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/smp_lock.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mpage.h>
32 #include <linux/swap.h>
33 #include <linux/writeback.h>
34 #include <linux/statfs.h>
35 #include <linux/compat.h>
36 #include <linux/bit_spinlock.h>
37 #include <linux/xattr.h>
38 #include <linux/posix_acl.h>
39 #include <linux/falloc.h>
43 #include "transaction.h"
44 #include "btrfs_inode.h"
46 #include "print-tree.h"
48 #include "ordered-data.h"
51 #include "compression.h"
54 struct btrfs_iget_args {
56 struct btrfs_root *root;
59 static struct inode_operations btrfs_dir_inode_operations;
60 static struct inode_operations btrfs_symlink_inode_operations;
61 static struct inode_operations btrfs_dir_ro_inode_operations;
62 static struct inode_operations btrfs_special_inode_operations;
63 static struct inode_operations btrfs_file_inode_operations;
64 static struct address_space_operations btrfs_aops;
65 static struct address_space_operations btrfs_symlink_aops;
66 static struct file_operations btrfs_dir_file_operations;
67 static struct extent_io_ops btrfs_extent_io_ops;
69 static struct kmem_cache *btrfs_inode_cachep;
70 struct kmem_cache *btrfs_trans_handle_cachep;
71 struct kmem_cache *btrfs_transaction_cachep;
72 struct kmem_cache *btrfs_path_cachep;
75 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
76 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
77 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
78 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
79 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
80 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
81 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
82 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
85 static void btrfs_truncate(struct inode *inode);
86 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
87 static noinline int cow_file_range(struct inode *inode,
88 struct page *locked_page,
89 u64 start, u64 end, int *page_started,
90 unsigned long *nr_written, int unlock);
92 static int btrfs_init_inode_security(struct inode *inode, struct inode *dir)
96 err = btrfs_init_acl(inode, dir);
98 err = btrfs_xattr_security_init(inode, dir);
103 * this does all the hard work for inserting an inline extent into
104 * the btree. The caller should have done a btrfs_drop_extents so that
105 * no overlapping inline items exist in the btree
107 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
108 struct btrfs_root *root, struct inode *inode,
109 u64 start, size_t size, size_t compressed_size,
110 struct page **compressed_pages)
112 struct btrfs_key key;
113 struct btrfs_path *path;
114 struct extent_buffer *leaf;
115 struct page *page = NULL;
118 struct btrfs_file_extent_item *ei;
121 size_t cur_size = size;
123 unsigned long offset;
124 int use_compress = 0;
126 if (compressed_size && compressed_pages) {
128 cur_size = compressed_size;
131 path = btrfs_alloc_path();
135 path->leave_spinning = 1;
136 btrfs_set_trans_block_group(trans, inode);
138 key.objectid = inode->i_ino;
140 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
141 datasize = btrfs_file_extent_calc_inline_size(cur_size);
143 inode_add_bytes(inode, size);
144 ret = btrfs_insert_empty_item(trans, root, path, &key,
151 leaf = path->nodes[0];
152 ei = btrfs_item_ptr(leaf, path->slots[0],
153 struct btrfs_file_extent_item);
154 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
155 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
156 btrfs_set_file_extent_encryption(leaf, ei, 0);
157 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
158 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
159 ptr = btrfs_file_extent_inline_start(ei);
164 while (compressed_size > 0) {
165 cpage = compressed_pages[i];
166 cur_size = min_t(unsigned long, compressed_size,
169 kaddr = kmap_atomic(cpage, KM_USER0);
170 write_extent_buffer(leaf, kaddr, ptr, cur_size);
171 kunmap_atomic(kaddr, KM_USER0);
175 compressed_size -= cur_size;
177 btrfs_set_file_extent_compression(leaf, ei,
178 BTRFS_COMPRESS_ZLIB);
180 page = find_get_page(inode->i_mapping,
181 start >> PAGE_CACHE_SHIFT);
182 btrfs_set_file_extent_compression(leaf, ei, 0);
183 kaddr = kmap_atomic(page, KM_USER0);
184 offset = start & (PAGE_CACHE_SIZE - 1);
185 write_extent_buffer(leaf, kaddr + offset, ptr, size);
186 kunmap_atomic(kaddr, KM_USER0);
187 page_cache_release(page);
189 btrfs_mark_buffer_dirty(leaf);
190 btrfs_free_path(path);
192 BTRFS_I(inode)->disk_i_size = inode->i_size;
193 btrfs_update_inode(trans, root, inode);
196 btrfs_free_path(path);
202 * conditionally insert an inline extent into the file. This
203 * does the checks required to make sure the data is small enough
204 * to fit as an inline extent.
206 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
207 struct btrfs_root *root,
208 struct inode *inode, u64 start, u64 end,
209 size_t compressed_size,
210 struct page **compressed_pages)
212 u64 isize = i_size_read(inode);
213 u64 actual_end = min(end + 1, isize);
214 u64 inline_len = actual_end - start;
215 u64 aligned_end = (end + root->sectorsize - 1) &
216 ~((u64)root->sectorsize - 1);
218 u64 data_len = inline_len;
222 data_len = compressed_size;
225 actual_end >= PAGE_CACHE_SIZE ||
226 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
228 (actual_end & (root->sectorsize - 1)) == 0) ||
230 data_len > root->fs_info->max_inline) {
234 ret = btrfs_drop_extents(trans, root, inode, start,
235 aligned_end, aligned_end, start, &hint_byte);
238 if (isize > actual_end)
239 inline_len = min_t(u64, isize, actual_end);
240 ret = insert_inline_extent(trans, root, inode, start,
241 inline_len, compressed_size,
244 btrfs_drop_extent_cache(inode, start, aligned_end, 0);
248 struct async_extent {
253 unsigned long nr_pages;
254 struct list_head list;
259 struct btrfs_root *root;
260 struct page *locked_page;
263 struct list_head extents;
264 struct btrfs_work work;
267 static noinline int add_async_extent(struct async_cow *cow,
268 u64 start, u64 ram_size,
271 unsigned long nr_pages)
273 struct async_extent *async_extent;
275 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
276 async_extent->start = start;
277 async_extent->ram_size = ram_size;
278 async_extent->compressed_size = compressed_size;
279 async_extent->pages = pages;
280 async_extent->nr_pages = nr_pages;
281 list_add_tail(&async_extent->list, &cow->extents);
286 * we create compressed extents in two phases. The first
287 * phase compresses a range of pages that have already been
288 * locked (both pages and state bits are locked).
290 * This is done inside an ordered work queue, and the compression
291 * is spread across many cpus. The actual IO submission is step
292 * two, and the ordered work queue takes care of making sure that
293 * happens in the same order things were put onto the queue by
294 * writepages and friends.
296 * If this code finds it can't get good compression, it puts an
297 * entry onto the work queue to write the uncompressed bytes. This
298 * makes sure that both compressed inodes and uncompressed inodes
299 * are written in the same order that pdflush sent them down.
301 static noinline int compress_file_range(struct inode *inode,
302 struct page *locked_page,
304 struct async_cow *async_cow,
307 struct btrfs_root *root = BTRFS_I(inode)->root;
308 struct btrfs_trans_handle *trans;
312 u64 blocksize = root->sectorsize;
314 u64 isize = i_size_read(inode);
316 struct page **pages = NULL;
317 unsigned long nr_pages;
318 unsigned long nr_pages_ret = 0;
319 unsigned long total_compressed = 0;
320 unsigned long total_in = 0;
321 unsigned long max_compressed = 128 * 1024;
322 unsigned long max_uncompressed = 128 * 1024;
328 actual_end = min_t(u64, isize, end + 1);
331 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
332 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
335 * we don't want to send crud past the end of i_size through
336 * compression, that's just a waste of CPU time. So, if the
337 * end of the file is before the start of our current
338 * requested range of bytes, we bail out to the uncompressed
339 * cleanup code that can deal with all of this.
341 * It isn't really the fastest way to fix things, but this is a
342 * very uncommon corner.
344 if (actual_end <= start)
345 goto cleanup_and_bail_uncompressed;
347 total_compressed = actual_end - start;
349 /* we want to make sure that amount of ram required to uncompress
350 * an extent is reasonable, so we limit the total size in ram
351 * of a compressed extent to 128k. This is a crucial number
352 * because it also controls how easily we can spread reads across
353 * cpus for decompression.
355 * We also want to make sure the amount of IO required to do
356 * a random read is reasonably small, so we limit the size of
357 * a compressed extent to 128k.
359 total_compressed = min(total_compressed, max_uncompressed);
360 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
361 num_bytes = max(blocksize, num_bytes);
362 disk_num_bytes = num_bytes;
367 * we do compression for mount -o compress and when the
368 * inode has not been flagged as nocompress. This flag can
369 * change at any time if we discover bad compression ratios.
371 if (!btrfs_test_flag(inode, NOCOMPRESS) &&
372 btrfs_test_opt(root, COMPRESS)) {
374 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
376 ret = btrfs_zlib_compress_pages(inode->i_mapping, start,
377 total_compressed, pages,
378 nr_pages, &nr_pages_ret,
384 unsigned long offset = total_compressed &
385 (PAGE_CACHE_SIZE - 1);
386 struct page *page = pages[nr_pages_ret - 1];
389 /* zero the tail end of the last page, we might be
390 * sending it down to disk
393 kaddr = kmap_atomic(page, KM_USER0);
394 memset(kaddr + offset, 0,
395 PAGE_CACHE_SIZE - offset);
396 kunmap_atomic(kaddr, KM_USER0);
402 trans = btrfs_join_transaction(root, 1);
404 btrfs_set_trans_block_group(trans, inode);
406 /* lets try to make an inline extent */
407 if (ret || total_in < (actual_end - start)) {
408 /* we didn't compress the entire range, try
409 * to make an uncompressed inline extent.
411 ret = cow_file_range_inline(trans, root, inode,
412 start, end, 0, NULL);
414 /* try making a compressed inline extent */
415 ret = cow_file_range_inline(trans, root, inode,
417 total_compressed, pages);
419 btrfs_end_transaction(trans, root);
422 * inline extent creation worked, we don't need
423 * to create any more async work items. Unlock
424 * and free up our temp pages.
426 extent_clear_unlock_delalloc(inode,
427 &BTRFS_I(inode)->io_tree,
428 start, end, NULL, 1, 0,
437 * we aren't doing an inline extent round the compressed size
438 * up to a block size boundary so the allocator does sane
441 total_compressed = (total_compressed + blocksize - 1) &
445 * one last check to make sure the compression is really a
446 * win, compare the page count read with the blocks on disk
448 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
449 ~(PAGE_CACHE_SIZE - 1);
450 if (total_compressed >= total_in) {
453 disk_num_bytes = total_compressed;
454 num_bytes = total_in;
457 if (!will_compress && pages) {
459 * the compression code ran but failed to make things smaller,
460 * free any pages it allocated and our page pointer array
462 for (i = 0; i < nr_pages_ret; i++) {
463 WARN_ON(pages[i]->mapping);
464 page_cache_release(pages[i]);
468 total_compressed = 0;
471 /* flag the file so we don't compress in the future */
472 btrfs_set_flag(inode, NOCOMPRESS);
477 /* the async work queues will take care of doing actual
478 * allocation on disk for these compressed pages,
479 * and will submit them to the elevator.
481 add_async_extent(async_cow, start, num_bytes,
482 total_compressed, pages, nr_pages_ret);
484 if (start + num_bytes < end && start + num_bytes < actual_end) {
491 cleanup_and_bail_uncompressed:
493 * No compression, but we still need to write the pages in
494 * the file we've been given so far. redirty the locked
495 * page if it corresponds to our extent and set things up
496 * for the async work queue to run cow_file_range to do
497 * the normal delalloc dance
499 if (page_offset(locked_page) >= start &&
500 page_offset(locked_page) <= end) {
501 __set_page_dirty_nobuffers(locked_page);
502 /* unlocked later on in the async handlers */
504 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0);
512 for (i = 0; i < nr_pages_ret; i++) {
513 WARN_ON(pages[i]->mapping);
514 page_cache_release(pages[i]);
522 * phase two of compressed writeback. This is the ordered portion
523 * of the code, which only gets called in the order the work was
524 * queued. We walk all the async extents created by compress_file_range
525 * and send them down to the disk.
527 static noinline int submit_compressed_extents(struct inode *inode,
528 struct async_cow *async_cow)
530 struct async_extent *async_extent;
532 struct btrfs_trans_handle *trans;
533 struct btrfs_key ins;
534 struct extent_map *em;
535 struct btrfs_root *root = BTRFS_I(inode)->root;
536 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
537 struct extent_io_tree *io_tree;
540 if (list_empty(&async_cow->extents))
543 trans = btrfs_join_transaction(root, 1);
545 while (!list_empty(&async_cow->extents)) {
546 async_extent = list_entry(async_cow->extents.next,
547 struct async_extent, list);
548 list_del(&async_extent->list);
550 io_tree = &BTRFS_I(inode)->io_tree;
552 /* did the compression code fall back to uncompressed IO? */
553 if (!async_extent->pages) {
554 int page_started = 0;
555 unsigned long nr_written = 0;
557 lock_extent(io_tree, async_extent->start,
558 async_extent->start +
559 async_extent->ram_size - 1, GFP_NOFS);
561 /* allocate blocks */
562 cow_file_range(inode, async_cow->locked_page,
564 async_extent->start +
565 async_extent->ram_size - 1,
566 &page_started, &nr_written, 0);
569 * if page_started, cow_file_range inserted an
570 * inline extent and took care of all the unlocking
571 * and IO for us. Otherwise, we need to submit
572 * all those pages down to the drive.
575 extent_write_locked_range(io_tree,
576 inode, async_extent->start,
577 async_extent->start +
578 async_extent->ram_size - 1,
586 lock_extent(io_tree, async_extent->start,
587 async_extent->start + async_extent->ram_size - 1,
590 * here we're doing allocation and writeback of the
593 btrfs_drop_extent_cache(inode, async_extent->start,
594 async_extent->start +
595 async_extent->ram_size - 1, 0);
597 ret = btrfs_reserve_extent(trans, root,
598 async_extent->compressed_size,
599 async_extent->compressed_size,
603 em = alloc_extent_map(GFP_NOFS);
604 em->start = async_extent->start;
605 em->len = async_extent->ram_size;
606 em->orig_start = em->start;
608 em->block_start = ins.objectid;
609 em->block_len = ins.offset;
610 em->bdev = root->fs_info->fs_devices->latest_bdev;
611 set_bit(EXTENT_FLAG_PINNED, &em->flags);
612 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
615 spin_lock(&em_tree->lock);
616 ret = add_extent_mapping(em_tree, em);
617 spin_unlock(&em_tree->lock);
618 if (ret != -EEXIST) {
622 btrfs_drop_extent_cache(inode, async_extent->start,
623 async_extent->start +
624 async_extent->ram_size - 1, 0);
627 ret = btrfs_add_ordered_extent(inode, async_extent->start,
629 async_extent->ram_size,
631 BTRFS_ORDERED_COMPRESSED);
634 btrfs_end_transaction(trans, root);
637 * clear dirty, set writeback and unlock the pages.
639 extent_clear_unlock_delalloc(inode,
640 &BTRFS_I(inode)->io_tree,
642 async_extent->start +
643 async_extent->ram_size - 1,
644 NULL, 1, 1, 0, 1, 1, 0);
646 ret = btrfs_submit_compressed_write(inode,
648 async_extent->ram_size,
650 ins.offset, async_extent->pages,
651 async_extent->nr_pages);
654 trans = btrfs_join_transaction(root, 1);
655 alloc_hint = ins.objectid + ins.offset;
660 btrfs_end_transaction(trans, root);
665 * when extent_io.c finds a delayed allocation range in the file,
666 * the call backs end up in this code. The basic idea is to
667 * allocate extents on disk for the range, and create ordered data structs
668 * in ram to track those extents.
670 * locked_page is the page that writepage had locked already. We use
671 * it to make sure we don't do extra locks or unlocks.
