samples/bpf: add xdp_redirect_pifo sample for testing PIFO mapxdp-queueing-02

Just a simple sample based on the old xdp_redirect_map sample, to exercise
the PIFO map for manual testing.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>

3 files changed, 272 insertions, 0 deletions

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 38638845db9d74..6a3fe16e77c0b1 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -57,6 +57,7 @@ tprogs-y += hbm
 tprogs-y += xdp_redirect_cpu
 tprogs-y += xdp_redirect_map_multi
 tprogs-y += xdp_redirect_map
+tprogs-y += xdp_redirect_pifo
 tprogs-y += xdp_redirect
 tprogs-y += xdp_monitor
 
@@ -181,6 +182,7 @@ always-y += ibumad_kern.o
 always-y += hbm_out_kern.o
 always-y += hbm_edt_kern.o
 always-y += xdpsock_kern.o
+always-y += xdp_redirect_pifo_kern.o
 
 ifeq ($(ARCH), arm)
 # Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
diff --git a/samples/bpf/xdp_redirect_pifo.c b/samples/bpf/xdp_redirect_pifo.c
new file mode 100644
index 00000000000000..3a90ce4789f8a6
--- /dev/null
+++ b/samples/bpf/xdp_redirect_pifo.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
+ */
+#include <linux/bpf.h>
+#include <linux/if_link.h>
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <libgen.h>
+#include <sys/resource.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include "bpf_util.h"
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+static int ifindex_in;
+static int ifindex_out;
+static bool ifindex_out_xdp_dummy_attached = true;
+static __u32 prog_id;
+
+static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+static int rxcnt_map_fd;
+
+static void int_exit(int sig)
+{
+	__u32 curr_prog_id = 0;
+
+	if (bpf_get_link_xdp_id(ifindex_in, &curr_prog_id, xdp_flags)) {
+		printf("bpf_get_link_xdp_id failed\n");
+		exit(1);
+	}
+	if (prog_id == curr_prog_id)
+		bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);
+	else if (!curr_prog_id)
+		printf("couldn't find a prog id on iface IN\n");
+	else
+		printf("program on iface IN changed, not removing\n");
+
+	if (ifindex_out_xdp_dummy_attached) {
+		curr_prog_id = 0;
+		if (bpf_get_link_xdp_id(ifindex_out, &curr_prog_id,
+					xdp_flags)) {
+			printf("bpf_get_link_xdp_id failed\n");
+			exit(1);
+		}
+		if (!curr_prog_id)
+			printf("couldn't find a prog id on iface OUT\n");
+		else
+			printf("program on iface OUT changed, not removing\n");
+	}
+	exit(0);
+}
+
+static void poll_stats(int interval, int ifindex)
+{
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	__u64 values[nr_cpus], prev[nr_cpus];
+
+	memset(prev, 0, sizeof(prev));
+
+	while (1) {
+		__u64 sum = 0;
+		__u32 key = 0;
+		int i;
+
+		sleep(interval);
+		assert(bpf_map_lookup_elem(rxcnt_map_fd, &key, values) == 0);
+		for (i = 0; i < nr_cpus; i++)
+			sum += (values[i] - prev[i]);
+		if (sum)
+			printf("ifindex %i: %10llu pkt/s\n",
+			       ifindex, sum / interval);
+		memcpy(prev, values, sizeof(values));
+	}
+}
+
+static void usage(const char *prog)
+{
+	fprintf(stderr,
+		"usage: %s [OPTS] <IFNAME|IFINDEX>_IN\n\n"
+		"OPTS:\n"
+		"    -N    enforce native mode\n"
+		"    -F    force loading prog\n",
+		prog);
+}
+
+int main(int argc, char **argv)
+{
+	struct bpf_prog_load_attr prog_load_attr = {
+		.prog_type	= BPF_PROG_TYPE_UNSPEC,
+	};
+	struct bpf_prog_info info = {};
+	__u32 info_len = sizeof(info);
+	int prog_fd, tx_mac_map_fd;
+	struct bpf_program *prog;
+	const char *optstr = "FN";
+	struct bpf_object *obj;
+	char filename[256];
+	int ret, opt;
+
+	while ((opt = getopt(argc, argv, optstr)) != -1) {
