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.
20 #include <linux/pagemap.h>
21 #include <linux/highmem.h>
22 #include <linux/time.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/backing-dev.h>
26 #include <linux/mpage.h>
27 #include <linux/aio.h>
28 #include <linux/falloc.h>
29 #include <linux/swap.h>
30 #include <linux/writeback.h>
31 #include <linux/statfs.h>
32 #include <linux/compat.h>
33 #include <linux/slab.h>
34 #include <linux/btrfs.h>
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "print-tree.h"
45 static struct kmem_cache *btrfs_inode_defrag_cachep;
47 * when auto defrag is enabled we
48 * queue up these defrag structs to remember which
49 * inodes need defragging passes
52 struct rb_node rb_node;
56 * transid where the defrag was added, we search for
57 * extents newer than this
64 /* last offset we were able to defrag */
67 /* if we've wrapped around back to zero once already */
71 static int __compare_inode_defrag(struct inode_defrag *defrag1,
72 struct inode_defrag *defrag2)
74 if (defrag1->root > defrag2->root)
76 else if (defrag1->root < defrag2->root)
78 else if (defrag1->ino > defrag2->ino)
80 else if (defrag1->ino < defrag2->ino)
86 /* pop a record for an inode into the defrag tree. The lock
87 * must be held already
89 * If you're inserting a record for an older transid than an
90 * existing record, the transid already in the tree is lowered
92 * If an existing record is found the defrag item you
95 static int __btrfs_add_inode_defrag(struct inode *inode,
96 struct inode_defrag *defrag)
98 struct btrfs_root *root = BTRFS_I(inode)->root;
99 struct inode_defrag *entry;
101 struct rb_node *parent = NULL;
104 p = &root->fs_info->defrag_inodes.rb_node;
107 entry = rb_entry(parent, struct inode_defrag, rb_node);
109 ret = __compare_inode_defrag(defrag, entry);
111 p = &parent->rb_left;
113 p = &parent->rb_right;
115 /* if we're reinserting an entry for
116 * an old defrag run, make sure to
117 * lower the transid of our existing record
119 if (defrag->transid < entry->transid)
120 entry->transid = defrag->transid;
121 if (defrag->last_offset > entry->last_offset)
122 entry->last_offset = defrag->last_offset;
126 set_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
127 rb_link_node(&defrag->rb_node, parent, p);
128 rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes);
132 static inline int __need_auto_defrag(struct btrfs_root *root)
134 if (!btrfs_test_opt(root, AUTO_DEFRAG))
137 if (btrfs_fs_closing(root->fs_info))
144 * insert a defrag record for this inode if auto defrag is
147 int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
150 struct btrfs_root *root = BTRFS_I(inode)->root;
151 struct inode_defrag *defrag;
155 if (!__need_auto_defrag(root))
158 if (test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags))
162 transid = trans->transid;
164 transid = BTRFS_I(inode)->root->last_trans;
166 defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS);
170 defrag->ino = btrfs_ino(inode);
171 defrag->transid = transid;
172 defrag->root = root->root_key.objectid;
174 spin_lock(&root->fs_info->defrag_inodes_lock);
175 if (!test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) {
177 * If we set IN_DEFRAG flag and evict the inode from memory,
178 * and then re-read this inode, this new inode doesn't have
179 * IN_DEFRAG flag. At the case, we may find the existed defrag.
181 ret = __btrfs_add_inode_defrag(inode, defrag);
183 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
185 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
187 spin_unlock(&root->fs_info->defrag_inodes_lock);
192 * Requeue the defrag object. If there is a defrag object that points to
193 * the same inode in the tree, we will merge them together (by
194 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
196 static void btrfs_requeue_inode_defrag(struct inode *inode,
197 struct inode_defrag *defrag)
199 struct btrfs_root *root = BTRFS_I(inode)->root;
202 if (!__need_auto_defrag(root))
206 * Here we don't check the IN_DEFRAG flag, because we need merge
209 spin_lock(&root->fs_info->defrag_inodes_lock);
210 ret = __btrfs_add_inode_defrag(inode, defrag);
211 spin_unlock(&root->fs_info->defrag_inodes_lock);
216 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
220 * pick the defragable inode that we want, if it doesn't exist, we will get
223 static struct inode_defrag *
224 btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino)
226 struct inode_defrag *entry = NULL;
227 struct inode_defrag tmp;
229 struct rb_node *parent = NULL;
235 spin_lock(&fs_info->defrag_inodes_lock);
236 p = fs_info->defrag_inodes.rb_node;
239 entry = rb_entry(parent, struct inode_defrag, rb_node);
241 ret = __compare_inode_defrag(&tmp, entry);
245 p = parent->rb_right;
250 if (parent && __compare_inode_defrag(&tmp, entry) > 0) {
251 parent = rb_next(parent);
253 entry = rb_entry(parent, struct inode_defrag, rb_node);
259 rb_erase(parent, &fs_info->defrag_inodes);
260 spin_unlock(&fs_info->defrag_inodes_lock);
264 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info)
266 struct inode_defrag *defrag;
267 struct rb_node *node;
269 spin_lock(&fs_info->defrag_inodes_lock);
270 node = rb_first(&fs_info->defrag_inodes);
272 rb_erase(node, &fs_info->defrag_inodes);
273 defrag = rb_entry(node, struct inode_defrag, rb_node);
274 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
276 if (need_resched()) {
277 spin_unlock(&fs_info->defrag_inodes_lock);
279 spin_lock(&fs_info->defrag_inodes_lock);
282 node = rb_first(&fs_info->defrag_inodes);
284 spin_unlock(&fs_info->defrag_inodes_lock);
287 #define BTRFS_DEFRAG_BATCH 1024
289 static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
290 struct inode_defrag *defrag)
292 struct btrfs_root *inode_root;
294 struct btrfs_key key;
295 struct btrfs_ioctl_defrag_range_args range;
301 key.objectid = defrag->root;
302 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
303 key.offset = (u64)-1;
305 index = srcu_read_lock(&fs_info->subvol_srcu);
307 inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
308 if (IS_ERR(inode_root)) {
309 ret = PTR_ERR(inode_root);
313 if (btrfs_root_refs(&inode_root->root_item) == 0) {
318 key.objectid = defrag->ino;
319 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
321 inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
323 ret = PTR_ERR(inode);
326 srcu_read_unlock(&fs_info->subvol_srcu, index);
328 /* do a chunk of defrag */
329 clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
330 memset(&range, 0, sizeof(range));
332 range.start = defrag->last_offset;
334 sb_start_write(fs_info->sb);
335 num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
337 sb_end_write(fs_info->sb);
339 * if we filled the whole defrag batch, there
340 * must be more work to do. Queue this defrag
343 if (num_defrag == BTRFS_DEFRAG_BATCH) {
344 defrag->last_offset = range.start;
345 btrfs_requeue_inode_defrag(inode, defrag);
346 } else if (defrag->last_offset && !defrag->cycled) {
348 * we didn't fill our defrag batch, but
349 * we didn't start at zero. Make sure we loop
350 * around to the start of the file.
