1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
7 #include <linux/pagemap.h>
8 #include <linux/time.h>
9 #include <linux/init.h>
10 #include <linux/string.h>
11 #include <linux/backing-dev.h>
12 #include <linux/falloc.h>
13 #include <linux/writeback.h>
14 #include <linux/compat.h>
15 #include <linux/slab.h>
16 #include <linux/btrfs.h>
17 #include <linux/uio.h>
18 #include <linux/iversion.h>
21 #include "transaction.h"
22 #include "btrfs_inode.h"
23 #include "print-tree.h"
28 #include "compression.h"
29 #include "delalloc-space.h"
32 static struct kmem_cache *btrfs_inode_defrag_cachep;
34 * when auto defrag is enabled we
35 * queue up these defrag structs to remember which
36 * inodes need defragging passes
39 struct rb_node rb_node;
43 * transid where the defrag was added, we search for
44 * extents newer than this
51 /* last offset we were able to defrag */
54 /* if we've wrapped around back to zero once already */
58 static int __compare_inode_defrag(struct inode_defrag *defrag1,
59 struct inode_defrag *defrag2)
61 if (defrag1->root > defrag2->root)
63 else if (defrag1->root < defrag2->root)
65 else if (defrag1->ino > defrag2->ino)
67 else if (defrag1->ino < defrag2->ino)
73 /* pop a record for an inode into the defrag tree. The lock
74 * must be held already
76 * If you're inserting a record for an older transid than an
77 * existing record, the transid already in the tree is lowered
79 * If an existing record is found the defrag item you
82 static int __btrfs_add_inode_defrag(struct btrfs_inode *inode,
83 struct inode_defrag *defrag)
85 struct btrfs_fs_info *fs_info = inode->root->fs_info;
86 struct inode_defrag *entry;
88 struct rb_node *parent = NULL;
91 p = &fs_info->defrag_inodes.rb_node;
94 entry = rb_entry(parent, struct inode_defrag, rb_node);
96 ret = __compare_inode_defrag(defrag, entry);
100 p = &parent->rb_right;
102 /* if we're reinserting an entry for
103 * an old defrag run, make sure to
104 * lower the transid of our existing record
106 if (defrag->transid < entry->transid)
107 entry->transid = defrag->transid;
108 if (defrag->last_offset > entry->last_offset)
109 entry->last_offset = defrag->last_offset;
113 set_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags);
114 rb_link_node(&defrag->rb_node, parent, p);
115 rb_insert_color(&defrag->rb_node, &fs_info->defrag_inodes);
119 static inline int __need_auto_defrag(struct btrfs_fs_info *fs_info)
121 if (!btrfs_test_opt(fs_info, AUTO_DEFRAG))
124 if (btrfs_fs_closing(fs_info))
131 * insert a defrag record for this inode if auto defrag is
134 int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
135 struct btrfs_inode *inode)
137 struct btrfs_root *root = inode->root;
138 struct btrfs_fs_info *fs_info = root->fs_info;
139 struct inode_defrag *defrag;
143 if (!__need_auto_defrag(fs_info))
146 if (test_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags))
150 transid = trans->transid;
152 transid = inode->root->last_trans;
154 defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS);
158 defrag->ino = btrfs_ino(inode);
159 defrag->transid = transid;
160 defrag->root = root->root_key.objectid;
162 spin_lock(&fs_info->defrag_inodes_lock);
163 if (!test_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags)) {
165 * If we set IN_DEFRAG flag and evict the inode from memory,
166 * and then re-read this inode, this new inode doesn't have
167 * IN_DEFRAG flag. At the case, we may find the existed defrag.
169 ret = __btrfs_add_inode_defrag(inode, defrag);
171 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
173 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
175 spin_unlock(&fs_info->defrag_inodes_lock);
180 * Requeue the defrag object. If there is a defrag object that points to
181 * the same inode in the tree, we will merge them together (by
182 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
184 static void btrfs_requeue_inode_defrag(struct btrfs_inode *inode,
185 struct inode_defrag *defrag)
187 struct btrfs_fs_info *fs_info = inode->root->fs_info;
190 if (!__need_auto_defrag(fs_info))
194 * Here we don't check the IN_DEFRAG flag, because we need merge
197 spin_lock(&fs_info->defrag_inodes_lock);
198 ret = __btrfs_add_inode_defrag(inode, defrag);
199 spin_unlock(&fs_info->defrag_inodes_lock);
204 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
208 * pick the defragable inode that we want, if it doesn't exist, we will get
211 static struct inode_defrag *
212 btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino)
214 struct inode_defrag *entry = NULL;
215 struct inode_defrag tmp;
217 struct rb_node *parent = NULL;
223 spin_lock(&fs_info->defrag_inodes_lock);
224 p = fs_info->defrag_inodes.rb_node;
227 entry = rb_entry(parent, struct inode_defrag, rb_node);
229 ret = __compare_inode_defrag(&tmp, entry);
233 p = parent->rb_right;
238 if (parent && __compare_inode_defrag(&tmp, entry) > 0) {
239 parent = rb_next(parent);
241 entry = rb_entry(parent, struct inode_defrag, rb_node);
247 rb_erase(parent, &fs_info->defrag_inodes);
248 spin_unlock(&fs_info->defrag_inodes_lock);
252 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info)
254 struct inode_defrag *defrag;
255 struct rb_node *node;
257 spin_lock(&fs_info->defrag_inodes_lock);
258 node = rb_first(&fs_info->defrag_inodes);
260 rb_erase(node, &fs_info->defrag_inodes);
261 defrag = rb_entry(node, struct inode_defrag, rb_node);
262 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
264 cond_resched_lock(&fs_info->defrag_inodes_lock);
266 node = rb_first(&fs_info->defrag_inodes);
268 spin_unlock(&fs_info->defrag_inodes_lock);
271 #define BTRFS_DEFRAG_BATCH 1024
273 static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
274 struct inode_defrag *defrag)
276 struct btrfs_root *inode_root;
278 struct btrfs_ioctl_defrag_range_args range;
283 inode_root = btrfs_get_fs_root(fs_info, defrag->root, true);
284 if (IS_ERR(inode_root)) {
285 ret = PTR_ERR(inode_root);
289 inode = btrfs_iget(fs_info->sb, defrag->ino, inode_root);
290 btrfs_put_root(inode_root);
292 ret = PTR_ERR(inode);
296 /* do a chunk of defrag */
297 clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
298 memset(&range, 0, sizeof(range));
300 range.start = defrag->last_offset;
302 sb_start_write(fs_info->sb);
303 num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
305 sb_end_write(fs_info->sb);
307 * if we filled the whole defrag batch, there
308 * must be more work to do. Queue this defrag
311 if (num_defrag == BTRFS_DEFRAG_BATCH) {
312 defrag->last_offset = range.start;
313 btrfs_requeue_inode_defrag(BTRFS_I(inode), defrag);
314 } else if (defrag->last_offset && !defrag->cycled) {
316 * we didn't fill our defrag batch, but
317 * we didn't start at zero. Make sure we loop
318 * around to the start of the file.
320 defrag->last_offset = 0;
322 btrfs_requeue_inode_defrag(BTRFS_I(inode), defrag);
324 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
330 kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
335 * run through the list of inodes in the FS that need
338 int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
340 struct inode_defrag *defrag;
342 u64 root_objectid = 0;
344 atomic_inc(&fs_info->defrag_running);
346 /* Pause the auto defragger. */
347 if (test_bit(BTRFS_FS_STATE_REMOUNTING,
351 if (!__need_auto_defrag(fs_info))
354 /* find an inode to defrag */
355 defrag = btrfs_pick_defrag_inode(fs_info, root_objectid,
358 if (root_objectid || first_ino) {
367 first_ino = defrag->ino + 1;
368 root_objectid = defrag->root;
370 __btrfs_run_defrag_inode(fs_info, defrag);
372 atomic_dec(&fs_info->defrag_running);
375 * during unmount, we use the transaction_wait queue to
376 * wait for the defragger to stop
378 wake_up(&fs_info->transaction_wait);
382 /* simple helper to fault in pages and copy. This should go away
383 * and be replaced with calls into generic code.
385 static noinline int btrfs_copy_from_user(loff_t pos, size_t write_bytes,
386 struct page **prepared_pages,
390 size_t total_copied = 0;
392 int offset = offset_in_page(pos);
394 while (write_bytes > 0) {
395 size_t count = min_t(size_t,
396 PAGE_SIZE - offset, write_bytes);
397 struct page *page = prepared_pages[pg];
399 * Copy data from userspace to the current page
401 copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
403 /* Flush processor's dcache for this page */
404 flush_dcache_page(page);
407 * if we get a partial write, we can end up with
408 * partially up to date pages. These add
409 * a lot of complexity, so make sure they don't
410 * happen by forcing this copy to be retried.
412 * The rest of the btrfs_file_write code will fall
413 * back to page at a time copies after we return 0.
415 if (!PageUptodate(page) && copied < count)
418 iov_iter_advance(i, copied);
419 write_bytes -= copied;
420 total_copied += copied;
422 /* Return to btrfs_file_write_iter to fault page */
423 if (unlikely(copied == 0))
426 if (copied < PAGE_SIZE - offset) {
437 * unlocks pages after btrfs_file_write is done with them
439 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
442 for (i = 0; i < num_pages; i++) {
443 /* page checked is some magic around finding pages that
444 * have been modified without going through btrfs_set_page_dirty
445 * clear it here. There should be no need to mark the pages
446 * accessed as prepare_pages should have marked them accessed
447 * in prepare_pages via find_or_create_page()
449 ClearPageChecked(pages[i]);
450 unlock_page(pages[i]);
455 static int btrfs_find_new_delalloc_bytes(struct btrfs_inode *inode,
458 struct extent_state **cached_state)
460 u64 search_start = start;
461 const u64 end = start + len - 1;
463 while (search_start < end) {
464 const u64 search_len = end - search_start + 1;
465 struct extent_map *em;
469 em = btrfs_get_extent(inode, NULL, 0, search_start, search_len);
473 if (em->block_start != EXTENT_MAP_HOLE)
477 if (em->start < search_start)
478 em_len -= search_start - em->start;
479 if (em_len > search_len)
482 ret = set_extent_bit(&inode->io_tree, search_start,
483 search_start + em_len - 1,
485 NULL, cached_state, GFP_NOFS);
487 search_start = extent_map_end(em);
496 * after copy_from_user, pages need to be dirtied and we need to make
497 * sure holes are created between the current EOF and the start of
498 * any next extents (if required).
500 * this also makes the decision about creating an inline extent vs
501 * doing real data extents, marking pages dirty and delalloc as required.
503 int btrfs_dirty_pages(struct btrfs_inode *inode, struct page **pages,
504 size_t num_pages, loff_t pos, size_t write_bytes,
505 struct extent_state **cached)
507 struct btrfs_fs_info *fs_info = inode->root->fs_info;
512 u64 end_of_last_block;
513 u64 end_pos = pos + write_bytes;
514 loff_t isize = i_size_read(&inode->vfs_inode);
515 unsigned int extra_bits = 0;
517 start_pos = pos & ~((u64) fs_info->sectorsize - 1);
518 num_bytes = round_up(write_bytes + pos - start_pos,
519 fs_info->sectorsize);
521 end_of_last_block = start_pos + num_bytes - 1;
524 * The pages may have already been dirty, clear out old accounting so
525 * we can set things up properly
527 clear_extent_bit(&inode->io_tree, start_pos, end_of_last_block,
528 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
531 if (!btrfs_is_free_space_inode(inode)) {
532 if (start_pos >= isize &&
533 !(inode->flags & BTRFS_INODE_PREALLOC)) {
535 * There can't be any extents following eof in this case
536 * so just set the delalloc new bit for the range
539 extra_bits |= EXTENT_DELALLOC_NEW;
541 err = btrfs_find_new_delalloc_bytes(inode, start_pos,
548 err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
553 for (i = 0; i < num_pages; i++) {
554 struct page *p = pages[i];
561 * we've only changed i_size in ram, and we haven't updated
562 * the disk i_size. There is no need to log the inode
566 i_size_write(&inode->vfs_inode, end_pos);
571 * this drops all the extents in the cache that intersect the range
572 * [start, end]. Existing extents are split as required.