+		switch (opt) {
+		case 'N':
+			/* default, set below */
+			break;
+		case 'F':
+			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
+			break;
+		default:
+			usage(basename(argv[0]));
+			return 1;
+		}
+	}
+
+	if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) {
+		xdp_flags |= XDP_FLAGS_DRV_MODE;
+	}
+
+	if (optind == argc) {
+		printf("usage: %s <IFNAME|IFINDEX>_IN\n", argv[0]);
+		return 1;
+	}
+
+	ifindex_in = if_nametoindex(argv[optind]);
+	if (!ifindex_in)
+		ifindex_in = strtoul(argv[optind], NULL, 0);
+
+	printf("input: %d\n", ifindex_in);
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	prog_load_attr.file = filename;
+
+	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+		return 1;
+
+	prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_pifo");
+	prog_fd = bpf_program__fd(prog);
+	if (prog_fd < 0 ) {
+		printf("bpf_prog_load_xattr: %s\n", strerror(errno));
+		return 1;
+	}
+
+	tx_mac_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_mac");
+	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
+	if (tx_mac_map_fd < 0 || rxcnt_map_fd < 0) {
+		printf("bpf_object__find_map_fd_by_name failed\n");
+		return 1;
+	}
+
+	if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) {
+		printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);
+		return 1;
+	}
+
+	ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
+	if (ret) {
+		printf("can't get prog info - %s\n", strerror(errno));
+		return ret;
+	}
+	prog_id = info.id;
+
+	signal(SIGINT, int_exit);
+	signal(SIGTERM, int_exit);
+
+	poll_stats(2, ifindex_out);
+
+	return 0;
+}
diff --git a/samples/bpf/xdp_redirect_pifo_kern.c b/samples/bpf/xdp_redirect_pifo_kern.c
new file mode 100644
index 00000000000000..0de18304f241d0
--- /dev/null
+++ b/samples/bpf/xdp_redirect_pifo_kern.c
@@ -0,0 +1,92 @@
+/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#define KBUILD_MODNAME "foo"
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <bpf/bpf_helpers.h>
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PIFO);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(__u32));
+	__uint(max_entries, 1024);
+} pifo_map SEC(".maps");
+
+/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
+ * feedback.  Redirect TX errors can be caught via a tracepoint.
+ */
+struct {
+	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
+	__type(key, u32);
+	__type(value, long);
+	__uint(max_entries, 1);
+} rxcnt SEC(".maps");
+
+/* map to store egress interface mac address */
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__type(key, u32);
+	__type(value, __be64);
+	__uint(max_entries, 1);
+} tx_mac SEC(".maps");
+
+static void swap_src_dst_mac(void *data)
+{
+	unsigned short *p = data;
+	unsigned short dst[3];
+
+	dst[0] = p[0];
+	dst[1] = p[1];
+	dst[2] = p[2];
+	p[0] = p[3];
+	p[1] = p[4];
+	p[2] = p[5];
+	p[3] = dst[0];
+	p[4] = dst[1];
+	p[5] = dst[2];
+}
+
+SEC("xdp_redirect_pifo")
+int xdp_redirect_map_pifo(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	struct ethhdr *eth = data;
+	int rc = XDP_DROP;
+	long *value;
+	u32 key = 0;
+	u64 nh_off;
+	int vport;
+
+	nh_off = sizeof(*eth);
+	if (data + nh_off > data_end)
+		return rc;
+
+	/* constant virtual port */
+	vport = 0;
+
+	/* count packet in global counter */
+	value = bpf_map_lookup_elem(&rxcnt, &key);
+	if (value)
+		*value += 1;
+
+	swap_src_dst_mac(data);
+
+	/* send packet out physical port */
+	return bpf_redirect_map(&pifo_map, vport, 0);
+}
+
+char _license[] SEC("license") = "GPL";