selftests/bpf: Add test for bpf_get_link_xdp_id

// SPDX-License-Identifier: GPL-2.0

#include <linux/if_link.h>

#include <test_progs.h>

#define IFINDEX_LO 1

void test_xdp_info(void)

{

	__u32 len = sizeof(struct bpf_prog_info), duration = 0, prog_id;

	const char *file = "./xdp_dummy.o";

	struct bpf_prog_info info = {};

	struct bpf_object *obj;

	int err, prog_fd;

	/* Get prog_id for XDP_ATTACHED_NONE mode */

	err = bpf_get_link_xdp_id(IFINDEX_LO, &prog_id, 0);

	if (CHECK(err, "get_xdp_none", "errno=%d\n", errno))

		return;

	if (CHECK(prog_id, "prog_id_none", "unexpected prog_id=%u\n", prog_id))

		return;

	err = bpf_get_link_xdp_id(IFINDEX_LO, &prog_id, XDP_FLAGS_SKB_MODE);

	if (CHECK(err, "get_xdp_none_skb", "errno=%d\n", errno))

		return;

	if (CHECK(prog_id, "prog_id_none_skb", "unexpected prog_id=%u\n",

		  prog_id))

		return;

	/* Setup prog */

	err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);

	if (CHECK_FAIL(err))

		return;

	err = bpf_obj_get_info_by_fd(prog_fd, &info, &len);

	if (CHECK(err, "get_prog_info", "errno=%d\n", errno))

		goto out_close;

	err = bpf_set_link_xdp_fd(IFINDEX_LO, prog_fd, XDP_FLAGS_SKB_MODE);

	if (CHECK(err, "set_xdp_skb", "errno=%d\n", errno))

		goto out_close;

	/* Get prog_id for single prog mode */

	err = bpf_get_link_xdp_id(IFINDEX_LO, &prog_id, 0);

	if (CHECK(err, "get_xdp", "errno=%d\n", errno))

		goto out;

	if (CHECK(prog_id != info.id, "prog_id", "prog_id not available\n"))

		goto out;

	err = bpf_get_link_xdp_id(IFINDEX_LO, &prog_id, XDP_FLAGS_SKB_MODE);

	if (CHECK(err, "get_xdp_skb", "errno=%d\n", errno))

		goto out;

	if (CHECK(prog_id != info.id, "prog_id_skb", "prog_id not available\n"))

		goto out;

	err = bpf_get_link_xdp_id(IFINDEX_LO, &prog_id, XDP_FLAGS_DRV_MODE);

	if (CHECK(err, "get_xdp_drv", "errno=%d\n", errno))

		goto out;

	if (CHECK(prog_id, "prog_id_drv", "unexpected prog_id=%u\n", prog_id))

		goto out;

out:

	bpf_set_link_xdp_fd(IFINDEX_LO, -1, 0);

out_close:

	bpf_object__close(obj);

}