673 * *page_started is set to one if we unlock locked_page and do everything
674 * required to start IO on it. It may be clean and already done with
677 static noinline int cow_file_range(struct inode *inode,
678 struct page *locked_page,
679 u64 start, u64 end, int *page_started,
680 unsigned long *nr_written,
683 struct btrfs_root *root = BTRFS_I(inode)->root;
684 struct btrfs_trans_handle *trans;
687 unsigned long ram_size;
690 u64 blocksize = root->sectorsize;
692 u64 isize = i_size_read(inode);
693 struct btrfs_key ins;
694 struct extent_map *em;
695 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
698 trans = btrfs_join_transaction(root, 1);
700 btrfs_set_trans_block_group(trans, inode);
702 actual_end = min_t(u64, isize, end + 1);
704 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
705 num_bytes = max(blocksize, num_bytes);
706 disk_num_bytes = num_bytes;
710 /* lets try to make an inline extent */
711 ret = cow_file_range_inline(trans, root, inode,
712 start, end, 0, NULL);
714 extent_clear_unlock_delalloc(inode,
715 &BTRFS_I(inode)->io_tree,
716 start, end, NULL, 1, 1,
718 *nr_written = *nr_written +
719 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
726 BUG_ON(disk_num_bytes >
727 btrfs_super_total_bytes(&root->fs_info->super_copy));
729 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
731 while (disk_num_bytes > 0) {
732 cur_alloc_size = min(disk_num_bytes, root->fs_info->max_extent);
733 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
734 root->sectorsize, 0, alloc_hint,
738 em = alloc_extent_map(GFP_NOFS);
740 em->orig_start = em->start;
742 ram_size = ins.offset;
743 em->len = ins.offset;
745 em->block_start = ins.objectid;
746 em->block_len = ins.offset;
747 em->bdev = root->fs_info->fs_devices->latest_bdev;
748 set_bit(EXTENT_FLAG_PINNED, &em->flags);
751 spin_lock(&em_tree->lock);
752 ret = add_extent_mapping(em_tree, em);
753 spin_unlock(&em_tree->lock);
754 if (ret != -EEXIST) {
758 btrfs_drop_extent_cache(inode, start,
759 start + ram_size - 1, 0);
762 cur_alloc_size = ins.offset;
763 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
764 ram_size, cur_alloc_size, 0);
767 if (root->root_key.objectid ==
768 BTRFS_DATA_RELOC_TREE_OBJECTID) {
769 ret = btrfs_reloc_clone_csums(inode, start,
774 if (disk_num_bytes < cur_alloc_size)
777 /* we're not doing compressed IO, don't unlock the first
778 * page (which the caller expects to stay locked), don't
779 * clear any dirty bits and don't set any writeback bits
781 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
782 start, start + ram_size - 1,
783 locked_page, unlock, 1,
785 disk_num_bytes -= cur_alloc_size;
786 num_bytes -= cur_alloc_size;
787 alloc_hint = ins.objectid + ins.offset;
788 start += cur_alloc_size;
792 btrfs_end_transaction(trans, root);
798 * work queue call back to started compression on a file and pages
800 static noinline void async_cow_start(struct btrfs_work *work)
802 struct async_cow *async_cow;
804 async_cow = container_of(work, struct async_cow, work);
806 compress_file_range(async_cow->inode, async_cow->locked_page,
807 async_cow->start, async_cow->end, async_cow,
810 async_cow->inode = NULL;
814 * work queue call back to submit previously compressed pages
816 static noinline void async_cow_submit(struct btrfs_work *work)
818 struct async_cow *async_cow;
819 struct btrfs_root *root;
820 unsigned long nr_pages;
822 async_cow = container_of(work, struct async_cow, work);
824 root = async_cow->root;
825 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
828 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
830 if (atomic_read(&root->fs_info->async_delalloc_pages) <
832 waitqueue_active(&root->fs_info->async_submit_wait))
833 wake_up(&root->fs_info->async_submit_wait);
835 if (async_cow->inode)
836 submit_compressed_extents(async_cow->inode, async_cow);
839 static noinline void async_cow_free(struct btrfs_work *work)
841 struct async_cow *async_cow;
842 async_cow = container_of(work, struct async_cow, work);
846 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
847 u64 start, u64 end, int *page_started,
848 unsigned long *nr_written)
850 struct async_cow *async_cow;
851 struct btrfs_root *root = BTRFS_I(inode)->root;
852 unsigned long nr_pages;
854 int limit = 10 * 1024 * 1042;
856 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED |
857 EXTENT_DELALLOC, 1, 0, GFP_NOFS);
858 while (start < end) {
859 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
860 async_cow->inode = inode;
861 async_cow->root = root;
862 async_cow->locked_page = locked_page;
863 async_cow->start = start;
865 if (btrfs_test_flag(inode, NOCOMPRESS))
868 cur_end = min(end, start + 512 * 1024 - 1);
870 async_cow->end = cur_end;
871 INIT_LIST_HEAD(&async_cow->extents);
873 async_cow->work.func = async_cow_start;
874 async_cow->work.ordered_func = async_cow_submit;
875 async_cow->work.ordered_free = async_cow_free;
876 async_cow->work.flags = 0;
878 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
880 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
882 btrfs_queue_worker(&root->fs_info->delalloc_workers,
885 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
886 wait_event(root->fs_info->async_submit_wait,
887 (atomic_read(&root->fs_info->async_delalloc_pages) <
891 while (atomic_read(&root->fs_info->async_submit_draining) &&
892 atomic_read(&root->fs_info->async_delalloc_pages)) {
893 wait_event(root->fs_info->async_submit_wait,
894 (atomic_read(&root->fs_info->async_delalloc_pages) ==
898 *nr_written += nr_pages;
905 static noinline int csum_exist_in_range(struct btrfs_root *root,
906 u64 bytenr, u64 num_bytes)
909 struct btrfs_ordered_sum *sums;
912 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
913 bytenr + num_bytes - 1, &list);
914 if (ret == 0 && list_empty(&list))
917 while (!list_empty(&list)) {
918 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
919 list_del(&sums->list);
926 * when nowcow writeback call back. This checks for snapshots or COW copies
927 * of the extents that exist in the file, and COWs the file as required.
929 * If no cow copies or snapshots exist, we write directly to the existing
932 static noinline int run_delalloc_nocow(struct inode *inode,
933 struct page *locked_page,
934 u64 start, u64 end, int *page_started, int force,
935 unsigned long *nr_written)
937 struct btrfs_root *root = BTRFS_I(inode)->root;
938 struct btrfs_trans_handle *trans;
939 struct extent_buffer *leaf;
940 struct btrfs_path *path;
941 struct btrfs_file_extent_item *fi;
942 struct btrfs_key found_key;
955 path = btrfs_alloc_path();
957 trans = btrfs_join_transaction(root, 1);
963 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
966 if (ret > 0 && path->slots[0] > 0 && check_prev) {
967 leaf = path->nodes[0];
968 btrfs_item_key_to_cpu(leaf, &found_key,
970 if (found_key.objectid == inode->i_ino &&
971 found_key.type == BTRFS_EXTENT_DATA_KEY)
976 leaf = path->nodes[0];
977 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
978 ret = btrfs_next_leaf(root, path);
983 leaf = path->nodes[0];
989 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
991 if (found_key.objectid > inode->i_ino ||
992 found_key.type > BTRFS_EXTENT_DATA_KEY ||
993 found_key.offset > end)
996 if (found_key.offset > cur_offset) {
997 extent_end = found_key.offset;
1001 fi = btrfs_item_ptr(leaf, path->slots[0],
1002 struct btrfs_file_extent_item);
1003 extent_type = btrfs_file_extent_type(leaf, fi);
1005 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1006 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1007 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1008 extent_offset = btrfs_file_extent_offset(leaf, fi);
1009 extent_end = found_key.offset +
1010 btrfs_file_extent_num_bytes(leaf, fi);
1011 if (extent_end <= start) {
1015 if (disk_bytenr == 0)
1017 if (btrfs_file_extent_compression(leaf, fi) ||
1018 btrfs_file_extent_encryption(leaf, fi) ||
1019 btrfs_file_extent_other_encoding(leaf, fi))
1021 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1023 if (btrfs_extent_readonly(root, disk_bytenr))
1025 if (btrfs_cross_ref_exist(trans, root, inode->i_ino,
1027 extent_offset, disk_bytenr))
1029 disk_bytenr += extent_offset;
1030 disk_bytenr += cur_offset - found_key.offset;
1031 num_bytes = min(end + 1, extent_end) - cur_offset;
1033 * force cow if csum exists in the range.
1034 * this ensure that csum for a given extent are
1035 * either valid or do not exist.
1037 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1040 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1041 extent_end = found_key.offset +
1042 btrfs_file_extent_inline_len(leaf, fi);
1043 extent_end = ALIGN(extent_end, root->sectorsize);
1048 if (extent_end <= start) {
1053 if (cow_start == (u64)-1)
1054 cow_start = cur_offset;
1055 cur_offset = extent_end;
1056 if (cur_offset > end)
1062 btrfs_release_path(root, path);
1063 if (cow_start != (u64)-1) {
1064 ret = cow_file_range(inode, locked_page, cow_start,
1065 found_key.offset - 1, page_started,
1068 cow_start = (u64)-1;
1071 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1072 struct extent_map *em;
1073 struct extent_map_tree *em_tree;
1074 em_tree = &BTRFS_I(inode)->extent_tree;
1075 em = alloc_extent_map(GFP_NOFS);
1076 em->start = cur_offset;
1077 em->orig_start = em->start;
1078 em->len = num_bytes;
1079 em->block_len = num_bytes;
1080 em->block_start = disk_bytenr;
1081 em->bdev = root->fs_info->fs_devices->latest_bdev;
1082 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1084 spin_lock(&em_tree->lock);
1085 ret = add_extent_mapping(em_tree, em);
1086 spin_unlock(&em_tree->lock);
1087 if (ret != -EEXIST) {
1088 free_extent_map(em);
1091 btrfs_drop_extent_cache(inode, em->start,
1092 em->start + em->len - 1, 0);
1094 type = BTRFS_ORDERED_PREALLOC;
1096 type = BTRFS_ORDERED_NOCOW;
1099 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1100 num_bytes, num_bytes, type);
1103 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1104 cur_offset, cur_offset + num_bytes - 1,
1105 locked_page, 1, 1, 1, 0, 0, 0);
1106 cur_offset = extent_end;
1107 if (cur_offset > end)
1110 btrfs_release_path(root, path);
1112 if (cur_offset <= end && cow_start == (u64)-1)
1113 cow_start = cur_offset;
1114 if (cow_start != (u64)-1) {
1115 ret = cow_file_range(inode, locked_page, cow_start, end,
1116 page_started, nr_written, 1);
1120 ret = btrfs_end_transaction(trans, root);
1122 btrfs_free_path(path);
1127 * extent_io.c call back to do delayed allocation processing
1129 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1130 u64 start, u64 end, int *page_started,
1131 unsigned long *nr_written)
1134 struct btrfs_root *root = BTRFS_I(inode)->root;
1136 if (btrfs_test_flag(inode, NODATACOW))
1137 ret = run_delalloc_nocow(inode, locked_page, start, end,
1138 page_started, 1, nr_written);
1139 else if (btrfs_test_flag(inode, PREALLOC))
1140 ret = run_delalloc_nocow(inode, locked_page, start, end,
1141 page_started, 0, nr_written);
1142 else if (!btrfs_test_opt(root, COMPRESS))
1143 ret = cow_file_range(inode, locked_page, start, end,
1144 page_started, nr_written, 1);
1146 ret = cow_file_range_async(inode, locked_page, start, end,
1147 page_started, nr_written);
1152 * extent_io.c set_bit_hook, used to track delayed allocation
1153 * bytes in this file, and to maintain the list of inodes that
1154 * have pending delalloc work to be done.
1156 static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
1157 unsigned long old, unsigned long bits)
1160 * set_bit and clear bit hooks normally require _irqsave/restore
1161 * but in this case, we are only testeing for the DELALLOC
1162 * bit, which is only set or cleared with irqs on
1164 if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
1165 struct btrfs_root *root = BTRFS_I(inode)->root;
1166 btrfs_delalloc_reserve_space(root, inode, end - start + 1);
1167 spin_lock(&root->fs_info->delalloc_lock);
1168 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
1169 root->fs_info->delalloc_bytes += end - start + 1;
1170 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1171 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1172 &root->fs_info->delalloc_inodes);
1174 spin_unlock(&root->fs_info->delalloc_lock);
1180 * extent_io.c clear_bit_hook, see set_bit_hook for why
1182 static int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
1183 unsigned long old, unsigned long bits)
1186 * set_bit and clear bit hooks normally require _irqsave/restore
1187 * but in this case, we are only testeing for the DELALLOC
1188 * bit, which is only set or cleared with irqs on
1190 if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
1191 struct btrfs_root *root = BTRFS_I(inode)->root;
1193 spin_lock(&root->fs_info->delalloc_lock);
1194 if (end - start + 1 > root->fs_info->delalloc_bytes) {
1195 printk(KERN_INFO "btrfs warning: delalloc account "
1197 (unsigned long long)end - start + 1,
1198 (unsigned long long)
1199 root->fs_info->delalloc_bytes);
1200 btrfs_delalloc_free_space(root, inode, (u64)-1);
1201 root->fs_info->delalloc_bytes = 0;
1202 BTRFS_I(inode)->delalloc_bytes = 0;
1204 btrfs_delalloc_free_space(root, inode,
1206 root->fs_info->delalloc_bytes -= end - start + 1;
1207 BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
1209 if (BTRFS_I(inode)->delalloc_bytes == 0 &&
1210 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1211 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1213 spin_unlock(&root->fs_info->delalloc_lock);
1219 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1220 * we don't create bios that span stripes or chunks
1222 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1223 size_t size, struct bio *bio,
1224 unsigned long bio_flags)
1226 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1227 struct btrfs_mapping_tree *map_tree;
1228 u64 logical = (u64)bio->bi_sector << 9;
1233 if (bio_flags & EXTENT_BIO_COMPRESSED)
1236 length = bio->bi_size;
1237 map_tree = &root->fs_info->mapping_tree;
1238 map_length = length;
1239 ret = btrfs_map_block(map_tree, READ, logical,
1240 &map_length, NULL, 0);
1242 if (map_length < length + size)
1248 * in order to insert checksums into the metadata in large chunks,
1249 * we wait until bio submission time. All the pages in the bio are
1250 * checksummed and sums are attached onto the ordered extent record.
1252 * At IO completion time the cums attached on the ordered extent record
1253 * are inserted into the btree
1255 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1256 struct bio *bio, int mirror_num,
1257 unsigned long bio_flags)
1259 struct btrfs_root *root = BTRFS_I(inode)->root;
1262 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1268 * in order to insert checksums into the metadata in large chunks,
1269 * we wait until bio submission time. All the pages in the bio are
1270 * checksummed and sums are attached onto the ordered extent record.
1272 * At IO completion time the cums attached on the ordered extent record
1273 * are inserted into the btree
1275 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1276 int mirror_num, unsigned long bio_flags)
1278 struct btrfs_root *root = BTRFS_I(inode)->root;
1279 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1283 * extent_io.c submission hook. This does the right thing for csum calculation
1284 * on write, or reading the csums from the tree before a read
1286 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1287 int mirror_num, unsigned long bio_flags)
1289 struct btrfs_root *root = BTRFS_I(inode)->root;
1293 skip_sum = btrfs_test_flag(inode, NODATASUM);
1295 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1298 if (!(rw & (1 << BIO_RW))) {
1299 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1300 return btrfs_submit_compressed_read(inode, bio,
1301 mirror_num, bio_flags);
1302 } else if (!skip_sum)
1303 btrfs_lookup_bio_sums(root, inode, bio, NULL);
1305 } else if (!skip_sum) {
1306 /* csum items have already been cloned */
1307 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1309 /* we're doing a write, do the async checksumming */
1310 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1311 inode, rw, bio, mirror_num,
1312 bio_flags, __btrfs_submit_bio_start,
1313 __btrfs_submit_bio_done);
1317 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1321 * given a list of ordered sums record them in the inode. This happens
1322 * at IO completion time based on sums calculated at bio submission time.