352 defrag->last_offset = 0;
354 btrfs_requeue_inode_defrag(inode, defrag);
356 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
362 srcu_read_unlock(&fs_info->subvol_srcu, index);
363 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
368 * run through the list of inodes in the FS that need
371 int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
373 struct inode_defrag *defrag;
375 u64 root_objectid = 0;
377 atomic_inc(&fs_info->defrag_running);
379 /* Pause the auto defragger. */
380 if (test_bit(BTRFS_FS_STATE_REMOUNTING,
384 if (!__need_auto_defrag(fs_info->tree_root))
387 /* find an inode to defrag */
388 defrag = btrfs_pick_defrag_inode(fs_info, root_objectid,
391 if (root_objectid || first_ino) {
400 first_ino = defrag->ino + 1;
401 root_objectid = defrag->root;
403 __btrfs_run_defrag_inode(fs_info, defrag);
405 atomic_dec(&fs_info->defrag_running);
408 * during unmount, we use the transaction_wait queue to
409 * wait for the defragger to stop
411 wake_up(&fs_info->transaction_wait);
415 /* simple helper to fault in pages and copy. This should go away
416 * and be replaced with calls into generic code.
418 static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
420 struct page **prepared_pages,
424 size_t total_copied = 0;
426 int offset = pos & (PAGE_CACHE_SIZE - 1);
428 while (write_bytes > 0) {
429 size_t count = min_t(size_t,
430 PAGE_CACHE_SIZE - offset, write_bytes);
431 struct page *page = prepared_pages[pg];
433 * Copy data from userspace to the current page
435 * Disable pagefault to avoid recursive lock since
436 * the pages are already locked
439 copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
442 /* Flush processor's dcache for this page */
443 flush_dcache_page(page);
446 * if we get a partial write, we can end up with
447 * partially up to date pages. These add
448 * a lot of complexity, so make sure they don't
449 * happen by forcing this copy to be retried.
451 * The rest of the btrfs_file_write code will fall
452 * back to page at a time copies after we return 0.
454 if (!PageUptodate(page) && copied < count)
457 iov_iter_advance(i, copied);
458 write_bytes -= copied;
459 total_copied += copied;
461 /* Return to btrfs_file_aio_write to fault page */
462 if (unlikely(copied == 0))
465 if (unlikely(copied < PAGE_CACHE_SIZE - offset)) {
476 * unlocks pages after btrfs_file_write is done with them
478 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
481 for (i = 0; i < num_pages; i++) {
482 /* page checked is some magic around finding pages that
483 * have been modified without going through btrfs_set_page_dirty
486 ClearPageChecked(pages[i]);
487 unlock_page(pages[i]);
488 mark_page_accessed(pages[i]);
489 page_cache_release(pages[i]);
494 * after copy_from_user, pages need to be dirtied and we need to make
495 * sure holes are created between the current EOF and the start of
496 * any next extents (if required).
498 * this also makes the decision about creating an inline extent vs
499 * doing real data extents, marking pages dirty and delalloc as required.
501 int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
502 struct page **pages, size_t num_pages,
503 loff_t pos, size_t write_bytes,
504 struct extent_state **cached)
510 u64 end_of_last_block;
511 u64 end_pos = pos + write_bytes;
512 loff_t isize = i_size_read(inode);
514 start_pos = pos & ~((u64)root->sectorsize - 1);
515 num_bytes = ALIGN(write_bytes + pos - start_pos, root->sectorsize);
517 end_of_last_block = start_pos + num_bytes - 1;
518 err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
523 for (i = 0; i < num_pages; i++) {
524 struct page *p = pages[i];
531 * we've only changed i_size in ram, and we haven't updated
532 * the disk i_size. There is no need to log the inode
536 i_size_write(inode, end_pos);
541 * this drops all the extents in the cache that intersect the range
542 * [start, end]. Existing extents are split as required.
544 void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
547 struct extent_map *em;
548 struct extent_map *split = NULL;
549 struct extent_map *split2 = NULL;
550 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
551 u64 len = end - start + 1;
559 WARN_ON(end < start);
560 if (end == (u64)-1) {
569 split = alloc_extent_map();
571 split2 = alloc_extent_map();
572 if (!split || !split2)
575 write_lock(&em_tree->lock);
576 em = lookup_extent_mapping(em_tree, start, len);
578 write_unlock(&em_tree->lock);
582 gen = em->generation;
583 if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
584 if (testend && em->start + em->len >= start + len) {
586 write_unlock(&em_tree->lock);
589 start = em->start + em->len;
591 len = start + len - (em->start + em->len);
593 write_unlock(&em_tree->lock);
596 compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
597 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
598 clear_bit(EXTENT_FLAG_LOGGING, &flags);
599 modified = !list_empty(&em->list);
600 remove_extent_mapping(em_tree, em);
604 if (em->start < start) {
605 split->start = em->start;
606 split->len = start - em->start;
608 if (em->block_start < EXTENT_MAP_LAST_BYTE) {
609 split->orig_start = em->orig_start;
610 split->block_start = em->block_start;
613 split->block_len = em->block_len;
615 split->block_len = split->len;
616 split->orig_block_len = max(split->block_len,
618 split->ram_bytes = em->ram_bytes;
620 split->orig_start = split->start;
621 split->block_len = 0;
622 split->block_start = em->block_start;
623 split->orig_block_len = 0;
624 split->ram_bytes = split->len;
627 split->generation = gen;
628 split->bdev = em->bdev;
629 split->flags = flags;
630 split->compress_type = em->compress_type;
631 ret = add_extent_mapping(em_tree, split, modified);
632 BUG_ON(ret); /* Logic error */
633 free_extent_map(split);
637 if (testend && em->start + em->len > start + len) {
638 u64 diff = start + len - em->start;
640 split->start = start + len;
641 split->len = em->start + em->len - (start + len);
642 split->bdev = em->bdev;
643 split->flags = flags;
644 split->compress_type = em->compress_type;
645 split->generation = gen;
647 if (em->block_start < EXTENT_MAP_LAST_BYTE) {
648 split->orig_block_len = max(em->block_len,
651 split->ram_bytes = em->ram_bytes;
653 split->block_len = em->block_len;
654 split->block_start = em->block_start;
655 split->orig_start = em->orig_start;
657 split->block_len = split->len;
658 split->block_start = em->block_start
660 split->orig_start = em->orig_start;
663 split->ram_bytes = split->len;
664 split->orig_start = split->start;
665 split->block_len = 0;
666 split->block_start = em->block_start;
667 split->orig_block_len = 0;
670 ret = add_extent_mapping(em_tree, split, modified);
671 BUG_ON(ret); /* Logic error */
672 free_extent_map(split);
676 write_unlock(&em_tree->lock);
680 /* once for the tree*/
684 free_extent_map(split);
686 free_extent_map(split2);
690 * this is very complex, but the basic idea is to drop all extents
691 * in the range start - end. hint_block is filled in with a block number
692 * that would be a good hint to the block allocator for this file.
694 * If an extent intersects the range but is not entirely inside the range
695 * it is either truncated or split. Anything entirely inside the range
696 * is deleted from the tree.
