nvme: consider also host_iface when checking ip options

It's perfectly fine to use the same traddr and trsvcid more than once
as long we use different host interface. This is used in setups where
the host has more than one interface but the target exposes only one
traddr/trsvcid combination.

Use the same acceptance rules for host_iface as we have for
host_traddr.
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/fabrics.c

@@ -971,13 +971,17 @@ bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
 		return false;
 
 	/*
-	 * Checking the local address is rough. In most cases, none is specified
-	 * and the host port is selected by the stack.
+	 * Checking the local address or host interfaces is rough.
+	 *
+	 * In most cases, none is specified and the host port or
+	 * host interface is selected by the stack.
 	 *
 	 * Assume no match if:
-	 * -  local address is specified and address is not the same
-	 * -  local address is not specified but remote is, or vice versa
-	 *    (admin using specific host_traddr when it matters).
+	 * -  local address or host interface is specified and address
+	 *    or host interface is not the same
+	 * -  local address or host interface is not specified but
+	 *    remote is, or vice versa (admin using specific
+	 *    host_traddr/host_iface when it matters).
 	 */
 	if ((opts->mask & NVMF_OPT_HOST_TRADDR) &&
 	    (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)) {
@@ -988,6 +992,15 @@ bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
 		return false;
 	}
 
+	if ((opts->mask & NVMF_OPT_HOST_IFACE) &&
+	    (ctrl->opts->mask & NVMF_OPT_HOST_IFACE)) {
+		if (strcmp(opts->host_iface, ctrl->opts->host_iface))
+			return false;
+	} else if ((opts->mask & NVMF_OPT_HOST_IFACE) ||
+		   (ctrl->opts->mask & NVMF_OPT_HOST_IFACE)) {
+		return false;
+	}
+
 	return true;
 }
 EXPORT_SYMBOL_GPL(nvmf_ip_options_match);