1324 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1325 struct inode *inode, u64 file_offset,
1326 struct list_head *list)
1328 struct btrfs_ordered_sum *sum;
1330 btrfs_set_trans_block_group(trans, inode);
1332 list_for_each_entry(sum, list, list) {
1333 btrfs_csum_file_blocks(trans,
1334 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1339 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
1341 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1343 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1347 /* see btrfs_writepage_start_hook for details on why this is required */
1348 struct btrfs_writepage_fixup {
1350 struct btrfs_work work;
1353 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1355 struct btrfs_writepage_fixup *fixup;
1356 struct btrfs_ordered_extent *ordered;
1358 struct inode *inode;
1362 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1366 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1367 ClearPageChecked(page);
1371 inode = page->mapping->host;
1372 page_start = page_offset(page);
1373 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1375 lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
1377 /* already ordered? We're done */
1378 if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
1379 EXTENT_ORDERED, 0)) {
1383 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1385 unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
1386 page_end, GFP_NOFS);
1388 btrfs_start_ordered_extent(inode, ordered, 1);
1392 btrfs_set_extent_delalloc(inode, page_start, page_end);
1393 ClearPageChecked(page);
1395 unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
1398 page_cache_release(page);
1402 * There are a few paths in the higher layers of the kernel that directly
1403 * set the page dirty bit without asking the filesystem if it is a
1404 * good idea. This causes problems because we want to make sure COW
1405 * properly happens and the data=ordered rules are followed.
1407 * In our case any range that doesn't have the ORDERED bit set
1408 * hasn't been properly setup for IO. We kick off an async process
1409 * to fix it up. The async helper will wait for ordered extents, set
1410 * the delalloc bit and make it safe to write the page.
1412 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1414 struct inode *inode = page->mapping->host;
1415 struct btrfs_writepage_fixup *fixup;
1416 struct btrfs_root *root = BTRFS_I(inode)->root;
1419 ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
1424 if (PageChecked(page))
1427 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1431 SetPageChecked(page);
1432 page_cache_get(page);
1433 fixup->work.func = btrfs_writepage_fixup_worker;
1435 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1439 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1440 struct inode *inode, u64 file_pos,
1441 u64 disk_bytenr, u64 disk_num_bytes,
1442 u64 num_bytes, u64 ram_bytes,
1444 u8 compression, u8 encryption,
1445 u16 other_encoding, int extent_type)
1447 struct btrfs_root *root = BTRFS_I(inode)->root;
1448 struct btrfs_file_extent_item *fi;
1449 struct btrfs_path *path;
1450 struct extent_buffer *leaf;
1451 struct btrfs_key ins;
1455 path = btrfs_alloc_path();
1458 path->leave_spinning = 1;
1459 ret = btrfs_drop_extents(trans, root, inode, file_pos,
1460 file_pos + num_bytes, locked_end,
1464 ins.objectid = inode->i_ino;
1465 ins.offset = file_pos;
1466 ins.type = BTRFS_EXTENT_DATA_KEY;
1467 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1469 leaf = path->nodes[0];
1470 fi = btrfs_item_ptr(leaf, path->slots[0],
1471 struct btrfs_file_extent_item);
1472 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1473 btrfs_set_file_extent_type(leaf, fi, extent_type);
1474 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1475 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1476 btrfs_set_file_extent_offset(leaf, fi, 0);
1477 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1478 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1479 btrfs_set_file_extent_compression(leaf, fi, compression);
1480 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1481 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1483 btrfs_unlock_up_safe(path, 1);
1484 btrfs_set_lock_blocking(leaf);
1486 btrfs_mark_buffer_dirty(leaf);
1488 inode_add_bytes(inode, num_bytes);
1489 btrfs_drop_extent_cache(inode, file_pos, file_pos + num_bytes - 1, 0);
1491 ins.objectid = disk_bytenr;
1492 ins.offset = disk_num_bytes;
1493 ins.type = BTRFS_EXTENT_ITEM_KEY;
1494 ret = btrfs_alloc_reserved_file_extent(trans, root,
1495 root->root_key.objectid,
1496 inode->i_ino, file_pos, &ins);
1498 btrfs_free_path(path);
1504 * helper function for btrfs_finish_ordered_io, this
1505 * just reads in some of the csum leaves to prime them into ram
1506 * before we start the transaction. It limits the amount of btree
1507 * reads required while inside the transaction.
1509 static noinline void reada_csum(struct btrfs_root *root,
1510 struct btrfs_path *path,
1511 struct btrfs_ordered_extent *ordered_extent)
1513 struct btrfs_ordered_sum *sum;
1516 sum = list_entry(ordered_extent->list.next, struct btrfs_ordered_sum,
1518 bytenr = sum->sums[0].bytenr;
1521 * we don't care about the results, the point of this search is
1522 * just to get the btree leaves into ram
1524 btrfs_lookup_csum(NULL, root->fs_info->csum_root, path, bytenr, 0);
1527 /* as ordered data IO finishes, this gets called so we can finish
1528 * an ordered extent if the range of bytes in the file it covers are
1531 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1533 struct btrfs_root *root = BTRFS_I(inode)->root;
1534 struct btrfs_trans_handle *trans;
1535 struct btrfs_ordered_extent *ordered_extent = NULL;
1536 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1537 struct btrfs_path *path;
1541 ret = btrfs_dec_test_ordered_pending(inode, start, end - start + 1);
1546 * before we join the transaction, try to do some of our IO.
1547 * This will limit the amount of IO that we have to do with
1548 * the transaction running. We're unlikely to need to do any
1549 * IO if the file extents are new, the disk_i_size checks
1550 * covers the most common case.
1552 if (start < BTRFS_I(inode)->disk_i_size) {
1553 path = btrfs_alloc_path();
1555 ret = btrfs_lookup_file_extent(NULL, root, path,
1558 ordered_extent = btrfs_lookup_ordered_extent(inode,
1560 if (!list_empty(&ordered_extent->list)) {
1561 btrfs_release_path(root, path);
1562 reada_csum(root, path, ordered_extent);
1564 btrfs_free_path(path);
1568 trans = btrfs_join_transaction(root, 1);
1570 if (!ordered_extent)
1571 ordered_extent = btrfs_lookup_ordered_extent(inode, start);
1572 BUG_ON(!ordered_extent);
1573 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags))
1576 lock_extent(io_tree, ordered_extent->file_offset,
1577 ordered_extent->file_offset + ordered_extent->len - 1,
1580 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1582 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1584 ret = btrfs_mark_extent_written(trans, root, inode,
1585 ordered_extent->file_offset,
1586 ordered_extent->file_offset +
1587 ordered_extent->len);
1590 ret = insert_reserved_file_extent(trans, inode,
1591 ordered_extent->file_offset,
1592 ordered_extent->start,
1593 ordered_extent->disk_len,
1594 ordered_extent->len,
1595 ordered_extent->len,
1596 ordered_extent->file_offset +
1597 ordered_extent->len,
1599 BTRFS_FILE_EXTENT_REG);
1602 unlock_extent(io_tree, ordered_extent->file_offset,
1603 ordered_extent->file_offset + ordered_extent->len - 1,
1606 add_pending_csums(trans, inode, ordered_extent->file_offset,
1607 &ordered_extent->list);
1609 mutex_lock(&BTRFS_I(inode)->extent_mutex);
1610 btrfs_ordered_update_i_size(inode, ordered_extent);
1611 btrfs_update_inode(trans, root, inode);
1612 btrfs_remove_ordered_extent(inode, ordered_extent);
1613 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
1616 btrfs_put_ordered_extent(ordered_extent);
1617 /* once for the tree */
1618 btrfs_put_ordered_extent(ordered_extent);
1620 btrfs_end_transaction(trans, root);
1624 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1625 struct extent_state *state, int uptodate)
1627 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1631 * When IO fails, either with EIO or csum verification fails, we
1632 * try other mirrors that might have a good copy of the data. This
1633 * io_failure_record is used to record state as we go through all the
1634 * mirrors. If another mirror has good data, the page is set up to date
1635 * and things continue. If a good mirror can't be found, the original
1636 * bio end_io callback is called to indicate things have failed.
1638 struct io_failure_record {
1643 unsigned long bio_flags;
1647 static int btrfs_io_failed_hook(struct bio *failed_bio,
1648 struct page *page, u64 start, u64 end,
1649 struct extent_state *state)
1651 struct io_failure_record *failrec = NULL;
1653 struct extent_map *em;
1654 struct inode *inode = page->mapping->host;
1655 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1656 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1663 ret = get_state_private(failure_tree, start, &private);
1665 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
1668 failrec->start = start;
1669 failrec->len = end - start + 1;
1670 failrec->last_mirror = 0;
1671 failrec->bio_flags = 0;
1673 spin_lock(&em_tree->lock);
1674 em = lookup_extent_mapping(em_tree, start, failrec->len);
1675 if (em->start > start || em->start + em->len < start) {
1676 free_extent_map(em);
1679 spin_unlock(&em_tree->lock);
1681 if (!em || IS_ERR(em)) {
1685 logical = start - em->start;
1686 logical = em->block_start + logical;
1687 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
1688 logical = em->block_start;
1689 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
1691 failrec->logical = logical;
1692 free_extent_map(em);
1693 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
1694 EXTENT_DIRTY, GFP_NOFS);
1695 set_state_private(failure_tree, start,
1696 (u64)(unsigned long)failrec);
1698 failrec = (struct io_failure_record *)(unsigned long)private;
1700 num_copies = btrfs_num_copies(
1701 &BTRFS_I(inode)->root->fs_info->mapping_tree,
1702 failrec->logical, failrec->len);
1703 failrec->last_mirror++;
1705 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1706 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1709 if (state && state->start != failrec->start)
1711 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1713 if (!state || failrec->last_mirror > num_copies) {
1714 set_state_private(failure_tree, failrec->start, 0);
1715 clear_extent_bits(failure_tree, failrec->start,
1716 failrec->start + failrec->len - 1,
1717 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1721 bio = bio_alloc(GFP_NOFS, 1);
1722 bio->bi_private = state;
1723 bio->bi_end_io = failed_bio->bi_end_io;
1724 bio->bi_sector = failrec->logical >> 9;
1725 bio->bi_bdev = failed_bio->bi_bdev;
1728 bio_add_page(bio, page, failrec->len, start - page_offset(page));
1729 if (failed_bio->bi_rw & (1 << BIO_RW))
1734 BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
1735 failrec->last_mirror,
1736 failrec->bio_flags);
1741 * each time an IO finishes, we do a fast check in the IO failure tree
1742 * to see if we need to process or clean up an io_failure_record
1744 static int btrfs_clean_io_failures(struct inode *inode, u64 start)
1747 u64 private_failure;
1748 struct io_failure_record *failure;
1752 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1753 (u64)-1, 1, EXTENT_DIRTY)) {
1754 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
1755 start, &private_failure);
1757 failure = (struct io_failure_record *)(unsigned long)
1759 set_state_private(&BTRFS_I(inode)->io_failure_tree,
1761 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
1763 failure->start + failure->len - 1,
1764 EXTENT_DIRTY | EXTENT_LOCKED,
1773 * when reads are done, we need to check csums to verify the data is correct
1774 * if there's a match, we allow the bio to finish. If not, we go through
1775 * the io_failure_record routines to find good copies
1777 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1778 struct extent_state *state)
1780 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1781 struct inode *inode = page->mapping->host;
1782 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1784 u64 private = ~(u32)0;
1786 struct btrfs_root *root = BTRFS_I(inode)->root;
1789 if (PageChecked(page)) {
1790 ClearPageChecked(page);
1793 if (btrfs_test_flag(inode, NODATASUM))
1796 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1797 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1)) {
1798 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1803 if (state && state->start == start) {
1804 private = state->private;
1807 ret = get_state_private(io_tree, start, &private);
1809 kaddr = kmap_atomic(page, KM_USER0);
1813 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
1814 btrfs_csum_final(csum, (char *)&csum);
1815 if (csum != private)
1818 kunmap_atomic(kaddr, KM_USER0);
1820 /* if the io failure tree for this inode is non-empty,
1821 * check to see if we've recovered from a failed IO
1823 btrfs_clean_io_failures(inode, start);
1827 if (printk_ratelimit()) {
1828 printk(KERN_INFO "btrfs csum failed ino %lu off %llu csum %u "
1829 "private %llu\n", page->mapping->host->i_ino,
1830 (unsigned long long)start, csum,
1831 (unsigned long long)private);
1833 memset(kaddr + offset, 1, end - start + 1);
1834 flush_dcache_page(page);
1835 kunmap_atomic(kaddr, KM_USER0);
1842 * This creates an orphan entry for the given inode in case something goes
1843 * wrong in the middle of an unlink/truncate.
1845 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
1847 struct btrfs_root *root = BTRFS_I(inode)->root;
1850 spin_lock(&root->list_lock);
1852 /* already on the orphan list, we're good */
1853 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
1854 spin_unlock(&root->list_lock);
1858 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
1860 spin_unlock(&root->list_lock);
1863 * insert an orphan item to track this unlinked/truncated file
1865 ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
1871 * We have done the truncate/delete so we can go ahead and remove the orphan
1872 * item for this particular inode.
1874 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
1876 struct btrfs_root *root = BTRFS_I(inode)->root;
1879 spin_lock(&root->list_lock);
1881 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
1882 spin_unlock(&root->list_lock);
1886 list_del_init(&BTRFS_I(inode)->i_orphan);
1888 spin_unlock(&root->list_lock);
1892 spin_unlock(&root->list_lock);
1894 ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
1900 * this cleans up any orphans that may be left on the list from the last use
1903 void btrfs_orphan_cleanup(struct btrfs_root *root)
1905 struct btrfs_path *path;
1906 struct extent_buffer *leaf;
1907 struct btrfs_item *item;
1908 struct btrfs_key key, found_key;
1909 struct btrfs_trans_handle *trans;
1910 struct inode *inode;
1911 int ret = 0, nr_unlink = 0, nr_truncate = 0;
1913 path = btrfs_alloc_path();
1918 key.objectid = BTRFS_ORPHAN_OBJECTID;
1919 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1920 key.offset = (u64)-1;
1924 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1926 printk(KERN_ERR "Error searching slot for orphan: %d"
1932 * if ret == 0 means we found what we were searching for, which
1933 * is weird, but possible, so only screw with path if we didnt
1934 * find the key and see if we have stuff that matches
1937 if (path->slots[0] == 0)
1942 /* pull out the item */
1943 leaf = path->nodes[0];
1944 item = btrfs_item_nr(leaf, path->slots[0]);
1945 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1947 /* make sure the item matches what we want */
1948 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
1950 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
1953 /* release the path since we're done with it */
1954 btrfs_release_path(root, path);
1957 * this is where we are basically btrfs_lookup, without the
1958 * crossing root thing. we store the inode number in the
1959 * offset of the orphan item.
1961 found_key.objectid = found_key.offset;
1962 found_key.type = BTRFS_INODE_ITEM_KEY;
1963 found_key.offset = 0;
1964 inode = btrfs_iget(root->fs_info->sb, &found_key, root);
1969 * add this inode to the orphan list so btrfs_orphan_del does
1970 * the proper thing when we hit it
1972 spin_lock(&root->list_lock);
1973 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
1974 spin_unlock(&root->list_lock);
1977 * if this is a bad inode, means we actually succeeded in
1978 * removing the inode, but not the orphan record, which means
1979 * we need to manually delete the orphan since iput will just
1980 * do a destroy_inode
1982 if (is_bad_inode(inode)) {
1983 trans = btrfs_start_transaction(root, 1);
1984 btrfs_orphan_del(trans, inode);
1985 btrfs_end_transaction(trans, root);
1990 /* if we have links, this was a truncate, lets do that */
1991 if (inode->i_nlink) {
1993 btrfs_truncate(inode);
1998 /* this will do delete_inode and everything for us */
2003 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2005 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2007 btrfs_free_path(path);
2011 * very simple check to peek ahead in the leaf looking for xattrs. If we
2012 * don't find any xattrs, we know there can't be any acls.
