fuse: rcu-delay freeing fuse_conn

makes ->permission() and ->d_revalidate() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 1c15613..d468643 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -918,7 +918,7 @@
 
 static void fuse_free_conn(struct fuse_conn *fc)
 {
-	kfree(fc);
+	kfree_rcu(fc, rcu);
 }
 
 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)