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;
142 key.objectid = btrfs_ino(inode);
144 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
145 datasize = btrfs_file_extent_calc_inline_size(cur_size);
147 inode_add_bytes(inode, size);
148 ret = btrfs_insert_empty_item(trans, root, path, &key,
155 leaf = path->nodes[0];
156 ei = btrfs_item_ptr(leaf, path->slots[0],
157 struct btrfs_file_extent_item);
158 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
159 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
160 btrfs_set_file_extent_encryption(leaf, ei, 0);
161 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
162 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
163 ptr = btrfs_file_extent_inline_start(ei);
165 if (compress_type != BTRFS_COMPRESS_NONE) {
168 while (compressed_size > 0) {
169 cpage = compressed_pages[i];
170 cur_size = min_t(unsigned long, compressed_size,
173 kaddr = kmap_atomic(cpage, KM_USER0);
174 write_extent_buffer(leaf, kaddr, ptr, cur_size);
175 kunmap_atomic(kaddr, KM_USER0);
179 compressed_size -= cur_size;
181 btrfs_set_file_extent_compression(leaf, ei,
184 page = find_get_page(inode->i_mapping,
185 start >> PAGE_CACHE_SHIFT);
186 btrfs_set_file_extent_compression(leaf, ei, 0);
187 kaddr = kmap_atomic(page, KM_USER0);
188 offset = start & (PAGE_CACHE_SIZE - 1);
189 write_extent_buffer(leaf, kaddr + offset, ptr, size);
190 kunmap_atomic(kaddr, KM_USER0);
191 page_cache_release(page);
193 btrfs_mark_buffer_dirty(leaf);
194 btrfs_free_path(path);
197 * we're an inline extent, so nobody can
198 * extend the file past i_size without locking
199 * a page we already have locked.
201 * We must do any isize and inode updates
202 * before we unlock the pages. Otherwise we
203 * could end up racing with unlink.
205 BTRFS_I(inode)->disk_i_size = inode->i_size;
206 btrfs_update_inode(trans, root, inode);
210 btrfs_free_path(path);
216 * conditionally insert an inline extent into the file. This
217 * does the checks required to make sure the data is small enough
218 * to fit as an inline extent.
220 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
221 struct btrfs_root *root,
222 struct inode *inode, u64 start, u64 end,
223 size_t compressed_size, int compress_type,
224 struct page **compressed_pages)
226 u64 isize = i_size_read(inode);
227 u64 actual_end = min(end + 1, isize);
228 u64 inline_len = actual_end - start;
229 u64 aligned_end = (end + root->sectorsize - 1) &
230 ~((u64)root->sectorsize - 1);
232 u64 data_len = inline_len;
236 data_len = compressed_size;
239 actual_end >= PAGE_CACHE_SIZE ||
240 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
242 (actual_end & (root->sectorsize - 1)) == 0) ||
244 data_len > root->fs_info->max_inline) {
248 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
252 if (isize > actual_end)
253 inline_len = min_t(u64, isize, actual_end);
254 ret = insert_inline_extent(trans, root, inode, start,
255 inline_len, compressed_size,
256 compress_type, compressed_pages);
258 btrfs_delalloc_release_metadata(inode, end + 1 - start);
259 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
263 struct async_extent {
268 unsigned long nr_pages;
270 struct list_head list;
275 struct btrfs_root *root;
276 struct page *locked_page;
279 struct list_head extents;
280 struct btrfs_work work;
283 static noinline int add_async_extent(struct async_cow *cow,
284 u64 start, u64 ram_size,
287 unsigned long nr_pages,
290 struct async_extent *async_extent;
292 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
293 BUG_ON(!async_extent);
294 async_extent->start = start;
295 async_extent->ram_size = ram_size;
296 async_extent->compressed_size = compressed_size;
297 async_extent->pages = pages;
298 async_extent->nr_pages = nr_pages;
299 async_extent->compress_type = compress_type;
300 list_add_tail(&async_extent->list, &cow->extents);
305 * we create compressed extents in two phases. The first
306 * phase compresses a range of pages that have already been
307 * locked (both pages and state bits are locked).
309 * This is done inside an ordered work queue, and the compression
310 * is spread across many cpus. The actual IO submission is step
311 * two, and the ordered work queue takes care of making sure that
312 * happens in the same order things were put onto the queue by
313 * writepages and friends.
315 * If this code finds it can't get good compression, it puts an
316 * entry onto the work queue to write the uncompressed bytes. This
317 * makes sure that both compressed inodes and uncompressed inodes
318 * are written in the same order that pdflush sent them down.
320 static noinline int compress_file_range(struct inode *inode,
321 struct page *locked_page,
323 struct async_cow *async_cow,
326 struct btrfs_root *root = BTRFS_I(inode)->root;
327 struct btrfs_trans_handle *trans;
329 u64 blocksize = root->sectorsize;
331 u64 isize = i_size_read(inode);
333 struct page **pages = NULL;
334 unsigned long nr_pages;
335 unsigned long nr_pages_ret = 0;
336 unsigned long total_compressed = 0;
337 unsigned long total_in = 0;
338 unsigned long max_compressed = 128 * 1024;
339 unsigned long max_uncompressed = 128 * 1024;
342 int compress_type = root->fs_info->compress_type;
344 /* if this is a small write inside eof, kick off a defragbot */
345 if (end <= BTRFS_I(inode)->disk_i_size && (end - start + 1) < 16 * 1024)
346 btrfs_add_inode_defrag(NULL, inode);
348 actual_end = min_t(u64, isize, end + 1);
351 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
352 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
355 * we don't want to send crud past the end of i_size through
356 * compression, that's just a waste of CPU time. So, if the
357 * end of the file is before the start of our current
358 * requested range of bytes, we bail out to the uncompressed
359 * cleanup code that can deal with all of this.
361 * It isn't really the fastest way to fix things, but this is a
362 * very uncommon corner.
364 if (actual_end <= start)
365 goto cleanup_and_bail_uncompressed;
367 total_compressed = actual_end - start;
369 /* we want to make sure that amount of ram required to uncompress
370 * an extent is reasonable, so we limit the total size in ram
371 * of a compressed extent to 128k. This is a crucial number
372 * because it also controls how easily we can spread reads across
373 * cpus for decompression.
375 * We also want to make sure the amount of IO required to do
376 * a random read is reasonably small, so we limit the size of
377 * a compressed extent to 128k.
379 total_compressed = min(total_compressed, max_uncompressed);
380 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
381 num_bytes = max(blocksize, num_bytes);
386 * we do compression for mount -o compress and when the
387 * inode has not been flagged as nocompress. This flag can
388 * change at any time if we discover bad compression ratios.
390 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
391 (btrfs_test_opt(root, COMPRESS) ||
392 (BTRFS_I(inode)->force_compress) ||
393 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
395 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
398 if (BTRFS_I(inode)->force_compress)
399 compress_type = BTRFS_I(inode)->force_compress;
401 ret = btrfs_compress_pages(compress_type,
402 inode->i_mapping, start,
403 total_compressed, pages,
404 nr_pages, &nr_pages_ret,
410 unsigned long offset = total_compressed &
411 (PAGE_CACHE_SIZE - 1);
412 struct page *page = pages[nr_pages_ret - 1];
415 /* zero the tail end of the last page, we might be
416 * sending it down to disk
419 kaddr = kmap_atomic(page, KM_USER0);
420 memset(kaddr + offset, 0,
421 PAGE_CACHE_SIZE - offset);
422 kunmap_atomic(kaddr, KM_USER0);
428 trans = btrfs_join_transaction(root);
429 BUG_ON(IS_ERR(trans));
430 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
432 /* lets try to make an inline extent */
433 if (ret || total_in < (actual_end - start)) {
434 /* we didn't compress the entire range, try
435 * to make an uncompressed inline extent.
437 ret = cow_file_range_inline(trans, root, inode,
438 start, end, 0, 0, NULL);
440 /* try making a compressed inline extent */
441 ret = cow_file_range_inline(trans, root, inode,
444 compress_type, pages);
448 * inline extent creation worked, we don't need
449 * to create any more async work items. Unlock
450 * and free up our temp pages.
452 extent_clear_unlock_delalloc(inode,
453 &BTRFS_I(inode)->io_tree,
455 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
456 EXTENT_CLEAR_DELALLOC |
457 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
459 btrfs_end_transaction(trans, root);
462 btrfs_end_transaction(trans, root);
467 * we aren't doing an inline extent round the compressed size
468 * up to a block size boundary so the allocator does sane
471 total_compressed = (total_compressed + blocksize - 1) &
475 * one last check to make sure the compression is really a
476 * win, compare the page count read with the blocks on disk
478 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
479 ~(PAGE_CACHE_SIZE - 1);
480 if (total_compressed >= total_in) {
483 num_bytes = total_in;
486 if (!will_compress && pages) {
488 * the compression code ran but failed to make things smaller,
489 * free any pages it allocated and our page pointer array
491 for (i = 0; i < nr_pages_ret; i++) {
492 WARN_ON(pages[i]->mapping);
493 page_cache_release(pages[i]);
497 total_compressed = 0;
500 /* flag the file so we don't compress in the future */
501 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
502 !(BTRFS_I(inode)->force_compress)) {
503 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
509 /* the async work queues will take care of doing actual
510 * allocation on disk for these compressed pages,
511 * and will submit them to the elevator.
513 add_async_extent(async_cow, start, num_bytes,
514 total_compressed, pages, nr_pages_ret,
517 if (start + num_bytes < end) {
524 cleanup_and_bail_uncompressed:
526 * No compression, but we still need to write the pages in
527 * the file we've been given so far. redirty the locked
528 * page if it corresponds to our extent and set things up
529 * for the async work queue to run cow_file_range to do
530 * the normal delalloc dance
532 if (page_offset(locked_page) >= start &&
533 page_offset(locked_page) <= end) {
534 __set_page_dirty_nobuffers(locked_page);
535 /* unlocked later on in the async handlers */
537 add_async_extent(async_cow, start, end - start + 1,
538 0, NULL, 0, BTRFS_COMPRESS_NONE);
546 for (i = 0; i < nr_pages_ret; i++) {
547 WARN_ON(pages[i]->mapping);
548 page_cache_release(pages[i]);
556 * phase two of compressed writeback. This is the ordered portion
557 * of the code, which only gets called in the order the work was
558 * queued. We walk all the async extents created by compress_file_range
559 * and send them down to the disk.
561 static noinline int submit_compressed_extents(struct inode *inode,
562 struct async_cow *async_cow)
564 struct async_extent *async_extent;
566 struct btrfs_trans_handle *trans;
567 struct btrfs_key ins;
568 struct extent_map *em;
569 struct btrfs_root *root = BTRFS_I(inode)->root;
570 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
571 struct extent_io_tree *io_tree;
574 if (list_empty(&async_cow->extents))
578 while (!list_empty(&async_cow->extents)) {
579 async_extent = list_entry(async_cow->extents.next,
580 struct async_extent, list);
581 list_del(&async_extent->list);
583 io_tree = &BTRFS_I(inode)->io_tree;
586 /* did the compression code fall back to uncompressed IO? */
587 if (!async_extent->pages) {
588 int page_started = 0;
589 unsigned long nr_written = 0;
591 lock_extent(io_tree, async_extent->start,
592 async_extent->start +
593 async_extent->ram_size - 1, GFP_NOFS);
595 /* allocate blocks */
596 ret = cow_file_range(inode, async_cow->locked_page,
598 async_extent->start +
599 async_extent->ram_size - 1,
600 &page_started, &nr_written, 0);
603 * if page_started, cow_file_range inserted an
604 * inline extent and took care of all the unlocking
605 * and IO for us. Otherwise, we need to submit
606 * all those pages down to the drive.
608 if (!page_started && !ret)
609 extent_write_locked_range(io_tree,
610 inode, async_extent->start,
611 async_extent->start +
612 async_extent->ram_size - 1,
620 lock_extent(io_tree, async_extent->start,
621 async_extent->start + async_extent->ram_size - 1,
624 trans = btrfs_join_transaction(root);
625 BUG_ON(IS_ERR(trans));
626 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
627 ret = btrfs_reserve_extent(trans, root,
628 async_extent->compressed_size,
629 async_extent->compressed_size,
632 btrfs_end_transaction(trans, root);
636 for (i = 0; i < async_extent->nr_pages; i++) {
637 WARN_ON(async_extent->pages[i]->mapping);
638 page_cache_release(async_extent->pages[i]);
640 kfree(async_extent->pages);
641 async_extent->nr_pages = 0;
642 async_extent->pages = NULL;
643 unlock_extent(io_tree, async_extent->start,
644 async_extent->start +
645 async_extent->ram_size - 1, GFP_NOFS);
650 * here we're doing allocation and writeback of the
653 btrfs_drop_extent_cache(inode, async_extent->start,
654 async_extent->start +
655 async_extent->ram_size - 1, 0);
657 em = alloc_extent_map();
659 em->start = async_extent->start;
660 em->len = async_extent->ram_size;
661 em->orig_start = em->start;
663 em->block_start = ins.objectid;
664 em->block_len = ins.offset;
665 em->bdev = root->fs_info->fs_devices->latest_bdev;
666 em->compress_type = async_extent->compress_type;
667 set_bit(EXTENT_FLAG_PINNED, &em->flags);
668 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
671 write_lock(&em_tree->lock);
672 ret = add_extent_mapping(em_tree, em);
673 write_unlock(&em_tree->lock);
674 if (ret != -EEXIST) {
678 btrfs_drop_extent_cache(inode, async_extent->start,
679 async_extent->start +
680 async_extent->ram_size - 1, 0);
683 ret = btrfs_add_ordered_extent_compress(inode,
686 async_extent->ram_size,
688 BTRFS_ORDERED_COMPRESSED,
689 async_extent->compress_type);
693 * clear dirty, set writeback and unlock the pages.
695 extent_clear_unlock_delalloc(inode,
696 &BTRFS_I(inode)->io_tree,
698 async_extent->start +
699 async_extent->ram_size - 1,
700 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
701 EXTENT_CLEAR_UNLOCK |
702 EXTENT_CLEAR_DELALLOC |
703 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
705 ret = btrfs_submit_compressed_write(inode,
707 async_extent->ram_size,
709 ins.offset, async_extent->pages,
710 async_extent->nr_pages);
713 alloc_hint = ins.objectid + ins.offset;
721 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
724 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
725 struct extent_map *em;
728 read_lock(&em_tree->lock);
729 em = search_extent_mapping(em_tree, start, num_bytes);
732 * if block start isn't an actual block number then find the
733 * first block in this inode and use that as a hint. If that
734 * block is also bogus then just don't worry about it.
736 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
738 em = search_extent_mapping(em_tree, 0, 0);
739 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
740 alloc_hint = em->block_start;
744 alloc_hint = em->block_start;
748 read_unlock(&em_tree->lock);
753 static inline bool is_free_space_inode(struct btrfs_root *root,
756 if (root == root->fs_info->tree_root ||
757 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
763 * when extent_io.c finds a delayed allocation range in the file,
764 * the call backs end up in this code. The basic idea is to
765 * allocate extents on disk for the range, and create ordered data structs
766 * in ram to track those extents.
768 * locked_page is the page that writepage had locked already. We use
769 * it to make sure we don't do extra locks or unlocks.
771 * *page_started is set to one if we unlock locked_page and do everything
772 * required to start IO on it. It may be clean and already done with
775 static noinline int cow_file_range(struct inode *inode,
776 struct page *locked_page,
777 u64 start, u64 end, int *page_started,
778 unsigned long *nr_written,
781 struct btrfs_root *root = BTRFS_I(inode)->root;
782 struct btrfs_trans_handle *trans;
785 unsigned long ram_size;
788 u64 blocksize = root->sectorsize;
789 struct btrfs_key ins;
790 struct extent_map *em;
791 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
794 BUG_ON(is_free_space_inode(root, inode));
795 trans = btrfs_join_transaction(root);
796 BUG_ON(IS_ERR(trans));
797 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
799 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
800 num_bytes = max(blocksize, num_bytes);
801 disk_num_bytes = num_bytes;
804 /* if this is a small write inside eof, kick off defrag */
805 if (end <= BTRFS_I(inode)->disk_i_size && num_bytes < 64 * 1024)
806 btrfs_add_inode_defrag(trans, inode);
809 /* lets try to make an inline extent */
810 ret = cow_file_range_inline(trans, root, inode,
811 start, end, 0, 0, NULL);
813 extent_clear_unlock_delalloc(inode,
814 &BTRFS_I(inode)->io_tree,
816 EXTENT_CLEAR_UNLOCK_PAGE |
817 EXTENT_CLEAR_UNLOCK |
818 EXTENT_CLEAR_DELALLOC |
820 EXTENT_SET_WRITEBACK |
821 EXTENT_END_WRITEBACK);
823 *nr_written = *nr_written +
824 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
831 BUG_ON(disk_num_bytes >
832 btrfs_super_total_bytes(&root->fs_info->super_copy));
834 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
835 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
837 while (disk_num_bytes > 0) {
840 cur_alloc_size = disk_num_bytes;
841 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
842 root->sectorsize, 0, alloc_hint,
846 em = alloc_extent_map();
849 em->orig_start = em->start;
850 ram_size = ins.offset;
851 em->len = ins.offset;
853 em->block_start = ins.objectid;
854 em->block_len = ins.offset;
855 em->bdev = root->fs_info->fs_devices->latest_bdev;
856 set_bit(EXTENT_FLAG_PINNED, &em->flags);
859 write_lock(&em_tree->lock);
860 ret = add_extent_mapping(em_tree, em);
861 write_unlock(&em_tree->lock);
862 if (ret != -EEXIST) {
866 btrfs_drop_extent_cache(inode, start,
867 start + ram_size - 1, 0);
870 cur_alloc_size = ins.offset;
871 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
872 ram_size, cur_alloc_size, 0);
875 if (root->root_key.objectid ==
876 BTRFS_DATA_RELOC_TREE_OBJECTID) {
877 ret = btrfs_reloc_clone_csums(inode, start,
882 if (disk_num_bytes < cur_alloc_size)
885 /* we're not doing compressed IO, don't unlock the first
886 * page (which the caller expects to stay locked), don't
887 * clear any dirty bits and don't set any writeback bits
889 * Do set the Private2 bit so we know this page was properly
890 * setup for writepage
892 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
893 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
896 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
897 start, start + ram_size - 1,
899 disk_num_bytes -= cur_alloc_size;
900 num_bytes -= cur_alloc_size;
901 alloc_hint = ins.objectid + ins.offset;
902 start += cur_alloc_size;
906 btrfs_end_transaction(trans, root);
912 * work queue call back to started compression on a file and pages
914 static noinline void async_cow_start(struct btrfs_work *work)
916 struct async_cow *async_cow;
918 async_cow = container_of(work, struct async_cow, work);
920 compress_file_range(async_cow->inode, async_cow->locked_page,
921 async_cow->start, async_cow->end, async_cow,
924 async_cow->inode = NULL;
928 * work queue call back to submit previously compressed pages
930 static noinline void async_cow_submit(struct btrfs_work *work)
932 struct async_cow *async_cow;
933 struct btrfs_root *root;
934 unsigned long nr_pages;
936 async_cow = container_of(work, struct async_cow, work);
938 root = async_cow->root;
939 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
942 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
944 if (atomic_read(&root->fs_info->async_delalloc_pages) <
946 waitqueue_active(&root->fs_info->async_submit_wait))
947 wake_up(&root->fs_info->async_submit_wait);
949 if (async_cow->inode)
950 submit_compressed_extents(async_cow->inode, async_cow);
953 static noinline void async_cow_free(struct btrfs_work *work)
955 struct async_cow *async_cow;
956 async_cow = container_of(work, struct async_cow, work);
960 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
961 u64 start, u64 end, int *page_started,
962 unsigned long *nr_written)
964 struct async_cow *async_cow;
965 struct btrfs_root *root = BTRFS_I(inode)->root;
966 unsigned long nr_pages;
968 int limit = 10 * 1024 * 1042;
970 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
971 1, 0, NULL, GFP_NOFS);
972 while (start < end) {
973 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
975 async_cow->inode = inode;
976 async_cow->root = root;
977 async_cow->locked_page = locked_page;
978 async_cow->start = start;
980 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
983 cur_end = min(end, start + 512 * 1024 - 1);
985 async_cow->end = cur_end;
986 INIT_LIST_HEAD(&async_cow->extents);
988 async_cow->work.func = async_cow_start;
989 async_cow->work.ordered_func = async_cow_submit;
990 async_cow->work.ordered_free = async_cow_free;
991 async_cow->work.flags = 0;
993 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
995 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
997 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1000 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1001 wait_event(root->fs_info->async_submit_wait,
1002 (atomic_read(&root->fs_info->async_delalloc_pages) <
1006 while (atomic_read(&root->fs_info->async_submit_draining) &&
1007 atomic_read(&root->fs_info->async_delalloc_pages)) {
1008 wait_event(root->fs_info->async_submit_wait,
1009 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1013 *nr_written += nr_pages;
1014 start = cur_end + 1;
1020 static noinline int csum_exist_in_range(struct btrfs_root *root,
1021 u64 bytenr, u64 num_bytes)
1024 struct btrfs_ordered_sum *sums;
1027 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1028 bytenr + num_bytes - 1, &list, 0);
1029 if (ret == 0 && list_empty(&list))
1032 while (!list_empty(&list)) {
1033 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1034 list_del(&sums->list);
1041 * when nowcow writeback call back. This checks for snapshots or COW copies
1042 * of the extents that exist in the file, and COWs the file as required.
