[SCSI] libfcoe: Support extra MAC descriptor to be used as FCoE MAC

Some switch implementations (eg., HP virtual connect FlexFabric) send two MAC
descriptors in FIP FLOGI response, with first MAC descriptor (granted_mac) used
as FPMA, and the second one (fcoe_mac) used as destination address for
sending/receiving FCoE packets. fip_mac continues to be used for FIP traffic.
This patch introduces fcoe_mac in fcoe_fcf structure. For regular switches,
both fcoe_mac and fip_mac will be the same. For the switches that send
additional MAC descriptor, fcoe_mac is updated.

Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/fcoe/fcoe_ctlr.c

@@ -242,7 +242,7 @@ static void fcoe_ctlr_announce(struct fcoe_ctlr *fip)
 		printk(KERN_INFO "libfcoe: host%d: FIP selected "
 		       "Fibre-Channel Forwarder MAC %pM\n",
 		       fip->lp->host->host_no, sel->fcf_mac);
-		memcpy(fip->dest_addr, sel->fcf_mac, ETH_ALEN);
+		memcpy(fip->dest_addr, sel->fcoe_mac, ETH_ALEN);
 		fip->map_dest = 0;
 	}
 unlock:
@@ -824,6 +824,7 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
 			memcpy(fcf->fcf_mac,
 			       ((struct fip_mac_desc *)desc)->fd_mac,
 			       ETH_ALEN);
+			memcpy(fcf->fcoe_mac, fcf->fcf_mac, ETH_ALEN);
 			if (!is_valid_ether_addr(fcf->fcf_mac)) {
 				LIBFCOE_FIP_DBG(fip,
 					"Invalid MAC addr %pM in FIP adv\n",
@@ -1013,6 +1014,7 @@ static void fcoe_ctlr_recv_els(struct fcoe_ctlr *fip, struct sk_buff *skb)
 	struct fip_desc *desc;
 	struct fip_encaps *els;
 	struct fcoe_dev_stats *stats;
+	struct fcoe_fcf *sel;
 	enum fip_desc_type els_dtype = 0;
 	u8 els_op;
 	u8 sub;
@@ -1040,7 +1042,8 @@ static void fcoe_ctlr_recv_els(struct fcoe_ctlr *fip, struct sk_buff *skb)
 			goto drop;
 		/* Drop ELS if there are duplicate critical descriptors */
 		if (desc->fip_dtype < 32) {
-			if (desc_mask & 1U << desc->fip_dtype) {
+			if ((desc->fip_dtype != FIP_DT_MAC) &&
+			    (desc_mask & 1U << desc->fip_dtype)) {
 				LIBFCOE_FIP_DBG(fip, "Duplicate Critical "
 						"Descriptors in FIP ELS\n");
 				goto drop;
@@ -1049,17 +1052,32 @@ static void fcoe_ctlr_recv_els(struct fcoe_ctlr *fip, struct sk_buff *skb)
 		}
 		switch (desc->fip_dtype) {
 		case FIP_DT_MAC:
+			sel = fip->sel_fcf;
 			if (desc_cnt == 1) {
 				LIBFCOE_FIP_DBG(fip, "FIP descriptors "
 						"received out of order\n");
 				goto drop;
 			}
+			/*
+			 * Some switch implementations send two MAC descriptors,
+			 * with first MAC(granted_mac) being the FPMA, and the
+			 * second one(fcoe_mac) is used as destination address
+			 * for sending/receiving FCoE packets. FIP traffic is
+			 * sent using fip_mac. For regular switches, both
+			 * fip_mac and fcoe_mac would be the same.
+			 */
+			if (desc_cnt == 2)
+				memcpy(granted_mac,
+				       ((struct fip_mac_desc *)desc)->fd_mac,
+				       ETH_ALEN);
 
 			if (dlen != sizeof(struct fip_mac_desc))
 				goto len_err;
-			memcpy(granted_mac,
-			       ((struct fip_mac_desc *)desc)->fd_mac,
-			       ETH_ALEN);
+
+			if ((desc_cnt == 3) && (sel))
+				memcpy(sel->fcoe_mac,
+				       ((struct fip_mac_desc *)desc)->fd_mac,
+				       ETH_ALEN);
 			break;
 		case FIP_DT_FLOGI:
 		case FIP_DT_FDISC:

include/scsi/libfcoe.h

@@ -165,7 +165,8 @@ struct fcoe_ctlr {
  * @switch_name: WWN of switch from advertisement
  * @fabric_name: WWN of fabric from advertisement
  * @fc_map:	 FC_MAP value from advertisement
- * @fcf_mac:	 Ethernet address of the FCF
+ * @fcf_mac:	 Ethernet address of the FCF for FIP traffic
+ * @fcoe_mac:	 Ethernet address of the FCF for FCoE traffic
  * @vfid:	 virtual fabric ID
  * @pri:	 selection priority, smaller values are better
  * @flogi_sent:	 current FLOGI sent to this FCF
@@ -188,6 +189,7 @@ struct fcoe_fcf {
 	u32 fc_map;
 	u16 vfid;
 	u8 fcf_mac[ETH_ALEN];
+	u8 fcoe_mac[ETH_ALEN];
 
 	u8 pri;
 	u8 flogi_sent;