2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
24 #include <linux/pagemap.h>
25 #include <linux/highmem.h>
26 #include <linux/time.h>
27 #include <linux/init.h>
28 #include <linux/string.h>
29 #include <linux/backing-dev.h>
30 #include <linux/mpage.h>
31 #include <linux/swap.h>
32 #include <linux/writeback.h>
33 #include <linux/statfs.h>
34 #include <linux/compat.h>
35 #include <linux/bit_spinlock.h>
36 #include <linux/xattr.h>
37 #include <linux/posix_acl.h>
38 #include <linux/falloc.h>
39 #include <linux/slab.h>
40 #include <linux/ratelimit.h>
44 #include "transaction.h"
45 #include "btrfs_inode.h"
47 #include "print-tree.h"
49 #include "ordered-data.h"
52 #include "compression.h"
54 #include "free-space-cache.h"
55 #include "inode-map.h"
57 struct btrfs_iget_args {
59 struct btrfs_root *root;
62 static const struct inode_operations btrfs_dir_inode_operations;
63 static const struct inode_operations btrfs_symlink_inode_operations;
64 static const struct inode_operations btrfs_dir_ro_inode_operations;
65 static const struct inode_operations btrfs_special_inode_operations;
66 static const struct inode_operations btrfs_file_inode_operations;
67 static const struct address_space_operations btrfs_aops;
68 static const struct address_space_operations btrfs_symlink_aops;
69 static const struct file_operations btrfs_dir_file_operations;
70 static struct extent_io_ops btrfs_extent_io_ops;
72 static struct kmem_cache *btrfs_inode_cachep;
73 struct kmem_cache *btrfs_trans_handle_cachep;
74 struct kmem_cache *btrfs_transaction_cachep;
75 struct kmem_cache *btrfs_path_cachep;
76 struct kmem_cache *btrfs_free_space_cachep;
79 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
80 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
81 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
82 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
83 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
84 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
85 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
86 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
89 static int btrfs_setsize(struct inode *inode, loff_t newsize);
90 static int btrfs_truncate(struct inode *inode);
91 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
92 static noinline int cow_file_range(struct inode *inode,
93 struct page *locked_page,
94 u64 start, u64 end, int *page_started,
95 unsigned long *nr_written, int unlock);
97 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
98 struct inode *inode, struct inode *dir,
99 const struct qstr *qstr)
103 err = btrfs_init_acl(trans, inode, dir);
105 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
110 * this does all the hard work for inserting an inline extent into
111 * the btree. The caller should have done a btrfs_drop_extents so that
112 * no overlapping inline items exist in the btree
114 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
115 struct btrfs_root *root, struct inode *inode,
116 u64 start, size_t size, size_t compressed_size,
118 struct page **compressed_pages)
120 struct btrfs_key key;
121 struct btrfs_path *path;
122 struct extent_buffer *leaf;
123 struct page *page = NULL;
126 struct btrfs_file_extent_item *ei;
129 size_t cur_size = size;
131 unsigned long offset;
133 if (compressed_size && compressed_pages)
134 cur_size = compressed_size;
136 path = btrfs_alloc_path();
140 path->leave_spinning = 1;
141 btrfs_set_trans_block_group(trans, inode);
143 key.objectid = btrfs_ino(inode);
145 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
146 datasize = btrfs_file_extent_calc_inline_size(cur_size);
148 inode_add_bytes(inode, size);
149 ret = btrfs_insert_empty_item(trans, root, path, &key,
156 leaf = path->nodes[0];
157 ei = btrfs_item_ptr(leaf, path->slots[0],
158 struct btrfs_file_extent_item);
159 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
160 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
161 btrfs_set_file_extent_encryption(leaf, ei, 0);
162 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
163 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
164 ptr = btrfs_file_extent_inline_start(ei);
166 if (compress_type != BTRFS_COMPRESS_NONE) {
169 while (compressed_size > 0) {
170 cpage = compressed_pages[i];
171 cur_size = min_t(unsigned long, compressed_size,
174 kaddr = kmap_atomic(cpage, KM_USER0);
175 write_extent_buffer(leaf, kaddr, ptr, cur_size);
176 kunmap_atomic(kaddr, KM_USER0);
180 compressed_size -= cur_size;
182 btrfs_set_file_extent_compression(leaf, ei,
185 page = find_get_page(inode->i_mapping,
186 start >> PAGE_CACHE_SHIFT);
187 btrfs_set_file_extent_compression(leaf, ei, 0);
188 kaddr = kmap_atomic(page, KM_USER0);
189 offset = start & (PAGE_CACHE_SIZE - 1);
190 write_extent_buffer(leaf, kaddr + offset, ptr, size);
191 kunmap_atomic(kaddr, KM_USER0);
192 page_cache_release(page);
194 btrfs_mark_buffer_dirty(leaf);
195 btrfs_free_path(path);
198 * we're an inline extent, so nobody can
199 * extend the file past i_size without locking
200 * a page we already have locked.
202 * We must do any isize and inode updates
203 * before we unlock the pages. Otherwise we
204 * could end up racing with unlink.
206 BTRFS_I(inode)->disk_i_size = inode->i_size;
207 btrfs_update_inode(trans, root, inode);
211 btrfs_free_path(path);
217 * conditionally insert an inline extent into the file. This
218 * does the checks required to make sure the data is small enough
219 * to fit as an inline extent.
221 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
222 struct btrfs_root *root,
223 struct inode *inode, u64 start, u64 end,
224 size_t compressed_size, int compress_type,
225 struct page **compressed_pages)
227 u64 isize = i_size_read(inode);
228 u64 actual_end = min(end + 1, isize);
229 u64 inline_len = actual_end - start;
230 u64 aligned_end = (end + root->sectorsize - 1) &
231 ~((u64)root->sectorsize - 1);
233 u64 data_len = inline_len;
237 data_len = compressed_size;
240 actual_end >= PAGE_CACHE_SIZE ||
241 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
243 (actual_end & (root->sectorsize - 1)) == 0) ||
245 data_len > root->fs_info->max_inline) {
249 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
253 if (isize > actual_end)
254 inline_len = min_t(u64, isize, actual_end);
255 ret = insert_inline_extent(trans, root, inode, start,
256 inline_len, compressed_size,
257 compress_type, compressed_pages);
259 btrfs_delalloc_release_metadata(inode, end + 1 - start);
260 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
264 struct async_extent {
269 unsigned long nr_pages;
271 struct list_head list;
276 struct btrfs_root *root;
277 struct page *locked_page;
280 struct list_head extents;
281 struct btrfs_work work;
284 static noinline int add_async_extent(struct async_cow *cow,
285 u64 start, u64 ram_size,
288 unsigned long nr_pages,
291 struct async_extent *async_extent;
293 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
294 BUG_ON(!async_extent);
295 async_extent->start = start;
296 async_extent->ram_size = ram_size;
297 async_extent->compressed_size = compressed_size;
298 async_extent->pages = pages;
299 async_extent->nr_pages = nr_pages;
300 async_extent->compress_type = compress_type;
301 list_add_tail(&async_extent->list, &cow->extents);
306 * we create compressed extents in two phases. The first
307 * phase compresses a range of pages that have already been
308 * locked (both pages and state bits are locked).
310 * This is done inside an ordered work queue, and the compression
311 * is spread across many cpus. The actual IO submission is step
312 * two, and the ordered work queue takes care of making sure that
313 * happens in the same order things were put onto the queue by
314 * writepages and friends.
316 * If this code finds it can't get good compression, it puts an
317 * entry onto the work queue to write the uncompressed bytes. This
318 * makes sure that both compressed inodes and uncompressed inodes
319 * are written in the same order that pdflush sent them down.
321 static noinline int compress_file_range(struct inode *inode,
322 struct page *locked_page,
324 struct async_cow *async_cow,
327 struct btrfs_root *root = BTRFS_I(inode)->root;
328 struct btrfs_trans_handle *trans;
330 u64 blocksize = root->sectorsize;
332 u64 isize = i_size_read(inode);
334 struct page **pages = NULL;
335 unsigned long nr_pages;
336 unsigned long nr_pages_ret = 0;
337 unsigned long total_compressed = 0;
338 unsigned long total_in = 0;
339 unsigned long max_compressed = 128 * 1024;
340 unsigned long max_uncompressed = 128 * 1024;
343 int compress_type = root->fs_info->compress_type;
345 actual_end = min_t(u64, isize, end + 1);
348 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
349 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
352 * we don't want to send crud past the end of i_size through
353 * compression, that's just a waste of CPU time. So, if the
354 * end of the file is before the start of our current
355 * requested range of bytes, we bail out to the uncompressed
356 * cleanup code that can deal with all of this.
358 * It isn't really the fastest way to fix things, but this is a
359 * very uncommon corner.
361 if (actual_end <= start)
362 goto cleanup_and_bail_uncompressed;
364 total_compressed = actual_end - start;
366 /* we want to make sure that amount of ram required to uncompress
367 * an extent is reasonable, so we limit the total size in ram
368 * of a compressed extent to 128k. This is a crucial number
369 * because it also controls how easily we can spread reads across
370 * cpus for decompression.
372 * We also want to make sure the amount of IO required to do
373 * a random read is reasonably small, so we limit the size of
374 * a compressed extent to 128k.
376 total_compressed = min(total_compressed, max_uncompressed);
377 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
378 num_bytes = max(blocksize, num_bytes);
383 * we do compression for mount -o compress and when the
384 * inode has not been flagged as nocompress. This flag can
385 * change at any time if we discover bad compression ratios.
387 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
388 (btrfs_test_opt(root, COMPRESS) ||
389 (BTRFS_I(inode)->force_compress) ||
390 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
392 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
395 if (BTRFS_I(inode)->force_compress)
396 compress_type = BTRFS_I(inode)->force_compress;
398 ret = btrfs_compress_pages(compress_type,
399 inode->i_mapping, start,
400 total_compressed, pages,
401 nr_pages, &nr_pages_ret,
407 unsigned long offset = total_compressed &
408 (PAGE_CACHE_SIZE - 1);
409 struct page *page = pages[nr_pages_ret - 1];
412 /* zero the tail end of the last page, we might be
413 * sending it down to disk
416 kaddr = kmap_atomic(page, KM_USER0);
417 memset(kaddr + offset, 0,
418 PAGE_CACHE_SIZE - offset);
419 kunmap_atomic(kaddr, KM_USER0);
425 trans = btrfs_join_transaction(root, 1);
426 BUG_ON(IS_ERR(trans));
427 btrfs_set_trans_block_group(trans, inode);
428 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
430 /* lets try to make an inline extent */
431 if (ret || total_in < (actual_end - start)) {
432 /* we didn't compress the entire range, try
433 * to make an uncompressed inline extent.
435 ret = cow_file_range_inline(trans, root, inode,
436 start, end, 0, 0, NULL);
438 /* try making a compressed inline extent */
439 ret = cow_file_range_inline(trans, root, inode,
442 compress_type, pages);
446 * inline extent creation worked, we don't need
447 * to create any more async work items. Unlock
448 * and free up our temp pages.
450 extent_clear_unlock_delalloc(inode,
451 &BTRFS_I(inode)->io_tree,
453 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
454 EXTENT_CLEAR_DELALLOC |
455 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
457 btrfs_end_transaction(trans, root);
460 btrfs_end_transaction(trans, root);
465 * we aren't doing an inline extent round the compressed size
466 * up to a block size boundary so the allocator does sane
469 total_compressed = (total_compressed + blocksize - 1) &
473 * one last check to make sure the compression is really a
474 * win, compare the page count read with the blocks on disk
476 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
477 ~(PAGE_CACHE_SIZE - 1);
478 if (total_compressed >= total_in) {
481 num_bytes = total_in;
484 if (!will_compress && pages) {
486 * the compression code ran but failed to make things smaller,
487 * free any pages it allocated and our page pointer array
489 for (i = 0; i < nr_pages_ret; i++) {
490 WARN_ON(pages[i]->mapping);
491 page_cache_release(pages[i]);
495 total_compressed = 0;
498 /* flag the file so we don't compress in the future */
499 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
500 !(BTRFS_I(inode)->force_compress)) {
501 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
507 /* the async work queues will take care of doing actual
508 * allocation on disk for these compressed pages,
509 * and will submit them to the elevator.
511 add_async_extent(async_cow, start, num_bytes,
512 total_compressed, pages, nr_pages_ret,
515 if (start + num_bytes < end) {
522 cleanup_and_bail_uncompressed:
524 * No compression, but we still need to write the pages in
525 * the file we've been given so far. redirty the locked
526 * page if it corresponds to our extent and set things up
527 * for the async work queue to run cow_file_range to do
528 * the normal delalloc dance
530 if (page_offset(locked_page) >= start &&
531 page_offset(locked_page) <= end) {
532 __set_page_dirty_nobuffers(locked_page);
533 /* unlocked later on in the async handlers */
535 add_async_extent(async_cow, start, end - start + 1,
536 0, NULL, 0, BTRFS_COMPRESS_NONE);
544 for (i = 0; i < nr_pages_ret; i++) {
545 WARN_ON(pages[i]->mapping);
546 page_cache_release(pages[i]);
554 * phase two of compressed writeback. This is the ordered portion
555 * of the code, which only gets called in the order the work was
556 * queued. We walk all the async extents created by compress_file_range
557 * and send them down to the disk.
559 static noinline int submit_compressed_extents(struct inode *inode,
560 struct async_cow *async_cow)
562 struct async_extent *async_extent;
564 struct btrfs_trans_handle *trans;
565 struct btrfs_key ins;
566 struct extent_map *em;
567 struct btrfs_root *root = BTRFS_I(inode)->root;
568 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
569 struct extent_io_tree *io_tree;
572 if (list_empty(&async_cow->extents))
576 while (!list_empty(&async_cow->extents)) {
577 async_extent = list_entry(async_cow->extents.next,
578 struct async_extent, list);
579 list_del(&async_extent->list);
581 io_tree = &BTRFS_I(inode)->io_tree;
584 /* did the compression code fall back to uncompressed IO? */
585 if (!async_extent->pages) {
586 int page_started = 0;
587 unsigned long nr_written = 0;
589 lock_extent(io_tree, async_extent->start,
590 async_extent->start +
591 async_extent->ram_size - 1, GFP_NOFS);
593 /* allocate blocks */
594 ret = cow_file_range(inode, async_cow->locked_page,
596 async_extent->start +
597 async_extent->ram_size - 1,
598 &page_started, &nr_written, 0);
601 * if page_started, cow_file_range inserted an
602 * inline extent and took care of all the unlocking
603 * and IO for us. Otherwise, we need to submit
604 * all those pages down to the drive.
606 if (!page_started && !ret)
607 extent_write_locked_range(io_tree,
608 inode, async_extent->start,
609 async_extent->start +
610 async_extent->ram_size - 1,
618 lock_extent(io_tree, async_extent->start,
619 async_extent->start + async_extent->ram_size - 1,
622 trans = btrfs_join_transaction(root, 1);
623 BUG_ON(IS_ERR(trans));
624 ret = btrfs_reserve_extent(trans, root,
625 async_extent->compressed_size,
626 async_extent->compressed_size,
629 btrfs_end_transaction(trans, root);
633 for (i = 0; i < async_extent->nr_pages; i++) {
634 WARN_ON(async_extent->pages[i]->mapping);
635 page_cache_release(async_extent->pages[i]);
637 kfree(async_extent->pages);
638 async_extent->nr_pages = 0;
639 async_extent->pages = NULL;
640 unlock_extent(io_tree, async_extent->start,
641 async_extent->start +
642 async_extent->ram_size - 1, GFP_NOFS);
647 * here we're doing allocation and writeback of the
650 btrfs_drop_extent_cache(inode, async_extent->start,
651 async_extent->start +
652 async_extent->ram_size - 1, 0);
654 em = alloc_extent_map();
656 em->start = async_extent->start;
657 em->len = async_extent->ram_size;
658 em->orig_start = em->start;
660 em->block_start = ins.objectid;
661 em->block_len = ins.offset;
662 em->bdev = root->fs_info->fs_devices->latest_bdev;
663 em->compress_type = async_extent->compress_type;
664 set_bit(EXTENT_FLAG_PINNED, &em->flags);
665 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
668 write_lock(&em_tree->lock);
669 ret = add_extent_mapping(em_tree, em);
670 write_unlock(&em_tree->lock);
671 if (ret != -EEXIST) {
675 btrfs_drop_extent_cache(inode, async_extent->start,
676 async_extent->start +
677 async_extent->ram_size - 1, 0);
680 ret = btrfs_add_ordered_extent_compress(inode,
683 async_extent->ram_size,
685 BTRFS_ORDERED_COMPRESSED,
686 async_extent->compress_type);
690 * clear dirty, set writeback and unlock the pages.
692 extent_clear_unlock_delalloc(inode,
693 &BTRFS_I(inode)->io_tree,
695 async_extent->start +
696 async_extent->ram_size - 1,
697 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
698 EXTENT_CLEAR_UNLOCK |
699 EXTENT_CLEAR_DELALLOC |
700 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
702 ret = btrfs_submit_compressed_write(inode,
704 async_extent->ram_size,
706 ins.offset, async_extent->pages,
707 async_extent->nr_pages);
710 alloc_hint = ins.objectid + ins.offset;
718 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
721 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
722 struct extent_map *em;
725 read_lock(&em_tree->lock);
726 em = search_extent_mapping(em_tree, start, num_bytes);
729 * if block start isn't an actual block number then find the
730 * first block in this inode and use that as a hint. If that
731 * block is also bogus then just don't worry about it.
733 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
735 em = search_extent_mapping(em_tree, 0, 0);
736 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
737 alloc_hint = em->block_start;
741 alloc_hint = em->block_start;
745 read_unlock(&em_tree->lock);
750 static inline bool is_free_space_inode(struct btrfs_root *root,
753 if (root == root->fs_info->tree_root ||
754 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
760 * when extent_io.c finds a delayed allocation range in the file,
761 * the call backs end up in this code. The basic idea is to
762 * allocate extents on disk for the range, and create ordered data structs
763 * in ram to track those extents.
765 * locked_page is the page that writepage had locked already. We use
766 * it to make sure we don't do extra locks or unlocks.