1044 * If no cow copies or snapshots exist, we write directly to the existing
1047 static noinline int run_delalloc_nocow(struct inode *inode,
1048 struct page *locked_page,
1049 u64 start, u64 end, int *page_started, int force,
1050 unsigned long *nr_written)
1052 struct btrfs_root *root = BTRFS_I(inode)->root;
1053 struct btrfs_trans_handle *trans;
1054 struct extent_buffer *leaf;
1055 struct btrfs_path *path;
1056 struct btrfs_file_extent_item *fi;
1057 struct btrfs_key found_key;
1070 u64 ino = btrfs_ino(inode);
1072 path = btrfs_alloc_path();
1075 nolock = is_free_space_inode(root, inode);
1078 trans = btrfs_join_transaction_nolock(root);
1080 trans = btrfs_join_transaction(root);
1082 BUG_ON(IS_ERR(trans));
1083 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1085 cow_start = (u64)-1;
1088 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1091 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1092 leaf = path->nodes[0];
1093 btrfs_item_key_to_cpu(leaf, &found_key,
1094 path->slots[0] - 1);
1095 if (found_key.objectid == ino &&
1096 found_key.type == BTRFS_EXTENT_DATA_KEY)
1101 leaf = path->nodes[0];
1102 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1103 ret = btrfs_next_leaf(root, path);
1108 leaf = path->nodes[0];
1114 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1116 if (found_key.objectid > ino ||
1117 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1118 found_key.offset > end)
1121 if (found_key.offset > cur_offset) {
1122 extent_end = found_key.offset;
1127 fi = btrfs_item_ptr(leaf, path->slots[0],
1128 struct btrfs_file_extent_item);
1129 extent_type = btrfs_file_extent_type(leaf, fi);
1131 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1132 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1133 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1134 extent_offset = btrfs_file_extent_offset(leaf, fi);
1135 extent_end = found_key.offset +
1136 btrfs_file_extent_num_bytes(leaf, fi);
1137 if (extent_end <= start) {
1141 if (disk_bytenr == 0)
1143 if (btrfs_file_extent_compression(leaf, fi) ||
1144 btrfs_file_extent_encryption(leaf, fi) ||
1145 btrfs_file_extent_other_encoding(leaf, fi))
1147 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1149 if (btrfs_extent_readonly(root, disk_bytenr))
1151 if (btrfs_cross_ref_exist(trans, root, ino,
1153 extent_offset, disk_bytenr))
1155 disk_bytenr += extent_offset;
1156 disk_bytenr += cur_offset - found_key.offset;
1157 num_bytes = min(end + 1, extent_end) - cur_offset;
1159 * force cow if csum exists in the range.
1160 * this ensure that csum for a given extent are
1161 * either valid or do not exist.
1163 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1166 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1167 extent_end = found_key.offset +
1168 btrfs_file_extent_inline_len(leaf, fi);
1169 extent_end = ALIGN(extent_end, root->sectorsize);
1174 if (extent_end <= start) {
1179 if (cow_start == (u64)-1)
1180 cow_start = cur_offset;
1181 cur_offset = extent_end;
1182 if (cur_offset > end)
1188 btrfs_release_path(path);
1189 if (cow_start != (u64)-1) {
1190 ret = cow_file_range(inode, locked_page, cow_start,
1191 found_key.offset - 1, page_started,
1194 cow_start = (u64)-1;
1197 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1198 struct extent_map *em;
1199 struct extent_map_tree *em_tree;
1200 em_tree = &BTRFS_I(inode)->extent_tree;
1201 em = alloc_extent_map();
1203 em->start = cur_offset;
1204 em->orig_start = em->start;
1205 em->len = num_bytes;
1206 em->block_len = num_bytes;
1207 em->block_start = disk_bytenr;
1208 em->bdev = root->fs_info->fs_devices->latest_bdev;
1209 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1211 write_lock(&em_tree->lock);
1212 ret = add_extent_mapping(em_tree, em);
1213 write_unlock(&em_tree->lock);
1214 if (ret != -EEXIST) {
1215 free_extent_map(em);
1218 btrfs_drop_extent_cache(inode, em->start,
1219 em->start + em->len - 1, 0);
1221 type = BTRFS_ORDERED_PREALLOC;
1223 type = BTRFS_ORDERED_NOCOW;
1226 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1227 num_bytes, num_bytes, type);
1230 if (root->root_key.objectid ==
1231 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1232 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1237 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1238 cur_offset, cur_offset + num_bytes - 1,
1239 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1240 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1241 EXTENT_SET_PRIVATE2);
1242 cur_offset = extent_end;
1243 if (cur_offset > end)
1246 btrfs_release_path(path);
1248 if (cur_offset <= end && cow_start == (u64)-1)
1249 cow_start = cur_offset;
1250 if (cow_start != (u64)-1) {
1251 ret = cow_file_range(inode, locked_page, cow_start, end,
1252 page_started, nr_written, 1);
1257 ret = btrfs_end_transaction_nolock(trans, root);
1260 ret = btrfs_end_transaction(trans, root);
1263 btrfs_free_path(path);
1268 * extent_io.c call back to do delayed allocation processing
1270 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1271 u64 start, u64 end, int *page_started,
1272 unsigned long *nr_written)
1275 struct btrfs_root *root = BTRFS_I(inode)->root;
1277 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1278 ret = run_delalloc_nocow(inode, locked_page, start, end,
1279 page_started, 1, nr_written);
1280 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1281 ret = run_delalloc_nocow(inode, locked_page, start, end,
1282 page_started, 0, nr_written);
1283 else if (!btrfs_test_opt(root, COMPRESS) &&
1284 !(BTRFS_I(inode)->force_compress) &&
1285 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
1286 ret = cow_file_range(inode, locked_page, start, end,
1287 page_started, nr_written, 1);
1289 ret = cow_file_range_async(inode, locked_page, start, end,
1290 page_started, nr_written);
1294 static int btrfs_split_extent_hook(struct inode *inode,
1295 struct extent_state *orig, u64 split)
1297 /* not delalloc, ignore it */
1298 if (!(orig->state & EXTENT_DELALLOC))
1301 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
1306 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1307 * extents so we can keep track of new extents that are just merged onto old
1308 * extents, such as when we are doing sequential writes, so we can properly
1309 * account for the metadata space we'll need.
1311 static int btrfs_merge_extent_hook(struct inode *inode,
1312 struct extent_state *new,
1313 struct extent_state *other)
1315 /* not delalloc, ignore it */
1316 if (!(other->state & EXTENT_DELALLOC))
1319 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
1324 * extent_io.c set_bit_hook, used to track delayed allocation
1325 * bytes in this file, and to maintain the list of inodes that
1326 * have pending delalloc work to be done.
1328 static int btrfs_set_bit_hook(struct inode *inode,
1329 struct extent_state *state, int *bits)
1333 * set_bit and clear bit hooks normally require _irqsave/restore
1334 * but in this case, we are only testing for the DELALLOC
1335 * bit, which is only set or cleared with irqs on
1337 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1338 struct btrfs_root *root = BTRFS_I(inode)->root;
1339 u64 len = state->end + 1 - state->start;
1340 bool do_list = !is_free_space_inode(root, inode);
1342 if (*bits & EXTENT_FIRST_DELALLOC)
1343 *bits &= ~EXTENT_FIRST_DELALLOC;
1345 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
1347 spin_lock(&root->fs_info->delalloc_lock);
1348 BTRFS_I(inode)->delalloc_bytes += len;
1349 root->fs_info->delalloc_bytes += len;
1350 if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1351 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1352 &root->fs_info->delalloc_inodes);
1354 spin_unlock(&root->fs_info->delalloc_lock);
1360 * extent_io.c clear_bit_hook, see set_bit_hook for why
1362 static int btrfs_clear_bit_hook(struct inode *inode,
1363 struct extent_state *state, int *bits)
1366 * set_bit and clear bit hooks normally require _irqsave/restore
1367 * but in this case, we are only testing for the DELALLOC
1368 * bit, which is only set or cleared with irqs on
1370 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1371 struct btrfs_root *root = BTRFS_I(inode)->root;
1372 u64 len = state->end + 1 - state->start;
1373 bool do_list = !is_free_space_inode(root, inode);
1375 if (*bits & EXTENT_FIRST_DELALLOC)
1376 *bits &= ~EXTENT_FIRST_DELALLOC;
1377 else if (!(*bits & EXTENT_DO_ACCOUNTING))
1378 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
1380 if (*bits & EXTENT_DO_ACCOUNTING)
1381 btrfs_delalloc_release_metadata(inode, len);
1383 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1385 btrfs_free_reserved_data_space(inode, len);
1387 spin_lock(&root->fs_info->delalloc_lock);
1388 root->fs_info->delalloc_bytes -= len;
1389 BTRFS_I(inode)->delalloc_bytes -= len;
1391 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1392 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1393 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1395 spin_unlock(&root->fs_info->delalloc_lock);
1401 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1402 * we don't create bios that span stripes or chunks
1404 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1405 size_t size, struct bio *bio,
1406 unsigned long bio_flags)
1408 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1409 struct btrfs_mapping_tree *map_tree;
1410 u64 logical = (u64)bio->bi_sector << 9;
1415 if (bio_flags & EXTENT_BIO_COMPRESSED)
1418 length = bio->bi_size;
1419 map_tree = &root->fs_info->mapping_tree;
1420 map_length = length;
1421 ret = btrfs_map_block(map_tree, READ, logical,
1422 &map_length, NULL, 0);
1424 if (map_length < length + size)
1430 * in order to insert checksums into the metadata in large chunks,
1431 * we wait until bio submission time. All the pages in the bio are
1432 * checksummed and sums are attached onto the ordered extent record.
1434 * At IO completion time the cums attached on the ordered extent record
1435 * are inserted into the btree
1437 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1438 struct bio *bio, int mirror_num,
1439 unsigned long bio_flags,
1442 struct btrfs_root *root = BTRFS_I(inode)->root;
1445 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1451 * in order to insert checksums into the metadata in large chunks,
1452 * we wait until bio submission time. All the pages in the bio are
1453 * checksummed and sums are attached onto the ordered extent record.
1455 * At IO completion time the cums attached on the ordered extent record
1456 * are inserted into the btree
1458 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1459 int mirror_num, unsigned long bio_flags,
1462 struct btrfs_root *root = BTRFS_I(inode)->root;
1463 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1467 * extent_io.c submission hook. This does the right thing for csum calculation
1468 * on write, or reading the csums from the tree before a read
1470 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1471 int mirror_num, unsigned long bio_flags,
1474 struct btrfs_root *root = BTRFS_I(inode)->root;
1478 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1480 if (is_free_space_inode(root, inode))
1481 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
1483 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1486 if (!(rw & REQ_WRITE)) {
1487 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1488 return btrfs_submit_compressed_read(inode, bio,
1489 mirror_num, bio_flags);
1490 } else if (!skip_sum) {
1491 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1496 } else if (!skip_sum) {
1497 /* csum items have already been cloned */
1498 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1500 /* we're doing a write, do the async checksumming */
1501 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1502 inode, rw, bio, mirror_num,
1503 bio_flags, bio_offset,
1504 __btrfs_submit_bio_start,
1505 __btrfs_submit_bio_done);
1509 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1513 * given a list of ordered sums record them in the inode. This happens
1514 * at IO completion time based on sums calculated at bio submission time.
1516 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1517 struct inode *inode, u64 file_offset,
1518 struct list_head *list)
1520 struct btrfs_ordered_sum *sum;
1522 list_for_each_entry(sum, list, list) {
1523 btrfs_csum_file_blocks(trans,
1524 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1529 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1530 struct extent_state **cached_state)
1532 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1534 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1535 cached_state, GFP_NOFS);
1538 /* see btrfs_writepage_start_hook for details on why this is required */
1539 struct btrfs_writepage_fixup {
1541 struct btrfs_work work;
1544 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1546 struct btrfs_writepage_fixup *fixup;
1547 struct btrfs_ordered_extent *ordered;
1548 struct extent_state *cached_state = NULL;
1550 struct inode *inode;
1554 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1558 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1559 ClearPageChecked(page);
1563 inode = page->mapping->host;
1564 page_start = page_offset(page);
1565 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1567 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1568 &cached_state, GFP_NOFS);
1570 /* already ordered? We're done */
1571 if (PagePrivate2(page))
1574 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1576 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1577 page_end, &cached_state, GFP_NOFS);
1579 btrfs_start_ordered_extent(inode, ordered, 1);
1584 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1585 ClearPageChecked(page);
1587 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1588 &cached_state, GFP_NOFS);
1591 page_cache_release(page);
1596 * There are a few paths in the higher layers of the kernel that directly
1597 * set the page dirty bit without asking the filesystem if it is a
1598 * good idea. This causes problems because we want to make sure COW
1599 * properly happens and the data=ordered rules are followed.
1601 * In our case any range that doesn't have the ORDERED bit set
1602 * hasn't been properly setup for IO. We kick off an async process
1603 * to fix it up. The async helper will wait for ordered extents, set
1604 * the delalloc bit and make it safe to write the page.
1606 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1608 struct inode *inode = page->mapping->host;
1609 struct btrfs_writepage_fixup *fixup;
1610 struct btrfs_root *root = BTRFS_I(inode)->root;
1612 /* this page is properly in the ordered list */
1613 if (TestClearPagePrivate2(page))
1616 if (PageChecked(page))
1619 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1623 SetPageChecked(page);
1624 page_cache_get(page);
1625 fixup->work.func = btrfs_writepage_fixup_worker;
1627 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1631 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1632 struct inode *inode, u64 file_pos,
1633 u64 disk_bytenr, u64 disk_num_bytes,
1634 u64 num_bytes, u64 ram_bytes,
1635 u8 compression, u8 encryption,
1636 u16 other_encoding, int extent_type)
1638 struct btrfs_root *root = BTRFS_I(inode)->root;
1639 struct btrfs_file_extent_item *fi;
1640 struct btrfs_path *path;
1641 struct extent_buffer *leaf;
1642 struct btrfs_key ins;
1646 path = btrfs_alloc_path();
1649 path->leave_spinning = 1;
1652 * we may be replacing one extent in the tree with another.
1653 * The new extent is pinned in the extent map, and we don't want
1654 * to drop it from the cache until it is completely in the btree.
1656 * So, tell btrfs_drop_extents to leave this extent in the cache.
1657 * the caller is expected to unpin it and allow it to be merged
1660 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1664 ins.objectid = btrfs_ino(inode);
1665 ins.offset = file_pos;
1666 ins.type = BTRFS_EXTENT_DATA_KEY;
1667 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1669 leaf = path->nodes[0];
1670 fi = btrfs_item_ptr(leaf, path->slots[0],
1671 struct btrfs_file_extent_item);
1672 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1673 btrfs_set_file_extent_type(leaf, fi, extent_type);
1674 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1675 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1676 btrfs_set_file_extent_offset(leaf, fi, 0);
1677 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1678 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1679 btrfs_set_file_extent_compression(leaf, fi, compression);
1680 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1681 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1683 btrfs_unlock_up_safe(path, 1);
1684 btrfs_set_lock_blocking(leaf);
1686 btrfs_mark_buffer_dirty(leaf);
1688 inode_add_bytes(inode, num_bytes);
1690 ins.objectid = disk_bytenr;
1691 ins.offset = disk_num_bytes;
1692 ins.type = BTRFS_EXTENT_ITEM_KEY;
1693 ret = btrfs_alloc_reserved_file_extent(trans, root,
1694 root->root_key.objectid,
1695 btrfs_ino(inode), file_pos, &ins);
1697 btrfs_free_path(path);
1703 * helper function for btrfs_finish_ordered_io, this
1704 * just reads in some of the csum leaves to prime them into ram
1705 * before we start the transaction. It limits the amount of btree
1706 * reads required while inside the transaction.
1708 /* as ordered data IO finishes, this gets called so we can finish
1709 * an ordered extent if the range of bytes in the file it covers are
1712 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1714 struct btrfs_root *root = BTRFS_I(inode)->root;
1715 struct btrfs_trans_handle *trans = NULL;
1716 struct btrfs_ordered_extent *ordered_extent = NULL;
1717 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1718 struct extent_state *cached_state = NULL;
1719 int compress_type = 0;
1723 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1727 BUG_ON(!ordered_extent);
1729 nolock = is_free_space_inode(root, inode);
1731 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1732 BUG_ON(!list_empty(&ordered_extent->list));
1733 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1736 trans = btrfs_join_transaction_nolock(root);
1738 trans = btrfs_join_transaction(root);
1739 BUG_ON(IS_ERR(trans));
1740 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1741 ret = btrfs_update_inode(trans, root, inode);
1747 lock_extent_bits(io_tree, ordered_extent->file_offset,
1748 ordered_extent->file_offset + ordered_extent->len - 1,
1749 0, &cached_state, GFP_NOFS);
1752 trans = btrfs_join_transaction_nolock(root);
1754 trans = btrfs_join_transaction(root);
1755 BUG_ON(IS_ERR(trans));
1756 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1758 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1759 compress_type = ordered_extent->compress_type;
1760 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1761 BUG_ON(compress_type);
1762 ret = btrfs_mark_extent_written(trans, inode,
1763 ordered_extent->file_offset,
1764 ordered_extent->file_offset +
1765 ordered_extent->len);
1768 BUG_ON(root == root->fs_info->tree_root);
1769 ret = insert_reserved_file_extent(trans, inode,
1770 ordered_extent->file_offset,
1771 ordered_extent->start,
1772 ordered_extent->disk_len,
1773 ordered_extent->len,
1774 ordered_extent->len,
1775 compress_type, 0, 0,
1776 BTRFS_FILE_EXTENT_REG);
1777 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1778 ordered_extent->file_offset,
1779 ordered_extent->len);
1782 unlock_extent_cached(io_tree, ordered_extent->file_offset,
1783 ordered_extent->file_offset +
1784 ordered_extent->len - 1, &cached_state, GFP_NOFS);
1786 add_pending_csums(trans, inode, ordered_extent->file_offset,
1787 &ordered_extent->list);
1789 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1791 ret = btrfs_update_inode(trans, root, inode);
1798 btrfs_end_transaction_nolock(trans, root);
1800 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
1802 btrfs_end_transaction(trans, root);
1806 btrfs_put_ordered_extent(ordered_extent);
1807 /* once for the tree */
1808 btrfs_put_ordered_extent(ordered_extent);
1813 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1814 struct extent_state *state, int uptodate)
1816 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
1818 ClearPagePrivate2(page);
1819 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1823 * When IO fails, either with EIO or csum verification fails, we
1824 * try other mirrors that might have a good copy of the data. This
1825 * io_failure_record is used to record state as we go through all the
1826 * mirrors. If another mirror has good data, the page is set up to date
1827 * and things continue. If a good mirror can't be found, the original
1828 * bio end_io callback is called to indicate things have failed.
