ceph: make d_revalidate call fscrypt revalidator for encrypted dentries

If we have a dentry which represents a no-key name, then we need to test
whether the parent directory's encryption key has since been added.  Do
that before we test anything else about the dentry.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-and-tested-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/dir.c

@@ -1782,6 +1782,10 @@ static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
 	struct inode *dir, *inode;
 	struct ceph_mds_client *mdsc;
 
+	valid = fscrypt_d_revalidate(dentry, flags);
+	if (valid <= 0)
+		return valid;
+
 	if (flags & LOOKUP_RCU) {
 		parent = READ_ONCE(dentry->d_parent);
 		dir = d_inode_rcu(parent);
@@ -1794,8 +1798,9 @@ static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
 		inode = d_inode(dentry);
 	}
 
-	dout("d_revalidate %p '%pd' inode %p offset 0x%llx\n", dentry,
-	     dentry, inode, ceph_dentry(dentry)->offset);
+	dout("d_revalidate %p '%pd' inode %p offset 0x%llx nokey %d\n", dentry,
+	     dentry, inode, ceph_dentry(dentry)->offset,
+	     !!(dentry->d_flags & DCACHE_NOKEY_NAME));
 
 	mdsc = ceph_sb_to_client(dir->i_sb)->mdsc;