1 files changed, 49 insertions, 0 deletions
diff --git a/lib/libxdp/xsk_def_xdp_prog_5.3.c b/lib/libxdp/xsk_def_xdp_prog_5.3.c
new file mode 100644
index 0000000..7973477
--- /dev/null
+++ b/lib/libxdp/xsk_def_xdp_prog_5.3.c
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <xdp/xdp_helpers.h>
+
+#include "xsk_def_xdp_prog.h"
+
+#define DEFAULT_QUEUE_IDS 64
+
+struct {
+	__uint(type, BPF_MAP_TYPE_XSKMAP);
+	__uint(key_size, sizeof(int));
+	__uint(value_size, sizeof(int));
+	__uint(max_entries, DEFAULT_QUEUE_IDS);
+} xsks_map SEC(".maps");
+
+struct {
+	__uint(priority, 20);
+	__uint(XDP_PASS, 1);
+} XDP_RUN_CONFIG(xsk_def_prog);
+
+/* Program refcount, in order to work properly,
+ * must be declared before any other global variables
+ * and initialized with '1'.
+ */
+volatile int refcnt = 1;
+
+/* This is the program for 5.3 kernels and older. */
+SEC("xdp")
+int xsk_def_prog(struct xdp_md *ctx)
+{
+	int index = ctx->rx_queue_index;
+
+	/* Make sure refcount is referenced by the program */
+	if (!refcnt)
+		return XDP_PASS;
+
+	/* A set entry here means that the corresponding queue_id
+	 * has an active AF_XDP socket bound to it.
+	 */
+	if (bpf_map_lookup_elem(&xsks_map, &index))
+		return bpf_redirect_map(&xsks_map, index, 0);
+	return XDP_PASS;
+
+}
+
+char _license[] SEC("license") = "GPL";
+__uint(xsk_prog_version, XSK_PROG_VERSION) SEC(XDP_METADATA_SECTION);