1830 struct io_failure_record {
1835 unsigned long bio_flags;
1839 static int btrfs_io_failed_hook(struct bio *failed_bio,
1840 struct page *page, u64 start, u64 end,
1841 struct extent_state *state)
1843 struct io_failure_record *failrec = NULL;
1845 struct extent_map *em;
1846 struct inode *inode = page->mapping->host;
1847 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1848 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1855 ret = get_state_private(failure_tree, start, &private);
1857 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
1860 failrec->start = start;
1861 failrec->len = end - start + 1;
1862 failrec->last_mirror = 0;
1863 failrec->bio_flags = 0;
1865 read_lock(&em_tree->lock);
1866 em = lookup_extent_mapping(em_tree, start, failrec->len);
1867 if (em->start > start || em->start + em->len < start) {
1868 free_extent_map(em);
1871 read_unlock(&em_tree->lock);
1873 if (IS_ERR_OR_NULL(em)) {
1877 logical = start - em->start;
1878 logical = em->block_start + logical;
1879 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
1880 logical = em->block_start;
1881 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
1882 extent_set_compress_type(&failrec->bio_flags,
1885 failrec->logical = logical;
1886 free_extent_map(em);
1887 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
1888 EXTENT_DIRTY, GFP_NOFS);
1889 set_state_private(failure_tree, start,
1890 (u64)(unsigned long)failrec);
1892 failrec = (struct io_failure_record *)(unsigned long)private;
1894 num_copies = btrfs_num_copies(
1895 &BTRFS_I(inode)->root->fs_info->mapping_tree,
1896 failrec->logical, failrec->len);
1897 failrec->last_mirror++;
1899 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1900 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1903 if (state && state->start != failrec->start)
1905 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1907 if (!state || failrec->last_mirror > num_copies) {
1908 set_state_private(failure_tree, failrec->start, 0);
1909 clear_extent_bits(failure_tree, failrec->start,
1910 failrec->start + failrec->len - 1,
1911 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1915 bio = bio_alloc(GFP_NOFS, 1);
1916 bio->bi_private = state;
1917 bio->bi_end_io = failed_bio->bi_end_io;
1918 bio->bi_sector = failrec->logical >> 9;
1919 bio->bi_bdev = failed_bio->bi_bdev;
1922 bio_add_page(bio, page, failrec->len, start - page_offset(page));
1923 if (failed_bio->bi_rw & REQ_WRITE)
1928 ret = BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
1929 failrec->last_mirror,
1930 failrec->bio_flags, 0);
1935 * each time an IO finishes, we do a fast check in the IO failure tree
1936 * to see if we need to process or clean up an io_failure_record
1938 static int btrfs_clean_io_failures(struct inode *inode, u64 start)
1941 u64 private_failure;
1942 struct io_failure_record *failure;
1946 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1947 (u64)-1, 1, EXTENT_DIRTY, 0)) {
1948 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
1949 start, &private_failure);
1951 failure = (struct io_failure_record *)(unsigned long)
1953 set_state_private(&BTRFS_I(inode)->io_failure_tree,
1955 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
1957 failure->start + failure->len - 1,
1958 EXTENT_DIRTY | EXTENT_LOCKED,
1967 * when reads are done, we need to check csums to verify the data is correct
1968 * if there's a match, we allow the bio to finish. If not, we go through
1969 * the io_failure_record routines to find good copies
1971 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1972 struct extent_state *state)
1974 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1975 struct inode *inode = page->mapping->host;
1976 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1978 u64 private = ~(u32)0;
1980 struct btrfs_root *root = BTRFS_I(inode)->root;
1983 if (PageChecked(page)) {
1984 ClearPageChecked(page);
1988 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1991 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1992 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1993 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1998 if (state && state->start == start) {
1999 private = state->private;
2002 ret = get_state_private(io_tree, start, &private);
2004 kaddr = kmap_atomic(page, KM_USER0);
2008 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
2009 btrfs_csum_final(csum, (char *)&csum);
2010 if (csum != private)
2013 kunmap_atomic(kaddr, KM_USER0);
2015 /* if the io failure tree for this inode is non-empty,
2016 * check to see if we've recovered from a failed IO
2018 btrfs_clean_io_failures(inode, start);
2022 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
2024 (unsigned long long)btrfs_ino(page->mapping->host),
2025 (unsigned long long)start, csum,
2026 (unsigned long long)private);
2027 memset(kaddr + offset, 1, end - start + 1);
2028 flush_dcache_page(page);
2029 kunmap_atomic(kaddr, KM_USER0);
2035 struct delayed_iput {
2036 struct list_head list;
2037 struct inode *inode;
2040 void btrfs_add_delayed_iput(struct inode *inode)
2042 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2043 struct delayed_iput *delayed;
2045 if (atomic_add_unless(&inode->i_count, -1, 1))
2048 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2049 delayed->inode = inode;
2051 spin_lock(&fs_info->delayed_iput_lock);
2052 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2053 spin_unlock(&fs_info->delayed_iput_lock);
2056 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2059 struct btrfs_fs_info *fs_info = root->fs_info;
2060 struct delayed_iput *delayed;
2063 spin_lock(&fs_info->delayed_iput_lock);
2064 empty = list_empty(&fs_info->delayed_iputs);
2065 spin_unlock(&fs_info->delayed_iput_lock);
2069 down_read(&root->fs_info->cleanup_work_sem);
2070 spin_lock(&fs_info->delayed_iput_lock);
2071 list_splice_init(&fs_info->delayed_iputs, &list);
2072 spin_unlock(&fs_info->delayed_iput_lock);
2074 while (!list_empty(&list)) {
2075 delayed = list_entry(list.next, struct delayed_iput, list);
2076 list_del(&delayed->list);
2077 iput(delayed->inode);
2080 up_read(&root->fs_info->cleanup_work_sem);
2084 * calculate extra metadata reservation when snapshotting a subvolume
2085 * contains orphan files.
2087 void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans,
2088 struct btrfs_pending_snapshot *pending,
2089 u64 *bytes_to_reserve)
2091 struct btrfs_root *root;
2092 struct btrfs_block_rsv *block_rsv;
2096 root = pending->root;
2097 if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
2100 block_rsv = root->orphan_block_rsv;
2102 /* orphan block reservation for the snapshot */
2103 num_bytes = block_rsv->size;
2106 * after the snapshot is created, COWing tree blocks may use more
2107 * space than it frees. So we should make sure there is enough
2110 index = trans->transid & 0x1;
2111 if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
2112 num_bytes += block_rsv->size -
2113 (block_rsv->reserved + block_rsv->freed[index]);
2116 *bytes_to_reserve += num_bytes;
2119 void btrfs_orphan_post_snapshot(struct btrfs_trans_handle *trans,
2120 struct btrfs_pending_snapshot *pending)
2122 struct btrfs_root *root = pending->root;
2123 struct btrfs_root *snap = pending->snap;
2124 struct btrfs_block_rsv *block_rsv;
2129 if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
2132 /* refill source subvolume's orphan block reservation */
2133 block_rsv = root->orphan_block_rsv;
2134 index = trans->transid & 0x1;
2135 if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
2136 num_bytes = block_rsv->size -
2137 (block_rsv->reserved + block_rsv->freed[index]);
2138 ret = btrfs_block_rsv_migrate(&pending->block_rsv,
2139 root->orphan_block_rsv,
2144 /* setup orphan block reservation for the snapshot */
2145 block_rsv = btrfs_alloc_block_rsv(snap);
2148 btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
2149 snap->orphan_block_rsv = block_rsv;
2151 num_bytes = root->orphan_block_rsv->size;
2152 ret = btrfs_block_rsv_migrate(&pending->block_rsv,
2153 block_rsv, num_bytes);
2157 /* insert orphan item for the snapshot */
2158 WARN_ON(!root->orphan_item_inserted);
2159 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2160 snap->root_key.objectid);
2162 snap->orphan_item_inserted = 1;
2166 enum btrfs_orphan_cleanup_state {
2167 ORPHAN_CLEANUP_STARTED = 1,
2168 ORPHAN_CLEANUP_DONE = 2,
2172 * This is called in transaction commmit time. If there are no orphan
2173 * files in the subvolume, it removes orphan item and frees block_rsv
2176 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2177 struct btrfs_root *root)
2181 if (!list_empty(&root->orphan_list) ||
2182 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2185 if (root->orphan_item_inserted &&
2186 btrfs_root_refs(&root->root_item) > 0) {
2187 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2188 root->root_key.objectid);
2190 root->orphan_item_inserted = 0;
2193 if (root->orphan_block_rsv) {
2194 WARN_ON(root->orphan_block_rsv->size > 0);
2195 btrfs_free_block_rsv(root, root->orphan_block_rsv);
2196 root->orphan_block_rsv = NULL;
2201 * This creates an orphan entry for the given inode in case something goes
2202 * wrong in the middle of an unlink/truncate.
2204 * NOTE: caller of this function should reserve 5 units of metadata for
2207 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2209 struct btrfs_root *root = BTRFS_I(inode)->root;
2210 struct btrfs_block_rsv *block_rsv = NULL;
2215 if (!root->orphan_block_rsv) {
2216 block_rsv = btrfs_alloc_block_rsv(root);
2220 spin_lock(&root->orphan_lock);
2221 if (!root->orphan_block_rsv) {
2222 root->orphan_block_rsv = block_rsv;
2223 } else if (block_rsv) {
2224 btrfs_free_block_rsv(root, block_rsv);
2228 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2229 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2232 * For proper ENOSPC handling, we should do orphan
2233 * cleanup when mounting. But this introduces backward
2234 * compatibility issue.
2236 if (!xchg(&root->orphan_item_inserted, 1))
2244 if (!BTRFS_I(inode)->orphan_meta_reserved) {
2245 BTRFS_I(inode)->orphan_meta_reserved = 1;
2248 spin_unlock(&root->orphan_lock);
2251 btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
2253 /* grab metadata reservation from transaction handle */
2255 ret = btrfs_orphan_reserve_metadata(trans, inode);
2259 /* insert an orphan item to track this unlinked/truncated file */
2261 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2265 /* insert an orphan item to track subvolume contains orphan files */
2267 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2268 root->root_key.objectid);
2275 * We have done the truncate/delete so we can go ahead and remove the orphan
2276 * item for this particular inode.
2278 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2280 struct btrfs_root *root = BTRFS_I(inode)->root;
2281 int delete_item = 0;
2282 int release_rsv = 0;
2285 spin_lock(&root->orphan_lock);
2286 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2287 list_del_init(&BTRFS_I(inode)->i_orphan);
2291 if (BTRFS_I(inode)->orphan_meta_reserved) {
2292 BTRFS_I(inode)->orphan_meta_reserved = 0;
2295 spin_unlock(&root->orphan_lock);
2297 if (trans && delete_item) {
2298 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
2303 btrfs_orphan_release_metadata(inode);
2309 * this cleans up any orphans that may be left on the list from the last use
2312 int btrfs_orphan_cleanup(struct btrfs_root *root)
2314 struct btrfs_path *path;
2315 struct extent_buffer *leaf;
2316 struct btrfs_key key, found_key;
2317 struct btrfs_trans_handle *trans;
2318 struct inode *inode;
2319 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2321 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
2324 path = btrfs_alloc_path();
2331 key.objectid = BTRFS_ORPHAN_OBJECTID;
2332 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2333 key.offset = (u64)-1;
2336 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2341 * if ret == 0 means we found what we were searching for, which
2342 * is weird, but possible, so only screw with path if we didn't
2343 * find the key and see if we have stuff that matches
2347 if (path->slots[0] == 0)
2352 /* pull out the item */
2353 leaf = path->nodes[0];
2354 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2356 /* make sure the item matches what we want */
2357 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2359 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2362 /* release the path since we're done with it */
2363 btrfs_release_path(path);
2366 * this is where we are basically btrfs_lookup, without the
2367 * crossing root thing. we store the inode number in the
2368 * offset of the orphan item.
2370 found_key.objectid = found_key.offset;
2371 found_key.type = BTRFS_INODE_ITEM_KEY;
2372 found_key.offset = 0;
2373 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2374 if (IS_ERR(inode)) {
2375 ret = PTR_ERR(inode);
2380 * add this inode to the orphan list so btrfs_orphan_del does
2381 * the proper thing when we hit it
2383 spin_lock(&root->orphan_lock);
2384 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2385 spin_unlock(&root->orphan_lock);
2388 * if this is a bad inode, means we actually succeeded in
2389 * removing the inode, but not the orphan record, which means
2390 * we need to manually delete the orphan since iput will just
2391 * do a destroy_inode
2393 if (is_bad_inode(inode)) {
2394 trans = btrfs_start_transaction(root, 0);
2395 if (IS_ERR(trans)) {
2396 ret = PTR_ERR(trans);
2399 btrfs_orphan_del(trans, inode);
2400 btrfs_end_transaction(trans, root);
2405 /* if we have links, this was a truncate, lets do that */
2406 if (inode->i_nlink) {
2407 if (!S_ISREG(inode->i_mode)) {
2413 ret = btrfs_truncate(inode);
2418 /* this will do delete_inode and everything for us */
2423 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
2425 if (root->orphan_block_rsv)
2426 btrfs_block_rsv_release(root, root->orphan_block_rsv,
2429 if (root->orphan_block_rsv || root->orphan_item_inserted) {
2430 trans = btrfs_join_transaction(root);
2432 btrfs_end_transaction(trans, root);
2436 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2438 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2442 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
2443 btrfs_free_path(path);
2448 * very simple check to peek ahead in the leaf looking for xattrs. If we
2449 * don't find any xattrs, we know there can't be any acls.
2451 * slot is the slot the inode is in, objectid is the objectid of the inode
2453 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2454 int slot, u64 objectid)
2456 u32 nritems = btrfs_header_nritems(leaf);
2457 struct btrfs_key found_key;
2461 while (slot < nritems) {
2462 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2464 /* we found a different objectid, there must not be acls */
2465 if (found_key.objectid != objectid)
2468 /* we found an xattr, assume we've got an acl */
2469 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2473 * we found a key greater than an xattr key, there can't
2474 * be any acls later on
2476 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2483 * it goes inode, inode backrefs, xattrs, extents,
2484 * so if there are a ton of hard links to an inode there can
2485 * be a lot of backrefs. Don't waste time searching too hard,
2486 * this is just an optimization
2491 /* we hit the end of the leaf before we found an xattr or
2492 * something larger than an xattr. We have to assume the inode
2499 * read an inode from the btree into the in-memory inode
2501 static void btrfs_read_locked_inode(struct inode *inode)
2503 struct btrfs_path *path;
2504 struct extent_buffer *leaf;
2505 struct btrfs_inode_item *inode_item;
2506 struct btrfs_timespec *tspec;
2507 struct btrfs_root *root = BTRFS_I(inode)->root;
2508 struct btrfs_key location;
2512 bool filled = false;
2514 ret = btrfs_fill_inode(inode, &rdev);
2518 path = btrfs_alloc_path();
2520 path->leave_spinning = 1;
2521 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2523 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2527 leaf = path->nodes[0];
2532 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2533 struct btrfs_inode_item);
2534 if (!leaf->map_token)
2535 map_private_extent_buffer(leaf, (unsigned long)inode_item,
2536 sizeof(struct btrfs_inode_item),
2537 &leaf->map_token, &leaf->kaddr,
2538 &leaf->map_start, &leaf->map_len,
2541 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2542 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
2543 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2544 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2545 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2547 tspec = btrfs_inode_atime(inode_item);
2548 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2549 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2551 tspec = btrfs_inode_mtime(inode_item);
2552 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2553 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2555 tspec = btrfs_inode_ctime(inode_item);
2556 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2557 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2559 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2560 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2561 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2562 inode->i_generation = BTRFS_I(inode)->generation;
2564 rdev = btrfs_inode_rdev(leaf, inode_item);
2566 BTRFS_I(inode)->index_cnt = (u64)-1;
2567 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2570 * try to precache a NULL acl entry for files that don't have
2571 * any xattrs or acls
2573 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
2576 cache_no_acl(inode);
2578 if (leaf->map_token) {
2579 unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
2580 leaf->map_token = NULL;
2583 btrfs_free_path(path);
2585 switch (inode->i_mode & S_IFMT) {
2587 inode->i_mapping->a_ops = &btrfs_aops;
2588 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2589 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2590 inode->i_fop = &btrfs_file_operations;
2591 inode->i_op = &btrfs_file_inode_operations;
2594 inode->i_fop = &btrfs_dir_file_operations;
2595 if (root == root->fs_info->tree_root)
2596 inode->i_op = &btrfs_dir_ro_inode_operations;
2598 inode->i_op = &btrfs_dir_inode_operations;
2601 inode->i_op = &btrfs_symlink_inode_operations;
2602 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2603 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2606 inode->i_op = &btrfs_special_inode_operations;
2607 init_special_inode(inode, inode->i_mode, rdev);
2611 btrfs_update_iflags(inode);
2615 btrfs_free_path(path);
2616 make_bad_inode(inode);
2620 * given a leaf and an inode, copy the inode fields into the leaf
2622 static void fill_inode_item(struct btrfs_trans_handle *trans,
2623 struct extent_buffer *leaf,
2624 struct btrfs_inode_item *item,
2625 struct inode *inode)
2627 if (!leaf->map_token)
2628 map_private_extent_buffer(leaf, (unsigned long)item,
2629 sizeof(struct btrfs_inode_item),
2630 &leaf->map_token, &leaf->kaddr,
2631 &leaf->map_start, &leaf->map_len,
2634 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2635 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2636 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2637 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2638 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2640 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2641 inode->i_atime.tv_sec);
2642 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2643 inode->i_atime.tv_nsec);
2645 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2646 inode->i_mtime.tv_sec);
2647 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2648 inode->i_mtime.tv_nsec);
2650 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2651 inode->i_ctime.tv_sec);
2652 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2653 inode->i_ctime.tv_nsec);
2655 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2656 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2657 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2658 btrfs_set_inode_transid(leaf, item, trans->transid);
2659 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2660 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2661 btrfs_set_inode_block_group(leaf, item, 0);
2663 if (leaf->map_token) {
2664 unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
2665 leaf->map_token = NULL;
2670 * copy everything in the in-memory inode into the btree.
2672 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2673 struct btrfs_root *root, struct inode *inode)
2675 struct btrfs_inode_item *inode_item;
2676 struct btrfs_path *path;
2677 struct extent_buffer *leaf;
2681 * If root is tree root, it means this inode is used to
2682 * store free space information. And these inodes are updated
2683 * when committing the transaction, so they needn't delaye to
2684 * be updated, or deadlock will occured.
2686 if (!is_free_space_inode(root, inode)) {
2687 ret = btrfs_delayed_update_inode(trans, root, inode);
2689 btrfs_set_inode_last_trans(trans, inode);
2693 path = btrfs_alloc_path();
2697 path->leave_spinning = 1;
2698 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
2706 btrfs_unlock_up_safe(path, 1);
2707 leaf = path->nodes[0];
2708 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2709 struct btrfs_inode_item);
2711 fill_inode_item(trans, leaf, inode_item, inode);
2712 btrfs_mark_buffer_dirty(leaf);
2713 btrfs_set_inode_last_trans(trans, inode);
2716 btrfs_free_path(path);
2721 * unlink helper that gets used here in inode.c and in the tree logging
2722 * recovery code. It remove a link in a directory with a given name, and
2723 * also drops the back refs in the inode to the directory
2725 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2726 struct btrfs_root *root,
2727 struct inode *dir, struct inode *inode,
2728 const char *name, int name_len)
2730 struct btrfs_path *path;
2732 struct extent_buffer *leaf;
2733 struct btrfs_dir_item *di;
2734 struct btrfs_key key;
2736 u64 ino = btrfs_ino(inode);
2737 u64 dir_ino = btrfs_ino(dir);
2739 path = btrfs_alloc_path();
2745 path->leave_spinning = 1;
2746 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2747 name, name_len, -1);
2756 leaf = path->nodes[0];
2757 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2758 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2761 btrfs_release_path(path);
2763 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
2766 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2767 "inode %llu parent %llu\n", name_len, name,
2768 (unsigned long long)ino, (unsigned long long)dir_ino);
2772 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2776 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2778 BUG_ON(ret != 0 && ret != -ENOENT);
2780 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2785 btrfs_free_path(path);
2789 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2790 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2791 btrfs_update_inode(trans, root, dir);
2796 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2797 struct btrfs_root *root,
2798 struct inode *dir, struct inode *inode,
2799 const char *name, int name_len)
2802 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
2804 btrfs_drop_nlink(inode);
2805 ret = btrfs_update_inode(trans, root, inode);
2811 /* helper to check if there is any shared block in the path */
2812 static int check_path_shared(struct btrfs_root *root,
2813 struct btrfs_path *path)
2815 struct extent_buffer *eb;
2819 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2822 if (!path->nodes[level])
2824 eb = path->nodes[level];
2825 if (!btrfs_block_can_be_shared(root, eb))
2827 ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len,
2836 * helper to start transaction for unlink and rmdir.
2838 * unlink and rmdir are special in btrfs, they do not always free space.
2839 * so in enospc case, we should make sure they will free space before
2840 * allowing them to use the global metadata reservation.