2014 * slot is the slot the inode is in, objectid is the objectid of the inode
2016 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2017 int slot, u64 objectid)
2019 u32 nritems = btrfs_header_nritems(leaf);
2020 struct btrfs_key found_key;
2024 while (slot < nritems) {
2025 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2027 /* we found a different objectid, there must not be acls */
2028 if (found_key.objectid != objectid)
2031 /* we found an xattr, assume we've got an acl */
2032 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2036 * we found a key greater than an xattr key, there can't
2037 * be any acls later on
2039 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2046 * it goes inode, inode backrefs, xattrs, extents,
2047 * so if there are a ton of hard links to an inode there can
2048 * be a lot of backrefs. Don't waste time searching too hard,
2049 * this is just an optimization
2054 /* we hit the end of the leaf before we found an xattr or
2055 * something larger than an xattr. We have to assume the inode
2062 * read an inode from the btree into the in-memory inode
2064 static void btrfs_read_locked_inode(struct inode *inode)
2066 struct btrfs_path *path;
2067 struct extent_buffer *leaf;
2068 struct btrfs_inode_item *inode_item;
2069 struct btrfs_timespec *tspec;
2070 struct btrfs_root *root = BTRFS_I(inode)->root;
2071 struct btrfs_key location;
2073 u64 alloc_group_block;
2077 path = btrfs_alloc_path();
2079 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2081 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2085 leaf = path->nodes[0];
2086 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2087 struct btrfs_inode_item);
2089 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2090 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
2091 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2092 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2093 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2095 tspec = btrfs_inode_atime(inode_item);
2096 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2097 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2099 tspec = btrfs_inode_mtime(inode_item);
2100 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2101 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2103 tspec = btrfs_inode_ctime(inode_item);
2104 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2105 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2107 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2108 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2109 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2110 inode->i_generation = BTRFS_I(inode)->generation;
2112 rdev = btrfs_inode_rdev(leaf, inode_item);
2114 BTRFS_I(inode)->index_cnt = (u64)-1;
2115 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2117 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
2120 * try to precache a NULL acl entry for files that don't have
2121 * any xattrs or acls
2123 maybe_acls = acls_after_inode_item(leaf, path->slots[0], inode->i_ino);
2125 BTRFS_I(inode)->i_acl = NULL;
2126 BTRFS_I(inode)->i_default_acl = NULL;
2129 BTRFS_I(inode)->block_group = btrfs_find_block_group(root, 0,
2130 alloc_group_block, 0);
2131 btrfs_free_path(path);
2134 switch (inode->i_mode & S_IFMT) {
2136 inode->i_mapping->a_ops = &btrfs_aops;
2137 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2138 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2139 inode->i_fop = &btrfs_file_operations;
2140 inode->i_op = &btrfs_file_inode_operations;
2143 inode->i_fop = &btrfs_dir_file_operations;
2144 if (root == root->fs_info->tree_root)
2145 inode->i_op = &btrfs_dir_ro_inode_operations;
2147 inode->i_op = &btrfs_dir_inode_operations;
2150 inode->i_op = &btrfs_symlink_inode_operations;
2151 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2152 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2155 inode->i_op = &btrfs_special_inode_operations;
2156 init_special_inode(inode, inode->i_mode, rdev);
2162 btrfs_free_path(path);
2163 make_bad_inode(inode);
2167 * given a leaf and an inode, copy the inode fields into the leaf
2169 static void fill_inode_item(struct btrfs_trans_handle *trans,
2170 struct extent_buffer *leaf,
2171 struct btrfs_inode_item *item,
2172 struct inode *inode)
2174 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2175 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2176 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2177 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2178 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2180 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2181 inode->i_atime.tv_sec);
2182 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2183 inode->i_atime.tv_nsec);
2185 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2186 inode->i_mtime.tv_sec);
2187 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2188 inode->i_mtime.tv_nsec);
2190 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2191 inode->i_ctime.tv_sec);
2192 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2193 inode->i_ctime.tv_nsec);
2195 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2196 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2197 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2198 btrfs_set_inode_transid(leaf, item, trans->transid);
2199 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2200 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2201 btrfs_set_inode_block_group(leaf, item, BTRFS_I(inode)->block_group);
2205 * copy everything in the in-memory inode into the btree.
2207 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2208 struct btrfs_root *root, struct inode *inode)
2210 struct btrfs_inode_item *inode_item;
2211 struct btrfs_path *path;
2212 struct extent_buffer *leaf;
2215 path = btrfs_alloc_path();
2217 path->leave_spinning = 1;
2218 ret = btrfs_lookup_inode(trans, root, path,
2219 &BTRFS_I(inode)->location, 1);
2226 btrfs_unlock_up_safe(path, 1);
2227 leaf = path->nodes[0];
2228 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2229 struct btrfs_inode_item);
2231 fill_inode_item(trans, leaf, inode_item, inode);
2232 btrfs_mark_buffer_dirty(leaf);
2233 btrfs_set_inode_last_trans(trans, inode);
2236 btrfs_free_path(path);
2242 * unlink helper that gets used here in inode.c and in the tree logging
2243 * recovery code. It remove a link in a directory with a given name, and
2244 * also drops the back refs in the inode to the directory
2246 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2247 struct btrfs_root *root,
2248 struct inode *dir, struct inode *inode,
2249 const char *name, int name_len)
2251 struct btrfs_path *path;
2253 struct extent_buffer *leaf;
2254 struct btrfs_dir_item *di;
2255 struct btrfs_key key;
2258 path = btrfs_alloc_path();
2264 path->leave_spinning = 1;
2265 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
2266 name, name_len, -1);
2275 leaf = path->nodes[0];
2276 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2277 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2280 btrfs_release_path(root, path);
2282 ret = btrfs_del_inode_ref(trans, root, name, name_len,
2284 dir->i_ino, &index);
2286 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2287 "inode %lu parent %lu\n", name_len, name,
2288 inode->i_ino, dir->i_ino);
2292 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
2293 index, name, name_len, -1);
2302 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2303 btrfs_release_path(root, path);
2305 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2307 BUG_ON(ret != 0 && ret != -ENOENT);
2309 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2313 btrfs_free_path(path);
2317 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2318 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2319 btrfs_update_inode(trans, root, dir);
2320 btrfs_drop_nlink(inode);
2321 ret = btrfs_update_inode(trans, root, inode);
2322 dir->i_sb->s_dirt = 1;
2327 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2329 struct btrfs_root *root;
2330 struct btrfs_trans_handle *trans;
2331 struct inode *inode = dentry->d_inode;
2333 unsigned long nr = 0;
2335 root = BTRFS_I(dir)->root;
2337 trans = btrfs_start_transaction(root, 1);
2339 btrfs_set_trans_block_group(trans, dir);
2341 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
2343 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2344 dentry->d_name.name, dentry->d_name.len);
2346 if (inode->i_nlink == 0)
2347 ret = btrfs_orphan_add(trans, inode);
2349 nr = trans->blocks_used;
2351 btrfs_end_transaction_throttle(trans, root);
2352 btrfs_btree_balance_dirty(root, nr);
2356 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
2358 struct inode *inode = dentry->d_inode;
2361 struct btrfs_root *root = BTRFS_I(dir)->root;
2362 struct btrfs_trans_handle *trans;
2363 unsigned long nr = 0;
2366 * the FIRST_FREE_OBJECTID check makes sure we don't try to rmdir
2367 * the root of a subvolume or snapshot
2369 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
2370 inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
2374 trans = btrfs_start_transaction(root, 1);
2375 btrfs_set_trans_block_group(trans, dir);
2377 err = btrfs_orphan_add(trans, inode);
2381 /* now the directory is empty */
2382 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2383 dentry->d_name.name, dentry->d_name.len);
2385 btrfs_i_size_write(inode, 0);
2388 nr = trans->blocks_used;
2389 ret = btrfs_end_transaction_throttle(trans, root);
2390 btrfs_btree_balance_dirty(root, nr);
2399 * when truncating bytes in a file, it is possible to avoid reading
2400 * the leaves that contain only checksum items. This can be the
2401 * majority of the IO required to delete a large file, but it must
2402 * be done carefully.
2404 * The keys in the level just above the leaves are checked to make sure
2405 * the lowest key in a given leaf is a csum key, and starts at an offset
2406 * after the new size.
2408 * Then the key for the next leaf is checked to make sure it also has
2409 * a checksum item for the same file. If it does, we know our target leaf
2410 * contains only checksum items, and it can be safely freed without reading
2413 * This is just an optimization targeted at large files. It may do
2414 * nothing. It will return 0 unless things went badly.
2416 static noinline int drop_csum_leaves(struct btrfs_trans_handle *trans,
2417 struct btrfs_root *root,
2418 struct btrfs_path *path,
2419 struct inode *inode, u64 new_size)
2421 struct btrfs_key key;
2424 struct btrfs_key found_key;
2425 struct btrfs_key other_key;
2426 struct btrfs_leaf_ref *ref;
2430 path->lowest_level = 1;
2431 key.objectid = inode->i_ino;
2432 key.type = BTRFS_CSUM_ITEM_KEY;
2433 key.offset = new_size;
2435 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2439 if (path->nodes[1] == NULL) {
2444 btrfs_node_key_to_cpu(path->nodes[1], &found_key, path->slots[1]);
2445 nritems = btrfs_header_nritems(path->nodes[1]);
2450 if (path->slots[1] >= nritems)
2453 /* did we find a key greater than anything we want to delete? */
2454 if (found_key.objectid > inode->i_ino ||
2455 (found_key.objectid == inode->i_ino && found_key.type > key.type))
2458 /* we check the next key in the node to make sure the leave contains
2459 * only checksum items. This comparison doesn't work if our
2460 * leaf is the last one in the node
2462 if (path->slots[1] + 1 >= nritems) {
2464 /* search forward from the last key in the node, this
2465 * will bring us into the next node in the tree
2467 btrfs_node_key_to_cpu(path->nodes[1], &found_key, nritems - 1);
2469 /* unlikely, but we inc below, so check to be safe */
2470 if (found_key.offset == (u64)-1)
2473 /* search_forward needs a path with locks held, do the
2474 * search again for the original key. It is possible
2475 * this will race with a balance and return a path that
2476 * we could modify, but this drop is just an optimization
2477 * and is allowed to miss some leaves.
2479 btrfs_release_path(root, path);
2482 /* setup a max key for search_forward */
2483 other_key.offset = (u64)-1;
2484 other_key.type = key.type;
2485 other_key.objectid = key.objectid;
2487 path->keep_locks = 1;
2488 ret = btrfs_search_forward(root, &found_key, &other_key,
2490 path->keep_locks = 0;
2491 if (ret || found_key.objectid != key.objectid ||
2492 found_key.type != key.type) {
2497 key.offset = found_key.offset;
2498 btrfs_release_path(root, path);
2503 /* we know there's one more slot after us in the tree,
2504 * read that key so we can verify it is also a checksum item
2506 btrfs_node_key_to_cpu(path->nodes[1], &other_key, path->slots[1] + 1);
2508 if (found_key.objectid < inode->i_ino)
2511 if (found_key.type != key.type || found_key.offset < new_size)
2515 * if the key for the next leaf isn't a csum key from this objectid,
2516 * we can't be sure there aren't good items inside this leaf.
2519 if (other_key.objectid != inode->i_ino || other_key.type != key.type)
2522 leaf_start = btrfs_node_blockptr(path->nodes[1], path->slots[1]);
2523 leaf_gen = btrfs_node_ptr_generation(path->nodes[1], path->slots[1]);
2525 * it is safe to delete this leaf, it contains only
2526 * csum items from this inode at an offset >= new_size
2528 ret = btrfs_del_leaf(trans, root, path, leaf_start);
2531 if (root->ref_cows && leaf_gen < trans->transid) {
2532 ref = btrfs_alloc_leaf_ref(root, 0);
2534 ref->root_gen = root->root_key.offset;
2535 ref->bytenr = leaf_start;
2537 ref->generation = leaf_gen;
2540 btrfs_sort_leaf_ref(ref);
2542 ret = btrfs_add_leaf_ref(root, ref, 0);
2544 btrfs_free_leaf_ref(root, ref);
2550 btrfs_release_path(root, path);
2552 if (other_key.objectid == inode->i_ino &&
2553 other_key.type == key.type && other_key.offset > key.offset) {
2554 key.offset = other_key.offset;
2560 /* fixup any changes we've made to the path */
2561 path->lowest_level = 0;
2562 path->keep_locks = 0;
2563 btrfs_release_path(root, path);
2570 * this can truncate away extent items, csum items and directory items.
2571 * It starts at a high offset and removes keys until it can't find
2572 * any higher than new_size
2574 * csum items that cross the new i_size are truncated to the new size
2577 * min_type is the minimum key type to truncate down to. If set to 0, this
2578 * will kill all the items on this inode, including the INODE_ITEM_KEY.
2580 noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
2581 struct btrfs_root *root,
2582 struct inode *inode,
2583 u64 new_size, u32 min_type)
2586 struct btrfs_path *path;
2587 struct btrfs_key key;
2588 struct btrfs_key found_key;
2589 u32 found_type = (u8)-1;
2590 struct extent_buffer *leaf;
2591 struct btrfs_file_extent_item *fi;
2592 u64 extent_start = 0;
2593 u64 extent_num_bytes = 0;
2594 u64 extent_offset = 0;
2598 int pending_del_nr = 0;
2599 int pending_del_slot = 0;
2600 int extent_type = -1;
2602 u64 mask = root->sectorsize - 1;
2605 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
2606 path = btrfs_alloc_path();
2610 /* FIXME, add redo link to tree so we don't leak on crash */
2611 key.objectid = inode->i_ino;
2612 key.offset = (u64)-1;
2616 path->leave_spinning = 1;
2617 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2622 /* there are no items in the tree for us to truncate, we're
2625 if (path->slots[0] == 0) {
2634 leaf = path->nodes[0];
2635 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2636 found_type = btrfs_key_type(&found_key);
2639 if (found_key.objectid != inode->i_ino)
2642 if (found_type < min_type)
2645 item_end = found_key.offset;
2646 if (found_type == BTRFS_EXTENT_DATA_KEY) {
2647 fi = btrfs_item_ptr(leaf, path->slots[0],
2648 struct btrfs_file_extent_item);
2649 extent_type = btrfs_file_extent_type(leaf, fi);
2650 encoding = btrfs_file_extent_compression(leaf, fi);
2651 encoding |= btrfs_file_extent_encryption(leaf, fi);
2652 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
2654 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
2656 btrfs_file_extent_num_bytes(leaf, fi);
2657 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
2658 item_end += btrfs_file_extent_inline_len(leaf,
2663 if (item_end < new_size) {
2664 if (found_type == BTRFS_DIR_ITEM_KEY)
2665 found_type = BTRFS_INODE_ITEM_KEY;
2666 else if (found_type == BTRFS_EXTENT_ITEM_KEY)
2667 found_type = BTRFS_EXTENT_DATA_KEY;
2668 else if (found_type == BTRFS_EXTENT_DATA_KEY)
2669 found_type = BTRFS_XATTR_ITEM_KEY;
2670 else if (found_type == BTRFS_XATTR_ITEM_KEY)
2671 found_type = BTRFS_INODE_REF_KEY;
2672 else if (found_type)
2676 btrfs_set_key_type(&key, found_type);
2679 if (found_key.offset >= new_size)
2685 /* FIXME, shrink the extent if the ref count is only 1 */
2686 if (found_type != BTRFS_EXTENT_DATA_KEY)
2689 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
2691 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
2692 if (!del_item && !encoding) {
2693 u64 orig_num_bytes =
2694 btrfs_file_extent_num_bytes(leaf, fi);
2695 extent_num_bytes = new_size -
2696 found_key.offset + root->sectorsize - 1;
2697 extent_num_bytes = extent_num_bytes &
2698 ~((u64)root->sectorsize - 1);
2699 btrfs_set_file_extent_num_bytes(leaf, fi,
2701 num_dec = (orig_num_bytes -
2703 if (root->ref_cows && extent_start != 0)
2704 inode_sub_bytes(inode, num_dec);
2705 btrfs_mark_buffer_dirty(leaf);
2708 btrfs_file_extent_disk_num_bytes(leaf,
2710 extent_offset = found_key.offset -
2711 btrfs_file_extent_offset(leaf, fi);
2713 /* FIXME blocksize != 4096 */
2714 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
2715 if (extent_start != 0) {
2718 inode_sub_bytes(inode, num_dec);
2721 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
2723 * we can't truncate inline items that have had
2727 btrfs_file_extent_compression(leaf, fi) == 0 &&
2728 btrfs_file_extent_encryption(leaf, fi) == 0 &&
2729 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
2730 u32 size = new_size - found_key.offset;
2732 if (root->ref_cows) {
2733 inode_sub_bytes(inode, item_end + 1 -
2737 btrfs_file_extent_calc_inline_size(size);
2738 ret = btrfs_truncate_item(trans, root, path,
2741 } else if (root->ref_cows) {
2742 inode_sub_bytes(inode, item_end + 1 -
2748 if (!pending_del_nr) {
2749 /* no pending yet, add ourselves */
2750 pending_del_slot = path->slots[0];
2752 } else if (pending_del_nr &&
2753 path->slots[0] + 1 == pending_del_slot) {
2754 /* hop on the pending chunk */
2756 pending_del_slot = path->slots[0];
2763 if (found_extent && root->ref_cows) {
2764 btrfs_set_path_blocking(path);
2765 ret = btrfs_free_extent(trans, root, extent_start,
2766 extent_num_bytes, 0,
2767 btrfs_header_owner(leaf),
2768 inode->i_ino, extent_offset);
2772 if (path->slots[0] == 0) {
2775 btrfs_release_path(root, path);
2776 if (found_type == BTRFS_INODE_ITEM_KEY)
2782 if (pending_del_nr &&
2783 path->slots[0] + 1 != pending_del_slot) {
2784 struct btrfs_key debug;
2786 btrfs_item_key_to_cpu(path->nodes[0], &debug,
2788 ret = btrfs_del_items(trans, root, path,
2793 btrfs_release_path(root, path);
2794 if (found_type == BTRFS_INODE_ITEM_KEY)
2801 if (pending_del_nr) {
2802 ret = btrfs_del_items(trans, root, path, pending_del_slot,
2805 btrfs_free_path(path);
2806 inode->i_sb->s_dirt = 1;
2811 * taken from block_truncate_page, but does cow as it zeros out
2812 * any bytes left in the last page in the file.