574 void btrfs_drop_extent_cache(struct btrfs_inode *inode, u64 start, u64 end,
577 struct extent_map *em;
578 struct extent_map *split = NULL;
579 struct extent_map *split2 = NULL;
580 struct extent_map_tree *em_tree = &inode->extent_tree;
581 u64 len = end - start + 1;
589 WARN_ON(end < start);
590 if (end == (u64)-1) {
599 split = alloc_extent_map();
601 split2 = alloc_extent_map();
602 if (!split || !split2)
605 write_lock(&em_tree->lock);
606 em = lookup_extent_mapping(em_tree, start, len);
608 write_unlock(&em_tree->lock);
612 gen = em->generation;
613 if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
614 if (testend && em->start + em->len >= start + len) {
616 write_unlock(&em_tree->lock);
619 start = em->start + em->len;
621 len = start + len - (em->start + em->len);
623 write_unlock(&em_tree->lock);
626 compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
627 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
628 clear_bit(EXTENT_FLAG_LOGGING, &flags);
629 modified = !list_empty(&em->list);
633 if (em->start < start) {
634 split->start = em->start;
635 split->len = start - em->start;
637 if (em->block_start < EXTENT_MAP_LAST_BYTE) {
638 split->orig_start = em->orig_start;
639 split->block_start = em->block_start;
642 split->block_len = em->block_len;
644 split->block_len = split->len;
645 split->orig_block_len = max(split->block_len,
647 split->ram_bytes = em->ram_bytes;
649 split->orig_start = split->start;
650 split->block_len = 0;
651 split->block_start = em->block_start;
652 split->orig_block_len = 0;
653 split->ram_bytes = split->len;
656 split->generation = gen;
657 split->flags = flags;
658 split->compress_type = em->compress_type;
659 replace_extent_mapping(em_tree, em, split, modified);
660 free_extent_map(split);
664 if (testend && em->start + em->len > start + len) {
665 u64 diff = start + len - em->start;
667 split->start = start + len;
668 split->len = em->start + em->len - (start + len);
669 split->flags = flags;
670 split->compress_type = em->compress_type;
671 split->generation = gen;
673 if (em->block_start < EXTENT_MAP_LAST_BYTE) {
674 split->orig_block_len = max(em->block_len,
677 split->ram_bytes = em->ram_bytes;
679 split->block_len = em->block_len;
680 split->block_start = em->block_start;
681 split->orig_start = em->orig_start;
683 split->block_len = split->len;
684 split->block_start = em->block_start
686 split->orig_start = em->orig_start;
689 split->ram_bytes = split->len;
690 split->orig_start = split->start;
691 split->block_len = 0;
692 split->block_start = em->block_start;
693 split->orig_block_len = 0;
696 if (extent_map_in_tree(em)) {
697 replace_extent_mapping(em_tree, em, split,
700 ret = add_extent_mapping(em_tree, split,
702 ASSERT(ret == 0); /* Logic error */
704 free_extent_map(split);
708 if (extent_map_in_tree(em))
709 remove_extent_mapping(em_tree, em);
710 write_unlock(&em_tree->lock);
714 /* once for the tree*/
718 free_extent_map(split);
720 free_extent_map(split2);
724 * this is very complex, but the basic idea is to drop all extents
725 * in the range start - end. hint_block is filled in with a block number
726 * that would be a good hint to the block allocator for this file.
728 * If an extent intersects the range but is not entirely inside the range
729 * it is either truncated or split. Anything entirely inside the range
730 * is deleted from the tree.
732 int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
733 struct btrfs_root *root, struct btrfs_inode *inode,
734 struct btrfs_path *path, u64 start, u64 end,
735 u64 *drop_end, int drop_cache,
737 u32 extent_item_size,
740 struct btrfs_fs_info *fs_info = root->fs_info;
741 struct extent_buffer *leaf;
742 struct btrfs_file_extent_item *fi;
743 struct btrfs_ref ref = { 0 };
744 struct btrfs_key key;
745 struct btrfs_key new_key;
746 struct inode *vfs_inode = &inode->vfs_inode;
747 u64 ino = btrfs_ino(inode);
748 u64 search_start = start;
751 u64 extent_offset = 0;
753 u64 last_end = start;
759 int modify_tree = -1;
762 int leafs_visited = 0;
765 btrfs_drop_extent_cache(inode, start, end - 1, 0);
767 if (start >= inode->disk_i_size && !replace_extent)
770 update_refs = (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) ||
771 root == fs_info->tree_root);
774 ret = btrfs_lookup_file_extent(trans, root, path, ino,
775 search_start, modify_tree);
778 if (ret > 0 && path->slots[0] > 0 && search_start == start) {
779 leaf = path->nodes[0];
780 btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
781 if (key.objectid == ino &&
782 key.type == BTRFS_EXTENT_DATA_KEY)
788 leaf = path->nodes[0];
789 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
791 ret = btrfs_next_leaf(root, path);
799 leaf = path->nodes[0];
803 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
805 if (key.objectid > ino)
807 if (WARN_ON_ONCE(key.objectid < ino) ||
808 key.type < BTRFS_EXTENT_DATA_KEY) {
813 if (key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
816 fi = btrfs_item_ptr(leaf, path->slots[0],
817 struct btrfs_file_extent_item);
818 extent_type = btrfs_file_extent_type(leaf, fi);
820 if (extent_type == BTRFS_FILE_EXTENT_REG ||
821 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
822 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
823 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
824 extent_offset = btrfs_file_extent_offset(leaf, fi);
825 extent_end = key.offset +
826 btrfs_file_extent_num_bytes(leaf, fi);
827 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
828 extent_end = key.offset +
829 btrfs_file_extent_ram_bytes(leaf, fi);
836 * Don't skip extent items representing 0 byte lengths. They
837 * used to be created (bug) if while punching holes we hit
838 * -ENOSPC condition. So if we find one here, just ensure we
839 * delete it, otherwise we would insert a new file extent item
840 * with the same key (offset) as that 0 bytes length file
841 * extent item in the call to setup_items_for_insert() later
844 if (extent_end == key.offset && extent_end >= search_start) {
845 last_end = extent_end;
846 goto delete_extent_item;
849 if (extent_end <= search_start) {
855 search_start = max(key.offset, start);
856 if (recow || !modify_tree) {
858 btrfs_release_path(path);
863 * | - range to drop - |
864 * | -------- extent -------- |
866 if (start > key.offset && end < extent_end) {
868 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
873 memcpy(&new_key, &key, sizeof(new_key));
874 new_key.offset = start;
875 ret = btrfs_duplicate_item(trans, root, path,
877 if (ret == -EAGAIN) {
878 btrfs_release_path(path);
884 leaf = path->nodes[0];
885 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
886 struct btrfs_file_extent_item);
887 btrfs_set_file_extent_num_bytes(leaf, fi,
890 fi = btrfs_item_ptr(leaf, path->slots[0],
891 struct btrfs_file_extent_item);
893 extent_offset += start - key.offset;
894 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
895 btrfs_set_file_extent_num_bytes(leaf, fi,
897 btrfs_mark_buffer_dirty(leaf);
899 if (update_refs && disk_bytenr > 0) {
900 btrfs_init_generic_ref(&ref,
901 BTRFS_ADD_DELAYED_REF,
902 disk_bytenr, num_bytes, 0);
903 btrfs_init_data_ref(&ref,
904 root->root_key.objectid,
906 start - extent_offset);
907 ret = btrfs_inc_extent_ref(trans, &ref);
908 BUG_ON(ret); /* -ENOMEM */
913 * From here on out we will have actually dropped something, so
914 * last_end can be updated.
916 last_end = extent_end;
919 * | ---- range to drop ----- |
920 * | -------- extent -------- |
922 if (start <= key.offset && end < extent_end) {
923 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
928 memcpy(&new_key, &key, sizeof(new_key));
929 new_key.offset = end;
930 btrfs_set_item_key_safe(fs_info, path, &new_key);
932 extent_offset += end - key.offset;
933 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
934 btrfs_set_file_extent_num_bytes(leaf, fi,
936 btrfs_mark_buffer_dirty(leaf);
937 if (update_refs && disk_bytenr > 0)
938 inode_sub_bytes(vfs_inode, end - key.offset);
942 search_start = extent_end;
944 * | ---- range to drop ----- |
945 * | -------- extent -------- |
947 if (start > key.offset && end >= extent_end) {
949 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
954 btrfs_set_file_extent_num_bytes(leaf, fi,
956 btrfs_mark_buffer_dirty(leaf);
957 if (update_refs && disk_bytenr > 0)
958 inode_sub_bytes(vfs_inode, extent_end - start);
959 if (end == extent_end)
967 * | ---- range to drop ----- |
968 * | ------ extent ------ |
970 if (start <= key.offset && end >= extent_end) {
973 del_slot = path->slots[0];
976 BUG_ON(del_slot + del_nr != path->slots[0]);
981 extent_type == BTRFS_FILE_EXTENT_INLINE) {
982 inode_sub_bytes(vfs_inode,
983 extent_end - key.offset);
984 extent_end = ALIGN(extent_end,
985 fs_info->sectorsize);
986 } else if (update_refs && disk_bytenr > 0) {
987 btrfs_init_generic_ref(&ref,
988 BTRFS_DROP_DELAYED_REF,
989 disk_bytenr, num_bytes, 0);
990 btrfs_init_data_ref(&ref,
991 root->root_key.objectid,
993 key.offset - extent_offset);
994 ret = btrfs_free_extent(trans, &ref);
995 BUG_ON(ret); /* -ENOMEM */
996 inode_sub_bytes(vfs_inode,
997 extent_end - key.offset);
1000 if (end == extent_end)
1003 if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) {
1008 ret = btrfs_del_items(trans, root, path, del_slot,
1011 btrfs_abort_transaction(trans, ret);
1018 btrfs_release_path(path);
1025 if (!ret && del_nr > 0) {
1027 * Set path->slots[0] to first slot, so that after the delete
1028 * if items are move off from our leaf to its immediate left or
1029 * right neighbor leafs, we end up with a correct and adjusted
1030 * path->slots[0] for our insertion (if replace_extent != 0).
