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>
42 #include "transaction.h"
43 #include "btrfs_inode.h"
45 #include "print-tree.h"
47 #include "ordered-data.h"
50 #include "compression.h"
53 struct btrfs_iget_args {
55 struct btrfs_root *root;
58 static const struct inode_operations btrfs_dir_inode_operations;
59 static const struct inode_operations btrfs_symlink_inode_operations;
60 static const struct inode_operations btrfs_dir_ro_inode_operations;
61 static const struct inode_operations btrfs_special_inode_operations;
62 static const struct inode_operations btrfs_file_inode_operations;
63 static const struct address_space_operations btrfs_aops;
64 static const struct address_space_operations btrfs_symlink_aops;
65 static const struct file_operations btrfs_dir_file_operations;
66 static struct extent_io_ops btrfs_extent_io_ops;
68 static struct kmem_cache *btrfs_inode_cachep;
69 struct kmem_cache *btrfs_trans_handle_cachep;
70 struct kmem_cache *btrfs_transaction_cachep;
71 struct kmem_cache *btrfs_path_cachep;
74 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
75 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
76 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
77 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
78 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
79 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
80 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
81 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
84 static void btrfs_truncate(struct inode *inode);
85 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
86 static noinline int cow_file_range(struct inode *inode,
87 struct page *locked_page,
88 u64 start, u64 end, int *page_started,
89 unsigned long *nr_written, int unlock);
91 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
92 struct inode *inode, struct inode *dir)
96 err = btrfs_init_acl(trans, inode, dir);
98 err = btrfs_xattr_security_init(trans, inode, dir);
103 * this does all the hard work for inserting an inline extent into
104 * the btree. The caller should have done a btrfs_drop_extents so that
105 * no overlapping inline items exist in the btree
107 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
108 struct btrfs_root *root, struct inode *inode,
109 u64 start, size_t size, size_t compressed_size,
110 struct page **compressed_pages)
112 struct btrfs_key key;
113 struct btrfs_path *path;
114 struct extent_buffer *leaf;
115 struct page *page = NULL;
118 struct btrfs_file_extent_item *ei;
121 size_t cur_size = size;
123 unsigned long offset;
124 int use_compress = 0;
126 if (compressed_size && compressed_pages) {
128 cur_size = compressed_size;
131 path = btrfs_alloc_path();
135 path->leave_spinning = 1;
136 btrfs_set_trans_block_group(trans, inode);
138 key.objectid = inode->i_ino;
140 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
141 datasize = btrfs_file_extent_calc_inline_size(cur_size);
143 inode_add_bytes(inode, size);
144 ret = btrfs_insert_empty_item(trans, root, path, &key,
151 leaf = path->nodes[0];
152 ei = btrfs_item_ptr(leaf, path->slots[0],
153 struct btrfs_file_extent_item);
154 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
155 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
156 btrfs_set_file_extent_encryption(leaf, ei, 0);
157 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
158 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
159 ptr = btrfs_file_extent_inline_start(ei);
164 while (compressed_size > 0) {
165 cpage = compressed_pages[i];
166 cur_size = min_t(unsigned long, compressed_size,
169 kaddr = kmap_atomic(cpage, KM_USER0);
170 write_extent_buffer(leaf, kaddr, ptr, cur_size);
171 kunmap_atomic(kaddr, KM_USER0);
175 compressed_size -= cur_size;
177 btrfs_set_file_extent_compression(leaf, ei,
178 BTRFS_COMPRESS_ZLIB);
180 page = find_get_page(inode->i_mapping,
181 start >> PAGE_CACHE_SHIFT);
182 btrfs_set_file_extent_compression(leaf, ei, 0);
183 kaddr = kmap_atomic(page, KM_USER0);
184 offset = start & (PAGE_CACHE_SIZE - 1);
185 write_extent_buffer(leaf, kaddr + offset, ptr, size);
186 kunmap_atomic(kaddr, KM_USER0);
187 page_cache_release(page);
189 btrfs_mark_buffer_dirty(leaf);
190 btrfs_free_path(path);
193 * we're an inline extent, so nobody can
194 * extend the file past i_size without locking
195 * a page we already have locked.
197 * We must do any isize and inode updates
198 * before we unlock the pages. Otherwise we
199 * could end up racing with unlink.
201 BTRFS_I(inode)->disk_i_size = inode->i_size;
202 btrfs_update_inode(trans, root, inode);
206 btrfs_free_path(path);
212 * conditionally insert an inline extent into the file. This
213 * does the checks required to make sure the data is small enough
214 * to fit as an inline extent.
216 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
217 struct btrfs_root *root,
218 struct inode *inode, u64 start, u64 end,
219 size_t compressed_size,
220 struct page **compressed_pages)
222 u64 isize = i_size_read(inode);
223 u64 actual_end = min(end + 1, isize);
224 u64 inline_len = actual_end - start;
225 u64 aligned_end = (end + root->sectorsize - 1) &
226 ~((u64)root->sectorsize - 1);
228 u64 data_len = inline_len;
232 data_len = compressed_size;
235 actual_end >= PAGE_CACHE_SIZE ||
236 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
238 (actual_end & (root->sectorsize - 1)) == 0) ||
240 data_len > root->fs_info->max_inline) {
244 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
248 if (isize > actual_end)
249 inline_len = min_t(u64, isize, actual_end);
250 ret = insert_inline_extent(trans, root, inode, start,
251 inline_len, compressed_size,
254 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
258 struct async_extent {
263 unsigned long nr_pages;
264 struct list_head list;
269 struct btrfs_root *root;
270 struct page *locked_page;
273 struct list_head extents;
274 struct btrfs_work work;
277 static noinline int add_async_extent(struct async_cow *cow,
278 u64 start, u64 ram_size,
281 unsigned long nr_pages)
283 struct async_extent *async_extent;
285 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
286 async_extent->start = start;
287 async_extent->ram_size = ram_size;
288 async_extent->compressed_size = compressed_size;
289 async_extent->pages = pages;
290 async_extent->nr_pages = nr_pages;
291 list_add_tail(&async_extent->list, &cow->extents);
296 * we create compressed extents in two phases. The first
297 * phase compresses a range of pages that have already been
298 * locked (both pages and state bits are locked).
300 * This is done inside an ordered work queue, and the compression
301 * is spread across many cpus. The actual IO submission is step
302 * two, and the ordered work queue takes care of making sure that
303 * happens in the same order things were put onto the queue by
304 * writepages and friends.
306 * If this code finds it can't get good compression, it puts an
307 * entry onto the work queue to write the uncompressed bytes. This
308 * makes sure that both compressed inodes and uncompressed inodes
309 * are written in the same order that pdflush sent them down.
311 static noinline int compress_file_range(struct inode *inode,
312 struct page *locked_page,
314 struct async_cow *async_cow,
317 struct btrfs_root *root = BTRFS_I(inode)->root;
318 struct btrfs_trans_handle *trans;
322 u64 blocksize = root->sectorsize;
324 u64 isize = i_size_read(inode);
326 struct page **pages = NULL;
327 unsigned long nr_pages;
328 unsigned long nr_pages_ret = 0;
329 unsigned long total_compressed = 0;
330 unsigned long total_in = 0;
331 unsigned long max_compressed = 128 * 1024;
332 unsigned long max_uncompressed = 128 * 1024;
338 actual_end = min_t(u64, isize, end + 1);
341 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
342 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
345 * we don't want to send crud past the end of i_size through
346 * compression, that's just a waste of CPU time. So, if the
347 * end of the file is before the start of our current
348 * requested range of bytes, we bail out to the uncompressed
349 * cleanup code that can deal with all of this.
351 * It isn't really the fastest way to fix things, but this is a
352 * very uncommon corner.
354 if (actual_end <= start)
355 goto cleanup_and_bail_uncompressed;
357 total_compressed = actual_end - start;
359 /* we want to make sure that amount of ram required to uncompress
360 * an extent is reasonable, so we limit the total size in ram
361 * of a compressed extent to 128k. This is a crucial number
362 * because it also controls how easily we can spread reads across
363 * cpus for decompression.
365 * We also want to make sure the amount of IO required to do
366 * a random read is reasonably small, so we limit the size of
367 * a compressed extent to 128k.
369 total_compressed = min(total_compressed, max_uncompressed);
370 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
371 num_bytes = max(blocksize, num_bytes);
372 disk_num_bytes = num_bytes;
377 * we do compression for mount -o compress and when the
378 * inode has not been flagged as nocompress. This flag can
379 * change at any time if we discover bad compression ratios.
381 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
382 (btrfs_test_opt(root, COMPRESS) ||
383 (BTRFS_I(inode)->force_compress))) {
385 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
387 ret = btrfs_zlib_compress_pages(inode->i_mapping, start,
388 total_compressed, pages,
389 nr_pages, &nr_pages_ret,
395 unsigned long offset = total_compressed &
396 (PAGE_CACHE_SIZE - 1);
397 struct page *page = pages[nr_pages_ret - 1];
400 /* zero the tail end of the last page, we might be
401 * sending it down to disk
404 kaddr = kmap_atomic(page, KM_USER0);
405 memset(kaddr + offset, 0,
406 PAGE_CACHE_SIZE - offset);
407 kunmap_atomic(kaddr, KM_USER0);
413 trans = btrfs_join_transaction(root, 1);
415 btrfs_set_trans_block_group(trans, inode);
417 /* lets try to make an inline extent */
418 if (ret || total_in < (actual_end - start)) {
419 /* we didn't compress the entire range, try
420 * to make an uncompressed inline extent.
422 ret = cow_file_range_inline(trans, root, inode,
423 start, end, 0, NULL);
425 /* try making a compressed inline extent */
426 ret = cow_file_range_inline(trans, root, inode,
428 total_compressed, pages);
432 * inline extent creation worked, we don't need
433 * to create any more async work items. Unlock
434 * and free up our temp pages.
436 extent_clear_unlock_delalloc(inode,
437 &BTRFS_I(inode)->io_tree,
439 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
440 EXTENT_CLEAR_DELALLOC |
441 EXTENT_CLEAR_ACCOUNTING |
442 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
444 btrfs_end_transaction(trans, root);
447 btrfs_end_transaction(trans, root);
452 * we aren't doing an inline extent round the compressed size
453 * up to a block size boundary so the allocator does sane
456 total_compressed = (total_compressed + blocksize - 1) &
460 * one last check to make sure the compression is really a
461 * win, compare the page count read with the blocks on disk
463 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
464 ~(PAGE_CACHE_SIZE - 1);
465 if (total_compressed >= total_in) {
468 disk_num_bytes = total_compressed;
469 num_bytes = total_in;
472 if (!will_compress && pages) {
474 * the compression code ran but failed to make things smaller,
475 * free any pages it allocated and our page pointer array
477 for (i = 0; i < nr_pages_ret; i++) {
478 WARN_ON(pages[i]->mapping);
479 page_cache_release(pages[i]);
483 total_compressed = 0;
486 /* flag the file so we don't compress in the future */
487 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
488 !(BTRFS_I(inode)->force_compress)) {
489 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
495 /* the async work queues will take care of doing actual
496 * allocation on disk for these compressed pages,
497 * and will submit them to the elevator.
499 add_async_extent(async_cow, start, num_bytes,
500 total_compressed, pages, nr_pages_ret);
502 if (start + num_bytes < end && start + num_bytes < actual_end) {
509 cleanup_and_bail_uncompressed:
511 * No compression, but we still need to write the pages in
512 * the file we've been given so far. redirty the locked
513 * page if it corresponds to our extent and set things up
514 * for the async work queue to run cow_file_range to do
515 * the normal delalloc dance
517 if (page_offset(locked_page) >= start &&
518 page_offset(locked_page) <= end) {
519 __set_page_dirty_nobuffers(locked_page);
520 /* unlocked later on in the async handlers */
522 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0);
530 for (i = 0; i < nr_pages_ret; i++) {
531 WARN_ON(pages[i]->mapping);
532 page_cache_release(pages[i]);
540 * phase two of compressed writeback. This is the ordered portion
541 * of the code, which only gets called in the order the work was
542 * queued. We walk all the async extents created by compress_file_range
543 * and send them down to the disk.
545 static noinline int submit_compressed_extents(struct inode *inode,
546 struct async_cow *async_cow)
548 struct async_extent *async_extent;
550 struct btrfs_trans_handle *trans;
551 struct btrfs_key ins;
552 struct extent_map *em;
553 struct btrfs_root *root = BTRFS_I(inode)->root;
554 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
555 struct extent_io_tree *io_tree;
558 if (list_empty(&async_cow->extents))
562 while (!list_empty(&async_cow->extents)) {
563 async_extent = list_entry(async_cow->extents.next,
564 struct async_extent, list);
565 list_del(&async_extent->list);
567 io_tree = &BTRFS_I(inode)->io_tree;
570 /* did the compression code fall back to uncompressed IO? */
571 if (!async_extent->pages) {
572 int page_started = 0;
573 unsigned long nr_written = 0;
575 lock_extent(io_tree, async_extent->start,
576 async_extent->start +
577 async_extent->ram_size - 1, GFP_NOFS);
579 /* allocate blocks */
580 ret = cow_file_range(inode, async_cow->locked_page,
582 async_extent->start +
583 async_extent->ram_size - 1,
584 &page_started, &nr_written, 0);
587 * if page_started, cow_file_range inserted an
588 * inline extent and took care of all the unlocking
589 * and IO for us. Otherwise, we need to submit
590 * all those pages down to the drive.
592 if (!page_started && !ret)
593 extent_write_locked_range(io_tree,
594 inode, async_extent->start,
595 async_extent->start +
596 async_extent->ram_size - 1,
604 lock_extent(io_tree, async_extent->start,
605 async_extent->start + async_extent->ram_size - 1,
608 trans = btrfs_join_transaction(root, 1);
609 ret = btrfs_reserve_extent(trans, root,
610 async_extent->compressed_size,
611 async_extent->compressed_size,
614 btrfs_end_transaction(trans, root);
618 for (i = 0; i < async_extent->nr_pages; i++) {
619 WARN_ON(async_extent->pages[i]->mapping);
620 page_cache_release(async_extent->pages[i]);
622 kfree(async_extent->pages);
623 async_extent->nr_pages = 0;
624 async_extent->pages = NULL;
625 unlock_extent(io_tree, async_extent->start,
626 async_extent->start +
627 async_extent->ram_size - 1, GFP_NOFS);
632 * here we're doing allocation and writeback of the
635 btrfs_drop_extent_cache(inode, async_extent->start,
636 async_extent->start +
637 async_extent->ram_size - 1, 0);
639 em = alloc_extent_map(GFP_NOFS);
640 em->start = async_extent->start;
641 em->len = async_extent->ram_size;
642 em->orig_start = em->start;
644 em->block_start = ins.objectid;
645 em->block_len = ins.offset;
646 em->bdev = root->fs_info->fs_devices->latest_bdev;
647 set_bit(EXTENT_FLAG_PINNED, &em->flags);
648 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
651 write_lock(&em_tree->lock);
652 ret = add_extent_mapping(em_tree, em);
653 write_unlock(&em_tree->lock);
654 if (ret != -EEXIST) {
658 btrfs_drop_extent_cache(inode, async_extent->start,
659 async_extent->start +
660 async_extent->ram_size - 1, 0);
663 ret = btrfs_add_ordered_extent(inode, async_extent->start,
665 async_extent->ram_size,
667 BTRFS_ORDERED_COMPRESSED);
671 * clear dirty, set writeback and unlock the pages.
673 extent_clear_unlock_delalloc(inode,
674 &BTRFS_I(inode)->io_tree,
676 async_extent->start +
677 async_extent->ram_size - 1,
678 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
679 EXTENT_CLEAR_UNLOCK |
680 EXTENT_CLEAR_DELALLOC |
681 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
683 ret = btrfs_submit_compressed_write(inode,
685 async_extent->ram_size,
687 ins.offset, async_extent->pages,
688 async_extent->nr_pages);
691 alloc_hint = ins.objectid + ins.offset;
700 * when extent_io.c finds a delayed allocation range in the file,
701 * the call backs end up in this code. The basic idea is to
702 * allocate extents on disk for the range, and create ordered data structs
703 * in ram to track those extents.
705 * locked_page is the page that writepage had locked already. We use
706 * it to make sure we don't do extra locks or unlocks.
708 * *page_started is set to one if we unlock locked_page and do everything
709 * required to start IO on it. It may be clean and already done with
712 static noinline int cow_file_range(struct inode *inode,
713 struct page *locked_page,
714 u64 start, u64 end, int *page_started,
715 unsigned long *nr_written,
718 struct btrfs_root *root = BTRFS_I(inode)->root;
719 struct btrfs_trans_handle *trans;
722 unsigned long ram_size;
725 u64 blocksize = root->sectorsize;
727 u64 isize = i_size_read(inode);
728 struct btrfs_key ins;
729 struct extent_map *em;
730 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
733 trans = btrfs_join_transaction(root, 1);
735 btrfs_set_trans_block_group(trans, inode);
737 actual_end = min_t(u64, isize, end + 1);
739 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
740 num_bytes = max(blocksize, num_bytes);
741 disk_num_bytes = num_bytes;
745 /* lets try to make an inline extent */
746 ret = cow_file_range_inline(trans, root, inode,
747 start, end, 0, NULL);
749 extent_clear_unlock_delalloc(inode,
750 &BTRFS_I(inode)->io_tree,
752 EXTENT_CLEAR_UNLOCK_PAGE |
753 EXTENT_CLEAR_UNLOCK |
754 EXTENT_CLEAR_DELALLOC |
755 EXTENT_CLEAR_ACCOUNTING |
757 EXTENT_SET_WRITEBACK |
758 EXTENT_END_WRITEBACK);
760 *nr_written = *nr_written +
761 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
768 BUG_ON(disk_num_bytes >
769 btrfs_super_total_bytes(&root->fs_info->super_copy));
772 read_lock(&BTRFS_I(inode)->extent_tree.lock);
773 em = search_extent_mapping(&BTRFS_I(inode)->extent_tree,
777 * if block start isn't an actual block number then find the
778 * first block in this inode and use that as a hint. If that
779 * block is also bogus then just don't worry about it.