2814 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
2816 struct inode *inode = mapping->host;
2817 struct btrfs_root *root = BTRFS_I(inode)->root;
2818 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2819 struct btrfs_ordered_extent *ordered;
2821 u32 blocksize = root->sectorsize;
2822 pgoff_t index = from >> PAGE_CACHE_SHIFT;
2823 unsigned offset = from & (PAGE_CACHE_SIZE-1);
2829 if ((offset & (blocksize - 1)) == 0)
2834 page = grab_cache_page(mapping, index);
2838 page_start = page_offset(page);
2839 page_end = page_start + PAGE_CACHE_SIZE - 1;
2841 if (!PageUptodate(page)) {
2842 ret = btrfs_readpage(NULL, page);
2844 if (page->mapping != mapping) {
2846 page_cache_release(page);
2849 if (!PageUptodate(page)) {
2854 wait_on_page_writeback(page);
2856 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2857 set_page_extent_mapped(page);
2859 ordered = btrfs_lookup_ordered_extent(inode, page_start);
2861 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2863 page_cache_release(page);
2864 btrfs_start_ordered_extent(inode, ordered, 1);
2865 btrfs_put_ordered_extent(ordered);
2869 btrfs_set_extent_delalloc(inode, page_start, page_end);
2871 if (offset != PAGE_CACHE_SIZE) {
2873 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
2874 flush_dcache_page(page);
2877 ClearPageChecked(page);
2878 set_page_dirty(page);
2879 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2883 page_cache_release(page);
2888 int btrfs_cont_expand(struct inode *inode, loff_t size)
2890 struct btrfs_trans_handle *trans;
2891 struct btrfs_root *root = BTRFS_I(inode)->root;
2892 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2893 struct extent_map *em;
2894 u64 mask = root->sectorsize - 1;
2895 u64 hole_start = (inode->i_size + mask) & ~mask;
2896 u64 block_end = (size + mask) & ~mask;
2902 if (size <= hole_start)
2905 err = btrfs_check_metadata_free_space(root);
2909 btrfs_truncate_page(inode->i_mapping, inode->i_size);
2912 struct btrfs_ordered_extent *ordered;
2913 btrfs_wait_ordered_range(inode, hole_start,
2914 block_end - hole_start);
2915 lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
2916 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
2919 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
2920 btrfs_put_ordered_extent(ordered);
2923 trans = btrfs_start_transaction(root, 1);
2924 btrfs_set_trans_block_group(trans, inode);
2926 cur_offset = hole_start;
2928 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
2929 block_end - cur_offset, 0);
2930 BUG_ON(IS_ERR(em) || !em);
2931 last_byte = min(extent_map_end(em), block_end);
2932 last_byte = (last_byte + mask) & ~mask;
2933 if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) {
2935 hole_size = last_byte - cur_offset;
2936 err = btrfs_drop_extents(trans, root, inode,
2938 cur_offset + hole_size,
2940 cur_offset, &hint_byte);
2943 err = btrfs_insert_file_extent(trans, root,
2944 inode->i_ino, cur_offset, 0,
2945 0, hole_size, 0, hole_size,
2947 btrfs_drop_extent_cache(inode, hole_start,
2950 free_extent_map(em);
2951 cur_offset = last_byte;
2952 if (err || cur_offset >= block_end)
2956 btrfs_end_transaction(trans, root);
2957 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
2961 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
2963 struct inode *inode = dentry->d_inode;
2966 err = inode_change_ok(inode, attr);
2970 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
2971 if (attr->ia_size > inode->i_size) {
2972 err = btrfs_cont_expand(inode, attr->ia_size);
2975 } else if (inode->i_size > 0 &&
2976 attr->ia_size == 0) {
2978 /* we're truncating a file that used to have good
2979 * data down to zero. Make sure it gets into
2980 * the ordered flush list so that any new writes
2981 * get down to disk quickly.
2983 BTRFS_I(inode)->ordered_data_close = 1;
2987 err = inode_setattr(inode, attr);
2989 if (!err && ((attr->ia_valid & ATTR_MODE)))
2990 err = btrfs_acl_chmod(inode);
2994 void btrfs_delete_inode(struct inode *inode)
2996 struct btrfs_trans_handle *trans;
2997 struct btrfs_root *root = BTRFS_I(inode)->root;
3001 truncate_inode_pages(&inode->i_data, 0);
3002 if (is_bad_inode(inode)) {
3003 btrfs_orphan_del(NULL, inode);
3006 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3008 btrfs_i_size_write(inode, 0);
3009 trans = btrfs_join_transaction(root, 1);
3011 btrfs_set_trans_block_group(trans, inode);
3012 ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size, 0);
3014 btrfs_orphan_del(NULL, inode);
3015 goto no_delete_lock;
3018 btrfs_orphan_del(trans, inode);
3020 nr = trans->blocks_used;
3023 btrfs_end_transaction(trans, root);
3024 btrfs_btree_balance_dirty(root, nr);
3028 nr = trans->blocks_used;
3029 btrfs_end_transaction(trans, root);
3030 btrfs_btree_balance_dirty(root, nr);
3036 * this returns the key found in the dir entry in the location pointer.
3037 * If no dir entries were found, location->objectid is 0.
3039 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3040 struct btrfs_key *location)
3042 const char *name = dentry->d_name.name;
3043 int namelen = dentry->d_name.len;
3044 struct btrfs_dir_item *di;
3045 struct btrfs_path *path;
3046 struct btrfs_root *root = BTRFS_I(dir)->root;
3049 path = btrfs_alloc_path();
3052 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
3057 if (!di || IS_ERR(di))
3060 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3062 btrfs_free_path(path);
3065 location->objectid = 0;
3070 * when we hit a tree root in a directory, the btrfs part of the inode
3071 * needs to be changed to reflect the root directory of the tree root. This
3072 * is kind of like crossing a mount point.
3074 static int fixup_tree_root_location(struct btrfs_root *root,
3075 struct btrfs_key *location,
3076 struct btrfs_root **sub_root,
3077 struct dentry *dentry)
3079 struct btrfs_root_item *ri;
3081 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
3083 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
3086 *sub_root = btrfs_read_fs_root(root->fs_info, location,
3087 dentry->d_name.name,
3088 dentry->d_name.len);
3089 if (IS_ERR(*sub_root))
3090 return PTR_ERR(*sub_root);
3092 ri = &(*sub_root)->root_item;
3093 location->objectid = btrfs_root_dirid(ri);
3094 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
3095 location->offset = 0;
3100 static void inode_tree_add(struct inode *inode)
3102 struct btrfs_root *root = BTRFS_I(inode)->root;
3103 struct btrfs_inode *entry;
3104 struct rb_node **p = &root->inode_tree.rb_node;
3105 struct rb_node *parent = NULL;
3107 spin_lock(&root->inode_lock);
3110 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3112 if (inode->i_ino < entry->vfs_inode.i_ino)
3114 else if (inode->i_ino > entry->vfs_inode.i_ino)
3115 p = &(*p)->rb_right;
3117 WARN_ON(!(entry->vfs_inode.i_state &
3118 (I_WILL_FREE | I_FREEING | I_CLEAR)));
3122 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3123 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3124 spin_unlock(&root->inode_lock);
3127 static void inode_tree_del(struct inode *inode)
3129 struct btrfs_root *root = BTRFS_I(inode)->root;
3131 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3132 spin_lock(&root->inode_lock);
3133 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3134 spin_unlock(&root->inode_lock);
3135 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3139 static noinline void init_btrfs_i(struct inode *inode)
3141 struct btrfs_inode *bi = BTRFS_I(inode);
3143 bi->i_acl = BTRFS_ACL_NOT_CACHED;
3144 bi->i_default_acl = BTRFS_ACL_NOT_CACHED;
3149 bi->logged_trans = 0;
3150 bi->delalloc_bytes = 0;
3151 bi->reserved_bytes = 0;
3152 bi->disk_i_size = 0;
3154 bi->index_cnt = (u64)-1;
3155 bi->last_unlink_trans = 0;
3156 bi->ordered_data_close = 0;
3157 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
3158 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
3159 inode->i_mapping, GFP_NOFS);
3160 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
3161 inode->i_mapping, GFP_NOFS);
3162 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
3163 INIT_LIST_HEAD(&BTRFS_I(inode)->ordered_operations);
3164 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3165 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
3166 mutex_init(&BTRFS_I(inode)->extent_mutex);
3167 mutex_init(&BTRFS_I(inode)->log_mutex);
3170 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3172 struct btrfs_iget_args *args = p;
3173 inode->i_ino = args->ino;
3174 init_btrfs_i(inode);
3175 BTRFS_I(inode)->root = args->root;
3176 btrfs_set_inode_space_info(args->root, inode);
3180 static int btrfs_find_actor(struct inode *inode, void *opaque)
3182 struct btrfs_iget_args *args = opaque;
3183 return args->ino == inode->i_ino &&
3184 args->root == BTRFS_I(inode)->root;
3187 static struct inode *btrfs_iget_locked(struct super_block *s,
3189 struct btrfs_root *root)
3191 struct inode *inode;
3192 struct btrfs_iget_args args;
3193 args.ino = objectid;
3196 inode = iget5_locked(s, objectid, btrfs_find_actor,
3197 btrfs_init_locked_inode,
3202 /* Get an inode object given its location and corresponding root.
3203 * Returns in *is_new if the inode was read from disk
3205 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3206 struct btrfs_root *root)
3208 struct inode *inode;
3210 inode = btrfs_iget_locked(s, location->objectid, root);
3212 return ERR_PTR(-ENOMEM);
3214 if (inode->i_state & I_NEW) {
3215 BTRFS_I(inode)->root = root;
3216 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3217 btrfs_read_locked_inode(inode);
3219 inode_tree_add(inode);
3220 unlock_new_inode(inode);
3226 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3228 struct inode *inode;
3229 struct btrfs_inode *bi = BTRFS_I(dir);
3230 struct btrfs_root *root = bi->root;
3231 struct btrfs_root *sub_root = root;
3232 struct btrfs_key location;
3235 if (dentry->d_name.len > BTRFS_NAME_LEN)
3236 return ERR_PTR(-ENAMETOOLONG);
3238 ret = btrfs_inode_by_name(dir, dentry, &location);
3241 return ERR_PTR(ret);
3244 if (location.objectid) {
3245 ret = fixup_tree_root_location(root, &location, &sub_root,
3248 return ERR_PTR(ret);
3250 return ERR_PTR(-ENOENT);
3251 inode = btrfs_iget(dir->i_sb, &location, sub_root);
3253 return ERR_CAST(inode);
3258 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
3259 struct nameidata *nd)
3261 struct inode *inode;
3263 if (dentry->d_name.len > BTRFS_NAME_LEN)
3264 return ERR_PTR(-ENAMETOOLONG);
3266 inode = btrfs_lookup_dentry(dir, dentry);
3268 return ERR_CAST(inode);
3270 return d_splice_alias(inode, dentry);
3273 static unsigned char btrfs_filetype_table[] = {
3274 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
3277 static int btrfs_real_readdir(struct file *filp, void *dirent,
3280 struct inode *inode = filp->f_dentry->d_inode;
3281 struct btrfs_root *root = BTRFS_I(inode)->root;
3282 struct btrfs_item *item;
3283 struct btrfs_dir_item *di;
3284 struct btrfs_key key;
3285 struct btrfs_key found_key;
3286 struct btrfs_path *path;
3289 struct extent_buffer *leaf;
3292 unsigned char d_type;
3297 int key_type = BTRFS_DIR_INDEX_KEY;
3302 /* FIXME, use a real flag for deciding about the key type */
3303 if (root->fs_info->tree_root == root)
3304 key_type = BTRFS_DIR_ITEM_KEY;
3306 /* special case for "." */
3307 if (filp->f_pos == 0) {
3308 over = filldir(dirent, ".", 1,
3315 /* special case for .., just use the back ref */
3316 if (filp->f_pos == 1) {
3317 u64 pino = parent_ino(filp->f_path.dentry);
3318 over = filldir(dirent, "..", 2,
3324 path = btrfs_alloc_path();
3327 btrfs_set_key_type(&key, key_type);
3328 key.offset = filp->f_pos;
3329 key.objectid = inode->i_ino;
3331 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3337 leaf = path->nodes[0];
3338 nritems = btrfs_header_nritems(leaf);
3339 slot = path->slots[0];
3340 if (advance || slot >= nritems) {
3341 if (slot >= nritems - 1) {
3342 ret = btrfs_next_leaf(root, path);
3345 leaf = path->nodes[0];
3346 nritems = btrfs_header_nritems(leaf);
3347 slot = path->slots[0];
3355 item = btrfs_item_nr(leaf, slot);
3356 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3358 if (found_key.objectid != key.objectid)
3360 if (btrfs_key_type(&found_key) != key_type)
3362 if (found_key.offset < filp->f_pos)
3365 filp->f_pos = found_key.offset;
3367 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
3369 di_total = btrfs_item_size(leaf, item);
3371 while (di_cur < di_total) {
3372 struct btrfs_key location;
3374 name_len = btrfs_dir_name_len(leaf, di);
3375 if (name_len <= sizeof(tmp_name)) {
3376 name_ptr = tmp_name;
3378 name_ptr = kmalloc(name_len, GFP_NOFS);
3384 read_extent_buffer(leaf, name_ptr,
3385 (unsigned long)(di + 1), name_len);
3387 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
3388 btrfs_dir_item_key_to_cpu(leaf, di, &location);
3390 /* is this a reference to our own snapshot? If so
3393 if (location.type == BTRFS_ROOT_ITEM_KEY &&
3394 location.objectid == root->root_key.objectid) {
3398 over = filldir(dirent, name_ptr, name_len,
3399 found_key.offset, location.objectid,
3403 if (name_ptr != tmp_name)
3408 di_len = btrfs_dir_name_len(leaf, di) +
3409 btrfs_dir_data_len(leaf, di) + sizeof(*di);
3411 di = (struct btrfs_dir_item *)((char *)di + di_len);
3415 /* Reached end of directory/root. Bump pos past the last item. */
3416 if (key_type == BTRFS_DIR_INDEX_KEY)
3417 filp->f_pos = INT_LIMIT(off_t);
3423 btrfs_free_path(path);
3427 int btrfs_write_inode(struct inode *inode, int wait)
3429 struct btrfs_root *root = BTRFS_I(inode)->root;
3430 struct btrfs_trans_handle *trans;
3433 if (root->fs_info->btree_inode == inode)
3437 trans = btrfs_join_transaction(root, 1);
3438 btrfs_set_trans_block_group(trans, inode);
3439 ret = btrfs_commit_transaction(trans, root);
3445 * This is somewhat expensive, updating the tree every time the
3446 * inode changes. But, it is most likely to find the inode in cache.