1032 path->slots[0] = del_slot;
1033 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
1035 btrfs_abort_transaction(trans, ret);
1038 leaf = path->nodes[0];
1040 * If btrfs_del_items() was called, it might have deleted a leaf, in
1041 * which case it unlocked our path, so check path->locks[0] matches a
1044 if (!ret && replace_extent && leafs_visited == 1 &&
1045 (path->locks[0] == BTRFS_WRITE_LOCK_BLOCKING ||
1046 path->locks[0] == BTRFS_WRITE_LOCK) &&
1047 btrfs_leaf_free_space(leaf) >=
1048 sizeof(struct btrfs_item) + extent_item_size) {
1051 key.type = BTRFS_EXTENT_DATA_KEY;
1053 if (!del_nr && path->slots[0] < btrfs_header_nritems(leaf)) {
1054 struct btrfs_key slot_key;
1056 btrfs_item_key_to_cpu(leaf, &slot_key, path->slots[0]);
1057 if (btrfs_comp_cpu_keys(&key, &slot_key) > 0)
1060 setup_items_for_insert(root, path, &key,
1063 sizeof(struct btrfs_item) +
1064 extent_item_size, 1);
1068 if (!replace_extent || !(*key_inserted))
1069 btrfs_release_path(path);
1071 *drop_end = found ? min(end, last_end) : end;
1075 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
1076 struct btrfs_root *root, struct inode *inode, u64 start,
1077 u64 end, int drop_cache)
1079 struct btrfs_path *path;
1082 path = btrfs_alloc_path();
1085 ret = __btrfs_drop_extents(trans, root, BTRFS_I(inode), path, start,
1086 end, NULL, drop_cache, 0, 0, NULL);
1087 btrfs_free_path(path);
1091 static int extent_mergeable(struct extent_buffer *leaf, int slot,
1092 u64 objectid, u64 bytenr, u64 orig_offset,
1093 u64 *start, u64 *end)
1095 struct btrfs_file_extent_item *fi;
1096 struct btrfs_key key;
1099 if (slot < 0 || slot >= btrfs_header_nritems(leaf))
1102 btrfs_item_key_to_cpu(leaf, &key, slot);
1103 if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
1106 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
1107 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG ||
1108 btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr ||
1109 btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset ||
1110 btrfs_file_extent_compression(leaf, fi) ||
1111 btrfs_file_extent_encryption(leaf, fi) ||
1112 btrfs_file_extent_other_encoding(leaf, fi))
1115 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
1116 if ((*start && *start != key.offset) || (*end && *end != extent_end))
1119 *start = key.offset;
1125 * Mark extent in the range start - end as written.
1127 * This changes extent type from 'pre-allocated' to 'regular'. If only
1128 * part of extent is marked as written, the extent will be split into
1131 int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
1132 struct btrfs_inode *inode, u64 start, u64 end)
1134 struct btrfs_fs_info *fs_info = trans->fs_info;
1135 struct btrfs_root *root = inode->root;
1136 struct extent_buffer *leaf;
1137 struct btrfs_path *path;
1138 struct btrfs_file_extent_item *fi;
1139 struct btrfs_ref ref = { 0 };
1140 struct btrfs_key key;
1141 struct btrfs_key new_key;
1153 u64 ino = btrfs_ino(inode);
1155 path = btrfs_alloc_path();
1162 key.type = BTRFS_EXTENT_DATA_KEY;
1165 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1168 if (ret > 0 && path->slots[0] > 0)
1171 leaf = path->nodes[0];
1172 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1173 if (key.objectid != ino ||
1174 key.type != BTRFS_EXTENT_DATA_KEY) {
1176 btrfs_abort_transaction(trans, ret);
1179 fi = btrfs_item_ptr(leaf, path->slots[0],
1180 struct btrfs_file_extent_item);
1181 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_PREALLOC) {
1183 btrfs_abort_transaction(trans, ret);
1186 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
1187 if (key.offset > start || extent_end < end) {
1189 btrfs_abort_transaction(trans, ret);
1193 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1194 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
1195 orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi);
1196 memcpy(&new_key, &key, sizeof(new_key));
1198 if (start == key.offset && end < extent_end) {
1201 if (extent_mergeable(leaf, path->slots[0] - 1,
1202 ino, bytenr, orig_offset,
1203 &other_start, &other_end)) {
1204 new_key.offset = end;
1205 btrfs_set_item_key_safe(fs_info, path, &new_key);
1206 fi = btrfs_item_ptr(leaf, path->slots[0],
1207 struct btrfs_file_extent_item);
1208 btrfs_set_file_extent_generation(leaf, fi,
1210 btrfs_set_file_extent_num_bytes(leaf, fi,
1212 btrfs_set_file_extent_offset(leaf, fi,
1214 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
1215 struct btrfs_file_extent_item);
1216 btrfs_set_file_extent_generation(leaf, fi,
1218 btrfs_set_file_extent_num_bytes(leaf, fi,
1220 btrfs_mark_buffer_dirty(leaf);
1225 if (start > key.offset && end == extent_end) {
1228 if (extent_mergeable(leaf, path->slots[0] + 1,
1229 ino, bytenr, orig_offset,
1230 &other_start, &other_end)) {
1231 fi = btrfs_item_ptr(leaf, path->slots[0],
1232 struct btrfs_file_extent_item);
1233 btrfs_set_file_extent_num_bytes(leaf, fi,
1234 start - key.offset);
1235 btrfs_set_file_extent_generation(leaf, fi,
1238 new_key.offset = start;
1239 btrfs_set_item_key_safe(fs_info, path, &new_key);
1241 fi = btrfs_item_ptr(leaf, path->slots[0],
1242 struct btrfs_file_extent_item);
1243 btrfs_set_file_extent_generation(leaf, fi,
1245 btrfs_set_file_extent_num_bytes(leaf, fi,
1247 btrfs_set_file_extent_offset(leaf, fi,
1248 start - orig_offset);
1249 btrfs_mark_buffer_dirty(leaf);
1254 while (start > key.offset || end < extent_end) {
1255 if (key.offset == start)
1258 new_key.offset = split;
1259 ret = btrfs_duplicate_item(trans, root, path, &new_key);
1260 if (ret == -EAGAIN) {
1261 btrfs_release_path(path);
1265 btrfs_abort_transaction(trans, ret);
1269 leaf = path->nodes[0];
1270 fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
1271 struct btrfs_file_extent_item);
1272 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1273 btrfs_set_file_extent_num_bytes(leaf, fi,
1274 split - key.offset);
1276 fi = btrfs_item_ptr(leaf, path->slots[0],
1277 struct btrfs_file_extent_item);
1279 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1280 btrfs_set_file_extent_offset(leaf, fi, split - orig_offset);
1281 btrfs_set_file_extent_num_bytes(leaf, fi,
1282 extent_end - split);
1283 btrfs_mark_buffer_dirty(leaf);
1285 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, bytenr,
1287 btrfs_init_data_ref(&ref, root->root_key.objectid, ino,
1289 ret = btrfs_inc_extent_ref(trans, &ref);
1291 btrfs_abort_transaction(trans, ret);
1295 if (split == start) {
1298 if (start != key.offset) {
1300 btrfs_abort_transaction(trans, ret);
1311 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
1313 btrfs_init_data_ref(&ref, root->root_key.objectid, ino, orig_offset);
1314 if (extent_mergeable(leaf, path->slots[0] + 1,
1315 ino, bytenr, orig_offset,
1316 &other_start, &other_end)) {
1318 btrfs_release_path(path);
1321 extent_end = other_end;
1322 del_slot = path->slots[0] + 1;
1324 ret = btrfs_free_extent(trans, &ref);
1326 btrfs_abort_transaction(trans, ret);
1332 if (extent_mergeable(leaf, path->slots[0] - 1,
1333 ino, bytenr, orig_offset,
1334 &other_start, &other_end)) {
1336 btrfs_release_path(path);
1339 key.offset = other_start;
1340 del_slot = path->slots[0];
1342 ret = btrfs_free_extent(trans, &ref);
1344 btrfs_abort_transaction(trans, ret);
1349 fi = btrfs_item_ptr(leaf, path->slots[0],
1350 struct btrfs_file_extent_item);
1351 btrfs_set_file_extent_type(leaf, fi,
1352 BTRFS_FILE_EXTENT_REG);
1353 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1354 btrfs_mark_buffer_dirty(leaf);
1356 fi = btrfs_item_ptr(leaf, del_slot - 1,
1357 struct btrfs_file_extent_item);
1358 btrfs_set_file_extent_type(leaf, fi,
1359 BTRFS_FILE_EXTENT_REG);
1360 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1361 btrfs_set_file_extent_num_bytes(leaf, fi,
1362 extent_end - key.offset);
1363 btrfs_mark_buffer_dirty(leaf);
1365 ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
1367 btrfs_abort_transaction(trans, ret);
1372 btrfs_free_path(path);
1377 * on error we return an unlocked page and the error value
1378 * on success we return a locked page and 0
1380 static int prepare_uptodate_page(struct inode *inode,
1381 struct page *page, u64 pos,
1382 bool force_uptodate)
1386 if (((pos & (PAGE_SIZE - 1)) || force_uptodate) &&
1387 !PageUptodate(page)) {
1388 ret = btrfs_readpage(NULL, page);
1392 if (!PageUptodate(page)) {
1396 if (page->mapping != inode->i_mapping) {
1405 * this just gets pages into the page cache and locks them down.
1407 static noinline int prepare_pages(struct inode *inode, struct page **pages,
1408 size_t num_pages, loff_t pos,
1409 size_t write_bytes, bool force_uptodate)
1412 unsigned long index = pos >> PAGE_SHIFT;
1413 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1417 for (i = 0; i < num_pages; i++) {
1419 pages[i] = find_or_create_page(inode->i_mapping, index + i,
1420 mask | __GFP_WRITE);
1428 err = prepare_uptodate_page(inode, pages[i], pos,
1430 if (!err && i == num_pages - 1)
1431 err = prepare_uptodate_page(inode, pages[i],
1432 pos + write_bytes, false);
1435 if (err == -EAGAIN) {
1442 wait_on_page_writeback(pages[i]);
1447 while (faili >= 0) {
1448 unlock_page(pages[faili]);
1449 put_page(pages[faili]);
1457 * This function locks the extent and properly waits for data=ordered extents
1458 * to finish before allowing the pages to be modified if need.
1461 * 1 - the extent is locked
1462 * 0 - the extent is not locked, and everything is OK
1463 * -EAGAIN - need re-prepare the pages
1464 * the other < 0 number - Something wrong happens
1467 lock_and_cleanup_extent_if_need(struct btrfs_inode *inode, struct page **pages,
1468 size_t num_pages, loff_t pos,
1470 u64 *lockstart, u64 *lockend,
1471 struct extent_state **cached_state)
1473 struct btrfs_fs_info *fs_info = inode->root->fs_info;
1479 start_pos = round_down(pos, fs_info->sectorsize);
1480 last_pos = round_up(pos + write_bytes, fs_info->sectorsize) - 1;
1482 if (start_pos < inode->vfs_inode.i_size) {
1483 struct btrfs_ordered_extent *ordered;
1485 lock_extent_bits(&inode->io_tree, start_pos, last_pos,
1487 ordered = btrfs_lookup_ordered_range(inode, start_pos,
1488 last_pos - start_pos + 1);
1490 ordered->file_offset + ordered->num_bytes > start_pos &&
1491 ordered->file_offset <= last_pos) {
1492 unlock_extent_cached(&inode->io_tree, start_pos,
1493 last_pos, cached_state);
1494 for (i = 0; i < num_pages; i++) {
1495 unlock_page(pages[i]);
1498 btrfs_start_ordered_extent(&inode->vfs_inode,
1500 btrfs_put_ordered_extent(ordered);
1504 btrfs_put_ordered_extent(ordered);
1506 *lockstart = start_pos;
1507 *lockend = last_pos;
1512 * It's possible the pages are dirty right now, but we don't want
1513 * to clean them yet because copy_from_user may catch a page fault
1514 * and we might have to fall back to one page at a time. If that
1515 * happens, we'll unlock these pages and we'd have a window where
1516 * reclaim could sneak in and drop the once-dirty page on the floor
1517 * without writing it.
1519 * We have the pages locked and the extent range locked, so there's
1520 * no way someone can start IO on any dirty pages in this range.
1522 * We'll call btrfs_dirty_pages() later on, and that will flip around
1523 * delalloc bits and dirty the pages as required.