768 * *page_started is set to one if we unlock locked_page and do everything
769 * required to start IO on it. It may be clean and already done with
772 static noinline int cow_file_range(struct inode *inode,
773 struct page *locked_page,
774 u64 start, u64 end, int *page_started,
775 unsigned long *nr_written,
778 struct btrfs_root *root = BTRFS_I(inode)->root;
779 struct btrfs_trans_handle *trans;
782 unsigned long ram_size;
785 u64 blocksize = root->sectorsize;
786 struct btrfs_key ins;
787 struct extent_map *em;
788 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
791 BUG_ON(is_free_space_inode(root, inode));
792 trans = btrfs_join_transaction(root, 1);
793 BUG_ON(IS_ERR(trans));
794 btrfs_set_trans_block_group(trans, inode);
795 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
797 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
798 num_bytes = max(blocksize, num_bytes);
799 disk_num_bytes = num_bytes;
803 /* lets try to make an inline extent */
804 ret = cow_file_range_inline(trans, root, inode,
805 start, end, 0, 0, NULL);
807 extent_clear_unlock_delalloc(inode,
808 &BTRFS_I(inode)->io_tree,
810 EXTENT_CLEAR_UNLOCK_PAGE |
811 EXTENT_CLEAR_UNLOCK |
812 EXTENT_CLEAR_DELALLOC |
814 EXTENT_SET_WRITEBACK |
815 EXTENT_END_WRITEBACK);
817 *nr_written = *nr_written +
818 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
825 BUG_ON(disk_num_bytes >
826 btrfs_super_total_bytes(&root->fs_info->super_copy));
828 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
829 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
831 while (disk_num_bytes > 0) {
834 cur_alloc_size = disk_num_bytes;
835 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
836 root->sectorsize, 0, alloc_hint,
840 em = alloc_extent_map();
843 em->orig_start = em->start;
844 ram_size = ins.offset;
845 em->len = ins.offset;
847 em->block_start = ins.objectid;
848 em->block_len = ins.offset;
849 em->bdev = root->fs_info->fs_devices->latest_bdev;
850 set_bit(EXTENT_FLAG_PINNED, &em->flags);
853 write_lock(&em_tree->lock);
854 ret = add_extent_mapping(em_tree, em);
855 write_unlock(&em_tree->lock);
856 if (ret != -EEXIST) {
860 btrfs_drop_extent_cache(inode, start,
861 start + ram_size - 1, 0);
864 cur_alloc_size = ins.offset;
865 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
866 ram_size, cur_alloc_size, 0);
869 if (root->root_key.objectid ==
870 BTRFS_DATA_RELOC_TREE_OBJECTID) {
871 ret = btrfs_reloc_clone_csums(inode, start,
876 if (disk_num_bytes < cur_alloc_size)
879 /* we're not doing compressed IO, don't unlock the first
880 * page (which the caller expects to stay locked), don't
881 * clear any dirty bits and don't set any writeback bits
883 * Do set the Private2 bit so we know this page was properly
884 * setup for writepage
886 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
887 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
890 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
891 start, start + ram_size - 1,
893 disk_num_bytes -= cur_alloc_size;
894 num_bytes -= cur_alloc_size;
895 alloc_hint = ins.objectid + ins.offset;
896 start += cur_alloc_size;
900 btrfs_end_transaction(trans, root);
906 * work queue call back to started compression on a file and pages
908 static noinline void async_cow_start(struct btrfs_work *work)
910 struct async_cow *async_cow;
912 async_cow = container_of(work, struct async_cow, work);
914 compress_file_range(async_cow->inode, async_cow->locked_page,
915 async_cow->start, async_cow->end, async_cow,
918 async_cow->inode = NULL;
922 * work queue call back to submit previously compressed pages
924 static noinline void async_cow_submit(struct btrfs_work *work)
926 struct async_cow *async_cow;
927 struct btrfs_root *root;
928 unsigned long nr_pages;
930 async_cow = container_of(work, struct async_cow, work);
932 root = async_cow->root;
933 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
936 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
938 if (atomic_read(&root->fs_info->async_delalloc_pages) <
940 waitqueue_active(&root->fs_info->async_submit_wait))
941 wake_up(&root->fs_info->async_submit_wait);
943 if (async_cow->inode)
944 submit_compressed_extents(async_cow->inode, async_cow);
947 static noinline void async_cow_free(struct btrfs_work *work)
949 struct async_cow *async_cow;
950 async_cow = container_of(work, struct async_cow, work);
954 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
955 u64 start, u64 end, int *page_started,
956 unsigned long *nr_written)
958 struct async_cow *async_cow;
959 struct btrfs_root *root = BTRFS_I(inode)->root;
960 unsigned long nr_pages;
962 int limit = 10 * 1024 * 1042;
964 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
965 1, 0, NULL, GFP_NOFS);
966 while (start < end) {
967 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
969 async_cow->inode = inode;
970 async_cow->root = root;
971 async_cow->locked_page = locked_page;
972 async_cow->start = start;
974 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
977 cur_end = min(end, start + 512 * 1024 - 1);
979 async_cow->end = cur_end;
980 INIT_LIST_HEAD(&async_cow->extents);
982 async_cow->work.func = async_cow_start;
983 async_cow->work.ordered_func = async_cow_submit;
984 async_cow->work.ordered_free = async_cow_free;
985 async_cow->work.flags = 0;
987 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
989 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
991 btrfs_queue_worker(&root->fs_info->delalloc_workers,
994 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
995 wait_event(root->fs_info->async_submit_wait,
996 (atomic_read(&root->fs_info->async_delalloc_pages) <
1000 while (atomic_read(&root->fs_info->async_submit_draining) &&
1001 atomic_read(&root->fs_info->async_delalloc_pages)) {
1002 wait_event(root->fs_info->async_submit_wait,
1003 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1007 *nr_written += nr_pages;
1008 start = cur_end + 1;
1014 static noinline int csum_exist_in_range(struct btrfs_root *root,
1015 u64 bytenr, u64 num_bytes)
1018 struct btrfs_ordered_sum *sums;
1021 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1022 bytenr + num_bytes - 1, &list);
1023 if (ret == 0 && list_empty(&list))
1026 while (!list_empty(&list)) {
1027 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1028 list_del(&sums->list);
1035 * when nowcow writeback call back. This checks for snapshots or COW copies
1036 * of the extents that exist in the file, and COWs the file as required.
1038 * If no cow copies or snapshots exist, we write directly to the existing
1041 static noinline int run_delalloc_nocow(struct inode *inode,
1042 struct page *locked_page,
1043 u64 start, u64 end, int *page_started, int force,
1044 unsigned long *nr_written)
1046 struct btrfs_root *root = BTRFS_I(inode)->root;
1047 struct btrfs_trans_handle *trans;
1048 struct extent_buffer *leaf;
1049 struct btrfs_path *path;
1050 struct btrfs_file_extent_item *fi;
1051 struct btrfs_key found_key;
1064 u64 ino = btrfs_ino(inode);
1066 path = btrfs_alloc_path();
1069 nolock = is_free_space_inode(root, inode);
1072 trans = btrfs_join_transaction_nolock(root, 1);
1074 trans = btrfs_join_transaction(root, 1);
1075 BUG_ON(IS_ERR(trans));
1077 cow_start = (u64)-1;
1080 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1083 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1084 leaf = path->nodes[0];
1085 btrfs_item_key_to_cpu(leaf, &found_key,
1086 path->slots[0] - 1);
1087 if (found_key.objectid == ino &&
1088 found_key.type == BTRFS_EXTENT_DATA_KEY)
1093 leaf = path->nodes[0];
1094 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1095 ret = btrfs_next_leaf(root, path);
1100 leaf = path->nodes[0];
1106 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1108 if (found_key.objectid > ino ||
1109 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1110 found_key.offset > end)
1113 if (found_key.offset > cur_offset) {
1114 extent_end = found_key.offset;
1119 fi = btrfs_item_ptr(leaf, path->slots[0],
1120 struct btrfs_file_extent_item);
1121 extent_type = btrfs_file_extent_type(leaf, fi);
1123 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1124 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1125 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1126 extent_offset = btrfs_file_extent_offset(leaf, fi);
1127 extent_end = found_key.offset +
1128 btrfs_file_extent_num_bytes(leaf, fi);
1129 if (extent_end <= start) {
1133 if (disk_bytenr == 0)
1135 if (btrfs_file_extent_compression(leaf, fi) ||
1136 btrfs_file_extent_encryption(leaf, fi) ||
1137 btrfs_file_extent_other_encoding(leaf, fi))
1139 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1141 if (btrfs_extent_readonly(root, disk_bytenr))
1143 if (btrfs_cross_ref_exist(trans, root, ino,
1145 extent_offset, disk_bytenr))
1147 disk_bytenr += extent_offset;
1148 disk_bytenr += cur_offset - found_key.offset;
1149 num_bytes = min(end + 1, extent_end) - cur_offset;
1151 * force cow if csum exists in the range.
1152 * this ensure that csum for a given extent are
1153 * either valid or do not exist.
1155 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1158 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1159 extent_end = found_key.offset +
1160 btrfs_file_extent_inline_len(leaf, fi);
1161 extent_end = ALIGN(extent_end, root->sectorsize);
1166 if (extent_end <= start) {
1171 if (cow_start == (u64)-1)
1172 cow_start = cur_offset;
1173 cur_offset = extent_end;
1174 if (cur_offset > end)
1180 btrfs_release_path(path);
1181 if (cow_start != (u64)-1) {
1182 ret = cow_file_range(inode, locked_page, cow_start,
1183 found_key.offset - 1, page_started,
1186 cow_start = (u64)-1;
1189 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1190 struct extent_map *em;
1191 struct extent_map_tree *em_tree;
1192 em_tree = &BTRFS_I(inode)->extent_tree;
1193 em = alloc_extent_map();
1195 em->start = cur_offset;
1196 em->orig_start = em->start;
1197 em->len = num_bytes;
1198 em->block_len = num_bytes;
1199 em->block_start = disk_bytenr;
1200 em->bdev = root->fs_info->fs_devices->latest_bdev;
1201 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1203 write_lock(&em_tree->lock);
1204 ret = add_extent_mapping(em_tree, em);
1205 write_unlock(&em_tree->lock);
1206 if (ret != -EEXIST) {
1207 free_extent_map(em);
1210 btrfs_drop_extent_cache(inode, em->start,
1211 em->start + em->len - 1, 0);
1213 type = BTRFS_ORDERED_PREALLOC;
1215 type = BTRFS_ORDERED_NOCOW;
1218 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1219 num_bytes, num_bytes, type);
1222 if (root->root_key.objectid ==
1223 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1224 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1229 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1230 cur_offset, cur_offset + num_bytes - 1,
1231 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1232 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1233 EXTENT_SET_PRIVATE2);
1234 cur_offset = extent_end;
1235 if (cur_offset > end)
1238 btrfs_release_path(path);
1240 if (cur_offset <= end && cow_start == (u64)-1)
1241 cow_start = cur_offset;
1242 if (cow_start != (u64)-1) {
1243 ret = cow_file_range(inode, locked_page, cow_start, end,
1244 page_started, nr_written, 1);
1249 ret = btrfs_end_transaction_nolock(trans, root);
1252 ret = btrfs_end_transaction(trans, root);
1255 btrfs_free_path(path);
1260 * extent_io.c call back to do delayed allocation processing
1262 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1263 u64 start, u64 end, int *page_started,
1264 unsigned long *nr_written)
1267 struct btrfs_root *root = BTRFS_I(inode)->root;
1269 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1270 ret = run_delalloc_nocow(inode, locked_page, start, end,
1271 page_started, 1, nr_written);
1272 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1273 ret = run_delalloc_nocow(inode, locked_page, start, end,
1274 page_started, 0, nr_written);
1275 else if (!btrfs_test_opt(root, COMPRESS) &&
1276 !(BTRFS_I(inode)->force_compress) &&
1277 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
1278 ret = cow_file_range(inode, locked_page, start, end,
1279 page_started, nr_written, 1);
1281 ret = cow_file_range_async(inode, locked_page, start, end,
1282 page_started, nr_written);
1286 static int btrfs_split_extent_hook(struct inode *inode,
1287 struct extent_state *orig, u64 split)
1289 /* not delalloc, ignore it */
1290 if (!(orig->state & EXTENT_DELALLOC))
1293 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
1298 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1299 * extents so we can keep track of new extents that are just merged onto old
1300 * extents, such as when we are doing sequential writes, so we can properly
1301 * account for the metadata space we'll need.
1303 static int btrfs_merge_extent_hook(struct inode *inode,
1304 struct extent_state *new,
1305 struct extent_state *other)
1307 /* not delalloc, ignore it */
1308 if (!(other->state & EXTENT_DELALLOC))
1311 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
1316 * extent_io.c set_bit_hook, used to track delayed allocation
1317 * bytes in this file, and to maintain the list of inodes that
1318 * have pending delalloc work to be done.
1320 static int btrfs_set_bit_hook(struct inode *inode,
1321 struct extent_state *state, int *bits)
1325 * set_bit and clear bit hooks normally require _irqsave/restore
1326 * but in this case, we are only testeing for the DELALLOC
1327 * bit, which is only set or cleared with irqs on
1329 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1330 struct btrfs_root *root = BTRFS_I(inode)->root;
1331 u64 len = state->end + 1 - state->start;
1332 bool do_list = !is_free_space_inode(root, inode);
1334 if (*bits & EXTENT_FIRST_DELALLOC)
1335 *bits &= ~EXTENT_FIRST_DELALLOC;
1337 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
1339 spin_lock(&root->fs_info->delalloc_lock);
1340 BTRFS_I(inode)->delalloc_bytes += len;
1341 root->fs_info->delalloc_bytes += len;
1342 if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1343 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1344 &root->fs_info->delalloc_inodes);
1346 spin_unlock(&root->fs_info->delalloc_lock);
1352 * extent_io.c clear_bit_hook, see set_bit_hook for why
1354 static int btrfs_clear_bit_hook(struct inode *inode,
1355 struct extent_state *state, int *bits)
1358 * set_bit and clear bit hooks normally require _irqsave/restore
1359 * but in this case, we are only testeing for the DELALLOC
1360 * bit, which is only set or cleared with irqs on
1362 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1363 struct btrfs_root *root = BTRFS_I(inode)->root;
1364 u64 len = state->end + 1 - state->start;
1365 bool do_list = !is_free_space_inode(root, inode);
1367 if (*bits & EXTENT_FIRST_DELALLOC)
1368 *bits &= ~EXTENT_FIRST_DELALLOC;
1369 else if (!(*bits & EXTENT_DO_ACCOUNTING))
1370 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
1372 if (*bits & EXTENT_DO_ACCOUNTING)
1373 btrfs_delalloc_release_metadata(inode, len);
1375 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1377 btrfs_free_reserved_data_space(inode, len);
1379 spin_lock(&root->fs_info->delalloc_lock);
1380 root->fs_info->delalloc_bytes -= len;
1381 BTRFS_I(inode)->delalloc_bytes -= len;
1383 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1384 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1385 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1387 spin_unlock(&root->fs_info->delalloc_lock);
1393 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1394 * we don't create bios that span stripes or chunks
1396 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1397 size_t size, struct bio *bio,
1398 unsigned long bio_flags)
1400 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1401 struct btrfs_mapping_tree *map_tree;
1402 u64 logical = (u64)bio->bi_sector << 9;
1407 if (bio_flags & EXTENT_BIO_COMPRESSED)
1410 length = bio->bi_size;
1411 map_tree = &root->fs_info->mapping_tree;
1412 map_length = length;
1413 ret = btrfs_map_block(map_tree, READ, logical,
1414 &map_length, NULL, 0);
1416 if (map_length < length + size)
1422 * in order to insert checksums into the metadata in large chunks,
1423 * we wait until bio submission time. All the pages in the bio are
1424 * checksummed and sums are attached onto the ordered extent record.
1426 * At IO completion time the cums attached on the ordered extent record
1427 * are inserted into the btree
1429 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1430 struct bio *bio, int mirror_num,
1431 unsigned long bio_flags,
1434 struct btrfs_root *root = BTRFS_I(inode)->root;
1437 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1443 * in order to insert checksums into the metadata in large chunks,
1444 * we wait until bio submission time. All the pages in the bio are
1445 * checksummed and sums are attached onto the ordered extent record.
1447 * At IO completion time the cums attached on the ordered extent record
1448 * are inserted into the btree
1450 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1451 int mirror_num, unsigned long bio_flags,
1454 struct btrfs_root *root = BTRFS_I(inode)->root;
1455 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1459 * extent_io.c submission hook. This does the right thing for csum calculation
1460 * on write, or reading the csums from the tree before a read
1462 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1463 int mirror_num, unsigned long bio_flags,
1466 struct btrfs_root *root = BTRFS_I(inode)->root;
1470 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1472 if (is_free_space_inode(root, inode))
1473 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
1475 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1478 if (!(rw & REQ_WRITE)) {
1479 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1480 return btrfs_submit_compressed_read(inode, bio,
1481 mirror_num, bio_flags);
1482 } else if (!skip_sum) {
1483 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1488 } else if (!skip_sum) {
1489 /* csum items have already been cloned */
1490 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1492 /* we're doing a write, do the async checksumming */
1493 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1494 inode, rw, bio, mirror_num,
1495 bio_flags, bio_offset,
1496 __btrfs_submit_bio_start,
1497 __btrfs_submit_bio_done);
1501 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1505 * given a list of ordered sums record them in the inode. This happens
1506 * at IO completion time based on sums calculated at bio submission time.
1508 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1509 struct inode *inode, u64 file_offset,
1510 struct list_head *list)
1512 struct btrfs_ordered_sum *sum;
1514 btrfs_set_trans_block_group(trans, inode);
1516 list_for_each_entry(sum, list, list) {
1517 btrfs_csum_file_blocks(trans,
1518 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1523 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1524 struct extent_state **cached_state)
1526 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1528 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1529 cached_state, GFP_NOFS);
1532 /* see btrfs_writepage_start_hook for details on why this is required */
1533 struct btrfs_writepage_fixup {
1535 struct btrfs_work work;
1538 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1540 struct btrfs_writepage_fixup *fixup;
1541 struct btrfs_ordered_extent *ordered;
1542 struct extent_state *cached_state = NULL;
1544 struct inode *inode;
1548 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1552 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1553 ClearPageChecked(page);
1557 inode = page->mapping->host;
1558 page_start = page_offset(page);
1559 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1561 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1562 &cached_state, GFP_NOFS);
1564 /* already ordered? We're done */
1565 if (PagePrivate2(page))
1568 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1570 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1571 page_end, &cached_state, GFP_NOFS);
1573 btrfs_start_ordered_extent(inode, ordered, 1);
1578 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1579 ClearPageChecked(page);
1581 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1582 &cached_state, GFP_NOFS);
1585 page_cache_release(page);
1590 * There are a few paths in the higher layers of the kernel that directly
1591 * set the page dirty bit without asking the filesystem if it is a
1592 * good idea. This causes problems because we want to make sure COW
1593 * properly happens and the data=ordered rules are followed.
1595 * In our case any range that doesn't have the ORDERED bit set
1596 * hasn't been properly setup for IO. We kick off an async process
1597 * to fix it up. The async helper will wait for ordered extents, set
1598 * the delalloc bit and make it safe to write the page.
1600 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1602 struct inode *inode = page->mapping->host;
1603 struct btrfs_writepage_fixup *fixup;
1604 struct btrfs_root *root = BTRFS_I(inode)->root;
1606 /* this page is properly in the ordered list */
1607 if (TestClearPagePrivate2(page))
1610 if (PageChecked(page))
1613 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1617 SetPageChecked(page);
1618 page_cache_get(page);
1619 fixup->work.func = btrfs_writepage_fixup_worker;
1621 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1625 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1626 struct inode *inode, u64 file_pos,
1627 u64 disk_bytenr, u64 disk_num_bytes,
1628 u64 num_bytes, u64 ram_bytes,
1629 u8 compression, u8 encryption,
1630 u16 other_encoding, int extent_type)
1632 struct btrfs_root *root = BTRFS_I(inode)->root;
1633 struct btrfs_file_extent_item *fi;
1634 struct btrfs_path *path;
1635 struct extent_buffer *leaf;
1636 struct btrfs_key ins;
1640 path = btrfs_alloc_path();
1643 path->leave_spinning = 1;
1646 * we may be replacing one extent in the tree with another.
1647 * The new extent is pinned in the extent map, and we don't want
1648 * to drop it from the cache until it is completely in the btree.
1650 * So, tell btrfs_drop_extents to leave this extent in the cache.
1651 * the caller is expected to unpin it and allow it to be merged
1654 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1658 ins.objectid = btrfs_ino(inode);
1659 ins.offset = file_pos;
1660 ins.type = BTRFS_EXTENT_DATA_KEY;
1661 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1663 leaf = path->nodes[0];
1664 fi = btrfs_item_ptr(leaf, path->slots[0],
1665 struct btrfs_file_extent_item);
1666 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1667 btrfs_set_file_extent_type(leaf, fi, extent_type);
1668 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1669 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1670 btrfs_set_file_extent_offset(leaf, fi, 0);
1671 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1672 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1673 btrfs_set_file_extent_compression(leaf, fi, compression);
1674 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1675 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1677 btrfs_unlock_up_safe(path, 1);
1678 btrfs_set_lock_blocking(leaf);
1680 btrfs_mark_buffer_dirty(leaf);
1682 inode_add_bytes(inode, num_bytes);
1684 ins.objectid = disk_bytenr;
1685 ins.offset = disk_num_bytes;
1686 ins.type = BTRFS_EXTENT_ITEM_KEY;
1687 ret = btrfs_alloc_reserved_file_extent(trans, root,
1688 root->root_key.objectid,
1689 btrfs_ino(inode), file_pos, &ins);
1691 btrfs_free_path(path);
1697 * helper function for btrfs_finish_ordered_io, this
1698 * just reads in some of the csum leaves to prime them into ram
1699 * before we start the transaction. It limits the amount of btree
1700 * reads required while inside the transaction.
1702 /* as ordered data IO finishes, this gets called so we can finish
1703 * an ordered extent if the range of bytes in the file it covers are
1706 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1708 struct btrfs_root *root = BTRFS_I(inode)->root;
1709 struct btrfs_trans_handle *trans = NULL;
1710 struct btrfs_ordered_extent *ordered_extent = NULL;
1711 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1712 struct extent_state *cached_state = NULL;
1713 int compress_type = 0;
1717 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1721 BUG_ON(!ordered_extent);
1723 nolock = is_free_space_inode(root, inode);
1725 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1726 BUG_ON(!list_empty(&ordered_extent->list));
1727 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1730 trans = btrfs_join_transaction_nolock(root, 1);
1732 trans = btrfs_join_transaction(root, 1);
1733 BUG_ON(IS_ERR(trans));
1734 btrfs_set_trans_block_group(trans, inode);
1735 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1736 ret = btrfs_update_inode(trans, root, inode);
1742 lock_extent_bits(io_tree, ordered_extent->file_offset,
1743 ordered_extent->file_offset + ordered_extent->len - 1,
1744 0, &cached_state, GFP_NOFS);
1747 trans = btrfs_join_transaction_nolock(root, 1);
1749 trans = btrfs_join_transaction(root, 1);
1750 BUG_ON(IS_ERR(trans));
1751 btrfs_set_trans_block_group(trans, inode);
1752 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1754 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1755 compress_type = ordered_extent->compress_type;
1756 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1757 BUG_ON(compress_type);
1758 ret = btrfs_mark_extent_written(trans, inode,
1759 ordered_extent->file_offset,
1760 ordered_extent->file_offset +
1761 ordered_extent->len);
1764 BUG_ON(root == root->fs_info->tree_root);
1765 ret = insert_reserved_file_extent(trans, inode,
1766 ordered_extent->file_offset,
1767 ordered_extent->start,
1768 ordered_extent->disk_len,
1769 ordered_extent->len,
1770 ordered_extent->len,
1771 compress_type, 0, 0,
1772 BTRFS_FILE_EXTENT_REG);
1773 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1774 ordered_extent->file_offset,
1775 ordered_extent->len);
1778 unlock_extent_cached(io_tree, ordered_extent->file_offset,
1779 ordered_extent->file_offset +
1780 ordered_extent->len - 1, &cached_state, GFP_NOFS);
1782 add_pending_csums(trans, inode, ordered_extent->file_offset,
1783 &ordered_extent->list);
1785 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1787 ret = btrfs_update_inode(trans, root, inode);
1794 btrfs_end_transaction_nolock(trans, root);
1796 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
1798 btrfs_end_transaction(trans, root);
1802 btrfs_put_ordered_extent(ordered_extent);
1803 /* once for the tree */
1804 btrfs_put_ordered_extent(ordered_extent);
1809 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1810 struct extent_state *state, int uptodate)
1812 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
1814 ClearPagePrivate2(page);
1815 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1819 * When IO fails, either with EIO or csum verification fails, we
1820 * try other mirrors that might have a good copy of the data. This
1821 * io_failure_record is used to record state as we go through all the
1822 * mirrors. If another mirror has good data, the page is set up to date
1823 * and things continue. If a good mirror can't be found, the original
1824 * bio end_io callback is called to indicate things have failed.