698 int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
699 struct btrfs_root *root, struct inode *inode,
700 struct btrfs_path *path, u64 start, u64 end,
701 u64 *drop_end, int drop_cache)
703 struct extent_buffer *leaf;
704 struct btrfs_file_extent_item *fi;
705 struct btrfs_key key;
706 struct btrfs_key new_key;
707 u64 ino = btrfs_ino(inode);
708 u64 search_start = start;
711 u64 extent_offset = 0;
718 int modify_tree = -1;
719 int update_refs = (root->ref_cows || root == root->fs_info->tree_root);
723 btrfs_drop_extent_cache(inode, start, end - 1, 0);
725 if (start >= BTRFS_I(inode)->disk_i_size)
730 ret = btrfs_lookup_file_extent(trans, root, path, ino,
731 search_start, modify_tree);
734 if (ret > 0 && path->slots[0] > 0 && search_start == start) {
735 leaf = path->nodes[0];
736 btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
737 if (key.objectid == ino &&
738 key.type == BTRFS_EXTENT_DATA_KEY)
743 leaf = path->nodes[0];
744 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
746 ret = btrfs_next_leaf(root, path);
753 leaf = path->nodes[0];
757 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
758 if (key.objectid > ino ||
759 key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
762 fi = btrfs_item_ptr(leaf, path->slots[0],
763 struct btrfs_file_extent_item);
764 extent_type = btrfs_file_extent_type(leaf, fi);
766 if (extent_type == BTRFS_FILE_EXTENT_REG ||
767 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
768 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
769 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
770 extent_offset = btrfs_file_extent_offset(leaf, fi);
771 extent_end = key.offset +
772 btrfs_file_extent_num_bytes(leaf, fi);
773 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
774 extent_end = key.offset +
775 btrfs_file_extent_inline_len(leaf, fi);
778 extent_end = search_start;
781 if (extent_end <= search_start) {
787 search_start = max(key.offset, start);
788 if (recow || !modify_tree) {
790 btrfs_release_path(path);
795 * | - range to drop - |
796 * | -------- extent -------- |
798 if (start > key.offset && end < extent_end) {
800 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
802 memcpy(&new_key, &key, sizeof(new_key));
803 new_key.offset = start;
804 ret = btrfs_duplicate_item(trans, root, path,
806 if (ret == -EAGAIN) {
807 btrfs_release_path(path);
813 leaf = path->nodes[0];
814 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
815 struct btrfs_file_extent_item);
816 btrfs_set_file_extent_num_bytes(leaf, fi,
819 fi = btrfs_item_ptr(leaf, path->slots[0],
820 struct btrfs_file_extent_item);
822 extent_offset += start - key.offset;
823 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
824 btrfs_set_file_extent_num_bytes(leaf, fi,
826 btrfs_mark_buffer_dirty(leaf);
828 if (update_refs && disk_bytenr > 0) {
829 ret = btrfs_inc_extent_ref(trans, root,
830 disk_bytenr, num_bytes, 0,
831 root->root_key.objectid,
833 start - extent_offset, 0);
834 BUG_ON(ret); /* -ENOMEM */
839 * | ---- range to drop ----- |
840 * | -------- extent -------- |
842 if (start <= key.offset && end < extent_end) {
843 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
845 memcpy(&new_key, &key, sizeof(new_key));
846 new_key.offset = end;
847 btrfs_set_item_key_safe(root, path, &new_key);
849 extent_offset += end - key.offset;
850 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
851 btrfs_set_file_extent_num_bytes(leaf, fi,
853 btrfs_mark_buffer_dirty(leaf);
854 if (update_refs && disk_bytenr > 0)
855 inode_sub_bytes(inode, end - key.offset);
859 search_start = extent_end;
861 * | ---- range to drop ----- |
862 * | -------- extent -------- |
864 if (start > key.offset && end >= extent_end) {
866 BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
868 btrfs_set_file_extent_num_bytes(leaf, fi,
870 btrfs_mark_buffer_dirty(leaf);
871 if (update_refs && disk_bytenr > 0)
872 inode_sub_bytes(inode, extent_end - start);
873 if (end == extent_end)
881 * | ---- range to drop ----- |
882 * | ------ extent ------ |
884 if (start <= key.offset && end >= extent_end) {
886 del_slot = path->slots[0];
889 BUG_ON(del_slot + del_nr != path->slots[0]);
894 extent_type == BTRFS_FILE_EXTENT_INLINE) {
895 inode_sub_bytes(inode,
896 extent_end - key.offset);
897 extent_end = ALIGN(extent_end,
899 } else if (update_refs && disk_bytenr > 0) {
900 ret = btrfs_free_extent(trans, root,
901 disk_bytenr, num_bytes, 0,
902 root->root_key.objectid,
903 key.objectid, key.offset -
905 BUG_ON(ret); /* -ENOMEM */
906 inode_sub_bytes(inode,
907 extent_end - key.offset);
910 if (end == extent_end)
913 if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) {
918 ret = btrfs_del_items(trans, root, path, del_slot,
921 btrfs_abort_transaction(trans, root, ret);
928 btrfs_release_path(path);
935 if (!ret && del_nr > 0) {
936 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
938 btrfs_abort_transaction(trans, root, ret);
942 *drop_end = found ? min(end, extent_end) : end;
943 btrfs_release_path(path);
947 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
948 struct btrfs_root *root, struct inode *inode, u64 start,
949 u64 end, int drop_cache)
951 struct btrfs_path *path;
954 path = btrfs_alloc_path();
957 ret = __btrfs_drop_extents(trans, root, inode, path, start, end, NULL,
959 btrfs_free_path(path);
963 static int extent_mergeable(struct extent_buffer *leaf, int slot,
964 u64 objectid, u64 bytenr, u64 orig_offset,
965 u64 *start, u64 *end)
967 struct btrfs_file_extent_item *fi;
968 struct btrfs_key key;
971 if (slot < 0 || slot >= btrfs_header_nritems(leaf))
974 btrfs_item_key_to_cpu(leaf, &key, slot);
975 if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
978 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
979 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG ||
980 btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr ||
981 btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset ||
982 btrfs_file_extent_compression(leaf, fi) ||
983 btrfs_file_extent_encryption(leaf, fi) ||
984 btrfs_file_extent_other_encoding(leaf, fi))
987 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
988 if ((*start && *start != key.offset) || (*end && *end != extent_end))
997 * Mark extent in the range start - end as written.