781 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
783 em = search_extent_mapping(em_tree, 0, 0);
784 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
785 alloc_hint = em->block_start;
789 alloc_hint = em->block_start;
793 read_unlock(&BTRFS_I(inode)->extent_tree.lock);
794 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
796 while (disk_num_bytes > 0) {
799 cur_alloc_size = min(disk_num_bytes, root->fs_info->max_extent);
800 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
801 root->sectorsize, 0, alloc_hint,
805 em = alloc_extent_map(GFP_NOFS);
807 em->orig_start = em->start;
808 ram_size = ins.offset;
809 em->len = ins.offset;
811 em->block_start = ins.objectid;
812 em->block_len = ins.offset;
813 em->bdev = root->fs_info->fs_devices->latest_bdev;
814 set_bit(EXTENT_FLAG_PINNED, &em->flags);
817 write_lock(&em_tree->lock);
818 ret = add_extent_mapping(em_tree, em);
819 write_unlock(&em_tree->lock);
820 if (ret != -EEXIST) {
824 btrfs_drop_extent_cache(inode, start,
825 start + ram_size - 1, 0);
828 cur_alloc_size = ins.offset;
829 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
830 ram_size, cur_alloc_size, 0);
833 if (root->root_key.objectid ==
834 BTRFS_DATA_RELOC_TREE_OBJECTID) {
835 ret = btrfs_reloc_clone_csums(inode, start,
840 if (disk_num_bytes < cur_alloc_size)
843 /* we're not doing compressed IO, don't unlock the first
844 * page (which the caller expects to stay locked), don't
845 * clear any dirty bits and don't set any writeback bits
847 * Do set the Private2 bit so we know this page was properly
848 * setup for writepage
850 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
851 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
854 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
855 start, start + ram_size - 1,
857 disk_num_bytes -= cur_alloc_size;
858 num_bytes -= cur_alloc_size;
859 alloc_hint = ins.objectid + ins.offset;
860 start += cur_alloc_size;
864 btrfs_end_transaction(trans, root);
870 * work queue call back to started compression on a file and pages
872 static noinline void async_cow_start(struct btrfs_work *work)
874 struct async_cow *async_cow;
876 async_cow = container_of(work, struct async_cow, work);
878 compress_file_range(async_cow->inode, async_cow->locked_page,
879 async_cow->start, async_cow->end, async_cow,
882 async_cow->inode = NULL;
886 * work queue call back to submit previously compressed pages
888 static noinline void async_cow_submit(struct btrfs_work *work)
890 struct async_cow *async_cow;
891 struct btrfs_root *root;
892 unsigned long nr_pages;
894 async_cow = container_of(work, struct async_cow, work);
896 root = async_cow->root;
897 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
900 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
902 if (atomic_read(&root->fs_info->async_delalloc_pages) <
904 waitqueue_active(&root->fs_info->async_submit_wait))
905 wake_up(&root->fs_info->async_submit_wait);
907 if (async_cow->inode)
908 submit_compressed_extents(async_cow->inode, async_cow);
911 static noinline void async_cow_free(struct btrfs_work *work)
913 struct async_cow *async_cow;
914 async_cow = container_of(work, struct async_cow, work);
918 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
919 u64 start, u64 end, int *page_started,
920 unsigned long *nr_written)
922 struct async_cow *async_cow;
923 struct btrfs_root *root = BTRFS_I(inode)->root;
924 unsigned long nr_pages;
926 int limit = 10 * 1024 * 1042;
928 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
929 1, 0, NULL, GFP_NOFS);
930 while (start < end) {
931 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
932 async_cow->inode = inode;
933 async_cow->root = root;
934 async_cow->locked_page = locked_page;
935 async_cow->start = start;
937 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
940 cur_end = min(end, start + 512 * 1024 - 1);
942 async_cow->end = cur_end;
943 INIT_LIST_HEAD(&async_cow->extents);
945 async_cow->work.func = async_cow_start;
946 async_cow->work.ordered_func = async_cow_submit;
947 async_cow->work.ordered_free = async_cow_free;
948 async_cow->work.flags = 0;
950 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
952 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
954 btrfs_queue_worker(&root->fs_info->delalloc_workers,
957 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
958 wait_event(root->fs_info->async_submit_wait,
959 (atomic_read(&root->fs_info->async_delalloc_pages) <
963 while (atomic_read(&root->fs_info->async_submit_draining) &&
964 atomic_read(&root->fs_info->async_delalloc_pages)) {
965 wait_event(root->fs_info->async_submit_wait,
966 (atomic_read(&root->fs_info->async_delalloc_pages) ==
970 *nr_written += nr_pages;
977 static noinline int csum_exist_in_range(struct btrfs_root *root,
978 u64 bytenr, u64 num_bytes)
981 struct btrfs_ordered_sum *sums;
984 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
985 bytenr + num_bytes - 1, &list);
986 if (ret == 0 && list_empty(&list))
989 while (!list_empty(&list)) {
990 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
991 list_del(&sums->list);
998 * when nowcow writeback call back. This checks for snapshots or COW copies
999 * of the extents that exist in the file, and COWs the file as required.
1001 * If no cow copies or snapshots exist, we write directly to the existing
1004 static noinline int run_delalloc_nocow(struct inode *inode,
1005 struct page *locked_page,
1006 u64 start, u64 end, int *page_started, int force,
1007 unsigned long *nr_written)
1009 struct btrfs_root *root = BTRFS_I(inode)->root;
1010 struct btrfs_trans_handle *trans;
1011 struct extent_buffer *leaf;
1012 struct btrfs_path *path;
1013 struct btrfs_file_extent_item *fi;
1014 struct btrfs_key found_key;
1027 path = btrfs_alloc_path();
1029 trans = btrfs_join_transaction(root, 1);
1032 cow_start = (u64)-1;
1035 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
1038 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1039 leaf = path->nodes[0];
1040 btrfs_item_key_to_cpu(leaf, &found_key,
1041 path->slots[0] - 1);
1042 if (found_key.objectid == inode->i_ino &&
1043 found_key.type == BTRFS_EXTENT_DATA_KEY)
1048 leaf = path->nodes[0];
1049 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1050 ret = btrfs_next_leaf(root, path);
1055 leaf = path->nodes[0];
1061 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1063 if (found_key.objectid > inode->i_ino ||
1064 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1065 found_key.offset > end)
1068 if (found_key.offset > cur_offset) {
1069 extent_end = found_key.offset;
1074 fi = btrfs_item_ptr(leaf, path->slots[0],
1075 struct btrfs_file_extent_item);
1076 extent_type = btrfs_file_extent_type(leaf, fi);
1078 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1079 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1080 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1081 extent_offset = btrfs_file_extent_offset(leaf, fi);
1082 extent_end = found_key.offset +
1083 btrfs_file_extent_num_bytes(leaf, fi);
1084 if (extent_end <= start) {
1088 if (disk_bytenr == 0)
1090 if (btrfs_file_extent_compression(leaf, fi) ||
1091 btrfs_file_extent_encryption(leaf, fi) ||
1092 btrfs_file_extent_other_encoding(leaf, fi))
1094 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1096 if (btrfs_extent_readonly(root, disk_bytenr))
1098 if (btrfs_cross_ref_exist(trans, root, inode->i_ino,
1100 extent_offset, disk_bytenr))
1102 disk_bytenr += extent_offset;
1103 disk_bytenr += cur_offset - found_key.offset;
1104 num_bytes = min(end + 1, extent_end) - cur_offset;
1106 * force cow if csum exists in the range.
1107 * this ensure that csum for a given extent are
1108 * either valid or do not exist.
1110 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1113 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1114 extent_end = found_key.offset +
1115 btrfs_file_extent_inline_len(leaf, fi);
1116 extent_end = ALIGN(extent_end, root->sectorsize);
1121 if (extent_end <= start) {
1126 if (cow_start == (u64)-1)
1127 cow_start = cur_offset;
1128 cur_offset = extent_end;
1129 if (cur_offset > end)
1135 btrfs_release_path(root, path);
1136 if (cow_start != (u64)-1) {
1137 ret = cow_file_range(inode, locked_page, cow_start,
1138 found_key.offset - 1, page_started,
1141 cow_start = (u64)-1;
1144 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1145 struct extent_map *em;
1146 struct extent_map_tree *em_tree;
1147 em_tree = &BTRFS_I(inode)->extent_tree;
1148 em = alloc_extent_map(GFP_NOFS);
1149 em->start = cur_offset;
1150 em->orig_start = em->start;
1151 em->len = num_bytes;
1152 em->block_len = num_bytes;
1153 em->block_start = disk_bytenr;
1154 em->bdev = root->fs_info->fs_devices->latest_bdev;
1155 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1157 write_lock(&em_tree->lock);
1158 ret = add_extent_mapping(em_tree, em);
1159 write_unlock(&em_tree->lock);
1160 if (ret != -EEXIST) {
1161 free_extent_map(em);
1164 btrfs_drop_extent_cache(inode, em->start,
1165 em->start + em->len - 1, 0);
1167 type = BTRFS_ORDERED_PREALLOC;
1169 type = BTRFS_ORDERED_NOCOW;
1172 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1173 num_bytes, num_bytes, type);
1176 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1177 cur_offset, cur_offset + num_bytes - 1,
1178 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1179 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1180 EXTENT_SET_PRIVATE2);
1181 cur_offset = extent_end;
1182 if (cur_offset > end)
1185 btrfs_release_path(root, path);
1187 if (cur_offset <= end && cow_start == (u64)-1)
1188 cow_start = cur_offset;
1189 if (cow_start != (u64)-1) {
1190 ret = cow_file_range(inode, locked_page, cow_start, end,
1191 page_started, nr_written, 1);
1195 ret = btrfs_end_transaction(trans, root);
1197 btrfs_free_path(path);
1202 * extent_io.c call back to do delayed allocation processing
1204 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1205 u64 start, u64 end, int *page_started,
1206 unsigned long *nr_written)
1209 struct btrfs_root *root = BTRFS_I(inode)->root;
1211 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1212 ret = run_delalloc_nocow(inode, locked_page, start, end,
1213 page_started, 1, nr_written);
1214 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1215 ret = run_delalloc_nocow(inode, locked_page, start, end,
1216 page_started, 0, nr_written);
1217 else if (!btrfs_test_opt(root, COMPRESS) &&
1218 !(BTRFS_I(inode)->force_compress))
1219 ret = cow_file_range(inode, locked_page, start, end,
1220 page_started, nr_written, 1);
1222 ret = cow_file_range_async(inode, locked_page, start, end,
1223 page_started, nr_written);
1227 static int btrfs_split_extent_hook(struct inode *inode,
1228 struct extent_state *orig, u64 split)
1230 struct btrfs_root *root = BTRFS_I(inode)->root;
1233 if (!(orig->state & EXTENT_DELALLOC))
1236 size = orig->end - orig->start + 1;
1237 if (size > root->fs_info->max_extent) {
1241 new_size = orig->end - split + 1;
1242 num_extents = div64_u64(size + root->fs_info->max_extent - 1,
1243 root->fs_info->max_extent);
1246 * if we break a large extent up then leave oustanding_extents
1247 * be, since we've already accounted for the large extent.
1249 if (div64_u64(new_size + root->fs_info->max_extent - 1,
1250 root->fs_info->max_extent) < num_extents)
1254 spin_lock(&BTRFS_I(inode)->accounting_lock);
1255 BTRFS_I(inode)->outstanding_extents++;
1256 spin_unlock(&BTRFS_I(inode)->accounting_lock);
1262 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1263 * extents so we can keep track of new extents that are just merged onto old
1264 * extents, such as when we are doing sequential writes, so we can properly
1265 * account for the metadata space we'll need.
1267 static int btrfs_merge_extent_hook(struct inode *inode,
1268 struct extent_state *new,
1269 struct extent_state *other)
1271 struct btrfs_root *root = BTRFS_I(inode)->root;
1272 u64 new_size, old_size;
1275 /* not delalloc, ignore it */
1276 if (!(other->state & EXTENT_DELALLOC))
1279 old_size = other->end - other->start + 1;
1280 if (new->start < other->start)
1281 new_size = other->end - new->start + 1;
1283 new_size = new->end - other->start + 1;
1285 /* we're not bigger than the max, unreserve the space and go */
1286 if (new_size <= root->fs_info->max_extent) {
1287 spin_lock(&BTRFS_I(inode)->accounting_lock);
1288 BTRFS_I(inode)->outstanding_extents--;
1289 spin_unlock(&BTRFS_I(inode)->accounting_lock);
1294 * If we grew by another max_extent, just return, we want to keep that
1297 num_extents = div64_u64(old_size + root->fs_info->max_extent - 1,
1298 root->fs_info->max_extent);
1299 if (div64_u64(new_size + root->fs_info->max_extent - 1,
1300 root->fs_info->max_extent) > num_extents)
1303 spin_lock(&BTRFS_I(inode)->accounting_lock);
1304 BTRFS_I(inode)->outstanding_extents--;
1305 spin_unlock(&BTRFS_I(inode)->accounting_lock);
1311 * extent_io.c set_bit_hook, used to track delayed allocation
1312 * bytes in this file, and to maintain the list of inodes that
1313 * have pending delalloc work to be done.
1315 static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
1316 unsigned long old, unsigned long bits)
1320 * set_bit and clear bit hooks normally require _irqsave/restore
1321 * but in this case, we are only testeing for the DELALLOC
1322 * bit, which is only set or cleared with irqs on
1324 if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
1325 struct btrfs_root *root = BTRFS_I(inode)->root;
1327 spin_lock(&BTRFS_I(inode)->accounting_lock);
1328 BTRFS_I(inode)->outstanding_extents++;
1329 spin_unlock(&BTRFS_I(inode)->accounting_lock);
1330 btrfs_delalloc_reserve_space(root, inode, end - start + 1);
1331 spin_lock(&root->fs_info->delalloc_lock);
1332 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
1333 root->fs_info->delalloc_bytes += end - start + 1;
1334 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1335 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1336 &root->fs_info->delalloc_inodes);
1338 spin_unlock(&root->fs_info->delalloc_lock);
1344 * extent_io.c clear_bit_hook, see set_bit_hook for why
1346 static int btrfs_clear_bit_hook(struct inode *inode,
1347 struct extent_state *state, unsigned long bits)
1350 * set_bit and clear bit hooks normally require _irqsave/restore
1351 * but in this case, we are only testeing for the DELALLOC
1352 * bit, which is only set or cleared with irqs on
1354 if ((state->state & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
1355 struct btrfs_root *root = BTRFS_I(inode)->root;
1357 if (bits & EXTENT_DO_ACCOUNTING) {
1358 spin_lock(&BTRFS_I(inode)->accounting_lock);
1359 BTRFS_I(inode)->outstanding_extents--;
1360 spin_unlock(&BTRFS_I(inode)->accounting_lock);
1361 btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
1364 spin_lock(&root->fs_info->delalloc_lock);
1365 if (state->end - state->start + 1 >
1366 root->fs_info->delalloc_bytes) {
1367 printk(KERN_INFO "btrfs warning: delalloc account "
1369 (unsigned long long)
1370 state->end - state->start + 1,
1371 (unsigned long long)
1372 root->fs_info->delalloc_bytes);
1373 btrfs_delalloc_free_space(root, inode, (u64)-1);
1374 root->fs_info->delalloc_bytes = 0;
1375 BTRFS_I(inode)->delalloc_bytes = 0;
1377 btrfs_delalloc_free_space(root, inode,
1380 root->fs_info->delalloc_bytes -= state->end -
1382 BTRFS_I(inode)->delalloc_bytes -= state->end -
1385 if (BTRFS_I(inode)->delalloc_bytes == 0 &&
1386 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1387 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1389 spin_unlock(&root->fs_info->delalloc_lock);
1395 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1396 * we don't create bios that span stripes or chunks
1398 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1399 size_t size, struct bio *bio,
1400 unsigned long bio_flags)
1402 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1403 struct btrfs_mapping_tree *map_tree;
1404 u64 logical = (u64)bio->bi_sector << 9;
1409 if (bio_flags & EXTENT_BIO_COMPRESSED)
1412 length = bio->bi_size;
1413 map_tree = &root->fs_info->mapping_tree;
1414 map_length = length;
1415 ret = btrfs_map_block(map_tree, READ, logical,
1416 &map_length, NULL, 0);
1418 if (map_length < length + size)
1424 * in order to insert checksums into the metadata in large chunks,
1425 * we wait until bio submission time. All the pages in the bio are
1426 * checksummed and sums are attached onto the ordered extent record.
1428 * At IO completion time the cums attached on the ordered extent record
1429 * are inserted into the btree
1431 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1432 struct bio *bio, int mirror_num,
1433 unsigned long bio_flags)
1435 struct btrfs_root *root = BTRFS_I(inode)->root;
1438 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1444 * in order to insert checksums into the metadata in large chunks,
1445 * we wait until bio submission time. All the pages in the bio are
1446 * checksummed and sums are attached onto the ordered extent record.