1826 struct io_failure_record {
1831 unsigned long bio_flags;
1835 static int btrfs_io_failed_hook(struct bio *failed_bio,
1836 struct page *page, u64 start, u64 end,
1837 struct extent_state *state)
1839 struct io_failure_record *failrec = NULL;
1841 struct extent_map *em;
1842 struct inode *inode = page->mapping->host;
1843 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1844 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1851 ret = get_state_private(failure_tree, start, &private);
1853 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
1856 failrec->start = start;
1857 failrec->len = end - start + 1;
1858 failrec->last_mirror = 0;
1859 failrec->bio_flags = 0;
1861 read_lock(&em_tree->lock);
1862 em = lookup_extent_mapping(em_tree, start, failrec->len);
1863 if (em->start > start || em->start + em->len < start) {
1864 free_extent_map(em);
1867 read_unlock(&em_tree->lock);
1869 if (IS_ERR_OR_NULL(em)) {
1873 logical = start - em->start;
1874 logical = em->block_start + logical;
1875 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
1876 logical = em->block_start;
1877 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
1878 extent_set_compress_type(&failrec->bio_flags,
1881 failrec->logical = logical;
1882 free_extent_map(em);
1883 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
1884 EXTENT_DIRTY, GFP_NOFS);
1885 set_state_private(failure_tree, start,
1886 (u64)(unsigned long)failrec);
1888 failrec = (struct io_failure_record *)(unsigned long)private;
1890 num_copies = btrfs_num_copies(
1891 &BTRFS_I(inode)->root->fs_info->mapping_tree,
1892 failrec->logical, failrec->len);
1893 failrec->last_mirror++;
1895 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1896 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1899 if (state && state->start != failrec->start)
1901 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1903 if (!state || failrec->last_mirror > num_copies) {
1904 set_state_private(failure_tree, failrec->start, 0);
1905 clear_extent_bits(failure_tree, failrec->start,
1906 failrec->start + failrec->len - 1,
1907 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1911 bio = bio_alloc(GFP_NOFS, 1);
1912 bio->bi_private = state;
1913 bio->bi_end_io = failed_bio->bi_end_io;
1914 bio->bi_sector = failrec->logical >> 9;
1915 bio->bi_bdev = failed_bio->bi_bdev;
1918 bio_add_page(bio, page, failrec->len, start - page_offset(page));
1919 if (failed_bio->bi_rw & REQ_WRITE)
1924 ret = BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
1925 failrec->last_mirror,
1926 failrec->bio_flags, 0);
1931 * each time an IO finishes, we do a fast check in the IO failure tree
1932 * to see if we need to process or clean up an io_failure_record
1934 static int btrfs_clean_io_failures(struct inode *inode, u64 start)
1937 u64 private_failure;
1938 struct io_failure_record *failure;
1942 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1943 (u64)-1, 1, EXTENT_DIRTY, 0)) {
1944 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
1945 start, &private_failure);
1947 failure = (struct io_failure_record *)(unsigned long)
1949 set_state_private(&BTRFS_I(inode)->io_failure_tree,
1951 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
1953 failure->start + failure->len - 1,
1954 EXTENT_DIRTY | EXTENT_LOCKED,
1963 * when reads are done, we need to check csums to verify the data is correct
1964 * if there's a match, we allow the bio to finish. If not, we go through
1965 * the io_failure_record routines to find good copies
1967 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1968 struct extent_state *state)
1970 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1971 struct inode *inode = page->mapping->host;
1972 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1974 u64 private = ~(u32)0;
1976 struct btrfs_root *root = BTRFS_I(inode)->root;
1979 if (PageChecked(page)) {
1980 ClearPageChecked(page);
1984 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1987 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1988 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1989 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1994 if (state && state->start == start) {
1995 private = state->private;
1998 ret = get_state_private(io_tree, start, &private);
2000 kaddr = kmap_atomic(page, KM_USER0);
2004 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
2005 btrfs_csum_final(csum, (char *)&csum);
2006 if (csum != private)
2009 kunmap_atomic(kaddr, KM_USER0);
2011 /* if the io failure tree for this inode is non-empty,
2012 * check to see if we've recovered from a failed IO
2014 btrfs_clean_io_failures(inode, start);
2018 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
2020 (unsigned long long)btrfs_ino(page->mapping->host),
2021 (unsigned long long)start, csum,
2022 (unsigned long long)private);
2023 memset(kaddr + offset, 1, end - start + 1);
2024 flush_dcache_page(page);
2025 kunmap_atomic(kaddr, KM_USER0);
2031 struct delayed_iput {
2032 struct list_head list;
2033 struct inode *inode;
2036 void btrfs_add_delayed_iput(struct inode *inode)
2038 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2039 struct delayed_iput *delayed;
2041 if (atomic_add_unless(&inode->i_count, -1, 1))
2044 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2045 delayed->inode = inode;
2047 spin_lock(&fs_info->delayed_iput_lock);
2048 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2049 spin_unlock(&fs_info->delayed_iput_lock);
2052 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2055 struct btrfs_fs_info *fs_info = root->fs_info;
2056 struct delayed_iput *delayed;
2059 spin_lock(&fs_info->delayed_iput_lock);
2060 empty = list_empty(&fs_info->delayed_iputs);
2061 spin_unlock(&fs_info->delayed_iput_lock);
2065 down_read(&root->fs_info->cleanup_work_sem);
2066 spin_lock(&fs_info->delayed_iput_lock);
2067 list_splice_init(&fs_info->delayed_iputs, &list);
2068 spin_unlock(&fs_info->delayed_iput_lock);
2070 while (!list_empty(&list)) {
2071 delayed = list_entry(list.next, struct delayed_iput, list);
2072 list_del(&delayed->list);
2073 iput(delayed->inode);
2076 up_read(&root->fs_info->cleanup_work_sem);
2080 * calculate extra metadata reservation when snapshotting a subvolume
2081 * contains orphan files.
2083 void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans,
2084 struct btrfs_pending_snapshot *pending,
2085 u64 *bytes_to_reserve)
2087 struct btrfs_root *root;
2088 struct btrfs_block_rsv *block_rsv;
2092 root = pending->root;
2093 if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
2096 block_rsv = root->orphan_block_rsv;
2098 /* orphan block reservation for the snapshot */
2099 num_bytes = block_rsv->size;
2102 * after the snapshot is created, COWing tree blocks may use more
2103 * space than it frees. So we should make sure there is enough
2106 index = trans->transid & 0x1;
2107 if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
2108 num_bytes += block_rsv->size -
2109 (block_rsv->reserved + block_rsv->freed[index]);
2112 *bytes_to_reserve += num_bytes;
2115 void btrfs_orphan_post_snapshot(struct btrfs_trans_handle *trans,
2116 struct btrfs_pending_snapshot *pending)
2118 struct btrfs_root *root = pending->root;
2119 struct btrfs_root *snap = pending->snap;
2120 struct btrfs_block_rsv *block_rsv;
2125 if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
2128 /* refill source subvolume's orphan block reservation */
2129 block_rsv = root->orphan_block_rsv;
2130 index = trans->transid & 0x1;
2131 if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
2132 num_bytes = block_rsv->size -
2133 (block_rsv->reserved + block_rsv->freed[index]);
2134 ret = btrfs_block_rsv_migrate(&pending->block_rsv,
2135 root->orphan_block_rsv,
2140 /* setup orphan block reservation for the snapshot */
2141 block_rsv = btrfs_alloc_block_rsv(snap);
2144 btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
2145 snap->orphan_block_rsv = block_rsv;
2147 num_bytes = root->orphan_block_rsv->size;
2148 ret = btrfs_block_rsv_migrate(&pending->block_rsv,
2149 block_rsv, num_bytes);
2153 /* insert orphan item for the snapshot */
2154 WARN_ON(!root->orphan_item_inserted);
2155 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2156 snap->root_key.objectid);
2158 snap->orphan_item_inserted = 1;
2162 enum btrfs_orphan_cleanup_state {
2163 ORPHAN_CLEANUP_STARTED = 1,
2164 ORPHAN_CLEANUP_DONE = 2,
2168 * This is called in transaction commmit time. If there are no orphan
2169 * files in the subvolume, it removes orphan item and frees block_rsv
2172 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2173 struct btrfs_root *root)
2177 if (!list_empty(&root->orphan_list) ||
2178 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2181 if (root->orphan_item_inserted &&
2182 btrfs_root_refs(&root->root_item) > 0) {
2183 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2184 root->root_key.objectid);
2186 root->orphan_item_inserted = 0;
2189 if (root->orphan_block_rsv) {
2190 WARN_ON(root->orphan_block_rsv->size > 0);
2191 btrfs_free_block_rsv(root, root->orphan_block_rsv);
2192 root->orphan_block_rsv = NULL;
2197 * This creates an orphan entry for the given inode in case something goes
2198 * wrong in the middle of an unlink/truncate.
2200 * NOTE: caller of this function should reserve 5 units of metadata for
2203 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2205 struct btrfs_root *root = BTRFS_I(inode)->root;
2206 struct btrfs_block_rsv *block_rsv = NULL;
2211 if (!root->orphan_block_rsv) {
2212 block_rsv = btrfs_alloc_block_rsv(root);
2216 spin_lock(&root->orphan_lock);
2217 if (!root->orphan_block_rsv) {
2218 root->orphan_block_rsv = block_rsv;
2219 } else if (block_rsv) {
2220 btrfs_free_block_rsv(root, block_rsv);
2224 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2225 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2228 * For proper ENOSPC handling, we should do orphan
2229 * cleanup when mounting. But this introduces backward
2230 * compatibility issue.
2232 if (!xchg(&root->orphan_item_inserted, 1))
2240 if (!BTRFS_I(inode)->orphan_meta_reserved) {
2241 BTRFS_I(inode)->orphan_meta_reserved = 1;
2244 spin_unlock(&root->orphan_lock);
2247 btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
2249 /* grab metadata reservation from transaction handle */
2251 ret = btrfs_orphan_reserve_metadata(trans, inode);
2255 /* insert an orphan item to track this unlinked/truncated file */
2257 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2261 /* insert an orphan item to track subvolume contains orphan files */
2263 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2264 root->root_key.objectid);
2271 * We have done the truncate/delete so we can go ahead and remove the orphan
2272 * item for this particular inode.
2274 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2276 struct btrfs_root *root = BTRFS_I(inode)->root;
2277 int delete_item = 0;
2278 int release_rsv = 0;
2281 spin_lock(&root->orphan_lock);
2282 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2283 list_del_init(&BTRFS_I(inode)->i_orphan);
2287 if (BTRFS_I(inode)->orphan_meta_reserved) {
2288 BTRFS_I(inode)->orphan_meta_reserved = 0;
2291 spin_unlock(&root->orphan_lock);
2293 if (trans && delete_item) {
2294 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
2299 btrfs_orphan_release_metadata(inode);
2305 * this cleans up any orphans that may be left on the list from the last use
2308 int btrfs_orphan_cleanup(struct btrfs_root *root)
2310 struct btrfs_path *path;
2311 struct extent_buffer *leaf;
2312 struct btrfs_key key, found_key;
2313 struct btrfs_trans_handle *trans;
2314 struct inode *inode;
2315 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2317 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
2320 path = btrfs_alloc_path();
2327 key.objectid = BTRFS_ORPHAN_OBJECTID;
2328 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2329 key.offset = (u64)-1;
2332 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2337 * if ret == 0 means we found what we were searching for, which
2338 * is weird, but possible, so only screw with path if we didn't
2339 * find the key and see if we have stuff that matches
2343 if (path->slots[0] == 0)
2348 /* pull out the item */
2349 leaf = path->nodes[0];
2350 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2352 /* make sure the item matches what we want */
2353 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2355 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2358 /* release the path since we're done with it */
2359 btrfs_release_path(path);
2362 * this is where we are basically btrfs_lookup, without the
2363 * crossing root thing. we store the inode number in the
2364 * offset of the orphan item.
2366 found_key.objectid = found_key.offset;
2367 found_key.type = BTRFS_INODE_ITEM_KEY;
2368 found_key.offset = 0;
2369 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2370 if (IS_ERR(inode)) {
2371 ret = PTR_ERR(inode);
2376 * add this inode to the orphan list so btrfs_orphan_del does
2377 * the proper thing when we hit it
2379 spin_lock(&root->orphan_lock);
2380 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2381 spin_unlock(&root->orphan_lock);
2384 * if this is a bad inode, means we actually succeeded in
2385 * removing the inode, but not the orphan record, which means
2386 * we need to manually delete the orphan since iput will just
2387 * do a destroy_inode
2389 if (is_bad_inode(inode)) {
2390 trans = btrfs_start_transaction(root, 0);
2391 if (IS_ERR(trans)) {
2392 ret = PTR_ERR(trans);
2395 btrfs_orphan_del(trans, inode);
2396 btrfs_end_transaction(trans, root);
2401 /* if we have links, this was a truncate, lets do that */
2402 if (inode->i_nlink) {
2403 if (!S_ISREG(inode->i_mode)) {
2409 ret = btrfs_truncate(inode);
2414 /* this will do delete_inode and everything for us */
2419 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
2421 if (root->orphan_block_rsv)
2422 btrfs_block_rsv_release(root, root->orphan_block_rsv,
2425 if (root->orphan_block_rsv || root->orphan_item_inserted) {
2426 trans = btrfs_join_transaction(root, 1);
2428 btrfs_end_transaction(trans, root);
2432 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2434 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2438 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
2439 btrfs_free_path(path);
2444 * very simple check to peek ahead in the leaf looking for xattrs. If we
2445 * don't find any xattrs, we know there can't be any acls.
2447 * slot is the slot the inode is in, objectid is the objectid of the inode
2449 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2450 int slot, u64 objectid)
2452 u32 nritems = btrfs_header_nritems(leaf);
2453 struct btrfs_key found_key;
2457 while (slot < nritems) {
2458 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2460 /* we found a different objectid, there must not be acls */
2461 if (found_key.objectid != objectid)
2464 /* we found an xattr, assume we've got an acl */
2465 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2469 * we found a key greater than an xattr key, there can't
2470 * be any acls later on
2472 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2479 * it goes inode, inode backrefs, xattrs, extents,
2480 * so if there are a ton of hard links to an inode there can
2481 * be a lot of backrefs. Don't waste time searching too hard,
2482 * this is just an optimization
2487 /* we hit the end of the leaf before we found an xattr or
2488 * something larger than an xattr. We have to assume the inode
2495 * read an inode from the btree into the in-memory inode
2497 static void btrfs_read_locked_inode(struct inode *inode)
2499 struct btrfs_path *path;
2500 struct extent_buffer *leaf;
2501 struct btrfs_inode_item *inode_item;
2502 struct btrfs_timespec *tspec;
2503 struct btrfs_root *root = BTRFS_I(inode)->root;
2504 struct btrfs_key location;
2506 u64 alloc_group_block;
2510 path = btrfs_alloc_path();
2512 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2514 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2518 leaf = path->nodes[0];
2519 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2520 struct btrfs_inode_item);
2522 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2523 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
2524 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2525 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2526 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2528 tspec = btrfs_inode_atime(inode_item);
2529 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2530 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2532 tspec = btrfs_inode_mtime(inode_item);
2533 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2534 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2536 tspec = btrfs_inode_ctime(inode_item);
2537 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2538 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2540 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2541 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2542 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2543 inode->i_generation = BTRFS_I(inode)->generation;
2545 rdev = btrfs_inode_rdev(leaf, inode_item);
2547 BTRFS_I(inode)->index_cnt = (u64)-1;
2548 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2550 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
2553 * try to precache a NULL acl entry for files that don't have
2554 * any xattrs or acls
2556 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
2559 cache_no_acl(inode);
2561 BTRFS_I(inode)->block_group = btrfs_find_block_group(root, 0,
2562 alloc_group_block, 0);
2563 btrfs_free_path(path);
2566 switch (inode->i_mode & S_IFMT) {
2568 inode->i_mapping->a_ops = &btrfs_aops;
2569 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2570 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2571 inode->i_fop = &btrfs_file_operations;
2572 inode->i_op = &btrfs_file_inode_operations;
2575 inode->i_fop = &btrfs_dir_file_operations;
2576 if (root == root->fs_info->tree_root)
2577 inode->i_op = &btrfs_dir_ro_inode_operations;
2579 inode->i_op = &btrfs_dir_inode_operations;
2582 inode->i_op = &btrfs_symlink_inode_operations;
2583 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2584 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2587 inode->i_op = &btrfs_special_inode_operations;
2588 init_special_inode(inode, inode->i_mode, rdev);
2592 btrfs_update_iflags(inode);
2596 btrfs_free_path(path);
2597 make_bad_inode(inode);
2601 * given a leaf and an inode, copy the inode fields into the leaf
2603 static void fill_inode_item(struct btrfs_trans_handle *trans,
2604 struct extent_buffer *leaf,
2605 struct btrfs_inode_item *item,
2606 struct inode *inode)
2608 if (!leaf->map_token)
2609 map_private_extent_buffer(leaf, (unsigned long)item,
2610 sizeof(struct btrfs_inode_item),
2611 &leaf->map_token, &leaf->kaddr,
2612 &leaf->map_start, &leaf->map_len,
2615 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2616 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2617 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2618 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2619 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2621 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2622 inode->i_atime.tv_sec);
2623 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2624 inode->i_atime.tv_nsec);
2626 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2627 inode->i_mtime.tv_sec);
2628 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2629 inode->i_mtime.tv_nsec);
2631 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2632 inode->i_ctime.tv_sec);
2633 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2634 inode->i_ctime.tv_nsec);
2636 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2637 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2638 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2639 btrfs_set_inode_transid(leaf, item, trans->transid);
2640 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2641 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2642 btrfs_set_inode_block_group(leaf, item, BTRFS_I(inode)->block_group);
2644 if (leaf->map_token) {
2645 unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
2646 leaf->map_token = NULL;
2651 * copy everything in the in-memory inode into the btree.
2653 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2654 struct btrfs_root *root, struct inode *inode)
2656 struct btrfs_inode_item *inode_item;
2657 struct btrfs_path *path;
2658 struct extent_buffer *leaf;
2662 * If root is tree root, it means this inode is used to
2663 * store free space information. And these inodes are updated
2664 * when committing the transaction, so they needn't delaye to
2665 * be updated, or deadlock will occured.
2667 if (!is_free_space_inode(root, inode)) {
2668 ret = btrfs_delayed_update_inode(trans, root, inode);
2670 btrfs_set_inode_last_trans(trans, inode);
2674 path = btrfs_alloc_path();
2678 path->leave_spinning = 1;
2679 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
2687 btrfs_unlock_up_safe(path, 1);
2688 leaf = path->nodes[0];
2689 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2690 struct btrfs_inode_item);
2692 fill_inode_item(trans, leaf, inode_item, inode);
2693 btrfs_mark_buffer_dirty(leaf);
2694 btrfs_set_inode_last_trans(trans, inode);
2697 btrfs_free_path(path);
2702 * unlink helper that gets used here in inode.c and in the tree logging
2703 * recovery code. It remove a link in a directory with a given name, and
2704 * also drops the back refs in the inode to the directory
2706 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2707 struct btrfs_root *root,
2708 struct inode *dir, struct inode *inode,
2709 const char *name, int name_len)
2711 struct btrfs_path *path;
2713 struct extent_buffer *leaf;
2714 struct btrfs_dir_item *di;
2715 struct btrfs_key key;
2717 u64 ino = btrfs_ino(inode);
2718 u64 dir_ino = btrfs_ino(dir);
2720 path = btrfs_alloc_path();
2726 path->leave_spinning = 1;
2727 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2728 name, name_len, -1);
2737 leaf = path->nodes[0];
2738 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2739 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2742 btrfs_release_path(path);
2744 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
2747 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2748 "inode %llu parent %llu\n", name_len, name,
2749 (unsigned long long)ino, (unsigned long long)dir_ino);
2753 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2757 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2759 BUG_ON(ret != 0 && ret != -ENOENT);
2761 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2766 btrfs_free_path(path);
2770 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2771 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2772 btrfs_update_inode(trans, root, dir);
2777 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2778 struct btrfs_root *root,
2779 struct inode *dir, struct inode *inode,
2780 const char *name, int name_len)
2783 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
2785 btrfs_drop_nlink(inode);
2786 ret = btrfs_update_inode(trans, root, inode);
2792 /* helper to check if there is any shared block in the path */
2793 static int check_path_shared(struct btrfs_root *root,
2794 struct btrfs_path *path)
2796 struct extent_buffer *eb;
2800 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2803 if (!path->nodes[level])
2805 eb = path->nodes[level];
2806 if (!btrfs_block_can_be_shared(root, eb))
2808 ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len,
2817 * helper to start transaction for unlink and rmdir.