1525 for (i = 0; i < num_pages; i++) {
1526 set_page_extent_mapped(pages[i]);
1527 WARN_ON(!PageLocked(pages[i]));
1533 static int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
1534 size_t *write_bytes, bool nowait)
1536 struct btrfs_fs_info *fs_info = inode->root->fs_info;
1537 struct btrfs_root *root = inode->root;
1538 u64 lockstart, lockend;
1542 if (!(inode->flags & (BTRFS_INODE_NODATACOW | BTRFS_INODE_PREALLOC)))
1545 if (!nowait && !btrfs_drew_try_write_lock(&root->snapshot_lock))
1548 lockstart = round_down(pos, fs_info->sectorsize);
1549 lockend = round_up(pos + *write_bytes,
1550 fs_info->sectorsize) - 1;
1551 num_bytes = lockend - lockstart + 1;
1554 struct btrfs_ordered_extent *ordered;
1556 if (!try_lock_extent(&inode->io_tree, lockstart, lockend))
1559 ordered = btrfs_lookup_ordered_range(inode, lockstart,
1562 btrfs_put_ordered_extent(ordered);
1567 btrfs_lock_and_flush_ordered_range(inode, lockstart,
1571 ret = can_nocow_extent(&inode->vfs_inode, lockstart, &num_bytes,
1572 NULL, NULL, NULL, false);
1576 btrfs_drew_write_unlock(&root->snapshot_lock);
1578 *write_bytes = min_t(size_t, *write_bytes ,
1579 num_bytes - pos + lockstart);
1582 unlock_extent(&inode->io_tree, lockstart, lockend);
1587 static int check_nocow_nolock(struct btrfs_inode *inode, loff_t pos,
1588 size_t *write_bytes)
1590 return check_can_nocow(inode, pos, write_bytes, true);
1594 * Check if we can do nocow write into the range [@pos, @pos + @write_bytes)
1597 * @write_bytes: The length to write, will be updated to the nocow writeable
1600 * This function will flush ordered extents in the range to ensure proper
1604 * >0 and update @write_bytes if we can do nocow write
1605 * 0 if we can't do nocow write
1606 * -EAGAIN if we can't get the needed lock or there are ordered extents
1607 * for * (nowait == true) case
1608 * <0 if other error happened
1610 * NOTE: Callers need to release the lock by btrfs_check_nocow_unlock().
1612 int btrfs_check_nocow_lock(struct btrfs_inode *inode, loff_t pos,
1613 size_t *write_bytes)
1615 return check_can_nocow(inode, pos, write_bytes, false);
1618 void btrfs_check_nocow_unlock(struct btrfs_inode *inode)
1620 btrfs_drew_write_unlock(&inode->root->snapshot_lock);
1623 static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb,
1626 struct file *file = iocb->ki_filp;
1627 loff_t pos = iocb->ki_pos;
1628 struct inode *inode = file_inode(file);
1629 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1630 struct page **pages = NULL;
1631 struct extent_changeset *data_reserved = NULL;
1632 u64 release_bytes = 0;
1635 size_t num_written = 0;
1638 bool only_release_metadata = false;
1639 bool force_page_uptodate = false;
1641 nrptrs = min(DIV_ROUND_UP(iov_iter_count(i), PAGE_SIZE),
1642 PAGE_SIZE / (sizeof(struct page *)));
1643 nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied);
1644 nrptrs = max(nrptrs, 8);
1645 pages = kmalloc_array(nrptrs, sizeof(struct page *), GFP_KERNEL);
1649 while (iov_iter_count(i) > 0) {
1650 struct extent_state *cached_state = NULL;
1651 size_t offset = offset_in_page(pos);
1652 size_t sector_offset;
1653 size_t write_bytes = min(iov_iter_count(i),
1654 nrptrs * (size_t)PAGE_SIZE -
1656 size_t num_pages = DIV_ROUND_UP(write_bytes + offset,
1658 size_t reserve_bytes;
1661 size_t dirty_sectors;
1665 WARN_ON(num_pages > nrptrs);
1668 * Fault pages before locking them in prepare_pages
1669 * to avoid recursive lock
1671 if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) {
1676 only_release_metadata = false;
1677 sector_offset = pos & (fs_info->sectorsize - 1);
1678 reserve_bytes = round_up(write_bytes + sector_offset,
1679 fs_info->sectorsize);
1681 extent_changeset_release(data_reserved);
1682 ret = btrfs_check_data_free_space(BTRFS_I(inode),
1683 &data_reserved, pos,
1686 if (btrfs_check_nocow_lock(BTRFS_I(inode), pos,
1687 &write_bytes) > 0) {
1689 * For nodata cow case, no need to reserve
1692 only_release_metadata = true;
1694 * our prealloc extent may be smaller than
1695 * write_bytes, so scale down.
1697 num_pages = DIV_ROUND_UP(write_bytes + offset,
1699 reserve_bytes = round_up(write_bytes +
1701 fs_info->sectorsize);
1707 WARN_ON(reserve_bytes == 0);
1708 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode),
1711 if (!only_release_metadata)
1712 btrfs_free_reserved_data_space(BTRFS_I(inode),
1716 btrfs_check_nocow_unlock(BTRFS_I(inode));
1720 release_bytes = reserve_bytes;
1723 * This is going to setup the pages array with the number of
1724 * pages we want, so we don't really need to worry about the
1725 * contents of pages from loop to loop
1727 ret = prepare_pages(inode, pages, num_pages,
1729 force_page_uptodate);
1731 btrfs_delalloc_release_extents(BTRFS_I(inode),
1736 extents_locked = lock_and_cleanup_extent_if_need(
1737 BTRFS_I(inode), pages,
1738 num_pages, pos, write_bytes, &lockstart,
1739 &lockend, &cached_state);
1740 if (extents_locked < 0) {
1741 if (extents_locked == -EAGAIN)
1743 btrfs_delalloc_release_extents(BTRFS_I(inode),
1745 ret = extents_locked;
1749 copied = btrfs_copy_from_user(pos, write_bytes, pages, i);
1751 num_sectors = BTRFS_BYTES_TO_BLKS(fs_info, reserve_bytes);
1752 dirty_sectors = round_up(copied + sector_offset,
1753 fs_info->sectorsize);
1754 dirty_sectors = BTRFS_BYTES_TO_BLKS(fs_info, dirty_sectors);
1757 * if we have trouble faulting in the pages, fall
1758 * back to one page at a time
1760 if (copied < write_bytes)
1764 force_page_uptodate = true;
1768 force_page_uptodate = false;
1769 dirty_pages = DIV_ROUND_UP(copied + offset,
1773 if (num_sectors > dirty_sectors) {
1774 /* release everything except the sectors we dirtied */
1775 release_bytes -= dirty_sectors <<
1776 fs_info->sb->s_blocksize_bits;
1777 if (only_release_metadata) {
1778 btrfs_delalloc_release_metadata(BTRFS_I(inode),
1779 release_bytes, true);
1783 __pos = round_down(pos,
1784 fs_info->sectorsize) +
1785 (dirty_pages << PAGE_SHIFT);
1786 btrfs_delalloc_release_space(BTRFS_I(inode),
1787 data_reserved, __pos,
1788 release_bytes, true);
1792 release_bytes = round_up(copied + sector_offset,
1793 fs_info->sectorsize);
1796 ret = btrfs_dirty_pages(BTRFS_I(inode), pages,
1797 dirty_pages, pos, copied,
1801 * If we have not locked the extent range, because the range's
1802 * start offset is >= i_size, we might still have a non-NULL
1803 * cached extent state, acquired while marking the extent range
1804 * as delalloc through btrfs_dirty_pages(). Therefore free any
1805 * possible cached extent state to avoid a memory leak.
1808 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1809 lockstart, lockend, &cached_state);
1811 free_extent_state(cached_state);
1813 btrfs_delalloc_release_extents(BTRFS_I(inode), reserve_bytes);
1815 btrfs_drop_pages(pages, num_pages);
1820 if (only_release_metadata)
1821 btrfs_check_nocow_unlock(BTRFS_I(inode));
1823 if (only_release_metadata && copied > 0) {
1824 lockstart = round_down(pos,
1825 fs_info->sectorsize);
1826 lockend = round_up(pos + copied,
1827 fs_info->sectorsize) - 1;
1829 set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
1830 lockend, EXTENT_NORESERVE, NULL,
1834 btrfs_drop_pages(pages, num_pages);
1838 balance_dirty_pages_ratelimited(inode->i_mapping);
1841 num_written += copied;
1846 if (release_bytes) {
1847 if (only_release_metadata) {
1848 btrfs_check_nocow_unlock(BTRFS_I(inode));
1849 btrfs_delalloc_release_metadata(BTRFS_I(inode),
1850 release_bytes, true);
1852 btrfs_delalloc_release_space(BTRFS_I(inode),
1854 round_down(pos, fs_info->sectorsize),
1855 release_bytes, true);
1859 extent_changeset_free(data_reserved);
1860 return num_written ? num_written : ret;
1863 static ssize_t __btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
1865 struct file *file = iocb->ki_filp;
1866 struct inode *inode = file_inode(file);
1869 ssize_t written_buffered;
1873 written = btrfs_direct_IO(iocb, from);
1875 if (written < 0 || !iov_iter_count(from))
1879 written_buffered = btrfs_buffered_write(iocb, from);
1880 if (written_buffered < 0) {
1881 err = written_buffered;
1885 * Ensure all data is persisted. We want the next direct IO read to be
1886 * able to read what was just written.
1888 endbyte = pos + written_buffered - 1;
1889 err = btrfs_fdatawrite_range(inode, pos, endbyte);
1892 err = filemap_fdatawait_range(inode->i_mapping, pos, endbyte);
1895 written += written_buffered;
1896 iocb->ki_pos = pos + written_buffered;
1897 invalidate_mapping_pages(file->f_mapping, pos >> PAGE_SHIFT,
1898 endbyte >> PAGE_SHIFT);
1900 return written ? written : err;
1903 static void update_time_for_write(struct inode *inode)
1905 struct timespec64 now;
1907 if (IS_NOCMTIME(inode))
1910 now = current_time(inode);
1911 if (!timespec64_equal(&inode->i_mtime, &now))
1912 inode->i_mtime = now;
1914 if (!timespec64_equal(&inode->i_ctime, &now))
1915 inode->i_ctime = now;
1917 if (IS_I_VERSION(inode))
1918 inode_inc_iversion(inode);
1921 static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
1922 struct iov_iter *from)
1924 struct file *file = iocb->ki_filp;
1925 struct inode *inode = file_inode(file);
1926 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1927 struct btrfs_root *root = BTRFS_I(inode)->root;
1930 ssize_t num_written = 0;
1931 const bool sync = iocb->ki_flags & IOCB_DSYNC;
1938 if (!(iocb->ki_flags & IOCB_DIRECT) &&
1939 (iocb->ki_flags & IOCB_NOWAIT))
1942 if (iocb->ki_flags & IOCB_NOWAIT) {
1943 if (!inode_trylock(inode))
1949 err = generic_write_checks(iocb, from);
1951 inode_unlock(inode);
1956 count = iov_iter_count(from);
1957 if (iocb->ki_flags & IOCB_NOWAIT) {
1958 size_t nocow_bytes = count;
1961 * We will allocate space in case nodatacow is not set,
1964 if (check_nocow_nolock(BTRFS_I(inode), pos, &nocow_bytes)
1966 inode_unlock(inode);
1970 * There are holes in the range or parts of the range that must
1971 * be COWed (shared extents, RO block groups, etc), so just bail
1974 if (nocow_bytes < count) {
1975 inode_unlock(inode);
1980 current->backing_dev_info = inode_to_bdi(inode);
1981 err = file_remove_privs(file);
1983 inode_unlock(inode);
1988 * If BTRFS flips readonly due to some impossible error
1989 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1990 * although we have opened a file as writable, we have
1991 * to stop this write operation to ensure FS consistency.