3447 * FIXME, needs more benchmarking...there are no reasons other than performance
3448 * to keep or drop this code.
3450 void btrfs_dirty_inode(struct inode *inode)
3452 struct btrfs_root *root = BTRFS_I(inode)->root;
3453 struct btrfs_trans_handle *trans;
3455 trans = btrfs_join_transaction(root, 1);
3456 btrfs_set_trans_block_group(trans, inode);
3457 btrfs_update_inode(trans, root, inode);
3458 btrfs_end_transaction(trans, root);
3462 * find the highest existing sequence number in a directory
3463 * and then set the in-memory index_cnt variable to reflect
3464 * free sequence numbers
3466 static int btrfs_set_inode_index_count(struct inode *inode)
3468 struct btrfs_root *root = BTRFS_I(inode)->root;
3469 struct btrfs_key key, found_key;
3470 struct btrfs_path *path;
3471 struct extent_buffer *leaf;
3474 key.objectid = inode->i_ino;
3475 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
3476 key.offset = (u64)-1;
3478 path = btrfs_alloc_path();
3482 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3485 /* FIXME: we should be able to handle this */
3491 * MAGIC NUMBER EXPLANATION:
3492 * since we search a directory based on f_pos we have to start at 2
3493 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
3494 * else has to start at 2
3496 if (path->slots[0] == 0) {
3497 BTRFS_I(inode)->index_cnt = 2;
3503 leaf = path->nodes[0];
3504 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3506 if (found_key.objectid != inode->i_ino ||
3507 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
3508 BTRFS_I(inode)->index_cnt = 2;
3512 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
3514 btrfs_free_path(path);
3519 * helper to find a free sequence number in a given directory. This current
3520 * code is very simple, later versions will do smarter things in the btree
3522 int btrfs_set_inode_index(struct inode *dir, u64 *index)
3526 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
3527 ret = btrfs_set_inode_index_count(dir);
3532 *index = BTRFS_I(dir)->index_cnt;
3533 BTRFS_I(dir)->index_cnt++;
3538 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
3539 struct btrfs_root *root,
3541 const char *name, int name_len,
3542 u64 ref_objectid, u64 objectid,
3543 u64 alloc_hint, int mode, u64 *index)
3545 struct inode *inode;
3546 struct btrfs_inode_item *inode_item;
3547 struct btrfs_key *location;
3548 struct btrfs_path *path;
3549 struct btrfs_inode_ref *ref;
3550 struct btrfs_key key[2];
3556 path = btrfs_alloc_path();
3559 inode = new_inode(root->fs_info->sb);
3561 return ERR_PTR(-ENOMEM);
3564 ret = btrfs_set_inode_index(dir, index);
3567 return ERR_PTR(ret);
3571 * index_cnt is ignored for everything but a dir,
3572 * btrfs_get_inode_index_count has an explanation for the magic
3575 init_btrfs_i(inode);
3576 BTRFS_I(inode)->index_cnt = 2;
3577 BTRFS_I(inode)->root = root;
3578 BTRFS_I(inode)->generation = trans->transid;
3579 btrfs_set_inode_space_info(root, inode);
3585 BTRFS_I(inode)->block_group =
3586 btrfs_find_block_group(root, 0, alloc_hint, owner);
3587 if ((mode & S_IFREG)) {
3588 if (btrfs_test_opt(root, NODATASUM))
3589 btrfs_set_flag(inode, NODATASUM);
3590 if (btrfs_test_opt(root, NODATACOW))
3591 btrfs_set_flag(inode, NODATACOW);
3594 key[0].objectid = objectid;
3595 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
3598 key[1].objectid = objectid;
3599 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
3600 key[1].offset = ref_objectid;
3602 sizes[0] = sizeof(struct btrfs_inode_item);
3603 sizes[1] = name_len + sizeof(*ref);
3605 path->leave_spinning = 1;
3606 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
3610 if (objectid > root->highest_inode)
3611 root->highest_inode = objectid;
3613 inode->i_uid = current_fsuid();
3615 if (dir && (dir->i_mode & S_ISGID)) {
3616 inode->i_gid = dir->i_gid;
3620 inode->i_gid = current_fsgid();
3622 inode->i_mode = mode;
3623 inode->i_ino = objectid;
3624 inode_set_bytes(inode, 0);
3625 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3626 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
3627 struct btrfs_inode_item);
3628 fill_inode_item(trans, path->nodes[0], inode_item, inode);
3630 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
3631 struct btrfs_inode_ref);
3632 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
3633 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
3634 ptr = (unsigned long)(ref + 1);
3635 write_extent_buffer(path->nodes[0], name, ptr, name_len);
3637 btrfs_mark_buffer_dirty(path->nodes[0]);
3638 btrfs_free_path(path);
3640 location = &BTRFS_I(inode)->location;
3641 location->objectid = objectid;
3642 location->offset = 0;
3643 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
3645 insert_inode_hash(inode);
3646 inode_tree_add(inode);
3650 BTRFS_I(dir)->index_cnt--;
3651 btrfs_free_path(path);
3653 return ERR_PTR(ret);
3656 static inline u8 btrfs_inode_type(struct inode *inode)
3658 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
3662 * utility function to add 'inode' into 'parent_inode' with
3663 * a give name and a given sequence number.
3664 * if 'add_backref' is true, also insert a backref from the
3665 * inode to the parent directory.
3667 int btrfs_add_link(struct btrfs_trans_handle *trans,
3668 struct inode *parent_inode, struct inode *inode,
3669 const char *name, int name_len, int add_backref, u64 index)
3672 struct btrfs_key key;
3673 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
3675 key.objectid = inode->i_ino;
3676 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
3679 ret = btrfs_insert_dir_item(trans, root, name, name_len,
3680 parent_inode->i_ino,
3681 &key, btrfs_inode_type(inode),
3685 ret = btrfs_insert_inode_ref(trans, root,
3688 parent_inode->i_ino,
3691 btrfs_i_size_write(parent_inode, parent_inode->i_size +
3693 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
3694 ret = btrfs_update_inode(trans, root, parent_inode);
3699 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
3700 struct dentry *dentry, struct inode *inode,
3701 int backref, u64 index)
3703 int err = btrfs_add_link(trans, dentry->d_parent->d_inode,
3704 inode, dentry->d_name.name,
3705 dentry->d_name.len, backref, index);
3707 d_instantiate(dentry, inode);
3715 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
3716 int mode, dev_t rdev)
3718 struct btrfs_trans_handle *trans;
3719 struct btrfs_root *root = BTRFS_I(dir)->root;
3720 struct inode *inode = NULL;
3724 unsigned long nr = 0;
3727 if (!new_valid_dev(rdev))
3730 err = btrfs_check_metadata_free_space(root);
3734 trans = btrfs_start_transaction(root, 1);
3735 btrfs_set_trans_block_group(trans, dir);
3737 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3743 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3745 dentry->d_parent->d_inode->i_ino, objectid,
3746 BTRFS_I(dir)->block_group, mode, &index);
3747 err = PTR_ERR(inode);
3751 err = btrfs_init_inode_security(inode, dir);
3757 btrfs_set_trans_block_group(trans, inode);
3758 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
3762 inode->i_op = &btrfs_special_inode_operations;
3763 init_special_inode(inode, inode->i_mode, rdev);
3764 btrfs_update_inode(trans, root, inode);
3766 dir->i_sb->s_dirt = 1;
3767 btrfs_update_inode_block_group(trans, inode);
3768 btrfs_update_inode_block_group(trans, dir);
3770 nr = trans->blocks_used;
3771 btrfs_end_transaction_throttle(trans, root);
3774 inode_dec_link_count(inode);
3777 btrfs_btree_balance_dirty(root, nr);
3781 static int btrfs_create(struct inode *dir, struct dentry *dentry,
3782 int mode, struct nameidata *nd)
3784 struct btrfs_trans_handle *trans;
3785 struct btrfs_root *root = BTRFS_I(dir)->root;
3786 struct inode *inode = NULL;
3789 unsigned long nr = 0;
3793 err = btrfs_check_metadata_free_space(root);
3796 trans = btrfs_start_transaction(root, 1);
3797 btrfs_set_trans_block_group(trans, dir);
3799 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3805 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3807 dentry->d_parent->d_inode->i_ino,
3808 objectid, BTRFS_I(dir)->block_group, mode,
3810 err = PTR_ERR(inode);
3814 err = btrfs_init_inode_security(inode, dir);
3820 btrfs_set_trans_block_group(trans, inode);
3821 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
3825 inode->i_mapping->a_ops = &btrfs_aops;
3826 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3827 inode->i_fop = &btrfs_file_operations;
3828 inode->i_op = &btrfs_file_inode_operations;
3829 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3831 dir->i_sb->s_dirt = 1;
3832 btrfs_update_inode_block_group(trans, inode);
3833 btrfs_update_inode_block_group(trans, dir);
3835 nr = trans->blocks_used;
3836 btrfs_end_transaction_throttle(trans, root);
3839 inode_dec_link_count(inode);
3842 btrfs_btree_balance_dirty(root, nr);
3846 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
3847 struct dentry *dentry)
3849 struct btrfs_trans_handle *trans;
3850 struct btrfs_root *root = BTRFS_I(dir)->root;
3851 struct inode *inode = old_dentry->d_inode;
3853 unsigned long nr = 0;
3857 if (inode->i_nlink == 0)
3860 btrfs_inc_nlink(inode);
3861 err = btrfs_check_metadata_free_space(root);
3864 err = btrfs_set_inode_index(dir, &index);
3868 trans = btrfs_start_transaction(root, 1);
3870 btrfs_set_trans_block_group(trans, dir);
3871 atomic_inc(&inode->i_count);
3873 err = btrfs_add_nondir(trans, dentry, inode, 1, index);
3878 dir->i_sb->s_dirt = 1;
3879 btrfs_update_inode_block_group(trans, dir);
3880 err = btrfs_update_inode(trans, root, inode);
3885 nr = trans->blocks_used;
3887 btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
3888 btrfs_end_transaction_throttle(trans, root);
3891 inode_dec_link_count(inode);
3894 btrfs_btree_balance_dirty(root, nr);
3898 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
3900 struct inode *inode = NULL;
3901 struct btrfs_trans_handle *trans;
3902 struct btrfs_root *root = BTRFS_I(dir)->root;
3904 int drop_on_err = 0;
3907 unsigned long nr = 1;
3909 err = btrfs_check_metadata_free_space(root);
3913 trans = btrfs_start_transaction(root, 1);
3914 btrfs_set_trans_block_group(trans, dir);
3916 if (IS_ERR(trans)) {
3917 err = PTR_ERR(trans);
3921 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3927 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3929 dentry->d_parent->d_inode->i_ino, objectid,
3930 BTRFS_I(dir)->block_group, S_IFDIR | mode,
3932 if (IS_ERR(inode)) {
3933 err = PTR_ERR(inode);
3939 err = btrfs_init_inode_security(inode, dir);
3943 inode->i_op = &btrfs_dir_inode_operations;
3944 inode->i_fop = &btrfs_dir_file_operations;
3945 btrfs_set_trans_block_group(trans, inode);
3947 btrfs_i_size_write(inode, 0);
3948 err = btrfs_update_inode(trans, root, inode);
3952 err = btrfs_add_link(trans, dentry->d_parent->d_inode,
3953 inode, dentry->d_name.name,
3954 dentry->d_name.len, 0, index);
3958 d_instantiate(dentry, inode);
3960 dir->i_sb->s_dirt = 1;
3961 btrfs_update_inode_block_group(trans, inode);
3962 btrfs_update_inode_block_group(trans, dir);
3965 nr = trans->blocks_used;
3966 btrfs_end_transaction_throttle(trans, root);
3971 btrfs_btree_balance_dirty(root, nr);
3975 /* helper for btfs_get_extent. Given an existing extent in the tree,
3976 * and an extent that you want to insert, deal with overlap and insert
3977 * the new extent into the tree.
3979 static int merge_extent_mapping(struct extent_map_tree *em_tree,
3980 struct extent_map *existing,
3981 struct extent_map *em,
3982 u64 map_start, u64 map_len)
3986 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
3987 start_diff = map_start - em->start;
3988 em->start = map_start;
3990 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
3991 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
3992 em->block_start += start_diff;
3993 em->block_len -= start_diff;
3995 return add_extent_mapping(em_tree, em);
3998 static noinline int uncompress_inline(struct btrfs_path *path,
3999 struct inode *inode, struct page *page,
4000 size_t pg_offset, u64 extent_offset,
4001 struct btrfs_file_extent_item *item)
4004 struct extent_buffer *leaf = path->nodes[0];
4007 unsigned long inline_size;
4010 WARN_ON(pg_offset != 0);
4011 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4012 inline_size = btrfs_file_extent_inline_item_len(leaf,
4013 btrfs_item_nr(leaf, path->slots[0]));
4014 tmp = kmalloc(inline_size, GFP_NOFS);
4015 ptr = btrfs_file_extent_inline_start(item);
4017 read_extent_buffer(leaf, tmp, ptr, inline_size);
4019 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4020 ret = btrfs_zlib_decompress(tmp, page, extent_offset,
4021 inline_size, max_size);
4023 char *kaddr = kmap_atomic(page, KM_USER0);
4024 unsigned long copy_size = min_t(u64,
4025 PAGE_CACHE_SIZE - pg_offset,
4026 max_size - extent_offset);
4027 memset(kaddr + pg_offset, 0, copy_size);
4028 kunmap_atomic(kaddr, KM_USER0);
4035 * a bit scary, this does extent mapping from logical file offset to the disk.
4036 * the ugly parts come from merging extents from the disk with the in-ram
4037 * representation. This gets more complex because of the data=ordered code,
4038 * where the in-ram extents might be locked pending data=ordered completion.
4040 * This also copies inline extents directly into the page.