999 * This changes extent type from 'pre-allocated' to 'regular'. If only
1000 * part of extent is marked as written, the extent will be split into
1003 int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
1004 struct inode *inode, u64 start, u64 end)
1006 struct btrfs_root *root = BTRFS_I(inode)->root;
1007 struct extent_buffer *leaf;
1008 struct btrfs_path *path;
1009 struct btrfs_file_extent_item *fi;
1010 struct btrfs_key key;
1011 struct btrfs_key new_key;
1023 u64 ino = btrfs_ino(inode);
1025 path = btrfs_alloc_path();
1032 key.type = BTRFS_EXTENT_DATA_KEY;
1035 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1038 if (ret > 0 && path->slots[0] > 0)
1041 leaf = path->nodes[0];
1042 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1043 BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY);
1044 fi = btrfs_item_ptr(leaf, path->slots[0],
1045 struct btrfs_file_extent_item);
1046 BUG_ON(btrfs_file_extent_type(leaf, fi) !=
1047 BTRFS_FILE_EXTENT_PREALLOC);
1048 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
1049 BUG_ON(key.offset > start || extent_end < end);
1051 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1052 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
1053 orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi);
1054 memcpy(&new_key, &key, sizeof(new_key));
1056 if (start == key.offset && end < extent_end) {
1059 if (extent_mergeable(leaf, path->slots[0] - 1,
1060 ino, bytenr, orig_offset,
1061 &other_start, &other_end)) {
1062 new_key.offset = end;
1063 btrfs_set_item_key_safe(root, path, &new_key);
1064 fi = btrfs_item_ptr(leaf, path->slots[0],
1065 struct btrfs_file_extent_item);
1066 btrfs_set_file_extent_generation(leaf, fi,
1068 btrfs_set_file_extent_num_bytes(leaf, fi,
1070 btrfs_set_file_extent_offset(leaf, fi,
1072 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
1073 struct btrfs_file_extent_item);
1074 btrfs_set_file_extent_generation(leaf, fi,
1076 btrfs_set_file_extent_num_bytes(leaf, fi,
1078 btrfs_mark_buffer_dirty(leaf);
1083 if (start > key.offset && end == extent_end) {
1086 if (extent_mergeable(leaf, path->slots[0] + 1,
1087 ino, bytenr, orig_offset,
1088 &other_start, &other_end)) {
1089 fi = btrfs_item_ptr(leaf, path->slots[0],
1090 struct btrfs_file_extent_item);
1091 btrfs_set_file_extent_num_bytes(leaf, fi,
1092 start - key.offset);
1093 btrfs_set_file_extent_generation(leaf, fi,
1096 new_key.offset = start;
1097 btrfs_set_item_key_safe(root, path, &new_key);
1099 fi = btrfs_item_ptr(leaf, path->slots[0],
1100 struct btrfs_file_extent_item);
1101 btrfs_set_file_extent_generation(leaf, fi,
1103 btrfs_set_file_extent_num_bytes(leaf, fi,
1105 btrfs_set_file_extent_offset(leaf, fi,
1106 start - orig_offset);
1107 btrfs_mark_buffer_dirty(leaf);
1112 while (start > key.offset || end < extent_end) {
1113 if (key.offset == start)
1116 new_key.offset = split;
1117 ret = btrfs_duplicate_item(trans, root, path, &new_key);
1118 if (ret == -EAGAIN) {
1119 btrfs_release_path(path);
1123 btrfs_abort_transaction(trans, root, ret);
1127 leaf = path->nodes[0];
1128 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
1129 struct btrfs_file_extent_item);
1130 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1131 btrfs_set_file_extent_num_bytes(leaf, fi,
1132 split - key.offset);
1134 fi = btrfs_item_ptr(leaf, path->slots[0],
1135 struct btrfs_file_extent_item);
1137 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1138 btrfs_set_file_extent_offset(leaf, fi, split - orig_offset);
1139 btrfs_set_file_extent_num_bytes(leaf, fi,
1140 extent_end - split);
1141 btrfs_mark_buffer_dirty(leaf);
1143 ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
1144 root->root_key.objectid,
1145 ino, orig_offset, 0);
1146 BUG_ON(ret); /* -ENOMEM */
1148 if (split == start) {
1151 BUG_ON(start != key.offset);
1160 if (extent_mergeable(leaf, path->slots[0] + 1,
1161 ino, bytenr, orig_offset,
1162 &other_start, &other_end)) {
1164 btrfs_release_path(path);
1167 extent_end = other_end;
1168 del_slot = path->slots[0] + 1;
1170 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
1171 0, root->root_key.objectid,
1172 ino, orig_offset, 0);
1173 BUG_ON(ret); /* -ENOMEM */
1177 if (extent_mergeable(leaf, path->slots[0] - 1,
1178 ino, bytenr, orig_offset,
1179 &other_start, &other_end)) {
1181 btrfs_release_path(path);
1184 key.offset = other_start;
1185 del_slot = path->slots[0];
1187 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
1188 0, root->root_key.objectid,
1189 ino, orig_offset, 0);
1190 BUG_ON(ret); /* -ENOMEM */
1193 fi = btrfs_item_ptr(leaf, path->slots[0],
1194 struct btrfs_file_extent_item);
1195 btrfs_set_file_extent_type(leaf, fi,
1196 BTRFS_FILE_EXTENT_REG);
1197 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1198 btrfs_mark_buffer_dirty(leaf);
1200 fi = btrfs_item_ptr(leaf, del_slot - 1,
1201 struct btrfs_file_extent_item);
1202 btrfs_set_file_extent_type(leaf, fi,
1203 BTRFS_FILE_EXTENT_REG);
1204 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1205 btrfs_set_file_extent_num_bytes(leaf, fi,
1206 extent_end - key.offset);
1207 btrfs_mark_buffer_dirty(leaf);
1209 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
1211 btrfs_abort_transaction(trans, root, ret);
1216 btrfs_free_path(path);
1221 * on error we return an unlocked page and the error value
1222 * on success we return a locked page and 0
1224 static int prepare_uptodate_page(struct page *page, u64 pos,
1225 bool force_uptodate)
1229 if (((pos & (PAGE_CACHE_SIZE - 1)) || force_uptodate) &&
1230 !PageUptodate(page)) {
1231 ret = btrfs_readpage(NULL, page);
1235 if (!PageUptodate(page)) {
1244 * this gets pages into the page cache and locks them down, it also properly
1245 * waits for data=ordered extents to finish before allowing the pages to be
1248 static noinline int prepare_pages(struct btrfs_root *root, struct file *file,
1249 struct page **pages, size_t num_pages,
1250 loff_t pos, unsigned long first_index,
1251 size_t write_bytes, bool force_uptodate)
1253 struct extent_state *cached_state = NULL;
1255 unsigned long index = pos >> PAGE_CACHE_SHIFT;
1256 struct inode *inode = file_inode(file);
1257 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1263 start_pos = pos & ~((u64)root->sectorsize - 1);
1264 last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
1267 for (i = 0; i < num_pages; i++) {
1268 pages[i] = find_or_create_page(inode->i_mapping, index + i,
1269 mask | __GFP_WRITE);
1277 err = prepare_uptodate_page(pages[i], pos,
1279 if (i == num_pages - 1)
1280 err = prepare_uptodate_page(pages[i],
1281 pos + write_bytes, false);
1283 page_cache_release(pages[i]);
1287 wait_on_page_writeback(pages[i]);
1290 if (start_pos < inode->i_size) {
1291 struct btrfs_ordered_extent *ordered;
1292 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1293 start_pos, last_pos - 1, 0, &cached_state);
1294 ordered = btrfs_lookup_first_ordered_extent(inode,
1297 ordered->file_offset + ordered->len > start_pos &&
1298 ordered->file_offset < last_pos) {
1299 btrfs_put_ordered_extent(ordered);
1300 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1301 start_pos, last_pos - 1,
1302 &cached_state, GFP_NOFS);
1303 for (i = 0; i < num_pages; i++) {
1304 unlock_page(pages[i]);
1305 page_cache_release(pages[i]);
1307 btrfs_wait_ordered_range(inode, start_pos,
1308 last_pos - start_pos);
1312 btrfs_put_ordered_extent(ordered);
1314 clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos,
1315 last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1316 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
1317 0, 0, &cached_state, GFP_NOFS);
1318 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1319 start_pos, last_pos - 1, &cached_state,
1322 for (i = 0; i < num_pages; i++) {
1323 if (clear_page_dirty_for_io(pages[i]))
1324 account_page_redirty(pages[i]);
1325 set_page_extent_mapped(pages[i]);
1326 WARN_ON(!PageLocked(pages[i]));
1330 while (faili >= 0) {
1331 unlock_page(pages[faili]);
1332 page_cache_release(pages[faili]);
1339 static noinline int check_can_nocow(struct inode *inode, loff_t pos,
1340 size_t *write_bytes)
1342 struct btrfs_root *root = BTRFS_I(inode)->root;
1343 struct btrfs_ordered_extent *ordered;
1344 u64 lockstart, lockend;
1348 lockstart = round_down(pos, root->sectorsize);
1349 lockend = lockstart + round_up(*write_bytes, root->sectorsize) - 1;
1352 lock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
1353 ordered = btrfs_lookup_ordered_range(inode, lockstart,
1354 lockend - lockstart + 1);
1358 unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
1359 btrfs_start_ordered_extent(inode, ordered, 1);
1360 btrfs_put_ordered_extent(ordered);
1363 num_bytes = lockend - lockstart + 1;
1364 ret = can_nocow_extent(inode, lockstart, &num_bytes, NULL, NULL, NULL);
1368 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
1369 EXTENT_DIRTY | EXTENT_DELALLOC |
1370 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1372 *write_bytes = min_t(size_t, *write_bytes, num_bytes);
1375 unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
1380 static noinline ssize_t __btrfs_buffered_write(struct file *file,
1384 struct inode *inode = file_inode(file);
1385 struct btrfs_root *root = BTRFS_I(inode)->root;
1386 struct page **pages = NULL;
1387 u64 release_bytes = 0;
1388 unsigned long first_index;
1389 size_t num_written = 0;
1392 bool only_release_metadata = false;
1393 bool force_page_uptodate = false;
1395 nrptrs = min((iov_iter_count(i) + PAGE_CACHE_SIZE - 1) /
1396 PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
1397 (sizeof(struct page *)));
1398 nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied);
1399 nrptrs = max(nrptrs, 8);
1400 pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
1404 first_index = pos >> PAGE_CACHE_SHIFT;
1406 while (iov_iter_count(i) > 0) {
1407 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
1408 size_t write_bytes = min(iov_iter_count(i),
1409 nrptrs * (size_t)PAGE_CACHE_SIZE -
1411 size_t num_pages = (write_bytes + offset +
1412 PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1413 size_t reserve_bytes;
1417 WARN_ON(num_pages > nrptrs);
1420 * Fault pages before locking them in prepare_pages
1421 * to avoid recursive lock
1423 if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) {
1428 reserve_bytes = num_pages << PAGE_CACHE_SHIFT;
1429 ret = btrfs_check_data_free_space(inode, reserve_bytes);
1430 if (ret == -ENOSPC &&
1431 (BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
1432 BTRFS_INODE_PREALLOC))) {
1433 ret = check_can_nocow(inode, pos, &write_bytes);
1435 only_release_metadata = true;
1437 * our prealloc extent may be smaller than
1438 * write_bytes, so scale down.