2842 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
2843 struct dentry *dentry)
2845 struct btrfs_trans_handle *trans;
2846 struct btrfs_root *root = BTRFS_I(dir)->root;
2847 struct btrfs_path *path;
2848 struct btrfs_inode_ref *ref;
2849 struct btrfs_dir_item *di;
2850 struct inode *inode = dentry->d_inode;
2855 u64 ino = btrfs_ino(inode);
2856 u64 dir_ino = btrfs_ino(dir);
2858 trans = btrfs_start_transaction(root, 10);
2859 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
2862 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
2863 return ERR_PTR(-ENOSPC);
2865 /* check if there is someone else holds reference */
2866 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
2867 return ERR_PTR(-ENOSPC);
2869 if (atomic_read(&inode->i_count) > 2)
2870 return ERR_PTR(-ENOSPC);
2872 if (xchg(&root->fs_info->enospc_unlink, 1))
2873 return ERR_PTR(-ENOSPC);
2875 path = btrfs_alloc_path();
2877 root->fs_info->enospc_unlink = 0;
2878 return ERR_PTR(-ENOMEM);
2881 trans = btrfs_start_transaction(root, 0);
2882 if (IS_ERR(trans)) {
2883 btrfs_free_path(path);
2884 root->fs_info->enospc_unlink = 0;
2888 path->skip_locking = 1;
2889 path->search_commit_root = 1;
2891 ret = btrfs_lookup_inode(trans, root, path,
2892 &BTRFS_I(dir)->location, 0);
2898 if (check_path_shared(root, path))
2903 btrfs_release_path(path);
2905 ret = btrfs_lookup_inode(trans, root, path,
2906 &BTRFS_I(inode)->location, 0);
2912 if (check_path_shared(root, path))
2917 btrfs_release_path(path);
2919 if (ret == 0 && S_ISREG(inode->i_mode)) {
2920 ret = btrfs_lookup_file_extent(trans, root, path,
2927 if (check_path_shared(root, path))
2929 btrfs_release_path(path);
2937 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2938 dentry->d_name.name, dentry->d_name.len, 0);
2944 if (check_path_shared(root, path))
2950 btrfs_release_path(path);
2952 ref = btrfs_lookup_inode_ref(trans, root, path,
2953 dentry->d_name.name, dentry->d_name.len,
2960 if (check_path_shared(root, path))
2962 index = btrfs_inode_ref_index(path->nodes[0], ref);
2963 btrfs_release_path(path);
2966 * This is a commit root search, if we can lookup inode item and other
2967 * relative items in the commit root, it means the transaction of
2968 * dir/file creation has been committed, and the dir index item that we
2969 * delay to insert has also been inserted into the commit root. So
2970 * we needn't worry about the delayed insertion of the dir index item
2973 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
2974 dentry->d_name.name, dentry->d_name.len, 0);
2979 BUG_ON(ret == -ENOENT);
2980 if (check_path_shared(root, path))
2985 btrfs_free_path(path);
2987 btrfs_end_transaction(trans, root);
2988 root->fs_info->enospc_unlink = 0;
2989 return ERR_PTR(err);
2992 trans->block_rsv = &root->fs_info->global_block_rsv;
2996 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
2997 struct btrfs_root *root)
2999 if (trans->block_rsv == &root->fs_info->global_block_rsv) {
3000 BUG_ON(!root->fs_info->enospc_unlink);
3001 root->fs_info->enospc_unlink = 0;
3003 btrfs_end_transaction_throttle(trans, root);
3006 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3008 struct btrfs_root *root = BTRFS_I(dir)->root;
3009 struct btrfs_trans_handle *trans;
3010 struct inode *inode = dentry->d_inode;
3012 unsigned long nr = 0;
3014 trans = __unlink_start_trans(dir, dentry);
3016 return PTR_ERR(trans);
3018 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
3020 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3021 dentry->d_name.name, dentry->d_name.len);
3024 if (inode->i_nlink == 0) {
3025 ret = btrfs_orphan_add(trans, inode);
3029 nr = trans->blocks_used;
3030 __unlink_end_trans(trans, root);
3031 btrfs_btree_balance_dirty(root, nr);
3035 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3036 struct btrfs_root *root,
3037 struct inode *dir, u64 objectid,
3038 const char *name, int name_len)
3040 struct btrfs_path *path;
3041 struct extent_buffer *leaf;
3042 struct btrfs_dir_item *di;
3043 struct btrfs_key key;
3046 u64 dir_ino = btrfs_ino(dir);
3048 path = btrfs_alloc_path();
3052 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3053 name, name_len, -1);
3054 BUG_ON(IS_ERR_OR_NULL(di));
3056 leaf = path->nodes[0];
3057 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3058 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3059 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3061 btrfs_release_path(path);
3063 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
3064 objectid, root->root_key.objectid,
3065 dir_ino, &index, name, name_len);
3067 BUG_ON(ret != -ENOENT);
3068 di = btrfs_search_dir_index_item(root, path, dir_ino,
3070 BUG_ON(IS_ERR_OR_NULL(di));
3072 leaf = path->nodes[0];
3073 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3074 btrfs_release_path(path);
3077 btrfs_release_path(path);
3079 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
3082 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
3083 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
3084 ret = btrfs_update_inode(trans, root, dir);
3087 btrfs_free_path(path);
3091 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
3093 struct inode *inode = dentry->d_inode;
3095 struct btrfs_root *root = BTRFS_I(dir)->root;
3096 struct btrfs_trans_handle *trans;
3097 unsigned long nr = 0;
3099 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
3100 btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3103 trans = __unlink_start_trans(dir, dentry);
3105 return PTR_ERR(trans);
3107 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3108 err = btrfs_unlink_subvol(trans, root, dir,
3109 BTRFS_I(inode)->location.objectid,
3110 dentry->d_name.name,
3111 dentry->d_name.len);
3115 err = btrfs_orphan_add(trans, inode);
3119 /* now the directory is empty */
3120 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3121 dentry->d_name.name, dentry->d_name.len);
3123 btrfs_i_size_write(inode, 0);
3125 nr = trans->blocks_used;
3126 __unlink_end_trans(trans, root);
3127 btrfs_btree_balance_dirty(root, nr);
3133 * this can truncate away extent items, csum items and directory items.
3134 * It starts at a high offset and removes keys until it can't find
3135 * any higher than new_size
3137 * csum items that cross the new i_size are truncated to the new size
3140 * min_type is the minimum key type to truncate down to. If set to 0, this
3141 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3143 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3144 struct btrfs_root *root,
3145 struct inode *inode,
3146 u64 new_size, u32 min_type)
3148 struct btrfs_path *path;
3149 struct extent_buffer *leaf;
3150 struct btrfs_file_extent_item *fi;
3151 struct btrfs_key key;
3152 struct btrfs_key found_key;
3153 u64 extent_start = 0;
3154 u64 extent_num_bytes = 0;
3155 u64 extent_offset = 0;
3157 u64 mask = root->sectorsize - 1;
3158 u32 found_type = (u8)-1;
3161 int pending_del_nr = 0;
3162 int pending_del_slot = 0;
3163 int extent_type = -1;
3167 u64 ino = btrfs_ino(inode);
3169 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3171 if (root->ref_cows || root == root->fs_info->tree_root)
3172 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
3175 * This function is also used to drop the items in the log tree before
3176 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3177 * it is used to drop the loged items. So we shouldn't kill the delayed
3180 if (min_type == 0 && root == BTRFS_I(inode)->root)
3181 btrfs_kill_delayed_inode_items(inode);
3183 path = btrfs_alloc_path();
3188 key.offset = (u64)-1;
3192 path->leave_spinning = 1;
3193 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3200 /* there are no items in the tree for us to truncate, we're
3203 if (path->slots[0] == 0)
3210 leaf = path->nodes[0];
3211 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3212 found_type = btrfs_key_type(&found_key);
3215 if (found_key.objectid != ino)
3218 if (found_type < min_type)
3221 item_end = found_key.offset;
3222 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3223 fi = btrfs_item_ptr(leaf, path->slots[0],
3224 struct btrfs_file_extent_item);
3225 extent_type = btrfs_file_extent_type(leaf, fi);
3226 encoding = btrfs_file_extent_compression(leaf, fi);
3227 encoding |= btrfs_file_extent_encryption(leaf, fi);
3228 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
3230 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3232 btrfs_file_extent_num_bytes(leaf, fi);
3233 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3234 item_end += btrfs_file_extent_inline_len(leaf,
3239 if (found_type > min_type) {
3242 if (item_end < new_size)
3244 if (found_key.offset >= new_size)
3250 /* FIXME, shrink the extent if the ref count is only 1 */
3251 if (found_type != BTRFS_EXTENT_DATA_KEY)
3254 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3256 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3257 if (!del_item && !encoding) {
3258 u64 orig_num_bytes =
3259 btrfs_file_extent_num_bytes(leaf, fi);
3260 extent_num_bytes = new_size -
3261 found_key.offset + root->sectorsize - 1;
3262 extent_num_bytes = extent_num_bytes &
3263 ~((u64)root->sectorsize - 1);
3264 btrfs_set_file_extent_num_bytes(leaf, fi,
3266 num_dec = (orig_num_bytes -
3268 if (root->ref_cows && extent_start != 0)
3269 inode_sub_bytes(inode, num_dec);
3270 btrfs_mark_buffer_dirty(leaf);
3273 btrfs_file_extent_disk_num_bytes(leaf,
3275 extent_offset = found_key.offset -
3276 btrfs_file_extent_offset(leaf, fi);
3278 /* FIXME blocksize != 4096 */
3279 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
3280 if (extent_start != 0) {
3283 inode_sub_bytes(inode, num_dec);
3286 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3288 * we can't truncate inline items that have had
3292 btrfs_file_extent_compression(leaf, fi) == 0 &&
3293 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3294 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3295 u32 size = new_size - found_key.offset;
3297 if (root->ref_cows) {
3298 inode_sub_bytes(inode, item_end + 1 -
3302 btrfs_file_extent_calc_inline_size(size);
3303 ret = btrfs_truncate_item(trans, root, path,
3305 } else if (root->ref_cows) {
3306 inode_sub_bytes(inode, item_end + 1 -
3312 if (!pending_del_nr) {
3313 /* no pending yet, add ourselves */
3314 pending_del_slot = path->slots[0];
3316 } else if (pending_del_nr &&
3317 path->slots[0] + 1 == pending_del_slot) {
3318 /* hop on the pending chunk */
3320 pending_del_slot = path->slots[0];
3327 if (found_extent && (root->ref_cows ||
3328 root == root->fs_info->tree_root)) {
3329 btrfs_set_path_blocking(path);
3330 ret = btrfs_free_extent(trans, root, extent_start,
3331 extent_num_bytes, 0,
3332 btrfs_header_owner(leaf),
3333 ino, extent_offset);
3337 if (found_type == BTRFS_INODE_ITEM_KEY)
3340 if (path->slots[0] == 0 ||
3341 path->slots[0] != pending_del_slot) {
3342 if (root->ref_cows &&
3343 BTRFS_I(inode)->location.objectid !=
3344 BTRFS_FREE_INO_OBJECTID) {
3348 if (pending_del_nr) {
3349 ret = btrfs_del_items(trans, root, path,
3355 btrfs_release_path(path);
3362 if (pending_del_nr) {
3363 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3367 btrfs_free_path(path);
3372 * taken from block_truncate_page, but does cow as it zeros out
3373 * any bytes left in the last page in the file.
3375 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3377 struct inode *inode = mapping->host;
3378 struct btrfs_root *root = BTRFS_I(inode)->root;
3379 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3380 struct btrfs_ordered_extent *ordered;
3381 struct extent_state *cached_state = NULL;
3383 u32 blocksize = root->sectorsize;
3384 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3385 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3391 if ((offset & (blocksize - 1)) == 0)
3393 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
3399 page = grab_cache_page(mapping, index);
3401 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3405 page_start = page_offset(page);
3406 page_end = page_start + PAGE_CACHE_SIZE - 1;
3408 if (!PageUptodate(page)) {
3409 ret = btrfs_readpage(NULL, page);
3411 if (page->mapping != mapping) {
3413 page_cache_release(page);
3416 if (!PageUptodate(page)) {
3421 wait_on_page_writeback(page);
3423 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
3425 set_page_extent_mapped(page);
3427 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3429 unlock_extent_cached(io_tree, page_start, page_end,
3430 &cached_state, GFP_NOFS);
3432 page_cache_release(page);
3433 btrfs_start_ordered_extent(inode, ordered, 1);
3434 btrfs_put_ordered_extent(ordered);
3438 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
3439 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3440 0, 0, &cached_state, GFP_NOFS);
3442 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
3445 unlock_extent_cached(io_tree, page_start, page_end,
3446 &cached_state, GFP_NOFS);
3451 if (offset != PAGE_CACHE_SIZE) {
3453 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3454 flush_dcache_page(page);
3457 ClearPageChecked(page);
3458 set_page_dirty(page);
3459 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
3464 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3466 page_cache_release(page);
3472 * This function puts in dummy file extents for the area we're creating a hole
3473 * for. So if we are truncating this file to a larger size we need to insert
3474 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
3475 * the range between oldsize and size
3477 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
3479 struct btrfs_trans_handle *trans;
3480 struct btrfs_root *root = BTRFS_I(inode)->root;
3481 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3482 struct extent_map *em = NULL;
3483 struct extent_state *cached_state = NULL;
3484 u64 mask = root->sectorsize - 1;
3485 u64 hole_start = (oldsize + mask) & ~mask;
3486 u64 block_end = (size + mask) & ~mask;
3492 if (size <= hole_start)
3496 struct btrfs_ordered_extent *ordered;
3497 btrfs_wait_ordered_range(inode, hole_start,
3498 block_end - hole_start);
3499 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
3500 &cached_state, GFP_NOFS);
3501 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3504 unlock_extent_cached(io_tree, hole_start, block_end - 1,
3505 &cached_state, GFP_NOFS);
3506 btrfs_put_ordered_extent(ordered);
3509 cur_offset = hole_start;
3511 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3512 block_end - cur_offset, 0);
3513 BUG_ON(IS_ERR_OR_NULL(em));
3514 last_byte = min(extent_map_end(em), block_end);
3515 last_byte = (last_byte + mask) & ~mask;
3516 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3518 hole_size = last_byte - cur_offset;
3520 trans = btrfs_start_transaction(root, 2);
3521 if (IS_ERR(trans)) {
3522 err = PTR_ERR(trans);
3526 err = btrfs_drop_extents(trans, inode, cur_offset,
3527 cur_offset + hole_size,
3532 err = btrfs_insert_file_extent(trans, root,
3533 btrfs_ino(inode), cur_offset, 0,
3534 0, hole_size, 0, hole_size,
3539 btrfs_drop_extent_cache(inode, hole_start,
3542 btrfs_end_transaction(trans, root);
3544 free_extent_map(em);
3546 cur_offset = last_byte;
3547 if (cur_offset >= block_end)
3551 free_extent_map(em);
3552 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
3557 static int btrfs_setsize(struct inode *inode, loff_t newsize)
3559 loff_t oldsize = i_size_read(inode);
3562 if (newsize == oldsize)
3565 if (newsize > oldsize) {
3566 i_size_write(inode, newsize);
3567 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
3568 truncate_pagecache(inode, oldsize, newsize);
3569 ret = btrfs_cont_expand(inode, oldsize, newsize);
3571 btrfs_setsize(inode, oldsize);
3575 mark_inode_dirty(inode);
3579 * We're truncating a file that used to have good data down to
3580 * zero. Make sure it gets into the ordered flush list so that
3581 * any new writes get down to disk quickly.
3584 BTRFS_I(inode)->ordered_data_close = 1;
3586 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3587 truncate_setsize(inode, newsize);
3588 ret = btrfs_truncate(inode);
3594 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3596 struct inode *inode = dentry->d_inode;
3597 struct btrfs_root *root = BTRFS_I(inode)->root;
3600 if (btrfs_root_readonly(root))
3603 err = inode_change_ok(inode, attr);
3607 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3608 err = btrfs_setsize(inode, attr->ia_size);
3613 if (attr->ia_valid) {
3614 setattr_copy(inode, attr);
3615 mark_inode_dirty(inode);
3617 if (attr->ia_valid & ATTR_MODE)
3618 err = btrfs_acl_chmod(inode);
3624 void btrfs_evict_inode(struct inode *inode)
3626 struct btrfs_trans_handle *trans;
3627 struct btrfs_root *root = BTRFS_I(inode)->root;
3631 trace_btrfs_inode_evict(inode);
3633 truncate_inode_pages(&inode->i_data, 0);
3634 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
3635 is_free_space_inode(root, inode)))
3638 if (is_bad_inode(inode)) {
3639 btrfs_orphan_del(NULL, inode);
3642 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
3643 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3645 if (root->fs_info->log_root_recovering) {
3646 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3650 if (inode->i_nlink > 0) {
3651 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3655 btrfs_i_size_write(inode, 0);
3658 trans = btrfs_join_transaction(root);
3659 BUG_ON(IS_ERR(trans));
3660 trans->block_rsv = root->orphan_block_rsv;
3662 ret = btrfs_block_rsv_check(trans, root,
3663 root->orphan_block_rsv, 0, 5);
3665 BUG_ON(ret != -EAGAIN);
3666 ret = btrfs_commit_transaction(trans, root);
3671 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3675 nr = trans->blocks_used;
3676 btrfs_end_transaction(trans, root);
3678 btrfs_btree_balance_dirty(root, nr);
3683 ret = btrfs_orphan_del(trans, inode);
3687 if (!(root == root->fs_info->tree_root ||
3688 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
3689 btrfs_return_ino(root, btrfs_ino(inode));
3691 nr = trans->blocks_used;
3692 btrfs_end_transaction(trans, root);
3693 btrfs_btree_balance_dirty(root, nr);
3695 end_writeback(inode);
3700 * this returns the key found in the dir entry in the location pointer.
3701 * If no dir entries were found, location->objectid is 0.
3703 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3704 struct btrfs_key *location)
3706 const char *name = dentry->d_name.name;
3707 int namelen = dentry->d_name.len;
3708 struct btrfs_dir_item *di;
3709 struct btrfs_path *path;
3710 struct btrfs_root *root = BTRFS_I(dir)->root;
3713 path = btrfs_alloc_path();
3716 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
3721 if (IS_ERR_OR_NULL(di))
3724 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3726 btrfs_free_path(path);
3729 location->objectid = 0;
3734 * when we hit a tree root in a directory, the btrfs part of the inode
3735 * needs to be changed to reflect the root directory of the tree root. This
3736 * is kind of like crossing a mount point.
3738 static int fixup_tree_root_location(struct btrfs_root *root,
3740 struct dentry *dentry,
3741 struct btrfs_key *location,
3742 struct btrfs_root **sub_root)
3744 struct btrfs_path *path;
3745 struct btrfs_root *new_root;
3746 struct btrfs_root_ref *ref;
3747 struct extent_buffer *leaf;
3751 path = btrfs_alloc_path();
3758 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3759 BTRFS_I(dir)->root->root_key.objectid,
3760 location->objectid);
3767 leaf = path->nodes[0];
3768 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3769 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
3770 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3773 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3774 (unsigned long)(ref + 1),
3775 dentry->d_name.len);
3779 btrfs_release_path(path);
3781 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3782 if (IS_ERR(new_root)) {
3783 err = PTR_ERR(new_root);
3787 if (btrfs_root_refs(&new_root->root_item) == 0) {
3792 *sub_root = new_root;
3793 location->objectid = btrfs_root_dirid(&new_root->root_item);
3794 location->type = BTRFS_INODE_ITEM_KEY;
3795 location->offset = 0;
3798 btrfs_free_path(path);
3802 static void inode_tree_add(struct inode *inode)
3804 struct btrfs_root *root = BTRFS_I(inode)->root;
3805 struct btrfs_inode *entry;
3807 struct rb_node *parent;
3808 u64 ino = btrfs_ino(inode);
3810 p = &root->inode_tree.rb_node;
3813 if (inode_unhashed(inode))
3816 spin_lock(&root->inode_lock);
3819 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3821 if (ino < btrfs_ino(&entry->vfs_inode))
3822 p = &parent->rb_left;
3823 else if (ino > btrfs_ino(&entry->vfs_inode))
3824 p = &parent->rb_right;
3826 WARN_ON(!(entry->vfs_inode.i_state &
3827 (I_WILL_FREE | I_FREEING)));
3828 rb_erase(parent, &root->inode_tree);
3829 RB_CLEAR_NODE(parent);
3830 spin_unlock(&root->inode_lock);
3834 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3835 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3836 spin_unlock(&root->inode_lock);
3839 static void inode_tree_del(struct inode *inode)
3841 struct btrfs_root *root = BTRFS_I(inode)->root;
3844 spin_lock(&root->inode_lock);
3845 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3846 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3847 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3848 empty = RB_EMPTY_ROOT(&root->inode_tree);
3850 spin_unlock(&root->inode_lock);
3853 * Free space cache has inodes in the tree root, but the tree root has a
3854 * root_refs of 0, so this could end up dropping the tree root as a
3855 * snapshot, so we need the extra !root->fs_info->tree_root check to
3856 * make sure we don't drop it.
