btrfs: Make reada_tree_block_flagged private

This function is used only for the readahead machinery. It makes no
sense to keep it external to reada.c file. Place it above its sole
caller and make it static. No functional changes.
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/disk-io.c

@@ -1038,35 +1038,6 @@ void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr)
 		free_extent_buffer(buf);
 }
 
-int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
-			 int mirror_num, struct extent_buffer **eb)
-{
-	struct extent_buffer *buf = NULL;
-	int ret;
-
-	buf = btrfs_find_create_tree_block(fs_info, bytenr);
-	if (IS_ERR(buf))
-		return 0;
-
-	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
-
-	ret = read_extent_buffer_pages(buf, WAIT_PAGE_LOCK, mirror_num);
-	if (ret) {
-		free_extent_buffer_stale(buf);
-		return ret;
-	}
-
-	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
-		free_extent_buffer_stale(buf);
-		return -EIO;
-	} else if (extent_buffer_uptodate(buf)) {
-		*eb = buf;
-	} else {
-		free_extent_buffer(buf);
-	}
-	return 0;
-}
-
 struct extent_buffer *btrfs_find_create_tree_block(
 						struct btrfs_fs_info *fs_info,
 						u64 bytenr)

fs/btrfs/disk-io.h

@@ -45,8 +45,6 @@ struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
 				      u64 parent_transid, int level,
 				      struct btrfs_key *first_key);
 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
-int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
-			 int mirror_num, struct extent_buffer **eb);
 struct extent_buffer *btrfs_find_create_tree_block(
 						struct btrfs_fs_info *fs_info,
 						u64 bytenr);

fs/btrfs/reada.c

@@ -639,6 +639,35 @@ static int reada_pick_zone(struct btrfs_device *dev)
 	return 1;
 }
 
+static int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
+				    int mirror_num, struct extent_buffer **eb)
+{
+	struct extent_buffer *buf = NULL;
+	int ret;
+
+	buf = btrfs_find_create_tree_block(fs_info, bytenr);
+	if (IS_ERR(buf))
+		return 0;
+
+	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
+
+	ret = read_extent_buffer_pages(buf, WAIT_PAGE_LOCK, mirror_num);
+	if (ret) {
+		free_extent_buffer_stale(buf);
+		return ret;
+	}
+
+	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
+		free_extent_buffer_stale(buf);
+		return -EIO;
+	} else if (extent_buffer_uptodate(buf)) {
+		*eb = buf;
+	} else {
+		free_extent_buffer(buf);
+	}
+	return 0;
+}
+
 static int reada_start_machine_dev(struct btrfs_device *dev)
 {
 	struct btrfs_fs_info *fs_info = dev->fs_info;