samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel

Add option to xdp1 and xdp_tx_iptunnel to insert xdp program in
SKB_MODE:
 - update set_link_xdp_fd to take a flags argument that is added to the
   RTM_SETLINK message

 - Add -S option to xdp1 and xdp_tx_iptunnel user code. When passed in
   XDP_FLAGS_SKB_MODE is set in the flags arg passed to set_link_xdp_fd

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 32 insertions, 8 deletions

diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index d2be65d1fd86..deb05e630d84 100644
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -5,6 +5,7 @@
  * License as published by the Free Software Foundation.
  */
 #include <linux/bpf.h>
+#include <linux/if_link.h>
 #include <assert.h>
 #include <errno.h>
 #include <signal.h>
@@ -12,16 +13,18 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <libgen.h>
 
 #include "bpf_load.h"
 #include "bpf_util.h"
 #include "libbpf.h"
 
 static int ifindex;
+static int flags;
 
 static void int_exit(int sig)
 {
-	set_link_xdp_fd(ifindex, -1);
+	set_link_xdp_fd(ifindex, -1, flags);
 	exit(0);
 }
 
@@ -54,18 +57,39 @@ static void poll_stats(int interval)
 	}
 }
 
-int main(int ac, char **argv)
+static void usage(const char *prog)
 {
-	char filename[256];
+	fprintf(stderr,
+		"usage: %s [OPTS] IFINDEX\n\n"
+		"OPTS:\n"
+		"    -S    use skb-mode\n",
+		prog);
+}
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+int main(int argc, char **argv)
+{
+	const char *optstr = "S";
+	char filename[256];
+	int opt;
+
+	while ((opt = getopt(argc, argv, optstr)) != -1) {
+		switch (opt) {
+		case 'S':
+			flags |= XDP_FLAGS_SKB_MODE;
+			break;
+		default:
+			usage(basename(argv[0]));
+			return 1;
+		}
+	}
 
-	if (ac != 2) {
-		printf("usage: %s IFINDEX\n", argv[0]);
+	if (optind == argc) {
+		usage(basename(argv[0]));
 		return 1;
 	}
+	ifindex = strtoul(argv[optind], NULL, 0);
 
-	ifindex = strtoul(argv[1], NULL, 0);
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 
 	if (load_bpf_file(filename)) {
 		printf("%s", bpf_log_buf);
@@ -79,7 +103,7 @@ int main(int ac, char **argv)
 
 	signal(SIGINT, int_exit);
 
-	if (set_link_xdp_fd(ifindex, prog_fd[0]) < 0) {
+	if (set_link_xdp_fd(ifindex, prog_fd[0], flags) < 0) {
 		printf("link set xdp fd failed\n");
 		return 1;
 	}