7956 spin_unlock(&root->fs_info->ordered_extent_lock);
7959 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
7960 &BTRFS_I(inode)->runtime_flags)) {
7961 btrfs_info(root->fs_info, "inode %llu still on the orphan list",
7962 (unsigned long long)btrfs_ino(inode));
7963 atomic_dec(&root->orphan_inodes);
7967 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
7971 btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup",
7972 (unsigned long long)ordered->file_offset,
7973 (unsigned long long)ordered->len);
7974 btrfs_remove_ordered_extent(inode, ordered);
7975 btrfs_put_ordered_extent(ordered);
7976 btrfs_put_ordered_extent(ordered);
7979 inode_tree_del(inode);
7980 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
7982 btrfs_remove_delayed_node(inode);
7983 call_rcu(&inode->i_rcu, btrfs_i_callback);
7986 int btrfs_drop_inode(struct inode *inode)
7988 struct btrfs_root *root = BTRFS_I(inode)->root;
7990 /* the snap/subvol tree is on deleting */
7991 if (btrfs_root_refs(&root->root_item) == 0 &&
7992 root != root->fs_info->tree_root)
7995 return generic_drop_inode(inode);
7998 static void init_once(void *foo)
8000 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
8002 inode_init_once(&ei->vfs_inode);
8005 void btrfs_destroy_cachep(void)
8008 * Make sure all delayed rcu free inodes are flushed before we
8012 if (btrfs_inode_cachep)
8013 kmem_cache_destroy(btrfs_inode_cachep);
8014 if (btrfs_trans_handle_cachep)
8015 kmem_cache_destroy(btrfs_trans_handle_cachep);
8016 if (btrfs_transaction_cachep)
8017 kmem_cache_destroy(btrfs_transaction_cachep);
8018 if (btrfs_path_cachep)
8019 kmem_cache_destroy(btrfs_path_cachep);
8020 if (btrfs_free_space_cachep)
8021 kmem_cache_destroy(btrfs_free_space_cachep);
8022 if (btrfs_delalloc_work_cachep)
8023 kmem_cache_destroy(btrfs_delalloc_work_cachep);
8026 int btrfs_init_cachep(void)
8028 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
8029 sizeof(struct btrfs_inode), 0,
8030 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
8031 if (!btrfs_inode_cachep)
8034 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
8035 sizeof(struct btrfs_trans_handle), 0,
8036 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8037 if (!btrfs_trans_handle_cachep)
8040 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction",
8041 sizeof(struct btrfs_transaction), 0,
8042 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8043 if (!btrfs_transaction_cachep)
8046 btrfs_path_cachep = kmem_cache_create("btrfs_path",
8047 sizeof(struct btrfs_path), 0,
8048 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8049 if (!btrfs_path_cachep)
8052 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
8053 sizeof(struct btrfs_free_space), 0,
8054 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
8055 if (!btrfs_free_space_cachep)
8058 btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
8059 sizeof(struct btrfs_delalloc_work), 0,
8060 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
8062 if (!btrfs_delalloc_work_cachep)
8067 btrfs_destroy_cachep();
8071 static int btrfs_getattr(struct vfsmount *mnt,
8072 struct dentry *dentry, struct kstat *stat)
8075 struct inode *inode = dentry->d_inode;
8076 u32 blocksize = inode->i_sb->s_blocksize;
8078 generic_fillattr(inode, stat);
8079 stat->dev = BTRFS_I(inode)->root->anon_dev;
8080 stat->blksize = PAGE_CACHE_SIZE;
8082 spin_lock(&BTRFS_I(inode)->lock);
8083 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
8084 spin_unlock(&BTRFS_I(inode)->lock);
8085 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
8086 ALIGN(delalloc_bytes, blocksize)) >> 9;
8090 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
8091 struct inode *new_dir, struct dentry *new_dentry)
8093 struct btrfs_trans_handle *trans;
8094 struct btrfs_root *root = BTRFS_I(old_dir)->root;
8095 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
8096 struct inode *new_inode = new_dentry->d_inode;
8097 struct inode *old_inode = old_dentry->d_inode;
8098 struct timespec ctime = CURRENT_TIME;
8102 u64 old_ino = btrfs_ino(old_inode);
8104 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
8107 /* we only allow rename subvolume link between subvolumes */
8108 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
8111 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
8112 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
8115 if (S_ISDIR(old_inode->i_mode) && new_inode &&
8116 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
8120 /* check for collisions, even if the name isn't there */
8121 ret = btrfs_check_dir_item_collision(root, new_dir->i_ino,
8122 new_dentry->d_name.name,
8123 new_dentry->d_name.len);
8126 if (ret == -EEXIST) {
8128 * eexist without a new_inode */
8134 /* maybe -EOVERFLOW */
8141 * we're using rename to replace one file with another.