3858 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
3859 root != root->fs_info->tree_root) {
3860 synchronize_srcu(&root->fs_info->subvol_srcu);
3861 spin_lock(&root->inode_lock);
3862 empty = RB_EMPTY_ROOT(&root->inode_tree);
3863 spin_unlock(&root->inode_lock);
3865 btrfs_add_dead_root(root);
3869 int btrfs_invalidate_inodes(struct btrfs_root *root)
3871 struct rb_node *node;
3872 struct rb_node *prev;
3873 struct btrfs_inode *entry;
3874 struct inode *inode;
3877 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3879 spin_lock(&root->inode_lock);
3881 node = root->inode_tree.rb_node;
3885 entry = rb_entry(node, struct btrfs_inode, rb_node);
3887 if (objectid < btrfs_ino(&entry->vfs_inode))
3888 node = node->rb_left;
3889 else if (objectid > btrfs_ino(&entry->vfs_inode))
3890 node = node->rb_right;
3896 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3897 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
3901 prev = rb_next(prev);
3905 entry = rb_entry(node, struct btrfs_inode, rb_node);
3906 objectid = btrfs_ino(&entry->vfs_inode) + 1;
3907 inode = igrab(&entry->vfs_inode);
3909 spin_unlock(&root->inode_lock);
3910 if (atomic_read(&inode->i_count) > 1)
3911 d_prune_aliases(inode);
3913 * btrfs_drop_inode will have it removed from
3914 * the inode cache when its usage count
3919 spin_lock(&root->inode_lock);
3923 if (cond_resched_lock(&root->inode_lock))
3926 node = rb_next(node);
3928 spin_unlock(&root->inode_lock);
3932 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3934 struct btrfs_iget_args *args = p;
3935 inode->i_ino = args->ino;
3936 BTRFS_I(inode)->root = args->root;
3937 btrfs_set_inode_space_info(args->root, inode);
3941 static int btrfs_find_actor(struct inode *inode, void *opaque)
3943 struct btrfs_iget_args *args = opaque;
3944 return args->ino == btrfs_ino(inode) &&
3945 args->root == BTRFS_I(inode)->root;
3948 static struct inode *btrfs_iget_locked(struct super_block *s,
3950 struct btrfs_root *root)
3952 struct inode *inode;
3953 struct btrfs_iget_args args;
3954 args.ino = objectid;
3957 inode = iget5_locked(s, objectid, btrfs_find_actor,
3958 btrfs_init_locked_inode,
3963 /* Get an inode object given its location and corresponding root.
3964 * Returns in *is_new if the inode was read from disk
3966 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3967 struct btrfs_root *root, int *new)
3969 struct inode *inode;
3971 inode = btrfs_iget_locked(s, location->objectid, root);
3973 return ERR_PTR(-ENOMEM);
3975 if (inode->i_state & I_NEW) {
3976 BTRFS_I(inode)->root = root;
3977 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3978 btrfs_read_locked_inode(inode);
3979 inode_tree_add(inode);
3980 unlock_new_inode(inode);
3988 static struct inode *new_simple_dir(struct super_block *s,
3989 struct btrfs_key *key,
3990 struct btrfs_root *root)
3992 struct inode *inode = new_inode(s);
3995 return ERR_PTR(-ENOMEM);
3997 BTRFS_I(inode)->root = root;
3998 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3999 BTRFS_I(inode)->dummy_inode = 1;
4001 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
4002 inode->i_op = &simple_dir_inode_operations;
4003 inode->i_fop = &simple_dir_operations;
4004 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
4005 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4010 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
4012 struct inode *inode;
4013 struct btrfs_root *root = BTRFS_I(dir)->root;
4014 struct btrfs_root *sub_root = root;
4015 struct btrfs_key location;
4019 if (dentry->d_name.len > BTRFS_NAME_LEN)
4020 return ERR_PTR(-ENAMETOOLONG);
4022 ret = btrfs_inode_by_name(dir, dentry, &location);
4025 return ERR_PTR(ret);
4027 if (location.objectid == 0)
4030 if (location.type == BTRFS_INODE_ITEM_KEY) {
4031 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
4035 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
4037 index = srcu_read_lock(&root->fs_info->subvol_srcu);
4038 ret = fixup_tree_root_location(root, dir, dentry,
4039 &location, &sub_root);
4042 inode = ERR_PTR(ret);
4044 inode = new_simple_dir(dir->i_sb, &location, sub_root);
4046 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
4048 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
4050 if (!IS_ERR(inode) && root != sub_root) {
4051 down_read(&root->fs_info->cleanup_work_sem);
4052 if (!(inode->i_sb->s_flags & MS_RDONLY))
4053 ret = btrfs_orphan_cleanup(sub_root);
4054 up_read(&root->fs_info->cleanup_work_sem);
4056 inode = ERR_PTR(ret);
4062 static int btrfs_dentry_delete(const struct dentry *dentry)
4064 struct btrfs_root *root;
4066 if (!dentry->d_inode && !IS_ROOT(dentry))
4067 dentry = dentry->d_parent;
4069 if (dentry->d_inode) {
4070 root = BTRFS_I(dentry->d_inode)->root;
4071 if (btrfs_root_refs(&root->root_item) == 0)
4077 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
4078 struct nameidata *nd)
4080 struct inode *inode;
4082 inode = btrfs_lookup_dentry(dir, dentry);
4084 return ERR_CAST(inode);
4086 return d_splice_alias(inode, dentry);
4089 unsigned char btrfs_filetype_table[] = {
4090 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
4093 static int btrfs_real_readdir(struct file *filp, void *dirent,
4096 struct inode *inode = filp->f_dentry->d_inode;
4097 struct btrfs_root *root = BTRFS_I(inode)->root;
4098 struct btrfs_item *item;
4099 struct btrfs_dir_item *di;
4100 struct btrfs_key key;
4101 struct btrfs_key found_key;
4102 struct btrfs_path *path;
4103 struct list_head ins_list;
4104 struct list_head del_list;
4106 struct extent_buffer *leaf;
4108 unsigned char d_type;
4113 int key_type = BTRFS_DIR_INDEX_KEY;
4117 int is_curr = 0; /* filp->f_pos points to the current index? */
4119 /* FIXME, use a real flag for deciding about the key type */
4120 if (root->fs_info->tree_root == root)
4121 key_type = BTRFS_DIR_ITEM_KEY;
4123 /* special case for "." */
4124 if (filp->f_pos == 0) {
4125 over = filldir(dirent, ".", 1, 1, btrfs_ino(inode), DT_DIR);
4130 /* special case for .., just use the back ref */
4131 if (filp->f_pos == 1) {
4132 u64 pino = parent_ino(filp->f_path.dentry);
4133 over = filldir(dirent, "..", 2,
4139 path = btrfs_alloc_path();
4145 if (key_type == BTRFS_DIR_INDEX_KEY) {
4146 INIT_LIST_HEAD(&ins_list);
4147 INIT_LIST_HEAD(&del_list);
4148 btrfs_get_delayed_items(inode, &ins_list, &del_list);
4151 btrfs_set_key_type(&key, key_type);
4152 key.offset = filp->f_pos;
4153 key.objectid = btrfs_ino(inode);
4155 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4160 leaf = path->nodes[0];
4161 slot = path->slots[0];
4162 if (slot >= btrfs_header_nritems(leaf)) {
4163 ret = btrfs_next_leaf(root, path);
4171 item = btrfs_item_nr(leaf, slot);
4172 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4174 if (found_key.objectid != key.objectid)
4176 if (btrfs_key_type(&found_key) != key_type)
4178 if (found_key.offset < filp->f_pos)
4180 if (key_type == BTRFS_DIR_INDEX_KEY &&
4181 btrfs_should_delete_dir_index(&del_list,
4185 filp->f_pos = found_key.offset;
4188 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
4190 di_total = btrfs_item_size(leaf, item);
4192 while (di_cur < di_total) {
4193 struct btrfs_key location;
4195 if (verify_dir_item(root, leaf, di))
4198 name_len = btrfs_dir_name_len(leaf, di);
4199 if (name_len <= sizeof(tmp_name)) {
4200 name_ptr = tmp_name;
4202 name_ptr = kmalloc(name_len, GFP_NOFS);
4208 read_extent_buffer(leaf, name_ptr,
4209 (unsigned long)(di + 1), name_len);
4211 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
4212 btrfs_dir_item_key_to_cpu(leaf, di, &location);
4214 /* is this a reference to our own snapshot? If so
4217 if (location.type == BTRFS_ROOT_ITEM_KEY &&
4218 location.objectid == root->root_key.objectid) {
4222 over = filldir(dirent, name_ptr, name_len,
4223 found_key.offset, location.objectid,
4227 if (name_ptr != tmp_name)
4232 di_len = btrfs_dir_name_len(leaf, di) +
4233 btrfs_dir_data_len(leaf, di) + sizeof(*di);
4235 di = (struct btrfs_dir_item *)((char *)di + di_len);
4241 if (key_type == BTRFS_DIR_INDEX_KEY) {
4244 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
4250 /* Reached end of directory/root. Bump pos past the last item. */
4251 if (key_type == BTRFS_DIR_INDEX_KEY)
4253 * 32-bit glibc will use getdents64, but then strtol -
4254 * so the last number we can serve is this.
4256 filp->f_pos = 0x7fffffff;
4262 if (key_type == BTRFS_DIR_INDEX_KEY)
4263 btrfs_put_delayed_items(&ins_list, &del_list);
4264 btrfs_free_path(path);
4268 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
4270 struct btrfs_root *root = BTRFS_I(inode)->root;
4271 struct btrfs_trans_handle *trans;
4273 bool nolock = false;
4275 if (BTRFS_I(inode)->dummy_inode)
4278 if (btrfs_fs_closing(root->fs_info) && is_free_space_inode(root, inode))
4281 if (wbc->sync_mode == WB_SYNC_ALL) {
4283 trans = btrfs_join_transaction_nolock(root);
4285 trans = btrfs_join_transaction(root);
4287 return PTR_ERR(trans);
4289 ret = btrfs_end_transaction_nolock(trans, root);
4291 ret = btrfs_commit_transaction(trans, root);
4297 * This is somewhat expensive, updating the tree every time the
4298 * inode changes. But, it is most likely to find the inode in cache.
4299 * FIXME, needs more benchmarking...there are no reasons other than performance
4300 * to keep or drop this code.
4302 void btrfs_dirty_inode(struct inode *inode, int flags)
4304 struct btrfs_root *root = BTRFS_I(inode)->root;
4305 struct btrfs_trans_handle *trans;
4308 if (BTRFS_I(inode)->dummy_inode)
4311 trans = btrfs_join_transaction(root);
4312 BUG_ON(IS_ERR(trans));
4314 ret = btrfs_update_inode(trans, root, inode);
4315 if (ret && ret == -ENOSPC) {
4316 /* whoops, lets try again with the full transaction */
4317 btrfs_end_transaction(trans, root);
4318 trans = btrfs_start_transaction(root, 1);
4319 if (IS_ERR(trans)) {
4320 printk_ratelimited(KERN_ERR "btrfs: fail to "
4321 "dirty inode %llu error %ld\n",
4322 (unsigned long long)btrfs_ino(inode),
4327 ret = btrfs_update_inode(trans, root, inode);
4329 printk_ratelimited(KERN_ERR "btrfs: fail to "
4330 "dirty inode %llu error %d\n",
4331 (unsigned long long)btrfs_ino(inode),
4335 btrfs_end_transaction(trans, root);
4336 if (BTRFS_I(inode)->delayed_node)
4337 btrfs_balance_delayed_items(root);
4341 * find the highest existing sequence number in a directory
4342 * and then set the in-memory index_cnt variable to reflect
4343 * free sequence numbers
4345 static int btrfs_set_inode_index_count(struct inode *inode)
4347 struct btrfs_root *root = BTRFS_I(inode)->root;
4348 struct btrfs_key key, found_key;
4349 struct btrfs_path *path;
4350 struct extent_buffer *leaf;
4353 key.objectid = btrfs_ino(inode);
4354 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4355 key.offset = (u64)-1;
4357 path = btrfs_alloc_path();
4361 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4364 /* FIXME: we should be able to handle this */
4370 * MAGIC NUMBER EXPLANATION:
4371 * since we search a directory based on f_pos we have to start at 2
4372 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4373 * else has to start at 2
4375 if (path->slots[0] == 0) {
4376 BTRFS_I(inode)->index_cnt = 2;
4382 leaf = path->nodes[0];
4383 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4385 if (found_key.objectid != btrfs_ino(inode) ||
4386 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4387 BTRFS_I(inode)->index_cnt = 2;
4391 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4393 btrfs_free_path(path);
4398 * helper to find a free sequence number in a given directory. This current
4399 * code is very simple, later versions will do smarter things in the btree
4401 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4405 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4406 ret = btrfs_inode_delayed_dir_index_count(dir);
4408 ret = btrfs_set_inode_index_count(dir);
4414 *index = BTRFS_I(dir)->index_cnt;
4415 BTRFS_I(dir)->index_cnt++;
4420 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4421 struct btrfs_root *root,
4423 const char *name, int name_len,
4424 u64 ref_objectid, u64 objectid, int mode,
4427 struct inode *inode;
4428 struct btrfs_inode_item *inode_item;
4429 struct btrfs_key *location;
4430 struct btrfs_path *path;
4431 struct btrfs_inode_ref *ref;
4432 struct btrfs_key key[2];
4438 path = btrfs_alloc_path();
4441 inode = new_inode(root->fs_info->sb);
4443 btrfs_free_path(path);
4444 return ERR_PTR(-ENOMEM);
4448 * we have to initialize this early, so we can reclaim the inode
4449 * number if we fail afterwards in this function.
4451 inode->i_ino = objectid;
4454 trace_btrfs_inode_request(dir);
4456 ret = btrfs_set_inode_index(dir, index);
4458 btrfs_free_path(path);
4460 return ERR_PTR(ret);
4464 * index_cnt is ignored for everything but a dir,
4465 * btrfs_get_inode_index_count has an explanation for the magic
4468 BTRFS_I(inode)->index_cnt = 2;
4469 BTRFS_I(inode)->root = root;
4470 BTRFS_I(inode)->generation = trans->transid;
4471 inode->i_generation = BTRFS_I(inode)->generation;
4472 btrfs_set_inode_space_info(root, inode);
4479 key[0].objectid = objectid;
4480 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4483 key[1].objectid = objectid;
4484 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4485 key[1].offset = ref_objectid;
4487 sizes[0] = sizeof(struct btrfs_inode_item);
4488 sizes[1] = name_len + sizeof(*ref);
4490 path->leave_spinning = 1;
4491 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4495 inode_init_owner(inode, dir, mode);
4496 inode_set_bytes(inode, 0);
4497 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4498 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4499 struct btrfs_inode_item);
4500 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4502 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4503 struct btrfs_inode_ref);
4504 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4505 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4506 ptr = (unsigned long)(ref + 1);
4507 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4509 btrfs_mark_buffer_dirty(path->nodes[0]);
4510 btrfs_free_path(path);
4512 location = &BTRFS_I(inode)->location;
4513 location->objectid = objectid;
4514 location->offset = 0;
4515 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4517 btrfs_inherit_iflags(inode, dir);
4519 if ((mode & S_IFREG)) {
4520 if (btrfs_test_opt(root, NODATASUM))
4521 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4522 if (btrfs_test_opt(root, NODATACOW) ||
4523 (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
4524 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4527 insert_inode_hash(inode);
4528 inode_tree_add(inode);
4530 trace_btrfs_inode_new(inode);
4531 btrfs_set_inode_last_trans(trans, inode);
4536 BTRFS_I(dir)->index_cnt--;
4537 btrfs_free_path(path);
4539 return ERR_PTR(ret);
4542 static inline u8 btrfs_inode_type(struct inode *inode)
4544 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4548 * utility function to add 'inode' into 'parent_inode' with
4549 * a give name and a given sequence number.
4550 * if 'add_backref' is true, also insert a backref from the
4551 * inode to the parent directory.
4553 int btrfs_add_link(struct btrfs_trans_handle *trans,
4554 struct inode *parent_inode, struct inode *inode,
4555 const char *name, int name_len, int add_backref, u64 index)
4558 struct btrfs_key key;
4559 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4560 u64 ino = btrfs_ino(inode);
4561 u64 parent_ino = btrfs_ino(parent_inode);
4563 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4564 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4567 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4571 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4572 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4573 key.objectid, root->root_key.objectid,
4574 parent_ino, index, name, name_len);
4575 } else if (add_backref) {
4576 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
4581 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4583 btrfs_inode_type(inode), index);
4586 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4588 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4589 ret = btrfs_update_inode(trans, root, parent_inode);
4594 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4595 struct inode *dir, struct dentry *dentry,
4596 struct inode *inode, int backref, u64 index)
4598 int err = btrfs_add_link(trans, dir, inode,
4599 dentry->d_name.name, dentry->d_name.len,
4602 d_instantiate(dentry, inode);
4610 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4611 int mode, dev_t rdev)
4613 struct btrfs_trans_handle *trans;
4614 struct btrfs_root *root = BTRFS_I(dir)->root;
4615 struct inode *inode = NULL;
4619 unsigned long nr = 0;
4622 if (!new_valid_dev(rdev))
4626 * 2 for inode item and ref
4628 * 1 for xattr if selinux is on
4630 trans = btrfs_start_transaction(root, 5);
4632 return PTR_ERR(trans);
4634 err = btrfs_find_free_ino(root, &objectid);
4638 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4639 dentry->d_name.len, btrfs_ino(dir), objectid,
4641 if (IS_ERR(inode)) {
4642 err = PTR_ERR(inode);
4646 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4652 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4656 inode->i_op = &btrfs_special_inode_operations;
4657 init_special_inode(inode, inode->i_mode, rdev);
4658 btrfs_update_inode(trans, root, inode);
4661 nr = trans->blocks_used;
4662 btrfs_end_transaction_throttle(trans, root);
4663 btrfs_btree_balance_dirty(root, nr);
4665 inode_dec_link_count(inode);
4671 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4672 int mode, struct nameidata *nd)
4674 struct btrfs_trans_handle *trans;
4675 struct btrfs_root *root = BTRFS_I(dir)->root;
4676 struct inode *inode = NULL;
4679 unsigned long nr = 0;
4684 * 2 for inode item and ref
4686 * 1 for xattr if selinux is on
4688 trans = btrfs_start_transaction(root, 5);
4690 return PTR_ERR(trans);
4692 err = btrfs_find_free_ino(root, &objectid);
4696 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4697 dentry->d_name.len, btrfs_ino(dir), objectid,
4699 if (IS_ERR(inode)) {
4700 err = PTR_ERR(inode);
4704 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4710 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4714 inode->i_mapping->a_ops = &btrfs_aops;
4715 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4716 inode->i_fop = &btrfs_file_operations;
4717 inode->i_op = &btrfs_file_inode_operations;
4718 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4721 nr = trans->blocks_used;
4722 btrfs_end_transaction_throttle(trans, root);
4724 inode_dec_link_count(inode);
4727 btrfs_btree_balance_dirty(root, nr);
4731 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4732 struct dentry *dentry)
4734 struct btrfs_trans_handle *trans;
4735 struct btrfs_root *root = BTRFS_I(dir)->root;
4736 struct inode *inode = old_dentry->d_inode;
4738 unsigned long nr = 0;
4742 /* do not allow sys_link's with other subvols of the same device */
4743 if (root->objectid != BTRFS_I(inode)->root->objectid)
4746 if (inode->i_nlink == ~0U)
4749 err = btrfs_set_inode_index(dir, &index);
4754 * 2 items for inode and inode ref
4755 * 2 items for dir items
4756 * 1 item for parent inode
4758 trans = btrfs_start_transaction(root, 5);
4759 if (IS_ERR(trans)) {
4760 err = PTR_ERR(trans);
4764 btrfs_inc_nlink(inode);
4765 inode->i_ctime = CURRENT_TIME;
4768 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
4773 struct dentry *parent = dget_parent(dentry);
4774 err = btrfs_update_inode(trans, root, inode);
4776 btrfs_log_new_name(trans, inode, NULL, parent);
4780 nr = trans->blocks_used;
4781 btrfs_end_transaction_throttle(trans, root);
4784 inode_dec_link_count(inode);
4787 btrfs_btree_balance_dirty(root, nr);
4791 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4793 struct inode *inode = NULL;
4794 struct btrfs_trans_handle *trans;
4795 struct btrfs_root *root = BTRFS_I(dir)->root;
4797 int drop_on_err = 0;
4800 unsigned long nr = 1;
4803 * 2 items for inode and ref
4804 * 2 items for dir items
4805 * 1 for xattr if selinux is on
4807 trans = btrfs_start_transaction(root, 5);
4809 return PTR_ERR(trans);
4811 err = btrfs_find_free_ino(root, &objectid);
4815 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4816 dentry->d_name.len, btrfs_ino(dir), objectid,
4817 S_IFDIR | mode, &index);
4818 if (IS_ERR(inode)) {
4819 err = PTR_ERR(inode);
4825 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4829 inode->i_op = &btrfs_dir_inode_operations;
4830 inode->i_fop = &btrfs_dir_file_operations;
4832 btrfs_i_size_write(inode, 0);
4833 err = btrfs_update_inode(trans, root, inode);
4837 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
4838 dentry->d_name.len, 0, index);
4842 d_instantiate(dentry, inode);
4846 nr = trans->blocks_used;
4847 btrfs_end_transaction_throttle(trans, root);
4850 btrfs_btree_balance_dirty(root, nr);
4854 /* helper for btfs_get_extent. Given an existing extent in the tree,
4855 * and an extent that you want to insert, deal with overlap and insert
4856 * the new extent into the tree.