1440 num_pages = (write_bytes + offset +
1441 PAGE_CACHE_SIZE - 1) >>
1443 reserve_bytes = num_pages << PAGE_CACHE_SHIFT;
1453 ret = btrfs_delalloc_reserve_metadata(inode, reserve_bytes);
1455 if (!only_release_metadata)
1456 btrfs_free_reserved_data_space(inode,
1461 release_bytes = reserve_bytes;
1464 * This is going to setup the pages array with the number of
1465 * pages we want, so we don't really need to worry about the
1466 * contents of pages from loop to loop
1468 ret = prepare_pages(root, file, pages, num_pages,
1469 pos, first_index, write_bytes,
1470 force_page_uptodate);
1474 copied = btrfs_copy_from_user(pos, num_pages,
1475 write_bytes, pages, i);
1478 * if we have trouble faulting in the pages, fall
1479 * back to one page at a time
1481 if (copied < write_bytes)
1485 force_page_uptodate = true;
1488 force_page_uptodate = false;
1489 dirty_pages = (copied + offset +
1490 PAGE_CACHE_SIZE - 1) >>
1495 * If we had a short copy we need to release the excess delaloc
1496 * bytes we reserved. We need to increment outstanding_extents
1497 * because btrfs_delalloc_release_space will decrement it, but
1498 * we still have an outstanding extent for the chunk we actually
1501 if (num_pages > dirty_pages) {
1502 release_bytes = (num_pages - dirty_pages) <<
1505 spin_lock(&BTRFS_I(inode)->lock);
1506 BTRFS_I(inode)->outstanding_extents++;
1507 spin_unlock(&BTRFS_I(inode)->lock);
1509 if (only_release_metadata)
1510 btrfs_delalloc_release_metadata(inode,
1513 btrfs_delalloc_release_space(inode,
1517 release_bytes = dirty_pages << PAGE_CACHE_SHIFT;
1519 ret = btrfs_dirty_pages(root, inode, pages,
1520 dirty_pages, pos, copied,
1523 btrfs_drop_pages(pages, num_pages);
1529 btrfs_drop_pages(pages, num_pages);
1531 if (only_release_metadata && copied > 0) {
1532 u64 lockstart = round_down(pos, root->sectorsize);
1533 u64 lockend = lockstart +
1534 (dirty_pages << PAGE_CACHE_SHIFT) - 1;
1536 set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
1537 lockend, EXTENT_NORESERVE, NULL,
1539 only_release_metadata = false;
1544 balance_dirty_pages_ratelimited(inode->i_mapping);
1545 if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
1546 btrfs_btree_balance_dirty(root);
1549 num_written += copied;
1554 if (release_bytes) {
1555 if (only_release_metadata)
1556 btrfs_delalloc_release_metadata(inode, release_bytes);
1558 btrfs_delalloc_release_space(inode, release_bytes);
1561 return num_written ? num_written : ret;
1564 static ssize_t __btrfs_direct_write(struct kiocb *iocb,
1565 const struct iovec *iov,
1566 unsigned long nr_segs, loff_t pos,
1567 loff_t *ppos, size_t count, size_t ocount)
1569 struct file *file = iocb->ki_filp;
1572 ssize_t written_buffered;
1576 written = generic_file_direct_write(iocb, iov, &nr_segs, pos, ppos,
1579 if (written < 0 || written == count)
1584 iov_iter_init(&i, iov, nr_segs, count, written);
1585 written_buffered = __btrfs_buffered_write(file, &i, pos);
1586 if (written_buffered < 0) {
1587 err = written_buffered;
1590 endbyte = pos + written_buffered - 1;
1591 err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte);
1594 written += written_buffered;
1595 *ppos = pos + written_buffered;
1596 invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT,
1597 endbyte >> PAGE_CACHE_SHIFT);
1599 return written ? written : err;
1602 static void update_time_for_write(struct inode *inode)
1604 struct timespec now;
1606 if (IS_NOCMTIME(inode))
1609 now = current_fs_time(inode->i_sb);
1610 if (!timespec_equal(&inode->i_mtime, &now))
1611 inode->i_mtime = now;
1613 if (!timespec_equal(&inode->i_ctime, &now))
1614 inode->i_ctime = now;
1616 if (IS_I_VERSION(inode))
1617 inode_inc_iversion(inode);
1620 static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
1621 const struct iovec *iov,
1622 unsigned long nr_segs, loff_t pos)
1624 struct file *file = iocb->ki_filp;
1625 struct inode *inode = file_inode(file);
1626 struct btrfs_root *root = BTRFS_I(inode)->root;
1627 loff_t *ppos = &iocb->ki_pos;
1629 ssize_t num_written = 0;
1631 size_t count, ocount;
1632 bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
1634 mutex_lock(&inode->i_mutex);
1636 err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
1638 mutex_unlock(&inode->i_mutex);
1643 current->backing_dev_info = inode->i_mapping->backing_dev_info;
1644 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
1646 mutex_unlock(&inode->i_mutex);
1651 mutex_unlock(&inode->i_mutex);
1655 err = file_remove_suid(file);
1657 mutex_unlock(&inode->i_mutex);
1662 * If BTRFS flips readonly due to some impossible error
1663 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1664 * although we have opened a file as writable, we have
1665 * to stop this write operation to ensure FS consistency.
1667 if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) {
1668 mutex_unlock(&inode->i_mutex);
1674 * We reserve space for updating the inode when we reserve space for the
1675 * extent we are going to write, so we will enospc out there. We don't
1676 * need to start yet another transaction to update the inode as we will
1677 * update the inode when we finish writing whatever data we write.