8142 * and the replacement file is large. Start IO on it now so
8143 * we don't add too much work to the end of the transaction
8145 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
8146 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
8147 filemap_flush(old_inode->i_mapping);
8149 /* close the racy window with snapshot create/destroy ioctl */
8150 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8151 down_read(&root->fs_info->subvol_sem);
8153 * We want to reserve the absolute worst case amount of items. So if
8154 * both inodes are subvols and we need to unlink them then that would
8155 * require 4 item modifications, but if they are both normal inodes it
8156 * would require 5 item modifications, so we'll assume their normal
8157 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
8158 * should cover the worst case number of items we'll modify.
8160 trans = btrfs_start_transaction(root, 11);
8161 if (IS_ERR(trans)) {
8162 ret = PTR_ERR(trans);
8167 btrfs_record_root_in_trans(trans, dest);
8169 ret = btrfs_set_inode_index(new_dir, &index);
8173 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8174 /* force full log commit if subvolume involved. */
8175 root->fs_info->last_trans_log_full_commit = trans->transid;
8177 ret = btrfs_insert_inode_ref(trans, dest,
8178 new_dentry->d_name.name,
8179 new_dentry->d_name.len,
8181 btrfs_ino(new_dir), index);
8185 * this is an ugly little race, but the rename is required
8186 * to make sure that if we crash, the inode is either at the
8187 * old name or the new one. pinning the log transaction lets
8188 * us make sure we don't allow a log commit to come in after
8189 * we unlink the name but before we add the new name back in.
8191 btrfs_pin_log_trans(root);
8194 * make sure the inode gets flushed if it is replacing
8197 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
8198 btrfs_add_ordered_operation(trans, root, old_inode);
8200 inode_inc_iversion(old_dir);
8201 inode_inc_iversion(new_dir);
8202 inode_inc_iversion(old_inode);
8203 old_dir->i_ctime = old_dir->i_mtime = ctime;
8204 new_dir->i_ctime = new_dir->i_mtime = ctime;
8205 old_inode->i_ctime = ctime;
8207 if (old_dentry->d_parent != new_dentry->d_parent)
8208 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
8210 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
8211 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
8212 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
8213 old_dentry->d_name.name,
8214 old_dentry->d_name.len);
8216 ret = __btrfs_unlink_inode(trans, root, old_dir,
8217 old_dentry->d_inode,
8218 old_dentry->d_name.name,
8219 old_dentry->d_name.len);
8221 ret = btrfs_update_inode(trans, root, old_inode);
8224 btrfs_abort_transaction(trans, root, ret);
8229 inode_inc_iversion(new_inode);
8230 new_inode->i_ctime = CURRENT_TIME;
8231 if (unlikely(btrfs_ino(new_inode) ==
8232 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
8233 root_objectid = BTRFS_I(new_inode)->location.objectid;
8234 ret = btrfs_unlink_subvol(trans, dest, new_dir,
8236 new_dentry->d_name.name,
8237 new_dentry->d_name.len);
8238 BUG_ON(new_inode->i_nlink == 0);
8240 ret = btrfs_unlink_inode(trans, dest, new_dir,
8241 new_dentry->d_inode,
8242 new_dentry->d_name.name,
8243 new_dentry->d_name.len);
8245 if (!ret && new_inode->i_nlink == 0) {
8246 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
8250 btrfs_abort_transaction(trans, root, ret);
8255 ret = btrfs_add_link(trans, new_dir, old_inode,
8256 new_dentry->d_name.name,
8257 new_dentry->d_name.len, 0, index);
8259 btrfs_abort_transaction(trans, root, ret);