4858 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4859 struct extent_map *existing,
4860 struct extent_map *em,
4861 u64 map_start, u64 map_len)
4865 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4866 start_diff = map_start - em->start;
4867 em->start = map_start;
4869 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4870 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4871 em->block_start += start_diff;
4872 em->block_len -= start_diff;
4874 return add_extent_mapping(em_tree, em);
4877 static noinline int uncompress_inline(struct btrfs_path *path,
4878 struct inode *inode, struct page *page,
4879 size_t pg_offset, u64 extent_offset,
4880 struct btrfs_file_extent_item *item)
4883 struct extent_buffer *leaf = path->nodes[0];
4886 unsigned long inline_size;
4890 WARN_ON(pg_offset != 0);
4891 compress_type = btrfs_file_extent_compression(leaf, item);
4892 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4893 inline_size = btrfs_file_extent_inline_item_len(leaf,
4894 btrfs_item_nr(leaf, path->slots[0]));
4895 tmp = kmalloc(inline_size, GFP_NOFS);
4898 ptr = btrfs_file_extent_inline_start(item);
4900 read_extent_buffer(leaf, tmp, ptr, inline_size);
4902 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4903 ret = btrfs_decompress(compress_type, tmp, page,
4904 extent_offset, inline_size, max_size);
4906 char *kaddr = kmap_atomic(page, KM_USER0);
4907 unsigned long copy_size = min_t(u64,
4908 PAGE_CACHE_SIZE - pg_offset,
4909 max_size - extent_offset);
4910 memset(kaddr + pg_offset, 0, copy_size);
4911 kunmap_atomic(kaddr, KM_USER0);
4918 * a bit scary, this does extent mapping from logical file offset to the disk.
4919 * the ugly parts come from merging extents from the disk with the in-ram
4920 * representation. This gets more complex because of the data=ordered code,
4921 * where the in-ram extents might be locked pending data=ordered completion.
4923 * This also copies inline extents directly into the page.
4926 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4927 size_t pg_offset, u64 start, u64 len,
4933 u64 extent_start = 0;
4935 u64 objectid = btrfs_ino(inode);
4937 struct btrfs_path *path = NULL;
4938 struct btrfs_root *root = BTRFS_I(inode)->root;
4939 struct btrfs_file_extent_item *item;
4940 struct extent_buffer *leaf;
4941 struct btrfs_key found_key;
4942 struct extent_map *em = NULL;
4943 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4944 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4945 struct btrfs_trans_handle *trans = NULL;
4949 read_lock(&em_tree->lock);
4950 em = lookup_extent_mapping(em_tree, start, len);
4952 em->bdev = root->fs_info->fs_devices->latest_bdev;
4953 read_unlock(&em_tree->lock);
4956 if (em->start > start || em->start + em->len <= start)
4957 free_extent_map(em);
4958 else if (em->block_start == EXTENT_MAP_INLINE && page)
4959 free_extent_map(em);
4963 em = alloc_extent_map();
4968 em->bdev = root->fs_info->fs_devices->latest_bdev;
4969 em->start = EXTENT_MAP_HOLE;
4970 em->orig_start = EXTENT_MAP_HOLE;
4972 em->block_len = (u64)-1;
4975 path = btrfs_alloc_path();
4981 * Chances are we'll be called again, so go ahead and do
4987 ret = btrfs_lookup_file_extent(trans, root, path,
4988 objectid, start, trans != NULL);
4995 if (path->slots[0] == 0)
5000 leaf = path->nodes[0];
5001 item = btrfs_item_ptr(leaf, path->slots[0],
5002 struct btrfs_file_extent_item);
5003 /* are we inside the extent that was found? */
5004 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5005 found_type = btrfs_key_type(&found_key);
5006 if (found_key.objectid != objectid ||
5007 found_type != BTRFS_EXTENT_DATA_KEY) {
5011 found_type = btrfs_file_extent_type(leaf, item);
5012 extent_start = found_key.offset;
5013 compress_type = btrfs_file_extent_compression(leaf, item);
5014 if (found_type == BTRFS_FILE_EXTENT_REG ||
5015 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5016 extent_end = extent_start +
5017 btrfs_file_extent_num_bytes(leaf, item);
5018 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5020 size = btrfs_file_extent_inline_len(leaf, item);
5021 extent_end = (extent_start + size + root->sectorsize - 1) &
5022 ~((u64)root->sectorsize - 1);
5025 if (start >= extent_end) {
5027 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
5028 ret = btrfs_next_leaf(root, path);
5035 leaf = path->nodes[0];
5037 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5038 if (found_key.objectid != objectid ||
5039 found_key.type != BTRFS_EXTENT_DATA_KEY)
5041 if (start + len <= found_key.offset)
5044 em->len = found_key.offset - start;
5048 if (found_type == BTRFS_FILE_EXTENT_REG ||
5049 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5050 em->start = extent_start;
5051 em->len = extent_end - extent_start;
5052 em->orig_start = extent_start -
5053 btrfs_file_extent_offset(leaf, item);
5054 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
5056 em->block_start = EXTENT_MAP_HOLE;
5059 if (compress_type != BTRFS_COMPRESS_NONE) {
5060 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5061 em->compress_type = compress_type;
5062 em->block_start = bytenr;
5063 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
5066 bytenr += btrfs_file_extent_offset(leaf, item);
5067 em->block_start = bytenr;
5068 em->block_len = em->len;
5069 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
5070 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
5073 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5077 size_t extent_offset;
5080 em->block_start = EXTENT_MAP_INLINE;
5081 if (!page || create) {
5082 em->start = extent_start;
5083 em->len = extent_end - extent_start;
5087 size = btrfs_file_extent_inline_len(leaf, item);
5088 extent_offset = page_offset(page) + pg_offset - extent_start;
5089 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
5090 size - extent_offset);
5091 em->start = extent_start + extent_offset;
5092 em->len = (copy_size + root->sectorsize - 1) &
5093 ~((u64)root->sectorsize - 1);
5094 em->orig_start = EXTENT_MAP_INLINE;
5095 if (compress_type) {
5096 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5097 em->compress_type = compress_type;
5099 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
5100 if (create == 0 && !PageUptodate(page)) {
5101 if (btrfs_file_extent_compression(leaf, item) !=
5102 BTRFS_COMPRESS_NONE) {
5103 ret = uncompress_inline(path, inode, page,
5105 extent_offset, item);
5109 read_extent_buffer(leaf, map + pg_offset, ptr,
5111 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
5112 memset(map + pg_offset + copy_size, 0,
5113 PAGE_CACHE_SIZE - pg_offset -
5118 flush_dcache_page(page);
5119 } else if (create && PageUptodate(page)) {
5123 free_extent_map(em);
5126 btrfs_release_path(path);
5127 trans = btrfs_join_transaction(root);
5130 return ERR_CAST(trans);
5134 write_extent_buffer(leaf, map + pg_offset, ptr,
5137 btrfs_mark_buffer_dirty(leaf);
5139 set_extent_uptodate(io_tree, em->start,
5140 extent_map_end(em) - 1, NULL, GFP_NOFS);
5143 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
5150 em->block_start = EXTENT_MAP_HOLE;
5151 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
5153 btrfs_release_path(path);
5154 if (em->start > start || extent_map_end(em) <= start) {
5155 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
5156 "[%llu %llu]\n", (unsigned long long)em->start,
5157 (unsigned long long)em->len,
5158 (unsigned long long)start,
5159 (unsigned long long)len);
5165 write_lock(&em_tree->lock);
5166 ret = add_extent_mapping(em_tree, em);
5167 /* it is possible that someone inserted the extent into the tree
5168 * while we had the lock dropped. It is also possible that
5169 * an overlapping map exists in the tree
5171 if (ret == -EEXIST) {
5172 struct extent_map *existing;
5176 existing = lookup_extent_mapping(em_tree, start, len);
5177 if (existing && (existing->start > start ||
5178 existing->start + existing->len <= start)) {
5179 free_extent_map(existing);
5183 existing = lookup_extent_mapping(em_tree, em->start,
5186 err = merge_extent_mapping(em_tree, existing,
5189 free_extent_map(existing);
5191 free_extent_map(em);
5196 free_extent_map(em);
5200 free_extent_map(em);
5205 write_unlock(&em_tree->lock);
5208 trace_btrfs_get_extent(root, em);
5211 btrfs_free_path(path);
5213 ret = btrfs_end_transaction(trans, root);
5218 free_extent_map(em);
5219 return ERR_PTR(err);
5224 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
5225 size_t pg_offset, u64 start, u64 len,
5228 struct extent_map *em;
5229 struct extent_map *hole_em = NULL;
5230 u64 range_start = start;
5236 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
5241 * if our em maps to a hole, there might
5242 * actually be delalloc bytes behind it
5244 if (em->block_start != EXTENT_MAP_HOLE)
5250 /* check to see if we've wrapped (len == -1 or similar) */
5259 /* ok, we didn't find anything, lets look for delalloc */
5260 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
5261 end, len, EXTENT_DELALLOC, 1);
5262 found_end = range_start + found;
5263 if (found_end < range_start)
5264 found_end = (u64)-1;
5267 * we didn't find anything useful, return
5268 * the original results from get_extent()
5270 if (range_start > end || found_end <= start) {
5276 /* adjust the range_start to make sure it doesn't
5277 * go backwards from the start they passed in
5279 range_start = max(start,range_start);
5280 found = found_end - range_start;
5283 u64 hole_start = start;
5286 em = alloc_extent_map();
5292 * when btrfs_get_extent can't find anything it
5293 * returns one huge hole
5295 * make sure what it found really fits our range, and
5296 * adjust to make sure it is based on the start from
5300 u64 calc_end = extent_map_end(hole_em);
5302 if (calc_end <= start || (hole_em->start > end)) {
5303 free_extent_map(hole_em);
5306 hole_start = max(hole_em->start, start);
5307 hole_len = calc_end - hole_start;
5311 if (hole_em && range_start > hole_start) {
5312 /* our hole starts before our delalloc, so we
5313 * have to return just the parts of the hole
5314 * that go until the delalloc starts
5316 em->len = min(hole_len,
5317 range_start - hole_start);
5318 em->start = hole_start;
5319 em->orig_start = hole_start;
5321 * don't adjust block start at all,
5322 * it is fixed at EXTENT_MAP_HOLE
5324 em->block_start = hole_em->block_start;
5325 em->block_len = hole_len;
5327 em->start = range_start;
5329 em->orig_start = range_start;
5330 em->block_start = EXTENT_MAP_DELALLOC;
5331 em->block_len = found;
5333 } else if (hole_em) {
5338 free_extent_map(hole_em);
5340 free_extent_map(em);
5341 return ERR_PTR(err);
5346 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
5347 struct extent_map *em,
5350 struct btrfs_root *root = BTRFS_I(inode)->root;
5351 struct btrfs_trans_handle *trans;
5352 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5353 struct btrfs_key ins;
5356 bool insert = false;
5359 * Ok if the extent map we looked up is a hole and is for the exact
5360 * range we want, there is no reason to allocate a new one, however if
5361 * it is not right then we need to free this one and drop the cache for
5364 if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
5366 free_extent_map(em);
5369 btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
5372 trans = btrfs_join_transaction(root);
5374 return ERR_CAST(trans);
5376 if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024)
5377 btrfs_add_inode_defrag(trans, inode);
5379 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5381 alloc_hint = get_extent_allocation_hint(inode, start, len);
5382 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
5383 alloc_hint, (u64)-1, &ins, 1);
5390 em = alloc_extent_map();
5392 em = ERR_PTR(-ENOMEM);
5398 em->orig_start = em->start;
5399 em->len = ins.offset;
5401 em->block_start = ins.objectid;
5402 em->block_len = ins.offset;
5403 em->bdev = root->fs_info->fs_devices->latest_bdev;
5406 * We need to do this because if we're using the original em we searched
5407 * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
5410 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5413 write_lock(&em_tree->lock);
5414 ret = add_extent_mapping(em_tree, em);
5415 write_unlock(&em_tree->lock);
5418 btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
5421 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
5422 ins.offset, ins.offset, 0);
5424 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
5428 btrfs_end_transaction(trans, root);
5433 * returns 1 when the nocow is safe, < 1 on error, 0 if the
5434 * block must be cow'd
5436 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
5437 struct inode *inode, u64 offset, u64 len)
5439 struct btrfs_path *path;
5441 struct extent_buffer *leaf;
5442 struct btrfs_root *root = BTRFS_I(inode)->root;
5443 struct btrfs_file_extent_item *fi;
5444 struct btrfs_key key;
5452 path = btrfs_alloc_path();
5456 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
5461 slot = path->slots[0];
5464 /* can't find the item, must cow */
5471 leaf = path->nodes[0];
5472 btrfs_item_key_to_cpu(leaf, &key, slot);
5473 if (key.objectid != btrfs_ino(inode) ||
5474 key.type != BTRFS_EXTENT_DATA_KEY) {
5475 /* not our file or wrong item type, must cow */
5479 if (key.offset > offset) {
5480 /* Wrong offset, must cow */
5484 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5485 found_type = btrfs_file_extent_type(leaf, fi);
5486 if (found_type != BTRFS_FILE_EXTENT_REG &&
5487 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
5488 /* not a regular extent, must cow */
5491 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5492 backref_offset = btrfs_file_extent_offset(leaf, fi);
5494 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
5495 if (extent_end < offset + len) {
5496 /* extent doesn't include our full range, must cow */
5500 if (btrfs_extent_readonly(root, disk_bytenr))
5504 * look for other files referencing this extent, if we
5505 * find any we must cow
5507 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
5508 key.offset - backref_offset, disk_bytenr))
5512 * adjust disk_bytenr and num_bytes to cover just the bytes
5513 * in this extent we are about to write. If there
5514 * are any csums in that range we have to cow in order
5515 * to keep the csums correct
5517 disk_bytenr += backref_offset;
5518 disk_bytenr += offset - key.offset;
5519 num_bytes = min(offset + len, extent_end) - offset;
5520 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
5523 * all of the above have passed, it is safe to overwrite this extent
5528 btrfs_free_path(path);
5532 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
5533 struct buffer_head *bh_result, int create)
5535 struct extent_map *em;
5536 struct btrfs_root *root = BTRFS_I(inode)->root;
5537 u64 start = iblock << inode->i_blkbits;
5538 u64 len = bh_result->b_size;
5539 struct btrfs_trans_handle *trans;
5541 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
5546 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
5547 * io. INLINE is special, and we could probably kludge it in here, but
5548 * it's still buffered so for safety lets just fall back to the generic
5551 * For COMPRESSED we _have_ to read the entire extent in so we can
5552 * decompress it, so there will be buffering required no matter what we
5553 * do, so go ahead and fallback to buffered.
5555 * We return -ENOTBLK because thats what makes DIO go ahead and go back
5556 * to buffered IO. Don't blame me, this is the price we pay for using
5559 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
5560 em->block_start == EXTENT_MAP_INLINE) {
5561 free_extent_map(em);
5565 /* Just a good old fashioned hole, return */
5566 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
5567 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5568 free_extent_map(em);
5569 /* DIO will do one hole at a time, so just unlock a sector */
5570 unlock_extent(&BTRFS_I(inode)->io_tree, start,
5571 start + root->sectorsize - 1, GFP_NOFS);
5576 * We don't allocate a new extent in the following cases
5578 * 1) The inode is marked as NODATACOW. In this case we'll just use the
5580 * 2) The extent is marked as PREALLOC. We're good to go here and can
5581 * just use the extent.
5585 len = em->len - (start - em->start);
5589 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
5590 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
5591 em->block_start != EXTENT_MAP_HOLE)) {
5596 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5597 type = BTRFS_ORDERED_PREALLOC;
5599 type = BTRFS_ORDERED_NOCOW;
5600 len = min(len, em->len - (start - em->start));
5601 block_start = em->block_start + (start - em->start);
5604 * we're not going to log anything, but we do need
5605 * to make sure the current transaction stays open
5606 * while we look for nocow cross refs
5608 trans = btrfs_join_transaction(root);
5612 if (can_nocow_odirect(trans, inode, start, len) == 1) {
5613 ret = btrfs_add_ordered_extent_dio(inode, start,
5614 block_start, len, len, type);
5615 btrfs_end_transaction(trans, root);
5617 free_extent_map(em);
5622 btrfs_end_transaction(trans, root);
5626 * this will cow the extent, reset the len in case we changed
5629 len = bh_result->b_size;
5630 em = btrfs_new_extent_direct(inode, em, start, len);
5633 len = min(len, em->len - (start - em->start));
5635 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1,
5636 EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1,
5639 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
5641 bh_result->b_size = len;
5642 bh_result->b_bdev = em->bdev;
5643 set_buffer_mapped(bh_result);
5644 if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5645 set_buffer_new(bh_result);
5647 free_extent_map(em);
5652 struct btrfs_dio_private {
5653 struct inode *inode;
5660 /* number of bios pending for this dio */
5661 atomic_t pending_bios;
5666 struct bio *orig_bio;
5669 static void btrfs_endio_direct_read(struct bio *bio, int err)
5671 struct btrfs_dio_private *dip = bio->bi_private;
5672 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
5673 struct bio_vec *bvec = bio->bi_io_vec;
5674 struct inode *inode = dip->inode;
5675 struct btrfs_root *root = BTRFS_I(inode)->root;
5677 u32 *private = dip->csums;
5679 start = dip->logical_offset;
5681 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
5682 struct page *page = bvec->bv_page;
5685 unsigned long flags;
5687 local_irq_save(flags);
5688 kaddr = kmap_atomic(page, KM_IRQ0);
5689 csum = btrfs_csum_data(root, kaddr + bvec->bv_offset,
5690 csum, bvec->bv_len);
5691 btrfs_csum_final(csum, (char *)&csum);
5692 kunmap_atomic(kaddr, KM_IRQ0);
5693 local_irq_restore(flags);
5695 flush_dcache_page(bvec->bv_page);
5696 if (csum != *private) {
5697 printk(KERN_ERR "btrfs csum failed ino %llu off"
5698 " %llu csum %u private %u\n",
5699 (unsigned long long)btrfs_ino(inode),
5700 (unsigned long long)start,
5706 start += bvec->bv_len;
5709 } while (bvec <= bvec_end);
5711 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
5712 dip->logical_offset + dip->bytes - 1, GFP_NOFS);
5713 bio->bi_private = dip->private;
5718 /* If we had a csum failure make sure to clear the uptodate flag */
5720 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5721 dio_end_io(bio, err);
5724 static void btrfs_endio_direct_write(struct bio *bio, int err)
5726 struct btrfs_dio_private *dip = bio->bi_private;
5727 struct inode *inode = dip->inode;
5728 struct btrfs_root *root = BTRFS_I(inode)->root;
5729 struct btrfs_trans_handle *trans;
5730 struct btrfs_ordered_extent *ordered = NULL;
5731 struct extent_state *cached_state = NULL;
5732 u64 ordered_offset = dip->logical_offset;
5733 u64 ordered_bytes = dip->bytes;
5739 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
5747 trans = btrfs_join_transaction(root);
5748 if (IS_ERR(trans)) {
5752 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5754 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
5755 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5757 ret = btrfs_update_inode(trans, root, inode);
5762 lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5763 ordered->file_offset + ordered->len - 1, 0,
5764 &cached_state, GFP_NOFS);
5766 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) {
5767 ret = btrfs_mark_extent_written(trans, inode,
5768 ordered->file_offset,
5769 ordered->file_offset +
5776 ret = insert_reserved_file_extent(trans, inode,
5777 ordered->file_offset,
5783 BTRFS_FILE_EXTENT_REG);
5784 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
5785 ordered->file_offset, ordered->len);
5793 add_pending_csums(trans, inode, ordered->file_offset, &ordered->list);
5794 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5796 btrfs_update_inode(trans, root, inode);
5799 unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5800 ordered->file_offset + ordered->len - 1,
5801 &cached_state, GFP_NOFS);
5803 btrfs_delalloc_release_metadata(inode, ordered->len);
5804 btrfs_end_transaction(trans, root);
5805 ordered_offset = ordered->file_offset + ordered->len;
5806 btrfs_put_ordered_extent(ordered);
5807 btrfs_put_ordered_extent(ordered);
5811 * our bio might span multiple ordered extents. If we haven't
5812 * completed the accounting for the whole dio, go back and try again
5814 if (ordered_offset < dip->logical_offset + dip->bytes) {
5815 ordered_bytes = dip->logical_offset + dip->bytes -
5820 bio->bi_private = dip->private;
5825 /* If we had an error make sure to clear the uptodate flag */
5827 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5828 dio_end_io(bio, err);
5831 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
5832 struct bio *bio, int mirror_num,
5833 unsigned long bio_flags, u64 offset)
5836 struct btrfs_root *root = BTRFS_I(inode)->root;
5837 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
5842 static void btrfs_end_dio_bio(struct bio *bio, int err)
5844 struct btrfs_dio_private *dip = bio->bi_private;
5847 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
5848 "sector %#Lx len %u err no %d\n",
5849 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
5850 (unsigned long long)bio->bi_sector, bio->bi_size, err);
5854 * before atomic variable goto zero, we must make sure
5855 * dip->errors is perceived to be set.