2819 * unlink and rmdir are special in btrfs, they do not always free space.
2820 * so in enospc case, we should make sure they will free space before
2821 * allowing them to use the global metadata reservation.
2823 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
2824 struct dentry *dentry)
2826 struct btrfs_trans_handle *trans;
2827 struct btrfs_root *root = BTRFS_I(dir)->root;
2828 struct btrfs_path *path;
2829 struct btrfs_inode_ref *ref;
2830 struct btrfs_dir_item *di;
2831 struct inode *inode = dentry->d_inode;
2836 u64 ino = btrfs_ino(inode);
2837 u64 dir_ino = btrfs_ino(dir);
2839 trans = btrfs_start_transaction(root, 10);
2840 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
2843 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
2844 return ERR_PTR(-ENOSPC);
2846 /* check if there is someone else holds reference */
2847 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
2848 return ERR_PTR(-ENOSPC);
2850 if (atomic_read(&inode->i_count) > 2)
2851 return ERR_PTR(-ENOSPC);
2853 if (xchg(&root->fs_info->enospc_unlink, 1))
2854 return ERR_PTR(-ENOSPC);
2856 path = btrfs_alloc_path();
2858 root->fs_info->enospc_unlink = 0;
2859 return ERR_PTR(-ENOMEM);
2862 trans = btrfs_start_transaction(root, 0);
2863 if (IS_ERR(trans)) {
2864 btrfs_free_path(path);
2865 root->fs_info->enospc_unlink = 0;
2869 path->skip_locking = 1;
2870 path->search_commit_root = 1;
2872 ret = btrfs_lookup_inode(trans, root, path,
2873 &BTRFS_I(dir)->location, 0);
2879 if (check_path_shared(root, path))
2884 btrfs_release_path(path);
2886 ret = btrfs_lookup_inode(trans, root, path,
2887 &BTRFS_I(inode)->location, 0);
2893 if (check_path_shared(root, path))
2898 btrfs_release_path(path);
2900 if (ret == 0 && S_ISREG(inode->i_mode)) {
2901 ret = btrfs_lookup_file_extent(trans, root, path,
2908 if (check_path_shared(root, path))
2910 btrfs_release_path(path);
2918 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2919 dentry->d_name.name, dentry->d_name.len, 0);
2925 if (check_path_shared(root, path))
2931 btrfs_release_path(path);
2933 ref = btrfs_lookup_inode_ref(trans, root, path,
2934 dentry->d_name.name, dentry->d_name.len,
2941 if (check_path_shared(root, path))
2943 index = btrfs_inode_ref_index(path->nodes[0], ref);
2944 btrfs_release_path(path);
2947 * This is a commit root search, if we can lookup inode item and other
2948 * relative items in the commit root, it means the transaction of
2949 * dir/file creation has been committed, and the dir index item that we
2950 * delay to insert has also been inserted into the commit root. So
2951 * we needn't worry about the delayed insertion of the dir index item
2954 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
2955 dentry->d_name.name, dentry->d_name.len, 0);
2960 BUG_ON(ret == -ENOENT);
2961 if (check_path_shared(root, path))
2966 btrfs_free_path(path);
2968 btrfs_end_transaction(trans, root);
2969 root->fs_info->enospc_unlink = 0;
2970 return ERR_PTR(err);
2973 trans->block_rsv = &root->fs_info->global_block_rsv;
2977 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
2978 struct btrfs_root *root)
2980 if (trans->block_rsv == &root->fs_info->global_block_rsv) {
2981 BUG_ON(!root->fs_info->enospc_unlink);
2982 root->fs_info->enospc_unlink = 0;
2984 btrfs_end_transaction_throttle(trans, root);
2987 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2989 struct btrfs_root *root = BTRFS_I(dir)->root;
2990 struct btrfs_trans_handle *trans;
2991 struct inode *inode = dentry->d_inode;
2993 unsigned long nr = 0;
2995 trans = __unlink_start_trans(dir, dentry);
2997 return PTR_ERR(trans);
2999 btrfs_set_trans_block_group(trans, dir);
3001 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3003 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3004 dentry->d_name.name, dentry->d_name.len);
3007 if (inode->i_nlink == 0) {
3008 ret = btrfs_orphan_add(trans, inode);
3012 nr = trans->blocks_used;
3013 __unlink_end_trans(trans, root);
3014 btrfs_btree_balance_dirty(root, nr);
3018 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3019 struct btrfs_root *root,
3020 struct inode *dir, u64 objectid,
3021 const char *name, int name_len)
3023 struct btrfs_path *path;
3024 struct extent_buffer *leaf;
3025 struct btrfs_dir_item *di;
3026 struct btrfs_key key;
3029 u64 dir_ino = btrfs_ino(dir);
3031 path = btrfs_alloc_path();
3035 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3036 name, name_len, -1);
3037 BUG_ON(IS_ERR_OR_NULL(di));
3039 leaf = path->nodes[0];
3040 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3041 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3042 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3044 btrfs_release_path(path);
3046 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3047 objectid, root->root_key.objectid,
3048 dir_ino, &index, name, name_len);
3050 BUG_ON(ret != -ENOENT);
3051 di = btrfs_search_dir_index_item(root, path, dir_ino,
3053 BUG_ON(IS_ERR_OR_NULL(di));
3055 leaf = path->nodes[0];
3056 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3057 btrfs_release_path(path);
3060 btrfs_release_path(path);
3062 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3065 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3066 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3067 ret = btrfs_update_inode(trans, root, dir);
3073 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3075 struct inode *inode = dentry->d_inode;
3077 struct btrfs_root *root = BTRFS_I(dir)->root;
3078 struct btrfs_trans_handle *trans;
3079 unsigned long nr = 0;
3081 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
3082 btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3085 trans = __unlink_start_trans(dir, dentry);
3087 return PTR_ERR(trans);
3089 btrfs_set_trans_block_group(trans, dir);
3091 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3092 err = btrfs_unlink_subvol(trans, root, dir,
3093 BTRFS_I(inode)->location.objectid,
3094 dentry->d_name.name,
3095 dentry->d_name.len);
3099 err = btrfs_orphan_add(trans, inode);
3103 /* now the directory is empty */
3104 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3105 dentry->d_name.name, dentry->d_name.len);
3107 btrfs_i_size_write(inode, 0);
3109 nr = trans->blocks_used;
3110 __unlink_end_trans(trans, root);
3111 btrfs_btree_balance_dirty(root, nr);
3117 * this can truncate away extent items, csum items and directory items.
3118 * It starts at a high offset and removes keys until it can't find
3119 * any higher than new_size
3121 * csum items that cross the new i_size are truncated to the new size
3124 * min_type is the minimum key type to truncate down to. If set to 0, this
3125 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3127 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3128 struct btrfs_root *root,
3129 struct inode *inode,
3130 u64 new_size, u32 min_type)
3132 struct btrfs_path *path;
3133 struct extent_buffer *leaf;
3134 struct btrfs_file_extent_item *fi;
3135 struct btrfs_key key;
3136 struct btrfs_key found_key;
3137 u64 extent_start = 0;
3138 u64 extent_num_bytes = 0;
3139 u64 extent_offset = 0;
3141 u64 mask = root->sectorsize - 1;
3142 u32 found_type = (u8)-1;
3145 int pending_del_nr = 0;
3146 int pending_del_slot = 0;
3147 int extent_type = -1;
3151 u64 ino = btrfs_ino(inode);
3153 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3155 if (root->ref_cows || root == root->fs_info->tree_root)
3156 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
3159 * This function is also used to drop the items in the log tree before
3160 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3161 * it is used to drop the loged items. So we shouldn't kill the delayed
3164 if (min_type == 0 && root == BTRFS_I(inode)->root)
3165 btrfs_kill_delayed_inode_items(inode);
3167 path = btrfs_alloc_path();
3172 key.offset = (u64)-1;
3176 path->leave_spinning = 1;
3177 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3184 /* there are no items in the tree for us to truncate, we're
3187 if (path->slots[0] == 0)
3194 leaf = path->nodes[0];
3195 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3196 found_type = btrfs_key_type(&found_key);
3199 if (found_key.objectid != ino)
3202 if (found_type < min_type)
3205 item_end = found_key.offset;
3206 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3207 fi = btrfs_item_ptr(leaf, path->slots[0],
3208 struct btrfs_file_extent_item);
3209 extent_type = btrfs_file_extent_type(leaf, fi);
3210 encoding = btrfs_file_extent_compression(leaf, fi);
3211 encoding |= btrfs_file_extent_encryption(leaf, fi);
3212 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
3214 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3216 btrfs_file_extent_num_bytes(leaf, fi);
3217 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3218 item_end += btrfs_file_extent_inline_len(leaf,
3223 if (found_type > min_type) {
3226 if (item_end < new_size)
3228 if (found_key.offset >= new_size)
3234 /* FIXME, shrink the extent if the ref count is only 1 */
3235 if (found_type != BTRFS_EXTENT_DATA_KEY)
3238 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3240 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3241 if (!del_item && !encoding) {
3242 u64 orig_num_bytes =
3243 btrfs_file_extent_num_bytes(leaf, fi);
3244 extent_num_bytes = new_size -
3245 found_key.offset + root->sectorsize - 1;
3246 extent_num_bytes = extent_num_bytes &
3247 ~((u64)root->sectorsize - 1);
3248 btrfs_set_file_extent_num_bytes(leaf, fi,
3250 num_dec = (orig_num_bytes -
3252 if (root->ref_cows && extent_start != 0)
3253 inode_sub_bytes(inode, num_dec);
3254 btrfs_mark_buffer_dirty(leaf);
3257 btrfs_file_extent_disk_num_bytes(leaf,
3259 extent_offset = found_key.offset -
3260 btrfs_file_extent_offset(leaf, fi);
3262 /* FIXME blocksize != 4096 */
3263 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
3264 if (extent_start != 0) {
3267 inode_sub_bytes(inode, num_dec);
3270 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3272 * we can't truncate inline items that have had
3276 btrfs_file_extent_compression(leaf, fi) == 0 &&
3277 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3278 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3279 u32 size = new_size - found_key.offset;
3281 if (root->ref_cows) {
3282 inode_sub_bytes(inode, item_end + 1 -
3286 btrfs_file_extent_calc_inline_size(size);
3287 ret = btrfs_truncate_item(trans, root, path,
3290 } else if (root->ref_cows) {
3291 inode_sub_bytes(inode, item_end + 1 -
3297 if (!pending_del_nr) {
3298 /* no pending yet, add ourselves */
3299 pending_del_slot = path->slots[0];
3301 } else if (pending_del_nr &&
3302 path->slots[0] + 1 == pending_del_slot) {
3303 /* hop on the pending chunk */
3305 pending_del_slot = path->slots[0];
3312 if (found_extent && (root->ref_cows ||
3313 root == root->fs_info->tree_root)) {
3314 btrfs_set_path_blocking(path);
3315 ret = btrfs_free_extent(trans, root, extent_start,
3316 extent_num_bytes, 0,
3317 btrfs_header_owner(leaf),
3318 ino, extent_offset);
3322 if (found_type == BTRFS_INODE_ITEM_KEY)
3325 if (path->slots[0] == 0 ||
3326 path->slots[0] != pending_del_slot) {
3327 if (root->ref_cows &&
3328 BTRFS_I(inode)->location.objectid !=
3329 BTRFS_FREE_INO_OBJECTID) {
3333 if (pending_del_nr) {
3334 ret = btrfs_del_items(trans, root, path,
3340 btrfs_release_path(path);
3347 if (pending_del_nr) {
3348 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3352 btrfs_free_path(path);
3357 * taken from block_truncate_page, but does cow as it zeros out
3358 * any bytes left in the last page in the file.
3360 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3362 struct inode *inode = mapping->host;
3363 struct btrfs_root *root = BTRFS_I(inode)->root;
3364 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3365 struct btrfs_ordered_extent *ordered;
3366 struct extent_state *cached_state = NULL;
3368 u32 blocksize = root->sectorsize;
3369 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3370 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3376 if ((offset & (blocksize - 1)) == 0)
3378 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
3384 page = grab_cache_page(mapping, index);
3386 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3390 page_start = page_offset(page);
3391 page_end = page_start + PAGE_CACHE_SIZE - 1;
3393 if (!PageUptodate(page)) {
3394 ret = btrfs_readpage(NULL, page);
3396 if (page->mapping != mapping) {
3398 page_cache_release(page);
3401 if (!PageUptodate(page)) {
3406 wait_on_page_writeback(page);
3408 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
3410 set_page_extent_mapped(page);
3412 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3414 unlock_extent_cached(io_tree, page_start, page_end,
3415 &cached_state, GFP_NOFS);
3417 page_cache_release(page);
3418 btrfs_start_ordered_extent(inode, ordered, 1);
3419 btrfs_put_ordered_extent(ordered);
3423 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
3424 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3425 0, 0, &cached_state, GFP_NOFS);
3427 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
3430 unlock_extent_cached(io_tree, page_start, page_end,
3431 &cached_state, GFP_NOFS);
3436 if (offset != PAGE_CACHE_SIZE) {
3438 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3439 flush_dcache_page(page);
3442 ClearPageChecked(page);
3443 set_page_dirty(page);
3444 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
3449 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3451 page_cache_release(page);
3457 * This function puts in dummy file extents for the area we're creating a hole
3458 * for. So if we are truncating this file to a larger size we need to insert
3459 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
3460 * the range between oldsize and size
3462 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
3464 struct btrfs_trans_handle *trans;
3465 struct btrfs_root *root = BTRFS_I(inode)->root;
3466 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3467 struct extent_map *em = NULL;
3468 struct extent_state *cached_state = NULL;
3469 u64 mask = root->sectorsize - 1;
3470 u64 hole_start = (oldsize + mask) & ~mask;
3471 u64 block_end = (size + mask) & ~mask;
3477 if (size <= hole_start)
3481 struct btrfs_ordered_extent *ordered;
3482 btrfs_wait_ordered_range(inode, hole_start,
3483 block_end - hole_start);
3484 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
3485 &cached_state, GFP_NOFS);
3486 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3489 unlock_extent_cached(io_tree, hole_start, block_end - 1,
3490 &cached_state, GFP_NOFS);
3491 btrfs_put_ordered_extent(ordered);
3494 cur_offset = hole_start;
3496 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3497 block_end - cur_offset, 0);
3498 BUG_ON(IS_ERR_OR_NULL(em));
3499 last_byte = min(extent_map_end(em), block_end);
3500 last_byte = (last_byte + mask) & ~mask;
3501 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3503 hole_size = last_byte - cur_offset;
3505 trans = btrfs_start_transaction(root, 2);
3506 if (IS_ERR(trans)) {
3507 err = PTR_ERR(trans);
3510 btrfs_set_trans_block_group(trans, inode);
3512 err = btrfs_drop_extents(trans, inode, cur_offset,
3513 cur_offset + hole_size,
3518 err = btrfs_insert_file_extent(trans, root,
3519 btrfs_ino(inode), cur_offset, 0,
3520 0, hole_size, 0, hole_size,
3525 btrfs_drop_extent_cache(inode, hole_start,
3528 btrfs_end_transaction(trans, root);
3530 free_extent_map(em);
3532 cur_offset = last_byte;
3533 if (cur_offset >= block_end)
3537 free_extent_map(em);
3538 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
3543 static int btrfs_setsize(struct inode *inode, loff_t newsize)
3545 loff_t oldsize = i_size_read(inode);
3548 if (newsize == oldsize)
3551 if (newsize > oldsize) {
3552 i_size_write(inode, newsize);
3553 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
3554 truncate_pagecache(inode, oldsize, newsize);
3555 ret = btrfs_cont_expand(inode, oldsize, newsize);
3557 btrfs_setsize(inode, oldsize);
3561 mark_inode_dirty(inode);
3565 * We're truncating a file that used to have good data down to
3566 * zero. Make sure it gets into the ordered flush list so that
3567 * any new writes get down to disk quickly.
3570 BTRFS_I(inode)->ordered_data_close = 1;
3572 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3573 truncate_setsize(inode, newsize);
3574 ret = btrfs_truncate(inode);
3580 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3582 struct inode *inode = dentry->d_inode;
3583 struct btrfs_root *root = BTRFS_I(inode)->root;
3586 if (btrfs_root_readonly(root))
3589 err = inode_change_ok(inode, attr);
3593 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3594 err = btrfs_setsize(inode, attr->ia_size);
3599 if (attr->ia_valid) {
3600 setattr_copy(inode, attr);
3601 mark_inode_dirty(inode);
3603 if (attr->ia_valid & ATTR_MODE)
3604 err = btrfs_acl_chmod(inode);
3610 void btrfs_evict_inode(struct inode *inode)
3612 struct btrfs_trans_handle *trans;
3613 struct btrfs_root *root = BTRFS_I(inode)->root;
3617 trace_btrfs_inode_evict(inode);
3619 truncate_inode_pages(&inode->i_data, 0);
3620 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
3621 is_free_space_inode(root, inode)))
3624 if (is_bad_inode(inode)) {
3625 btrfs_orphan_del(NULL, inode);
3628 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
3629 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3631 if (root->fs_info->log_root_recovering) {
3632 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3636 if (inode->i_nlink > 0) {
3637 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3641 btrfs_i_size_write(inode, 0);
3644 trans = btrfs_start_transaction(root, 0);
3645 BUG_ON(IS_ERR(trans));
3646 btrfs_set_trans_block_group(trans, inode);
3647 trans->block_rsv = root->orphan_block_rsv;
3649 ret = btrfs_block_rsv_check(trans, root,
3650 root->orphan_block_rsv, 0, 5);
3652 BUG_ON(ret != -EAGAIN);
3653 ret = btrfs_commit_transaction(trans, root);
3658 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3662 nr = trans->blocks_used;
3663 btrfs_end_transaction(trans, root);
3665 btrfs_btree_balance_dirty(root, nr);
3670 ret = btrfs_orphan_del(trans, inode);
3674 if (!(root == root->fs_info->tree_root ||
3675 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
3676 btrfs_return_ino(root, btrfs_ino(inode));
3678 nr = trans->blocks_used;
3679 btrfs_end_transaction(trans, root);
3680 btrfs_btree_balance_dirty(root, nr);
3682 end_writeback(inode);
3687 * this returns the key found in the dir entry in the location pointer.
3688 * If no dir entries were found, location->objectid is 0.
3690 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3691 struct btrfs_key *location)
3693 const char *name = dentry->d_name.name;
3694 int namelen = dentry->d_name.len;
3695 struct btrfs_dir_item *di;
3696 struct btrfs_path *path;
3697 struct btrfs_root *root = BTRFS_I(dir)->root;
3700 path = btrfs_alloc_path();
3703 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
3708 if (IS_ERR_OR_NULL(di))
3711 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3713 btrfs_free_path(path);
3716 location->objectid = 0;
3721 * when we hit a tree root in a directory, the btrfs part of the inode
3722 * needs to be changed to reflect the root directory of the tree root. This
3723 * is kind of like crossing a mount point.
3725 static int fixup_tree_root_location(struct btrfs_root *root,
3727 struct dentry *dentry,
3728 struct btrfs_key *location,
3729 struct btrfs_root **sub_root)
3731 struct btrfs_path *path;
3732 struct btrfs_root *new_root;
3733 struct btrfs_root_ref *ref;
3734 struct extent_buffer *leaf;
3738 path = btrfs_alloc_path();
3745 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3746 BTRFS_I(dir)->root->root_key.objectid,
3747 location->objectid);
3754 leaf = path->nodes[0];
3755 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3756 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
3757 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3760 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3761 (unsigned long)(ref + 1),
3762 dentry->d_name.len);
3766 btrfs_release_path(path);
3768 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3769 if (IS_ERR(new_root)) {
3770 err = PTR_ERR(new_root);
3774 if (btrfs_root_refs(&new_root->root_item) == 0) {
3779 *sub_root = new_root;
3780 location->objectid = btrfs_root_dirid(&new_root->root_item);
3781 location->type = BTRFS_INODE_ITEM_KEY;
3782 location->offset = 0;
3785 btrfs_free_path(path);
3789 static void inode_tree_add(struct inode *inode)
3791 struct btrfs_root *root = BTRFS_I(inode)->root;
3792 struct btrfs_inode *entry;
3794 struct rb_node *parent;
3795 u64 ino = btrfs_ino(inode);
3797 p = &root->inode_tree.rb_node;
3800 if (inode_unhashed(inode))
3803 spin_lock(&root->inode_lock);
3806 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3808 if (ino < btrfs_ino(&entry->vfs_inode))
3809 p = &parent->rb_left;
3810 else if (ino > btrfs_ino(&entry->vfs_inode))
3811 p = &parent->rb_right;
3813 WARN_ON(!(entry->vfs_inode.i_state &
3814 (I_WILL_FREE | I_FREEING)));
3815 rb_erase(parent, &root->inode_tree);
3816 RB_CLEAR_NODE(parent);
3817 spin_unlock(&root->inode_lock);
3821 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3822 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3823 spin_unlock(&root->inode_lock);
3826 static void inode_tree_del(struct inode *inode)
3828 struct btrfs_root *root = BTRFS_I(inode)->root;
3831 spin_lock(&root->inode_lock);
3832 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3833 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3834 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3835 empty = RB_EMPTY_ROOT(&root->inode_tree);
3837 spin_unlock(&root->inode_lock);
3840 * Free space cache has inodes in the tree root, but the tree root has a
3841 * root_refs of 0, so this could end up dropping the tree root as a
3842 * snapshot, so we need the extra !root->fs_info->tree_root check to
3843 * make sure we don't drop it.
