[PATCH] ip link: hsr: Add support for passing information about INTERLINK device

[Lukasz Majewski <lukma@denx.de>]

The HSR capable device can operate in two modes of operations -
Doubly Attached Node for HSR (DANH) and RedBOX.

The latter one allows connection of non-HSR aware device to HSR network.
This node is called SAN (Singly Attached Network) and is connected via
INTERLINK network device.

This patch adds support for passing information about the INTERLINK device,
so the Linux driver can properly setup it.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
---
 include/uapi/linux/if_link.h |  1 +
 ip/iplink_hsr.c              | 22 +++++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 41708e2..aa70ed6 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -1122,6 +1122,7 @@ enum {
 	IFLA_HSR_PROTOCOL,		/* Indicate different protocol than
 					 * HSR. For example PRP.
 					 */
+	IFLA_HSR_INTERLINK,		/* HSR interlink network device */
 	__IFLA_HSR_MAX,
 };
 
diff --git a/ip/iplink_hsr.c b/ip/iplink_hsr.c
index da2d03d..1f048fd 100644
--- a/ip/iplink_hsr.c
+++ b/ip/iplink_hsr.c
@@ -25,12 +25,15 @@ static void print_usage(FILE *f)
 {
 	fprintf(f,
 		"Usage:\tip link add name NAME type hsr slave1 SLAVE1-IF slave2 SLAVE2-IF\n"
-		"\t[ supervision ADDR-BYTE ] [version VERSION] [proto PROTOCOL]\n"
+		"\t[ interlink INTERLINK-IF ] [ supervision ADDR-BYTE ] [ version VERSION ]\n"
+		"\t[ proto PROTOCOL ]\n"
 		"\n"
 		"NAME\n"
 		"	name of new hsr device (e.g. hsr0)\n"
 		"SLAVE1-IF, SLAVE2-IF\n"
 		"	the two slave devices bound to the HSR device\n"
+		"INTERLINK-IF\n"
+		"	the interlink device bound to the HSR network to connect SAN device\n"
 		"ADDR-BYTE\n"
 		"	0-255; the last byte of the multicast address used for HSR supervision\n"
 		"	frames (default = 0)\n"
@@ -86,6 +89,12 @@ static int hsr_parse_opt(struct link_util *lu, int argc, char **argv,
 			if (ifindex == 0)
 				invarg("No such interface", *argv);
 			addattr_l(n, 1024, IFLA_HSR_SLAVE2, &ifindex, 4);
+		} else if (matches(*argv, "interlink") == 0) {
+			NEXT_ARG();
+			ifindex = ll_name_to_index(*argv);
+			if (ifindex == 0)
+				invarg("No such interface", *argv);
+			addattr_l(n, 1024, IFLA_HSR_INTERLINK, &ifindex, 4);
 		} else if (matches(*argv, "help") == 0) {
 			usage();
 			return -1;
@@ -113,6 +122,9 @@ static void hsr_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 	if (tb[IFLA_HSR_SLAVE2] &&
 	    RTA_PAYLOAD(tb[IFLA_HSR_SLAVE2]) < sizeof(__u32))
 		return;
+	if (tb[IFLA_HSR_INTERLINK] &&
+	    RTA_PAYLOAD(tb[IFLA_HSR_INTERLINK]) < sizeof(__u32))
+		return;
 	if (tb[IFLA_HSR_SEQ_NR] &&
 	    RTA_PAYLOAD(tb[IFLA_HSR_SEQ_NR]) < sizeof(__u16))
 		return;
@@ -136,6 +148,14 @@ static void hsr_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 	else
 		print_null(PRINT_ANY, "slave2", "slave2 %s ", "<none>");
 
+	if (tb[IFLA_HSR_INTERLINK])
+		print_string(PRINT_ANY,
+			     "interlink",
+			     "interlink %s ",
+			     ll_index_to_name(rta_getattr_u32(tb[IFLA_HSR_INTERLINK])));
+	else
+		print_null(PRINT_ANY, "interlink", "interlink %s ", "<none>");
+
 	if (tb[IFLA_HSR_SEQ_NR])
 		print_int(PRINT_ANY,
 			  "seq_nr",
-- 
2.20.1