5857 smp_mb__before_atomic_dec();
5860 /* if there are more bios still pending for this dio, just exit */
5861 if (!atomic_dec_and_test(&dip->pending_bios))
5865 bio_io_error(dip->orig_bio);
5867 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
5868 bio_endio(dip->orig_bio, 0);
5874 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
5875 u64 first_sector, gfp_t gfp_flags)
5877 int nr_vecs = bio_get_nr_vecs(bdev);
5878 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
5881 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
5882 int rw, u64 file_offset, int skip_sum,
5883 u32 *csums, int async_submit)
5885 int write = rw & REQ_WRITE;
5886 struct btrfs_root *root = BTRFS_I(inode)->root;
5890 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
5897 if (write && async_submit) {
5898 ret = btrfs_wq_submit_bio(root->fs_info,
5899 inode, rw, bio, 0, 0,
5901 __btrfs_submit_bio_start_direct_io,
5902 __btrfs_submit_bio_done);
5906 * If we aren't doing async submit, calculate the csum of the
5909 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
5912 } else if (!skip_sum) {
5913 ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
5914 file_offset, csums);
5920 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
5926 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
5929 struct inode *inode = dip->inode;
5930 struct btrfs_root *root = BTRFS_I(inode)->root;
5931 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5933 struct bio *orig_bio = dip->orig_bio;
5934 struct bio_vec *bvec = orig_bio->bi_io_vec;
5935 u64 start_sector = orig_bio->bi_sector;
5936 u64 file_offset = dip->logical_offset;
5940 u32 *csums = dip->csums;
5942 int async_submit = 0;
5943 int write = rw & REQ_WRITE;
5945 map_length = orig_bio->bi_size;
5946 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5947 &map_length, NULL, 0);
5953 if (map_length >= orig_bio->bi_size) {
5959 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
5962 bio->bi_private = dip;
5963 bio->bi_end_io = btrfs_end_dio_bio;
5964 atomic_inc(&dip->pending_bios);
5966 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
5967 if (unlikely(map_length < submit_len + bvec->bv_len ||
5968 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5969 bvec->bv_offset) < bvec->bv_len)) {
5971 * inc the count before we submit the bio so
5972 * we know the end IO handler won't happen before
5973 * we inc the count. Otherwise, the dip might get freed
5974 * before we're done setting it up
5976 atomic_inc(&dip->pending_bios);
5977 ret = __btrfs_submit_dio_bio(bio, inode, rw,
5978 file_offset, skip_sum,
5979 csums, async_submit);
5982 atomic_dec(&dip->pending_bios);
5986 /* Write's use the ordered csums */
5987 if (!write && !skip_sum)
5988 csums = csums + nr_pages;
5989 start_sector += submit_len >> 9;
5990 file_offset += submit_len;
5995 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
5996 start_sector, GFP_NOFS);
5999 bio->bi_private = dip;
6000 bio->bi_end_io = btrfs_end_dio_bio;
6002 map_length = orig_bio->bi_size;
6003 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
6004 &map_length, NULL, 0);
6010 submit_len += bvec->bv_len;
6017 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
6018 csums, async_submit);
6026 * before atomic variable goto zero, we must
6027 * make sure dip->errors is perceived to be set.
6029 smp_mb__before_atomic_dec();
6030 if (atomic_dec_and_test(&dip->pending_bios))
6031 bio_io_error(dip->orig_bio);
6033 /* bio_end_io() will handle error, so we needn't return it */
6037 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
6040 struct btrfs_root *root = BTRFS_I(inode)->root;
6041 struct btrfs_dio_private *dip;
6042 struct bio_vec *bvec = bio->bi_io_vec;
6044 int write = rw & REQ_WRITE;
6047 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
6049 dip = kmalloc(sizeof(*dip), GFP_NOFS);
6056 /* Write's use the ordered csum stuff, so we don't need dip->csums */
6057 if (!write && !skip_sum) {
6058 dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS);
6066 dip->private = bio->bi_private;
6068 dip->logical_offset = file_offset;
6072 dip->bytes += bvec->bv_len;
6074 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
6076 dip->disk_bytenr = (u64)bio->bi_sector << 9;
6077 bio->bi_private = dip;
6079 dip->orig_bio = bio;
6080 atomic_set(&dip->pending_bios, 0);
6083 bio->bi_end_io = btrfs_endio_direct_write;
6085 bio->bi_end_io = btrfs_endio_direct_read;
6087 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
6092 * If this is a write, we need to clean up the reserved space and kill
6093 * the ordered extent.
6096 struct btrfs_ordered_extent *ordered;
6097 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
6098 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
6099 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
6100 btrfs_free_reserved_extent(root, ordered->start,
6102 btrfs_put_ordered_extent(ordered);
6103 btrfs_put_ordered_extent(ordered);
6105 bio_endio(bio, ret);
6108 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
6109 const struct iovec *iov, loff_t offset,
6110 unsigned long nr_segs)
6116 unsigned blocksize_mask = root->sectorsize - 1;
6117 ssize_t retval = -EINVAL;
6118 loff_t end = offset;
6120 if (offset & blocksize_mask)
6123 /* Check the memory alignment. Blocks cannot straddle pages */
6124 for (seg = 0; seg < nr_segs; seg++) {
6125 addr = (unsigned long)iov[seg].iov_base;
6126 size = iov[seg].iov_len;
6128 if ((addr & blocksize_mask) || (size & blocksize_mask))
6131 /* If this is a write we don't need to check anymore */
6136 * Check to make sure we don't have duplicate iov_base's in this
6137 * iovec, if so return EINVAL, otherwise we'll get csum errors
6138 * when reading back.
6140 for (i = seg + 1; i < nr_segs; i++) {
6141 if (iov[seg].iov_base == iov[i].iov_base)
6149 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
6150 const struct iovec *iov, loff_t offset,
6151 unsigned long nr_segs)
6153 struct file *file = iocb->ki_filp;
6154 struct inode *inode = file->f_mapping->host;
6155 struct btrfs_ordered_extent *ordered;
6156 struct extent_state *cached_state = NULL;
6157 u64 lockstart, lockend;
6159 int writing = rw & WRITE;
6161 size_t count = iov_length(iov, nr_segs);
6163 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
6169 lockend = offset + count - 1;
6172 ret = btrfs_delalloc_reserve_space(inode, count);
6178 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6179 0, &cached_state, GFP_NOFS);
6181 * We're concerned with the entire range that we're going to be
6182 * doing DIO to, so we need to make sure theres no ordered
6183 * extents in this range.
6185 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6186 lockend - lockstart + 1);
6189 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6190 &cached_state, GFP_NOFS);
6191 btrfs_start_ordered_extent(inode, ordered, 1);
6192 btrfs_put_ordered_extent(ordered);
6197 * we don't use btrfs_set_extent_delalloc because we don't want
6198 * the dirty or uptodate bits
6201 write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING;
6202 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6203 EXTENT_DELALLOC, 0, NULL, &cached_state,
6206 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6207 lockend, EXTENT_LOCKED | write_bits,
6208 1, 0, &cached_state, GFP_NOFS);
6213 free_extent_state(cached_state);
6214 cached_state = NULL;
6216 ret = __blockdev_direct_IO(rw, iocb, inode,
6217 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
6218 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
6219 btrfs_submit_direct, 0);
6221 if (ret < 0 && ret != -EIOCBQUEUED) {
6222 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset,
6223 offset + iov_length(iov, nr_segs) - 1,
6224 EXTENT_LOCKED | write_bits, 1, 0,
6225 &cached_state, GFP_NOFS);
6226 } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) {
6228 * We're falling back to buffered, unlock the section we didn't
6231 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret,
6232 offset + iov_length(iov, nr_segs) - 1,
6233 EXTENT_LOCKED | write_bits, 1, 0,
6234 &cached_state, GFP_NOFS);
6237 free_extent_state(cached_state);
6241 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
6242 __u64 start, __u64 len)
6244 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
6247 int btrfs_readpage(struct file *file, struct page *page)
6249 struct extent_io_tree *tree;
6250 tree = &BTRFS_I(page->mapping->host)->io_tree;
6251 return extent_read_full_page(tree, page, btrfs_get_extent);
6254 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
6256 struct extent_io_tree *tree;
6259 if (current->flags & PF_MEMALLOC) {
6260 redirty_page_for_writepage(wbc, page);
6264 tree = &BTRFS_I(page->mapping->host)->io_tree;
6265 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
6268 int btrfs_writepages(struct address_space *mapping,
6269 struct writeback_control *wbc)
6271 struct extent_io_tree *tree;
6273 tree = &BTRFS_I(mapping->host)->io_tree;
6274 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
6278 btrfs_readpages(struct file *file, struct address_space *mapping,
6279 struct list_head *pages, unsigned nr_pages)
6281 struct extent_io_tree *tree;
6282 tree = &BTRFS_I(mapping->host)->io_tree;
6283 return extent_readpages(tree, mapping, pages, nr_pages,
6286 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6288 struct extent_io_tree *tree;
6289 struct extent_map_tree *map;
6292 tree = &BTRFS_I(page->mapping->host)->io_tree;
6293 map = &BTRFS_I(page->mapping->host)->extent_tree;
6294 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
6296 ClearPagePrivate(page);
6297 set_page_private(page, 0);
6298 page_cache_release(page);
6303 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6305 if (PageWriteback(page) || PageDirty(page))
6307 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
6310 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
6312 struct extent_io_tree *tree;
6313 struct btrfs_ordered_extent *ordered;
6314 struct extent_state *cached_state = NULL;
6315 u64 page_start = page_offset(page);
6316 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
6320 * we have the page locked, so new writeback can't start,
6321 * and the dirty bit won't be cleared while we are here.
6323 * Wait for IO on this page so that we can safely clear
6324 * the PagePrivate2 bit and do ordered accounting
6326 wait_on_page_writeback(page);
6328 tree = &BTRFS_I(page->mapping->host)->io_tree;
6330 btrfs_releasepage(page, GFP_NOFS);
6333 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6335 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
6339 * IO on this page will never be started, so we need
6340 * to account for any ordered extents now
6342 clear_extent_bit(tree, page_start, page_end,
6343 EXTENT_DIRTY | EXTENT_DELALLOC |
6344 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
6345 &cached_state, GFP_NOFS);
6347 * whoever cleared the private bit is responsible
6348 * for the finish_ordered_io
6350 if (TestClearPagePrivate2(page)) {
6351 btrfs_finish_ordered_io(page->mapping->host,
6352 page_start, page_end);
6354 btrfs_put_ordered_extent(ordered);
6355 cached_state = NULL;
6356 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6359 clear_extent_bit(tree, page_start, page_end,
6360 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
6361 EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS);
6362 __btrfs_releasepage(page, GFP_NOFS);
6364 ClearPageChecked(page);
6365 if (PagePrivate(page)) {
6366 ClearPagePrivate(page);
6367 set_page_private(page, 0);
6368 page_cache_release(page);
6373 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
6374 * called from a page fault handler when a page is first dirtied. Hence we must
6375 * be careful to check for EOF conditions here. We set the page up correctly
6376 * for a written page which means we get ENOSPC checking when writing into
6377 * holes and correct delalloc and unwritten extent mapping on filesystems that
6378 * support these features.
6380 * We are not allowed to take the i_mutex here so we have to play games to
6381 * protect against truncate races as the page could now be beyond EOF. Because
6382 * vmtruncate() writes the inode size before removing pages, once we have the
6383 * page lock we can determine safely if the page is beyond EOF. If it is not
6384 * beyond EOF, then the page is guaranteed safe against truncation until we
6387 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
6389 struct page *page = vmf->page;
6390 struct inode *inode = fdentry(vma->vm_file)->d_inode;
6391 struct btrfs_root *root = BTRFS_I(inode)->root;
6392 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6393 struct btrfs_ordered_extent *ordered;
6394 struct extent_state *cached_state = NULL;
6396 unsigned long zero_start;
6402 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
6406 else /* -ENOSPC, -EIO, etc */
6407 ret = VM_FAULT_SIGBUS;
6411 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
6414 size = i_size_read(inode);
6415 page_start = page_offset(page);
6416 page_end = page_start + PAGE_CACHE_SIZE - 1;
6418 if ((page->mapping != inode->i_mapping) ||
6419 (page_start >= size)) {
6420 /* page got truncated out from underneath us */
6423 wait_on_page_writeback(page);
6425 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
6427 set_page_extent_mapped(page);
6430 * we can't set the delalloc bits if there are pending ordered
6431 * extents. Drop our locks and wait for them to finish
6433 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6435 unlock_extent_cached(io_tree, page_start, page_end,
6436 &cached_state, GFP_NOFS);
6438 btrfs_start_ordered_extent(inode, ordered, 1);
6439 btrfs_put_ordered_extent(ordered);
6444 * XXX - page_mkwrite gets called every time the page is dirtied, even
6445 * if it was already dirty, so for space accounting reasons we need to
6446 * clear any delalloc bits for the range we are fixing to save. There
6447 * is probably a better way to do this, but for now keep consistent with
6448 * prepare_pages in the normal write path.
6450 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
6451 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
6452 0, 0, &cached_state, GFP_NOFS);
6454 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
6457 unlock_extent_cached(io_tree, page_start, page_end,
6458 &cached_state, GFP_NOFS);
6459 ret = VM_FAULT_SIGBUS;
6464 /* page is wholly or partially inside EOF */
6465 if (page_start + PAGE_CACHE_SIZE > size)
6466 zero_start = size & ~PAGE_CACHE_MASK;
6468 zero_start = PAGE_CACHE_SIZE;
6470 if (zero_start != PAGE_CACHE_SIZE) {
6472 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
6473 flush_dcache_page(page);
6476 ClearPageChecked(page);
6477 set_page_dirty(page);
6478 SetPageUptodate(page);
6480 BTRFS_I(inode)->last_trans = root->fs_info->generation;
6481 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
6483 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
6487 return VM_FAULT_LOCKED;
6489 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
6494 static int btrfs_truncate(struct inode *inode)
6496 struct btrfs_root *root = BTRFS_I(inode)->root;
6497 struct btrfs_block_rsv *rsv;
6500 struct btrfs_trans_handle *trans;
6502 u64 mask = root->sectorsize - 1;
6504 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
6508 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
6509 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
6512 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
6513 * 3 things going on here
6515 * 1) We need to reserve space for our orphan item and the space to
6516 * delete our orphan item. Lord knows we don't want to have a dangling
6517 * orphan item because we didn't reserve space to remove it.
6519 * 2) We need to reserve space to update our inode.
6521 * 3) We need to have something to cache all the space that is going to
6522 * be free'd up by the truncate operation, but also have some slack
6523 * space reserved in case it uses space during the truncate (thank you
6524 * very much snapshotting).
6526 * And we need these to all be seperate. The fact is we can use alot of
6527 * space doing the truncate, and we have no earthly idea how much space
6528 * we will use, so we need the truncate reservation to be seperate so it
6529 * doesn't end up using space reserved for updating the inode or
6530 * removing the orphan item. We also need to be able to stop the
6531 * transaction and start a new one, which means we need to be able to
6532 * update the inode several times, and we have no idea of knowing how
6533 * many times that will be, so we can't just reserve 1 item for the
6534 * entirety of the opration, so that has to be done seperately as well.
6535 * Then there is the orphan item, which does indeed need to be held on
6536 * to for the whole operation, and we need nobody to touch this reserved
6537 * space except the orphan code.
6539 * So that leaves us with
6541 * 1) root->orphan_block_rsv - for the orphan deletion.
6542 * 2) rsv - for the truncate reservation, which we will steal from the
6543 * transaction reservation.
6544 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
6545 * updating the inode.
6547 rsv = btrfs_alloc_block_rsv(root);
6550 btrfs_add_durable_block_rsv(root->fs_info, rsv);
6552 trans = btrfs_start_transaction(root, 4);
6553 if (IS_ERR(trans)) {
6554 err = PTR_ERR(trans);
6559 * Reserve space for the truncate process. Truncate should be adding
6560 * space, but if there are snapshots it may end up using space.
6562 ret = btrfs_truncate_reserve_metadata(trans, root, rsv);
6565 ret = btrfs_orphan_add(trans, inode);
6567 btrfs_end_transaction(trans, root);
6571 nr = trans->blocks_used;
6572 btrfs_end_transaction(trans, root);
6573 btrfs_btree_balance_dirty(root, nr);
6576 * Ok so we've already migrated our bytes over for the truncate, so here
6577 * just reserve the one slot we need for updating the inode.
6579 trans = btrfs_start_transaction(root, 1);
6580 if (IS_ERR(trans)) {
6581 err = PTR_ERR(trans);
6584 trans->block_rsv = rsv;
6587 * setattr is responsible for setting the ordered_data_close flag,
6588 * but that is only tested during the last file release. That
6589 * could happen well after the next commit, leaving a great big
6590 * window where new writes may get lost if someone chooses to write
6591 * to this file after truncating to zero
6593 * The inode doesn't have any dirty data here, and so if we commit
6594 * this is a noop. If someone immediately starts writing to the inode
6595 * it is very likely we'll catch some of their writes in this
6596 * transaction, and the commit will find this file on the ordered
6597 * data list with good things to send down.
6599 * This is a best effort solution, there is still a window where
6600 * using truncate to replace the contents of the file will
6601 * end up with a zero length file after a crash.
6603 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
6604 btrfs_add_ordered_operation(trans, root, inode);
6608 trans = btrfs_start_transaction(root, 3);
6609 if (IS_ERR(trans)) {
6610 err = PTR_ERR(trans);
6614 ret = btrfs_truncate_reserve_metadata(trans, root,
6618 trans->block_rsv = rsv;
6621 ret = btrfs_truncate_inode_items(trans, root, inode,
6623 BTRFS_EXTENT_DATA_KEY);
6624 if (ret != -EAGAIN) {
6629 trans->block_rsv = &root->fs_info->trans_block_rsv;
6630 ret = btrfs_update_inode(trans, root, inode);
6636 nr = trans->blocks_used;
6637 btrfs_end_transaction(trans, root);
6639 btrfs_btree_balance_dirty(root, nr);
6642 if (ret == 0 && inode->i_nlink > 0) {
6643 trans->block_rsv = root->orphan_block_rsv;
6644 ret = btrfs_orphan_del(trans, inode);
6647 } else if (ret && inode->i_nlink > 0) {
6649 * Failed to do the truncate, remove us from the in memory
6652 ret = btrfs_orphan_del(NULL, inode);
6655 trans->block_rsv = &root->fs_info->trans_block_rsv;
6656 ret = btrfs_update_inode(trans, root, inode);
6660 nr = trans->blocks_used;
6661 ret = btrfs_end_transaction_throttle(trans, root);
6662 btrfs_btree_balance_dirty(root, nr);
6665 btrfs_free_block_rsv(root, rsv);
6674 * create a new subvolume directory/inode (helper for the ioctl).