3845 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
3846 root != root->fs_info->tree_root) {
3847 synchronize_srcu(&root->fs_info->subvol_srcu);
3848 spin_lock(&root->inode_lock);
3849 empty = RB_EMPTY_ROOT(&root->inode_tree);
3850 spin_unlock(&root->inode_lock);
3852 btrfs_add_dead_root(root);
3856 int btrfs_invalidate_inodes(struct btrfs_root *root)
3858 struct rb_node *node;
3859 struct rb_node *prev;
3860 struct btrfs_inode *entry;
3861 struct inode *inode;
3864 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3866 spin_lock(&root->inode_lock);
3868 node = root->inode_tree.rb_node;
3872 entry = rb_entry(node, struct btrfs_inode, rb_node);
3874 if (objectid < btrfs_ino(&entry->vfs_inode))
3875 node = node->rb_left;
3876 else if (objectid > btrfs_ino(&entry->vfs_inode))
3877 node = node->rb_right;
3883 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3884 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
3888 prev = rb_next(prev);
3892 entry = rb_entry(node, struct btrfs_inode, rb_node);
3893 objectid = btrfs_ino(&entry->vfs_inode) + 1;
3894 inode = igrab(&entry->vfs_inode);
3896 spin_unlock(&root->inode_lock);
3897 if (atomic_read(&inode->i_count) > 1)
3898 d_prune_aliases(inode);
3900 * btrfs_drop_inode will have it removed from
3901 * the inode cache when its usage count
3906 spin_lock(&root->inode_lock);
3910 if (cond_resched_lock(&root->inode_lock))
3913 node = rb_next(node);
3915 spin_unlock(&root->inode_lock);
3919 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3921 struct btrfs_iget_args *args = p;
3922 inode->i_ino = args->ino;
3923 BTRFS_I(inode)->root = args->root;
3924 btrfs_set_inode_space_info(args->root, inode);
3928 static int btrfs_find_actor(struct inode *inode, void *opaque)
3930 struct btrfs_iget_args *args = opaque;
3931 return args->ino == btrfs_ino(inode) &&
3932 args->root == BTRFS_I(inode)->root;
3935 static struct inode *btrfs_iget_locked(struct super_block *s,
3937 struct btrfs_root *root)
3939 struct inode *inode;
3940 struct btrfs_iget_args args;
3941 args.ino = objectid;
3944 inode = iget5_locked(s, objectid, btrfs_find_actor,
3945 btrfs_init_locked_inode,
3950 /* Get an inode object given its location and corresponding root.
3951 * Returns in *is_new if the inode was read from disk
3953 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3954 struct btrfs_root *root, int *new)
3956 struct inode *inode;
3958 inode = btrfs_iget_locked(s, location->objectid, root);
3960 return ERR_PTR(-ENOMEM);
3962 if (inode->i_state & I_NEW) {
3963 BTRFS_I(inode)->root = root;
3964 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3965 btrfs_read_locked_inode(inode);
3966 inode_tree_add(inode);
3967 unlock_new_inode(inode);
3975 static struct inode *new_simple_dir(struct super_block *s,
3976 struct btrfs_key *key,
3977 struct btrfs_root *root)
3979 struct inode *inode = new_inode(s);
3982 return ERR_PTR(-ENOMEM);
3984 BTRFS_I(inode)->root = root;
3985 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3986 BTRFS_I(inode)->dummy_inode = 1;
3988 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
3989 inode->i_op = &simple_dir_inode_operations;
3990 inode->i_fop = &simple_dir_operations;
3991 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
3992 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3997 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3999 struct inode *inode;
4000 struct btrfs_root *root = BTRFS_I(dir)->root;
4001 struct btrfs_root *sub_root = root;
4002 struct btrfs_key location;
4006 if (dentry->d_name.len > BTRFS_NAME_LEN)
4007 return ERR_PTR(-ENAMETOOLONG);
4009 ret = btrfs_inode_by_name(dir, dentry, &location);
4012 return ERR_PTR(ret);
4014 if (location.objectid == 0)
4017 if (location.type == BTRFS_INODE_ITEM_KEY) {
4018 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
4022 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
4024 index = srcu_read_lock(&root->fs_info->subvol_srcu);
4025 ret = fixup_tree_root_location(root, dir, dentry,
4026 &location, &sub_root);
4029 inode = ERR_PTR(ret);
4031 inode = new_simple_dir(dir->i_sb, &location, sub_root);
4033 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
4035 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
4037 if (!IS_ERR(inode) && root != sub_root) {
4038 down_read(&root->fs_info->cleanup_work_sem);
4039 if (!(inode->i_sb->s_flags & MS_RDONLY))
4040 ret = btrfs_orphan_cleanup(sub_root);
4041 up_read(&root->fs_info->cleanup_work_sem);
4043 inode = ERR_PTR(ret);
4049 static int btrfs_dentry_delete(const struct dentry *dentry)
4051 struct btrfs_root *root;
4053 if (!dentry->d_inode && !IS_ROOT(dentry))
4054 dentry = dentry->d_parent;
4056 if (dentry->d_inode) {
4057 root = BTRFS_I(dentry->d_inode)->root;
4058 if (btrfs_root_refs(&root->root_item) == 0)
4064 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
4065 struct nameidata *nd)
4067 struct inode *inode;
4069 inode = btrfs_lookup_dentry(dir, dentry);
4071 return ERR_CAST(inode);
4073 return d_splice_alias(inode, dentry);
4076 unsigned char btrfs_filetype_table[] = {
4077 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
4080 static int btrfs_real_readdir(struct file *filp, void *dirent,
4083 struct inode *inode = filp->f_dentry->d_inode;
4084 struct btrfs_root *root = BTRFS_I(inode)->root;
4085 struct btrfs_item *item;
4086 struct btrfs_dir_item *di;
4087 struct btrfs_key key;
4088 struct btrfs_key found_key;
4089 struct btrfs_path *path;
4090 struct list_head ins_list;
4091 struct list_head del_list;
4093 struct extent_buffer *leaf;
4095 unsigned char d_type;
4100 int key_type = BTRFS_DIR_INDEX_KEY;
4104 int is_curr = 0; /* filp->f_pos points to the current index? */
4106 /* FIXME, use a real flag for deciding about the key type */
4107 if (root->fs_info->tree_root == root)
4108 key_type = BTRFS_DIR_ITEM_KEY;
4110 /* special case for "." */
4111 if (filp->f_pos == 0) {
4112 over = filldir(dirent, ".", 1, 1, btrfs_ino(inode), DT_DIR);
4117 /* special case for .., just use the back ref */
4118 if (filp->f_pos == 1) {
4119 u64 pino = parent_ino(filp->f_path.dentry);
4120 over = filldir(dirent, "..", 2,
4126 path = btrfs_alloc_path();
4131 if (key_type == BTRFS_DIR_INDEX_KEY) {
4132 INIT_LIST_HEAD(&ins_list);
4133 INIT_LIST_HEAD(&del_list);
4134 btrfs_get_delayed_items(inode, &ins_list, &del_list);
4137 btrfs_set_key_type(&key, key_type);
4138 key.offset = filp->f_pos;
4139 key.objectid = btrfs_ino(inode);
4141 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4146 leaf = path->nodes[0];
4147 slot = path->slots[0];
4148 if (slot >= btrfs_header_nritems(leaf)) {
4149 ret = btrfs_next_leaf(root, path);
4157 item = btrfs_item_nr(leaf, slot);
4158 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4160 if (found_key.objectid != key.objectid)
4162 if (btrfs_key_type(&found_key) != key_type)
4164 if (found_key.offset < filp->f_pos)
4166 if (key_type == BTRFS_DIR_INDEX_KEY &&
4167 btrfs_should_delete_dir_index(&del_list,
4171 filp->f_pos = found_key.offset;
4174 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
4176 di_total = btrfs_item_size(leaf, item);
4178 while (di_cur < di_total) {
4179 struct btrfs_key location;
4181 if (verify_dir_item(root, leaf, di))
4184 name_len = btrfs_dir_name_len(leaf, di);
4185 if (name_len <= sizeof(tmp_name)) {
4186 name_ptr = tmp_name;
4188 name_ptr = kmalloc(name_len, GFP_NOFS);
4194 read_extent_buffer(leaf, name_ptr,
4195 (unsigned long)(di + 1), name_len);
4197 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
4198 btrfs_dir_item_key_to_cpu(leaf, di, &location);
4200 /* is this a reference to our own snapshot? If so
4203 if (location.type == BTRFS_ROOT_ITEM_KEY &&
4204 location.objectid == root->root_key.objectid) {
4208 over = filldir(dirent, name_ptr, name_len,
4209 found_key.offset, location.objectid,
4213 if (name_ptr != tmp_name)
4218 di_len = btrfs_dir_name_len(leaf, di) +
4219 btrfs_dir_data_len(leaf, di) + sizeof(*di);
4221 di = (struct btrfs_dir_item *)((char *)di + di_len);
4227 if (key_type == BTRFS_DIR_INDEX_KEY) {
4230 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
4236 /* Reached end of directory/root. Bump pos past the last item. */
4237 if (key_type == BTRFS_DIR_INDEX_KEY)
4239 * 32-bit glibc will use getdents64, but then strtol -
4240 * so the last number we can serve is this.
4242 filp->f_pos = 0x7fffffff;
4248 if (key_type == BTRFS_DIR_INDEX_KEY)
4249 btrfs_put_delayed_items(&ins_list, &del_list);
4250 btrfs_free_path(path);
4254 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
4256 struct btrfs_root *root = BTRFS_I(inode)->root;
4257 struct btrfs_trans_handle *trans;
4259 bool nolock = false;
4261 if (BTRFS_I(inode)->dummy_inode)
4265 if (root->fs_info->closing && is_free_space_inode(root, inode))
4268 if (wbc->sync_mode == WB_SYNC_ALL) {
4270 trans = btrfs_join_transaction_nolock(root, 1);
4272 trans = btrfs_join_transaction(root, 1);
4274 return PTR_ERR(trans);
4275 btrfs_set_trans_block_group(trans, inode);
4277 ret = btrfs_end_transaction_nolock(trans, root);
4279 ret = btrfs_commit_transaction(trans, root);
4285 * This is somewhat expensive, updating the tree every time the
4286 * inode changes. But, it is most likely to find the inode in cache.
4287 * FIXME, needs more benchmarking...there are no reasons other than performance
4288 * to keep or drop this code.
4290 void btrfs_dirty_inode(struct inode *inode)
4292 struct btrfs_root *root = BTRFS_I(inode)->root;
4293 struct btrfs_trans_handle *trans;
4296 if (BTRFS_I(inode)->dummy_inode)
4299 trans = btrfs_join_transaction(root, 1);
4300 BUG_ON(IS_ERR(trans));
4301 btrfs_set_trans_block_group(trans, inode);
4303 ret = btrfs_update_inode(trans, root, inode);
4304 if (ret && ret == -ENOSPC) {
4305 /* whoops, lets try again with the full transaction */
4306 btrfs_end_transaction(trans, root);
4307 trans = btrfs_start_transaction(root, 1);
4308 if (IS_ERR(trans)) {
4309 printk_ratelimited(KERN_ERR "btrfs: fail to "
4310 "dirty inode %llu error %ld\n",
4311 (unsigned long long)btrfs_ino(inode),
4315 btrfs_set_trans_block_group(trans, inode);
4317 ret = btrfs_update_inode(trans, root, inode);
4319 printk_ratelimited(KERN_ERR "btrfs: fail to "
4320 "dirty inode %llu error %d\n",
4321 (unsigned long long)btrfs_ino(inode),
4325 btrfs_end_transaction(trans, root);
4326 if (BTRFS_I(inode)->delayed_node)
4327 btrfs_balance_delayed_items(root);
4331 * find the highest existing sequence number in a directory
4332 * and then set the in-memory index_cnt variable to reflect
4333 * free sequence numbers
4335 static int btrfs_set_inode_index_count(struct inode *inode)
4337 struct btrfs_root *root = BTRFS_I(inode)->root;
4338 struct btrfs_key key, found_key;
4339 struct btrfs_path *path;
4340 struct extent_buffer *leaf;
4343 key.objectid = btrfs_ino(inode);
4344 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4345 key.offset = (u64)-1;
4347 path = btrfs_alloc_path();
4351 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4354 /* FIXME: we should be able to handle this */
4360 * MAGIC NUMBER EXPLANATION:
4361 * since we search a directory based on f_pos we have to start at 2
4362 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4363 * else has to start at 2
4365 if (path->slots[0] == 0) {
4366 BTRFS_I(inode)->index_cnt = 2;
4372 leaf = path->nodes[0];
4373 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4375 if (found_key.objectid != btrfs_ino(inode) ||
4376 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4377 BTRFS_I(inode)->index_cnt = 2;
4381 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4383 btrfs_free_path(path);
4388 * helper to find a free sequence number in a given directory. This current
4389 * code is very simple, later versions will do smarter things in the btree
4391 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4395 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4396 ret = btrfs_inode_delayed_dir_index_count(dir);
4398 ret = btrfs_set_inode_index_count(dir);
4404 *index = BTRFS_I(dir)->index_cnt;
4405 BTRFS_I(dir)->index_cnt++;
4410 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4411 struct btrfs_root *root,
4413 const char *name, int name_len,
4414 u64 ref_objectid, u64 objectid,
4415 u64 alloc_hint, int mode, u64 *index)
4417 struct inode *inode;
4418 struct btrfs_inode_item *inode_item;
4419 struct btrfs_key *location;
4420 struct btrfs_path *path;
4421 struct btrfs_inode_ref *ref;
4422 struct btrfs_key key[2];
4428 path = btrfs_alloc_path();
4431 inode = new_inode(root->fs_info->sb);
4433 btrfs_free_path(path);
4434 return ERR_PTR(-ENOMEM);
4438 * we have to initialize this early, so we can reclaim the inode
4439 * number if we fail afterwards in this function.
4441 inode->i_ino = objectid;
4444 trace_btrfs_inode_request(dir);
4446 ret = btrfs_set_inode_index(dir, index);
4448 btrfs_free_path(path);
4450 return ERR_PTR(ret);
4454 * index_cnt is ignored for everything but a dir,
4455 * btrfs_get_inode_index_count has an explanation for the magic
4458 BTRFS_I(inode)->index_cnt = 2;
4459 BTRFS_I(inode)->root = root;
4460 BTRFS_I(inode)->generation = trans->transid;
4461 inode->i_generation = BTRFS_I(inode)->generation;
4462 btrfs_set_inode_space_info(root, inode);
4468 BTRFS_I(inode)->block_group =
4469 btrfs_find_block_group(root, 0, alloc_hint, owner);
4471 key[0].objectid = objectid;
4472 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4475 key[1].objectid = objectid;
4476 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4477 key[1].offset = ref_objectid;
4479 sizes[0] = sizeof(struct btrfs_inode_item);
4480 sizes[1] = name_len + sizeof(*ref);
4482 path->leave_spinning = 1;
4483 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4487 inode_init_owner(inode, dir, mode);
4488 inode_set_bytes(inode, 0);
4489 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4490 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4491 struct btrfs_inode_item);
4492 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4494 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4495 struct btrfs_inode_ref);
4496 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4497 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4498 ptr = (unsigned long)(ref + 1);
4499 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4501 btrfs_mark_buffer_dirty(path->nodes[0]);
4502 btrfs_free_path(path);
4504 location = &BTRFS_I(inode)->location;
4505 location->objectid = objectid;
4506 location->offset = 0;
4507 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4509 btrfs_inherit_iflags(inode, dir);
4511 if ((mode & S_IFREG)) {
4512 if (btrfs_test_opt(root, NODATASUM))
4513 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4514 if (btrfs_test_opt(root, NODATACOW) ||
4515 (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
4516 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4519 insert_inode_hash(inode);
4520 inode_tree_add(inode);
4522 trace_btrfs_inode_new(inode);
4527 BTRFS_I(dir)->index_cnt--;
4528 btrfs_free_path(path);
4530 return ERR_PTR(ret);
4533 static inline u8 btrfs_inode_type(struct inode *inode)
4535 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4539 * utility function to add 'inode' into 'parent_inode' with
4540 * a give name and a given sequence number.
4541 * if 'add_backref' is true, also insert a backref from the
4542 * inode to the parent directory.
4544 int btrfs_add_link(struct btrfs_trans_handle *trans,
4545 struct inode *parent_inode, struct inode *inode,
4546 const char *name, int name_len, int add_backref, u64 index)
4549 struct btrfs_key key;
4550 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4551 u64 ino = btrfs_ino(inode);
4552 u64 parent_ino = btrfs_ino(parent_inode);
4554 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4555 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4558 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4562 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4563 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4564 key.objectid, root->root_key.objectid,
4565 parent_ino, index, name, name_len);
4566 } else if (add_backref) {
4567 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
4572 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4574 btrfs_inode_type(inode), index);
4577 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4579 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4580 ret = btrfs_update_inode(trans, root, parent_inode);
4585 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4586 struct inode *dir, struct dentry *dentry,
4587 struct inode *inode, int backref, u64 index)
4589 int err = btrfs_add_link(trans, dir, inode,
4590 dentry->d_name.name, dentry->d_name.len,
4593 d_instantiate(dentry, inode);
4601 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4602 int mode, dev_t rdev)
4604 struct btrfs_trans_handle *trans;
4605 struct btrfs_root *root = BTRFS_I(dir)->root;
4606 struct inode *inode = NULL;
4610 unsigned long nr = 0;
4613 if (!new_valid_dev(rdev))
4617 * 2 for inode item and ref
4619 * 1 for xattr if selinux is on
4621 trans = btrfs_start_transaction(root, 5);
4623 return PTR_ERR(trans);
4625 btrfs_set_trans_block_group(trans, dir);
4627 err = btrfs_find_free_ino(root, &objectid);
4631 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4632 dentry->d_name.len, btrfs_ino(dir), objectid,
4633 BTRFS_I(dir)->block_group, mode, &index);
4634 if (IS_ERR(inode)) {
4635 err = PTR_ERR(inode);
4639 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4645 btrfs_set_trans_block_group(trans, inode);
4646 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4650 inode->i_op = &btrfs_special_inode_operations;
4651 init_special_inode(inode, inode->i_mode, rdev);
4652 btrfs_update_inode(trans, root, inode);
4654 btrfs_update_inode_block_group(trans, inode);
4655 btrfs_update_inode_block_group(trans, dir);
4657 nr = trans->blocks_used;
4658 btrfs_end_transaction_throttle(trans, root);
4659 btrfs_btree_balance_dirty(root, nr);
4661 inode_dec_link_count(inode);
4667 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4668 int mode, struct nameidata *nd)
4670 struct btrfs_trans_handle *trans;
4671 struct btrfs_root *root = BTRFS_I(dir)->root;
4672 struct inode *inode = NULL;
4675 unsigned long nr = 0;
4680 * 2 for inode item and ref
4682 * 1 for xattr if selinux is on
4684 trans = btrfs_start_transaction(root, 5);
4686 return PTR_ERR(trans);
4688 btrfs_set_trans_block_group(trans, dir);
4690 err = btrfs_find_free_ino(root, &objectid);
4694 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4695 dentry->d_name.len, btrfs_ino(dir), objectid,
4696 BTRFS_I(dir)->block_group, mode, &index);
4697 if (IS_ERR(inode)) {
4698 err = PTR_ERR(inode);
4702 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4708 btrfs_set_trans_block_group(trans, inode);
4709 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4713 inode->i_mapping->a_ops = &btrfs_aops;
4714 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4715 inode->i_fop = &btrfs_file_operations;
4716 inode->i_op = &btrfs_file_inode_operations;
4717 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4719 btrfs_update_inode_block_group(trans, inode);
4720 btrfs_update_inode_block_group(trans, dir);
4722 nr = trans->blocks_used;
4723 btrfs_end_transaction_throttle(trans, root);
4725 inode_dec_link_count(inode);
4728 btrfs_btree_balance_dirty(root, nr);
4732 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4733 struct dentry *dentry)
4735 struct btrfs_trans_handle *trans;
4736 struct btrfs_root *root = BTRFS_I(dir)->root;
4737 struct inode *inode = old_dentry->d_inode;
4739 unsigned long nr = 0;
4743 /* do not allow sys_link's with other subvols of the same device */
4744 if (root->objectid != BTRFS_I(inode)->root->objectid)
4747 if (inode->i_nlink == ~0U)
4750 err = btrfs_set_inode_index(dir, &index);
4755 * 2 items for inode and inode ref
4756 * 2 items for dir items
4757 * 1 item for parent inode
4759 trans = btrfs_start_transaction(root, 5);
4760 if (IS_ERR(trans)) {
4761 err = PTR_ERR(trans);
4765 btrfs_inc_nlink(inode);
4766 inode->i_ctime = CURRENT_TIME;
4768 btrfs_set_trans_block_group(trans, dir);
4771 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
4776 struct dentry *parent = dget_parent(dentry);
4777 btrfs_update_inode_block_group(trans, dir);
4778 err = btrfs_update_inode(trans, root, inode);
4780 btrfs_log_new_name(trans, inode, NULL, parent);
4784 nr = trans->blocks_used;
4785 btrfs_end_transaction_throttle(trans, root);
4788 inode_dec_link_count(inode);
4791 btrfs_btree_balance_dirty(root, nr);
4795 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4797 struct inode *inode = NULL;
4798 struct btrfs_trans_handle *trans;
4799 struct btrfs_root *root = BTRFS_I(dir)->root;
4801 int drop_on_err = 0;
4804 unsigned long nr = 1;
4807 * 2 items for inode and ref
4808 * 2 items for dir items
4809 * 1 for xattr if selinux is on
4811 trans = btrfs_start_transaction(root, 5);
4813 return PTR_ERR(trans);
4814 btrfs_set_trans_block_group(trans, dir);
4816 err = btrfs_find_free_ino(root, &objectid);
4820 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4821 dentry->d_name.len, btrfs_ino(dir), objectid,
4822 BTRFS_I(dir)->block_group, S_IFDIR | mode,
4824 if (IS_ERR(inode)) {
4825 err = PTR_ERR(inode);
4831 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4835 inode->i_op = &btrfs_dir_inode_operations;
4836 inode->i_fop = &btrfs_dir_file_operations;
4837 btrfs_set_trans_block_group(trans, inode);
4839 btrfs_i_size_write(inode, 0);
4840 err = btrfs_update_inode(trans, root, inode);
4844 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
4845 dentry->d_name.len, 0, index);
4849 d_instantiate(dentry, inode);
4851 btrfs_update_inode_block_group(trans, inode);
4852 btrfs_update_inode_block_group(trans, dir);
4855 nr = trans->blocks_used;
4856 btrfs_end_transaction_throttle(trans, root);
4859 btrfs_btree_balance_dirty(root, nr);
4863 /* helper for btfs_get_extent. Given an existing extent in the tree,
4864 * and an extent that you want to insert, deal with overlap and insert
4865 * the new extent into the tree.
