diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index fc2d21b0a02259e1e41270a26b409f563cd1a79d..d88f2dc4d045d757e39befe387f8d9a07095ad83 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1427,16 +1427,11 @@ static noinline int check_can_nocow(struct inode *inode, loff_t pos,
 
 	num_bytes = lockend - lockstart + 1;
 	ret = can_nocow_extent(inode, lockstart, &num_bytes, NULL, NULL, NULL);
-	if (ret <= 0) {
+	if (ret <= 0)
 		ret = 0;
-	} else {
-		clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
-				 EXTENT_DIRTY | EXTENT_DELALLOC |
-				 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
-				 NULL, GFP_NOFS);
+	else
 		*write_bytes = min_t(size_t, *write_bytes ,
 				     num_bytes - pos + lockstart);
-	}
 
 	unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8dba152883d300fa1c0d6092c9700757aa1df4aa..0182f081d499ff3abfc29f5db5993f5d795330ba 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6557,6 +6557,7 @@ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
 	int ret;
 	struct extent_buffer *leaf;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	struct btrfs_file_extent_item *fi;
 	struct btrfs_key key;
 	u64 disk_bytenr;
@@ -6633,6 +6634,20 @@ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
 
 	if (btrfs_extent_readonly(root, disk_bytenr))
 		goto out;
+
+	num_bytes = min(offset + *len, extent_end) - offset;
+	if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) {
+		u64 range_end;
+
+		range_end = round_up(offset + num_bytes, root->sectorsize) - 1;
+		ret = test_range_bit(io_tree, offset, range_end,
+				     EXTENT_DELALLOC, 0, NULL);
+		if (ret) {
+			ret = -EAGAIN;
+			goto out;
+		}
+	}
+
 	btrfs_release_path(path);
 
 	/*
@@ -6661,7 +6676,6 @@ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
 	 */
 	disk_bytenr += backref_offset;
 	disk_bytenr += offset - key.offset;
-	num_bytes = min(offset + *len, extent_end) - offset;
 	if (csum_exist_in_range(root, disk_bytenr, num_bytes))
 				goto out;
 	/*