8263 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
8264 struct dentry *parent = new_dentry->d_parent;
8265 btrfs_log_new_name(trans, old_inode, old_dir, parent);
8266 btrfs_end_log_trans(root);
8269 btrfs_end_transaction(trans, root);
8271 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
8272 up_read(&root->fs_info->subvol_sem);
8277 static void btrfs_run_delalloc_work(struct btrfs_work *work)
8279 struct btrfs_delalloc_work *delalloc_work;
8281 delalloc_work = container_of(work, struct btrfs_delalloc_work,
8283 if (delalloc_work->wait)
8284 btrfs_wait_ordered_range(delalloc_work->inode, 0, (u64)-1);
8286 filemap_flush(delalloc_work->inode->i_mapping);
8288 if (delalloc_work->delay_iput)
8289 btrfs_add_delayed_iput(delalloc_work->inode);
8291 iput(delalloc_work->inode);
8292 complete(&delalloc_work->completion);
8295 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
8296 int wait, int delay_iput)
8298 struct btrfs_delalloc_work *work;
8300 work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
8304 init_completion(&work->completion);
8305 INIT_LIST_HEAD(&work->list);
8306 work->inode = inode;
8308 work->delay_iput = delay_iput;
8309 work->work.func = btrfs_run_delalloc_work;
8314 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
8316 wait_for_completion(&work->completion);
8317 kmem_cache_free(btrfs_delalloc_work_cachep, work);
8321 * some fairly slow code that needs optimization. This walks the list
8322 * of all the inodes with pending delalloc and forces them to disk.
8324 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
8326 struct btrfs_inode *binode;
8327 struct inode *inode;
8328 struct btrfs_delalloc_work *work, *next;
8329 struct list_head works;
8330 struct list_head splice;
8333 if (root->fs_info->sb->s_flags & MS_RDONLY)
8336 INIT_LIST_HEAD(&works);
8337 INIT_LIST_HEAD(&splice);
8339 spin_lock(&root->fs_info->delalloc_lock);
8340 list_splice_init(&root->fs_info->delalloc_inodes, &splice);
8341 while (!list_empty(&splice)) {
8342 binode = list_entry(splice.next, struct btrfs_inode,
8345 list_del_init(&binode->delalloc_inodes);
8347 inode = igrab(&binode->vfs_inode);
8349 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
8350 &binode->runtime_flags);
8354 list_add_tail(&binode->delalloc_inodes,
8355 &root->fs_info->delalloc_inodes);
8356 spin_unlock(&root->fs_info->delalloc_lock);
8358 work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
8359 if (unlikely(!work)) {
8363 list_add_tail(&work->list, &works);
8364 btrfs_queue_worker(&root->fs_info->flush_workers,
8368 spin_lock(&root->fs_info->delalloc_lock);
8370 spin_unlock(&root->fs_info->delalloc_lock);
8372 list_for_each_entry_safe(work, next, &works, list) {
8373 list_del_init(&work->list);
8374 btrfs_wait_and_free_delalloc_work(work);
8377 /* the filemap_flush will queue IO into the worker threads, but
8378 * we have to make sure the IO is actually started and that
8379 * ordered extents get created before we return
8381 atomic_inc(&root->fs_info->async_submit_draining);
8382 while (atomic_read(&root->fs_info->nr_async_submits) ||
8383 atomic_read(&root->fs_info->async_delalloc_pages)) {
8384 wait_event(root->fs_info->async_submit_wait,
8385 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
8386 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
8388 atomic_dec(&root->fs_info->async_submit_draining);
8391 list_for_each_entry_safe(work, next, &works, list) {
8392 list_del_init(&work->list);
8393 btrfs_wait_and_free_delalloc_work(work);
8396 if (!list_empty_careful(&splice)) {
8397 spin_lock(&root->fs_info->delalloc_lock);