1448 * At IO completion time the cums attached on the ordered extent record
1449 * are inserted into the btree
1451 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1452 int mirror_num, unsigned long bio_flags)
1454 struct btrfs_root *root = BTRFS_I(inode)->root;
1455 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1459 * extent_io.c submission hook. This does the right thing for csum calculation
1460 * on write, or reading the csums from the tree before a read
1462 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1463 int mirror_num, unsigned long bio_flags)
1465 struct btrfs_root *root = BTRFS_I(inode)->root;
1469 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1471 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1474 if (!(rw & (1 << BIO_RW))) {
1475 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1476 return btrfs_submit_compressed_read(inode, bio,
1477 mirror_num, bio_flags);
1478 } else if (!skip_sum)
1479 btrfs_lookup_bio_sums(root, inode, bio, NULL);
1481 } else if (!skip_sum) {
1482 /* csum items have already been cloned */
1483 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1485 /* we're doing a write, do the async checksumming */
1486 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1487 inode, rw, bio, mirror_num,
1488 bio_flags, __btrfs_submit_bio_start,
1489 __btrfs_submit_bio_done);
1493 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1497 * given a list of ordered sums record them in the inode. This happens
1498 * at IO completion time based on sums calculated at bio submission time.
1500 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1501 struct inode *inode, u64 file_offset,
1502 struct list_head *list)
1504 struct btrfs_ordered_sum *sum;
1506 btrfs_set_trans_block_group(trans, inode);
1508 list_for_each_entry(sum, list, list) {
1509 btrfs_csum_file_blocks(trans,
1510 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1515 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
1517 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1519 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1523 /* see btrfs_writepage_start_hook for details on why this is required */
1524 struct btrfs_writepage_fixup {
1526 struct btrfs_work work;
1529 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1531 struct btrfs_writepage_fixup *fixup;
1532 struct btrfs_ordered_extent *ordered;
1534 struct inode *inode;
1538 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1542 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1543 ClearPageChecked(page);
1547 inode = page->mapping->host;
1548 page_start = page_offset(page);
1549 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1551 lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
1553 /* already ordered? We're done */
1554 if (PagePrivate2(page))
1557 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1559 unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
1560 page_end, GFP_NOFS);
1562 btrfs_start_ordered_extent(inode, ordered, 1);
1566 btrfs_set_extent_delalloc(inode, page_start, page_end);
1567 ClearPageChecked(page);
1569 unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
1572 page_cache_release(page);
1576 * There are a few paths in the higher layers of the kernel that directly
1577 * set the page dirty bit without asking the filesystem if it is a
1578 * good idea. This causes problems because we want to make sure COW
1579 * properly happens and the data=ordered rules are followed.
1581 * In our case any range that doesn't have the ORDERED bit set
1582 * hasn't been properly setup for IO. We kick off an async process
1583 * to fix it up. The async helper will wait for ordered extents, set
1584 * the delalloc bit and make it safe to write the page.
1586 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1588 struct inode *inode = page->mapping->host;
1589 struct btrfs_writepage_fixup *fixup;
1590 struct btrfs_root *root = BTRFS_I(inode)->root;
1592 /* this page is properly in the ordered list */
1593 if (TestClearPagePrivate2(page))
1596 if (PageChecked(page))
1599 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1603 SetPageChecked(page);
1604 page_cache_get(page);
1605 fixup->work.func = btrfs_writepage_fixup_worker;
1607 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1611 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1612 struct inode *inode, u64 file_pos,
1613 u64 disk_bytenr, u64 disk_num_bytes,
1614 u64 num_bytes, u64 ram_bytes,
1615 u8 compression, u8 encryption,
1616 u16 other_encoding, int extent_type)
1618 struct btrfs_root *root = BTRFS_I(inode)->root;
1619 struct btrfs_file_extent_item *fi;
1620 struct btrfs_path *path;
1621 struct extent_buffer *leaf;
1622 struct btrfs_key ins;
1626 path = btrfs_alloc_path();
1629 path->leave_spinning = 1;
1632 * we may be replacing one extent in the tree with another.
1633 * The new extent is pinned in the extent map, and we don't want
1634 * to drop it from the cache until it is completely in the btree.
1636 * So, tell btrfs_drop_extents to leave this extent in the cache.
1637 * the caller is expected to unpin it and allow it to be merged
1640 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1644 ins.objectid = inode->i_ino;
1645 ins.offset = file_pos;
1646 ins.type = BTRFS_EXTENT_DATA_KEY;
1647 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1649 leaf = path->nodes[0];
1650 fi = btrfs_item_ptr(leaf, path->slots[0],
1651 struct btrfs_file_extent_item);
1652 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1653 btrfs_set_file_extent_type(leaf, fi, extent_type);
1654 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1655 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1656 btrfs_set_file_extent_offset(leaf, fi, 0);
1657 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1658 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1659 btrfs_set_file_extent_compression(leaf, fi, compression);
1660 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1661 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1663 btrfs_unlock_up_safe(path, 1);
1664 btrfs_set_lock_blocking(leaf);
1666 btrfs_mark_buffer_dirty(leaf);
1668 inode_add_bytes(inode, num_bytes);
1670 ins.objectid = disk_bytenr;
1671 ins.offset = disk_num_bytes;
1672 ins.type = BTRFS_EXTENT_ITEM_KEY;
1673 ret = btrfs_alloc_reserved_file_extent(trans, root,
1674 root->root_key.objectid,
1675 inode->i_ino, file_pos, &ins);
1677 btrfs_free_path(path);
1683 * helper function for btrfs_finish_ordered_io, this
1684 * just reads in some of the csum leaves to prime them into ram
1685 * before we start the transaction. It limits the amount of btree
1686 * reads required while inside the transaction.
1688 /* as ordered data IO finishes, this gets called so we can finish
1689 * an ordered extent if the range of bytes in the file it covers are
1692 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1694 struct btrfs_root *root = BTRFS_I(inode)->root;
1695 struct btrfs_trans_handle *trans;
1696 struct btrfs_ordered_extent *ordered_extent = NULL;
1697 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1701 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1705 BUG_ON(!ordered_extent);
1707 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1708 BUG_ON(!list_empty(&ordered_extent->list));
1709 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1711 trans = btrfs_join_transaction(root, 1);
1712 ret = btrfs_update_inode(trans, root, inode);
1714 btrfs_end_transaction(trans, root);
1719 lock_extent(io_tree, ordered_extent->file_offset,
1720 ordered_extent->file_offset + ordered_extent->len - 1,
1723 trans = btrfs_join_transaction(root, 1);
1725 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1727 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1729 ret = btrfs_mark_extent_written(trans, inode,
1730 ordered_extent->file_offset,
1731 ordered_extent->file_offset +
1732 ordered_extent->len);
1735 ret = insert_reserved_file_extent(trans, inode,
1736 ordered_extent->file_offset,
1737 ordered_extent->start,
1738 ordered_extent->disk_len,
1739 ordered_extent->len,
1740 ordered_extent->len,
1742 BTRFS_FILE_EXTENT_REG);
1743 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1744 ordered_extent->file_offset,
1745 ordered_extent->len);
1748 unlock_extent(io_tree, ordered_extent->file_offset,
1749 ordered_extent->file_offset + ordered_extent->len - 1,
1751 add_pending_csums(trans, inode, ordered_extent->file_offset,
1752 &ordered_extent->list);
1754 /* this also removes the ordered extent from the tree */
1755 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1756 ret = btrfs_update_inode(trans, root, inode);
1758 btrfs_end_transaction(trans, root);
1761 btrfs_put_ordered_extent(ordered_extent);
1762 /* once for the tree */
1763 btrfs_put_ordered_extent(ordered_extent);
1768 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1769 struct extent_state *state, int uptodate)
1771 ClearPagePrivate2(page);
1772 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1776 * When IO fails, either with EIO or csum verification fails, we
1777 * try other mirrors that might have a good copy of the data. This
1778 * io_failure_record is used to record state as we go through all the
1779 * mirrors. If another mirror has good data, the page is set up to date
1780 * and things continue. If a good mirror can't be found, the original
1781 * bio end_io callback is called to indicate things have failed.
1783 struct io_failure_record {
1788 unsigned long bio_flags;
1792 static int btrfs_io_failed_hook(struct bio *failed_bio,
1793 struct page *page, u64 start, u64 end,
1794 struct extent_state *state)
1796 struct io_failure_record *failrec = NULL;
1798 struct extent_map *em;
1799 struct inode *inode = page->mapping->host;
1800 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1801 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1808 ret = get_state_private(failure_tree, start, &private);
1810 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
1813 failrec->start = start;
1814 failrec->len = end - start + 1;
1815 failrec->last_mirror = 0;
1816 failrec->bio_flags = 0;
1818 read_lock(&em_tree->lock);
1819 em = lookup_extent_mapping(em_tree, start, failrec->len);
1820 if (em->start > start || em->start + em->len < start) {
1821 free_extent_map(em);
1824 read_unlock(&em_tree->lock);
1826 if (!em || IS_ERR(em)) {
1830 logical = start - em->start;
1831 logical = em->block_start + logical;
1832 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
1833 logical = em->block_start;
1834 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
1836 failrec->logical = logical;
1837 free_extent_map(em);
1838 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
1839 EXTENT_DIRTY, GFP_NOFS);
1840 set_state_private(failure_tree, start,
1841 (u64)(unsigned long)failrec);
1843 failrec = (struct io_failure_record *)(unsigned long)private;
1845 num_copies = btrfs_num_copies(
1846 &BTRFS_I(inode)->root->fs_info->mapping_tree,
1847 failrec->logical, failrec->len);
1848 failrec->last_mirror++;
1850 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1851 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1854 if (state && state->start != failrec->start)
1856 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1858 if (!state || failrec->last_mirror > num_copies) {
1859 set_state_private(failure_tree, failrec->start, 0);
1860 clear_extent_bits(failure_tree, failrec->start,
1861 failrec->start + failrec->len - 1,
1862 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1866 bio = bio_alloc(GFP_NOFS, 1);
1867 bio->bi_private = state;
1868 bio->bi_end_io = failed_bio->bi_end_io;
1869 bio->bi_sector = failrec->logical >> 9;
1870 bio->bi_bdev = failed_bio->bi_bdev;
1873 bio_add_page(bio, page, failrec->len, start - page_offset(page));
1874 if (failed_bio->bi_rw & (1 << BIO_RW))
1879 BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
1880 failrec->last_mirror,
1881 failrec->bio_flags);
1886 * each time an IO finishes, we do a fast check in the IO failure tree
1887 * to see if we need to process or clean up an io_failure_record
1889 static int btrfs_clean_io_failures(struct inode *inode, u64 start)
1892 u64 private_failure;
1893 struct io_failure_record *failure;
1897 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1898 (u64)-1, 1, EXTENT_DIRTY)) {
1899 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
1900 start, &private_failure);
1902 failure = (struct io_failure_record *)(unsigned long)
1904 set_state_private(&BTRFS_I(inode)->io_failure_tree,
1906 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
1908 failure->start + failure->len - 1,
1909 EXTENT_DIRTY | EXTENT_LOCKED,
1918 * when reads are done, we need to check csums to verify the data is correct
1919 * if there's a match, we allow the bio to finish. If not, we go through
1920 * the io_failure_record routines to find good copies
1922 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1923 struct extent_state *state)
1925 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1926 struct inode *inode = page->mapping->host;
1927 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1929 u64 private = ~(u32)0;
1931 struct btrfs_root *root = BTRFS_I(inode)->root;
1934 if (PageChecked(page)) {
1935 ClearPageChecked(page);
1939 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1942 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1943 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1944 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1949 if (state && state->start == start) {
1950 private = state->private;
1953 ret = get_state_private(io_tree, start, &private);
1955 kaddr = kmap_atomic(page, KM_USER0);
1959 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
1960 btrfs_csum_final(csum, (char *)&csum);
1961 if (csum != private)
1964 kunmap_atomic(kaddr, KM_USER0);
1966 /* if the io failure tree for this inode is non-empty,
1967 * check to see if we've recovered from a failed IO
1969 btrfs_clean_io_failures(inode, start);
1973 if (printk_ratelimit()) {
1974 printk(KERN_INFO "btrfs csum failed ino %lu off %llu csum %u "
1975 "private %llu\n", page->mapping->host->i_ino,
1976 (unsigned long long)start, csum,
1977 (unsigned long long)private);
1979 memset(kaddr + offset, 1, end - start + 1);
1980 flush_dcache_page(page);
1981 kunmap_atomic(kaddr, KM_USER0);
1987 struct delayed_iput {
1988 struct list_head list;
1989 struct inode *inode;
1992 void btrfs_add_delayed_iput(struct inode *inode)
1994 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1995 struct delayed_iput *delayed;
1997 if (atomic_add_unless(&inode->i_count, -1, 1))
2000 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2001 delayed->inode = inode;
2003 spin_lock(&fs_info->delayed_iput_lock);
2004 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2005 spin_unlock(&fs_info->delayed_iput_lock);
2008 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2011 struct btrfs_fs_info *fs_info = root->fs_info;
2012 struct delayed_iput *delayed;
2015 spin_lock(&fs_info->delayed_iput_lock);
2016 empty = list_empty(&fs_info->delayed_iputs);
2017 spin_unlock(&fs_info->delayed_iput_lock);
2021 down_read(&root->fs_info->cleanup_work_sem);
2022 spin_lock(&fs_info->delayed_iput_lock);
2023 list_splice_init(&fs_info->delayed_iputs, &list);
2024 spin_unlock(&fs_info->delayed_iput_lock);
2026 while (!list_empty(&list)) {
2027 delayed = list_entry(list.next, struct delayed_iput, list);
2028 list_del(&delayed->list);
2029 iput(delayed->inode);
2032 up_read(&root->fs_info->cleanup_work_sem);
2036 * This creates an orphan entry for the given inode in case something goes
2037 * wrong in the middle of an unlink/truncate.
2039 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2041 struct btrfs_root *root = BTRFS_I(inode)->root;
2044 spin_lock(&root->list_lock);
2046 /* already on the orphan list, we're good */
2047 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2048 spin_unlock(&root->list_lock);
2052 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2054 spin_unlock(&root->list_lock);
2057 * insert an orphan item to track this unlinked/truncated file
2059 ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
2065 * We have done the truncate/delete so we can go ahead and remove the orphan
2066 * item for this particular inode.
2068 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2070 struct btrfs_root *root = BTRFS_I(inode)->root;
2073 spin_lock(&root->list_lock);
2075 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2076 spin_unlock(&root->list_lock);
2080 list_del_init(&BTRFS_I(inode)->i_orphan);
2082 spin_unlock(&root->list_lock);
2086 spin_unlock(&root->list_lock);
2088 ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
2094 * this cleans up any orphans that may be left on the list from the last use
2097 void btrfs_orphan_cleanup(struct btrfs_root *root)
2099 struct btrfs_path *path;
2100 struct extent_buffer *leaf;
2101 struct btrfs_item *item;
2102 struct btrfs_key key, found_key;
2103 struct btrfs_trans_handle *trans;
2104 struct inode *inode;
2105 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2107 if (!xchg(&root->clean_orphans, 0))
2110 path = btrfs_alloc_path();
2114 key.objectid = BTRFS_ORPHAN_OBJECTID;
2115 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2116 key.offset = (u64)-1;
2119 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2121 printk(KERN_ERR "Error searching slot for orphan: %d"
2127 * if ret == 0 means we found what we were searching for, which
2128 * is weird, but possible, so only screw with path if we didnt
2129 * find the key and see if we have stuff that matches
2132 if (path->slots[0] == 0)
2137 /* pull out the item */
2138 leaf = path->nodes[0];
2139 item = btrfs_item_nr(leaf, path->slots[0]);
2140 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2142 /* make sure the item matches what we want */
2143 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2145 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2148 /* release the path since we're done with it */
2149 btrfs_release_path(root, path);
2152 * this is where we are basically btrfs_lookup, without the
2153 * crossing root thing. we store the inode number in the
2154 * offset of the orphan item.
2156 found_key.objectid = found_key.offset;
2157 found_key.type = BTRFS_INODE_ITEM_KEY;
2158 found_key.offset = 0;
2159 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2164 * add this inode to the orphan list so btrfs_orphan_del does
2165 * the proper thing when we hit it
2167 spin_lock(&root->list_lock);
2168 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2169 spin_unlock(&root->list_lock);
2172 * if this is a bad inode, means we actually succeeded in
2173 * removing the inode, but not the orphan record, which means
2174 * we need to manually delete the orphan since iput will just
2175 * do a destroy_inode
2177 if (is_bad_inode(inode)) {
2178 trans = btrfs_start_transaction(root, 1);
2179 btrfs_orphan_del(trans, inode);
2180 btrfs_end_transaction(trans, root);
2185 /* if we have links, this was a truncate, lets do that */
2186 if (inode->i_nlink) {
2188 btrfs_truncate(inode);
2193 /* this will do delete_inode and everything for us */
2198 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2200 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2202 btrfs_free_path(path);
2206 * very simple check to peek ahead in the leaf looking for xattrs. If we
2207 * don't find any xattrs, we know there can't be any acls.