4867 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4868 struct extent_map *existing,
4869 struct extent_map *em,
4870 u64 map_start, u64 map_len)
4874 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4875 start_diff = map_start - em->start;
4876 em->start = map_start;
4878 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4879 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4880 em->block_start += start_diff;
4881 em->block_len -= start_diff;
4883 return add_extent_mapping(em_tree, em);
4886 static noinline int uncompress_inline(struct btrfs_path *path,
4887 struct inode *inode, struct page *page,
4888 size_t pg_offset, u64 extent_offset,
4889 struct btrfs_file_extent_item *item)
4892 struct extent_buffer *leaf = path->nodes[0];
4895 unsigned long inline_size;
4899 WARN_ON(pg_offset != 0);
4900 compress_type = btrfs_file_extent_compression(leaf, item);
4901 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4902 inline_size = btrfs_file_extent_inline_item_len(leaf,
4903 btrfs_item_nr(leaf, path->slots[0]));
4904 tmp = kmalloc(inline_size, GFP_NOFS);
4907 ptr = btrfs_file_extent_inline_start(item);
4909 read_extent_buffer(leaf, tmp, ptr, inline_size);
4911 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4912 ret = btrfs_decompress(compress_type, tmp, page,
4913 extent_offset, inline_size, max_size);
4915 char *kaddr = kmap_atomic(page, KM_USER0);
4916 unsigned long copy_size = min_t(u64,
4917 PAGE_CACHE_SIZE - pg_offset,
4918 max_size - extent_offset);
4919 memset(kaddr + pg_offset, 0, copy_size);
4920 kunmap_atomic(kaddr, KM_USER0);
4927 * a bit scary, this does extent mapping from logical file offset to the disk.
4928 * the ugly parts come from merging extents from the disk with the in-ram
4929 * representation. This gets more complex because of the data=ordered code,
4930 * where the in-ram extents might be locked pending data=ordered completion.
4932 * This also copies inline extents directly into the page.
4935 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4936 size_t pg_offset, u64 start, u64 len,
4942 u64 extent_start = 0;
4944 u64 objectid = btrfs_ino(inode);
4946 struct btrfs_path *path = NULL;
4947 struct btrfs_root *root = BTRFS_I(inode)->root;
4948 struct btrfs_file_extent_item *item;
4949 struct extent_buffer *leaf;
4950 struct btrfs_key found_key;
4951 struct extent_map *em = NULL;
4952 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4953 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4954 struct btrfs_trans_handle *trans = NULL;
4958 read_lock(&em_tree->lock);
4959 em = lookup_extent_mapping(em_tree, start, len);
4961 em->bdev = root->fs_info->fs_devices->latest_bdev;
4962 read_unlock(&em_tree->lock);
4965 if (em->start > start || em->start + em->len <= start)
4966 free_extent_map(em);
4967 else if (em->block_start == EXTENT_MAP_INLINE && page)
4968 free_extent_map(em);
4972 em = alloc_extent_map();
4977 em->bdev = root->fs_info->fs_devices->latest_bdev;
4978 em->start = EXTENT_MAP_HOLE;
4979 em->orig_start = EXTENT_MAP_HOLE;
4981 em->block_len = (u64)-1;
4984 path = btrfs_alloc_path();
4988 ret = btrfs_lookup_file_extent(trans, root, path,
4989 objectid, start, trans != NULL);
4996 if (path->slots[0] == 0)
5001 leaf = path->nodes[0];
5002 item = btrfs_item_ptr(leaf, path->slots[0],
5003 struct btrfs_file_extent_item);
5004 /* are we inside the extent that was found? */
5005 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5006 found_type = btrfs_key_type(&found_key);
5007 if (found_key.objectid != objectid ||
5008 found_type != BTRFS_EXTENT_DATA_KEY) {
5012 found_type = btrfs_file_extent_type(leaf, item);
5013 extent_start = found_key.offset;
5014 compress_type = btrfs_file_extent_compression(leaf, item);
5015 if (found_type == BTRFS_FILE_EXTENT_REG ||
5016 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5017 extent_end = extent_start +
5018 btrfs_file_extent_num_bytes(leaf, item);
5019 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5021 size = btrfs_file_extent_inline_len(leaf, item);
5022 extent_end = (extent_start + size + root->sectorsize - 1) &
5023 ~((u64)root->sectorsize - 1);
5026 if (start >= extent_end) {
5028 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
5029 ret = btrfs_next_leaf(root, path);
5036 leaf = path->nodes[0];
5038 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5039 if (found_key.objectid != objectid ||
5040 found_key.type != BTRFS_EXTENT_DATA_KEY)
5042 if (start + len <= found_key.offset)
5045 em->len = found_key.offset - start;
5049 if (found_type == BTRFS_FILE_EXTENT_REG ||
5050 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5051 em->start = extent_start;
5052 em->len = extent_end - extent_start;
5053 em->orig_start = extent_start -
5054 btrfs_file_extent_offset(leaf, item);
5055 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
5057 em->block_start = EXTENT_MAP_HOLE;
5060 if (compress_type != BTRFS_COMPRESS_NONE) {
5061 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5062 em->compress_type = compress_type;
5063 em->block_start = bytenr;
5064 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
5067 bytenr += btrfs_file_extent_offset(leaf, item);
5068 em->block_start = bytenr;
5069 em->block_len = em->len;
5070 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
5071 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
5074 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5078 size_t extent_offset;
5081 em->block_start = EXTENT_MAP_INLINE;
5082 if (!page || create) {
5083 em->start = extent_start;
5084 em->len = extent_end - extent_start;
5088 size = btrfs_file_extent_inline_len(leaf, item);
5089 extent_offset = page_offset(page) + pg_offset - extent_start;
5090 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
5091 size - extent_offset);
5092 em->start = extent_start + extent_offset;
5093 em->len = (copy_size + root->sectorsize - 1) &
5094 ~((u64)root->sectorsize - 1);
5095 em->orig_start = EXTENT_MAP_INLINE;
5096 if (compress_type) {
5097 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5098 em->compress_type = compress_type;
5100 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
5101 if (create == 0 && !PageUptodate(page)) {
5102 if (btrfs_file_extent_compression(leaf, item) !=
5103 BTRFS_COMPRESS_NONE) {
5104 ret = uncompress_inline(path, inode, page,
5106 extent_offset, item);
5110 read_extent_buffer(leaf, map + pg_offset, ptr,
5112 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
5113 memset(map + pg_offset + copy_size, 0,
5114 PAGE_CACHE_SIZE - pg_offset -
5119 flush_dcache_page(page);
5120 } else if (create && PageUptodate(page)) {
5124 free_extent_map(em);
5126 btrfs_release_path(path);
5127 trans = btrfs_join_transaction(root, 1);
5129 return ERR_CAST(trans);
5133 write_extent_buffer(leaf, map + pg_offset, ptr,
5136 btrfs_mark_buffer_dirty(leaf);
5138 set_extent_uptodate(io_tree, em->start,
5139 extent_map_end(em) - 1, NULL, GFP_NOFS);
5142 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
5149 em->block_start = EXTENT_MAP_HOLE;
5150 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
5152 btrfs_release_path(path);
5153 if (em->start > start || extent_map_end(em) <= start) {
5154 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
5155 "[%llu %llu]\n", (unsigned long long)em->start,
5156 (unsigned long long)em->len,
5157 (unsigned long long)start,
5158 (unsigned long long)len);
5164 write_lock(&em_tree->lock);
5165 ret = add_extent_mapping(em_tree, em);
5166 /* it is possible that someone inserted the extent into the tree
5167 * while we had the lock dropped. It is also possible that
5168 * an overlapping map exists in the tree
5170 if (ret == -EEXIST) {
5171 struct extent_map *existing;
5175 existing = lookup_extent_mapping(em_tree, start, len);
5176 if (existing && (existing->start > start ||
5177 existing->start + existing->len <= start)) {
5178 free_extent_map(existing);
5182 existing = lookup_extent_mapping(em_tree, em->start,
5185 err = merge_extent_mapping(em_tree, existing,
5188 free_extent_map(existing);
5190 free_extent_map(em);
5195 free_extent_map(em);
5199 free_extent_map(em);
5204 write_unlock(&em_tree->lock);
5207 trace_btrfs_get_extent(root, em);
5210 btrfs_free_path(path);
5212 ret = btrfs_end_transaction(trans, root);
5217 free_extent_map(em);
5218 return ERR_PTR(err);
5223 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
5224 size_t pg_offset, u64 start, u64 len,
5227 struct extent_map *em;
5228 struct extent_map *hole_em = NULL;
5229 u64 range_start = start;
5235 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
5240 * if our em maps to a hole, there might
5241 * actually be delalloc bytes behind it
5243 if (em->block_start != EXTENT_MAP_HOLE)
5249 /* check to see if we've wrapped (len == -1 or similar) */
5258 /* ok, we didn't find anything, lets look for delalloc */
5259 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
5260 end, len, EXTENT_DELALLOC, 1);
5261 found_end = range_start + found;
5262 if (found_end < range_start)
5263 found_end = (u64)-1;
5266 * we didn't find anything useful, return
5267 * the original results from get_extent()
5269 if (range_start > end || found_end <= start) {
5275 /* adjust the range_start to make sure it doesn't
5276 * go backwards from the start they passed in
5278 range_start = max(start,range_start);
5279 found = found_end - range_start;
5282 u64 hole_start = start;
5285 em = alloc_extent_map();
5291 * when btrfs_get_extent can't find anything it
5292 * returns one huge hole
5294 * make sure what it found really fits our range, and
5295 * adjust to make sure it is based on the start from
5299 u64 calc_end = extent_map_end(hole_em);
5301 if (calc_end <= start || (hole_em->start > end)) {
5302 free_extent_map(hole_em);
5305 hole_start = max(hole_em->start, start);
5306 hole_len = calc_end - hole_start;
5310 if (hole_em && range_start > hole_start) {
5311 /* our hole starts before our delalloc, so we
5312 * have to return just the parts of the hole
5313 * that go until the delalloc starts
5315 em->len = min(hole_len,
5316 range_start - hole_start);
5317 em->start = hole_start;
5318 em->orig_start = hole_start;
5320 * don't adjust block start at all,
5321 * it is fixed at EXTENT_MAP_HOLE
5323 em->block_start = hole_em->block_start;
5324 em->block_len = hole_len;
5326 em->start = range_start;
5328 em->orig_start = range_start;
5329 em->block_start = EXTENT_MAP_DELALLOC;
5330 em->block_len = found;
5332 } else if (hole_em) {
5337 free_extent_map(hole_em);
5339 free_extent_map(em);
5340 return ERR_PTR(err);
5345 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
5346 struct extent_map *em,
5349 struct btrfs_root *root = BTRFS_I(inode)->root;
5350 struct btrfs_trans_handle *trans;
5351 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5352 struct btrfs_key ins;
5355 bool insert = false;
5358 * Ok if the extent map we looked up is a hole and is for the exact
5359 * range we want, there is no reason to allocate a new one, however if
5360 * it is not right then we need to free this one and drop the cache for
5363 if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
5365 free_extent_map(em);
5368 btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
5371 trans = btrfs_join_transaction(root, 0);
5373 return ERR_CAST(trans);
5375 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5377 alloc_hint = get_extent_allocation_hint(inode, start, len);
5378 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
5379 alloc_hint, (u64)-1, &ins, 1);
5386 em = alloc_extent_map();
5388 em = ERR_PTR(-ENOMEM);
5394 em->orig_start = em->start;
5395 em->len = ins.offset;
5397 em->block_start = ins.objectid;
5398 em->block_len = ins.offset;
5399 em->bdev = root->fs_info->fs_devices->latest_bdev;
5402 * We need to do this because if we're using the original em we searched
5403 * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
5406 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5409 write_lock(&em_tree->lock);
5410 ret = add_extent_mapping(em_tree, em);
5411 write_unlock(&em_tree->lock);
5414 btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
5417 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
5418 ins.offset, ins.offset, 0);
5420 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
5424 btrfs_end_transaction(trans, root);
5429 * returns 1 when the nocow is safe, < 1 on error, 0 if the
5430 * block must be cow'd
5432 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
5433 struct inode *inode, u64 offset, u64 len)
5435 struct btrfs_path *path;
5437 struct extent_buffer *leaf;
5438 struct btrfs_root *root = BTRFS_I(inode)->root;
5439 struct btrfs_file_extent_item *fi;
5440 struct btrfs_key key;
5448 path = btrfs_alloc_path();
5452 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
5457 slot = path->slots[0];
5460 /* can't find the item, must cow */
5467 leaf = path->nodes[0];
5468 btrfs_item_key_to_cpu(leaf, &key, slot);
5469 if (key.objectid != btrfs_ino(inode) ||
5470 key.type != BTRFS_EXTENT_DATA_KEY) {
5471 /* not our file or wrong item type, must cow */
5475 if (key.offset > offset) {
5476 /* Wrong offset, must cow */
5480 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5481 found_type = btrfs_file_extent_type(leaf, fi);
5482 if (found_type != BTRFS_FILE_EXTENT_REG &&
5483 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
5484 /* not a regular extent, must cow */
5487 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5488 backref_offset = btrfs_file_extent_offset(leaf, fi);
5490 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
5491 if (extent_end < offset + len) {
5492 /* extent doesn't include our full range, must cow */
5496 if (btrfs_extent_readonly(root, disk_bytenr))
5500 * look for other files referencing this extent, if we
5501 * find any we must cow
5503 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
5504 key.offset - backref_offset, disk_bytenr))
5508 * adjust disk_bytenr and num_bytes to cover just the bytes
5509 * in this extent we are about to write. If there
5510 * are any csums in that range we have to cow in order
5511 * to keep the csums correct
5513 disk_bytenr += backref_offset;
5514 disk_bytenr += offset - key.offset;
5515 num_bytes = min(offset + len, extent_end) - offset;
5516 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
5519 * all of the above have passed, it is safe to overwrite this extent
5524 btrfs_free_path(path);
5528 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
5529 struct buffer_head *bh_result, int create)
5531 struct extent_map *em;
5532 struct btrfs_root *root = BTRFS_I(inode)->root;
5533 u64 start = iblock << inode->i_blkbits;
5534 u64 len = bh_result->b_size;
5535 struct btrfs_trans_handle *trans;
5537 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
5542 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
5543 * io. INLINE is special, and we could probably kludge it in here, but
5544 * it's still buffered so for safety lets just fall back to the generic
5547 * For COMPRESSED we _have_ to read the entire extent in so we can
5548 * decompress it, so there will be buffering required no matter what we
5549 * do, so go ahead and fallback to buffered.
5551 * We return -ENOTBLK because thats what makes DIO go ahead and go back
5552 * to buffered IO. Don't blame me, this is the price we pay for using
5555 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
5556 em->block_start == EXTENT_MAP_INLINE) {
5557 free_extent_map(em);
5561 /* Just a good old fashioned hole, return */
5562 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
5563 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5564 free_extent_map(em);
5565 /* DIO will do one hole at a time, so just unlock a sector */
5566 unlock_extent(&BTRFS_I(inode)->io_tree, start,
5567 start + root->sectorsize - 1, GFP_NOFS);
5572 * We don't allocate a new extent in the following cases
5574 * 1) The inode is marked as NODATACOW. In this case we'll just use the
5576 * 2) The extent is marked as PREALLOC. We're good to go here and can
5577 * just use the extent.
5581 len = em->len - (start - em->start);
5585 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
5586 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
5587 em->block_start != EXTENT_MAP_HOLE)) {
5592 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5593 type = BTRFS_ORDERED_PREALLOC;
5595 type = BTRFS_ORDERED_NOCOW;
5596 len = min(len, em->len - (start - em->start));
5597 block_start = em->block_start + (start - em->start);
5600 * we're not going to log anything, but we do need
5601 * to make sure the current transaction stays open
5602 * while we look for nocow cross refs
5604 trans = btrfs_join_transaction(root, 0);
5608 if (can_nocow_odirect(trans, inode, start, len) == 1) {
5609 ret = btrfs_add_ordered_extent_dio(inode, start,
5610 block_start, len, len, type);
5611 btrfs_end_transaction(trans, root);
5613 free_extent_map(em);
5618 btrfs_end_transaction(trans, root);
5622 * this will cow the extent, reset the len in case we changed
5625 len = bh_result->b_size;
5626 em = btrfs_new_extent_direct(inode, em, start, len);
5629 len = min(len, em->len - (start - em->start));
5631 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1,
5632 EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1,
5635 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
5637 bh_result->b_size = len;
5638 bh_result->b_bdev = em->bdev;
5639 set_buffer_mapped(bh_result);
5640 if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5641 set_buffer_new(bh_result);
5643 free_extent_map(em);
5648 struct btrfs_dio_private {
5649 struct inode *inode;
5656 /* number of bios pending for this dio */
5657 atomic_t pending_bios;
5662 struct bio *orig_bio;
5665 static void btrfs_endio_direct_read(struct bio *bio, int err)
5667 struct btrfs_dio_private *dip = bio->bi_private;
5668 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
5669 struct bio_vec *bvec = bio->bi_io_vec;
5670 struct inode *inode = dip->inode;
5671 struct btrfs_root *root = BTRFS_I(inode)->root;
5673 u32 *private = dip->csums;
5675 start = dip->logical_offset;
5677 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
5678 struct page *page = bvec->bv_page;
5681 unsigned long flags;
5683 local_irq_save(flags);
5684 kaddr = kmap_atomic(page, KM_IRQ0);
5685 csum = btrfs_csum_data(root, kaddr + bvec->bv_offset,
5686 csum, bvec->bv_len);
5687 btrfs_csum_final(csum, (char *)&csum);
5688 kunmap_atomic(kaddr, KM_IRQ0);
5689 local_irq_restore(flags);
5691 flush_dcache_page(bvec->bv_page);
5692 if (csum != *private) {
5693 printk(KERN_ERR "btrfs csum failed ino %llu off"
5694 " %llu csum %u private %u\n",
5695 (unsigned long long)btrfs_ino(inode),
5696 (unsigned long long)start,
5702 start += bvec->bv_len;
5705 } while (bvec <= bvec_end);
5707 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
5708 dip->logical_offset + dip->bytes - 1, GFP_NOFS);
5709 bio->bi_private = dip->private;
5714 /* If we had a csum failure make sure to clear the uptodate flag */
5716 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5717 dio_end_io(bio, err);
5720 static void btrfs_endio_direct_write(struct bio *bio, int err)
5722 struct btrfs_dio_private *dip = bio->bi_private;
5723 struct inode *inode = dip->inode;
5724 struct btrfs_root *root = BTRFS_I(inode)->root;
5725 struct btrfs_trans_handle *trans;
5726 struct btrfs_ordered_extent *ordered = NULL;
5727 struct extent_state *cached_state = NULL;
5728 u64 ordered_offset = dip->logical_offset;
5729 u64 ordered_bytes = dip->bytes;
5735 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
5743 trans = btrfs_join_transaction(root, 1);
5744 if (IS_ERR(trans)) {
5748 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5750 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
5751 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5753 ret = btrfs_update_inode(trans, root, inode);
5758 lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5759 ordered->file_offset + ordered->len - 1, 0,
5760 &cached_state, GFP_NOFS);
5762 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) {
5763 ret = btrfs_mark_extent_written(trans, inode,
5764 ordered->file_offset,
5765 ordered->file_offset +
5772 ret = insert_reserved_file_extent(trans, inode,
5773 ordered->file_offset,
5779 BTRFS_FILE_EXTENT_REG);
5780 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
5781 ordered->file_offset, ordered->len);
5789 add_pending_csums(trans, inode, ordered->file_offset, &ordered->list);
5790 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5792 btrfs_update_inode(trans, root, inode);
5795 unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5796 ordered->file_offset + ordered->len - 1,
5797 &cached_state, GFP_NOFS);
5799 btrfs_delalloc_release_metadata(inode, ordered->len);
5800 btrfs_end_transaction(trans, root);
5801 ordered_offset = ordered->file_offset + ordered->len;
5802 btrfs_put_ordered_extent(ordered);
5803 btrfs_put_ordered_extent(ordered);
5807 * our bio might span multiple ordered extents. If we haven't
5808 * completed the accounting for the whole dio, go back and try again
5810 if (ordered_offset < dip->logical_offset + dip->bytes) {
5811 ordered_bytes = dip->logical_offset + dip->bytes -
5816 bio->bi_private = dip->private;
5821 /* If we had an error make sure to clear the uptodate flag */
5823 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5824 dio_end_io(bio, err);
5827 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
5828 struct bio *bio, int mirror_num,
5829 unsigned long bio_flags, u64 offset)
5832 struct btrfs_root *root = BTRFS_I(inode)->root;
5833 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
5838 static void btrfs_end_dio_bio(struct bio *bio, int err)
5840 struct btrfs_dio_private *dip = bio->bi_private;
5843 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
5844 "sector %#Lx len %u err no %d\n",
5845 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
5846 (unsigned long long)bio->bi_sector, bio->bi_size, err);
5850 * before atomic variable goto zero, we must make sure
5851 * dip->errors is perceived to be set.
