From: "Yan, Zheng" <zyan@redhat.com>
Date: Wed, 14 Jun 2017 15:54:56 +0800
Subject: ceph: getattr before read on ceph.* xattrs
Git-commit: 1684dd03e9f59212775cafa50ea77b9ef5b263db
Patch-mainline: v4.13-rc1
References: FATE#324714

Previously we were returning values for quota, layout
xattrs without any kind of update -- the user just got
whatever happened to be in our cache.

Clearly this extra round trip has a cost, but reads of
these xattrs are fairly rare, happening on admin
intervention rather than in normal operation.

Link: http://tracker.ceph.com/issues/17939
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/xattr.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 75267cdd5dfd..11263f102e4c 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -756,6 +756,9 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 	/* let's see if a virtual xattr was requested */
 	vxattr = ceph_match_vxattr(inode, name);
 	if (vxattr) {
+		err = ceph_do_getattr(inode, 0, true);
+		if (err)
+			return err;
 		err = -ENODATA;
 		if (!(vxattr->exists_cb && !vxattr->exists_cb(ci)))
 			err = vxattr->getxattr_cb(ci, value, size);