2209 * slot is the slot the inode is in, objectid is the objectid of the inode
2211 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2212 int slot, u64 objectid)
2214 u32 nritems = btrfs_header_nritems(leaf);
2215 struct btrfs_key found_key;
2219 while (slot < nritems) {
2220 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2222 /* we found a different objectid, there must not be acls */
2223 if (found_key.objectid != objectid)
2226 /* we found an xattr, assume we've got an acl */
2227 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2231 * we found a key greater than an xattr key, there can't
2232 * be any acls later on
2234 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2241 * it goes inode, inode backrefs, xattrs, extents,
2242 * so if there are a ton of hard links to an inode there can
2243 * be a lot of backrefs. Don't waste time searching too hard,
2244 * this is just an optimization
2249 /* we hit the end of the leaf before we found an xattr or
2250 * something larger than an xattr. We have to assume the inode
2257 * read an inode from the btree into the in-memory inode
2259 static void btrfs_read_locked_inode(struct inode *inode)
2261 struct btrfs_path *path;
2262 struct extent_buffer *leaf;
2263 struct btrfs_inode_item *inode_item;
2264 struct btrfs_timespec *tspec;
2265 struct btrfs_root *root = BTRFS_I(inode)->root;
2266 struct btrfs_key location;
2268 u64 alloc_group_block;
2272 path = btrfs_alloc_path();
2274 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2276 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2280 leaf = path->nodes[0];
2281 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2282 struct btrfs_inode_item);
2284 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2285 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
2286 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2287 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2288 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2290 tspec = btrfs_inode_atime(inode_item);
2291 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2292 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2294 tspec = btrfs_inode_mtime(inode_item);
2295 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2296 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2298 tspec = btrfs_inode_ctime(inode_item);
2299 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2300 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2302 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2303 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2304 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2305 inode->i_generation = BTRFS_I(inode)->generation;
2307 rdev = btrfs_inode_rdev(leaf, inode_item);
2309 BTRFS_I(inode)->index_cnt = (u64)-1;
2310 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2312 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
2315 * try to precache a NULL acl entry for files that don't have
2316 * any xattrs or acls
2318 maybe_acls = acls_after_inode_item(leaf, path->slots[0], inode->i_ino);
2320 cache_no_acl(inode);
2322 BTRFS_I(inode)->block_group = btrfs_find_block_group(root, 0,
2323 alloc_group_block, 0);
2324 btrfs_free_path(path);
2327 switch (inode->i_mode & S_IFMT) {
2329 inode->i_mapping->a_ops = &btrfs_aops;
2330 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2331 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2332 inode->i_fop = &btrfs_file_operations;
2333 inode->i_op = &btrfs_file_inode_operations;
2336 inode->i_fop = &btrfs_dir_file_operations;
2337 if (root == root->fs_info->tree_root)
2338 inode->i_op = &btrfs_dir_ro_inode_operations;
2340 inode->i_op = &btrfs_dir_inode_operations;
2343 inode->i_op = &btrfs_symlink_inode_operations;
2344 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2345 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2348 inode->i_op = &btrfs_special_inode_operations;
2349 init_special_inode(inode, inode->i_mode, rdev);
2353 btrfs_update_iflags(inode);
2357 btrfs_free_path(path);
2358 make_bad_inode(inode);
2362 * given a leaf and an inode, copy the inode fields into the leaf
2364 static void fill_inode_item(struct btrfs_trans_handle *trans,
2365 struct extent_buffer *leaf,
2366 struct btrfs_inode_item *item,
2367 struct inode *inode)
2369 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2370 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2371 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2372 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2373 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2375 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2376 inode->i_atime.tv_sec);
2377 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2378 inode->i_atime.tv_nsec);
2380 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2381 inode->i_mtime.tv_sec);
2382 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2383 inode->i_mtime.tv_nsec);
2385 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2386 inode->i_ctime.tv_sec);
2387 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2388 inode->i_ctime.tv_nsec);
2390 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2391 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2392 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2393 btrfs_set_inode_transid(leaf, item, trans->transid);
2394 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2395 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2396 btrfs_set_inode_block_group(leaf, item, BTRFS_I(inode)->block_group);
2400 * copy everything in the in-memory inode into the btree.
2402 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2403 struct btrfs_root *root, struct inode *inode)
2405 struct btrfs_inode_item *inode_item;
2406 struct btrfs_path *path;
2407 struct extent_buffer *leaf;
2410 path = btrfs_alloc_path();
2412 path->leave_spinning = 1;
2413 ret = btrfs_lookup_inode(trans, root, path,
2414 &BTRFS_I(inode)->location, 1);
2421 btrfs_unlock_up_safe(path, 1);
2422 leaf = path->nodes[0];
2423 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2424 struct btrfs_inode_item);
2426 fill_inode_item(trans, leaf, inode_item, inode);
2427 btrfs_mark_buffer_dirty(leaf);
2428 btrfs_set_inode_last_trans(trans, inode);
2431 btrfs_free_path(path);
2437 * unlink helper that gets used here in inode.c and in the tree logging
2438 * recovery code. It remove a link in a directory with a given name, and
2439 * also drops the back refs in the inode to the directory
2441 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2442 struct btrfs_root *root,
2443 struct inode *dir, struct inode *inode,
2444 const char *name, int name_len)
2446 struct btrfs_path *path;
2448 struct extent_buffer *leaf;
2449 struct btrfs_dir_item *di;
2450 struct btrfs_key key;
2453 path = btrfs_alloc_path();
2459 path->leave_spinning = 1;
2460 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
2461 name, name_len, -1);
2470 leaf = path->nodes[0];
2471 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2472 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2475 btrfs_release_path(root, path);
2477 ret = btrfs_del_inode_ref(trans, root, name, name_len,
2479 dir->i_ino, &index);
2481 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2482 "inode %lu parent %lu\n", name_len, name,
2483 inode->i_ino, dir->i_ino);
2487 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
2488 index, name, name_len, -1);
2497 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2498 btrfs_release_path(root, path);
2500 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2502 BUG_ON(ret != 0 && ret != -ENOENT);
2504 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2508 btrfs_free_path(path);
2512 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2513 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2514 btrfs_update_inode(trans, root, dir);
2515 btrfs_drop_nlink(inode);
2516 ret = btrfs_update_inode(trans, root, inode);
2521 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2523 struct btrfs_root *root;
2524 struct btrfs_trans_handle *trans;
2525 struct inode *inode = dentry->d_inode;
2527 unsigned long nr = 0;
2529 root = BTRFS_I(dir)->root;
2532 * 5 items for unlink inode
2535 ret = btrfs_reserve_metadata_space(root, 6);
2539 trans = btrfs_start_transaction(root, 1);
2540 if (IS_ERR(trans)) {
2541 btrfs_unreserve_metadata_space(root, 6);
2542 return PTR_ERR(trans);
2545 btrfs_set_trans_block_group(trans, dir);
2547 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
2549 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2550 dentry->d_name.name, dentry->d_name.len);
2552 if (inode->i_nlink == 0)
2553 ret = btrfs_orphan_add(trans, inode);
2555 nr = trans->blocks_used;
2557 btrfs_end_transaction_throttle(trans, root);
2558 btrfs_unreserve_metadata_space(root, 6);
2559 btrfs_btree_balance_dirty(root, nr);
2563 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
2564 struct btrfs_root *root,
2565 struct inode *dir, u64 objectid,
2566 const char *name, int name_len)
2568 struct btrfs_path *path;
2569 struct extent_buffer *leaf;
2570 struct btrfs_dir_item *di;
2571 struct btrfs_key key;
2575 path = btrfs_alloc_path();
2579 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
2580 name, name_len, -1);
2581 BUG_ON(!di || IS_ERR(di));
2583 leaf = path->nodes[0];
2584 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2585 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
2586 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2588 btrfs_release_path(root, path);
2590 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
2591 objectid, root->root_key.objectid,
2592 dir->i_ino, &index, name, name_len);
2594 BUG_ON(ret != -ENOENT);
2595 di = btrfs_search_dir_index_item(root, path, dir->i_ino,
2597 BUG_ON(!di || IS_ERR(di));
2599 leaf = path->nodes[0];
2600 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2601 btrfs_release_path(root, path);
2605 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
2606 index, name, name_len, -1);
2607 BUG_ON(!di || IS_ERR(di));
2609 leaf = path->nodes[0];
2610 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2611 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
2612 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2614 btrfs_release_path(root, path);
2616 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2617 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2618 ret = btrfs_update_inode(trans, root, dir);
2620 dir->i_sb->s_dirt = 1;
2622 btrfs_free_path(path);
2626 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
2628 struct inode *inode = dentry->d_inode;
2631 struct btrfs_root *root = BTRFS_I(dir)->root;
2632 struct btrfs_trans_handle *trans;
2633 unsigned long nr = 0;
2635 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
2636 inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
2639 ret = btrfs_reserve_metadata_space(root, 5);
2643 trans = btrfs_start_transaction(root, 1);
2644 if (IS_ERR(trans)) {
2645 btrfs_unreserve_metadata_space(root, 5);
2646 return PTR_ERR(trans);
2649 btrfs_set_trans_block_group(trans, dir);
2651 if (unlikely(inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
2652 err = btrfs_unlink_subvol(trans, root, dir,
2653 BTRFS_I(inode)->location.objectid,
2654 dentry->d_name.name,
2655 dentry->d_name.len);
2659 err = btrfs_orphan_add(trans, inode);
2663 /* now the directory is empty */
2664 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2665 dentry->d_name.name, dentry->d_name.len);
2667 btrfs_i_size_write(inode, 0);
2669 nr = trans->blocks_used;
2670 ret = btrfs_end_transaction_throttle(trans, root);
2671 btrfs_unreserve_metadata_space(root, 5);
2672 btrfs_btree_balance_dirty(root, nr);
2681 * when truncating bytes in a file, it is possible to avoid reading
2682 * the leaves that contain only checksum items. This can be the
2683 * majority of the IO required to delete a large file, but it must
2684 * be done carefully.
2686 * The keys in the level just above the leaves are checked to make sure
2687 * the lowest key in a given leaf is a csum key, and starts at an offset
2688 * after the new size.
2690 * Then the key for the next leaf is checked to make sure it also has
2691 * a checksum item for the same file. If it does, we know our target leaf
2692 * contains only checksum items, and it can be safely freed without reading
2695 * This is just an optimization targeted at large files. It may do
2696 * nothing. It will return 0 unless things went badly.
2698 static noinline int drop_csum_leaves(struct btrfs_trans_handle *trans,
2699 struct btrfs_root *root,
2700 struct btrfs_path *path,
2701 struct inode *inode, u64 new_size)
2703 struct btrfs_key key;
2706 struct btrfs_key found_key;
2707 struct btrfs_key other_key;
2708 struct btrfs_leaf_ref *ref;
2712 path->lowest_level = 1;
2713 key.objectid = inode->i_ino;
2714 key.type = BTRFS_CSUM_ITEM_KEY;
2715 key.offset = new_size;
2717 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2721 if (path->nodes[1] == NULL) {
2726 btrfs_node_key_to_cpu(path->nodes[1], &found_key, path->slots[1]);
2727 nritems = btrfs_header_nritems(path->nodes[1]);
2732 if (path->slots[1] >= nritems)
2735 /* did we find a key greater than anything we want to delete? */
2736 if (found_key.objectid > inode->i_ino ||
2737 (found_key.objectid == inode->i_ino && found_key.type > key.type))
2740 /* we check the next key in the node to make sure the leave contains
2741 * only checksum items. This comparison doesn't work if our
2742 * leaf is the last one in the node
2744 if (path->slots[1] + 1 >= nritems) {
2746 /* search forward from the last key in the node, this
2747 * will bring us into the next node in the tree
2749 btrfs_node_key_to_cpu(path->nodes[1], &found_key, nritems - 1);
2751 /* unlikely, but we inc below, so check to be safe */
2752 if (found_key.offset == (u64)-1)
2755 /* search_forward needs a path with locks held, do the
2756 * search again for the original key. It is possible
2757 * this will race with a balance and return a path that
2758 * we could modify, but this drop is just an optimization
2759 * and is allowed to miss some leaves.
2761 btrfs_release_path(root, path);
2764 /* setup a max key for search_forward */
2765 other_key.offset = (u64)-1;
2766 other_key.type = key.type;
2767 other_key.objectid = key.objectid;
2769 path->keep_locks = 1;
2770 ret = btrfs_search_forward(root, &found_key, &other_key,
2772 path->keep_locks = 0;
2773 if (ret || found_key.objectid != key.objectid ||
2774 found_key.type != key.type) {
2779 key.offset = found_key.offset;
2780 btrfs_release_path(root, path);
2785 /* we know there's one more slot after us in the tree,
2786 * read that key so we can verify it is also a checksum item
2788 btrfs_node_key_to_cpu(path->nodes[1], &other_key, path->slots[1] + 1);
2790 if (found_key.objectid < inode->i_ino)
2793 if (found_key.type != key.type || found_key.offset < new_size)
2797 * if the key for the next leaf isn't a csum key from this objectid,
2798 * we can't be sure there aren't good items inside this leaf.
2801 if (other_key.objectid != inode->i_ino || other_key.type != key.type)
2804 leaf_start = btrfs_node_blockptr(path->nodes[1], path->slots[1]);
2805 leaf_gen = btrfs_node_ptr_generation(path->nodes[1], path->slots[1]);
2807 * it is safe to delete this leaf, it contains only
2808 * csum items from this inode at an offset >= new_size
2810 ret = btrfs_del_leaf(trans, root, path, leaf_start);
2813 if (root->ref_cows && leaf_gen < trans->transid) {
2814 ref = btrfs_alloc_leaf_ref(root, 0);
2816 ref->root_gen = root->root_key.offset;
2817 ref->bytenr = leaf_start;
2819 ref->generation = leaf_gen;
2822 btrfs_sort_leaf_ref(ref);
2824 ret = btrfs_add_leaf_ref(root, ref, 0);
2826 btrfs_free_leaf_ref(root, ref);
2832 btrfs_release_path(root, path);
2834 if (other_key.objectid == inode->i_ino &&
2835 other_key.type == key.type && other_key.offset > key.offset) {
2836 key.offset = other_key.offset;
2842 /* fixup any changes we've made to the path */
2843 path->lowest_level = 0;
2844 path->keep_locks = 0;
2845 btrfs_release_path(root, path);
2852 * this can truncate away extent items, csum items and directory items.
2853 * It starts at a high offset and removes keys until it can't find
2854 * any higher than new_size
2856 * csum items that cross the new i_size are truncated to the new size
2859 * min_type is the minimum key type to truncate down to. If set to 0, this
2860 * will kill all the items on this inode, including the INODE_ITEM_KEY.
2862 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
2863 struct btrfs_root *root,
2864 struct inode *inode,
2865 u64 new_size, u32 min_type)
2867 struct btrfs_path *path;
2868 struct extent_buffer *leaf;
2869 struct btrfs_file_extent_item *fi;
2870 struct btrfs_key key;
2871 struct btrfs_key found_key;
2872 u64 extent_start = 0;
2873 u64 extent_num_bytes = 0;
2874 u64 extent_offset = 0;
2876 u64 mask = root->sectorsize - 1;
2877 u32 found_type = (u8)-1;
2880 int pending_del_nr = 0;
2881 int pending_del_slot = 0;
2882 int extent_type = -1;
2887 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
2890 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
2892 path = btrfs_alloc_path();
2896 key.objectid = inode->i_ino;
2897 key.offset = (u64)-1;
2901 path->leave_spinning = 1;
2902 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2909 /* there are no items in the tree for us to truncate, we're
2912 if (path->slots[0] == 0)
2919 leaf = path->nodes[0];
2920 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2921 found_type = btrfs_key_type(&found_key);
2924 if (found_key.objectid != inode->i_ino)
2927 if (found_type < min_type)
2930 item_end = found_key.offset;
2931 if (found_type == BTRFS_EXTENT_DATA_KEY) {
2932 fi = btrfs_item_ptr(leaf, path->slots[0],
2933 struct btrfs_file_extent_item);
2934 extent_type = btrfs_file_extent_type(leaf, fi);
2935 encoding = btrfs_file_extent_compression(leaf, fi);
2936 encoding |= btrfs_file_extent_encryption(leaf, fi);
2937 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
2939 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
2941 btrfs_file_extent_num_bytes(leaf, fi);
2942 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
2943 item_end += btrfs_file_extent_inline_len(leaf,
2948 if (found_type > min_type) {
2951 if (item_end < new_size)
2953 if (found_key.offset >= new_size)
2959 /* FIXME, shrink the extent if the ref count is only 1 */
2960 if (found_type != BTRFS_EXTENT_DATA_KEY)
2963 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
2965 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
2966 if (!del_item && !encoding) {
2967 u64 orig_num_bytes =
2968 btrfs_file_extent_num_bytes(leaf, fi);
2969 extent_num_bytes = new_size -
2970 found_key.offset + root->sectorsize - 1;
2971 extent_num_bytes = extent_num_bytes &
2972 ~((u64)root->sectorsize - 1);
2973 btrfs_set_file_extent_num_bytes(leaf, fi,
2975 num_dec = (orig_num_bytes -
2977 if (root->ref_cows && extent_start != 0)
2978 inode_sub_bytes(inode, num_dec);
2979 btrfs_mark_buffer_dirty(leaf);
2982 btrfs_file_extent_disk_num_bytes(leaf,
2984 extent_offset = found_key.offset -
2985 btrfs_file_extent_offset(leaf, fi);
2987 /* FIXME blocksize != 4096 */
2988 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
2989 if (extent_start != 0) {
2992 inode_sub_bytes(inode, num_dec);
2995 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
2997 * we can't truncate inline items that have had
3001 btrfs_file_extent_compression(leaf, fi) == 0 &&
3002 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3003 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3004 u32 size = new_size - found_key.offset;
3006 if (root->ref_cows) {
3007 inode_sub_bytes(inode, item_end + 1 -
3011 btrfs_file_extent_calc_inline_size(size);
3012 ret = btrfs_truncate_item(trans, root, path,
3015 } else if (root->ref_cows) {
3016 inode_sub_bytes(inode, item_end + 1 -
3022 if (!pending_del_nr) {
3023 /* no pending yet, add ourselves */
3024 pending_del_slot = path->slots[0];
3026 } else if (pending_del_nr &&
3027 path->slots[0] + 1 == pending_del_slot) {
3028 /* hop on the pending chunk */
3030 pending_del_slot = path->slots[0];
3037 if (found_extent && root->ref_cows) {
3038 btrfs_set_path_blocking(path);
3039 ret = btrfs_free_extent(trans, root, extent_start,
3040 extent_num_bytes, 0,
3041 btrfs_header_owner(leaf),
3042 inode->i_ino, extent_offset);
3046 if (found_type == BTRFS_INODE_ITEM_KEY)
3049 if (path->slots[0] == 0 ||
3050 path->slots[0] != pending_del_slot) {
3051 if (root->ref_cows) {
3055 if (pending_del_nr) {
3056 ret = btrfs_del_items(trans, root, path,
3062 btrfs_release_path(root, path);
3069 if (pending_del_nr) {
3070 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3073 btrfs_free_path(path);
3078 * taken from block_truncate_page, but does cow as it zeros out
3079 * any bytes left in the last page in the file.