1679 update_time_for_write(inode);
1681 start_pos = round_down(pos, root->sectorsize);
1682 if (start_pos > i_size_read(inode)) {
1683 err = btrfs_cont_expand(inode, i_size_read(inode), start_pos);
1685 mutex_unlock(&inode->i_mutex);
1691 atomic_inc(&BTRFS_I(inode)->sync_writers);
1693 if (unlikely(file->f_flags & O_DIRECT)) {
1694 num_written = __btrfs_direct_write(iocb, iov, nr_segs,
1695 pos, ppos, count, ocount);
1699 iov_iter_init(&i, iov, nr_segs, count, num_written);
1701 num_written = __btrfs_buffered_write(file, &i, pos);
1702 if (num_written > 0)
1703 *ppos = pos + num_written;
1706 mutex_unlock(&inode->i_mutex);
1709 * we want to make sure fsync finds this change
1710 * but we haven't joined a transaction running right now.
1712 * Later on, someone is sure to update the inode and get the
1713 * real transid recorded.
1715 * We set last_trans now to the fs_info generation + 1,
1716 * this will either be one more than the running transaction
1717 * or the generation used for the next transaction if there isn't
1718 * one running right now.
1720 * We also have to set last_sub_trans to the current log transid,
1721 * otherwise subsequent syncs to a file that's been synced in this
1722 * transaction will appear to have already occured.
1724 BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
1725 BTRFS_I(inode)->last_sub_trans = root->log_transid;
1726 if (num_written > 0 || num_written == -EIOCBQUEUED) {
1727 err = generic_write_sync(file, pos, num_written);
1728 if (err < 0 && num_written > 0)
1733 atomic_dec(&BTRFS_I(inode)->sync_writers);
1735 current->backing_dev_info = NULL;
1736 return num_written ? num_written : err;
1739 int btrfs_release_file(struct inode *inode, struct file *filp)
1742 * ordered_data_close is set by settattr when we are about to truncate
1743 * a file from a non-zero size to a zero size. This tries to
1744 * flush down new bytes that may have been written if the
1745 * application were using truncate to replace a file in place.
1747 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
1748 &BTRFS_I(inode)->runtime_flags)) {
1749 struct btrfs_trans_handle *trans;
1750 struct btrfs_root *root = BTRFS_I(inode)->root;
1753 * We need to block on a committing transaction to keep us from
1754 * throwing a ordered operation on to the list and causing
1755 * something like sync to deadlock trying to flush out this
1758 trans = btrfs_start_transaction(root, 0);
1760 return PTR_ERR(trans);
1761 btrfs_add_ordered_operation(trans, BTRFS_I(inode)->root, inode);
1762 btrfs_end_transaction(trans, root);
1763 if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
1764 filemap_flush(inode->i_mapping);
1766 if (filp->private_data)
1767 btrfs_ioctl_trans_end(filp);
1772 * fsync call for both files and directories. This logs the inode into
1773 * the tree log instead of forcing full commits whenever possible.
1775 * It needs to call filemap_fdatawait so that all ordered extent updates are
1776 * in the metadata btree are up to date for copying to the log.
1778 * It drops the inode mutex before doing the tree log commit. This is an
1779 * important optimization for directories because holding the mutex prevents
1780 * new operations on the dir while we write to disk.
1782 int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
1784 struct dentry *dentry = file->f_path.dentry;
1785 struct inode *inode = dentry->d_inode;
1786 struct btrfs_root *root = BTRFS_I(inode)->root;
1788 struct btrfs_trans_handle *trans;
1791 trace_btrfs_sync_file(file, datasync);
1794 * We write the dirty pages in the range and wait until they complete
1795 * out of the ->i_mutex. If so, we can flush the dirty pages by
1796 * multi-task, and make the performance up. See
1797 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
1799 atomic_inc(&BTRFS_I(inode)->sync_writers);
1800 ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
1801 if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1802 &BTRFS_I(inode)->runtime_flags))
1803 ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
1804 atomic_dec(&BTRFS_I(inode)->sync_writers);
1808 mutex_lock(&inode->i_mutex);
1811 * We flush the dirty pages again to avoid some dirty pages in the
1814 atomic_inc(&root->log_batch);
1815 full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
1816 &BTRFS_I(inode)->runtime_flags);
1818 btrfs_wait_ordered_range(inode, start, end - start + 1);
1819 atomic_inc(&root->log_batch);
1822 * check the transaction that last modified this inode
1823 * and see if its already been committed
1825 if (!BTRFS_I(inode)->last_trans) {
1826 mutex_unlock(&inode->i_mutex);
1831 * if the last transaction that changed this file was before
1832 * the current transaction, we can bail out now without any
1836 if (btrfs_inode_in_log(inode, root->fs_info->generation) ||
1837 BTRFS_I(inode)->last_trans <=
1838 root->fs_info->last_trans_committed) {
1839 BTRFS_I(inode)->last_trans = 0;
1842 * We'v had everything committed since the last time we were
1843 * modified so clear this flag in case it was set for whatever
1844 * reason, it's no longer relevant.
1846 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
1847 &BTRFS_I(inode)->runtime_flags);
1848 mutex_unlock(&inode->i_mutex);
1853 * ok we haven't committed the transaction yet, lets do a commit
1855 if (file->private_data)
1856 btrfs_ioctl_trans_end(file);
1858 trans = btrfs_start_transaction(root, 0);
1859 if (IS_ERR(trans)) {
1860 ret = PTR_ERR(trans);
1861 mutex_unlock(&inode->i_mutex);
1865 ret = btrfs_log_dentry_safe(trans, root, dentry);
1867 mutex_unlock(&inode->i_mutex);
1871 /* we've logged all the items and now have a consistent
1872 * version of the file in the log. It is possible that
1873 * someone will come in and modify the file, but that's
1874 * fine because the log is consistent on disk, and we
1875 * have references to all of the file's extents
1877 * It is possible that someone will come in and log the
1878 * file again, but that will end up using the synchronization
1879 * inside btrfs_sync_log to keep things safe.