5853 smp_mb__before_atomic_dec();
5856 /* if there are more bios still pending for this dio, just exit */
5857 if (!atomic_dec_and_test(&dip->pending_bios))
5861 bio_io_error(dip->orig_bio);
5863 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
5864 bio_endio(dip->orig_bio, 0);
5870 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
5871 u64 first_sector, gfp_t gfp_flags)
5873 int nr_vecs = bio_get_nr_vecs(bdev);
5874 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
5877 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
5878 int rw, u64 file_offset, int skip_sum,
5879 u32 *csums, int async_submit)
5881 int write = rw & REQ_WRITE;
5882 struct btrfs_root *root = BTRFS_I(inode)->root;
5886 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
5893 if (write && async_submit) {
5894 ret = btrfs_wq_submit_bio(root->fs_info,
5895 inode, rw, bio, 0, 0,
5897 __btrfs_submit_bio_start_direct_io,
5898 __btrfs_submit_bio_done);
5902 * If we aren't doing async submit, calculate the csum of the
5905 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
5908 } else if (!skip_sum) {
5909 ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
5910 file_offset, csums);
5916 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
5922 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
5925 struct inode *inode = dip->inode;
5926 struct btrfs_root *root = BTRFS_I(inode)->root;
5927 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5929 struct bio *orig_bio = dip->orig_bio;
5930 struct bio_vec *bvec = orig_bio->bi_io_vec;
5931 u64 start_sector = orig_bio->bi_sector;
5932 u64 file_offset = dip->logical_offset;
5936 u32 *csums = dip->csums;
5938 int async_submit = 0;
5939 int write = rw & REQ_WRITE;
5941 map_length = orig_bio->bi_size;
5942 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5943 &map_length, NULL, 0);
5949 if (map_length >= orig_bio->bi_size) {
5955 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
5958 bio->bi_private = dip;
5959 bio->bi_end_io = btrfs_end_dio_bio;
5960 atomic_inc(&dip->pending_bios);
5962 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
5963 if (unlikely(map_length < submit_len + bvec->bv_len ||
5964 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5965 bvec->bv_offset) < bvec->bv_len)) {
5967 * inc the count before we submit the bio so
5968 * we know the end IO handler won't happen before
5969 * we inc the count. Otherwise, the dip might get freed
5970 * before we're done setting it up
5972 atomic_inc(&dip->pending_bios);
5973 ret = __btrfs_submit_dio_bio(bio, inode, rw,
5974 file_offset, skip_sum,
5975 csums, async_submit);
5978 atomic_dec(&dip->pending_bios);
5982 /* Write's use the ordered csums */
5983 if (!write && !skip_sum)
5984 csums = csums + nr_pages;
5985 start_sector += submit_len >> 9;
5986 file_offset += submit_len;
5991 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
5992 start_sector, GFP_NOFS);
5995 bio->bi_private = dip;
5996 bio->bi_end_io = btrfs_end_dio_bio;
5998 map_length = orig_bio->bi_size;
5999 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
6000 &map_length, NULL, 0);
6006 submit_len += bvec->bv_len;
6013 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
6014 csums, async_submit);
6022 * before atomic variable goto zero, we must
6023 * make sure dip->errors is perceived to be set.
6025 smp_mb__before_atomic_dec();
6026 if (atomic_dec_and_test(&dip->pending_bios))
6027 bio_io_error(dip->orig_bio);
6029 /* bio_end_io() will handle error, so we needn't return it */
6033 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
6036 struct btrfs_root *root = BTRFS_I(inode)->root;
6037 struct btrfs_dio_private *dip;
6038 struct bio_vec *bvec = bio->bi_io_vec;
6040 int write = rw & REQ_WRITE;
6043 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
6045 dip = kmalloc(sizeof(*dip), GFP_NOFS);
6052 /* Write's use the ordered csum stuff, so we don't need dip->csums */
6053 if (!write && !skip_sum) {
6054 dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS);
6062 dip->private = bio->bi_private;
6064 dip->logical_offset = file_offset;
6068 dip->bytes += bvec->bv_len;
6070 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
6072 dip->disk_bytenr = (u64)bio->bi_sector << 9;
6073 bio->bi_private = dip;
6075 dip->orig_bio = bio;
6076 atomic_set(&dip->pending_bios, 0);
6079 bio->bi_end_io = btrfs_endio_direct_write;
6081 bio->bi_end_io = btrfs_endio_direct_read;
6083 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
6088 * If this is a write, we need to clean up the reserved space and kill
6089 * the ordered extent.
6092 struct btrfs_ordered_extent *ordered;
6093 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
6094 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
6095 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
6096 btrfs_free_reserved_extent(root, ordered->start,
6098 btrfs_put_ordered_extent(ordered);
6099 btrfs_put_ordered_extent(ordered);
6101 bio_endio(bio, ret);
6104 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
6105 const struct iovec *iov, loff_t offset,
6106 unsigned long nr_segs)
6112 unsigned blocksize_mask = root->sectorsize - 1;
6113 ssize_t retval = -EINVAL;
6114 loff_t end = offset;
6116 if (offset & blocksize_mask)
6119 /* Check the memory alignment. Blocks cannot straddle pages */
6120 for (seg = 0; seg < nr_segs; seg++) {
6121 addr = (unsigned long)iov[seg].iov_base;
6122 size = iov[seg].iov_len;
6124 if ((addr & blocksize_mask) || (size & blocksize_mask))
6127 /* If this is a write we don't need to check anymore */
6132 * Check to make sure we don't have duplicate iov_base's in this
6133 * iovec, if so return EINVAL, otherwise we'll get csum errors
6134 * when reading back.
6136 for (i = seg + 1; i < nr_segs; i++) {
6137 if (iov[seg].iov_base == iov[i].iov_base)
6145 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
6146 const struct iovec *iov, loff_t offset,
6147 unsigned long nr_segs)
6149 struct file *file = iocb->ki_filp;
6150 struct inode *inode = file->f_mapping->host;
6151 struct btrfs_ordered_extent *ordered;
6152 struct extent_state *cached_state = NULL;
6153 u64 lockstart, lockend;
6155 int writing = rw & WRITE;
6157 size_t count = iov_length(iov, nr_segs);
6159 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
6165 lockend = offset + count - 1;
6168 ret = btrfs_delalloc_reserve_space(inode, count);
6174 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6175 0, &cached_state, GFP_NOFS);
6177 * We're concerned with the entire range that we're going to be
6178 * doing DIO to, so we need to make sure theres no ordered
6179 * extents in this range.
6181 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6182 lockend - lockstart + 1);
6185 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6186 &cached_state, GFP_NOFS);
6187 btrfs_start_ordered_extent(inode, ordered, 1);
6188 btrfs_put_ordered_extent(ordered);
6193 * we don't use btrfs_set_extent_delalloc because we don't want
6194 * the dirty or uptodate bits
6197 write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING;
6198 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6199 EXTENT_DELALLOC, 0, NULL, &cached_state,
6202 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6203 lockend, EXTENT_LOCKED | write_bits,
6204 1, 0, &cached_state, GFP_NOFS);
6209 free_extent_state(cached_state);
6210 cached_state = NULL;
6212 ret = __blockdev_direct_IO(rw, iocb, inode,
6213 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
6214 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
6215 btrfs_submit_direct, 0);
6217 if (ret < 0 && ret != -EIOCBQUEUED) {
6218 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset,
6219 offset + iov_length(iov, nr_segs) - 1,
6220 EXTENT_LOCKED | write_bits, 1, 0,
6221 &cached_state, GFP_NOFS);
6222 } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) {
6224 * We're falling back to buffered, unlock the section we didn't
6227 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret,
6228 offset + iov_length(iov, nr_segs) - 1,
6229 EXTENT_LOCKED | write_bits, 1, 0,
6230 &cached_state, GFP_NOFS);
6233 free_extent_state(cached_state);
6237 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
6238 __u64 start, __u64 len)
6240 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
6243 int btrfs_readpage(struct file *file, struct page *page)
6245 struct extent_io_tree *tree;
6246 tree = &BTRFS_I(page->mapping->host)->io_tree;
6247 return extent_read_full_page(tree, page, btrfs_get_extent);
6250 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
6252 struct extent_io_tree *tree;
6255 if (current->flags & PF_MEMALLOC) {
6256 redirty_page_for_writepage(wbc, page);
6260 tree = &BTRFS_I(page->mapping->host)->io_tree;
6261 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
6264 int btrfs_writepages(struct address_space *mapping,
6265 struct writeback_control *wbc)
6267 struct extent_io_tree *tree;
6269 tree = &BTRFS_I(mapping->host)->io_tree;
6270 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
6274 btrfs_readpages(struct file *file, struct address_space *mapping,
6275 struct list_head *pages, unsigned nr_pages)
6277 struct extent_io_tree *tree;
6278 tree = &BTRFS_I(mapping->host)->io_tree;
6279 return extent_readpages(tree, mapping, pages, nr_pages,
6282 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6284 struct extent_io_tree *tree;
6285 struct extent_map_tree *map;
6288 tree = &BTRFS_I(page->mapping->host)->io_tree;
6289 map = &BTRFS_I(page->mapping->host)->extent_tree;
6290 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
6292 ClearPagePrivate(page);
6293 set_page_private(page, 0);
6294 page_cache_release(page);
6299 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6301 if (PageWriteback(page) || PageDirty(page))
6303 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
6306 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
6308 struct extent_io_tree *tree;
6309 struct btrfs_ordered_extent *ordered;
6310 struct extent_state *cached_state = NULL;
6311 u64 page_start = page_offset(page);
6312 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
6316 * we have the page locked, so new writeback can't start,
6317 * and the dirty bit won't be cleared while we are here.
6319 * Wait for IO on this page so that we can safely clear
6320 * the PagePrivate2 bit and do ordered accounting
6322 wait_on_page_writeback(page);
6324 tree = &BTRFS_I(page->mapping->host)->io_tree;
6326 btrfs_releasepage(page, GFP_NOFS);
6329 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6331 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
6335 * IO on this page will never be started, so we need
6336 * to account for any ordered extents now
6338 clear_extent_bit(tree, page_start, page_end,
6339 EXTENT_DIRTY | EXTENT_DELALLOC |
6340 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
6341 &cached_state, GFP_NOFS);
6343 * whoever cleared the private bit is responsible
6344 * for the finish_ordered_io
6346 if (TestClearPagePrivate2(page)) {
6347 btrfs_finish_ordered_io(page->mapping->host,
6348 page_start, page_end);
6350 btrfs_put_ordered_extent(ordered);
6351 cached_state = NULL;
6352 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6355 clear_extent_bit(tree, page_start, page_end,
6356 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
6357 EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS);
6358 __btrfs_releasepage(page, GFP_NOFS);
6360 ClearPageChecked(page);
6361 if (PagePrivate(page)) {
6362 ClearPagePrivate(page);
6363 set_page_private(page, 0);
6364 page_cache_release(page);
6369 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
6370 * called from a page fault handler when a page is first dirtied. Hence we must
6371 * be careful to check for EOF conditions here. We set the page up correctly
6372 * for a written page which means we get ENOSPC checking when writing into
6373 * holes and correct delalloc and unwritten extent mapping on filesystems that
6374 * support these features.
6376 * We are not allowed to take the i_mutex here so we have to play games to
6377 * protect against truncate races as the page could now be beyond EOF. Because
6378 * vmtruncate() writes the inode size before removing pages, once we have the
6379 * page lock we can determine safely if the page is beyond EOF. If it is not
6380 * beyond EOF, then the page is guaranteed safe against truncation until we
6383 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
6385 struct page *page = vmf->page;
6386 struct inode *inode = fdentry(vma->vm_file)->d_inode;
6387 struct btrfs_root *root = BTRFS_I(inode)->root;
6388 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6389 struct btrfs_ordered_extent *ordered;
6390 struct extent_state *cached_state = NULL;
6392 unsigned long zero_start;
6398 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
6402 else /* -ENOSPC, -EIO, etc */
6403 ret = VM_FAULT_SIGBUS;
6407 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
6410 size = i_size_read(inode);
6411 page_start = page_offset(page);
6412 page_end = page_start + PAGE_CACHE_SIZE - 1;
6414 if ((page->mapping != inode->i_mapping) ||
6415 (page_start >= size)) {
6416 /* page got truncated out from underneath us */
6419 wait_on_page_writeback(page);
6421 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
6423 set_page_extent_mapped(page);
6426 * we can't set the delalloc bits if there are pending ordered
6427 * extents. Drop our locks and wait for them to finish
6429 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6431 unlock_extent_cached(io_tree, page_start, page_end,
6432 &cached_state, GFP_NOFS);
6434 btrfs_start_ordered_extent(inode, ordered, 1);
6435 btrfs_put_ordered_extent(ordered);
6440 * XXX - page_mkwrite gets called every time the page is dirtied, even
6441 * if it was already dirty, so for space accounting reasons we need to
6442 * clear any delalloc bits for the range we are fixing to save. There
6443 * is probably a better way to do this, but for now keep consistent with
6444 * prepare_pages in the normal write path.
6446 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
6447 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
6448 0, 0, &cached_state, GFP_NOFS);
6450 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
6453 unlock_extent_cached(io_tree, page_start, page_end,
6454 &cached_state, GFP_NOFS);
6455 ret = VM_FAULT_SIGBUS;
6460 /* page is wholly or partially inside EOF */
6461 if (page_start + PAGE_CACHE_SIZE > size)
6462 zero_start = size & ~PAGE_CACHE_MASK;
6464 zero_start = PAGE_CACHE_SIZE;
6466 if (zero_start != PAGE_CACHE_SIZE) {
6468 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
6469 flush_dcache_page(page);
6472 ClearPageChecked(page);
6473 set_page_dirty(page);
6474 SetPageUptodate(page);
6476 BTRFS_I(inode)->last_trans = root->fs_info->generation;
6477 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
6479 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
6483 return VM_FAULT_LOCKED;
6485 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
6490 static int btrfs_truncate(struct inode *inode)
6492 struct btrfs_root *root = BTRFS_I(inode)->root;
6495 struct btrfs_trans_handle *trans;
6497 u64 mask = root->sectorsize - 1;
6499 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
6503 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
6504 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
6506 trans = btrfs_start_transaction(root, 5);
6508 return PTR_ERR(trans);
6510 btrfs_set_trans_block_group(trans, inode);
6512 ret = btrfs_orphan_add(trans, inode);
6514 btrfs_end_transaction(trans, root);
6518 nr = trans->blocks_used;
6519 btrfs_end_transaction(trans, root);
6520 btrfs_btree_balance_dirty(root, nr);
6522 /* Now start a transaction for the truncate */
6523 trans = btrfs_start_transaction(root, 0);
6525 return PTR_ERR(trans);
6526 btrfs_set_trans_block_group(trans, inode);
6527 trans->block_rsv = root->orphan_block_rsv;
6530 * setattr is responsible for setting the ordered_data_close flag,
6531 * but that is only tested during the last file release. That
6532 * could happen well after the next commit, leaving a great big
6533 * window where new writes may get lost if someone chooses to write
6534 * to this file after truncating to zero
6536 * The inode doesn't have any dirty data here, and so if we commit
6537 * this is a noop. If someone immediately starts writing to the inode
6538 * it is very likely we'll catch some of their writes in this
6539 * transaction, and the commit will find this file on the ordered
6540 * data list with good things to send down.
6542 * This is a best effort solution, there is still a window where
6543 * using truncate to replace the contents of the file will
6544 * end up with a zero length file after a crash.
6546 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
6547 btrfs_add_ordered_operation(trans, root, inode);
6551 trans = btrfs_start_transaction(root, 0);
6553 return PTR_ERR(trans);
6554 btrfs_set_trans_block_group(trans, inode);
6555 trans->block_rsv = root->orphan_block_rsv;
6558 ret = btrfs_block_rsv_check(trans, root,
6559 root->orphan_block_rsv, 0, 5);
6560 if (ret == -EAGAIN) {
6561 ret = btrfs_commit_transaction(trans, root);
6571 ret = btrfs_truncate_inode_items(trans, root, inode,
6573 BTRFS_EXTENT_DATA_KEY);
6574 if (ret != -EAGAIN) {
6579 ret = btrfs_update_inode(trans, root, inode);
6585 nr = trans->blocks_used;
6586 btrfs_end_transaction(trans, root);
6588 btrfs_btree_balance_dirty(root, nr);
6591 if (ret == 0 && inode->i_nlink > 0) {
6592 ret = btrfs_orphan_del(trans, inode);
6595 } else if (ret && inode->i_nlink > 0) {
6597 * Failed to do the truncate, remove us from the in memory
6600 ret = btrfs_orphan_del(NULL, inode);
6603 ret = btrfs_update_inode(trans, root, inode);
6607 nr = trans->blocks_used;
6608 ret = btrfs_end_transaction_throttle(trans, root);
6611 btrfs_btree_balance_dirty(root, nr);
6617 * create a new subvolume directory/inode (helper for the ioctl).