3081 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3083 struct inode *inode = mapping->host;
3084 struct btrfs_root *root = BTRFS_I(inode)->root;
3085 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3086 struct btrfs_ordered_extent *ordered;
3088 u32 blocksize = root->sectorsize;
3089 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3090 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3096 if ((offset & (blocksize - 1)) == 0)
3098 ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE);
3102 ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
3108 page = grab_cache_page(mapping, index);
3110 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
3111 btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
3115 page_start = page_offset(page);
3116 page_end = page_start + PAGE_CACHE_SIZE - 1;
3118 if (!PageUptodate(page)) {
3119 ret = btrfs_readpage(NULL, page);
3121 if (page->mapping != mapping) {
3123 page_cache_release(page);
3126 if (!PageUptodate(page)) {
3131 wait_on_page_writeback(page);
3133 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
3134 set_page_extent_mapped(page);
3136 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3138 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3140 page_cache_release(page);
3141 btrfs_start_ordered_extent(inode, ordered, 1);
3142 btrfs_put_ordered_extent(ordered);
3146 clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
3147 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3150 ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
3152 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3157 if (offset != PAGE_CACHE_SIZE) {
3159 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3160 flush_dcache_page(page);
3163 ClearPageChecked(page);
3164 set_page_dirty(page);
3165 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3169 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
3170 btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
3172 page_cache_release(page);
3177 int btrfs_cont_expand(struct inode *inode, loff_t size)
3179 struct btrfs_trans_handle *trans;
3180 struct btrfs_root *root = BTRFS_I(inode)->root;
3181 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3182 struct extent_map *em;
3183 u64 mask = root->sectorsize - 1;
3184 u64 hole_start = (inode->i_size + mask) & ~mask;
3185 u64 block_end = (size + mask) & ~mask;
3191 if (size <= hole_start)
3195 struct btrfs_ordered_extent *ordered;
3196 btrfs_wait_ordered_range(inode, hole_start,
3197 block_end - hole_start);
3198 lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
3199 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3202 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
3203 btrfs_put_ordered_extent(ordered);
3206 cur_offset = hole_start;
3208 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3209 block_end - cur_offset, 0);
3210 BUG_ON(IS_ERR(em) || !em);
3211 last_byte = min(extent_map_end(em), block_end);
3212 last_byte = (last_byte + mask) & ~mask;
3213 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3215 hole_size = last_byte - cur_offset;
3217 err = btrfs_reserve_metadata_space(root, 2);
3221 trans = btrfs_start_transaction(root, 1);
3222 btrfs_set_trans_block_group(trans, inode);
3224 err = btrfs_drop_extents(trans, inode, cur_offset,
3225 cur_offset + hole_size,
3229 err = btrfs_insert_file_extent(trans, root,
3230 inode->i_ino, cur_offset, 0,
3231 0, hole_size, 0, hole_size,
3235 btrfs_drop_extent_cache(inode, hole_start,
3238 btrfs_end_transaction(trans, root);
3239 btrfs_unreserve_metadata_space(root, 2);
3241 free_extent_map(em);
3242 cur_offset = last_byte;
3243 if (cur_offset >= block_end)
3247 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
3251 static int btrfs_setattr_size(struct inode *inode, struct iattr *attr)
3253 struct btrfs_root *root = BTRFS_I(inode)->root;
3254 struct btrfs_trans_handle *trans;
3258 if (attr->ia_size == inode->i_size)
3261 if (attr->ia_size > inode->i_size) {
3262 unsigned long limit;
3263 limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
3264 if (attr->ia_size > inode->i_sb->s_maxbytes)
3266 if (limit != RLIM_INFINITY && attr->ia_size > limit) {
3267 send_sig(SIGXFSZ, current, 0);
3272 ret = btrfs_reserve_metadata_space(root, 1);
3276 trans = btrfs_start_transaction(root, 1);
3277 btrfs_set_trans_block_group(trans, inode);
3279 ret = btrfs_orphan_add(trans, inode);
3282 nr = trans->blocks_used;
3283 btrfs_end_transaction(trans, root);
3284 btrfs_unreserve_metadata_space(root, 1);
3285 btrfs_btree_balance_dirty(root, nr);
3287 if (attr->ia_size > inode->i_size) {
3288 ret = btrfs_cont_expand(inode, attr->ia_size);
3290 btrfs_truncate(inode);
3294 i_size_write(inode, attr->ia_size);
3295 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
3297 trans = btrfs_start_transaction(root, 1);
3298 btrfs_set_trans_block_group(trans, inode);
3300 ret = btrfs_update_inode(trans, root, inode);
3302 if (inode->i_nlink > 0) {
3303 ret = btrfs_orphan_del(trans, inode);
3306 nr = trans->blocks_used;
3307 btrfs_end_transaction(trans, root);
3308 btrfs_btree_balance_dirty(root, nr);
3313 * We're truncating a file that used to have good data down to
3314 * zero. Make sure it gets into the ordered flush list so that
3315 * any new writes get down to disk quickly.
3317 if (attr->ia_size == 0)
3318 BTRFS_I(inode)->ordered_data_close = 1;
3320 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3321 ret = vmtruncate(inode, attr->ia_size);
3327 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3329 struct inode *inode = dentry->d_inode;
3332 err = inode_change_ok(inode, attr);
3336 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3337 err = btrfs_setattr_size(inode, attr);
3341 attr->ia_valid &= ~ATTR_SIZE;
3344 err = inode_setattr(inode, attr);
3346 if (!err && ((attr->ia_valid & ATTR_MODE)))
3347 err = btrfs_acl_chmod(inode);
3351 void btrfs_delete_inode(struct inode *inode)
3353 struct btrfs_trans_handle *trans;
3354 struct btrfs_root *root = BTRFS_I(inode)->root;
3358 truncate_inode_pages(&inode->i_data, 0);
3359 if (is_bad_inode(inode)) {
3360 btrfs_orphan_del(NULL, inode);
3363 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3365 if (root->fs_info->log_root_recovering) {
3366 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3370 if (inode->i_nlink > 0) {
3371 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3375 btrfs_i_size_write(inode, 0);
3378 trans = btrfs_start_transaction(root, 1);
3379 btrfs_set_trans_block_group(trans, inode);
3380 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3385 nr = trans->blocks_used;
3386 btrfs_end_transaction(trans, root);
3388 btrfs_btree_balance_dirty(root, nr);
3392 ret = btrfs_orphan_del(trans, inode);
3396 nr = trans->blocks_used;
3397 btrfs_end_transaction(trans, root);
3398 btrfs_btree_balance_dirty(root, nr);
3405 * this returns the key found in the dir entry in the location pointer.
3406 * If no dir entries were found, location->objectid is 0.
3408 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3409 struct btrfs_key *location)
3411 const char *name = dentry->d_name.name;
3412 int namelen = dentry->d_name.len;
3413 struct btrfs_dir_item *di;
3414 struct btrfs_path *path;
3415 struct btrfs_root *root = BTRFS_I(dir)->root;
3418 path = btrfs_alloc_path();
3421 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
3426 if (!di || IS_ERR(di))
3429 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3431 btrfs_free_path(path);
3434 location->objectid = 0;
3439 * when we hit a tree root in a directory, the btrfs part of the inode
3440 * needs to be changed to reflect the root directory of the tree root. This
3441 * is kind of like crossing a mount point.
3443 static int fixup_tree_root_location(struct btrfs_root *root,
3445 struct dentry *dentry,
3446 struct btrfs_key *location,
3447 struct btrfs_root **sub_root)
3449 struct btrfs_path *path;
3450 struct btrfs_root *new_root;
3451 struct btrfs_root_ref *ref;
3452 struct extent_buffer *leaf;
3456 path = btrfs_alloc_path();
3463 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3464 BTRFS_I(dir)->root->root_key.objectid,
3465 location->objectid);
3472 leaf = path->nodes[0];
3473 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3474 if (btrfs_root_ref_dirid(leaf, ref) != dir->i_ino ||
3475 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3478 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3479 (unsigned long)(ref + 1),
3480 dentry->d_name.len);
3484 btrfs_release_path(root->fs_info->tree_root, path);
3486 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3487 if (IS_ERR(new_root)) {
3488 err = PTR_ERR(new_root);
3492 if (btrfs_root_refs(&new_root->root_item) == 0) {
3497 *sub_root = new_root;
3498 location->objectid = btrfs_root_dirid(&new_root->root_item);
3499 location->type = BTRFS_INODE_ITEM_KEY;
3500 location->offset = 0;
3503 btrfs_free_path(path);
3507 static void inode_tree_add(struct inode *inode)
3509 struct btrfs_root *root = BTRFS_I(inode)->root;
3510 struct btrfs_inode *entry;
3512 struct rb_node *parent;
3514 p = &root->inode_tree.rb_node;
3517 if (hlist_unhashed(&inode->i_hash))
3520 spin_lock(&root->inode_lock);
3523 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3525 if (inode->i_ino < entry->vfs_inode.i_ino)
3526 p = &parent->rb_left;
3527 else if (inode->i_ino > entry->vfs_inode.i_ino)
3528 p = &parent->rb_right;
3530 WARN_ON(!(entry->vfs_inode.i_state &
3531 (I_WILL_FREE | I_FREEING | I_CLEAR)));
3532 rb_erase(parent, &root->inode_tree);
3533 RB_CLEAR_NODE(parent);
3534 spin_unlock(&root->inode_lock);
3538 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3539 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3540 spin_unlock(&root->inode_lock);
3543 static void inode_tree_del(struct inode *inode)
3545 struct btrfs_root *root = BTRFS_I(inode)->root;
3548 spin_lock(&root->inode_lock);
3549 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3550 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3551 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3552 empty = RB_EMPTY_ROOT(&root->inode_tree);
3554 spin_unlock(&root->inode_lock);
3556 if (empty && btrfs_root_refs(&root->root_item) == 0) {
3557 synchronize_srcu(&root->fs_info->subvol_srcu);
3558 spin_lock(&root->inode_lock);
3559 empty = RB_EMPTY_ROOT(&root->inode_tree);
3560 spin_unlock(&root->inode_lock);
3562 btrfs_add_dead_root(root);
3566 int btrfs_invalidate_inodes(struct btrfs_root *root)
3568 struct rb_node *node;
3569 struct rb_node *prev;
3570 struct btrfs_inode *entry;
3571 struct inode *inode;
3574 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3576 spin_lock(&root->inode_lock);
3578 node = root->inode_tree.rb_node;
3582 entry = rb_entry(node, struct btrfs_inode, rb_node);
3584 if (objectid < entry->vfs_inode.i_ino)
3585 node = node->rb_left;
3586 else if (objectid > entry->vfs_inode.i_ino)
3587 node = node->rb_right;
3593 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3594 if (objectid <= entry->vfs_inode.i_ino) {
3598 prev = rb_next(prev);
3602 entry = rb_entry(node, struct btrfs_inode, rb_node);
3603 objectid = entry->vfs_inode.i_ino + 1;
3604 inode = igrab(&entry->vfs_inode);
3606 spin_unlock(&root->inode_lock);
3607 if (atomic_read(&inode->i_count) > 1)
3608 d_prune_aliases(inode);
3610 * btrfs_drop_inode will remove it from
3611 * the inode cache when its usage count
3616 spin_lock(&root->inode_lock);
3620 if (cond_resched_lock(&root->inode_lock))
3623 node = rb_next(node);
3625 spin_unlock(&root->inode_lock);
3629 static noinline void init_btrfs_i(struct inode *inode)
3631 struct btrfs_inode *bi = BTRFS_I(inode);
3636 bi->last_sub_trans = 0;
3637 bi->logged_trans = 0;
3638 bi->delalloc_bytes = 0;
3639 bi->reserved_bytes = 0;
3640 bi->disk_i_size = 0;
3642 bi->index_cnt = (u64)-1;
3643 bi->last_unlink_trans = 0;
3644 bi->ordered_data_close = 0;
3645 bi->force_compress = 0;
3646 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
3647 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
3648 inode->i_mapping, GFP_NOFS);
3649 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
3650 inode->i_mapping, GFP_NOFS);
3651 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
3652 INIT_LIST_HEAD(&BTRFS_I(inode)->ordered_operations);
3653 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3654 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
3655 mutex_init(&BTRFS_I(inode)->log_mutex);
3658 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3660 struct btrfs_iget_args *args = p;
3661 inode->i_ino = args->ino;
3662 init_btrfs_i(inode);
3663 BTRFS_I(inode)->root = args->root;
3664 btrfs_set_inode_space_info(args->root, inode);
3668 static int btrfs_find_actor(struct inode *inode, void *opaque)
3670 struct btrfs_iget_args *args = opaque;
3671 return args->ino == inode->i_ino &&
3672 args->root == BTRFS_I(inode)->root;
3675 static struct inode *btrfs_iget_locked(struct super_block *s,
3677 struct btrfs_root *root)
3679 struct inode *inode;
3680 struct btrfs_iget_args args;
3681 args.ino = objectid;
3684 inode = iget5_locked(s, objectid, btrfs_find_actor,
3685 btrfs_init_locked_inode,
3690 /* Get an inode object given its location and corresponding root.
3691 * Returns in *is_new if the inode was read from disk
3693 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3694 struct btrfs_root *root, int *new)
3696 struct inode *inode;
3698 inode = btrfs_iget_locked(s, location->objectid, root);
3700 return ERR_PTR(-ENOMEM);
3702 if (inode->i_state & I_NEW) {
3703 BTRFS_I(inode)->root = root;
3704 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3705 btrfs_read_locked_inode(inode);
3707 inode_tree_add(inode);
3708 unlock_new_inode(inode);
3716 static struct inode *new_simple_dir(struct super_block *s,
3717 struct btrfs_key *key,
3718 struct btrfs_root *root)
3720 struct inode *inode = new_inode(s);
3723 return ERR_PTR(-ENOMEM);
3725 init_btrfs_i(inode);
3727 BTRFS_I(inode)->root = root;
3728 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3729 BTRFS_I(inode)->dummy_inode = 1;
3731 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
3732 inode->i_op = &simple_dir_inode_operations;
3733 inode->i_fop = &simple_dir_operations;
3734 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
3735 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3740 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3742 struct inode *inode;
3743 struct btrfs_root *root = BTRFS_I(dir)->root;
3744 struct btrfs_root *sub_root = root;
3745 struct btrfs_key location;
3749 dentry->d_op = &btrfs_dentry_operations;
3751 if (dentry->d_name.len > BTRFS_NAME_LEN)
3752 return ERR_PTR(-ENAMETOOLONG);
3754 ret = btrfs_inode_by_name(dir, dentry, &location);
3757 return ERR_PTR(ret);
3759 if (location.objectid == 0)
3762 if (location.type == BTRFS_INODE_ITEM_KEY) {
3763 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
3767 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
3769 index = srcu_read_lock(&root->fs_info->subvol_srcu);
3770 ret = fixup_tree_root_location(root, dir, dentry,
3771 &location, &sub_root);
3774 inode = ERR_PTR(ret);
3776 inode = new_simple_dir(dir->i_sb, &location, sub_root);
3778 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
3780 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
3782 if (root != sub_root) {
3783 down_read(&root->fs_info->cleanup_work_sem);
3784 if (!(inode->i_sb->s_flags & MS_RDONLY))
3785 btrfs_orphan_cleanup(sub_root);
3786 up_read(&root->fs_info->cleanup_work_sem);
3792 static int btrfs_dentry_delete(struct dentry *dentry)
3794 struct btrfs_root *root;
3796 if (!dentry->d_inode && !IS_ROOT(dentry))
3797 dentry = dentry->d_parent;
3799 if (dentry->d_inode) {
3800 root = BTRFS_I(dentry->d_inode)->root;
3801 if (btrfs_root_refs(&root->root_item) == 0)
3807 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
3808 struct nameidata *nd)
3810 struct inode *inode;
3812 inode = btrfs_lookup_dentry(dir, dentry);
3814 return ERR_CAST(inode);
3816 return d_splice_alias(inode, dentry);
3819 static unsigned char btrfs_filetype_table[] = {
3820 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
3823 static int btrfs_real_readdir(struct file *filp, void *dirent,
3826 struct inode *inode = filp->f_dentry->d_inode;
3827 struct btrfs_root *root = BTRFS_I(inode)->root;
3828 struct btrfs_item *item;
3829 struct btrfs_dir_item *di;
3830 struct btrfs_key key;
3831 struct btrfs_key found_key;
3832 struct btrfs_path *path;
3835 struct extent_buffer *leaf;
3838 unsigned char d_type;
3843 int key_type = BTRFS_DIR_INDEX_KEY;
3848 /* FIXME, use a real flag for deciding about the key type */
3849 if (root->fs_info->tree_root == root)
3850 key_type = BTRFS_DIR_ITEM_KEY;
3852 /* special case for "." */
3853 if (filp->f_pos == 0) {
3854 over = filldir(dirent, ".", 1,
3861 /* special case for .., just use the back ref */
3862 if (filp->f_pos == 1) {
3863 u64 pino = parent_ino(filp->f_path.dentry);
3864 over = filldir(dirent, "..", 2,
3870 path = btrfs_alloc_path();
3873 btrfs_set_key_type(&key, key_type);
3874 key.offset = filp->f_pos;
3875 key.objectid = inode->i_ino;
3877 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3883 leaf = path->nodes[0];
3884 nritems = btrfs_header_nritems(leaf);
3885 slot = path->slots[0];
3886 if (advance || slot >= nritems) {
3887 if (slot >= nritems - 1) {
3888 ret = btrfs_next_leaf(root, path);
3891 leaf = path->nodes[0];
3892 nritems = btrfs_header_nritems(leaf);
3893 slot = path->slots[0];
3901 item = btrfs_item_nr(leaf, slot);
3902 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3904 if (found_key.objectid != key.objectid)
3906 if (btrfs_key_type(&found_key) != key_type)
3908 if (found_key.offset < filp->f_pos)
3911 filp->f_pos = found_key.offset;
3913 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
3915 di_total = btrfs_item_size(leaf, item);
3917 while (di_cur < di_total) {
3918 struct btrfs_key location;
3920 name_len = btrfs_dir_name_len(leaf, di);
3921 if (name_len <= sizeof(tmp_name)) {
3922 name_ptr = tmp_name;
3924 name_ptr = kmalloc(name_len, GFP_NOFS);
3930 read_extent_buffer(leaf, name_ptr,
3931 (unsigned long)(di + 1), name_len);
3933 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
3934 btrfs_dir_item_key_to_cpu(leaf, di, &location);
3936 /* is this a reference to our own snapshot? If so
3939 if (location.type == BTRFS_ROOT_ITEM_KEY &&
3940 location.objectid == root->root_key.objectid) {
3944 over = filldir(dirent, name_ptr, name_len,
3945 found_key.offset, location.objectid,
3949 if (name_ptr != tmp_name)
3954 di_len = btrfs_dir_name_len(leaf, di) +
3955 btrfs_dir_data_len(leaf, di) + sizeof(*di);
3957 di = (struct btrfs_dir_item *)((char *)di + di_len);
3961 /* Reached end of directory/root. Bump pos past the last item. */
3962 if (key_type == BTRFS_DIR_INDEX_KEY)
3964 * 32-bit glibc will use getdents64, but then strtol -
3965 * so the last number we can serve is this.