4043 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4044 size_t pg_offset, u64 start, u64 len,
4050 u64 extent_start = 0;
4052 u64 objectid = inode->i_ino;
4054 struct btrfs_path *path = NULL;
4055 struct btrfs_root *root = BTRFS_I(inode)->root;
4056 struct btrfs_file_extent_item *item;
4057 struct extent_buffer *leaf;
4058 struct btrfs_key found_key;
4059 struct extent_map *em = NULL;
4060 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4061 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4062 struct btrfs_trans_handle *trans = NULL;
4066 spin_lock(&em_tree->lock);
4067 em = lookup_extent_mapping(em_tree, start, len);
4069 em->bdev = root->fs_info->fs_devices->latest_bdev;
4070 spin_unlock(&em_tree->lock);
4073 if (em->start > start || em->start + em->len <= start)
4074 free_extent_map(em);
4075 else if (em->block_start == EXTENT_MAP_INLINE && page)
4076 free_extent_map(em);
4080 em = alloc_extent_map(GFP_NOFS);
4085 em->bdev = root->fs_info->fs_devices->latest_bdev;
4086 em->start = EXTENT_MAP_HOLE;
4087 em->orig_start = EXTENT_MAP_HOLE;
4089 em->block_len = (u64)-1;
4092 path = btrfs_alloc_path();
4096 ret = btrfs_lookup_file_extent(trans, root, path,
4097 objectid, start, trans != NULL);
4104 if (path->slots[0] == 0)
4109 leaf = path->nodes[0];
4110 item = btrfs_item_ptr(leaf, path->slots[0],
4111 struct btrfs_file_extent_item);
4112 /* are we inside the extent that was found? */
4113 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4114 found_type = btrfs_key_type(&found_key);
4115 if (found_key.objectid != objectid ||
4116 found_type != BTRFS_EXTENT_DATA_KEY) {
4120 found_type = btrfs_file_extent_type(leaf, item);
4121 extent_start = found_key.offset;
4122 compressed = btrfs_file_extent_compression(leaf, item);
4123 if (found_type == BTRFS_FILE_EXTENT_REG ||
4124 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
4125 extent_end = extent_start +
4126 btrfs_file_extent_num_bytes(leaf, item);
4127 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
4129 size = btrfs_file_extent_inline_len(leaf, item);
4130 extent_end = (extent_start + size + root->sectorsize - 1) &
4131 ~((u64)root->sectorsize - 1);
4134 if (start >= extent_end) {
4136 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
4137 ret = btrfs_next_leaf(root, path);
4144 leaf = path->nodes[0];
4146 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4147 if (found_key.objectid != objectid ||
4148 found_key.type != BTRFS_EXTENT_DATA_KEY)
4150 if (start + len <= found_key.offset)
4153 em->len = found_key.offset - start;
4157 if (found_type == BTRFS_FILE_EXTENT_REG ||
4158 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
4159 em->start = extent_start;
4160 em->len = extent_end - extent_start;
4161 em->orig_start = extent_start -
4162 btrfs_file_extent_offset(leaf, item);
4163 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
4165 em->block_start = EXTENT_MAP_HOLE;
4169 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
4170 em->block_start = bytenr;
4171 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
4174 bytenr += btrfs_file_extent_offset(leaf, item);
4175 em->block_start = bytenr;
4176 em->block_len = em->len;
4177 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
4178 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
4181 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
4185 size_t extent_offset;
4188 em->block_start = EXTENT_MAP_INLINE;
4189 if (!page || create) {
4190 em->start = extent_start;
4191 em->len = extent_end - extent_start;
4195 size = btrfs_file_extent_inline_len(leaf, item);
4196 extent_offset = page_offset(page) + pg_offset - extent_start;
4197 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
4198 size - extent_offset);
4199 em->start = extent_start + extent_offset;
4200 em->len = (copy_size + root->sectorsize - 1) &
4201 ~((u64)root->sectorsize - 1);
4202 em->orig_start = EXTENT_MAP_INLINE;
4204 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
4205 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
4206 if (create == 0 && !PageUptodate(page)) {
4207 if (btrfs_file_extent_compression(leaf, item) ==
4208 BTRFS_COMPRESS_ZLIB) {
4209 ret = uncompress_inline(path, inode, page,
4211 extent_offset, item);
4215 read_extent_buffer(leaf, map + pg_offset, ptr,
4219 flush_dcache_page(page);
4220 } else if (create && PageUptodate(page)) {
4223 free_extent_map(em);
4225 btrfs_release_path(root, path);
4226 trans = btrfs_join_transaction(root, 1);
4230 write_extent_buffer(leaf, map + pg_offset, ptr,
4233 btrfs_mark_buffer_dirty(leaf);
4235 set_extent_uptodate(io_tree, em->start,
4236 extent_map_end(em) - 1, GFP_NOFS);
4239 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
4246 em->block_start = EXTENT_MAP_HOLE;
4247 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
4249 btrfs_release_path(root, path);
4250 if (em->start > start || extent_map_end(em) <= start) {
4251 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
4252 "[%llu %llu]\n", (unsigned long long)em->start,
4253 (unsigned long long)em->len,
4254 (unsigned long long)start,
4255 (unsigned long long)len);
4261 spin_lock(&em_tree->lock);
4262 ret = add_extent_mapping(em_tree, em);
4263 /* it is possible that someone inserted the extent into the tree
4264 * while we had the lock dropped. It is also possible that
4265 * an overlapping map exists in the tree
4267 if (ret == -EEXIST) {
4268 struct extent_map *existing;
4272 existing = lookup_extent_mapping(em_tree, start, len);
4273 if (existing && (existing->start > start ||
4274 existing->start + existing->len <= start)) {
4275 free_extent_map(existing);
4279 existing = lookup_extent_mapping(em_tree, em->start,
4282 err = merge_extent_mapping(em_tree, existing,
4285 free_extent_map(existing);
4287 free_extent_map(em);
4292 free_extent_map(em);
4296 free_extent_map(em);
4301 spin_unlock(&em_tree->lock);
4304 btrfs_free_path(path);
4306 ret = btrfs_end_transaction(trans, root);
4311 free_extent_map(em);
4312 return ERR_PTR(err);
4317 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
4318 const struct iovec *iov, loff_t offset,
4319 unsigned long nr_segs)
4324 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4325 __u64 start, __u64 len)
4327 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent);
4330 int btrfs_readpage(struct file *file, struct page *page)
4332 struct extent_io_tree *tree;
4333 tree = &BTRFS_I(page->mapping->host)->io_tree;
4334 return extent_read_full_page(tree, page, btrfs_get_extent);
4337 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
4339 struct extent_io_tree *tree;
4342 if (current->flags & PF_MEMALLOC) {
4343 redirty_page_for_writepage(wbc, page);
4347 tree = &BTRFS_I(page->mapping->host)->io_tree;
4348 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
4351 int btrfs_writepages(struct address_space *mapping,
4352 struct writeback_control *wbc)
4354 struct extent_io_tree *tree;
4356 tree = &BTRFS_I(mapping->host)->io_tree;
4357 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
4361 btrfs_readpages(struct file *file, struct address_space *mapping,
4362 struct list_head *pages, unsigned nr_pages)
4364 struct extent_io_tree *tree;
4365 tree = &BTRFS_I(mapping->host)->io_tree;
4366 return extent_readpages(tree, mapping, pages, nr_pages,
4369 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
4371 struct extent_io_tree *tree;
4372 struct extent_map_tree *map;
4375 tree = &BTRFS_I(page->mapping->host)->io_tree;
4376 map = &BTRFS_I(page->mapping->host)->extent_tree;
4377 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
4379 ClearPagePrivate(page);
4380 set_page_private(page, 0);
4381 page_cache_release(page);
4386 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
4388 if (PageWriteback(page) || PageDirty(page))
4390 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
4393 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
4395 struct extent_io_tree *tree;
4396 struct btrfs_ordered_extent *ordered;
4397 u64 page_start = page_offset(page);
4398 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
4400 wait_on_page_writeback(page);
4401 tree = &BTRFS_I(page->mapping->host)->io_tree;
4403 btrfs_releasepage(page, GFP_NOFS);
4407 lock_extent(tree, page_start, page_end, GFP_NOFS);
4408 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
4412 * IO on this page will never be started, so we need
4413 * to account for any ordered extents now
4415 clear_extent_bit(tree, page_start, page_end,
4416 EXTENT_DIRTY | EXTENT_DELALLOC |
4417 EXTENT_LOCKED, 1, 0, GFP_NOFS);
4418 btrfs_finish_ordered_io(page->mapping->host,
4419 page_start, page_end);
4420 btrfs_put_ordered_extent(ordered);
4421 lock_extent(tree, page_start, page_end, GFP_NOFS);
4423 clear_extent_bit(tree, page_start, page_end,
4424 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
4427 __btrfs_releasepage(page, GFP_NOFS);
4429 ClearPageChecked(page);
4430 if (PagePrivate(page)) {
4431 ClearPagePrivate(page);
4432 set_page_private(page, 0);
4433 page_cache_release(page);
4438 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
4439 * called from a page fault handler when a page is first dirtied. Hence we must
4440 * be careful to check for EOF conditions here. We set the page up correctly
4441 * for a written page which means we get ENOSPC checking when writing into
4442 * holes and correct delalloc and unwritten extent mapping on filesystems that
4443 * support these features.
4445 * We are not allowed to take the i_mutex here so we have to play games to
4446 * protect against truncate races as the page could now be beyond EOF. Because
4447 * vmtruncate() writes the inode size before removing pages, once we have the
4448 * page lock we can determine safely if the page is beyond EOF. If it is not
4449 * beyond EOF, then the page is guaranteed safe against truncation until we
4452 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
4454 struct page *page = vmf->page;
4455 struct inode *inode = fdentry(vma->vm_file)->d_inode;
4456 struct btrfs_root *root = BTRFS_I(inode)->root;
4457 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4458 struct btrfs_ordered_extent *ordered;
4460 unsigned long zero_start;
4466 ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE);
4470 else /* -ENOSPC, -EIO, etc */
4471 ret = VM_FAULT_SIGBUS;
4475 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
4478 size = i_size_read(inode);
4479 page_start = page_offset(page);
4480 page_end = page_start + PAGE_CACHE_SIZE - 1;
4482 if ((page->mapping != inode->i_mapping) ||
4483 (page_start >= size)) {
4484 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
4485 /* page got truncated out from underneath us */
4488 wait_on_page_writeback(page);
4490 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
4491 set_page_extent_mapped(page);
4494 * we can't set the delalloc bits if there are pending ordered
4495 * extents. Drop our locks and wait for them to finish
4497 ordered = btrfs_lookup_ordered_extent(inode, page_start);
4499 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
4501 btrfs_start_ordered_extent(inode, ordered, 1);
4502 btrfs_put_ordered_extent(ordered);
4506 btrfs_set_extent_delalloc(inode, page_start, page_end);
4509 /* page is wholly or partially inside EOF */
4510 if (page_start + PAGE_CACHE_SIZE > size)
4511 zero_start = size & ~PAGE_CACHE_MASK;
4513 zero_start = PAGE_CACHE_SIZE;
4515 if (zero_start != PAGE_CACHE_SIZE) {
4517 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
4518 flush_dcache_page(page);
4521 ClearPageChecked(page);
4522 set_page_dirty(page);
4524 BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
4525 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
4533 static void btrfs_truncate(struct inode *inode)
4535 struct btrfs_root *root = BTRFS_I(inode)->root;
4537 struct btrfs_trans_handle *trans;
4539 u64 mask = root->sectorsize - 1;
4541 if (!S_ISREG(inode->i_mode))
4543 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
4546 btrfs_truncate_page(inode->i_mapping, inode->i_size);
4547 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
4549 trans = btrfs_start_transaction(root, 1);
4552 * setattr is responsible for setting the ordered_data_close flag,
4553 * but that is only tested during the last file release. That
4554 * could happen well after the next commit, leaving a great big
4555 * window where new writes may get lost if someone chooses to write
4556 * to this file after truncating to zero
4558 * The inode doesn't have any dirty data here, and so if we commit
4559 * this is a noop. If someone immediately starts writing to the inode
4560 * it is very likely we'll catch some of their writes in this
4561 * transaction, and the commit will find this file on the ordered
4562 * data list with good things to send down.
4564 * This is a best effort solution, there is still a window where
4565 * using truncate to replace the contents of the file will
4566 * end up with a zero length file after a crash.
4568 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
4569 btrfs_add_ordered_operation(trans, root, inode);
4571 btrfs_set_trans_block_group(trans, inode);
4572 btrfs_i_size_write(inode, inode->i_size);
4574 ret = btrfs_orphan_add(trans, inode);
4577 /* FIXME, add redo link to tree so we don't leak on crash */
4578 ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size,
4579 BTRFS_EXTENT_DATA_KEY);
4580 btrfs_update_inode(trans, root, inode);
4582 ret = btrfs_orphan_del(trans, inode);
4586 nr = trans->blocks_used;
4587 ret = btrfs_end_transaction_throttle(trans, root);
4589 btrfs_btree_balance_dirty(root, nr);
4593 * create a new subvolume directory/inode (helper for the ioctl).
4595 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
4596 struct btrfs_root *new_root, struct dentry *dentry,
4597 u64 new_dirid, u64 alloc_hint)
4599 struct inode *inode;
4603 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
4604 new_dirid, alloc_hint, S_IFDIR | 0700, &index);
4606 return PTR_ERR(inode);
4607 inode->i_op = &btrfs_dir_inode_operations;
4608 inode->i_fop = &btrfs_dir_file_operations;
4611 btrfs_i_size_write(inode, 0);
4613 error = btrfs_update_inode(trans, new_root, inode);
4617 d_instantiate(dentry, inode);
4621 /* helper function for file defrag and space balancing. This
4622 * forces readahead on a given range of bytes in an inode
4624 unsigned long btrfs_force_ra(struct address_space *mapping,
4625 struct file_ra_state *ra, struct file *file,
4626 pgoff_t offset, pgoff_t last_index)
4628 pgoff_t req_size = last_index - offset + 1;
4630 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
4631 return offset + req_size;
4634 struct inode *btrfs_alloc_inode(struct super_block *sb)
4636 struct btrfs_inode *ei;
4638 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
4642 ei->logged_trans = 0;
4643 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
4644 ei->i_acl = BTRFS_ACL_NOT_CACHED;
4645 ei->i_default_acl = BTRFS_ACL_NOT_CACHED;
4646 INIT_LIST_HEAD(&ei->i_orphan);
4647 INIT_LIST_HEAD(&ei->ordered_operations);
4648 return &ei->vfs_inode;
4651 void btrfs_destroy_inode(struct inode *inode)
4653 struct btrfs_ordered_extent *ordered;
4654 struct btrfs_root *root = BTRFS_I(inode)->root;
4656 WARN_ON(!list_empty(&inode->i_dentry));
4657 WARN_ON(inode->i_data.nrpages);
4659 if (BTRFS_I(inode)->i_acl &&
4660 BTRFS_I(inode)->i_acl != BTRFS_ACL_NOT_CACHED)
4661 posix_acl_release(BTRFS_I(inode)->i_acl);
4662 if (BTRFS_I(inode)->i_default_acl &&
4663 BTRFS_I(inode)->i_default_acl != BTRFS_ACL_NOT_CACHED)
4664 posix_acl_release(BTRFS_I(inode)->i_default_acl);
4667 * Make sure we're properly removed from the ordered operation
4671 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
4672 spin_lock(&root->fs_info->ordered_extent_lock);
4673 list_del_init(&BTRFS_I(inode)->ordered_operations);
4674 spin_unlock(&root->fs_info->ordered_extent_lock);
4677 spin_lock(&root->list_lock);
4678 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
4679 printk(KERN_ERR "BTRFS: inode %lu: inode still on the orphan"
4680 " list\n", inode->i_ino);
4683 spin_unlock(&root->list_lock);
4686 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
4690 printk(KERN_ERR "btrfs found ordered "
4691 "extent %llu %llu on inode cleanup\n",
4692 (unsigned long long)ordered->file_offset,
4693 (unsigned long long)ordered->len);
4694 btrfs_remove_ordered_extent(inode, ordered);
4695 btrfs_put_ordered_extent(ordered);
4696 btrfs_put_ordered_extent(ordered);
4699 inode_tree_del(inode);
4700 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
4701 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
4704 static void init_once(void *foo)
4706 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
4708 inode_init_once(&ei->vfs_inode);
4711 void btrfs_destroy_cachep(void)
4713 if (btrfs_inode_cachep)
4714 kmem_cache_destroy(btrfs_inode_cachep);
4715 if (btrfs_trans_handle_cachep)
4716 kmem_cache_destroy(btrfs_trans_handle_cachep);
4717 if (btrfs_transaction_cachep)
4718 kmem_cache_destroy(btrfs_transaction_cachep);
4719 if (btrfs_path_cachep)
4720 kmem_cache_destroy(btrfs_path_cachep);
4723 int btrfs_init_cachep(void)
4725 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
4726 sizeof(struct btrfs_inode), 0,
4727 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
4728 if (!btrfs_inode_cachep)
4731 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
4732 sizeof(struct btrfs_trans_handle), 0,
4733 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
4734 if (!btrfs_trans_handle_cachep)
4737 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
4738 sizeof(struct btrfs_transaction), 0,
4739 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
4740 if (!btrfs_transaction_cachep)
4743 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
4744 sizeof(struct btrfs_path), 0,
4745 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
4746 if (!btrfs_path_cachep)
4751 btrfs_destroy_cachep();
4755 static int btrfs_getattr(struct vfsmount *mnt,
4756 struct dentry *dentry, struct kstat *stat)
4758 struct inode *inode = dentry->d_inode;
4759 generic_fillattr(inode, stat);
4760 stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
4761 stat->blksize = PAGE_CACHE_SIZE;
4762 stat->blocks = (inode_get_bytes(inode) +
4763 BTRFS_I(inode)->delalloc_bytes) >> 9;
4767 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
4768 struct inode *new_dir, struct dentry *new_dentry)
4770 struct btrfs_trans_handle *trans;
4771 struct btrfs_root *root = BTRFS_I(old_dir)->root;
4772 struct inode *new_inode = new_dentry->d_inode;
4773 struct inode *old_inode = old_dentry->d_inode;
4774 struct timespec ctime = CURRENT_TIME;
4778 /* we're not allowed to rename between subvolumes */
4779 if (BTRFS_I(old_inode)->root->root_key.objectid !=
4780 BTRFS_I(new_dir)->root->root_key.objectid)
4783 if (S_ISDIR(old_inode->i_mode) && new_inode &&
4784 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
4788 /* to rename a snapshot or subvolume, we need to juggle the
4789 * backrefs. This isn't coded yet
4791 if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
4794 ret = btrfs_check_metadata_free_space(root);
4799 * we're using rename to replace one file with another.
