lustre/mdc: use ibits_known mask for lock match

Before revalidating a lock on the client, mask the lock bits against
the lock bits supported by the server (ibits_known), so newer clients
will find valid locks given by older server versions.
Signed-off-by: Patrick Farrell <paf@cray.com>
Signed-off-by: Alexey Lyashkov <alexey_lyashkov@xyratex.com>
Reviewed-on: http://review.whamcloud.com/8636
Xyratex-bug-id: MRP-1583
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4405Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/lustre_export.h

@@ -380,6 +380,14 @@ static inline bool imp_connect_lvb_type(struct obd_import *imp)
 		return false;
 }
 
+static inline __u64 exp_connect_ibits(struct obd_export *exp)
+{
+	struct obd_connect_data *ocd;
+
+	ocd = &exp->exp_connect_data;
+	return ocd->ocd_ibits_known;
+}
+
 extern struct obd_export *class_conn2export(struct lustre_handle *conn);
 extern struct obd_device *class_conn2obd(struct lustre_handle *conn);
 

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

@@ -160,6 +160,8 @@ ldlm_mode_t mdc_lock_match(struct obd_export *exp, __u64 flags,
 	ldlm_mode_t rc;
 
 	fid_build_reg_res_name(fid, &res_id);
+	/* LU-4405: Clear bits not supported by server */
+	policy->l_inodebits.bits &= exp_connect_ibits(exp);
 	rc = ldlm_lock_match(class_exp2obd(exp)->obd_namespace, flags,
 			     &res_id, type, policy, mode, lockh, 0);
 	return rc;
@@ -1087,10 +1089,10 @@ int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
 			break;
 		}
 
-		mode = ldlm_lock_match(exp->exp_obd->obd_namespace,
-				       LDLM_FL_BLOCK_GRANTED, &res_id,
+		mode = mdc_lock_match(exp, LDLM_FL_BLOCK_GRANTED, fid,
 				       LDLM_IBITS, &policy,
-				       LCK_CR|LCK_CW|LCK_PR|LCK_PW, &lockh, 0);
+				      LCK_CR | LCK_CW | LCK_PR | LCK_PW,
+				      &lockh);
 	}
 
 	if (mode) {