btrfs: allow cross-subvolume file clone
Lift the EXDEV condition and allow different root trees for files being
cloned, then pass source inode's root when searching for extents.
Cloning is not allowed to cross vfsmounts, ie. when two subvolumes from
one filesystem are mounted separately.
Signed-off-by: David Sterba <dsterba@suse.cz>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 0e92e57..7011871 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2340,6 +2340,10 @@
goto out_drop_write;
}
+ ret = -EXDEV;
+ if (src_file->f_path.mnt != file->f_path.mnt)
+ goto out_fput;
+
src = src_file->f_dentry->d_inode;
ret = -EINVAL;
@@ -2360,7 +2364,7 @@
goto out_fput;
ret = -EXDEV;
- if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
+ if (src->i_sb != inode->i_sb)
goto out_fput;
ret = -ENOMEM;
@@ -2434,13 +2438,14 @@
* note the key will change type as we walk through the
* tree.
*/
- ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
+ 0, 0);
if (ret < 0)
goto out;
nritems = btrfs_header_nritems(path->nodes[0]);
if (path->slots[0] >= nritems) {
- ret = btrfs_next_leaf(root, path);
+ ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
if (ret < 0)
goto out;
if (ret > 0)