ceph: properly drop caps for setattr request

For CEPH_SETATTR_ATIME, MDS needs to xlock filelock, Fsxrw caps
are not allowed for xlocked filelock.

For CEPH_SETATTR_SIZE request that truncates file to smaller size,
MDS needs to xlock filelock, Fsxrw caps are not allowed for xlocked
filelock.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/inode.c

@@ -2000,8 +2000,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			ceph_encode_timespec(&req->r_args.setattr.atime,
 					     &attr->ia_atime);
 			mask |= CEPH_SETATTR_ATIME;
-			release |= CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}
 	if (ia_valid & ATTR_MTIME) {
@@ -2022,8 +2022,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			ceph_encode_timespec(&req->r_args.setattr.mtime,
 					     &attr->ia_mtime);
 			mask |= CEPH_SETATTR_MTIME;
-			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}
 	if (ia_valid & ATTR_SIZE) {
@@ -2041,8 +2041,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			req->r_args.setattr.old_size =
 				cpu_to_le64(inode->i_size);
 			mask |= CEPH_SETATTR_SIZE;
-			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}