lustre/mdc: Check for all attributes validity in revalidate

GETATTR needs to return attributes protected by different bits, so
we need to ensure all we have locks with all of those bits, not
just UPDATE bit
Signed-off-by: Alexey Lyashkov <alexey_lyashkov@xyratex.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: http://review.whamcloud.com/6460
Xyratex-bug-id: MRP-1052
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3240Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: wangdi <di.wang@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/mdc/mdc_locks.c

@@ -1061,7 +1061,20 @@ int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
 		fid_build_reg_res_name(fid, &res_id);
 		switch (it->it_op) {
 		case IT_GETATTR:
-			policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
+			/* File attributes are held under multiple bits:
+			 * nlink is under lookup lock, size and times are
+			 * under UPDATE lock and recently we've also got
+			 * a separate permissions lock for owner/group/acl that
+			 * were protected by lookup lock before.
+			 * Getattr must provide all of that information,
+			 * so we need to ensure we have all of those locks.
+			 * Unfortunately, if the bits are split across multiple
+			 * locks, there's no easy way to match all of them here,
+			 * so an extra RPC would be performed to fetch all
+			 * of those bits at once for now. */
+			policy.l_inodebits.bits = MDS_INODELOCK_UPDATE |
+						  MDS_INODELOCK_LOOKUP |
+						  MDS_INODELOCK_PERM;
 			break;
 		case IT_LAYOUT:
 			policy.l_inodebits.bits = MDS_INODELOCK_LAYOUT;
@@ -1070,6 +1083,7 @@ int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
 			policy.l_inodebits.bits = MDS_INODELOCK_LOOKUP;
 			break;
 		}
+
 		mode = ldlm_lock_match(exp->exp_obd->obd_namespace,
 				       LDLM_FL_BLOCK_GRANTED, &res_id,
 				       LDLM_IBITS, &policy,