1993 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
1994 inode_unlock(inode);
2000 * We reserve space for updating the inode when we reserve space for the
2001 * extent we are going to write, so we will enospc out there. We don't
2002 * need to start yet another transaction to update the inode as we will
2003 * update the inode when we finish writing whatever data we write.
2005 update_time_for_write(inode);
2007 start_pos = round_down(pos, fs_info->sectorsize);
2008 oldsize = i_size_read(inode);
2009 if (start_pos > oldsize) {
2010 /* Expand hole size to cover write data, preventing empty gap */
2011 end_pos = round_up(pos + count,
2012 fs_info->sectorsize);
2013 err = btrfs_cont_expand(inode, oldsize, end_pos);
2015 inode_unlock(inode);
2018 if (start_pos > round_up(oldsize, fs_info->sectorsize))
2023 atomic_inc(&BTRFS_I(inode)->sync_writers);
2025 if (iocb->ki_flags & IOCB_DIRECT) {
2027 * 1. We must always clear IOCB_DSYNC in order to not deadlock
2028 * in iomap, as it calls generic_write_sync() in this case.
2029 * 2. If we are async, we can call iomap_dio_complete() either
2032 * 2.1. A worker thread from the last bio completed. In this
2033 * case we need to mark the btrfs_dio_data that it is
2034 * async in order to call generic_write_sync() properly.
2035 * This is handled by setting BTRFS_DIO_SYNC_STUB in the
2036 * current->journal_info.
2037 * 2.2 The submitter context, because all IO completed
2038 * before we exited iomap_dio_rw(). In this case we can
2039 * just re-set the IOCB_DSYNC on the iocb and we'll do
2040 * the sync below. If our ->end_io() gets called and
2041 * current->journal_info is set, then we know we're in
2042 * our current context and we will clear
2043 * current->journal_info to indicate that we need to
2047 ASSERT(current->journal_info == NULL);
2048 iocb->ki_flags &= ~IOCB_DSYNC;
2049 current->journal_info = BTRFS_DIO_SYNC_STUB;
2051 num_written = __btrfs_direct_write(iocb, from);
2054 * As stated above, we cleared journal_info, so we need to do
2055 * the sync ourselves.
2057 if (sync && current->journal_info == NULL)
2058 iocb->ki_flags |= IOCB_DSYNC;
2059 current->journal_info = NULL;
2061 num_written = btrfs_buffered_write(iocb, from);
2062 if (num_written > 0)
2063 iocb->ki_pos = pos + num_written;
2065 pagecache_isize_extended(inode, oldsize,
2066 i_size_read(inode));
2069 inode_unlock(inode);
2072 * We also have to set last_sub_trans to the current log transid,
2073 * otherwise subsequent syncs to a file that's been synced in this
2074 * transaction will appear to have already occurred.
2076 spin_lock(&BTRFS_I(inode)->lock);
2077 BTRFS_I(inode)->last_sub_trans = root->log_transid;
2078 spin_unlock(&BTRFS_I(inode)->lock);
2079 if (num_written > 0)
2080 num_written = generic_write_sync(iocb, num_written);
2083 atomic_dec(&BTRFS_I(inode)->sync_writers);
2085 current->backing_dev_info = NULL;
2086 return num_written ? num_written : err;
2089 int btrfs_release_file(struct inode *inode, struct file *filp)
2091 struct btrfs_file_private *private = filp->private_data;
2093 if (private && private->filldir_buf)
2094 kfree(private->filldir_buf);
2096 filp->private_data = NULL;
2099 * ordered_data_close is set by setattr when we are about to truncate
2100 * a file from a non-zero size to a zero size. This tries to
2101 * flush down new bytes that may have been written if the
2102 * application were using truncate to replace a file in place.
2104 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
2105 &BTRFS_I(inode)->runtime_flags))
2106 filemap_flush(inode->i_mapping);
2110 static int start_ordered_ops(struct inode *inode, loff_t start, loff_t end)
2113 struct blk_plug plug;
2116 * This is only called in fsync, which would do synchronous writes, so
2117 * a plug can merge adjacent IOs as much as possible. Esp. in case of
2118 * multiple disks using raid profile, a large IO can be split to
2119 * several segments of stripe length (currently 64K).
2121 blk_start_plug(&plug);
2122 atomic_inc(&BTRFS_I(inode)->sync_writers);
2123 ret = btrfs_fdatawrite_range(inode, start, end);
2124 atomic_dec(&BTRFS_I(inode)->sync_writers);
2125 blk_finish_plug(&plug);
2131 * fsync call for both files and directories. This logs the inode into
2132 * the tree log instead of forcing full commits whenever possible.
2134 * It needs to call filemap_fdatawait so that all ordered extent updates are
2135 * in the metadata btree are up to date for copying to the log.
2137 * It drops the inode mutex before doing the tree log commit. This is an
2138 * important optimization for directories because holding the mutex prevents
2139 * new operations on the dir while we write to disk.
2141 int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
2143 struct dentry *dentry = file_dentry(file);
2144 struct inode *inode = d_inode(dentry);
2145 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2146 struct btrfs_root *root = BTRFS_I(inode)->root;
2147 struct btrfs_trans_handle *trans;
2148 struct btrfs_log_ctx ctx;
2153 trace_btrfs_sync_file(file, datasync);
2155 btrfs_init_log_ctx(&ctx, inode);
2158 * Always set the range to a full range, otherwise we can get into
2159 * several problems, from missing file extent items to represent holes
2160 * when not using the NO_HOLES feature, to log tree corruption due to
2161 * races between hole detection during logging and completion of ordered
2162 * extents outside the range, to missing checksums due to ordered extents
2163 * for which we flushed only a subset of their pages.
2167 len = (u64)LLONG_MAX + 1;
2170 * We write the dirty pages in the range and wait until they complete
2171 * out of the ->i_mutex. If so, we can flush the dirty pages by
2172 * multi-task, and make the performance up. See
2173 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
2175 ret = start_ordered_ops(inode, start, end);
2182 * We take the dio_sem here because the tree log stuff can race with
2183 * lockless dio writes and get an extent map logged for an extent we
2184 * never waited on. We need it this high up for lockdep reasons.
2186 down_write(&BTRFS_I(inode)->dio_sem);
2188 atomic_inc(&root->log_batch);
2191 * Always check for the full sync flag while holding the inode's lock,
2192 * to avoid races with other tasks. The flag must be either set all the
2193 * time during logging or always off all the time while logging.
2195 full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2196 &BTRFS_I(inode)->runtime_flags);
2199 * Before we acquired the inode's lock, someone may have dirtied more
2200 * pages in the target range. We need to make sure that writeback for
2201 * any such pages does not start while we are logging the inode, because
2202 * if it does, any of the following might happen when we are not doing a
2205 * 1) We log an extent after its writeback finishes but before its
2206 * checksums are added to the csum tree, leading to -EIO errors
2207 * when attempting to read the extent after a log replay.
2209 * 2) We can end up logging an extent before its writeback finishes.
2210 * Therefore after the log replay we will have a file extent item
2211 * pointing to an unwritten extent (and no data checksums as well).
2213 * So trigger writeback for any eventual new dirty pages and then we
2214 * wait for all ordered extents to complete below.
2216 ret = start_ordered_ops(inode, start, end);
2218 up_write(&BTRFS_I(inode)->dio_sem);
2219 inode_unlock(inode);
2224 * We have to do this here to avoid the priority inversion of waiting on
2225 * IO of a lower priority task while holding a transaction open.
2227 * For a full fsync we wait for the ordered extents to complete while
2228 * for a fast fsync we wait just for writeback to complete, and then
2229 * attach the ordered extents to the transaction so that a transaction
2230 * commit waits for their completion, to avoid data loss if we fsync,
2231 * the current transaction commits before the ordered extents complete
2232 * and a power failure happens right after that.
2235 ret = btrfs_wait_ordered_range(inode, start, len);
2238 * Get our ordered extents as soon as possible to avoid doing
2239 * checksum lookups in the csum tree, and use instead the
2240 * checksums attached to the ordered extents.
2242 btrfs_get_ordered_extents_for_logging(BTRFS_I(inode),
2243 &ctx.ordered_extents);
2244 ret = filemap_fdatawait_range(inode->i_mapping, start, end);
2248 goto out_release_extents;
2250 atomic_inc(&root->log_batch);
2253 * If we are doing a fast fsync we can not bail out if the inode's
2254 * last_trans is <= then the last committed transaction, because we only
2255 * update the last_trans of the inode during ordered extent completion,
2256 * and for a fast fsync we don't wait for that, we only wait for the
2257 * writeback to complete.
2260 if (btrfs_inode_in_log(BTRFS_I(inode), fs_info->generation) ||
2261 (BTRFS_I(inode)->last_trans <= fs_info->last_trans_committed &&
2262 (full_sync || list_empty(&ctx.ordered_extents)))) {
2264 * We've had everything committed since the last time we were
2265 * modified so clear this flag in case it was set for whatever
2266 * reason, it's no longer relevant.
2268 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2269 &BTRFS_I(inode)->runtime_flags);
2271 * An ordered extent might have started before and completed
2272 * already with io errors, in which case the inode was not
2273 * updated and we end up here. So check the inode's mapping
2274 * for any errors that might have happened since we last
2275 * checked called fsync.
2277 ret = filemap_check_wb_err(inode->i_mapping, file->f_wb_err);
2278 goto out_release_extents;
2282 * We use start here because we will need to wait on the IO to complete
2283 * in btrfs_sync_log, which could require joining a transaction (for
2284 * example checking cross references in the nocow path). If we use join
2285 * here we could get into a situation where we're waiting on IO to
2286 * happen that is blocked on a transaction trying to commit. With start
2287 * we inc the extwriter counter, so we wait for all extwriters to exit
2288 * before we start blocking joiners. This comment is to keep somebody
2289 * from thinking they are super smart and changing this to
2290 * btrfs_join_transaction *cough*Josef*cough*.
2292 trans = btrfs_start_transaction(root, 0);
2293 if (IS_ERR(trans)) {
2294 ret = PTR_ERR(trans);
2295 goto out_release_extents;
2298 ret = btrfs_log_dentry_safe(trans, dentry, &ctx);
2299 btrfs_release_log_ctx_extents(&ctx);
2301 /* Fallthrough and commit/free transaction. */
2305 /* we've logged all the items and now have a consistent
2306 * version of the file in the log. It is possible that
2307 * someone will come in and modify the file, but that's
2308 * fine because the log is consistent on disk, and we
2309 * have references to all of the file's extents
2311 * It is possible that someone will come in and log the
2312 * file again, but that will end up using the synchronization
2313 * inside btrfs_sync_log to keep things safe.
