xdp: add flag to enforce driver mode

After commit b5cdae3291f7 ("net: Generic XDP") we automatically fall
back to a generic XDP variant if the driver does not support native
XDP. Allow for an option where the user can specify that always the
native XDP variant should be selected and in case it's not supported
by a driver, just bail out.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 12 insertions, 3 deletions

diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index 378850c70eb8..17be9ea3ecb2 100644
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -62,13 +62,14 @@ static void usage(const char *prog)
         fprintf(stderr,
                 "usage: %s [OPTS] IFINDEX\n\n"
                 "OPTS:\n"
-                "    -S    use skb-mode\n",
+                "    -S    use skb-mode\n"
+                "    -N    enforce native mode\n",
                 prog);
 }
 
 int main(int argc, char **argv)
 {
-        const char *optstr = "S";
+        const char *optstr = "SN";
         char filename[256];
         int opt;
 
@@ -77,6 +78,9 @@ int main(int argc, char **argv)
                 case 'S':
                         xdp_flags |= XDP_FLAGS_SKB_MODE;
                         break;
+                case 'N':
+                        xdp_flags |= XDP_FLAGS_DRV_MODE;
+                        break;
                 default:
                         usage(basename(argv[0]));
                         return 1;
diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index 92b8bde9337c..631cdcc41c97 100644
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -79,6 +79,8 @@ static void usage(const char *cmd)
         printf("    -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
         printf("    -T <stop-after-X-seconds> Default: 0 (forever)\n");
         printf("    -P <IP-Protocol> Default is TCP\n");
+        printf("    -S use skb-mode\n");
+        printf("    -N enforce native mode\n");
         printf("    -h Display this help\n");
 }
 
@@ -138,7 +140,7 @@ int main(int argc, char **argv)
 {
         unsigned char opt_flags[256] = {};
         unsigned int kill_after_s = 0;
-        const char *optstr = "i:a:p:s:d:m:T:P:Sh";
+        const char *optstr = "i:a:p:s:d:m:T:P:SNh";
         int min_port = 0, max_port = 0;
         struct iptnl_info tnl = {};
         struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
@@ -206,6 +208,9 @@ int main(int argc, char **argv)
                 case 'S':
                         xdp_flags |= XDP_FLAGS_SKB_MODE;
                         break;
+                case 'N':
+                        xdp_flags |= XDP_FLAGS_DRV_MODE;
+                        break;
                 default:
                         usage(argv[0]);
                         return 1;