ceph: pass parent inode info to ceph_encode_dentry_release if we have it

If we have a parent inode reference already, then we don't need to
go back up the directory tree to find one.

Link: http://tracker.ceph.com/issues/18148
Signed-off-by: Jeff Layton <[e-mail]>
Reviewed-by: Yan, Zheng <[e-mail]>
Signed-off-by: Ilya Dryomov <[e-mail]>

fs/ceph/caps.c

···
 }
 
 int ceph_encode_dentry_release(void **p, struct dentry *dentry,
+			       struct inode *dir,
 			       int mds, int drop, int unless)
 {
-	struct dentry *parent;
+	struct dentry *parent = NULL;
 	struct ceph_mds_request_release *rel = *p;
 	struct ceph_dentry_info *di = ceph_dentry(dentry);
 	int force = 0;
···
 	spin_lock(&dentry->d_lock);
 	if (di->lease_session && di->lease_session->s_mds == mds)
 		force = 1;
-	parent = dget(dentry->d_parent);
+	if (!dir) {
+		parent = dget(dentry->d_parent);
+		dir = d_inode(parent);
+	}
 	spin_unlock(&dentry->d_lock);
 
-	ret = ceph_encode_inode_release(p, d_inode(parent), mds, drop,
-					unless, force);
+	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
 	dput(parent);
 
 	spin_lock(&dentry->d_lock);

fs/ceph/mds_client.c

···
 		      mds, req->r_inode_drop, req->r_inode_unless, 0);
 	if (req->r_dentry_drop)
 		releases += ceph_encode_dentry_release(&p, req->r_dentry,
-		       mds, req->r_dentry_drop, req->r_dentry_unless);
+				req->r_locked_dir, mds, req->r_dentry_drop,
+				req->r_dentry_unless);
 	if (req->r_old_dentry_drop)
 		releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
-		       mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
+				req->r_old_dentry_dir, mds,
+				req->r_old_dentry_drop,
+				req->r_old_dentry_unless);
 	if (req->r_old_inode_drop)
 		releases += ceph_encode_inode_release(&p,
 		      d_inode(req->r_old_dentry),

fs/ceph/super.h

···
 extern int ceph_encode_inode_release(void **p, struct inode *inode,
 				     int mds, int drop, int unless, int force);
 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
+				      struct inode *dir,
 				      int mds, int drop, int unless);
 
 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,