4800 * and the replacement file is large. Start IO on it now so
4801 * we don't add too much work to the end of the transaction
4803 if (new_inode && old_inode && S_ISREG(old_inode->i_mode) &&
4804 new_inode->i_size &&
4805 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
4806 filemap_flush(old_inode->i_mapping);
4808 trans = btrfs_start_transaction(root, 1);
4811 * make sure the inode gets flushed if it is replacing
4814 if (new_inode && new_inode->i_size &&
4815 old_inode && S_ISREG(old_inode->i_mode)) {
4816 btrfs_add_ordered_operation(trans, root, old_inode);
4820 * this is an ugly little race, but the rename is required to make
4821 * sure that if we crash, the inode is either at the old name
4822 * or the new one. pinning the log transaction lets us make sure
4823 * we don't allow a log commit to come in after we unlink the
4824 * name but before we add the new name back in.
4826 btrfs_pin_log_trans(root);
4828 btrfs_set_trans_block_group(trans, new_dir);
4830 btrfs_inc_nlink(old_dentry->d_inode);
4831 old_dir->i_ctime = old_dir->i_mtime = ctime;
4832 new_dir->i_ctime = new_dir->i_mtime = ctime;
4833 old_inode->i_ctime = ctime;
4835 if (old_dentry->d_parent != new_dentry->d_parent)
4836 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
4838 ret = btrfs_unlink_inode(trans, root, old_dir, old_dentry->d_inode,
4839 old_dentry->d_name.name,
4840 old_dentry->d_name.len);
4845 new_inode->i_ctime = CURRENT_TIME;
4846 ret = btrfs_unlink_inode(trans, root, new_dir,
4847 new_dentry->d_inode,
4848 new_dentry->d_name.name,
4849 new_dentry->d_name.len);
4852 if (new_inode->i_nlink == 0) {
4853 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
4859 ret = btrfs_set_inode_index(new_dir, &index);
4863 ret = btrfs_add_link(trans, new_dentry->d_parent->d_inode,
4864 old_inode, new_dentry->d_name.name,
4865 new_dentry->d_name.len, 1, index);
4869 btrfs_log_new_name(trans, old_inode, old_dir,
4870 new_dentry->d_parent);
4873 /* this btrfs_end_log_trans just allows the current
4874 * log-sub transaction to complete
4876 btrfs_end_log_trans(root);
4877 btrfs_end_transaction_throttle(trans, root);
4883 * some fairly slow code that needs optimization. This walks the list
4884 * of all the inodes with pending delalloc and forces them to disk.
4886 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
4888 struct list_head *head = &root->fs_info->delalloc_inodes;
4889 struct btrfs_inode *binode;
4890 struct inode *inode;
4892 if (root->fs_info->sb->s_flags & MS_RDONLY)
4895 spin_lock(&root->fs_info->delalloc_lock);
4896 while (!list_empty(head)) {
4897 binode = list_entry(head->next, struct btrfs_inode,
4899 inode = igrab(&binode->vfs_inode);
4901 list_del_init(&binode->delalloc_inodes);
4902 spin_unlock(&root->fs_info->delalloc_lock);
4904 filemap_flush(inode->i_mapping);
4908 spin_lock(&root->fs_info->delalloc_lock);
4910 spin_unlock(&root->fs_info->delalloc_lock);
4912 /* the filemap_flush will queue IO into the worker threads, but
4913 * we have to make sure the IO is actually started and that
4914 * ordered extents get created before we return
4916 atomic_inc(&root->fs_info->async_submit_draining);
4917 while (atomic_read(&root->fs_info->nr_async_submits) ||
4918 atomic_read(&root->fs_info->async_delalloc_pages)) {
4919 wait_event(root->fs_info->async_submit_wait,
4920 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
4921 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
4923 atomic_dec(&root->fs_info->async_submit_draining);
4927 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
4928 const char *symname)
4930 struct btrfs_trans_handle *trans;
4931 struct btrfs_root *root = BTRFS_I(dir)->root;
4932 struct btrfs_path *path;
4933 struct btrfs_key key;
4934 struct inode *inode = NULL;
4942 struct btrfs_file_extent_item *ei;
4943 struct extent_buffer *leaf;
4944 unsigned long nr = 0;
4946 name_len = strlen(symname) + 1;
4947 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
4948 return -ENAMETOOLONG;
4950 err = btrfs_check_metadata_free_space(root);
4954 trans = btrfs_start_transaction(root, 1);
4955 btrfs_set_trans_block_group(trans, dir);
4957 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
4963 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4965 dentry->d_parent->d_inode->i_ino, objectid,
4966 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO,
4968 err = PTR_ERR(inode);
4972 err = btrfs_init_inode_security(inode, dir);
4978 btrfs_set_trans_block_group(trans, inode);
4979 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
4983 inode->i_mapping->a_ops = &btrfs_aops;
4984 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4985 inode->i_fop = &btrfs_file_operations;
4986 inode->i_op = &btrfs_file_inode_operations;
4987 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4989 dir->i_sb->s_dirt = 1;
4990 btrfs_update_inode_block_group(trans, inode);
4991 btrfs_update_inode_block_group(trans, dir);
4995 path = btrfs_alloc_path();
4997 key.objectid = inode->i_ino;
4999 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
5000 datasize = btrfs_file_extent_calc_inline_size(name_len);
5001 err = btrfs_insert_empty_item(trans, root, path, &key,
5007 leaf = path->nodes[0];
5008 ei = btrfs_item_ptr(leaf, path->slots[0],
5009 struct btrfs_file_extent_item);
5010 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
5011 btrfs_set_file_extent_type(leaf, ei,
5012 BTRFS_FILE_EXTENT_INLINE);
5013 btrfs_set_file_extent_encryption(leaf, ei, 0);
5014 btrfs_set_file_extent_compression(leaf, ei, 0);
5015 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
5016 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
5018 ptr = btrfs_file_extent_inline_start(ei);
5019 write_extent_buffer(leaf, symname, ptr, name_len);
5020 btrfs_mark_buffer_dirty(leaf);
5021 btrfs_free_path(path);
5023 inode->i_op = &btrfs_symlink_inode_operations;
5024 inode->i_mapping->a_ops = &btrfs_symlink_aops;
5025 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5026 inode_set_bytes(inode, name_len);
5027 btrfs_i_size_write(inode, name_len - 1);
5028 err = btrfs_update_inode(trans, root, inode);
5033 nr = trans->blocks_used;
5034 btrfs_end_transaction_throttle(trans, root);
5037 inode_dec_link_count(inode);
5040 btrfs_btree_balance_dirty(root, nr);
5044 static int prealloc_file_range(struct btrfs_trans_handle *trans,
5045 struct inode *inode, u64 start, u64 end,
5046 u64 locked_end, u64 alloc_hint, int mode)
5048 struct btrfs_root *root = BTRFS_I(inode)->root;
5049 struct btrfs_key ins;
5051 u64 cur_offset = start;
5052 u64 num_bytes = end - start;
5055 while (num_bytes > 0) {
5056 alloc_size = min(num_bytes, root->fs_info->max_extent);
5057 ret = btrfs_reserve_extent(trans, root, alloc_size,
5058 root->sectorsize, 0, alloc_hint,
5064 ret = insert_reserved_file_extent(trans, inode,
5065 cur_offset, ins.objectid,
5066 ins.offset, ins.offset,
5067 ins.offset, locked_end,
5069 BTRFS_FILE_EXTENT_PREALLOC);
5071 num_bytes -= ins.offset;
5072 cur_offset += ins.offset;
5073 alloc_hint = ins.objectid + ins.offset;
5076 if (cur_offset > start) {
5077 inode->i_ctime = CURRENT_TIME;
5078 btrfs_set_flag(inode, PREALLOC);
5079 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
5080 cur_offset > i_size_read(inode))
5081 btrfs_i_size_write(inode, cur_offset);
5082 ret = btrfs_update_inode(trans, root, inode);
5089 static long btrfs_fallocate(struct inode *inode, int mode,
5090 loff_t offset, loff_t len)
5098 u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
5099 struct extent_map *em;
5100 struct btrfs_trans_handle *trans;
5103 alloc_start = offset & ~mask;
5104 alloc_end = (offset + len + mask) & ~mask;
5107 * wait for ordered IO before we have any locks. We'll loop again
5108 * below with the locks held.
5110 btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
5112 mutex_lock(&inode->i_mutex);
5113 if (alloc_start > inode->i_size) {
5114 ret = btrfs_cont_expand(inode, alloc_start);
5119 locked_end = alloc_end - 1;
5121 struct btrfs_ordered_extent *ordered;
5123 trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
5129 /* the extent lock is ordered inside the running
5132 lock_extent(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
5134 ordered = btrfs_lookup_first_ordered_extent(inode,
5137 ordered->file_offset + ordered->len > alloc_start &&
5138 ordered->file_offset < alloc_end) {
5139 btrfs_put_ordered_extent(ordered);
5140 unlock_extent(&BTRFS_I(inode)->io_tree,
5141 alloc_start, locked_end, GFP_NOFS);
5142 btrfs_end_transaction(trans, BTRFS_I(inode)->root);
5145 * we can't wait on the range with the transaction
5146 * running or with the extent lock held
5148 btrfs_wait_ordered_range(inode, alloc_start,
5149 alloc_end - alloc_start);
5152 btrfs_put_ordered_extent(ordered);
5157 cur_offset = alloc_start;
5159 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
5160 alloc_end - cur_offset, 0);
5161 BUG_ON(IS_ERR(em) || !em);
5162 last_byte = min(extent_map_end(em), alloc_end);
5163 last_byte = (last_byte + mask) & ~mask;
5164 if (em->block_start == EXTENT_MAP_HOLE) {
5165 ret = prealloc_file_range(trans, inode, cur_offset,
5166 last_byte, locked_end + 1,
5169 free_extent_map(em);
5173 if (em->block_start <= EXTENT_MAP_LAST_BYTE)
5174 alloc_hint = em->block_start;
5175 free_extent_map(em);
5177 cur_offset = last_byte;
5178 if (cur_offset >= alloc_end) {
5183 unlock_extent(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
5186 btrfs_end_transaction(trans, BTRFS_I(inode)->root);
5188 mutex_unlock(&inode->i_mutex);
5192 static int btrfs_set_page_dirty(struct page *page)
5194 return __set_page_dirty_nobuffers(page);
5197 static int btrfs_permission(struct inode *inode, int mask)
5199 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
5201 return generic_permission(inode, mask, btrfs_check_acl);
5204 static struct inode_operations btrfs_dir_inode_operations = {
5205 .getattr = btrfs_getattr,
5206 .lookup = btrfs_lookup,
5207 .create = btrfs_create,
5208 .unlink = btrfs_unlink,
5210 .mkdir = btrfs_mkdir,
5211 .rmdir = btrfs_rmdir,
5212 .rename = btrfs_rename,
5213 .symlink = btrfs_symlink,
5214 .setattr = btrfs_setattr,
5215 .mknod = btrfs_mknod,
5216 .setxattr = btrfs_setxattr,
5217 .getxattr = btrfs_getxattr,
5218 .listxattr = btrfs_listxattr,
5219 .removexattr = btrfs_removexattr,
5220 .permission = btrfs_permission,
5222 static struct inode_operations btrfs_dir_ro_inode_operations = {
5223 .lookup = btrfs_lookup,
5224 .permission = btrfs_permission,
5226 static struct file_operations btrfs_dir_file_operations = {
5227 .llseek = generic_file_llseek,
5228 .read = generic_read_dir,
5229 .readdir = btrfs_real_readdir,
5230 .unlocked_ioctl = btrfs_ioctl,
5231 #ifdef CONFIG_COMPAT
5232 .compat_ioctl = btrfs_ioctl,
5234 .release = btrfs_release_file,
5235 .fsync = btrfs_sync_file,
5238 static struct extent_io_ops btrfs_extent_io_ops = {
5239 .fill_delalloc = run_delalloc_range,
5240 .submit_bio_hook = btrfs_submit_bio_hook,
5241 .merge_bio_hook = btrfs_merge_bio_hook,
5242 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
5243 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
5244 .writepage_start_hook = btrfs_writepage_start_hook,
5245 .readpage_io_failed_hook = btrfs_io_failed_hook,
5246 .set_bit_hook = btrfs_set_bit_hook,
5247 .clear_bit_hook = btrfs_clear_bit_hook,
5251 * btrfs doesn't support the bmap operation because swapfiles
5252 * use bmap to make a mapping of extents in the file. They assume
5253 * these extents won't change over the life of the file and they
5254 * use the bmap result to do IO directly to the drive.
5256 * the btrfs bmap call would return logical addresses that aren't
5257 * suitable for IO and they also will change frequently as COW
5258 * operations happen. So, swapfile + btrfs == corruption.
5260 * For now we're avoiding this by dropping bmap.
5262 static struct address_space_operations btrfs_aops = {
5263 .readpage = btrfs_readpage,
5264 .writepage = btrfs_writepage,
5265 .writepages = btrfs_writepages,
5266 .readpages = btrfs_readpages,
5267 .sync_page = block_sync_page,
5268 .direct_IO = btrfs_direct_IO,
5269 .invalidatepage = btrfs_invalidatepage,
5270 .releasepage = btrfs_releasepage,
5271 .set_page_dirty = btrfs_set_page_dirty,
5274 static struct address_space_operations btrfs_symlink_aops = {
5275 .readpage = btrfs_readpage,
5276 .writepage = btrfs_writepage,
5277 .invalidatepage = btrfs_invalidatepage,
5278 .releasepage = btrfs_releasepage,
5281 static struct inode_operations btrfs_file_inode_operations = {
5282 .truncate = btrfs_truncate,
5283 .getattr = btrfs_getattr,
5284 .setattr = btrfs_setattr,
5285 .setxattr = btrfs_setxattr,
5286 .getxattr = btrfs_getxattr,
5287 .listxattr = btrfs_listxattr,
5288 .removexattr = btrfs_removexattr,
5289 .permission = btrfs_permission,
5290 .fallocate = btrfs_fallocate,
5291 .fiemap = btrfs_fiemap,
5293 static struct inode_operations btrfs_special_inode_operations = {
5294 .getattr = btrfs_getattr,
5295 .setattr = btrfs_setattr,
5296 .permission = btrfs_permission,
5297 .setxattr = btrfs_setxattr,
5298 .getxattr = btrfs_getxattr,
5299 .listxattr = btrfs_listxattr,
5300 .removexattr = btrfs_removexattr,
5302 static struct inode_operations btrfs_symlink_inode_operations = {
5303 .readlink = generic_readlink,
5304 .follow_link = page_follow_link_light,
5305 .put_link = page_put_link,
5306 .permission = btrfs_permission,
5307 .setxattr = btrfs_setxattr,
5308 .getxattr = btrfs_getxattr,
5309 .listxattr = btrfs_listxattr,
5310 .removexattr = btrfs_removexattr,