3967 filp->f_pos = 0x7fffffff;
3973 btrfs_free_path(path);
3977 int btrfs_write_inode(struct inode *inode, int wait)
3979 struct btrfs_root *root = BTRFS_I(inode)->root;
3980 struct btrfs_trans_handle *trans;
3983 if (root->fs_info->btree_inode == inode)
3987 trans = btrfs_join_transaction(root, 1);
3988 btrfs_set_trans_block_group(trans, inode);
3989 ret = btrfs_commit_transaction(trans, root);
3995 * This is somewhat expensive, updating the tree every time the
3996 * inode changes. But, it is most likely to find the inode in cache.
3997 * FIXME, needs more benchmarking...there are no reasons other than performance
3998 * to keep or drop this code.
4000 void btrfs_dirty_inode(struct inode *inode)
4002 struct btrfs_root *root = BTRFS_I(inode)->root;
4003 struct btrfs_trans_handle *trans;
4005 trans = btrfs_join_transaction(root, 1);
4006 btrfs_set_trans_block_group(trans, inode);
4007 btrfs_update_inode(trans, root, inode);
4008 btrfs_end_transaction(trans, root);
4012 * find the highest existing sequence number in a directory
4013 * and then set the in-memory index_cnt variable to reflect
4014 * free sequence numbers
4016 static int btrfs_set_inode_index_count(struct inode *inode)
4018 struct btrfs_root *root = BTRFS_I(inode)->root;
4019 struct btrfs_key key, found_key;
4020 struct btrfs_path *path;
4021 struct extent_buffer *leaf;
4024 key.objectid = inode->i_ino;
4025 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4026 key.offset = (u64)-1;
4028 path = btrfs_alloc_path();
4032 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4035 /* FIXME: we should be able to handle this */
4041 * MAGIC NUMBER EXPLANATION:
4042 * since we search a directory based on f_pos we have to start at 2
4043 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4044 * else has to start at 2
4046 if (path->slots[0] == 0) {
4047 BTRFS_I(inode)->index_cnt = 2;
4053 leaf = path->nodes[0];
4054 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4056 if (found_key.objectid != inode->i_ino ||
4057 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4058 BTRFS_I(inode)->index_cnt = 2;
4062 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4064 btrfs_free_path(path);
4069 * helper to find a free sequence number in a given directory. This current
4070 * code is very simple, later versions will do smarter things in the btree
4072 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4076 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4077 ret = btrfs_set_inode_index_count(dir);
4082 *index = BTRFS_I(dir)->index_cnt;
4083 BTRFS_I(dir)->index_cnt++;
4088 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4089 struct btrfs_root *root,
4091 const char *name, int name_len,
4092 u64 ref_objectid, u64 objectid,
4093 u64 alloc_hint, int mode, u64 *index)
4095 struct inode *inode;
4096 struct btrfs_inode_item *inode_item;
4097 struct btrfs_key *location;
4098 struct btrfs_path *path;
4099 struct btrfs_inode_ref *ref;
4100 struct btrfs_key key[2];
4106 path = btrfs_alloc_path();
4109 inode = new_inode(root->fs_info->sb);
4111 return ERR_PTR(-ENOMEM);
4114 ret = btrfs_set_inode_index(dir, index);
4117 return ERR_PTR(ret);
4121 * index_cnt is ignored for everything but a dir,
4122 * btrfs_get_inode_index_count has an explanation for the magic
4125 init_btrfs_i(inode);
4126 BTRFS_I(inode)->index_cnt = 2;
4127 BTRFS_I(inode)->root = root;
4128 BTRFS_I(inode)->generation = trans->transid;
4129 btrfs_set_inode_space_info(root, inode);
4135 BTRFS_I(inode)->block_group =
4136 btrfs_find_block_group(root, 0, alloc_hint, owner);
4138 key[0].objectid = objectid;
4139 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4142 key[1].objectid = objectid;
4143 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4144 key[1].offset = ref_objectid;
4146 sizes[0] = sizeof(struct btrfs_inode_item);
4147 sizes[1] = name_len + sizeof(*ref);
4149 path->leave_spinning = 1;
4150 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4154 inode->i_uid = current_fsuid();
4156 if (dir && (dir->i_mode & S_ISGID)) {
4157 inode->i_gid = dir->i_gid;
4161 inode->i_gid = current_fsgid();
4163 inode->i_mode = mode;
4164 inode->i_ino = objectid;
4165 inode_set_bytes(inode, 0);
4166 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4167 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4168 struct btrfs_inode_item);
4169 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4171 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4172 struct btrfs_inode_ref);
4173 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4174 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4175 ptr = (unsigned long)(ref + 1);
4176 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4178 btrfs_mark_buffer_dirty(path->nodes[0]);
4179 btrfs_free_path(path);
4181 location = &BTRFS_I(inode)->location;
4182 location->objectid = objectid;
4183 location->offset = 0;
4184 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4186 btrfs_inherit_iflags(inode, dir);
4188 if ((mode & S_IFREG)) {
4189 if (btrfs_test_opt(root, NODATASUM))
4190 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4191 if (btrfs_test_opt(root, NODATACOW))
4192 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4195 insert_inode_hash(inode);
4196 inode_tree_add(inode);
4200 BTRFS_I(dir)->index_cnt--;
4201 btrfs_free_path(path);
4203 return ERR_PTR(ret);
4206 static inline u8 btrfs_inode_type(struct inode *inode)
4208 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4212 * utility function to add 'inode' into 'parent_inode' with
4213 * a give name and a given sequence number.
4214 * if 'add_backref' is true, also insert a backref from the
4215 * inode to the parent directory.
4217 int btrfs_add_link(struct btrfs_trans_handle *trans,
4218 struct inode *parent_inode, struct inode *inode,
4219 const char *name, int name_len, int add_backref, u64 index)
4222 struct btrfs_key key;
4223 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4225 if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
4226 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4228 key.objectid = inode->i_ino;
4229 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4233 if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
4234 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4235 key.objectid, root->root_key.objectid,
4236 parent_inode->i_ino,
4237 index, name, name_len);
4238 } else if (add_backref) {
4239 ret = btrfs_insert_inode_ref(trans, root,
4240 name, name_len, inode->i_ino,
4241 parent_inode->i_ino, index);
4245 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4246 parent_inode->i_ino, &key,
4247 btrfs_inode_type(inode), index);
4250 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4252 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4253 ret = btrfs_update_inode(trans, root, parent_inode);
4258 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4259 struct dentry *dentry, struct inode *inode,
4260 int backref, u64 index)
4262 int err = btrfs_add_link(trans, dentry->d_parent->d_inode,
4263 inode, dentry->d_name.name,
4264 dentry->d_name.len, backref, index);
4266 d_instantiate(dentry, inode);
4274 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4275 int mode, dev_t rdev)
4277 struct btrfs_trans_handle *trans;
4278 struct btrfs_root *root = BTRFS_I(dir)->root;
4279 struct inode *inode = NULL;
4283 unsigned long nr = 0;
4286 if (!new_valid_dev(rdev))
4290 * 2 for inode item and ref
4292 * 1 for xattr if selinux is on
4294 err = btrfs_reserve_metadata_space(root, 5);
4298 trans = btrfs_start_transaction(root, 1);
4301 btrfs_set_trans_block_group(trans, dir);
4303 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
4309 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4311 dentry->d_parent->d_inode->i_ino, objectid,
4312 BTRFS_I(dir)->block_group, mode, &index);
4313 err = PTR_ERR(inode);
4317 err = btrfs_init_inode_security(trans, inode, dir);
4323 btrfs_set_trans_block_group(trans, inode);
4324 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
4328 inode->i_op = &btrfs_special_inode_operations;
4329 init_special_inode(inode, inode->i_mode, rdev);
4330 btrfs_update_inode(trans, root, inode);
4332 btrfs_update_inode_block_group(trans, inode);
4333 btrfs_update_inode_block_group(trans, dir);
4335 nr = trans->blocks_used;
4336 btrfs_end_transaction_throttle(trans, root);
4338 btrfs_unreserve_metadata_space(root, 5);
4340 inode_dec_link_count(inode);
4343 btrfs_btree_balance_dirty(root, nr);
4347 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4348 int mode, struct nameidata *nd)
4350 struct btrfs_trans_handle *trans;
4351 struct btrfs_root *root = BTRFS_I(dir)->root;
4352 struct inode *inode = NULL;
4355 unsigned long nr = 0;
4360 * 2 for inode item and ref
4362 * 1 for xattr if selinux is on
4364 err = btrfs_reserve_metadata_space(root, 5);
4368 trans = btrfs_start_transaction(root, 1);
4371 btrfs_set_trans_block_group(trans, dir);
4373 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
4379 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4381 dentry->d_parent->d_inode->i_ino,
4382 objectid, BTRFS_I(dir)->block_group, mode,
4384 err = PTR_ERR(inode);
4388 err = btrfs_init_inode_security(trans, inode, dir);
4394 btrfs_set_trans_block_group(trans, inode);
4395 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
4399 inode->i_mapping->a_ops = &btrfs_aops;
4400 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4401 inode->i_fop = &btrfs_file_operations;
4402 inode->i_op = &btrfs_file_inode_operations;
4403 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4405 btrfs_update_inode_block_group(trans, inode);
4406 btrfs_update_inode_block_group(trans, dir);
4408 nr = trans->blocks_used;
4409 btrfs_end_transaction_throttle(trans, root);
4411 btrfs_unreserve_metadata_space(root, 5);
4413 inode_dec_link_count(inode);
4416 btrfs_btree_balance_dirty(root, nr);
4420 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4421 struct dentry *dentry)
4423 struct btrfs_trans_handle *trans;
4424 struct btrfs_root *root = BTRFS_I(dir)->root;
4425 struct inode *inode = old_dentry->d_inode;
4427 unsigned long nr = 0;
4431 if (inode->i_nlink == 0)
4434 /* do not allow sys_link's with other subvols of the same device */
4435 if (root->objectid != BTRFS_I(inode)->root->objectid)
4439 * 1 item for inode ref
4440 * 2 items for dir items
4442 err = btrfs_reserve_metadata_space(root, 3);
4446 btrfs_inc_nlink(inode);
4448 err = btrfs_set_inode_index(dir, &index);
4452 trans = btrfs_start_transaction(root, 1);
4454 btrfs_set_trans_block_group(trans, dir);
4455 atomic_inc(&inode->i_count);
4457 err = btrfs_add_nondir(trans, dentry, inode, 1, index);
4462 btrfs_update_inode_block_group(trans, dir);
4463 err = btrfs_update_inode(trans, root, inode);
4465 btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
4468 nr = trans->blocks_used;
4469 btrfs_end_transaction_throttle(trans, root);
4471 btrfs_unreserve_metadata_space(root, 3);
4473 inode_dec_link_count(inode);
4476 btrfs_btree_balance_dirty(root, nr);
4480 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4482 struct inode *inode = NULL;
4483 struct btrfs_trans_handle *trans;
4484 struct btrfs_root *root = BTRFS_I(dir)->root;
4486 int drop_on_err = 0;
4489 unsigned long nr = 1;
4492 * 2 items for inode and ref
4493 * 2 items for dir items
4494 * 1 for xattr if selinux is on
4496 err = btrfs_reserve_metadata_space(root, 5);
4500 trans = btrfs_start_transaction(root, 1);
4505 btrfs_set_trans_block_group(trans, dir);
4507 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
4513 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4515 dentry->d_parent->d_inode->i_ino, objectid,
4516 BTRFS_I(dir)->block_group, S_IFDIR | mode,
4518 if (IS_ERR(inode)) {
4519 err = PTR_ERR(inode);
4525 err = btrfs_init_inode_security(trans, inode, dir);
4529 inode->i_op = &btrfs_dir_inode_operations;
4530 inode->i_fop = &btrfs_dir_file_operations;
4531 btrfs_set_trans_block_group(trans, inode);
4533 btrfs_i_size_write(inode, 0);
4534 err = btrfs_update_inode(trans, root, inode);
4538 err = btrfs_add_link(trans, dentry->d_parent->d_inode,
4539 inode, dentry->d_name.name,
4540 dentry->d_name.len, 0, index);
4544 d_instantiate(dentry, inode);
4546 btrfs_update_inode_block_group(trans, inode);
4547 btrfs_update_inode_block_group(trans, dir);
4550 nr = trans->blocks_used;
4551 btrfs_end_transaction_throttle(trans, root);
4554 btrfs_unreserve_metadata_space(root, 5);
4557 btrfs_btree_balance_dirty(root, nr);
4561 /* helper for btfs_get_extent. Given an existing extent in the tree,
4562 * and an extent that you want to insert, deal with overlap and insert
4563 * the new extent into the tree.
4565 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4566 struct extent_map *existing,
4567 struct extent_map *em,
4568 u64 map_start, u64 map_len)
4572 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4573 start_diff = map_start - em->start;
4574 em->start = map_start;
4576 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4577 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4578 em->block_start += start_diff;
4579 em->block_len -= start_diff;
4581 return add_extent_mapping(em_tree, em);
4584 static noinline int uncompress_inline(struct btrfs_path *path,
4585 struct inode *inode, struct page *page,
4586 size_t pg_offset, u64 extent_offset,
4587 struct btrfs_file_extent_item *item)
4590 struct extent_buffer *leaf = path->nodes[0];
4593 unsigned long inline_size;
4596 WARN_ON(pg_offset != 0);
4597 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4598 inline_size = btrfs_file_extent_inline_item_len(leaf,
4599 btrfs_item_nr(leaf, path->slots[0]));
4600 tmp = kmalloc(inline_size, GFP_NOFS);
4601 ptr = btrfs_file_extent_inline_start(item);
4603 read_extent_buffer(leaf, tmp, ptr, inline_size);
4605 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4606 ret = btrfs_zlib_decompress(tmp, page, extent_offset,
4607 inline_size, max_size);
4609 char *kaddr = kmap_atomic(page, KM_USER0);
4610 unsigned long copy_size = min_t(u64,
4611 PAGE_CACHE_SIZE - pg_offset,
4612 max_size - extent_offset);
4613 memset(kaddr + pg_offset, 0, copy_size);
4614 kunmap_atomic(kaddr, KM_USER0);
4621 * a bit scary, this does extent mapping from logical file offset to the disk.
4622 * the ugly parts come from merging extents from the disk with the in-ram
4623 * representation. This gets more complex because of the data=ordered code,
4624 * where the in-ram extents might be locked pending data=ordered completion.
4626 * This also copies inline extents directly into the page.
