ceph: check if mds create snaprealm when setting quota

If mds does not, return -EOPNOTSUPP.

Link: http://tracker.ceph.com/issues/23491
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 7e72348..315f7e6 100644 (file)
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -228,7 +228,15 @@ static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
 
 static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
 {
-       return (ci->i_max_files || ci->i_max_bytes);
+       bool ret = false;
+       spin_lock(&ci->i_ceph_lock);
+       if ((ci->i_max_files || ci->i_max_bytes) &&
+           ci->i_vino.snap == CEPH_NOSNAP &&
+           ci->i_snap_realm &&
+           ci->i_snap_realm->ino == ci->i_vino.ino)
+               ret = true;
+       spin_unlock(&ci->i_ceph_lock);
+       return ret;
 }
 
 static size_t ceph_vxattrcb_quota(struct ceph_inode_info *ci, char *val,
@@ -1008,14 +1016,19 @@ int __ceph_setxattr(struct inode *inode, const char *name,
        char *newval = NULL;
        struct ceph_inode_xattr *xattr = NULL;
        int required_blob_size;
+       bool check_realm = false;
        bool lock_snap_rwsem = false;
 
        if (ceph_snap(inode) != CEPH_NOSNAP)
                return -EROFS;
 
        vxattr = ceph_match_vxattr(inode, name);
-       if (vxattr && vxattr->readonly)
-               return -EOPNOTSUPP;
+       if (vxattr) {
+               if (vxattr->readonly)
+                       return -EOPNOTSUPP;
+               if (value && !strncmp(vxattr->name, "ceph.quota", 10))
+                       check_realm = true;
+       }
 
        /* pass any unhandled ceph.* xattrs through to the MDS */
        if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
@@ -1109,6 +1122,15 @@ do_sync_unlocked:
                err = -EBUSY;
        } else {
                err = ceph_sync_setxattr(inode, name, value, size, flags);
+               if (err >= 0 && check_realm) {
+                       /* check if snaprealm was created for quota inode */
+                       spin_lock(&ci->i_ceph_lock);
+                       if ((ci->i_max_files || ci->i_max_bytes) &&
+                           !(ci->i_snap_realm &&
+                             ci->i_snap_realm->ino == ci->i_vino.ino))
+                               err = -EOPNOTSUPP;
+                       spin_unlock(&ci->i_ceph_lock);
+               }
        }
 out:
        ceph_free_cap_flush(prealloc_cf);