8398 list_splice_tail(&splice, &root->fs_info->delalloc_inodes);
8399 spin_unlock(&root->fs_info->delalloc_lock);
8404 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
8405 const char *symname)
8407 struct btrfs_trans_handle *trans;
8408 struct btrfs_root *root = BTRFS_I(dir)->root;
8409 struct btrfs_path *path;
8410 struct btrfs_key key;
8411 struct inode *inode = NULL;
8419 struct btrfs_file_extent_item *ei;
8420 struct extent_buffer *leaf;
8422 name_len = strlen(symname) + 1;
8423 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
8424 return -ENAMETOOLONG;
8427 * 2 items for inode item and ref
8428 * 2 items for dir items
8429 * 1 item for xattr if selinux is on
8431 trans = btrfs_start_transaction(root, 5);
8433 return PTR_ERR(trans);
8435 err = btrfs_find_free_ino(root, &objectid);
8439 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
8440 dentry->d_name.len, btrfs_ino(dir), objectid,
8441 S_IFLNK|S_IRWXUGO, &index);
8442 if (IS_ERR(inode)) {
8443 err = PTR_ERR(inode);
8447 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
8454 * If the active LSM wants to access the inode during
8455 * d_instantiate it needs these. Smack checks to see
8456 * if the filesystem supports xattrs by looking at the
8459 inode->i_fop = &btrfs_file_operations;
8460 inode->i_op = &btrfs_file_inode_operations;
8462 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
8466 inode->i_mapping->a_ops = &btrfs_aops;
8467 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8468 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
8473 path = btrfs_alloc_path();
8479 key.objectid = btrfs_ino(inode);
8481 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
8482 datasize = btrfs_file_extent_calc_inline_size(name_len);
8483 err = btrfs_insert_empty_item(trans, root, path, &key,
8487 btrfs_free_path(path);
8490 leaf = path->nodes[0];
8491 ei = btrfs_item_ptr(leaf, path->slots[0],
8492 struct btrfs_file_extent_item);
8493 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
8494 btrfs_set_file_extent_type(leaf, ei,
8495 BTRFS_FILE_EXTENT_INLINE);
8496 btrfs_set_file_extent_encryption(leaf, ei, 0);
8497 btrfs_set_file_extent_compression(leaf, ei, 0);
8498 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
8499 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
8501 ptr = btrfs_file_extent_inline_start(ei);
8502 write_extent_buffer(leaf, symname, ptr, name_len);
8503 btrfs_mark_buffer_dirty(leaf);
8504 btrfs_free_path(path);
8506 inode->i_op = &btrfs_symlink_inode_operations;
8507 inode->i_mapping->a_ops = &btrfs_symlink_aops;
8508 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
8509 inode_set_bytes(inode, name_len);
8510 btrfs_i_size_write(inode, name_len - 1);
8511 err = btrfs_update_inode(trans, root, inode);
8517 d_instantiate(dentry, inode);
8518 btrfs_end_transaction(trans, root);
8520 inode_dec_link_count(inode);
8523 btrfs_btree_balance_dirty(root);
8527 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
8528 u64 start, u64 num_bytes, u64 min_size,
8529 loff_t actual_len, u64 *alloc_hint,
8530 struct btrfs_trans_handle *trans)
8532 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
8533 struct extent_map *em;
8534 struct btrfs_root *root = BTRFS_I(inode)->root;
8535 struct btrfs_key ins;
8536 u64 cur_offset = start;
8540 bool own_trans = true;
8544 while (num_bytes > 0) {
8546 trans = btrfs_start_transaction(root, 3);
8547 if (IS_ERR(trans)) {
8548 ret = PTR_ERR(trans);
8553 cur_bytes = min(num_bytes, 256ULL * 1024 * 1024);
8554 cur_bytes = max(cur_bytes, min_size);
8555 ret = btrfs_reserve_extent(trans, root, cur_bytes,