2315 up_write(&BTRFS_I(inode)->dio_sem);
2316 inode_unlock(inode);
2318 if (ret != BTRFS_NO_LOG_SYNC) {
2320 ret = btrfs_sync_log(trans, root, &ctx);
2322 ret = btrfs_end_transaction(trans);
2327 ret = btrfs_wait_ordered_range(inode, start, len);
2329 btrfs_end_transaction(trans);
2333 ret = btrfs_commit_transaction(trans);
2335 ret = btrfs_end_transaction(trans);
2338 ASSERT(list_empty(&ctx.list));
2339 err = file_check_and_advance_wb_err(file);
2342 return ret > 0 ? -EIO : ret;
2344 out_release_extents:
2345 btrfs_release_log_ctx_extents(&ctx);
2346 up_write(&BTRFS_I(inode)->dio_sem);
2347 inode_unlock(inode);
2351 static const struct vm_operations_struct btrfs_file_vm_ops = {
2352 .fault = filemap_fault,
2353 .map_pages = filemap_map_pages,
2354 .page_mkwrite = btrfs_page_mkwrite,
2357 static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
2359 struct address_space *mapping = filp->f_mapping;
2361 if (!mapping->a_ops->readpage)
2364 file_accessed(filp);
2365 vma->vm_ops = &btrfs_file_vm_ops;
2370 static int hole_mergeable(struct btrfs_inode *inode, struct extent_buffer *leaf,
2371 int slot, u64 start, u64 end)
2373 struct btrfs_file_extent_item *fi;
2374 struct btrfs_key key;
2376 if (slot < 0 || slot >= btrfs_header_nritems(leaf))
2379 btrfs_item_key_to_cpu(leaf, &key, slot);
2380 if (key.objectid != btrfs_ino(inode) ||
2381 key.type != BTRFS_EXTENT_DATA_KEY)
2384 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
2386 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2389 if (btrfs_file_extent_disk_bytenr(leaf, fi))
2392 if (key.offset == end)
2394 if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start)
2399 static int fill_holes(struct btrfs_trans_handle *trans,
2400 struct btrfs_inode *inode,
2401 struct btrfs_path *path, u64 offset, u64 end)
2403 struct btrfs_fs_info *fs_info = trans->fs_info;
2404 struct btrfs_root *root = inode->root;
2405 struct extent_buffer *leaf;
2406 struct btrfs_file_extent_item *fi;
2407 struct extent_map *hole_em;
2408 struct extent_map_tree *em_tree = &inode->extent_tree;
2409 struct btrfs_key key;
2412 if (btrfs_fs_incompat(fs_info, NO_HOLES))
2415 key.objectid = btrfs_ino(inode);
2416 key.type = BTRFS_EXTENT_DATA_KEY;
2417 key.offset = offset;
2419 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2422 * We should have dropped this offset, so if we find it then
2423 * something has gone horribly wrong.
2430 leaf = path->nodes[0];
2431 if (hole_mergeable(inode, leaf, path->slots[0] - 1, offset, end)) {
2435 fi = btrfs_item_ptr(leaf, path->slots[0],
2436 struct btrfs_file_extent_item);
2437 num_bytes = btrfs_file_extent_num_bytes(leaf, fi) +
2439 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2440 btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
2441 btrfs_set_file_extent_offset(leaf, fi, 0);
2442 btrfs_mark_buffer_dirty(leaf);
2446 if (hole_mergeable(inode, leaf, path->slots[0], offset, end)) {
2449 key.offset = offset;
2450 btrfs_set_item_key_safe(fs_info, path, &key);
2451 fi = btrfs_item_ptr(leaf, path->slots[0],
2452 struct btrfs_file_extent_item);
2453 num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end -
2455 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2456 btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
2457 btrfs_set_file_extent_offset(leaf, fi, 0);
2458 btrfs_mark_buffer_dirty(leaf);
2461 btrfs_release_path(path);
2463 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode),
2464 offset, 0, 0, end - offset, 0, end - offset, 0, 0, 0);
2469 btrfs_release_path(path);
2471 hole_em = alloc_extent_map();
2473 btrfs_drop_extent_cache(inode, offset, end - 1, 0);
2474 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
2476 hole_em->start = offset;
2477 hole_em->len = end - offset;
2478 hole_em->ram_bytes = hole_em->len;
2479 hole_em->orig_start = offset;
2481 hole_em->block_start = EXTENT_MAP_HOLE;
2482 hole_em->block_len = 0;
2483 hole_em->orig_block_len = 0;
2484 hole_em->compress_type = BTRFS_COMPRESS_NONE;
2485 hole_em->generation = trans->transid;
2488 btrfs_drop_extent_cache(inode, offset, end - 1, 0);
2489 write_lock(&em_tree->lock);
2490 ret = add_extent_mapping(em_tree, hole_em, 1);
2491 write_unlock(&em_tree->lock);
2492 } while (ret == -EEXIST);
2493 free_extent_map(hole_em);
2495 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2496 &inode->runtime_flags);
2503 * Find a hole extent on given inode and change start/len to the end of hole
2504 * extent.(hole/vacuum extent whose em->start <= start &&
2505 * em->start + em->len > start)
2506 * When a hole extent is found, return 1 and modify start/len.
2508 static int find_first_non_hole(struct inode *inode, u64 *start, u64 *len)
2510 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2511 struct extent_map *em;
2514 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0,
2515 round_down(*start, fs_info->sectorsize),
2516 round_up(*len, fs_info->sectorsize));
2520 /* Hole or vacuum extent(only exists in no-hole mode) */
2521 if (em->block_start == EXTENT_MAP_HOLE) {
2523 *len = em->start + em->len > *start + *len ?
2524 0 : *start + *len - em->start - em->len;
2525 *start = em->start + em->len;
2527 free_extent_map(em);
2531 static int btrfs_punch_hole_lock_range(struct inode *inode,
2532 const u64 lockstart,
2534 struct extent_state **cached_state)
2537 struct btrfs_ordered_extent *ordered;
2540 truncate_pagecache_range(inode, lockstart, lockend);
2542 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
2544 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode),
2548 * We need to make sure we have no ordered extents in this range
2549 * and nobody raced in and read a page in this range, if we did
2550 * we need to try again.
2553 (ordered->file_offset + ordered->num_bytes <= lockstart ||
2554 ordered->file_offset > lockend)) &&
2555 !filemap_range_has_page(inode->i_mapping,
2556 lockstart, lockend)) {
2558 btrfs_put_ordered_extent(ordered);
2562 btrfs_put_ordered_extent(ordered);
2563 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
2564 lockend, cached_state);
2565 ret = btrfs_wait_ordered_range(inode, lockstart,
2566 lockend - lockstart + 1);
2573 static int btrfs_insert_clone_extent(struct btrfs_trans_handle *trans,
2574 struct inode *inode,
2575 struct btrfs_path *path,
2576 struct btrfs_clone_extent_info *clone_info,
2577 const u64 clone_len)
2579 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2580 struct btrfs_root *root = BTRFS_I(inode)->root;
2581 struct btrfs_file_extent_item *extent;
2582 struct extent_buffer *leaf;
2583 struct btrfs_key key;
2585 struct btrfs_ref ref = { 0 };
2592 if (clone_info->disk_offset == 0 &&
2593 btrfs_fs_incompat(fs_info, NO_HOLES))
2596 key.objectid = btrfs_ino(BTRFS_I(inode));
2597 key.type = BTRFS_EXTENT_DATA_KEY;
2598 key.offset = clone_info->file_offset;
2599 ret = btrfs_insert_empty_item(trans, root, path, &key,
2600 clone_info->item_size);
2603 leaf = path->nodes[0];
2604 slot = path->slots[0];
2605 write_extent_buffer(leaf, clone_info->extent_buf,
2606 btrfs_item_ptr_offset(leaf, slot),
2607 clone_info->item_size);
2608 extent = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
2609 btrfs_set_file_extent_offset(leaf, extent, clone_info->data_offset);
2610 btrfs_set_file_extent_num_bytes(leaf, extent, clone_len);
2611 btrfs_mark_buffer_dirty(leaf);
2612 btrfs_release_path(path);
2614 ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode),
2615 clone_info->file_offset, clone_len);
2619 /* If it's a hole, nothing more needs to be done. */
2620 if (clone_info->disk_offset == 0)
2623 inode_add_bytes(inode, clone_len);
2624 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF,
2625 clone_info->disk_offset,
2626 clone_info->disk_len, 0);
2627 ref_offset = clone_info->file_offset - clone_info->data_offset;
2628 btrfs_init_data_ref(&ref, root->root_key.objectid,
2629 btrfs_ino(BTRFS_I(inode)), ref_offset);
2630 ret = btrfs_inc_extent_ref(trans, &ref);
2636 * The respective range must have been previously locked, as well as the inode.
2637 * The end offset is inclusive (last byte of the range).
2638 * @clone_info is NULL for fallocate's hole punching and non-NULL for extent
2640 * When cloning, we don't want to end up in a state where we dropped extents
2641 * without inserting a new one, so we must abort the transaction to avoid a
2644 int btrfs_punch_hole_range(struct inode *inode, struct btrfs_path *path,
2645 const u64 start, const u64 end,
2646 struct btrfs_clone_extent_info *clone_info,
2647 struct btrfs_trans_handle **trans_out)
2649 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2650 u64 min_size = btrfs_calc_insert_metadata_size(fs_info, 1);
2651 u64 ino_size = round_up(inode->i_size, fs_info->sectorsize);
2652 struct btrfs_root *root = BTRFS_I(inode)->root;
2653 struct btrfs_trans_handle *trans = NULL;
2654 struct btrfs_block_rsv *rsv;
2655 unsigned int rsv_count;
2658 u64 len = end - start;
2664 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
2669 rsv->size = btrfs_calc_insert_metadata_size(fs_info, 1);
2673 * 1 - update the inode
2674 * 1 - removing the extents in the range
2675 * 1 - adding the hole extent if no_holes isn't set or if we are cloning
2678 if (!btrfs_fs_incompat(fs_info, NO_HOLES) || clone_info)
2683 trans = btrfs_start_transaction(root, rsv_count);
2684 if (IS_ERR(trans)) {
2685 ret = PTR_ERR(trans);
2690 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv,
2693 trans->block_rsv = rsv;
2696 while (cur_offset < end) {
2697 ret = __btrfs_drop_extents(trans, root, BTRFS_I(inode), path,
2698 cur_offset, end + 1, &drop_end,
2700 if (ret != -ENOSPC) {
2702 * When cloning we want to avoid transaction aborts when
2703 * nothing was done and we are attempting to clone parts
2704 * of inline extents, in such cases -EOPNOTSUPP is
2705 * returned by __btrfs_drop_extents() without having
2706 * changed anything in the file.
2708 if (clone_info && ret && ret != -EOPNOTSUPP)
2709 btrfs_abort_transaction(trans, ret);
2713 trans->block_rsv = &fs_info->trans_block_rsv;
2715 if (!clone_info && cur_offset < drop_end &&
2716 cur_offset < ino_size) {
2717 ret = fill_holes(trans, BTRFS_I(inode), path,
2718 cur_offset, drop_end);
2721 * If we failed then we didn't insert our hole
2722 * entries for the area we dropped, so now the
2723 * fs is corrupted, so we must abort the
2726 btrfs_abort_transaction(trans, ret);
2729 } else if (!clone_info && cur_offset < drop_end) {
2731 * We are past the i_size here, but since we didn't
2732 * insert holes we need to clear the mapped area so we
2733 * know to not set disk_i_size in this area until a new
2734 * file extent is inserted here.
