1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <vmlinux.h>
4 #include "xdp_metadata.h"
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_endian.h>
7
8 struct {
9 __uint(type, BPF_MAP_TYPE_XSKMAP);
10 __uint(max_entries, 4);
11 __type(key, __u32);
12 __type(value, __u32);
13 } xsk SEC(".maps");
14
15 struct {
16 __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
17 __uint(max_entries, 1);
18 __type(key, __u32);
19 __type(value, __u32);
20 } prog_arr SEC(".maps");
21
22 extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
23 __u64 *timestamp) __ksym;
24 extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
25 __u32 *hash) __ksym;
26
27 SEC("xdp")
rx(struct xdp_md * ctx)28 int rx(struct xdp_md *ctx)
29 {
30 void *data, *data_meta;
31 struct xdp_meta *meta;
32 u64 timestamp = -1;
33 int ret;
34
35 /* Reserve enough for all custom metadata. */
36
37 ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
38 if (ret != 0)
39 return XDP_DROP;
40
41 data = (void *)(long)ctx->data;
42 data_meta = (void *)(long)ctx->data_meta;
43
44 if (data_meta + sizeof(struct xdp_meta) > data)
45 return XDP_DROP;
46
47 meta = data_meta;
48
49 /* Export metadata. */
50
51 /* We expect veth bpf_xdp_metadata_rx_timestamp to return 0 HW
52 * timestamp, so put some non-zero value into AF_XDP frame for
53 * the userspace.
54 */
55 bpf_xdp_metadata_rx_timestamp(ctx, ×tamp);
56 if (timestamp == 0)
57 meta->rx_timestamp = 1;
58
59 bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash);
60
61 return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
62 }
63
64 char _license[] SEC("license") = "GPL";
65