8556 min_size, 0, *alloc_hint, &ins, 1);
8559 btrfs_end_transaction(trans, root);
8563 ret = insert_reserved_file_extent(trans, inode,
8564 cur_offset, ins.objectid,
8565 ins.offset, ins.offset,
8566 ins.offset, 0, 0, 0,
8567 BTRFS_FILE_EXTENT_PREALLOC);
8569 btrfs_abort_transaction(trans, root, ret);
8571 btrfs_end_transaction(trans, root);
8574 btrfs_drop_extent_cache(inode, cur_offset,
8575 cur_offset + ins.offset -1, 0);
8577 em = alloc_extent_map();
8579 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
8580 &BTRFS_I(inode)->runtime_flags);
8584 em->start = cur_offset;
8585 em->orig_start = cur_offset;
8586 em->len = ins.offset;
8587 em->block_start = ins.objectid;
8588 em->block_len = ins.offset;
8589 em->orig_block_len = ins.offset;
8590 em->ram_bytes = ins.offset;
8591 em->bdev = root->fs_info->fs_devices->latest_bdev;
8592 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
8593 em->generation = trans->transid;
8596 write_lock(&em_tree->lock);
8597 ret = add_extent_mapping(em_tree, em, 1);
8598 write_unlock(&em_tree->lock);
8601 btrfs_drop_extent_cache(inode, cur_offset,
8602 cur_offset + ins.offset - 1,
8605 free_extent_map(em);
8607 num_bytes -= ins.offset;
8608 cur_offset += ins.offset;
8609 *alloc_hint = ins.objectid + ins.offset;
8611 inode_inc_iversion(inode);
8612 inode->i_ctime = CURRENT_TIME;
8613 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
8614 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
8615 (actual_len > inode->i_size) &&
8616 (cur_offset > inode->i_size)) {
8617 if (cur_offset > actual_len)
8618 i_size = actual_len;
8620 i_size = cur_offset;
8621 i_size_write(inode, i_size);
8622 btrfs_ordered_update_i_size(inode, i_size, NULL);
8625 ret = btrfs_update_inode(trans, root, inode);
8628 btrfs_abort_transaction(trans, root, ret);
8630 btrfs_end_transaction(trans, root);
8635 btrfs_end_transaction(trans, root);
8640 int btrfs_prealloc_file_range(struct inode *inode, int mode,
8641 u64 start, u64 num_bytes, u64 min_size,
8642 loff_t actual_len, u64 *alloc_hint)
8644 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8645 min_size, actual_len, alloc_hint,
8649 int btrfs_prealloc_file_range_trans(struct inode *inode,
8650 struct btrfs_trans_handle *trans, int mode,
8651 u64 start, u64 num_bytes, u64 min_size,
8652 loff_t actual_len, u64 *alloc_hint)
8654 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
8655 min_size, actual_len, alloc_hint, trans);
8658 static int btrfs_set_page_dirty(struct page *page)
8660 return __set_page_dirty_nobuffers(page);
8663 static int btrfs_permission(struct inode *inode, int mask)
8665 struct btrfs_root *root = BTRFS_I(inode)->root;
8666 umode_t mode = inode->i_mode;
8668 if (mask & MAY_WRITE &&
8669 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
8670 if (btrfs_root_readonly(root))
8672 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
8675 return generic_permission(inode, mask);
8678 static const struct inode_operations btrfs_dir_inode_operations = {
8679 .getattr = btrfs_getattr,
8680 .lookup = btrfs_lookup,
8681 .create = btrfs_create,
8682 .unlink = btrfs_unlink,
8684 .mkdir = btrfs_mkdir,
8685 .rmdir = btrfs_rmdir,
8686 .rename = btrfs_rename,
8687 .symlink = btrfs_symlink,
8688 .setattr = btrfs_setattr,
8689 .mknod = btrfs_mknod,
8690 .setxattr = btrfs_setxattr,
8691 .getxattr = btrfs_getxattr,
8692 .listxattr = btrfs_listxattr,
8693 .removexattr = btrfs_removexattr,
8694 .permission = btrfs_permission,
8695 .get_acl = btrfs_get_acl,
8697 static const struct inode_operations btrfs_dir_ro_inode_operations = {
