From ea5c3a2ffa0b7f4e720457821bfdd594516744d1 Mon Sep 17 00:00:00 2001

From: Andrea Claudi <aclaudi@redhat.com>

Date: Tue, 21 Apr 2020 14:32:49 +0200

Subject: [PATCH] tc: Add support for the CBS qdisc

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1557461

Upstream Status: iproute2.git commit c9681ac1b3e0c

commit c9681ac1b3e0cd7b8e8b8cba17ac7090775ca647

Author: Vinicius Costa Gomes <vinicius.gomes@intel.com>

Date:   Thu Oct 26 10:17:48 2017 -0700

    tc: Add support for the CBS qdisc

    The Credit Based Shaper (CBS) queueing discipline allows bandwidth

    reservation with sub-milisecond precision. It is defined by the

    802.1Q-2014 specification (section 8.6.8.2 and Annex L).

    The syntax is:

    tc qdisc add dev DEV parent NODE cbs locredit <LOCREDIT>

                    hicredit <HICREDIT> sendslope <SENDSLOPE>

                    idleslope <IDLESLOPE>

    (The order is not important)

    Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>

    Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

---

 tc/Makefile |   1 +

 tc/q_cbs.c  | 142 ++++++++++++++++++++++++++++++++++++++++++++++++++++

 2 files changed, 143 insertions(+)

 create mode 100644 tc/q_cbs.c

diff --git a/tc/Makefile b/tc/Makefile

index 9a6bb1ddea57e..6b4e5f2b20762 100644

--- a/tc/Makefile

+++ b/tc/Makefile

@@ -72,6 +72,7 @@ TCMODULES += q_hhf.o

 TCMODULES += q_clsact.o

 TCMODULES += e_bpf.o

 TCMODULES += f_matchall.o

+TCMODULES += q_cbs.o

 TCSO :=

 ifeq ($(TC_CONFIG_ATM),y)

diff --git a/tc/q_cbs.c b/tc/q_cbs.c

new file mode 100644

index 0000000000000..e53be6548ad9a

--- /dev/null

+++ b/tc/q_cbs.c

@@ -0,0 +1,142 @@

+/*

+ * q_cbs.c		CBS.

+ *

+ *		This program is free software; you can redistribute it and/or

+ *		modify it under the terms of the GNU General Public License

+ *		as published by the Free Software Foundation; either version

+ *		2 of the License, or (at your option) any later version.

+ *

+ * Authors:	Vinicius Costa Gomes <vinicius.gomes@intel.com>

+ *

+ */

+

+#include <stdio.h>

+#include <stdlib.h>

+#include <unistd.h>

+#include <syslog.h>

+#include <fcntl.h>

+#include <sys/socket.h>

+#include <netinet/in.h>

+#include <arpa/inet.h>

+#include <string.h>

+

+#include "utils.h"

+#include "tc_util.h"

+

+static void explain(void)

+{

+	fprintf(stderr, "Usage: ... cbs hicredit BYTES locredit BYTES sendslope BPS idleslope BPS\n");

+	fprintf(stderr, "           [offload 0|1]\n");

+

+}

+

+static void explain1(const char *arg, const char *val)

+{

+	fprintf(stderr, "cbs: illegal value for \"%s\": \"%s\"\n", arg, val);

+}

+

+static int cbs_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)

+{

+	struct tc_cbs_qopt opt = {};

+	struct rtattr *tail;

+

+	while (argc > 0) {

+		if (matches(*argv, "offload") == 0) {

+			NEXT_ARG();

+			if (opt.offload) {

+				fprintf(stderr, "cbs: duplicate \"offload\" specification\n");

+				return -1;

+			}

+			if (get_u8(&opt.offload, *argv, 0)) {

+				explain1("offload", *argv);

+				return -1;

+			}

+		} else if (matches(*argv, "hicredit") == 0) {

+			NEXT_ARG();

+			if (opt.hicredit) {

+				fprintf(stderr, "cbs: duplicate \"hicredit\" specification\n");

+				return -1;

+			}

+			if (get_s32(&opt.hicredit, *argv, 0)) {

+				explain1("hicredit", *argv);

+				return -1;

+			}

+		} else if (matches(*argv, "locredit") == 0) {

+			NEXT_ARG();

+			if (opt.locredit) {

+				fprintf(stderr, "cbs: duplicate \"locredit\" specification\n");

+				return -1;

+			}

+			if (get_s32(&opt.locredit, *argv, 0)) {

+				explain1("locredit", *argv);

+				return -1;

+			}

+		} else if (matches(*argv, "sendslope") == 0) {

+			NEXT_ARG();

+			if (opt.sendslope) {

+				fprintf(stderr, "cbs: duplicate \"sendslope\" specification\n");

+				return -1;

+			}

+			if (get_s32(&opt.sendslope, *argv, 0)) {

+				explain1("sendslope", *argv);

+				return -1;

+			}

+		} else if (matches(*argv, "idleslope") == 0) {

+			NEXT_ARG();

+			if (opt.idleslope) {

+				fprintf(stderr, "cbs: duplicate \"idleslope\" specification\n");

+				return -1;

+			}

+			if (get_s32(&opt.idleslope, *argv, 0)) {

+				explain1("idleslope", *argv);

+				return -1;

+			}

+		} else if (strcmp(*argv, "help") == 0) {

+			explain();

+			return -1;

+		} else {

+			fprintf(stderr, "cbs: unknown parameter \"%s\"\n", *argv);

+			explain();

+			return -1;

+		}

+		argc--; argv++;

+	}

+

+	tail = NLMSG_TAIL(n);

+	addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);

+	addattr_l(n, 2024, TCA_CBS_PARMS, &opt, sizeof(opt));

+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;

+	return 0;

+}

+

+static int cbs_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)

+{

+	struct rtattr *tb[TCA_CBS_MAX+1];

+	struct tc_cbs_qopt *qopt;

+

+	if (opt == NULL)

+		return 0;

+

+	parse_rtattr_nested(tb, TCA_CBS_MAX, opt);

+

+	if (tb[TCA_CBS_PARMS] == NULL)

+		return -1;

+

+	qopt = RTA_DATA(tb[TCA_CBS_PARMS]);

+	if (RTA_PAYLOAD(tb[TCA_CBS_PARMS])  < sizeof(*qopt))

+		return -1;

+

+	fprintf(f, "hicredit %d ", qopt->hicredit);

+	fprintf(f, "locredit %d ", qopt->locredit);

+	fprintf(f, "sendslope %d ", qopt->sendslope);

+	fprintf(f, "idleslope %d ", qopt->idleslope);

+	fprintf(f, "offload %d ", qopt->offload);

+

+	return 0;

+}

+

+struct qdisc_util cbs_qdisc_util = {

+	.id		= "cbs",

+	.parse_qopt	= cbs_parse_opt,

+	.print_qopt	= cbs_print_opt,

+};

-- 

2.25.3