bnx2x: handle known but unsupported VF messages

Commit b9871bc "bnx2x: VF RSS support - PF side" has deprecated one of
the previous existing messages. If an old VF driver were to send this message
to the PF then the PF will not reply and leave the mailbox in an unsteady
state (and cause a timeout on the VF side).

Wait until firmware ack is written before unlocking channel

Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c

@@ -1765,28 +1765,28 @@ static void bnx2x_vf_mbx_request(struct bnx2x *bp, struct bnx2x_virtf *vf,
 		switch (mbx->first_tlv.tl.type) {
 		case CHANNEL_TLV_ACQUIRE:
 			bnx2x_vf_mbx_acquire(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_INIT:
 			bnx2x_vf_mbx_init_vf(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_SETUP_Q:
 			bnx2x_vf_mbx_setup_q(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_SET_Q_FILTERS:
 			bnx2x_vf_mbx_set_q_filters(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_TEARDOWN_Q:
 			bnx2x_vf_mbx_teardown_q(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_CLOSE:
 			bnx2x_vf_mbx_close_vf(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_RELEASE:
 			bnx2x_vf_mbx_release_vf(bp, vf, mbx);
-			break;
+			return;
 		case CHANNEL_TLV_UPDATE_RSS:
 			bnx2x_vf_mbx_update_rss(bp, vf, mbx);
-			break;
+			return;
 		}
 
 	} else {
@@ -1802,26 +1802,24 @@ static void bnx2x_vf_mbx_request(struct bnx2x *bp, struct bnx2x_virtf *vf,
 		for (i = 0; i < 20; i++)
 			DP_CONT(BNX2X_MSG_IOV, "%x ",
 				mbx->msg->req.tlv_buf_size.tlv_buffer[i]);
+	}
 
-		/* test whether we can respond to the VF (do we have an address
-		 * for it?)
-		 */
-		if (vf->state == VF_ACQUIRED || vf->state == VF_ENABLED) {
-			/* mbx_resp uses the op_rc of the VF */
-			vf->op_rc = PFVF_STATUS_NOT_SUPPORTED;
+	/* can we respond to VF (do we have an address for it?) */
+	if (vf->state == VF_ACQUIRED || vf->state == VF_ENABLED) {
+		/* mbx_resp uses the op_rc of the VF */
+		vf->op_rc = PFVF_STATUS_NOT_SUPPORTED;
 
-			/* notify the VF that we do not support this request */
-			bnx2x_vf_mbx_resp(bp, vf);
-		} else {
-			/* can't send a response since this VF is unknown to us
-			 * just ack the FW to release the mailbox and unlock
-			 * the channel.
-			 */
-			storm_memset_vf_mbx_ack(bp, vf->abs_vfid);
-			mmiowb();
-			bnx2x_unlock_vf_pf_channel(bp, vf,
-						   mbx->first_tlv.tl.type);
-		}
+		/* notify the VF that we do not support this request */
+		bnx2x_vf_mbx_resp(bp, vf);
+	} else {
+		/* can't send a response since this VF is unknown to us
+		 * just ack the FW to release the mailbox and unlock
+		 * the channel.
+		 */
+		storm_memset_vf_mbx_ack(bp, vf->abs_vfid);
+		/* Firmware ack should be written before unlocking channel */
+		mmiowb();
+		bnx2x_unlock_vf_pf_channel(bp, vf, mbx->first_tlv.tl.type);
 	}
 }