1 files changed, 70 insertions, 60 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index f80254d82f40..eb1bac7c8553 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -477,6 +477,47 @@ static void btrfs_drop_pages(struct page **pages, size_t num_pages)
 	}
 }
 
+static int btrfs_find_new_delalloc_bytes(struct btrfs_inode *inode,
+					 const u64 start,
+					 const u64 len,
+					 struct extent_state **cached_state)
+{
+	u64 search_start = start;
+	const u64 end = start + len - 1;
+
+	while (search_start < end) {
+		const u64 search_len = end - search_start + 1;
+		struct extent_map *em;
+		u64 em_len;
+		int ret = 0;
+
+		em = btrfs_get_extent(inode, NULL, 0, search_start,
+				      search_len, 0);
+		if (IS_ERR(em))
+			return PTR_ERR(em);
+
+		if (em->block_start != EXTENT_MAP_HOLE)
+			goto next;
+
+		em_len = em->len;
+		if (em->start < search_start)
+			em_len -= search_start - em->start;
+		if (em_len > search_len)
+			em_len = search_len;
+
+		ret = set_extent_bit(&inode->io_tree, search_start,
+				     search_start + em_len - 1,
+				     EXTENT_DELALLOC_NEW,
+				     NULL, cached_state, GFP_NOFS);
+next:
+		search_start = extent_map_end(em);
+		free_extent_map(em);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
 /*
  * after copy_from_user, pages need to be dirtied and we need to make
  * sure holes are created between the current EOF and the start of
@@ -497,14 +538,34 @@ int btrfs_dirty_pages(struct inode *inode, struct page **pages,
 	u64 end_of_last_block;
 	u64 end_pos = pos + write_bytes;
 	loff_t isize = i_size_read(inode);
+	unsigned int extra_bits = 0;
 
 	start_pos = pos & ~((u64) fs_info->sectorsize - 1);
 	num_bytes = round_up(write_bytes + pos - start_pos,
 			     fs_info->sectorsize);
 
 	end_of_last_block = start_pos + num_bytes - 1;
+
+	if (!btrfs_is_free_space_inode(BTRFS_I(inode))) {
+		if (start_pos >= isize &&
+		    !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)) {
+			/*
+			 * There can't be any extents following eof in this case
+			 * so just set the delalloc new bit for the range
+			 * directly.
+			 */
+			extra_bits |= EXTENT_DELALLOC_NEW;
+		} else {
+			err = btrfs_find_new_delalloc_bytes(BTRFS_I(inode),
+							    start_pos,
+							    num_bytes, cached);
+			if (err)
+				return err;
+		}
+	}
+
 	err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
-					cached, 0);
+					extra_bits, cached, 0);
 	if (err)
 		return err;
 
@@ -1404,47 +1465,6 @@ fail:
 
 }
 
-static int btrfs_find_new_delalloc_bytes(struct btrfs_inode *inode,
-					 const u64 start,
-					 const u64 len,
-					 struct extent_state **cached_state)
-{
-	u64 search_start = start;
-	const u64 end = start + len - 1;
-
-	while (search_start < end) {
-		const u64 search_len = end - search_start + 1;
-		struct extent_map *em;
-		u64 em_len;
-		int ret = 0;
-
-		em = btrfs_get_extent(inode, NULL, 0, search_start,
-				      search_len, 0);
-		if (IS_ERR(em))
-			return PTR_ERR(em);
-
-		if (em->block_start != EXTENT_MAP_HOLE)
-			goto next;
-
-		em_len = em->len;
-		if (em->start < search_start)
-			em_len -= search_start - em->start;
-		if (em_len > search_len)
-			em_len = search_len;
-
-		ret = set_extent_bit(&inode->io_tree, search_start,
-				     search_start + em_len - 1,
-				     EXTENT_DELALLOC_NEW,
-				     NULL, cached_state, GFP_NOFS);
-next:
-		search_start = extent_map_end(em);
-		free_extent_map(em);
-		if (ret)
-			return ret;
-	}
-	return 0;
-}
-
 /*
  * This function locks the extent and properly waits for data=ordered extents
  * to finish before allowing the pages to be modified if need.
@@ -1473,10 +1493,8 @@ lock_and_cleanup_extent_if_need(struct btrfs_inode *inode, struct page **pages,
 		+ round_up(pos + write_bytes - start_pos,
 			   fs_info->sectorsize) - 1;
 
-	if (start_pos < inode->vfs_inode.i_size ||
-	    (inode->flags & BTRFS_INODE_PREALLOC)) {
+	if (start_pos < inode->vfs_inode.i_size) {
 		struct btrfs_ordered_extent *ordered;
-		unsigned int clear_bits;
 
 		lock_extent_bits(&inode->io_tree, start_pos, last_pos,
 				cached_state);
@@ -1498,19 +1516,10 @@ lock_and_cleanup_extent_if_need(struct btrfs_inode *inode, struct page **pages,
 		}
 		if (ordered)
 			btrfs_put_ordered_extent(ordered);
-		ret = btrfs_find_new_delalloc_bytes(inode, start_pos,
-						    last_pos - start_pos + 1,
-						    cached_state);
-		clear_bits = EXTENT_DIRTY | EXTENT_DELALLOC |
-			EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG;
-		if (ret)
-			clear_bits |= EXTENT_DELALLOC_NEW | EXTENT_LOCKED;
-		clear_extent_bit(&inode->io_tree, start_pos,
-				 last_pos, clear_bits,
-				 (clear_bits & EXTENT_LOCKED) ? 1 : 0,
-				 0, cached_state, GFP_NOFS);
-		if (ret)
-			return ret;
+		clear_extent_bit(&inode->io_tree, start_pos, last_pos,
+				 EXTENT_DIRTY | EXTENT_DELALLOC |
+				 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
+				 0, 0, cached_state, GFP_NOFS);
 		*lockstart = start_pos;
 		*lockend = last_pos;
 		ret = 1;
@@ -2048,6 +2057,8 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	len = (u64)end - (u64)start + 1;
 	trace_btrfs_sync_file(file, datasync);
 
+	btrfs_init_log_ctx(&ctx, inode);
+
 	/*
 	 * We write the dirty pages in the range and wait until they complete
 	 * out of the ->i_mutex. If so, we can flush the dirty pages by
@@ -2194,8 +2205,6 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	}
 	trans->sync = true;
 
-	btrfs_init_log_ctx(&ctx, inode);
-
 	ret = btrfs_log_dentry_safe(trans, root, dentry, start, end, &ctx);
 	if (ret < 0) {
 		/* Fallthrough and commit/free transaction. */
@@ -2253,6 +2262,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 		ret = btrfs_end_transaction(trans);
 	}
 out:
+	ASSERT(list_empty(&ctx.list));
 	err = file_check_and_advance_wb_err(file);
 	if (!ret)
 		ret = err;