1881 mutex_unlock(&inode->i_mutex);
1883 if (ret != BTRFS_NO_LOG_SYNC) {
1886 * If we didn't already wait for ordered extents we need
1890 btrfs_wait_ordered_range(inode, start,
1892 ret = btrfs_commit_transaction(trans, root);
1894 ret = btrfs_sync_log(trans, root);
1896 ret = btrfs_end_transaction(trans, root);
1899 btrfs_wait_ordered_range(inode, start,
1902 ret = btrfs_commit_transaction(trans, root);
1906 ret = btrfs_end_transaction(trans, root);
1909 return ret > 0 ? -EIO : ret;
1912 static const struct vm_operations_struct btrfs_file_vm_ops = {
1913 .fault = filemap_fault,
1914 .page_mkwrite = btrfs_page_mkwrite,
1915 .remap_pages = generic_file_remap_pages,
1918 static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
1920 struct address_space *mapping = filp->f_mapping;
1922 if (!mapping->a_ops->readpage)
1925 file_accessed(filp);
1926 vma->vm_ops = &btrfs_file_vm_ops;
1931 static int hole_mergeable(struct inode *inode, struct extent_buffer *leaf,
1932 int slot, u64 start, u64 end)
1934 struct btrfs_file_extent_item *fi;
1935 struct btrfs_key key;
1937 if (slot < 0 || slot >= btrfs_header_nritems(leaf))
1940 btrfs_item_key_to_cpu(leaf, &key, slot);
1941 if (key.objectid != btrfs_ino(inode) ||
1942 key.type != BTRFS_EXTENT_DATA_KEY)
1945 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
1947 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
1950 if (btrfs_file_extent_disk_bytenr(leaf, fi))
1953 if (key.offset == end)
1955 if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start)
1960 static int fill_holes(struct btrfs_trans_handle *trans, struct inode *inode,
1961 struct btrfs_path *path, u64 offset, u64 end)
1963 struct btrfs_root *root = BTRFS_I(inode)->root;
1964 struct extent_buffer *leaf;
1965 struct btrfs_file_extent_item *fi;
1966 struct extent_map *hole_em;
1967 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1968 struct btrfs_key key;
1971 key.objectid = btrfs_ino(inode);
1972 key.type = BTRFS_EXTENT_DATA_KEY;
1973 key.offset = offset;
1976 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1981 leaf = path->nodes[0];
1982 if (hole_mergeable(inode, leaf, path->slots[0]-1, offset, end)) {
1986 fi = btrfs_item_ptr(leaf, path->slots[0],
1987 struct btrfs_file_extent_item);
1988 num_bytes = btrfs_file_extent_num_bytes(leaf, fi) +
1990 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1991 btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
1992 btrfs_set_file_extent_offset(leaf, fi, 0);
1993 btrfs_mark_buffer_dirty(leaf);
1997 if (hole_mergeable(inode, leaf, path->slots[0]+1, offset, end)) {
2001 key.offset = offset;
2002 btrfs_set_item_key_safe(root, path, &key);
2003 fi = btrfs_item_ptr(leaf, path->slots[0],
2004 struct btrfs_file_extent_item);
2005 num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end -
2007 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2008 btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
2009 btrfs_set_file_extent_offset(leaf, fi, 0);
2010 btrfs_mark_buffer_dirty(leaf);
2013 btrfs_release_path(path);
2015 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset,
2016 0, 0, end - offset, 0, end - offset,
2022 btrfs_release_path(path);
2024 hole_em = alloc_extent_map();
2026 btrfs_drop_extent_cache(inode, offset, end - 1, 0);
2027 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2028 &BTRFS_I(inode)->runtime_flags);
2030 hole_em->start = offset;
2031 hole_em->len = end - offset;
2032 hole_em->ram_bytes = hole_em->len;
2033 hole_em->orig_start = offset;
2035 hole_em->block_start = EXTENT_MAP_HOLE;
2036 hole_em->block_len = 0;
2037 hole_em->orig_block_len = 0;
2038 hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
2039 hole_em->compress_type = BTRFS_COMPRESS_NONE;
2040 hole_em->generation = trans->transid;
2043 btrfs_drop_extent_cache(inode, offset, end - 1, 0);
2044 write_lock(&em_tree->lock);
2045 ret = add_extent_mapping(em_tree, hole_em, 1);
2046 write_unlock(&em_tree->lock);
2047 } while (ret == -EEXIST);
2048 free_extent_map(hole_em);
2050 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2051 &BTRFS_I(inode)->runtime_flags);
2057 static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
2059 struct btrfs_root *root = BTRFS_I(inode)->root;
2060 struct extent_state *cached_state = NULL;
2061 struct btrfs_path *path;
2062 struct btrfs_block_rsv *rsv;
2063 struct btrfs_trans_handle *trans;
2064 u64 lockstart = round_up(offset, BTRFS_I(inode)->root->sectorsize);
2065 u64 lockend = round_down(offset + len,
2066 BTRFS_I(inode)->root->sectorsize) - 1;
2067 u64 cur_offset = lockstart;
2068 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
2072 bool same_page = ((offset >> PAGE_CACHE_SHIFT) ==
2073 ((offset + len - 1) >> PAGE_CACHE_SHIFT));
2075 btrfs_wait_ordered_range(inode, offset, len);
2077 mutex_lock(&inode->i_mutex);
2079 * We needn't truncate any page which is beyond the end of the file
2080 * because we are sure there is no data there.
2083 * Only do this if we are in the same page and we aren't doing the
2086 if (same_page && len < PAGE_CACHE_SIZE) {
2087 if (offset < round_up(inode->i_size, PAGE_CACHE_SIZE))
2088 ret = btrfs_truncate_page(inode, offset, len, 0);
2089 mutex_unlock(&inode->i_mutex);
2093 /* zero back part of the first page */
2094 if (offset < round_up(inode->i_size, PAGE_CACHE_SIZE)) {
2095 ret = btrfs_truncate_page(inode, offset, 0, 0);
2097 mutex_unlock(&inode->i_mutex);
2102 /* zero the front end of the last page */
2103 if (offset + len < round_up(inode->i_size, PAGE_CACHE_SIZE)) {
2104 ret = btrfs_truncate_page(inode, offset + len, 0, 1);
2106 mutex_unlock(&inode->i_mutex);
2111 if (lockend < lockstart) {
2112 mutex_unlock(&inode->i_mutex);
2117 struct btrfs_ordered_extent *ordered;
2119 truncate_pagecache_range(inode, lockstart, lockend);
2121 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
2123 ordered = btrfs_lookup_first_ordered_extent(inode, lockend);
2126 * We need to make sure we have no ordered extents in this range
2127 * and nobody raced in and read a page in this range, if we did
2128 * we need to try again.
2131 (ordered->file_offset + ordered->len < lockstart ||
2132 ordered->file_offset > lockend)) &&
2133 !test_range_bit(&BTRFS_I(inode)->io_tree, lockstart,
2134 lockend, EXTENT_UPTODATE, 0,
2137 btrfs_put_ordered_extent(ordered);
2141 btrfs_put_ordered_extent(ordered);
2142 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
2143 lockend, &cached_state, GFP_NOFS);
2144 btrfs_wait_ordered_range(inode, lockstart,
2145 lockend - lockstart + 1);
2148 path = btrfs_alloc_path();
2154 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
2159 rsv->size = btrfs_calc_trunc_metadata_size(root, 1);
2163 * 1 - update the inode
2164 * 1 - removing the extents in the range
2165 * 1 - adding the hole extent
2167 trans = btrfs_start_transaction(root, 3);
2168 if (IS_ERR(trans)) {
2169 err = PTR_ERR(trans);
2173 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
2176 trans->block_rsv = rsv;
2178 while (cur_offset < lockend) {
2179 ret = __btrfs_drop_extents(trans, root, inode, path,
2180 cur_offset, lockend + 1,
2185 trans->block_rsv = &root->fs_info->trans_block_rsv;
2187 ret = fill_holes(trans, inode, path, cur_offset, drop_end);
2193 cur_offset = drop_end;
2195 ret = btrfs_update_inode(trans, root, inode);
2201 btrfs_end_transaction(trans, root);
2202 btrfs_btree_balance_dirty(root);
2204 trans = btrfs_start_transaction(root, 3);
2205 if (IS_ERR(trans)) {
2206 ret = PTR_ERR(trans);
2211 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
2213 BUG_ON(ret); /* shouldn't happen */
2214 trans->block_rsv = rsv;
2222 trans->block_rsv = &root->fs_info->trans_block_rsv;
2223 ret = fill_holes(trans, inode, path, cur_offset, drop_end);
2233 inode_inc_iversion(inode);
2234 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2236 trans->block_rsv = &root->fs_info->trans_block_rsv;
2237 ret = btrfs_update_inode(trans, root, inode);
2238 btrfs_end_transaction(trans, root);
2239 btrfs_btree_balance_dirty(root);
2241 btrfs_free_path(path);
2242 btrfs_free_block_rsv(root, rsv);
2244 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
2245 &cached_state, GFP_NOFS);
2246 mutex_unlock(&inode->i_mutex);
2252 static long btrfs_fallocate(struct file *file, int mode,
2253 loff_t offset, loff_t len)
2255 struct inode *inode = file_inode(file);
2256 struct extent_state *cached_state = NULL;
2257 struct btrfs_root *root = BTRFS_I(inode)->root;
2264 struct extent_map *em;
2265 int blocksize = BTRFS_I(inode)->root->sectorsize;
2268 alloc_start = round_down(offset, blocksize);
2269 alloc_end = round_up(offset + len, blocksize);
2271 /* Make sure we aren't being give some crap mode */
2272 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
2275 if (mode & FALLOC_FL_PUNCH_HOLE)
2276 return btrfs_punch_hole(inode, offset, len);
2279 * Make sure we have enough space before we do the
2282 ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start);
2285 if (root->fs_info->quota_enabled) {
2286 ret = btrfs_qgroup_reserve(root, alloc_end - alloc_start);
2288 goto out_reserve_fail;
2291 mutex_lock(&inode->i_mutex);
2292 ret = inode_newsize_ok(inode, alloc_end);
2296 if (alloc_start > inode->i_size) {
2297 ret = btrfs_cont_expand(inode, i_size_read(inode),
2303 * If we are fallocating from the end of the file onward we
2304 * need to zero out the end of the page if i_size lands in the
2307 ret = btrfs_truncate_page(inode, inode->i_size, 0, 0);
2313 * wait for ordered IO before we have any locks. We'll loop again
2314 * below with the locks held.
