[PATCH 02/17] lustre/mdc: Check for all attributes validity in revalidate

[Oleg Drokin <green@linuxhacker.ru>]

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-3240
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: wangdi <di.wang@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
---
 drivers/staging/lustre/lustre/mdc/mdc_locks.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/lustre/lustre/mdc/mdc_locks.c b/drivers/staging/lustre/lustre/mdc/mdc_locks.c
index 288a41e..1336d47 100644
--- a/drivers/staging/lustre/lustre/mdc/mdc_locks.c
+++ b/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,
-- 
1.8.5.3