6619 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
6620 struct btrfs_root *new_root,
6621 u64 new_dirid, u64 alloc_hint)
6623 struct inode *inode;
6627 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
6628 new_dirid, alloc_hint, S_IFDIR | 0700, &index);
6630 return PTR_ERR(inode);
6631 inode->i_op = &btrfs_dir_inode_operations;
6632 inode->i_fop = &btrfs_dir_file_operations;
6635 btrfs_i_size_write(inode, 0);
6637 err = btrfs_update_inode(trans, new_root, inode);
6644 /* helper function for file defrag and space balancing. This
6645 * forces readahead on a given range of bytes in an inode
6647 unsigned long btrfs_force_ra(struct address_space *mapping,
6648 struct file_ra_state *ra, struct file *file,
6649 pgoff_t offset, pgoff_t last_index)
6651 pgoff_t req_size = last_index - offset + 1;
6653 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
6654 return offset + req_size;
6657 struct inode *btrfs_alloc_inode(struct super_block *sb)
6659 struct btrfs_inode *ei;
6660 struct inode *inode;
6662 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
6667 ei->space_info = NULL;
6671 ei->last_sub_trans = 0;
6672 ei->logged_trans = 0;
6673 ei->delalloc_bytes = 0;
6674 ei->reserved_bytes = 0;
6675 ei->disk_i_size = 0;
6677 ei->index_cnt = (u64)-1;
6678 ei->last_unlink_trans = 0;
6680 atomic_set(&ei->outstanding_extents, 0);
6681 atomic_set(&ei->reserved_extents, 0);
6683 ei->ordered_data_close = 0;
6684 ei->orphan_meta_reserved = 0;
6685 ei->dummy_inode = 0;
6686 ei->force_compress = BTRFS_COMPRESS_NONE;
6688 ei->delayed_node = NULL;
6690 inode = &ei->vfs_inode;
6691 extent_map_tree_init(&ei->extent_tree);
6692 extent_io_tree_init(&ei->io_tree, &inode->i_data);
6693 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
6694 mutex_init(&ei->log_mutex);
6695 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
6696 INIT_LIST_HEAD(&ei->i_orphan);
6697 INIT_LIST_HEAD(&ei->delalloc_inodes);
6698 INIT_LIST_HEAD(&ei->ordered_operations);
6699 RB_CLEAR_NODE(&ei->rb_node);
6704 static void btrfs_i_callback(struct rcu_head *head)
6706 struct inode *inode = container_of(head, struct inode, i_rcu);
6707 INIT_LIST_HEAD(&inode->i_dentry);
6708 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
6711 void btrfs_destroy_inode(struct inode *inode)
6713 struct btrfs_ordered_extent *ordered;
6714 struct btrfs_root *root = BTRFS_I(inode)->root;
6716 WARN_ON(!list_empty(&inode->i_dentry));
6717 WARN_ON(inode->i_data.nrpages);
6718 WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents));
6719 WARN_ON(atomic_read(&BTRFS_I(inode)->reserved_extents));
6722 * This can happen where we create an inode, but somebody else also
6723 * created the same inode and we need to destroy the one we already
6730 * Make sure we're properly removed from the ordered operation
6734 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
6735 spin_lock(&root->fs_info->ordered_extent_lock);
6736 list_del_init(&BTRFS_I(inode)->ordered_operations);
6737 spin_unlock(&root->fs_info->ordered_extent_lock);
6740 if (root == root->fs_info->tree_root) {
6741 struct btrfs_block_group_cache *block_group;
6743 block_group = btrfs_lookup_block_group(root->fs_info,
6744 BTRFS_I(inode)->block_group);
6745 if (block_group && block_group->inode == inode) {
6746 spin_lock(&block_group->lock);
6747 block_group->inode = NULL;
6748 spin_unlock(&block_group->lock);
6749 btrfs_put_block_group(block_group);
6750 } else if (block_group) {
6751 btrfs_put_block_group(block_group);
6755 spin_lock(&root->orphan_lock);
6756 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
6757 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
6758 (unsigned long long)btrfs_ino(inode));
6759 list_del_init(&BTRFS_I(inode)->i_orphan);
6761 spin_unlock(&root->orphan_lock);
6764 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
6768 printk(KERN_ERR "btrfs found ordered "
6769 "extent %llu %llu on inode cleanup\n",
6770 (unsigned long long)ordered->file_offset,
6771 (unsigned long long)ordered->len);
6772 btrfs_remove_ordered_extent(inode, ordered);
6773 btrfs_put_ordered_extent(ordered);
6774 btrfs_put_ordered_extent(ordered);
6777 inode_tree_del(inode);
6778 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
6780 btrfs_remove_delayed_node(inode);
6781 call_rcu(&inode->i_rcu, btrfs_i_callback);
6784 int btrfs_drop_inode(struct inode *inode)
6786 struct btrfs_root *root = BTRFS_I(inode)->root;
6788 if (btrfs_root_refs(&root->root_item) == 0 &&
6789 !is_free_space_inode(root, inode))
6792 return generic_drop_inode(inode);
6795 static void init_once(void *foo)
6797 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
6799 inode_init_once(&ei->vfs_inode);
6802 void btrfs_destroy_cachep(void)
6804 if (btrfs_inode_cachep)
6805 kmem_cache_destroy(btrfs_inode_cachep);
6806 if (btrfs_trans_handle_cachep)
6807 kmem_cache_destroy(btrfs_trans_handle_cachep);
6808 if (btrfs_transaction_cachep)
6809 kmem_cache_destroy(btrfs_transaction_cachep);
6810 if (btrfs_path_cachep)
6811 kmem_cache_destroy(btrfs_path_cachep);
6812 if (btrfs_free_space_cachep)
6813 kmem_cache_destroy(btrfs_free_space_cachep);
6816 int btrfs_init_cachep(void)
6818 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
6819 sizeof(struct btrfs_inode), 0,
6820 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
6821 if (!btrfs_inode_cachep)
6824 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
6825 sizeof(struct btrfs_trans_handle), 0,
6826 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6827 if (!btrfs_trans_handle_cachep)
6830 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
6831 sizeof(struct btrfs_transaction), 0,
6832 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6833 if (!btrfs_transaction_cachep)
6836 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
6837 sizeof(struct btrfs_path), 0,
6838 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6839 if (!btrfs_path_cachep)
6842 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
6843 sizeof(struct btrfs_free_space), 0,
6844 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6845 if (!btrfs_free_space_cachep)
6850 btrfs_destroy_cachep();
6854 static int btrfs_getattr(struct vfsmount *mnt,
6855 struct dentry *dentry, struct kstat *stat)
6857 struct inode *inode = dentry->d_inode;
6858 generic_fillattr(inode, stat);
6859 stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
6860 stat->blksize = PAGE_CACHE_SIZE;
6861 stat->blocks = (inode_get_bytes(inode) +
6862 BTRFS_I(inode)->delalloc_bytes) >> 9;
6867 * If a file is moved, it will inherit the cow and compression flags of the new
6870 static void fixup_inode_flags(struct inode *dir, struct inode *inode)
6872 struct btrfs_inode *b_dir = BTRFS_I(dir);
6873 struct btrfs_inode *b_inode = BTRFS_I(inode);
6875 if (b_dir->flags & BTRFS_INODE_NODATACOW)
6876 b_inode->flags |= BTRFS_INODE_NODATACOW;
6878 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
6880 if (b_dir->flags & BTRFS_INODE_COMPRESS)
6881 b_inode->flags |= BTRFS_INODE_COMPRESS;
6883 b_inode->flags &= ~BTRFS_INODE_COMPRESS;
6886 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
6887 struct inode *new_dir, struct dentry *new_dentry)
6889 struct btrfs_trans_handle *trans;
6890 struct btrfs_root *root = BTRFS_I(old_dir)->root;
6891 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
6892 struct inode *new_inode = new_dentry->d_inode;
6893 struct inode *old_inode = old_dentry->d_inode;
6894 struct timespec ctime = CURRENT_TIME;
6898 u64 old_ino = btrfs_ino(old_inode);
6900 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
6903 /* we only allow rename subvolume link between subvolumes */
6904 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
6907 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
6908 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
6911 if (S_ISDIR(old_inode->i_mode) && new_inode &&
6912 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
6915 * we're using rename to replace one file with another.
6916 * and the replacement file is large. Start IO on it now so
6917 * we don't add too much work to the end of the transaction
6919 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
6920 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
6921 filemap_flush(old_inode->i_mapping);
6923 /* close the racy window with snapshot create/destroy ioctl */
6924 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
6925 down_read(&root->fs_info->subvol_sem);
6927 * We want to reserve the absolute worst case amount of items. So if
6928 * both inodes are subvols and we need to unlink them then that would
6929 * require 4 item modifications, but if they are both normal inodes it
6930 * would require 5 item modifications, so we'll assume their normal
6931 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
6932 * should cover the worst case number of items we'll modify.
6934 trans = btrfs_start_transaction(root, 20);
6935 if (IS_ERR(trans)) {
6936 ret = PTR_ERR(trans);
6940 btrfs_set_trans_block_group(trans, new_dir);
6943 btrfs_record_root_in_trans(trans, dest);
6945 ret = btrfs_set_inode_index(new_dir, &index);
6949 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6950 /* force full log commit if subvolume involved. */
6951 root->fs_info->last_trans_log_full_commit = trans->transid;
6953 ret = btrfs_insert_inode_ref(trans, dest,
6954 new_dentry->d_name.name,
6955 new_dentry->d_name.len,
6957 btrfs_ino(new_dir), index);
6961 * this is an ugly little race, but the rename is required
6962 * to make sure that if we crash, the inode is either at the
6963 * old name or the new one. pinning the log transaction lets
6964 * us make sure we don't allow a log commit to come in after
6965 * we unlink the name but before we add the new name back in.
6967 btrfs_pin_log_trans(root);
6970 * make sure the inode gets flushed if it is replacing
6973 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
6974 btrfs_add_ordered_operation(trans, root, old_inode);
6976 old_dir->i_ctime = old_dir->i_mtime = ctime;
6977 new_dir->i_ctime = new_dir->i_mtime = ctime;
6978 old_inode->i_ctime = ctime;
6980 if (old_dentry->d_parent != new_dentry->d_parent)
6981 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
6983 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6984 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
6985 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
6986 old_dentry->d_name.name,
6987 old_dentry->d_name.len);
6989 ret = __btrfs_unlink_inode(trans, root, old_dir,
6990 old_dentry->d_inode,
6991 old_dentry->d_name.name,
6992 old_dentry->d_name.len);
6994 ret = btrfs_update_inode(trans, root, old_inode);
6999 new_inode->i_ctime = CURRENT_TIME;
7000 if (unlikely(btrfs_ino(new_inode) ==
7001 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
7002 root_objectid = BTRFS_I(new_inode)->location.objectid;
7003 ret = btrfs_unlink_subvol(trans, dest, new_dir,
7005 new_dentry->d_name.name,
7006 new_dentry->d_name.len);
7007 BUG_ON(new_inode->i_nlink == 0);
7009 ret = btrfs_unlink_inode(trans, dest, new_dir,
7010 new_dentry->d_inode,
7011 new_dentry->d_name.name,
7012 new_dentry->d_name.len);
7015 if (new_inode->i_nlink == 0) {
7016 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
7021 fixup_inode_flags(new_dir, old_inode);
7023 ret = btrfs_add_link(trans, new_dir, old_inode,
7024 new_dentry->d_name.name,
7025 new_dentry->d_name.len, 0, index);
7028 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
7029 struct dentry *parent = dget_parent(new_dentry);
7030 btrfs_log_new_name(trans, old_inode, old_dir, parent);
7032 btrfs_end_log_trans(root);
7035 btrfs_end_transaction_throttle(trans, root);
7037 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
7038 up_read(&root->fs_info->subvol_sem);
7044 * some fairly slow code that needs optimization. This walks the list
7045 * of all the inodes with pending delalloc and forces them to disk.
7047 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
7049 struct list_head *head = &root->fs_info->delalloc_inodes;
7050 struct btrfs_inode *binode;
7051 struct inode *inode;
7053 if (root->fs_info->sb->s_flags & MS_RDONLY)
7056 spin_lock(&root->fs_info->delalloc_lock);
7057 while (!list_empty(head)) {
7058 binode = list_entry(head->next, struct btrfs_inode,
7060 inode = igrab(&binode->vfs_inode);
7062 list_del_init(&binode->delalloc_inodes);
7063 spin_unlock(&root->fs_info->delalloc_lock);
7065 filemap_flush(inode->i_mapping);
7067 btrfs_add_delayed_iput(inode);
7072 spin_lock(&root->fs_info->delalloc_lock);
7074 spin_unlock(&root->fs_info->delalloc_lock);
7076 /* the filemap_flush will queue IO into the worker threads, but
7077 * we have to make sure the IO is actually started and that
7078 * ordered extents get created before we return
7080 atomic_inc(&root->fs_info->async_submit_draining);
7081 while (atomic_read(&root->fs_info->nr_async_submits) ||
7082 atomic_read(&root->fs_info->async_delalloc_pages)) {
7083 wait_event(root->fs_info->async_submit_wait,
7084 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
7085 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
7087 atomic_dec(&root->fs_info->async_submit_draining);
7091 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
7092 const char *symname)
7094 struct btrfs_trans_handle *trans;
7095 struct btrfs_root *root = BTRFS_I(dir)->root;
7096 struct btrfs_path *path;
7097 struct btrfs_key key;
7098 struct inode *inode = NULL;
7106 struct btrfs_file_extent_item *ei;
7107 struct extent_buffer *leaf;
7108 unsigned long nr = 0;
7110 name_len = strlen(symname) + 1;
7111 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
7112 return -ENAMETOOLONG;
7115 * 2 items for inode item and ref
7116 * 2 items for dir items
7117 * 1 item for xattr if selinux is on
7119 trans = btrfs_start_transaction(root, 5);
7121 return PTR_ERR(trans);
7123 btrfs_set_trans_block_group(trans, dir);
7125 err = btrfs_find_free_ino(root, &objectid);
7129 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
7130 dentry->d_name.len, btrfs_ino(dir), objectid,
7131 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO,
7133 if (IS_ERR(inode)) {
7134 err = PTR_ERR(inode);
7138 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
7144 btrfs_set_trans_block_group(trans, inode);
7145 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
7149 inode->i_mapping->a_ops = &btrfs_aops;
7150 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7151 inode->i_fop = &btrfs_file_operations;
7152 inode->i_op = &btrfs_file_inode_operations;
7153 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
7155 btrfs_update_inode_block_group(trans, inode);
7156 btrfs_update_inode_block_group(trans, dir);
7160 path = btrfs_alloc_path();
7162 key.objectid = btrfs_ino(inode);
7164 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
7165 datasize = btrfs_file_extent_calc_inline_size(name_len);
7166 err = btrfs_insert_empty_item(trans, root, path, &key,
7172 leaf = path->nodes[0];
7173 ei = btrfs_item_ptr(leaf, path->slots[0],
7174 struct btrfs_file_extent_item);
7175 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
7176 btrfs_set_file_extent_type(leaf, ei,
7177 BTRFS_FILE_EXTENT_INLINE);
7178 btrfs_set_file_extent_encryption(leaf, ei, 0);
7179 btrfs_set_file_extent_compression(leaf, ei, 0);
7180 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
7181 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
7183 ptr = btrfs_file_extent_inline_start(ei);
7184 write_extent_buffer(leaf, symname, ptr, name_len);
7185 btrfs_mark_buffer_dirty(leaf);
7186 btrfs_free_path(path);
7188 inode->i_op = &btrfs_symlink_inode_operations;
7189 inode->i_mapping->a_ops = &btrfs_symlink_aops;
7190 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7191 inode_set_bytes(inode, name_len);
7192 btrfs_i_size_write(inode, name_len - 1);
7193 err = btrfs_update_inode(trans, root, inode);
7198 nr = trans->blocks_used;
7199 btrfs_end_transaction_throttle(trans, root);
7201 inode_dec_link_count(inode);
7204 btrfs_btree_balance_dirty(root, nr);
7208 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
7209 u64 start, u64 num_bytes, u64 min_size,
7210 loff_t actual_len, u64 *alloc_hint,
7211 struct btrfs_trans_handle *trans)
7213 struct btrfs_root *root = BTRFS_I(inode)->root;
7214 struct btrfs_key ins;
7215 u64 cur_offset = start;
7218 bool own_trans = true;
7222 while (num_bytes > 0) {
7224 trans = btrfs_start_transaction(root, 3);
7225 if (IS_ERR(trans)) {
7226 ret = PTR_ERR(trans);
7231 ret = btrfs_reserve_extent(trans, root, num_bytes, min_size,
7232 0, *alloc_hint, (u64)-1, &ins, 1);
7235 btrfs_end_transaction(trans, root);
7239 ret = insert_reserved_file_extent(trans, inode,
7240 cur_offset, ins.objectid,
7241 ins.offset, ins.offset,
7242 ins.offset, 0, 0, 0,
7243 BTRFS_FILE_EXTENT_PREALLOC);
7245 btrfs_drop_extent_cache(inode, cur_offset,
7246 cur_offset + ins.offset -1, 0);
7248 num_bytes -= ins.offset;
7249 cur_offset += ins.offset;
7250 *alloc_hint = ins.objectid + ins.offset;
7252 inode->i_ctime = CURRENT_TIME;
7253 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
7254 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
7255 (actual_len > inode->i_size) &&
7256 (cur_offset > inode->i_size)) {
7257 if (cur_offset > actual_len)
7258 i_size = actual_len;
7260 i_size = cur_offset;
7261 i_size_write(inode, i_size);
7262 btrfs_ordered_update_i_size(inode, i_size, NULL);
7265 ret = btrfs_update_inode(trans, root, inode);
7269 btrfs_end_transaction(trans, root);
7274 int btrfs_prealloc_file_range(struct inode *inode, int mode,
7275 u64 start, u64 num_bytes, u64 min_size,
7276 loff_t actual_len, u64 *alloc_hint)
7278 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7279 min_size, actual_len, alloc_hint,
7283 int btrfs_prealloc_file_range_trans(struct inode *inode,
7284 struct btrfs_trans_handle *trans, int mode,
7285 u64 start, u64 num_bytes, u64 min_size,
7286 loff_t actual_len, u64 *alloc_hint)
7288 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7289 min_size, actual_len, alloc_hint, trans);
7292 static int btrfs_set_page_dirty(struct page *page)
7294 return __set_page_dirty_nobuffers(page);
7297 static int btrfs_permission(struct inode *inode, int mask, unsigned int flags)
7299 struct btrfs_root *root = BTRFS_I(inode)->root;
7301 if (btrfs_root_readonly(root) && (mask & MAY_WRITE))
7303 if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE))
7305 return generic_permission(inode, mask, flags, btrfs_check_acl);
7308 static const struct inode_operations btrfs_dir_inode_operations = {
7309 .getattr = btrfs_getattr,
7310 .lookup = btrfs_lookup,
7311 .create = btrfs_create,
7312 .unlink = btrfs_unlink,
7314 .mkdir = btrfs_mkdir,
7315 .rmdir = btrfs_rmdir,
7316 .rename = btrfs_rename,
7317 .symlink = btrfs_symlink,
7318 .setattr = btrfs_setattr,
7319 .mknod = btrfs_mknod,
7320 .setxattr = btrfs_setxattr,
7321 .getxattr = btrfs_getxattr,
7322 .listxattr = btrfs_listxattr,
7323 .removexattr = btrfs_removexattr,
7324 .permission = btrfs_permission,
7326 static const struct inode_operations btrfs_dir_ro_inode_operations = {
7327 .lookup = btrfs_lookup,
7328 .permission = btrfs_permission,
7331 static const struct file_operations btrfs_dir_file_operations = {
7332 .llseek = generic_file_llseek,
7333 .read = generic_read_dir,
7334 .readdir = btrfs_real_readdir,
7335 .unlocked_ioctl = btrfs_ioctl,
7336 #ifdef CONFIG_COMPAT
7337 .compat_ioctl = btrfs_ioctl,
7339 .release = btrfs_release_file,
7340 .fsync = btrfs_sync_file,
7343 static struct extent_io_ops btrfs_extent_io_ops = {
7344 .fill_delalloc = run_delalloc_range,
7345 .submit_bio_hook = btrfs_submit_bio_hook,
7346 .merge_bio_hook = btrfs_merge_bio_hook,
7347 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
7348 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
7349 .writepage_start_hook = btrfs_writepage_start_hook,
7350 .readpage_io_failed_hook = btrfs_io_failed_hook,
7351 .set_bit_hook = btrfs_set_bit_hook,
7352 .clear_bit_hook = btrfs_clear_bit_hook,
7353 .merge_extent_hook = btrfs_merge_extent_hook,
7354 .split_extent_hook = btrfs_split_extent_hook,
7358 * btrfs doesn't support the bmap operation because swapfiles
7359 * use bmap to make a mapping of extents in the file. They assume
7360 * these extents won't change over the life of the file and they
7361 * use the bmap result to do IO directly to the drive.
7363 * the btrfs bmap call would return logical addresses that aren't
7364 * suitable for IO and they also will change frequently as COW
7365 * operations happen. So, swapfile + btrfs == corruption.
7367 * For now we're avoiding this by dropping bmap.
7369 static const struct address_space_operations btrfs_aops = {
7370 .readpage = btrfs_readpage,
7371 .writepage = btrfs_writepage,
7372 .writepages = btrfs_writepages,
7373 .readpages = btrfs_readpages,
7374 .direct_IO = btrfs_direct_IO,
7375 .invalidatepage = btrfs_invalidatepage,
7376 .releasepage = btrfs_releasepage,
7377 .set_page_dirty = btrfs_set_page_dirty,
7378 .error_remove_page = generic_error_remove_page,
7381 static const struct address_space_operations btrfs_symlink_aops = {
7382 .readpage = btrfs_readpage,
7383 .writepage = btrfs_writepage,
7384 .invalidatepage = btrfs_invalidatepage,
7385 .releasepage = btrfs_releasepage,
7388 static const struct inode_operations btrfs_file_inode_operations = {
7389 .getattr = btrfs_getattr,
7390 .setattr = btrfs_setattr,
7391 .setxattr = btrfs_setxattr,
7392 .getxattr = btrfs_getxattr,
7393 .listxattr = btrfs_listxattr,
7394 .removexattr = btrfs_removexattr,
7395 .permission = btrfs_permission,
7396 .fiemap = btrfs_fiemap,
7398 static const struct inode_operations btrfs_special_inode_operations = {
7399 .getattr = btrfs_getattr,
7400 .setattr = btrfs_setattr,
7401 .permission = btrfs_permission,
7402 .setxattr = btrfs_setxattr,
7403 .getxattr = btrfs_getxattr,
7404 .listxattr = btrfs_listxattr,
7405 .removexattr = btrfs_removexattr,
7407 static const struct inode_operations btrfs_symlink_inode_operations = {
7408 .readlink = generic_readlink,
7409 .follow_link = page_follow_link_light,
7410 .put_link = page_put_link,
7411 .getattr = btrfs_getattr,
7412 .permission = btrfs_permission,
7413 .setxattr = btrfs_setxattr,
7414 .getxattr = btrfs_getxattr,
7415 .listxattr = btrfs_listxattr,
7416 .removexattr = btrfs_removexattr,
7419 const struct dentry_operations btrfs_dentry_operations = {
7420 .d_delete = btrfs_dentry_delete,