4629 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4630 size_t pg_offset, u64 start, u64 len,
4636 u64 extent_start = 0;
4638 u64 objectid = inode->i_ino;
4640 struct btrfs_path *path = NULL;
4641 struct btrfs_root *root = BTRFS_I(inode)->root;
4642 struct btrfs_file_extent_item *item;
4643 struct extent_buffer *leaf;
4644 struct btrfs_key found_key;
4645 struct extent_map *em = NULL;
4646 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4647 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4648 struct btrfs_trans_handle *trans = NULL;
4652 read_lock(&em_tree->lock);
4653 em = lookup_extent_mapping(em_tree, start, len);
4655 em->bdev = root->fs_info->fs_devices->latest_bdev;
4656 read_unlock(&em_tree->lock);
4659 if (em->start > start || em->start + em->len <= start)
4660 free_extent_map(em);
4661 else if (em->block_start == EXTENT_MAP_INLINE && page)
4662 free_extent_map(em);
4666 em = alloc_extent_map(GFP_NOFS);
4671 em->bdev = root->fs_info->fs_devices->latest_bdev;
4672 em->start = EXTENT_MAP_HOLE;
4673 em->orig_start = EXTENT_MAP_HOLE;
4675 em->block_len = (u64)-1;
4678 path = btrfs_alloc_path();
4682 ret = btrfs_lookup_file_extent(trans, root, path,
4683 objectid, start, trans != NULL);
4690 if (path->slots[0] == 0)
4695 leaf = path->nodes[0];
4696 item = btrfs_item_ptr(leaf, path->slots[0],
4697 struct btrfs_file_extent_item);
4698 /* are we inside the extent that was found? */
4699 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4700 found_type = btrfs_key_type(&found_key);
4701 if (found_key.objectid != objectid ||
4702 found_type != BTRFS_EXTENT_DATA_KEY) {
4706 found_type = btrfs_file_extent_type(leaf, item);
4707 extent_start = found_key.offset;
4708 compressed = btrfs_file_extent_compression(leaf, item);
4709 if (found_type == BTRFS_FILE_EXTENT_REG ||
4710 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
4711 extent_end = extent_start +
4712 btrfs_file_extent_num_bytes(leaf, item);
4713 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
4715 size = btrfs_file_extent_inline_len(leaf, item);
4716 extent_end = (extent_start + size + root->sectorsize - 1) &
4717 ~((u64)root->sectorsize - 1);
4720 if (start >= extent_end) {
4722 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
4723 ret = btrfs_next_leaf(root, path);
4730 leaf = path->nodes[0];
4732 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4733 if (found_key.objectid != objectid ||
4734 found_key.type != BTRFS_EXTENT_DATA_KEY)
4736 if (start + len <= found_key.offset)
4739 em->len = found_key.offset - start;
4743 if (found_type == BTRFS_FILE_EXTENT_REG ||
4744 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
4745 em->start = extent_start;
4746 em->len = extent_end - extent_start;
4747 em->orig_start = extent_start -
4748 btrfs_file_extent_offset(leaf, item);
4749 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
4751 em->block_start = EXTENT_MAP_HOLE;
4755 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
4756 em->block_start = bytenr;
4757 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
4760 bytenr += btrfs_file_extent_offset(leaf, item);
4761 em->block_start = bytenr;
4762 em->block_len = em->len;
4763 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
4764 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
4767 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
4771 size_t extent_offset;
4774 em->block_start = EXTENT_MAP_INLINE;
4775 if (!page || create) {
4776 em->start = extent_start;
4777 em->len = extent_end - extent_start;
4781 size = btrfs_file_extent_inline_len(leaf, item);
4782 extent_offset = page_offset(page) + pg_offset - extent_start;
4783 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
4784 size - extent_offset);
4785 em->start = extent_start + extent_offset;
4786 em->len = (copy_size + root->sectorsize - 1) &
4787 ~((u64)root->sectorsize - 1);
4788 em->orig_start = EXTENT_MAP_INLINE;
4790 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
4791 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
4792 if (create == 0 && !PageUptodate(page)) {
4793 if (btrfs_file_extent_compression(leaf, item) ==
4794 BTRFS_COMPRESS_ZLIB) {
4795 ret = uncompress_inline(path, inode, page,
4797 extent_offset, item);
4801 read_extent_buffer(leaf, map + pg_offset, ptr,
4803 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
4804 memset(map + pg_offset + copy_size, 0,
4805 PAGE_CACHE_SIZE - pg_offset -
4810 flush_dcache_page(page);
4811 } else if (create && PageUptodate(page)) {
4814 free_extent_map(em);
4816 btrfs_release_path(root, path);
4817 trans = btrfs_join_transaction(root, 1);
4821 write_extent_buffer(leaf, map + pg_offset, ptr,
4824 btrfs_mark_buffer_dirty(leaf);
4826 set_extent_uptodate(io_tree, em->start,
4827 extent_map_end(em) - 1, GFP_NOFS);
4830 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
4837 em->block_start = EXTENT_MAP_HOLE;
4838 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
4840 btrfs_release_path(root, path);
4841 if (em->start > start || extent_map_end(em) <= start) {
4842 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
4843 "[%llu %llu]\n", (unsigned long long)em->start,
4844 (unsigned long long)em->len,
4845 (unsigned long long)start,
4846 (unsigned long long)len);
4852 write_lock(&em_tree->lock);
4853 ret = add_extent_mapping(em_tree, em);
4854 /* it is possible that someone inserted the extent into the tree
4855 * while we had the lock dropped. It is also possible that
4856 * an overlapping map exists in the tree
4858 if (ret == -EEXIST) {
4859 struct extent_map *existing;
4863 existing = lookup_extent_mapping(em_tree, start, len);
4864 if (existing && (existing->start > start ||
4865 existing->start + existing->len <= start)) {
4866 free_extent_map(existing);
4870 existing = lookup_extent_mapping(em_tree, em->start,
4873 err = merge_extent_mapping(em_tree, existing,
4876 free_extent_map(existing);
4878 free_extent_map(em);
4883 free_extent_map(em);
4887 free_extent_map(em);
4892 write_unlock(&em_tree->lock);
4895 btrfs_free_path(path);
4897 ret = btrfs_end_transaction(trans, root);
4902 free_extent_map(em);
4903 return ERR_PTR(err);
4908 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
4909 const struct iovec *iov, loff_t offset,
4910 unsigned long nr_segs)
4915 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4916 __u64 start, __u64 len)
4918 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent);
4921 int btrfs_readpage(struct file *file, struct page *page)
4923 struct extent_io_tree *tree;
4924 tree = &BTRFS_I(page->mapping->host)->io_tree;
4925 return extent_read_full_page(tree, page, btrfs_get_extent);
4928 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
4930 struct extent_io_tree *tree;
4933 if (current->flags & PF_MEMALLOC) {
4934 redirty_page_for_writepage(wbc, page);
4938 tree = &BTRFS_I(page->mapping->host)->io_tree;
4939 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
4942 int btrfs_writepages(struct address_space *mapping,
4943 struct writeback_control *wbc)
4945 struct extent_io_tree *tree;
4947 tree = &BTRFS_I(mapping->host)->io_tree;
4948 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
4952 btrfs_readpages(struct file *file, struct address_space *mapping,
4953 struct list_head *pages, unsigned nr_pages)
4955 struct extent_io_tree *tree;
4956 tree = &BTRFS_I(mapping->host)->io_tree;
4957 return extent_readpages(tree, mapping, pages, nr_pages,
4960 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
4962 struct extent_io_tree *tree;
4963 struct extent_map_tree *map;
4966 tree = &BTRFS_I(page->mapping->host)->io_tree;
4967 map = &BTRFS_I(page->mapping->host)->extent_tree;
4968 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
4970 ClearPagePrivate(page);
4971 set_page_private(page, 0);
4972 page_cache_release(page);
4977 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
4979 if (PageWriteback(page) || PageDirty(page))
4981 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
4984 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
4986 struct extent_io_tree *tree;
4987 struct btrfs_ordered_extent *ordered;
4988 u64 page_start = page_offset(page);
4989 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
4993 * we have the page locked, so new writeback can't start,
4994 * and the dirty bit won't be cleared while we are here.
4996 * Wait for IO on this page so that we can safely clear
4997 * the PagePrivate2 bit and do ordered accounting
4999 wait_on_page_writeback(page);
5001 tree = &BTRFS_I(page->mapping->host)->io_tree;
5003 btrfs_releasepage(page, GFP_NOFS);
5006 lock_extent(tree, page_start, page_end, GFP_NOFS);
5007 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
5011 * IO on this page will never be started, so we need
5012 * to account for any ordered extents now
5014 clear_extent_bit(tree, page_start, page_end,
5015 EXTENT_DIRTY | EXTENT_DELALLOC |
5016 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
5019 * whoever cleared the private bit is responsible
5020 * for the finish_ordered_io
5022 if (TestClearPagePrivate2(page)) {
5023 btrfs_finish_ordered_io(page->mapping->host,
5024 page_start, page_end);
5026 btrfs_put_ordered_extent(ordered);
5027 lock_extent(tree, page_start, page_end, GFP_NOFS);
5029 clear_extent_bit(tree, page_start, page_end,
5030 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
5031 EXTENT_DO_ACCOUNTING, 1, 1, NULL, GFP_NOFS);
5032 __btrfs_releasepage(page, GFP_NOFS);
5034 ClearPageChecked(page);
5035 if (PagePrivate(page)) {
5036 ClearPagePrivate(page);
5037 set_page_private(page, 0);
5038 page_cache_release(page);
5043 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
5044 * called from a page fault handler when a page is first dirtied. Hence we must
5045 * be careful to check for EOF conditions here. We set the page up correctly
5046 * for a written page which means we get ENOSPC checking when writing into
5047 * holes and correct delalloc and unwritten extent mapping on filesystems that
5048 * support these features.
5050 * We are not allowed to take the i_mutex here so we have to play games to
5051 * protect against truncate races as the page could now be beyond EOF. Because
5052 * vmtruncate() writes the inode size before removing pages, once we have the
5053 * page lock we can determine safely if the page is beyond EOF. If it is not
5054 * beyond EOF, then the page is guaranteed safe against truncation until we
5057 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
5059 struct page *page = vmf->page;
5060 struct inode *inode = fdentry(vma->vm_file)->d_inode;
5061 struct btrfs_root *root = BTRFS_I(inode)->root;
5062 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5063 struct btrfs_ordered_extent *ordered;
5065 unsigned long zero_start;
5071 ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE);
5075 else /* -ENOSPC, -EIO, etc */
5076 ret = VM_FAULT_SIGBUS;
5080 ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
5082 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
5083 ret = VM_FAULT_SIGBUS;
5087 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
5090 size = i_size_read(inode);
5091 page_start = page_offset(page);
5092 page_end = page_start + PAGE_CACHE_SIZE - 1;
5094 if ((page->mapping != inode->i_mapping) ||
5095 (page_start >= size)) {
5096 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
5097 /* page got truncated out from underneath us */
5100 wait_on_page_writeback(page);
5102 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
5103 set_page_extent_mapped(page);
5106 * we can't set the delalloc bits if there are pending ordered
5107 * extents. Drop our locks and wait for them to finish
5109 ordered = btrfs_lookup_ordered_extent(inode, page_start);
5111 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5113 btrfs_start_ordered_extent(inode, ordered, 1);
5114 btrfs_put_ordered_extent(ordered);
5119 * XXX - page_mkwrite gets called every time the page is dirtied, even
5120 * if it was already dirty, so for space accounting reasons we need to
5121 * clear any delalloc bits for the range we are fixing to save. There
5122 * is probably a better way to do this, but for now keep consistent with
5123 * prepare_pages in the normal write path.
5125 clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
5126 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
5129 ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
5131 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5132 ret = VM_FAULT_SIGBUS;
5133 btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
5138 /* page is wholly or partially inside EOF */
5139 if (page_start + PAGE_CACHE_SIZE > size)
5140 zero_start = size & ~PAGE_CACHE_MASK;
5142 zero_start = PAGE_CACHE_SIZE;
5144 if (zero_start != PAGE_CACHE_SIZE) {
5146 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
5147 flush_dcache_page(page);
5150 ClearPageChecked(page);
5151 set_page_dirty(page);
5152 SetPageUptodate(page);
5154 BTRFS_I(inode)->last_trans = root->fs_info->generation;
5155 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
5157 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5160 btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
5162 return VM_FAULT_LOCKED;
5168 static void btrfs_truncate(struct inode *inode)
5170 struct btrfs_root *root = BTRFS_I(inode)->root;
5172 struct btrfs_trans_handle *trans;
5174 u64 mask = root->sectorsize - 1;
5176 if (!S_ISREG(inode->i_mode)) {
5181 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
5185 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
5186 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
5188 trans = btrfs_start_transaction(root, 1);
5189 btrfs_set_trans_block_group(trans, inode);
5192 * setattr is responsible for setting the ordered_data_close flag,
5193 * but that is only tested during the last file release. That
5194 * could happen well after the next commit, leaving a great big
5195 * window where new writes may get lost if someone chooses to write
5196 * to this file after truncating to zero
5198 * The inode doesn't have any dirty data here, and so if we commit
5199 * this is a noop. If someone immediately starts writing to the inode
5200 * it is very likely we'll catch some of their writes in this
5201 * transaction, and the commit will find this file on the ordered
5202 * data list with good things to send down.
5204 * This is a best effort solution, there is still a window where
5205 * using truncate to replace the contents of the file will
5206 * end up with a zero length file after a crash.
5208 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
5209 btrfs_add_ordered_operation(trans, root, inode);
5212 ret = btrfs_truncate_inode_items(trans, root, inode,
5214 BTRFS_EXTENT_DATA_KEY);
5218 ret = btrfs_update_inode(trans, root, inode);
5221 nr = trans->blocks_used;
5222 btrfs_end_transaction(trans, root);
5223 btrfs_btree_balance_dirty(root, nr);
5225 trans = btrfs_start_transaction(root, 1);
5226 btrfs_set_trans_block_group(trans, inode);
5229 if (ret == 0 && inode->i_nlink > 0) {
5230 ret = btrfs_orphan_del(trans, inode);
5234 ret = btrfs_update_inode(trans, root, inode);
5237 nr = trans->blocks_used;
5238 ret = btrfs_end_transaction_throttle(trans, root);
5240 btrfs_btree_balance_dirty(root, nr);
5244 * create a new subvolume directory/inode (helper for the ioctl).
5246 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
5247 struct btrfs_root *new_root,
5248 u64 new_dirid, u64 alloc_hint)
5250 struct inode *inode;
5254 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
5255 new_dirid, alloc_hint, S_IFDIR | 0700, &index);
5257 return PTR_ERR(inode);
5258 inode->i_op = &btrfs_dir_inode_operations;
5259 inode->i_fop = &btrfs_dir_file_operations;
5262 btrfs_i_size_write(inode, 0);
5264 err = btrfs_update_inode(trans, new_root, inode);
5271 /* helper function for file defrag and space balancing. This
5272 * forces readahead on a given range of bytes in an inode
5274 unsigned long btrfs_force_ra(struct address_space *mapping,
5275 struct file_ra_state *ra, struct file *file,
5276 pgoff_t offset, pgoff_t last_index)
5278 pgoff_t req_size = last_index - offset + 1;
5280 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
5281 return offset + req_size;
5284 struct inode *btrfs_alloc_inode(struct super_block *sb)
5286 struct btrfs_inode *ei;
5288 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
5292 ei->last_sub_trans = 0;
5293 ei->logged_trans = 0;
5294 ei->outstanding_extents = 0;
5295 ei->reserved_extents = 0;
5297 spin_lock_init(&ei->accounting_lock);
5298 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
5299 INIT_LIST_HEAD(&ei->i_orphan);
5300 INIT_LIST_HEAD(&ei->ordered_operations);
5301 return &ei->vfs_inode;
5304 void btrfs_destroy_inode(struct inode *inode)
5306 struct btrfs_ordered_extent *ordered;
5307 struct btrfs_root *root = BTRFS_I(inode)->root;
5309 WARN_ON(!list_empty(&inode->i_dentry));
5310 WARN_ON(inode->i_data.nrpages);
5313 * This can happen where we create an inode, but somebody else also
5314 * created the same inode and we need to destroy the one we already
5321 * Make sure we're properly removed from the ordered operation
5325 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
5326 spin_lock(&root->fs_info->ordered_extent_lock);
5327 list_del_init(&BTRFS_I(inode)->ordered_operations);
5328 spin_unlock(&root->fs_info->ordered_extent_lock);
5331 spin_lock(&root->list_lock);
5332 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
5333 printk(KERN_INFO "BTRFS: inode %lu still on the orphan list\n",
5335 list_del_init(&BTRFS_I(inode)->i_orphan);
5337 spin_unlock(&root->list_lock);
5340 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
5344 printk(KERN_ERR "btrfs found ordered "
5345 "extent %llu %llu on inode cleanup\n",
5346 (unsigned long long)ordered->file_offset,
5347 (unsigned long long)ordered->len);
5348 btrfs_remove_ordered_extent(inode, ordered);
5349 btrfs_put_ordered_extent(ordered);
5350 btrfs_put_ordered_extent(ordered);
5353 inode_tree_del(inode);
5354 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
5356 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
5359 void btrfs_drop_inode(struct inode *inode)
5361 struct btrfs_root *root = BTRFS_I(inode)->root;
5363 if (inode->i_nlink > 0 && btrfs_root_refs(&root->root_item) == 0)
5364 generic_delete_inode(inode);
5366 generic_drop_inode(inode);
5369 static void init_once(void *foo)
5371 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
5373 inode_init_once(&ei->vfs_inode);
5376 void btrfs_destroy_cachep(void)
5378 if (btrfs_inode_cachep)
5379 kmem_cache_destroy(btrfs_inode_cachep);
5380 if (btrfs_trans_handle_cachep)
5381 kmem_cache_destroy(btrfs_trans_handle_cachep);
5382 if (btrfs_transaction_cachep)
5383 kmem_cache_destroy(btrfs_transaction_cachep);
5384 if (btrfs_path_cachep)
5385 kmem_cache_destroy(btrfs_path_cachep);
5388 int btrfs_init_cachep(void)
5390 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
5391 sizeof(struct btrfs_inode), 0,
5392 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
5393 if (!btrfs_inode_cachep)
5396 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
5397 sizeof(struct btrfs_trans_handle), 0,
5398 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
5399 if (!btrfs_trans_handle_cachep)
5402 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
5403 sizeof(struct btrfs_transaction), 0,
5404 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
5405 if (!btrfs_transaction_cachep)
5408 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
5409 sizeof(struct btrfs_path), 0,
5410 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
5411 if (!btrfs_path_cachep)
5416 btrfs_destroy_cachep();
5420 static int btrfs_getattr(struct vfsmount *mnt,
5421 struct dentry *dentry, struct kstat *stat)
5423 struct inode *inode = dentry->d_inode;
5424 generic_fillattr(inode, stat);
5425 stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
5426 stat->blksize = PAGE_CACHE_SIZE;
5427 stat->blocks = (inode_get_bytes(inode) +
5428 BTRFS_I(inode)->delalloc_bytes) >> 9;
5432 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
5433 struct inode *new_dir, struct dentry *new_dentry)
5435 struct btrfs_trans_handle *trans;
5436 struct btrfs_root *root = BTRFS_I(old_dir)->root;
5437 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
5438 struct inode *new_inode = new_dentry->d_inode;
5439 struct inode *old_inode = old_dentry->d_inode;
5440 struct timespec ctime = CURRENT_TIME;
5445 if (new_dir->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5448 /* we only allow rename subvolume link between subvolumes */
5449 if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
5452 if (old_inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
5453 (new_inode && new_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID))
5456 if (S_ISDIR(old_inode->i_mode) && new_inode &&
5457 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
5461 * We want to reserve the absolute worst case amount of items. So if
5462 * both inodes are subvols and we need to unlink them then that would
5463 * require 4 item modifications, but if they are both normal inodes it
5464 * would require 5 item modifications, so we'll assume their normal
5465 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
5466 * should cover the worst case number of items we'll modify.