2316 btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
2318 locked_end = alloc_end - 1;
2320 struct btrfs_ordered_extent *ordered;
2322 /* the extent lock is ordered inside the running
2325 lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
2326 locked_end, 0, &cached_state);
2327 ordered = btrfs_lookup_first_ordered_extent(inode,
2330 ordered->file_offset + ordered->len > alloc_start &&
2331 ordered->file_offset < alloc_end) {
2332 btrfs_put_ordered_extent(ordered);
2333 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
2334 alloc_start, locked_end,
2335 &cached_state, GFP_NOFS);
2337 * we can't wait on the range with the transaction
2338 * running or with the extent lock held
2340 btrfs_wait_ordered_range(inode, alloc_start,
2341 alloc_end - alloc_start);
2344 btrfs_put_ordered_extent(ordered);
2349 cur_offset = alloc_start;
2353 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
2354 alloc_end - cur_offset, 0);
2355 if (IS_ERR_OR_NULL(em)) {
2362 last_byte = min(extent_map_end(em), alloc_end);
2363 actual_end = min_t(u64, extent_map_end(em), offset + len);
2364 last_byte = ALIGN(last_byte, blocksize);
2366 if (em->block_start == EXTENT_MAP_HOLE ||
2367 (cur_offset >= inode->i_size &&
2368 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
2369 ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
2370 last_byte - cur_offset,
2371 1 << inode->i_blkbits,
2376 free_extent_map(em);
2379 } else if (actual_end > inode->i_size &&
2380 !(mode & FALLOC_FL_KEEP_SIZE)) {
2382 * We didn't need to allocate any more space, but we
2383 * still extended the size of the file so we need to
2386 inode->i_ctime = CURRENT_TIME;
2387 i_size_write(inode, actual_end);
2388 btrfs_ordered_update_i_size(inode, actual_end, NULL);
2390 free_extent_map(em);
2392 cur_offset = last_byte;
2393 if (cur_offset >= alloc_end) {
2398 unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
2399 &cached_state, GFP_NOFS);
2401 mutex_unlock(&inode->i_mutex);
2402 if (root->fs_info->quota_enabled)
2403 btrfs_qgroup_free(root, alloc_end - alloc_start);
2405 /* Let go of our reservation. */
2406 btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
2410 static int find_desired_extent(struct inode *inode, loff_t *offset, int whence)
2412 struct btrfs_root *root = BTRFS_I(inode)->root;
2413 struct extent_map *em;
2414 struct extent_state *cached_state = NULL;
2415 u64 lockstart = *offset;
2416 u64 lockend = i_size_read(inode);
2417 u64 start = *offset;
2418 u64 orig_start = *offset;
2419 u64 len = i_size_read(inode);
2423 lockend = max_t(u64, root->sectorsize, lockend);
2424 if (lockend <= lockstart)
2425 lockend = lockstart + root->sectorsize;
2428 len = lockend - lockstart + 1;
2430 len = max_t(u64, len, root->sectorsize);
2431 if (inode->i_size == 0)
2434 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0,
2438 * Delalloc is such a pain. If we have a hole and we have pending
2439 * delalloc for a portion of the hole we will get back a hole that
2440 * exists for the entire range since it hasn't been actually written
2441 * yet. So to take care of this case we need to look for an extent just
2442 * before the position we want in case there is outstanding delalloc
2445 if (whence == SEEK_HOLE && start != 0) {
2446 if (start <= root->sectorsize)
2447 em = btrfs_get_extent_fiemap(inode, NULL, 0, 0,
2448 root->sectorsize, 0);
2450 em = btrfs_get_extent_fiemap(inode, NULL, 0,
2451 start - root->sectorsize,
2452 root->sectorsize, 0);
2457 last_end = em->start + em->len;
2458 if (em->block_start == EXTENT_MAP_DELALLOC)
2459 last_end = min_t(u64, last_end, inode->i_size);
2460 free_extent_map(em);
2464 em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0);
2470 if (em->block_start == EXTENT_MAP_HOLE) {
2471 if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) {
2472 if (last_end <= orig_start) {
2473 free_extent_map(em);
2479 if (whence == SEEK_HOLE) {
2481 free_extent_map(em);
2485 if (whence == SEEK_DATA) {
2486 if (em->block_start == EXTENT_MAP_DELALLOC) {
2487 if (start >= inode->i_size) {
2488 free_extent_map(em);
2494 if (!test_bit(EXTENT_FLAG_PREALLOC,
2497 free_extent_map(em);
2503 start = em->start + em->len;
2504 last_end = em->start + em->len;
2506 if (em->block_start == EXTENT_MAP_DELALLOC)
2507 last_end = min_t(u64, last_end, inode->i_size);
2509 if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) {
2510 free_extent_map(em);
2514 free_extent_map(em);
2518 *offset = min(*offset, inode->i_size);
2520 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
2521 &cached_state, GFP_NOFS);
2525 static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence)
2527 struct inode *inode = file->f_mapping->host;
2530 mutex_lock(&inode->i_mutex);
2534 offset = generic_file_llseek(file, offset, whence);
2538 if (offset >= i_size_read(inode)) {
2539 mutex_unlock(&inode->i_mutex);
2543 ret = find_desired_extent(inode, &offset, whence);
2545 mutex_unlock(&inode->i_mutex);
2550 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
2552 mutex_unlock(&inode->i_mutex);
2556 const struct file_operations btrfs_file_operations = {
2557 .llseek = btrfs_file_llseek,
2558 .read = do_sync_read,
2559 .write = do_sync_write,
2560 .aio_read = generic_file_aio_read,
2561 .splice_read = generic_file_splice_read,
2562 .aio_write = btrfs_file_aio_write,
2563 .mmap = btrfs_file_mmap,
2564 .open = generic_file_open,
2565 .release = btrfs_release_file,
2566 .fsync = btrfs_sync_file,
2567 .fallocate = btrfs_fallocate,
2568 .unlocked_ioctl = btrfs_ioctl,
2569 #ifdef CONFIG_COMPAT
2570 .compat_ioctl = btrfs_ioctl,
2574 void btrfs_auto_defrag_exit(void)
2576 if (btrfs_inode_defrag_cachep)
2577 kmem_cache_destroy(btrfs_inode_defrag_cachep);
2580 int btrfs_auto_defrag_init(void)
2582 btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
2583 sizeof(struct inode_defrag), 0,
2584 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
2586 if (!btrfs_inode_defrag_cachep)