commit 04303d8ad06985bed4ea4f46018fc8f55a0962a8
author Yan, Zheng <zyan@redhat.com> Thu Apr 21 12:11:54 2016 +0800
committer Ilya Dryomov <idryomov@gmail.com> Thu May 26 01:15:33 2016 +0200
tree 1d0c59cb25abf8882c3d8d084f28cb04bd2125fe
parent 3f38495409b613071021fca86629df7ae81820ad

ceph: use CEPH_MDS_OP_RMXATTR request to remove xattr

Setxattr with NULL value and XATTR_REPLACE flag should be equivalent
to removexattr. But current MDS does not support deleting vxattrs through
MDS_OP_SETXATTR request. The workaround is sending MDS_OP_RMXATTR request
if setxattr actually removs xattr.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

fs/ceph/xattr.c

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 5afabc4b..426c83c 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -886,6 +886,7 @@
 	struct ceph_mds_request *req;
 	struct ceph_mds_client *mdsc = fsc->mdsc;
 	struct ceph_pagelist *pagelist = NULL;
+	int op = CEPH_MDS_OP_SETXATTR;
 	int err;
 
 	if (size > 0) {
@@ -899,20 +900,21 @@
 		if (err)
 			goto out;
 	} else if (!value) {
-		flags |= CEPH_XATTR_REMOVE;
+		if (flags & CEPH_XATTR_REPLACE)
+			op = CEPH_MDS_OP_RMXATTR;
+		else
+			flags |= CEPH_XATTR_REMOVE;
 	}
 
 	dout("setxattr value=%.*s\n", (int)size, value);
 
 	/* do request */
-	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
-				       USE_AUTH_MDS);
+	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 	if (IS_ERR(req)) {
 		err = PTR_ERR(req);
 		goto out;
 	}
 
-	req->r_args.setxattr.flags = cpu_to_le32(flags);
 	req->r_path2 = kstrdup(name, GFP_NOFS);
 	if (!req->r_path2) {
 		ceph_mdsc_put_request(req);
@@ -920,8 +922,11 @@
 		goto out;
 	}
 
-	req->r_pagelist = pagelist;
-	pagelist = NULL;
+	if (op == CEPH_MDS_OP_SETXATTR) {
+		req->r_args.setxattr.flags = cpu_to_le32(flags);
+		req->r_pagelist = pagelist;
+		pagelist = NULL;
+	}
 
 	req->r_inode = inode;
 	ihold(inode);