8698 .lookup = btrfs_lookup,
8699 .permission = btrfs_permission,
8700 .get_acl = btrfs_get_acl,
8703 static const struct file_operations btrfs_dir_file_operations = {
8704 .llseek = generic_file_llseek,
8705 .read = generic_read_dir,
8706 .readdir = btrfs_real_readdir,
8707 .unlocked_ioctl = btrfs_ioctl,
8708 #ifdef CONFIG_COMPAT
8709 .compat_ioctl = btrfs_ioctl,
8711 .release = btrfs_release_file,
8712 .fsync = btrfs_sync_file,
8715 static struct extent_io_ops btrfs_extent_io_ops = {
8716 .fill_delalloc = run_delalloc_range,
8717 .submit_bio_hook = btrfs_submit_bio_hook,
8718 .merge_bio_hook = btrfs_merge_bio_hook,
8719 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
8720 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
8721 .writepage_start_hook = btrfs_writepage_start_hook,
8722 .set_bit_hook = btrfs_set_bit_hook,
8723 .clear_bit_hook = btrfs_clear_bit_hook,
8724 .merge_extent_hook = btrfs_merge_extent_hook,
8725 .split_extent_hook = btrfs_split_extent_hook,
8729 * btrfs doesn't support the bmap operation because swapfiles
8730 * use bmap to make a mapping of extents in the file. They assume
8731 * these extents won't change over the life of the file and they
8732 * use the bmap result to do IO directly to the drive.
8734 * the btrfs bmap call would return logical addresses that aren't
8735 * suitable for IO and they also will change frequently as COW
8736 * operations happen. So, swapfile + btrfs == corruption.
8738 * For now we're avoiding this by dropping bmap.
8740 static const struct address_space_operations btrfs_aops = {
8741 .readpage = btrfs_readpage,
8742 .writepage = btrfs_writepage,
8743 .writepages = btrfs_writepages,
8744 .readpages = btrfs_readpages,
8745 .direct_IO = btrfs_direct_IO,
8746 .invalidatepage = btrfs_invalidatepage,
8747 .releasepage = btrfs_releasepage,
8748 .set_page_dirty = btrfs_set_page_dirty,
8749 .error_remove_page = generic_error_remove_page,
8752 static const struct address_space_operations btrfs_symlink_aops = {
8753 .readpage = btrfs_readpage,
8754 .writepage = btrfs_writepage,
8755 .invalidatepage = btrfs_invalidatepage,
8756 .releasepage = btrfs_releasepage,
8759 static const struct inode_operations btrfs_file_inode_operations = {
8760 .getattr = btrfs_getattr,
8761 .setattr = btrfs_setattr,
8762 .setxattr = btrfs_setxattr,
8763 .getxattr = btrfs_getxattr,
8764 .listxattr = btrfs_listxattr,
8765 .removexattr = btrfs_removexattr,
8766 .permission = btrfs_permission,
8767 .fiemap = btrfs_fiemap,
8768 .get_acl = btrfs_get_acl,
8769 .update_time = btrfs_update_time,
8771 static const struct inode_operations btrfs_special_inode_operations = {
8772 .getattr = btrfs_getattr,
8773 .setattr = btrfs_setattr,
8774 .permission = btrfs_permission,
8775 .setxattr = btrfs_setxattr,
8776 .getxattr = btrfs_getxattr,
8777 .listxattr = btrfs_listxattr,
8778 .removexattr = btrfs_removexattr,
8779 .get_acl = btrfs_get_acl,
8780 .update_time = btrfs_update_time,
8782 static const struct inode_operations btrfs_symlink_inode_operations = {
8783 .readlink = generic_readlink,
8784 .follow_link = page_follow_link_light,
8785 .put_link = page_put_link,
8786 .getattr = btrfs_getattr,
8787 .setattr = btrfs_setattr,
8788 .permission = btrfs_permission,
8789 .setxattr = btrfs_setxattr,
8790 .getxattr = btrfs_getxattr,
8791 .listxattr = btrfs_listxattr,
8792 .removexattr = btrfs_removexattr,
8793 .get_acl = btrfs_get_acl,
8794 .update_time = btrfs_update_time,
8797 const struct dentry_operations btrfs_dentry_operations = {
8798 .d_delete = btrfs_dentry_delete,
8799 .d_release = btrfs_dentry_release,