constify btrfs_mksubvol()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 7acbd2c..8270f43 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -836,7 +836,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
* sys_mkdirat and vfs_mkdir, but we only do a single component lookup
* inside this filesystem so it's quite a bit simpler.
*/
-static noinline int btrfs_mksubvol(struct path *parent,
+static noinline int btrfs_mksubvol(const struct path *parent,
char *name, int namelen,
struct btrfs_root *snap_src,
u64 *async_transid, bool readonly,