2736 ret = btrfs_inode_clear_file_extent_range(BTRFS_I(inode),
2737 cur_offset, drop_end - cur_offset);
2740 * We couldn't clear our area, so we could
2741 * presumably adjust up and corrupt the fs, so
2744 btrfs_abort_transaction(trans, ret);
2749 if (clone_info && drop_end > clone_info->file_offset) {
2750 u64 clone_len = drop_end - clone_info->file_offset;
2752 ret = btrfs_insert_clone_extent(trans, inode, path,
2753 clone_info, clone_len);
2755 btrfs_abort_transaction(trans, ret);
2758 clone_info->data_len -= clone_len;
2759 clone_info->data_offset += clone_len;
2760 clone_info->file_offset += clone_len;
2763 cur_offset = drop_end;
2765 ret = btrfs_update_inode(trans, root, inode);
2769 btrfs_end_transaction(trans);
2770 btrfs_btree_balance_dirty(fs_info);
2772 trans = btrfs_start_transaction(root, rsv_count);
2773 if (IS_ERR(trans)) {
2774 ret = PTR_ERR(trans);
2779 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv,
2780 rsv, min_size, false);
2781 BUG_ON(ret); /* shouldn't happen */
2782 trans->block_rsv = rsv;
2785 ret = find_first_non_hole(inode, &cur_offset, &len);
2786 if (unlikely(ret < 0))
2796 * If we were cloning, force the next fsync to be a full one since we
2797 * we replaced (or just dropped in the case of cloning holes when
2798 * NO_HOLES is enabled) extents and extent maps.
2799 * This is for the sake of simplicity, and cloning into files larger
2800 * than 16Mb would force the full fsync any way (when
2801 * try_release_extent_mapping() is invoked during page cache truncation.
2804 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
2805 &BTRFS_I(inode)->runtime_flags);
2810 trans->block_rsv = &fs_info->trans_block_rsv;
2812 * If we are using the NO_HOLES feature we might have had already an
2813 * hole that overlaps a part of the region [lockstart, lockend] and
2814 * ends at (or beyond) lockend. Since we have no file extent items to
2815 * represent holes, drop_end can be less than lockend and so we must
2816 * make sure we have an extent map representing the existing hole (the
2817 * call to __btrfs_drop_extents() might have dropped the existing extent
2818 * map representing the existing hole), otherwise the fast fsync path
2819 * will not record the existence of the hole region
2820 * [existing_hole_start, lockend].
2822 if (drop_end <= end)
2825 * Don't insert file hole extent item if it's for a range beyond eof
2826 * (because it's useless) or if it represents a 0 bytes range (when
2827 * cur_offset == drop_end).
2829 if (!clone_info && cur_offset < ino_size && cur_offset < drop_end) {
2830 ret = fill_holes(trans, BTRFS_I(inode), path,
2831 cur_offset, drop_end);
2833 /* Same comment as above. */
2834 btrfs_abort_transaction(trans, ret);
2837 } else if (!clone_info && cur_offset < drop_end) {
2838 /* See the comment in the loop above for the reasoning here. */
2839 ret = btrfs_inode_clear_file_extent_range(BTRFS_I(inode),
2840 cur_offset, drop_end - cur_offset);
2842 btrfs_abort_transaction(trans, ret);
2848 ret = btrfs_insert_clone_extent(trans, inode, path, clone_info,
2849 clone_info->data_len);
2851 btrfs_abort_transaction(trans, ret);
2860 trans->block_rsv = &fs_info->trans_block_rsv;
2862 btrfs_end_transaction(trans);
2866 btrfs_free_block_rsv(fs_info, rsv);
2871 static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
2873 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2874 struct btrfs_root *root = BTRFS_I(inode)->root;
2875 struct extent_state *cached_state = NULL;
2876 struct btrfs_path *path;
2877 struct btrfs_trans_handle *trans = NULL;
2882 u64 orig_start = offset;
2886 bool truncated_block = false;
2887 bool updated_inode = false;
2889 ret = btrfs_wait_ordered_range(inode, offset, len);
2894 ino_size = round_up(inode->i_size, fs_info->sectorsize);
2895 ret = find_first_non_hole(inode, &offset, &len);
2897 goto out_only_mutex;
2899 /* Already in a large hole */
2901 goto out_only_mutex;
2904 lockstart = round_up(offset, btrfs_inode_sectorsize(inode));
2905 lockend = round_down(offset + len,
2906 btrfs_inode_sectorsize(inode)) - 1;
2907 same_block = (BTRFS_BYTES_TO_BLKS(fs_info, offset))
2908 == (BTRFS_BYTES_TO_BLKS(fs_info, offset + len - 1));
2910 * We needn't truncate any block which is beyond the end of the file
2911 * because we are sure there is no data there.
2914 * Only do this if we are in the same block and we aren't doing the
2917 if (same_block && len < fs_info->sectorsize) {
2918 if (offset < ino_size) {
2919 truncated_block = true;
2920 ret = btrfs_truncate_block(inode, offset, len, 0);
2924 goto out_only_mutex;
2927 /* zero back part of the first block */
2928 if (offset < ino_size) {
2929 truncated_block = true;
2930 ret = btrfs_truncate_block(inode, offset, 0, 0);
2932 inode_unlock(inode);
2937 /* Check the aligned pages after the first unaligned page,
2938 * if offset != orig_start, which means the first unaligned page
2939 * including several following pages are already in holes,
2940 * the extra check can be skipped */
2941 if (offset == orig_start) {
2942 /* after truncate page, check hole again */
2943 len = offset + len - lockstart;
2945 ret = find_first_non_hole(inode, &offset, &len);
2947 goto out_only_mutex;
2950 goto out_only_mutex;
2955 /* Check the tail unaligned part is in a hole */
2956 tail_start = lockend + 1;
2957 tail_len = offset + len - tail_start;
2959 ret = find_first_non_hole(inode, &tail_start, &tail_len);
2960 if (unlikely(ret < 0))
2961 goto out_only_mutex;
2963 /* zero the front end of the last page */
2964 if (tail_start + tail_len < ino_size) {
2965 truncated_block = true;
2966 ret = btrfs_truncate_block(inode,
2967 tail_start + tail_len,
2970 goto out_only_mutex;
2975 if (lockend < lockstart) {
2977 goto out_only_mutex;
2980 ret = btrfs_punch_hole_lock_range(inode, lockstart, lockend,
2983 goto out_only_mutex;
2985 path = btrfs_alloc_path();
2991 ret = btrfs_punch_hole_range(inode, path, lockstart, lockend, NULL,
2993 btrfs_free_path(path);
2997 ASSERT(trans != NULL);
2998 inode_inc_iversion(inode);
2999 inode->i_mtime = inode->i_ctime = current_time(inode);
3000 ret = btrfs_update_inode(trans, root, inode);
3001 updated_inode = true;
3002 btrfs_end_transaction(trans);
3003 btrfs_btree_balance_dirty(fs_info);
3005 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
3008 if (!updated_inode && truncated_block && !ret) {
3010 * If we only end up zeroing part of a page, we still need to
3011 * update the inode item, so that all the time fields are
3012 * updated as well as the necessary btrfs inode in memory fields
3013 * for detecting, at fsync time, if the inode isn't yet in the
3014 * log tree or it's there but not up to date.
3016 struct timespec64 now = current_time(inode);
3018 inode_inc_iversion(inode);
3019 inode->i_mtime = now;
3020 inode->i_ctime = now;
3021 trans = btrfs_start_transaction(root, 1);
3022 if (IS_ERR(trans)) {
3023 ret = PTR_ERR(trans);
3027 ret = btrfs_update_inode(trans, root, inode);
3028 ret2 = btrfs_end_transaction(trans);
3033 inode_unlock(inode);
3037 /* Helper structure to record which range is already reserved */
3038 struct falloc_range {
3039 struct list_head list;
3045 * Helper function to add falloc range
3047 * Caller should have locked the larger range of extent containing
3050 static int add_falloc_range(struct list_head *head, u64 start, u64 len)
3052 struct falloc_range *prev = NULL;
3053 struct falloc_range *range = NULL;
3055 if (list_empty(head))
3059 * As fallocate iterate by bytenr order, we only need to check
3062 prev = list_entry(head->prev, struct falloc_range, list);
3063 if (prev->start + prev->len == start) {
3068 range = kmalloc(sizeof(*range), GFP_KERNEL);
3071 range->start = start;
3073 list_add_tail(&range->list, head);
3077 static int btrfs_fallocate_update_isize(struct inode *inode,
3081 struct btrfs_trans_handle *trans;
3082 struct btrfs_root *root = BTRFS_I(inode)->root;
3086 if (mode & FALLOC_FL_KEEP_SIZE || end <= i_size_read(inode))
3089 trans = btrfs_start_transaction(root, 1);
3091 return PTR_ERR(trans);
3093 inode->i_ctime = current_time(inode);
3094 i_size_write(inode, end);
3095 btrfs_inode_safe_disk_i_size_write(inode, 0);
3096 ret = btrfs_update_inode(trans, root, inode);
3097 ret2 = btrfs_end_transaction(trans);
3099 return ret ? ret : ret2;
3103 RANGE_BOUNDARY_WRITTEN_EXTENT,
3104 RANGE_BOUNDARY_PREALLOC_EXTENT,
3105 RANGE_BOUNDARY_HOLE,
3108 static int btrfs_zero_range_check_range_boundary(struct inode *inode,
3111 const u64 sectorsize = btrfs_inode_sectorsize(inode);
3112 struct extent_map *em;
3115 offset = round_down(offset, sectorsize);
3116 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, offset, sectorsize);
3120 if (em->block_start == EXTENT_MAP_HOLE)
3121 ret = RANGE_BOUNDARY_HOLE;
3122 else if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
3123 ret = RANGE_BOUNDARY_PREALLOC_EXTENT;
3125 ret = RANGE_BOUNDARY_WRITTEN_EXTENT;
3127 free_extent_map(em);
3131 static int btrfs_zero_range(struct inode *inode,
3136 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
3137 struct extent_map *em;
3138 struct extent_changeset *data_reserved = NULL;
3141 const u64 sectorsize = btrfs_inode_sectorsize(inode);
3142 u64 alloc_start = round_down(offset, sectorsize);
3143 u64 alloc_end = round_up(offset + len, sectorsize);
3144 u64 bytes_to_reserve = 0;
3145 bool space_reserved = false;
3147 inode_dio_wait(inode);
3149 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, alloc_start,
3150 alloc_end - alloc_start);
3157 * Avoid hole punching and extent allocation for some cases. More cases
3158 * could be considered, but these are unlikely common and we keep things
3159 * as simple as possible for now. Also, intentionally, if the target
3160 * range contains one or more prealloc extents together with regular
3161 * extents and holes, we drop all the existing extents and allocate a
3162 * new prealloc extent, so that we get a larger contiguous disk extent.
3164 if (em->start <= alloc_start &&
3165 test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3166 const u64 em_end = em->start + em->len;
3168 if (em_end >= offset + len) {
3170 * The whole range is already a prealloc extent,
3171 * do nothing except updating the inode's i_size if
3174 free_extent_map(em);
3175 ret = btrfs_fallocate_update_isize(inode, offset + len,
3180 * Part of the range is already a prealloc extent, so operate
3181 * only on the remaining part of the range.
