megaraid_sas: Fix for IO failing post OCR in SRIOV environment

Driver assumes that VFs always have peers present whenever they have
same LD IDs. But this is not the case.  This patch handles the above
mentioned by explicitly checking for a peer before making HA/non-HA path
decision.

Signed-off-by: Uday Lingala <uday.lingala@avagotech.com>
Signed-off-by: Sumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index b6fdb48..4484e63 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -393,6 +393,7 @@
 
 
 #define SGE_BUFFER_SIZE	4096
+#define MEGASAS_CLUSTER_ID_SIZE	16
 /*
  * define constants for device list query options
  */
@@ -1227,7 +1228,8 @@
 	*/
 	struct {
 #if defined(__BIG_ENDIAN_BITFIELD)
-		u32     reserved:26;
+		u32     reserved:25;
+		u32     passive:1;
 		u32     premiumFeatureMismatch:1;
 		u32     ctrlPropIncompatible:1;
 		u32     fwVersionMismatch:1;
@@ -1241,11 +1243,12 @@
 		u32     fwVersionMismatch:1;
 		u32     ctrlPropIncompatible:1;
 		u32     premiumFeatureMismatch:1;
-		u32     reserved:26;
+		u32     passive:1;
+		u32     reserved:25;
 #endif
 	} cluster;
 
-	char clusterId[16];                     /*7D4h */
+	char clusterId[MEGASAS_CLUSTER_ID_SIZE]; /*0x7D4 */
 	struct {
 		u8  maxVFsSupported;            /*0x7E4*/
 		u8  numVFsEnabled;              /*0x7E5*/
@@ -2126,7 +2129,9 @@
 	char skip_heartbeat_timer_del;
 	u8 requestorId;
 	char PlasmaFW111;
-	char mpio;
+	char clusterId[MEGASAS_CLUSTER_ID_SIZE];
+	u8 peerIsPresent;
+	u8 passive;
 	u16 throttlequeuedepth;
 	u8 mask_interrupts;
 	u16 max_chain_frame_sz;
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index a831327..3a3e7d0 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -1943,7 +1943,7 @@
 		writel(MFI_STOP_ADP, &instance->reg_set->doorbell);
 		/* Flush */
 		readl(&instance->reg_set->doorbell);
-		if (instance->mpio && instance->requestorId)
+		if (instance->requestorId && instance->peerIsPresent)
 			memset(instance->ld_ids, 0xff, MEGASAS_MAX_LD_IDS);
 	} else {
 		writel(MFI_STOP_ADP,
@@ -5182,7 +5182,9 @@
 
 	tmp_sectors = min_t(u32, max_sectors_1, max_sectors_2);
 
-	instance->mpio = ctrl_info->adapterOperations2.mpio;
+	instance->peerIsPresent = ctrl_info->cluster.peerIsPresent;
+	instance->passive = ctrl_info->cluster.passive;
+	memcpy(instance->clusterId, ctrl_info->clusterId, sizeof(instance->clusterId));
 	instance->UnevenSpanSupport =
 		ctrl_info->adapterOperations2.supportUnevenSpans;
 	if (instance->UnevenSpanSupport) {
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index be9c3f1..d9d0029 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -3325,27 +3325,37 @@
 	return ret;
 }
 
+/*SRIOV get other instance in cluster if any*/
+struct megasas_instance *megasas_get_peer_instance(struct megasas_instance *instance)
+{
+	int i;
+
+	for (i = 0; i < MAX_MGMT_ADAPTERS; i++) {
+		if (megasas_mgmt_info.instance[i] &&
+			(megasas_mgmt_info.instance[i] != instance) &&
+			 megasas_mgmt_info.instance[i]->requestorId &&
+			 megasas_mgmt_info.instance[i]->peerIsPresent &&
+			(memcmp((megasas_mgmt_info.instance[i]->clusterId),
+			instance->clusterId, MEGASAS_CLUSTER_ID_SIZE) == 0))
+			return megasas_mgmt_info.instance[i];
+	}
+	return NULL;
+}
+
 /* Check for a second path that is currently UP */
 int megasas_check_mpio_paths(struct megasas_instance *instance,
 	struct scsi_cmnd *scmd)
 {
-	int i, j, retval = (DID_RESET << 16);
+	struct megasas_instance *peer_instance = NULL;
+	int retval = (DID_RESET << 16);
 
-	if (instance->mpio && instance->requestorId) {
-		for (i = 0 ; i < MAX_MGMT_ADAPTERS ; i++)
-			for (j = 0 ; j < MAX_LOGICAL_DRIVES; j++)
-				if (megasas_mgmt_info.instance[i] &&
-				    (megasas_mgmt_info.instance[i] != instance) &&
-				    megasas_mgmt_info.instance[i]->mpio &&
-				    megasas_mgmt_info.instance[i]->requestorId
-				    &&
-				    (megasas_mgmt_info.instance[i]->ld_ids[j]
-				     == scmd->device->id)) {
-					    retval = (DID_NO_CONNECT << 16);
-					    goto out;
-				}
+	if (instance->peerIsPresent) {
+		peer_instance = megasas_get_peer_instance(instance);
+		if ((peer_instance) &&
+			(atomic_read(&peer_instance->adprecovery) ==
+			MEGASAS_HBA_OPERATIONAL))
+			retval = (DID_NO_CONNECT << 16);
 	}
-out:
 	return retval;
 }