tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c
Extension
.c
Size
5337 bytes
Lines
165
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <uapi/linux/bpf.h>
#include <linux/if_link.h>
#include <test_progs.h>
#include <network_helpers.h>

#include "test_xdp_with_cpumap_frags_helpers.skel.h"
#include "test_xdp_with_cpumap_helpers.skel.h"

#define IFINDEX_LO	1
#define TEST_NS "cpu_attach_ns"

static void test_xdp_with_cpumap_helpers(void)
{
	struct test_xdp_with_cpumap_helpers *skel = NULL;
	struct bpf_prog_info info = {};
	__u32 len = sizeof(info);
	struct bpf_cpumap_val val = {
		.qsize = 192,
	};
	int err, prog_fd, prog_redir_fd, map_fd, bad_fd;
	struct nstoken *nstoken = NULL;
	__u32 idx = 0;

	SYS(out_close, "ip netns add %s", TEST_NS);
	nstoken = open_netns(TEST_NS);
	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
		goto out_close;
	SYS(out_close, "ip link set dev lo up");

	skel = test_xdp_with_cpumap_helpers__open_and_load();
	if (!ASSERT_OK_PTR(skel, "test_xdp_with_cpumap_helpers__open_and_load"))
		return;

	prog_redir_fd = bpf_program__fd(skel->progs.xdp_redir_prog);
	err = bpf_xdp_attach(IFINDEX_LO, prog_redir_fd, XDP_FLAGS_SKB_MODE, NULL);
	if (!ASSERT_OK(err, "Generic attach of program with 8-byte CPUMAP"))
		goto out_close;

	prog_fd = bpf_program__fd(skel->progs.xdp_dummy_cm);
	map_fd = bpf_map__fd(skel->maps.cpu_map);
	err = bpf_prog_get_info_by_fd(prog_fd, &info, &len);
	if (!ASSERT_OK(err, "bpf_prog_get_info_by_fd"))
		goto out_close;

	val.bpf_prog.fd = prog_fd;
	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
	ASSERT_OK(err, "Add program to cpumap entry");

	err = bpf_map_lookup_elem(map_fd, &idx, &val);
	ASSERT_OK(err, "Read cpumap entry");
	ASSERT_EQ(info.id, val.bpf_prog.id, "Match program id to cpumap entry prog_id");

	/* send a packet to trigger any potential bugs in there */
	char data[ETH_HLEN] = {};
	DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts,
			    .data_in = &data,
			    .data_size_in = sizeof(data),
			    .flags = BPF_F_TEST_XDP_LIVE_FRAMES,
			    .repeat = 1,
		);
	err = bpf_prog_test_run_opts(prog_redir_fd, &opts);
	ASSERT_OK(err, "XDP test run");

	/* wait for the packets to be flushed, then check that redirect has been
	 * performed
	 */
	kern_sync_rcu();
	ASSERT_NEQ(skel->bss->redirect_count, 0, "redirected packets");

	err = bpf_xdp_detach(IFINDEX_LO, XDP_FLAGS_SKB_MODE, NULL);
	ASSERT_OK(err, "XDP program detach");

	/* can not attach BPF_XDP_CPUMAP program to a device */
	err = bpf_xdp_attach(IFINDEX_LO, prog_fd, XDP_FLAGS_SKB_MODE, NULL);
	if (!ASSERT_NEQ(err, 0, "Attach of BPF_XDP_CPUMAP program"))
		bpf_xdp_detach(IFINDEX_LO, XDP_FLAGS_SKB_MODE, NULL);

	val.qsize = 192;
	val.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_dummy_prog);
	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
	ASSERT_EQ(err, -EINVAL, "Add non-BPF_XDP_CPUMAP program to cpumap entry");

	/* Try to attach non-BPF file descriptor */
	bad_fd = open("/dev/null", O_RDONLY);
	ASSERT_GE(bad_fd, 0, "Open /dev/null for non-BPF fd");

	val.bpf_prog.fd = bad_fd;
	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
	ASSERT_EQ(err, -EINVAL, "Add non-BPF fd to cpumap entry");

Annotation

Implementation Notes