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

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

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
Extension
.c
Size
14861 bytes
Lines
546
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

struct xsk {
	void *umem_area;
	struct xsk_umem *umem;
	struct xsk_ring_prod fill;
	struct xsk_ring_cons comp;
	struct xsk_ring_prod tx;
	struct xsk_ring_cons rx;
	struct xsk_socket *socket;
};

static int open_xsk(int ifindex, struct xsk *xsk)
{
	int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
	const struct xsk_socket_config socket_config = {
		.rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
		.tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
		.bind_flags = XDP_COPY,
	};
	const struct xsk_umem_config umem_config = {
		.fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
		.comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS,
		.frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE,
		.flags = XDP_UMEM_UNALIGNED_CHUNK_FLAG | XDP_UMEM_TX_SW_CSUM |
			 XDP_UMEM_TX_METADATA_LEN,
		.tx_metadata_len = sizeof(struct xsk_tx_metadata),
	};
	__u32 idx;
	u64 addr;
	int ret;
	int i;

	xsk->umem_area = mmap(NULL, UMEM_SIZE, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
	if (!ASSERT_NEQ(xsk->umem_area, MAP_FAILED, "mmap"))
		return -1;

	ret = xsk_umem__create(&xsk->umem,
			       xsk->umem_area, UMEM_SIZE,
			       &xsk->fill,
			       &xsk->comp,
			       &umem_config);
	if (!ASSERT_OK(ret, "xsk_umem__create"))
		return ret;

	ret = xsk_socket__create(&xsk->socket, ifindex, QUEUE_ID,
				 xsk->umem,
				 &xsk->rx,
				 &xsk->tx,
				 &socket_config);
	if (!ASSERT_OK(ret, "xsk_socket__create"))
		return ret;

	/* First half of umem is for TX. This way address matches 1-to-1
	 * to the completion queue index.
	 */

	for (i = 0; i < UMEM_NUM / 2; i++) {
		addr = i * UMEM_FRAME_SIZE;
		printf("%p: tx_desc[%d] -> %lx\n", xsk, i, addr);
	}

	/* Second half of umem is for RX. */

	ret = xsk_ring_prod__reserve(&xsk->fill, UMEM_NUM / 2, &idx);
	if (!ASSERT_EQ(UMEM_NUM / 2, ret, "xsk_ring_prod__reserve"))
		return ret;
	if (!ASSERT_EQ(idx, 0, "fill idx != 0"))
		return -1;

	for (i = 0; i < UMEM_NUM / 2; i++) {
		addr = (UMEM_NUM / 2 + i) * UMEM_FRAME_SIZE;
		printf("%p: rx_desc[%d] -> %lx\n", xsk, i, addr);
		*xsk_ring_prod__fill_addr(&xsk->fill, i) = addr;
	}
	xsk_ring_prod__submit(&xsk->fill, ret);

	return 0;
}

static void close_xsk(struct xsk *xsk)
{
	if (xsk->socket)
		xsk_socket__delete(xsk->socket);
	if (xsk->umem)
		xsk_umem__delete(xsk->umem);
	munmap(xsk->umem_area, UMEM_SIZE);
}

static int generate_packet(struct xsk *xsk, __u16 dst_port)
{
	struct xsk_tx_metadata *meta;

Annotation

Implementation Notes