6676 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
6677 struct btrfs_root *new_root, u64 new_dirid)
6679 struct inode *inode;
6683 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
6684 new_dirid, S_IFDIR | 0700, &index);
6686 return PTR_ERR(inode);
6687 inode->i_op = &btrfs_dir_inode_operations;
6688 inode->i_fop = &btrfs_dir_file_operations;
6691 btrfs_i_size_write(inode, 0);
6693 err = btrfs_update_inode(trans, new_root, inode);
6700 /* helper function for file defrag and space balancing. This
6701 * forces readahead on a given range of bytes in an inode
6703 unsigned long btrfs_force_ra(struct address_space *mapping,
6704 struct file_ra_state *ra, struct file *file,
6705 pgoff_t offset, pgoff_t last_index)
6707 pgoff_t req_size = last_index - offset + 1;
6709 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
6710 return offset + req_size;
6713 struct inode *btrfs_alloc_inode(struct super_block *sb)
6715 struct btrfs_inode *ei;
6716 struct inode *inode;
6718 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
6723 ei->space_info = NULL;
6727 ei->last_sub_trans = 0;
6728 ei->logged_trans = 0;
6729 ei->delalloc_bytes = 0;
6730 ei->reserved_bytes = 0;
6731 ei->disk_i_size = 0;
6733 ei->index_cnt = (u64)-1;
6734 ei->last_unlink_trans = 0;
6736 atomic_set(&ei->outstanding_extents, 0);
6737 atomic_set(&ei->reserved_extents, 0);
6739 ei->ordered_data_close = 0;
6740 ei->orphan_meta_reserved = 0;
6741 ei->dummy_inode = 0;
6743 ei->force_compress = BTRFS_COMPRESS_NONE;
6745 ei->delayed_node = NULL;
6747 inode = &ei->vfs_inode;
6748 extent_map_tree_init(&ei->extent_tree);
6749 extent_io_tree_init(&ei->io_tree, &inode->i_data);
6750 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
6751 mutex_init(&ei->log_mutex);
6752 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
6753 INIT_LIST_HEAD(&ei->i_orphan);
6754 INIT_LIST_HEAD(&ei->delalloc_inodes);
6755 INIT_LIST_HEAD(&ei->ordered_operations);
6756 RB_CLEAR_NODE(&ei->rb_node);
6761 static void btrfs_i_callback(struct rcu_head *head)
6763 struct inode *inode = container_of(head, struct inode, i_rcu);
6764 INIT_LIST_HEAD(&inode->i_dentry);
6765 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
6768 void btrfs_destroy_inode(struct inode *inode)
6770 struct btrfs_ordered_extent *ordered;
6771 struct btrfs_root *root = BTRFS_I(inode)->root;
6773 WARN_ON(!list_empty(&inode->i_dentry));
6774 WARN_ON(inode->i_data.nrpages);
6775 WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents));
6776 WARN_ON(atomic_read(&BTRFS_I(inode)->reserved_extents));
6779 * This can happen where we create an inode, but somebody else also
6780 * created the same inode and we need to destroy the one we already
6787 * Make sure we're properly removed from the ordered operation
6791 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
6792 spin_lock(&root->fs_info->ordered_extent_lock);
6793 list_del_init(&BTRFS_I(inode)->ordered_operations);
6794 spin_unlock(&root->fs_info->ordered_extent_lock);
6797 spin_lock(&root->orphan_lock);
6798 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
6799 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
6800 (unsigned long long)btrfs_ino(inode));
6801 list_del_init(&BTRFS_I(inode)->i_orphan);
6803 spin_unlock(&root->orphan_lock);
6806 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
6810 printk(KERN_ERR "btrfs found ordered "
6811 "extent %llu %llu on inode cleanup\n",
6812 (unsigned long long)ordered->file_offset,
6813 (unsigned long long)ordered->len);
6814 btrfs_remove_ordered_extent(inode, ordered);
6815 btrfs_put_ordered_extent(ordered);
6816 btrfs_put_ordered_extent(ordered);
6819 inode_tree_del(inode);
6820 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
6822 btrfs_remove_delayed_node(inode);
6823 call_rcu(&inode->i_rcu, btrfs_i_callback);
6826 int btrfs_drop_inode(struct inode *inode)
6828 struct btrfs_root *root = BTRFS_I(inode)->root;
6830 if (btrfs_root_refs(&root->root_item) == 0 &&
6831 !is_free_space_inode(root, inode))
6834 return generic_drop_inode(inode);
6837 static void init_once(void *foo)
6839 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
6841 inode_init_once(&ei->vfs_inode);
6844 void btrfs_destroy_cachep(void)
6846 if (btrfs_inode_cachep)
6847 kmem_cache_destroy(btrfs_inode_cachep);
6848 if (btrfs_trans_handle_cachep)
6849 kmem_cache_destroy(btrfs_trans_handle_cachep);
6850 if (btrfs_transaction_cachep)
6851 kmem_cache_destroy(btrfs_transaction_cachep);
6852 if (btrfs_path_cachep)
6853 kmem_cache_destroy(btrfs_path_cachep);
6854 if (btrfs_free_space_cachep)
6855 kmem_cache_destroy(btrfs_free_space_cachep);
6858 int btrfs_init_cachep(void)
6860 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
6861 sizeof(struct btrfs_inode), 0,
6862 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
6863 if (!btrfs_inode_cachep)
6866 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
6867 sizeof(struct btrfs_trans_handle), 0,
6868 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6869 if (!btrfs_trans_handle_cachep)
6872 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
6873 sizeof(struct btrfs_transaction), 0,
6874 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6875 if (!btrfs_transaction_cachep)
6878 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
6879 sizeof(struct btrfs_path), 0,
6880 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6881 if (!btrfs_path_cachep)
6884 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
6885 sizeof(struct btrfs_free_space), 0,
6886 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6887 if (!btrfs_free_space_cachep)
6892 btrfs_destroy_cachep();
6896 static int btrfs_getattr(struct vfsmount *mnt,
6897 struct dentry *dentry, struct kstat *stat)
6899 struct inode *inode = dentry->d_inode;
6900 generic_fillattr(inode, stat);
6901 stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
6902 stat->blksize = PAGE_CACHE_SIZE;
6903 stat->blocks = (inode_get_bytes(inode) +
6904 BTRFS_I(inode)->delalloc_bytes) >> 9;
6909 * If a file is moved, it will inherit the cow and compression flags of the new
6912 static void fixup_inode_flags(struct inode *dir, struct inode *inode)
6914 struct btrfs_inode *b_dir = BTRFS_I(dir);
6915 struct btrfs_inode *b_inode = BTRFS_I(inode);
6917 if (b_dir->flags & BTRFS_INODE_NODATACOW)
6918 b_inode->flags |= BTRFS_INODE_NODATACOW;
6920 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
6922 if (b_dir->flags & BTRFS_INODE_COMPRESS)
6923 b_inode->flags |= BTRFS_INODE_COMPRESS;
6925 b_inode->flags &= ~BTRFS_INODE_COMPRESS;
6928 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
6929 struct inode *new_dir, struct dentry *new_dentry)
6931 struct btrfs_trans_handle *trans;
6932 struct btrfs_root *root = BTRFS_I(old_dir)->root;
6933 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
6934 struct inode *new_inode = new_dentry->d_inode;
6935 struct inode *old_inode = old_dentry->d_inode;
6936 struct timespec ctime = CURRENT_TIME;
6940 u64 old_ino = btrfs_ino(old_inode);
6942 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
6945 /* we only allow rename subvolume link between subvolumes */
6946 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
6949 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
6950 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
6953 if (S_ISDIR(old_inode->i_mode) && new_inode &&
6954 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
6957 * we're using rename to replace one file with another.
6958 * and the replacement file is large. Start IO on it now so
6959 * we don't add too much work to the end of the transaction
6961 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
6962 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
6963 filemap_flush(old_inode->i_mapping);
6965 /* close the racy window with snapshot create/destroy ioctl */
6966 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
6967 down_read(&root->fs_info->subvol_sem);
6969 * We want to reserve the absolute worst case amount of items. So if
6970 * both inodes are subvols and we need to unlink them then that would
6971 * require 4 item modifications, but if they are both normal inodes it
6972 * would require 5 item modifications, so we'll assume their normal
6973 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
6974 * should cover the worst case number of items we'll modify.
6976 trans = btrfs_start_transaction(root, 20);
6977 if (IS_ERR(trans)) {
6978 ret = PTR_ERR(trans);
6983 btrfs_record_root_in_trans(trans, dest);
6985 ret = btrfs_set_inode_index(new_dir, &index);
6989 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6990 /* force full log commit if subvolume involved. */
6991 root->fs_info->last_trans_log_full_commit = trans->transid;
6993 ret = btrfs_insert_inode_ref(trans, dest,
6994 new_dentry->d_name.name,
6995 new_dentry->d_name.len,
6997 btrfs_ino(new_dir), index);
7001 * this is an ugly little race, but the rename is required
7002 * to make sure that if we crash, the inode is either at the
7003 * old name or the new one. pinning the log transaction lets
7004 * us make sure we don't allow a log commit to come in after
7005 * we unlink the name but before we add the new name back in.
7007 btrfs_pin_log_trans(root);
7010 * make sure the inode gets flushed if it is replacing
7013 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
7014 btrfs_add_ordered_operation(trans, root, old_inode);
7016 old_dir->i_ctime = old_dir->i_mtime = ctime;
7017 new_dir->i_ctime = new_dir->i_mtime = ctime;
7018 old_inode->i_ctime = ctime;
7020 if (old_dentry->d_parent != new_dentry->d_parent)
7021 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
7023 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
7024 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
7025 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
7026 old_dentry->d_name.name,
7027 old_dentry->d_name.len);
7029 ret = __btrfs_unlink_inode(trans, root, old_dir,
7030 old_dentry->d_inode,
7031 old_dentry->d_name.name,
7032 old_dentry->d_name.len);
7034 ret = btrfs_update_inode(trans, root, old_inode);
7039 new_inode->i_ctime = CURRENT_TIME;
7040 if (unlikely(btrfs_ino(new_inode) ==
7041 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
7042 root_objectid = BTRFS_I(new_inode)->location.objectid;
7043 ret = btrfs_unlink_subvol(trans, dest, new_dir,
7045 new_dentry->d_name.name,
7046 new_dentry->d_name.len);
7047 BUG_ON(new_inode->i_nlink == 0);
7049 ret = btrfs_unlink_inode(trans, dest, new_dir,
7050 new_dentry->d_inode,
7051 new_dentry->d_name.name,
7052 new_dentry->d_name.len);
7055 if (new_inode->i_nlink == 0) {
7056 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
7061 fixup_inode_flags(new_dir, old_inode);
7063 ret = btrfs_add_link(trans, new_dir, old_inode,
7064 new_dentry->d_name.name,
7065 new_dentry->d_name.len, 0, index);
7068 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
7069 struct dentry *parent = dget_parent(new_dentry);
7070 btrfs_log_new_name(trans, old_inode, old_dir, parent);
7072 btrfs_end_log_trans(root);
7075 btrfs_end_transaction_throttle(trans, root);
7077 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
7078 up_read(&root->fs_info->subvol_sem);
7084 * some fairly slow code that needs optimization. This walks the list
7085 * of all the inodes with pending delalloc and forces them to disk.
7087 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
7089 struct list_head *head = &root->fs_info->delalloc_inodes;
7090 struct btrfs_inode *binode;
7091 struct inode *inode;
7093 if (root->fs_info->sb->s_flags & MS_RDONLY)
7096 spin_lock(&root->fs_info->delalloc_lock);
7097 while (!list_empty(head)) {
7098 binode = list_entry(head->next, struct btrfs_inode,
7100 inode = igrab(&binode->vfs_inode);
7102 list_del_init(&binode->delalloc_inodes);
7103 spin_unlock(&root->fs_info->delalloc_lock);
7105 filemap_flush(inode->i_mapping);
7107 btrfs_add_delayed_iput(inode);
7112 spin_lock(&root->fs_info->delalloc_lock);
7114 spin_unlock(&root->fs_info->delalloc_lock);
7116 /* the filemap_flush will queue IO into the worker threads, but
7117 * we have to make sure the IO is actually started and that
7118 * ordered extents get created before we return
7120 atomic_inc(&root->fs_info->async_submit_draining);
7121 while (atomic_read(&root->fs_info->nr_async_submits) ||
7122 atomic_read(&root->fs_info->async_delalloc_pages)) {
7123 wait_event(root->fs_info->async_submit_wait,
7124 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
7125 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
7127 atomic_dec(&root->fs_info->async_submit_draining);
7131 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
7132 const char *symname)
7134 struct btrfs_trans_handle *trans;
7135 struct btrfs_root *root = BTRFS_I(dir)->root;
7136 struct btrfs_path *path;
7137 struct btrfs_key key;
7138 struct inode *inode = NULL;
7146 struct btrfs_file_extent_item *ei;
7147 struct extent_buffer *leaf;
7148 unsigned long nr = 0;
7150 name_len = strlen(symname) + 1;
7151 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
7152 return -ENAMETOOLONG;
7155 * 2 items for inode item and ref
7156 * 2 items for dir items
7157 * 1 item for xattr if selinux is on
7159 trans = btrfs_start_transaction(root, 5);
7161 return PTR_ERR(trans);
7163 err = btrfs_find_free_ino(root, &objectid);
7167 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
7168 dentry->d_name.len, btrfs_ino(dir), objectid,
7169 S_IFLNK|S_IRWXUGO, &index);
7170 if (IS_ERR(inode)) {
7171 err = PTR_ERR(inode);
7175 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
7181 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
7185 inode->i_mapping->a_ops = &btrfs_aops;
7186 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7187 inode->i_fop = &btrfs_file_operations;
7188 inode->i_op = &btrfs_file_inode_operations;
7189 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
7194 path = btrfs_alloc_path();
7196 key.objectid = btrfs_ino(inode);
7198 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
7199 datasize = btrfs_file_extent_calc_inline_size(name_len);
7200 err = btrfs_insert_empty_item(trans, root, path, &key,
7204 btrfs_free_path(path);
7207 leaf = path->nodes[0];
7208 ei = btrfs_item_ptr(leaf, path->slots[0],
7209 struct btrfs_file_extent_item);
7210 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
7211 btrfs_set_file_extent_type(leaf, ei,
7212 BTRFS_FILE_EXTENT_INLINE);
7213 btrfs_set_file_extent_encryption(leaf, ei, 0);
7214 btrfs_set_file_extent_compression(leaf, ei, 0);
7215 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
7216 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
7218 ptr = btrfs_file_extent_inline_start(ei);
7219 write_extent_buffer(leaf, symname, ptr, name_len);
7220 btrfs_mark_buffer_dirty(leaf);
7221 btrfs_free_path(path);
7223 inode->i_op = &btrfs_symlink_inode_operations;
7224 inode->i_mapping->a_ops = &btrfs_symlink_aops;
7225 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7226 inode_set_bytes(inode, name_len);
7227 btrfs_i_size_write(inode, name_len - 1);
7228 err = btrfs_update_inode(trans, root, inode);
7233 nr = trans->blocks_used;
7234 btrfs_end_transaction_throttle(trans, root);
7236 inode_dec_link_count(inode);
7239 btrfs_btree_balance_dirty(root, nr);
7243 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
7244 u64 start, u64 num_bytes, u64 min_size,
7245 loff_t actual_len, u64 *alloc_hint,
7246 struct btrfs_trans_handle *trans)
7248 struct btrfs_root *root = BTRFS_I(inode)->root;
7249 struct btrfs_key ins;
7250 u64 cur_offset = start;
7253 bool own_trans = true;
7257 while (num_bytes > 0) {
7259 trans = btrfs_start_transaction(root, 3);
7260 if (IS_ERR(trans)) {
7261 ret = PTR_ERR(trans);
7266 ret = btrfs_reserve_extent(trans, root, num_bytes, min_size,
7267 0, *alloc_hint, (u64)-1, &ins, 1);
7270 btrfs_end_transaction(trans, root);
7274 ret = insert_reserved_file_extent(trans, inode,
7275 cur_offset, ins.objectid,
7276 ins.offset, ins.offset,
7277 ins.offset, 0, 0, 0,
7278 BTRFS_FILE_EXTENT_PREALLOC);
7280 btrfs_drop_extent_cache(inode, cur_offset,
7281 cur_offset + ins.offset -1, 0);
7283 num_bytes -= ins.offset;
7284 cur_offset += ins.offset;
7285 *alloc_hint = ins.objectid + ins.offset;
7287 inode->i_ctime = CURRENT_TIME;
7288 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
7289 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
7290 (actual_len > inode->i_size) &&
7291 (cur_offset > inode->i_size)) {
7292 if (cur_offset > actual_len)
7293 i_size = actual_len;
7295 i_size = cur_offset;
7296 i_size_write(inode, i_size);
7297 btrfs_ordered_update_i_size(inode, i_size, NULL);
7300 ret = btrfs_update_inode(trans, root, inode);
7304 btrfs_end_transaction(trans, root);
7309 int btrfs_prealloc_file_range(struct inode *inode, int mode,
7310 u64 start, u64 num_bytes, u64 min_size,
7311 loff_t actual_len, u64 *alloc_hint)
7313 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7314 min_size, actual_len, alloc_hint,
7318 int btrfs_prealloc_file_range_trans(struct inode *inode,
7319 struct btrfs_trans_handle *trans, int mode,
7320 u64 start, u64 num_bytes, u64 min_size,
7321 loff_t actual_len, u64 *alloc_hint)
7323 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7324 min_size, actual_len, alloc_hint, trans);
7327 static int btrfs_set_page_dirty(struct page *page)
7329 return __set_page_dirty_nobuffers(page);
7332 static int btrfs_permission(struct inode *inode, int mask, unsigned int flags)
7334 struct btrfs_root *root = BTRFS_I(inode)->root;
7336 if (btrfs_root_readonly(root) && (mask & MAY_WRITE))
7338 if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE))
7340 return generic_permission(inode, mask, flags, btrfs_check_acl);
7343 static const struct inode_operations btrfs_dir_inode_operations = {
7344 .getattr = btrfs_getattr,
7345 .lookup = btrfs_lookup,
7346 .create = btrfs_create,
7347 .unlink = btrfs_unlink,
7349 .mkdir = btrfs_mkdir,
7350 .rmdir = btrfs_rmdir,
7351 .rename = btrfs_rename,
7352 .symlink = btrfs_symlink,
7353 .setattr = btrfs_setattr,
7354 .mknod = btrfs_mknod,
7355 .setxattr = btrfs_setxattr,
7356 .getxattr = btrfs_getxattr,
7357 .listxattr = btrfs_listxattr,
7358 .removexattr = btrfs_removexattr,
7359 .permission = btrfs_permission,
7361 static const struct inode_operations btrfs_dir_ro_inode_operations = {
7362 .lookup = btrfs_lookup,
7363 .permission = btrfs_permission,
7366 static const struct file_operations btrfs_dir_file_operations = {
7367 .llseek = generic_file_llseek,
7368 .read = generic_read_dir,
7369 .readdir = btrfs_real_readdir,
7370 .unlocked_ioctl = btrfs_ioctl,
7371 #ifdef CONFIG_COMPAT
7372 .compat_ioctl = btrfs_ioctl,
7374 .release = btrfs_release_file,
7375 .fsync = btrfs_sync_file,
7378 static struct extent_io_ops btrfs_extent_io_ops = {
7379 .fill_delalloc = run_delalloc_range,
7380 .submit_bio_hook = btrfs_submit_bio_hook,
7381 .merge_bio_hook = btrfs_merge_bio_hook,
7382 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
7383 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
7384 .writepage_start_hook = btrfs_writepage_start_hook,
7385 .readpage_io_failed_hook = btrfs_io_failed_hook,
7386 .set_bit_hook = btrfs_set_bit_hook,
7387 .clear_bit_hook = btrfs_clear_bit_hook,
7388 .merge_extent_hook = btrfs_merge_extent_hook,
7389 .split_extent_hook = btrfs_split_extent_hook,
7393 * btrfs doesn't support the bmap operation because swapfiles
7394 * use bmap to make a mapping of extents in the file. They assume
7395 * these extents won't change over the life of the file and they
7396 * use the bmap result to do IO directly to the drive.
7398 * the btrfs bmap call would return logical addresses that aren't
7399 * suitable for IO and they also will change frequently as COW
7400 * operations happen. So, swapfile + btrfs == corruption.
7402 * For now we're avoiding this by dropping bmap.
7404 static const struct address_space_operations btrfs_aops = {
7405 .readpage = btrfs_readpage,
7406 .writepage = btrfs_writepage,
7407 .writepages = btrfs_writepages,
7408 .readpages = btrfs_readpages,
7409 .direct_IO = btrfs_direct_IO,
7410 .invalidatepage = btrfs_invalidatepage,
7411 .releasepage = btrfs_releasepage,
7412 .set_page_dirty = btrfs_set_page_dirty,
7413 .error_remove_page = generic_error_remove_page,
7416 static const struct address_space_operations btrfs_symlink_aops = {
7417 .readpage = btrfs_readpage,
7418 .writepage = btrfs_writepage,
7419 .invalidatepage = btrfs_invalidatepage,
7420 .releasepage = btrfs_releasepage,
7423 static const struct inode_operations btrfs_file_inode_operations = {
7424 .getattr = btrfs_getattr,
7425 .setattr = btrfs_setattr,
7426 .setxattr = btrfs_setxattr,
7427 .getxattr = btrfs_getxattr,
7428 .listxattr = btrfs_listxattr,
7429 .removexattr = btrfs_removexattr,
7430 .permission = btrfs_permission,
7431 .fiemap = btrfs_fiemap,
7433 static const struct inode_operations btrfs_special_inode_operations = {
7434 .getattr = btrfs_getattr,
7435 .setattr = btrfs_setattr,
7436 .permission = btrfs_permission,
7437 .setxattr = btrfs_setxattr,
7438 .getxattr = btrfs_getxattr,
7439 .listxattr = btrfs_listxattr,
7440 .removexattr = btrfs_removexattr,
7442 static const struct inode_operations btrfs_symlink_inode_operations = {
7443 .readlink = generic_readlink,
7444 .follow_link = page_follow_link_light,
7445 .put_link = page_put_link,
7446 .getattr = btrfs_getattr,
7447 .permission = btrfs_permission,
7448 .setxattr = btrfs_setxattr,
7449 .getxattr = btrfs_getxattr,
7450 .listxattr = btrfs_listxattr,
7451 .removexattr = btrfs_removexattr,
7454 const struct dentry_operations btrfs_dentry_operations = {
7455 .d_delete = btrfs_dentry_delete,