3183 alloc_start = em_end;
3184 ASSERT(IS_ALIGNED(alloc_start, sectorsize));
3185 len = offset + len - alloc_start;
3186 offset = alloc_start;
3187 alloc_hint = em->block_start + em->len;
3189 free_extent_map(em);
3191 if (BTRFS_BYTES_TO_BLKS(fs_info, offset) ==
3192 BTRFS_BYTES_TO_BLKS(fs_info, offset + len - 1)) {
3193 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, alloc_start,
3200 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3201 free_extent_map(em);
3202 ret = btrfs_fallocate_update_isize(inode, offset + len,
3206 if (len < sectorsize && em->block_start != EXTENT_MAP_HOLE) {
3207 free_extent_map(em);
3208 ret = btrfs_truncate_block(inode, offset, len, 0);
3210 ret = btrfs_fallocate_update_isize(inode,
3215 free_extent_map(em);
3216 alloc_start = round_down(offset, sectorsize);
3217 alloc_end = alloc_start + sectorsize;
3221 alloc_start = round_up(offset, sectorsize);
3222 alloc_end = round_down(offset + len, sectorsize);
3225 * For unaligned ranges, check the pages at the boundaries, they might
3226 * map to an extent, in which case we need to partially zero them, or
3227 * they might map to a hole, in which case we need our allocation range
3230 if (!IS_ALIGNED(offset, sectorsize)) {
3231 ret = btrfs_zero_range_check_range_boundary(inode, offset);
3234 if (ret == RANGE_BOUNDARY_HOLE) {
3235 alloc_start = round_down(offset, sectorsize);
3237 } else if (ret == RANGE_BOUNDARY_WRITTEN_EXTENT) {
3238 ret = btrfs_truncate_block(inode, offset, 0, 0);
3246 if (!IS_ALIGNED(offset + len, sectorsize)) {
3247 ret = btrfs_zero_range_check_range_boundary(inode,
3251 if (ret == RANGE_BOUNDARY_HOLE) {
3252 alloc_end = round_up(offset + len, sectorsize);
3254 } else if (ret == RANGE_BOUNDARY_WRITTEN_EXTENT) {
3255 ret = btrfs_truncate_block(inode, offset + len, 0, 1);
3264 if (alloc_start < alloc_end) {
3265 struct extent_state *cached_state = NULL;
3266 const u64 lockstart = alloc_start;
3267 const u64 lockend = alloc_end - 1;
3269 bytes_to_reserve = alloc_end - alloc_start;
3270 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode),
3274 space_reserved = true;
3275 ret = btrfs_punch_hole_lock_range(inode, lockstart, lockend,
3279 ret = btrfs_qgroup_reserve_data(BTRFS_I(inode), &data_reserved,
3280 alloc_start, bytes_to_reserve);
3283 ret = btrfs_prealloc_file_range(inode, mode, alloc_start,
3284 alloc_end - alloc_start,
3286 offset + len, &alloc_hint);
3287 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
3288 lockend, &cached_state);
3289 /* btrfs_prealloc_file_range releases reserved space on error */
3291 space_reserved = false;
3295 ret = btrfs_fallocate_update_isize(inode, offset + len, mode);
3297 if (ret && space_reserved)
3298 btrfs_free_reserved_data_space(BTRFS_I(inode), data_reserved,
3299 alloc_start, bytes_to_reserve);
3300 extent_changeset_free(data_reserved);
3305 static long btrfs_fallocate(struct file *file, int mode,
3306 loff_t offset, loff_t len)
3308 struct inode *inode = file_inode(file);
3309 struct extent_state *cached_state = NULL;
3310 struct extent_changeset *data_reserved = NULL;
3311 struct falloc_range *range;
3312 struct falloc_range *tmp;
3313 struct list_head reserve_list;
3321 struct extent_map *em;
3322 int blocksize = btrfs_inode_sectorsize(inode);
3325 alloc_start = round_down(offset, blocksize);
3326 alloc_end = round_up(offset + len, blocksize);
3327 cur_offset = alloc_start;
3329 /* Make sure we aren't being give some crap mode */
3330 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
3331 FALLOC_FL_ZERO_RANGE))
3334 if (mode & FALLOC_FL_PUNCH_HOLE)
3335 return btrfs_punch_hole(inode, offset, len);
3338 * Only trigger disk allocation, don't trigger qgroup reserve
3340 * For qgroup space, it will be checked later.
3342 if (!(mode & FALLOC_FL_ZERO_RANGE)) {
3343 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode),
3344 alloc_end - alloc_start);
3351 if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size) {
3352 ret = inode_newsize_ok(inode, offset + len);
3358 * TODO: Move these two operations after we have checked
3359 * accurate reserved space, or fallocate can still fail but
3360 * with page truncated or size expanded.
3362 * But that's a minor problem and won't do much harm BTW.
3364 if (alloc_start > inode->i_size) {
3365 ret = btrfs_cont_expand(inode, i_size_read(inode),
3369 } else if (offset + len > inode->i_size) {
3371 * If we are fallocating from the end of the file onward we
3372 * need to zero out the end of the block if i_size lands in the
3373 * middle of a block.
3375 ret = btrfs_truncate_block(inode, inode->i_size, 0, 0);
3381 * wait for ordered IO before we have any locks. We'll loop again
3382 * below with the locks held.
3384 ret = btrfs_wait_ordered_range(inode, alloc_start,
3385 alloc_end - alloc_start);
3389 if (mode & FALLOC_FL_ZERO_RANGE) {
3390 ret = btrfs_zero_range(inode, offset, len, mode);
3391 inode_unlock(inode);
3395 locked_end = alloc_end - 1;
3397 struct btrfs_ordered_extent *ordered;
3399 /* the extent lock is ordered inside the running
3402 lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
3403 locked_end, &cached_state);
3404 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode),
3408 ordered->file_offset + ordered->num_bytes > alloc_start &&
3409 ordered->file_offset < alloc_end) {
3410 btrfs_put_ordered_extent(ordered);
3411 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
3412 alloc_start, locked_end,
3415 * we can't wait on the range with the transaction
3416 * running or with the extent lock held
3418 ret = btrfs_wait_ordered_range(inode, alloc_start,
3419 alloc_end - alloc_start);
3424 btrfs_put_ordered_extent(ordered);
3429 /* First, check if we exceed the qgroup limit */
3430 INIT_LIST_HEAD(&reserve_list);
3431 while (cur_offset < alloc_end) {
3432 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,
3433 alloc_end - cur_offset);
3438 last_byte = min(extent_map_end(em), alloc_end);
3439 actual_end = min_t(u64, extent_map_end(em), offset + len);
3440 last_byte = ALIGN(last_byte, blocksize);
3441 if (em->block_start == EXTENT_MAP_HOLE ||
3442 (cur_offset >= inode->i_size &&
3443 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
3444 ret = add_falloc_range(&reserve_list, cur_offset,
3445 last_byte - cur_offset);
3447 free_extent_map(em);
3450 ret = btrfs_qgroup_reserve_data(BTRFS_I(inode),
3451 &data_reserved, cur_offset,
3452 last_byte - cur_offset);
3454 cur_offset = last_byte;
3455 free_extent_map(em);
3460 * Do not need to reserve unwritten extent for this
3461 * range, free reserved data space first, otherwise
3462 * it'll result in false ENOSPC error.
3464 btrfs_free_reserved_data_space(BTRFS_I(inode),
3465 data_reserved, cur_offset,
3466 last_byte - cur_offset);
3468 free_extent_map(em);
3469 cur_offset = last_byte;
3473 * If ret is still 0, means we're OK to fallocate.
3474 * Or just cleanup the list and exit.
3476 list_for_each_entry_safe(range, tmp, &reserve_list, list) {
3478 ret = btrfs_prealloc_file_range(inode, mode,
3480 range->len, i_blocksize(inode),
3481 offset + len, &alloc_hint);
3483 btrfs_free_reserved_data_space(BTRFS_I(inode),
3484 data_reserved, range->start,
3486 list_del(&range->list);
3493 * We didn't need to allocate any more space, but we still extended the
3494 * size of the file so we need to update i_size and the inode item.
3496 ret = btrfs_fallocate_update_isize(inode, actual_end, mode);
3498 unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
3501 inode_unlock(inode);
3502 /* Let go of our reservation. */
3503 if (ret != 0 && !(mode & FALLOC_FL_ZERO_RANGE))
3504 btrfs_free_reserved_data_space(BTRFS_I(inode), data_reserved,
3505 cur_offset, alloc_end - cur_offset);
3506 extent_changeset_free(data_reserved);
3510 static loff_t find_desired_extent(struct inode *inode, loff_t offset,
3513 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3514 struct extent_map *em = NULL;
3515 struct extent_state *cached_state = NULL;
3516 loff_t i_size = inode->i_size;
3523 if (i_size == 0 || offset >= i_size)
3527 * offset can be negative, in this case we start finding DATA/HOLE from
3528 * the very start of the file.
3530 start = max_t(loff_t, 0, offset);
3532 lockstart = round_down(start, fs_info->sectorsize);
3533 lockend = round_up(i_size, fs_info->sectorsize);
3534 if (lockend <= lockstart)
3535 lockend = lockstart + fs_info->sectorsize;
3537 len = lockend - lockstart + 1;
3539 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
3542 while (start < i_size) {
3543 em = btrfs_get_extent_fiemap(BTRFS_I(inode), start, len);
3550 if (whence == SEEK_HOLE &&
3551 (em->block_start == EXTENT_MAP_HOLE ||
3552 test_bit(EXTENT_FLAG_PREALLOC, &em->flags)))
3554 else if (whence == SEEK_DATA &&
3555 (em->block_start != EXTENT_MAP_HOLE &&
3556 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)))
3559 start = em->start + em->len;
3560 free_extent_map(em);
3564 free_extent_map(em);
3565 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
3570 if (whence == SEEK_DATA && start >= i_size)
3573 offset = min_t(loff_t, start, i_size);
3579 static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence)
3581 struct inode *inode = file->f_mapping->host;
3585 return generic_file_llseek(file, offset, whence);
3588 inode_lock_shared(inode);
3589 offset = find_desired_extent(inode, offset, whence);
3590 inode_unlock_shared(inode);
3597 return vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
3600 static int btrfs_file_open(struct inode *inode, struct file *filp)
3602 filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
3603 return generic_file_open(inode, filp);
3606 static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
3610 if (iocb->ki_flags & IOCB_DIRECT) {
3611 struct inode *inode = file_inode(iocb->ki_filp);
3613 inode_lock_shared(inode);
3614 ret = btrfs_direct_IO(iocb, to);
3615 inode_unlock_shared(inode);
3620 return generic_file_buffered_read(iocb, to, ret);
3623 const struct file_operations btrfs_file_operations = {
3624 .llseek = btrfs_file_llseek,
3625 .read_iter = btrfs_file_read_iter,
3626 .splice_read = generic_file_splice_read,
3627 .write_iter = btrfs_file_write_iter,
3628 .splice_write = iter_file_splice_write,
3629 .mmap = btrfs_file_mmap,
3630 .open = btrfs_file_open,
3631 .release = btrfs_release_file,
3632 .fsync = btrfs_sync_file,
3633 .fallocate = btrfs_fallocate,
3634 .unlocked_ioctl = btrfs_ioctl,
3635 #ifdef CONFIG_COMPAT
3636 .compat_ioctl = btrfs_compat_ioctl,
3638 .remap_file_range = btrfs_remap_file_range,
3641 void __cold btrfs_auto_defrag_exit(void)
3643 kmem_cache_destroy(btrfs_inode_defrag_cachep);
3646 int __init btrfs_auto_defrag_init(void)
3648 btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
3649 sizeof(struct inode_defrag), 0,
3652 if (!btrfs_inode_defrag_cachep)
3658 int btrfs_fdatawrite_range(struct inode *inode, loff_t start, loff_t end)
3663 * So with compression we will find and lock a dirty page and clear the
3664 * first one as dirty, setup an async extent, and immediately return
3665 * with the entire range locked but with nobody actually marked with
3666 * writeback. So we can't just filemap_write_and_wait_range() and
3667 * expect it to work since it will just kick off a thread to do the
3668 * actual work. So we need to call filemap_fdatawrite_range _again_
3669 * since it will wait on the page lock, which won't be unlocked until
3670 * after the pages have been marked as writeback and so we're good to go
3671 * from there. We have to do this otherwise we'll miss the ordered
3672 * extents and that results in badness. Please Josef, do not think you
3673 * know better and pull this out at some point in the future, it is
3674 * right and you are wrong.
3676 ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
3677 if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
3678 &BTRFS_I(inode)->runtime_flags))
3679 ret = filemap_fdatawrite_range(inode->i_mapping, start, end);