5468 ret = btrfs_reserve_metadata_space(root, 11);
5473 * we're using rename to replace one file with another.
5474 * and the replacement file is large. Start IO on it now so
5475 * we don't add too much work to the end of the transaction
5477 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
5478 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
5479 filemap_flush(old_inode->i_mapping);
5481 /* close the racy window with snapshot create/destroy ioctl */
5482 if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
5483 down_read(&root->fs_info->subvol_sem);
5485 trans = btrfs_start_transaction(root, 1);
5486 btrfs_set_trans_block_group(trans, new_dir);
5489 btrfs_record_root_in_trans(trans, dest);
5491 ret = btrfs_set_inode_index(new_dir, &index);
5495 if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
5496 /* force full log commit if subvolume involved. */
5497 root->fs_info->last_trans_log_full_commit = trans->transid;
5499 ret = btrfs_insert_inode_ref(trans, dest,
5500 new_dentry->d_name.name,
5501 new_dentry->d_name.len,
5503 new_dir->i_ino, index);
5507 * this is an ugly little race, but the rename is required
5508 * to make sure that if we crash, the inode is either at the
5509 * old name or the new one. pinning the log transaction lets
5510 * us make sure we don't allow a log commit to come in after
5511 * we unlink the name but before we add the new name back in.
5513 btrfs_pin_log_trans(root);
5516 * make sure the inode gets flushed if it is replacing
5519 if (new_inode && new_inode->i_size &&
5520 old_inode && S_ISREG(old_inode->i_mode)) {
5521 btrfs_add_ordered_operation(trans, root, old_inode);
5524 old_dir->i_ctime = old_dir->i_mtime = ctime;
5525 new_dir->i_ctime = new_dir->i_mtime = ctime;
5526 old_inode->i_ctime = ctime;
5528 if (old_dentry->d_parent != new_dentry->d_parent)
5529 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
5531 if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
5532 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
5533 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
5534 old_dentry->d_name.name,
5535 old_dentry->d_name.len);
5537 btrfs_inc_nlink(old_dentry->d_inode);
5538 ret = btrfs_unlink_inode(trans, root, old_dir,
5539 old_dentry->d_inode,
5540 old_dentry->d_name.name,
5541 old_dentry->d_name.len);
5546 new_inode->i_ctime = CURRENT_TIME;
5547 if (unlikely(new_inode->i_ino ==
5548 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
5549 root_objectid = BTRFS_I(new_inode)->location.objectid;
5550 ret = btrfs_unlink_subvol(trans, dest, new_dir,
5552 new_dentry->d_name.name,
5553 new_dentry->d_name.len);
5554 BUG_ON(new_inode->i_nlink == 0);
5556 ret = btrfs_unlink_inode(trans, dest, new_dir,
5557 new_dentry->d_inode,
5558 new_dentry->d_name.name,
5559 new_dentry->d_name.len);
5562 if (new_inode->i_nlink == 0) {
5563 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
5568 ret = btrfs_add_link(trans, new_dir, old_inode,
5569 new_dentry->d_name.name,
5570 new_dentry->d_name.len, 0, index);
5573 if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
5574 btrfs_log_new_name(trans, old_inode, old_dir,
5575 new_dentry->d_parent);
5576 btrfs_end_log_trans(root);
5579 btrfs_end_transaction_throttle(trans, root);
5581 if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
5582 up_read(&root->fs_info->subvol_sem);
5584 btrfs_unreserve_metadata_space(root, 11);
5589 * some fairly slow code that needs optimization. This walks the list
5590 * of all the inodes with pending delalloc and forces them to disk.
5592 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
5594 struct list_head *head = &root->fs_info->delalloc_inodes;
5595 struct btrfs_inode *binode;
5596 struct inode *inode;
5598 if (root->fs_info->sb->s_flags & MS_RDONLY)
5601 spin_lock(&root->fs_info->delalloc_lock);
5602 while (!list_empty(head)) {
5603 binode = list_entry(head->next, struct btrfs_inode,
5605 inode = igrab(&binode->vfs_inode);
5607 list_del_init(&binode->delalloc_inodes);
5608 spin_unlock(&root->fs_info->delalloc_lock);
5610 filemap_flush(inode->i_mapping);
5612 btrfs_add_delayed_iput(inode);
5617 spin_lock(&root->fs_info->delalloc_lock);
5619 spin_unlock(&root->fs_info->delalloc_lock);
5621 /* the filemap_flush will queue IO into the worker threads, but
5622 * we have to make sure the IO is actually started and that
5623 * ordered extents get created before we return
5625 atomic_inc(&root->fs_info->async_submit_draining);
5626 while (atomic_read(&root->fs_info->nr_async_submits) ||
5627 atomic_read(&root->fs_info->async_delalloc_pages)) {
5628 wait_event(root->fs_info->async_submit_wait,
5629 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
5630 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
5632 atomic_dec(&root->fs_info->async_submit_draining);
5636 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
5637 const char *symname)
5639 struct btrfs_trans_handle *trans;
5640 struct btrfs_root *root = BTRFS_I(dir)->root;
5641 struct btrfs_path *path;
5642 struct btrfs_key key;
5643 struct inode *inode = NULL;
5651 struct btrfs_file_extent_item *ei;
5652 struct extent_buffer *leaf;
5653 unsigned long nr = 0;
5655 name_len = strlen(symname) + 1;
5656 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
5657 return -ENAMETOOLONG;
5660 * 2 items for inode item and ref
5661 * 2 items for dir items
5662 * 1 item for xattr if selinux is on
5664 err = btrfs_reserve_metadata_space(root, 5);
5668 trans = btrfs_start_transaction(root, 1);
5671 btrfs_set_trans_block_group(trans, dir);
5673 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
5679 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
5681 dentry->d_parent->d_inode->i_ino, objectid,
5682 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO,
5684 err = PTR_ERR(inode);
5688 err = btrfs_init_inode_security(trans, inode, dir);
5694 btrfs_set_trans_block_group(trans, inode);
5695 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
5699 inode->i_mapping->a_ops = &btrfs_aops;
5700 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5701 inode->i_fop = &btrfs_file_operations;
5702 inode->i_op = &btrfs_file_inode_operations;
5703 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
5705 btrfs_update_inode_block_group(trans, inode);
5706 btrfs_update_inode_block_group(trans, dir);
5710 path = btrfs_alloc_path();
5712 key.objectid = inode->i_ino;
5714 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
5715 datasize = btrfs_file_extent_calc_inline_size(name_len);
5716 err = btrfs_insert_empty_item(trans, root, path, &key,
5722 leaf = path->nodes[0];
5723 ei = btrfs_item_ptr(leaf, path->slots[0],
5724 struct btrfs_file_extent_item);
5725 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
5726 btrfs_set_file_extent_type(leaf, ei,
5727 BTRFS_FILE_EXTENT_INLINE);
5728 btrfs_set_file_extent_encryption(leaf, ei, 0);
5729 btrfs_set_file_extent_compression(leaf, ei, 0);
5730 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
5731 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
5733 ptr = btrfs_file_extent_inline_start(ei);
5734 write_extent_buffer(leaf, symname, ptr, name_len);
5735 btrfs_mark_buffer_dirty(leaf);
5736 btrfs_free_path(path);
5738 inode->i_op = &btrfs_symlink_inode_operations;
5739 inode->i_mapping->a_ops = &btrfs_symlink_aops;
5740 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
5741 inode_set_bytes(inode, name_len);
5742 btrfs_i_size_write(inode, name_len - 1);
5743 err = btrfs_update_inode(trans, root, inode);
5748 nr = trans->blocks_used;
5749 btrfs_end_transaction_throttle(trans, root);
5751 btrfs_unreserve_metadata_space(root, 5);
5753 inode_dec_link_count(inode);
5756 btrfs_btree_balance_dirty(root, nr);
5760 static int prealloc_file_range(struct inode *inode, u64 start, u64 end,
5761 u64 alloc_hint, int mode, loff_t actual_len)
5763 struct btrfs_trans_handle *trans;
5764 struct btrfs_root *root = BTRFS_I(inode)->root;
5765 struct btrfs_key ins;
5767 u64 cur_offset = start;
5768 u64 num_bytes = end - start;
5772 while (num_bytes > 0) {
5773 alloc_size = min(num_bytes, root->fs_info->max_extent);
5775 trans = btrfs_start_transaction(root, 1);
5777 ret = btrfs_reserve_extent(trans, root, alloc_size,
5778 root->sectorsize, 0, alloc_hint,
5785 ret = btrfs_reserve_metadata_space(root, 3);
5787 btrfs_free_reserved_extent(root, ins.objectid,
5792 ret = insert_reserved_file_extent(trans, inode,
5793 cur_offset, ins.objectid,
5794 ins.offset, ins.offset,
5795 ins.offset, 0, 0, 0,
5796 BTRFS_FILE_EXTENT_PREALLOC);
5798 btrfs_drop_extent_cache(inode, cur_offset,
5799 cur_offset + ins.offset -1, 0);
5801 num_bytes -= ins.offset;
5802 cur_offset += ins.offset;
5803 alloc_hint = ins.objectid + ins.offset;
5805 inode->i_ctime = CURRENT_TIME;
5806 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
5807 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
5808 (actual_len > inode->i_size) &&
5809 (cur_offset > inode->i_size)) {
5811 if (cur_offset > actual_len)
5812 i_size = actual_len;
5814 i_size = cur_offset;
5815 i_size_write(inode, i_size);
5816 btrfs_ordered_update_i_size(inode, i_size, NULL);
5819 ret = btrfs_update_inode(trans, root, inode);
5822 btrfs_end_transaction(trans, root);
5823 btrfs_unreserve_metadata_space(root, 3);
5828 btrfs_end_transaction(trans, root);
5833 static long btrfs_fallocate(struct inode *inode, int mode,
5834 loff_t offset, loff_t len)
5842 u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
5843 struct extent_map *em;
5846 alloc_start = offset & ~mask;
5847 alloc_end = (offset + len + mask) & ~mask;
5850 * wait for ordered IO before we have any locks. We'll loop again
5851 * below with the locks held.
5853 btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
5855 mutex_lock(&inode->i_mutex);
5856 if (alloc_start > inode->i_size) {
5857 ret = btrfs_cont_expand(inode, alloc_start);
5862 ret = btrfs_check_data_free_space(BTRFS_I(inode)->root, inode,
5863 alloc_end - alloc_start);
5867 locked_end = alloc_end - 1;
5869 struct btrfs_ordered_extent *ordered;
5871 /* the extent lock is ordered inside the running
5874 lock_extent(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
5876 ordered = btrfs_lookup_first_ordered_extent(inode,
5879 ordered->file_offset + ordered->len > alloc_start &&
5880 ordered->file_offset < alloc_end) {
5881 btrfs_put_ordered_extent(ordered);
5882 unlock_extent(&BTRFS_I(inode)->io_tree,
5883 alloc_start, locked_end, GFP_NOFS);
5885 * we can't wait on the range with the transaction
5886 * running or with the extent lock held
5888 btrfs_wait_ordered_range(inode, alloc_start,
5889 alloc_end - alloc_start);
5892 btrfs_put_ordered_extent(ordered);
5897 cur_offset = alloc_start;
5899 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
5900 alloc_end - cur_offset, 0);
5901 BUG_ON(IS_ERR(em) || !em);
5902 last_byte = min(extent_map_end(em), alloc_end);
5903 last_byte = (last_byte + mask) & ~mask;
5904 if (em->block_start == EXTENT_MAP_HOLE ||
5905 (cur_offset >= inode->i_size &&
5906 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5907 ret = prealloc_file_range(inode,
5908 cur_offset, last_byte,
5909 alloc_hint, mode, offset+len);
5911 free_extent_map(em);
5915 if (em->block_start <= EXTENT_MAP_LAST_BYTE)
5916 alloc_hint = em->block_start;
5917 free_extent_map(em);
5919 cur_offset = last_byte;
5920 if (cur_offset >= alloc_end) {
5925 unlock_extent(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
5928 btrfs_free_reserved_data_space(BTRFS_I(inode)->root, inode,
5929 alloc_end - alloc_start);
5931 mutex_unlock(&inode->i_mutex);
5935 static int btrfs_set_page_dirty(struct page *page)
5937 return __set_page_dirty_nobuffers(page);
5940 static int btrfs_permission(struct inode *inode, int mask)
5942 if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE))
5944 return generic_permission(inode, mask, btrfs_check_acl);
5947 static const struct inode_operations btrfs_dir_inode_operations = {
5948 .getattr = btrfs_getattr,
5949 .lookup = btrfs_lookup,
5950 .create = btrfs_create,
5951 .unlink = btrfs_unlink,
5953 .mkdir = btrfs_mkdir,
5954 .rmdir = btrfs_rmdir,
5955 .rename = btrfs_rename,
5956 .symlink = btrfs_symlink,
5957 .setattr = btrfs_setattr,
5958 .mknod = btrfs_mknod,
5959 .setxattr = btrfs_setxattr,
5960 .getxattr = btrfs_getxattr,
5961 .listxattr = btrfs_listxattr,
5962 .removexattr = btrfs_removexattr,
5963 .permission = btrfs_permission,
5965 static const struct inode_operations btrfs_dir_ro_inode_operations = {
5966 .lookup = btrfs_lookup,
5967 .permission = btrfs_permission,
5970 static const struct file_operations btrfs_dir_file_operations = {
5971 .llseek = generic_file_llseek,
5972 .read = generic_read_dir,
5973 .readdir = btrfs_real_readdir,
5974 .unlocked_ioctl = btrfs_ioctl,
5975 #ifdef CONFIG_COMPAT
5976 .compat_ioctl = btrfs_ioctl,
5978 .release = btrfs_release_file,
5979 .fsync = btrfs_sync_file,
5982 static struct extent_io_ops btrfs_extent_io_ops = {
5983 .fill_delalloc = run_delalloc_range,
5984 .submit_bio_hook = btrfs_submit_bio_hook,
5985 .merge_bio_hook = btrfs_merge_bio_hook,
5986 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
5987 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
5988 .writepage_start_hook = btrfs_writepage_start_hook,
5989 .readpage_io_failed_hook = btrfs_io_failed_hook,
5990 .set_bit_hook = btrfs_set_bit_hook,
5991 .clear_bit_hook = btrfs_clear_bit_hook,
5992 .merge_extent_hook = btrfs_merge_extent_hook,
5993 .split_extent_hook = btrfs_split_extent_hook,
5997 * btrfs doesn't support the bmap operation because swapfiles
5998 * use bmap to make a mapping of extents in the file. They assume
5999 * these extents won't change over the life of the file and they
6000 * use the bmap result to do IO directly to the drive.
6002 * the btrfs bmap call would return logical addresses that aren't
6003 * suitable for IO and they also will change frequently as COW
6004 * operations happen. So, swapfile + btrfs == corruption.
6006 * For now we're avoiding this by dropping bmap.
6008 static const struct address_space_operations btrfs_aops = {
6009 .readpage = btrfs_readpage,
6010 .writepage = btrfs_writepage,
6011 .writepages = btrfs_writepages,
6012 .readpages = btrfs_readpages,
6013 .sync_page = block_sync_page,
6014 .direct_IO = btrfs_direct_IO,
6015 .invalidatepage = btrfs_invalidatepage,
6016 .releasepage = btrfs_releasepage,
6017 .set_page_dirty = btrfs_set_page_dirty,
6018 .error_remove_page = generic_error_remove_page,
6021 static const struct address_space_operations btrfs_symlink_aops = {
6022 .readpage = btrfs_readpage,
6023 .writepage = btrfs_writepage,
6024 .invalidatepage = btrfs_invalidatepage,
6025 .releasepage = btrfs_releasepage,
6028 static const struct inode_operations btrfs_file_inode_operations = {
6029 .truncate = btrfs_truncate,
6030 .getattr = btrfs_getattr,
6031 .setattr = btrfs_setattr,
6032 .setxattr = btrfs_setxattr,
6033 .getxattr = btrfs_getxattr,
6034 .listxattr = btrfs_listxattr,
6035 .removexattr = btrfs_removexattr,
6036 .permission = btrfs_permission,
6037 .fallocate = btrfs_fallocate,
6038 .fiemap = btrfs_fiemap,
6040 static const struct inode_operations btrfs_special_inode_operations = {
6041 .getattr = btrfs_getattr,
6042 .setattr = btrfs_setattr,
6043 .permission = btrfs_permission,
6044 .setxattr = btrfs_setxattr,
6045 .getxattr = btrfs_getxattr,
6046 .listxattr = btrfs_listxattr,
6047 .removexattr = btrfs_removexattr,
6049 static const struct inode_operations btrfs_symlink_inode_operations = {
6050 .readlink = generic_readlink,
6051 .follow_link = page_follow_link_light,
6052 .put_link = page_put_link,
6053 .permission = btrfs_permission,
6054 .setxattr = btrfs_setxattr,
6055 .getxattr = btrfs_getxattr,
6056 .listxattr = btrfs_listxattr,
6057 .removexattr = btrfs_removexattr,
6060 const struct dentry_operations btrfs_dentry_operations = {
6061 .d_delete = btrfs_dentry_delete,