tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c- Extension
.c- Size
- 4030 bytes
- Lines
- 147
- 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.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
test_progs.hnetwork_helpers.h
Detected Declarations
function test_xdp_update_fragsfunction test_xdp_adjust_frags
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include <network_helpers.h>
static void test_xdp_update_frags(void)
{
const char *file = "./test_xdp_update_frags.bpf.o";
int err, prog_fd, max_skb_frags, buf_size, num;
struct bpf_program *prog;
struct bpf_object *obj;
__u32 *offset;
__u8 *buf;
FILE *f;
LIBBPF_OPTS(bpf_test_run_opts, topts);
obj = bpf_object__open(file);
if (libbpf_get_error(obj))
return;
prog = bpf_object__next_program(obj, NULL);
if (bpf_object__load(obj))
return;
prog_fd = bpf_program__fd(prog);
buf = malloc(128);
if (!ASSERT_OK_PTR(buf, "alloc buf 128b"))
goto out;
memset(buf, 0, 128);
offset = (__u32 *)buf;
*offset = 16;
buf[*offset] = 0xaa; /* marker at offset 16 (head) */
buf[*offset + 15] = 0xaa; /* marker at offset 31 (head) */
topts.data_in = buf;
topts.data_out = buf;
topts.data_size_in = 128;
topts.data_size_out = 128;
err = bpf_prog_test_run_opts(prog_fd, &topts);
/* test_xdp_update_frags: buf[16,31]: 0xaa -> 0xbb */
ASSERT_OK(err, "xdp_update_frag");
ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
ASSERT_EQ(buf[16], 0xbb, "xdp_update_frag buf[16]");
ASSERT_EQ(buf[31], 0xbb, "xdp_update_frag buf[31]");
free(buf);
buf = malloc(9000);
if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
goto out;
memset(buf, 0, 9000);
offset = (__u32 *)buf;
*offset = 5000;
buf[*offset] = 0xaa; /* marker at offset 5000 (frag0) */
buf[*offset + 15] = 0xaa; /* marker at offset 5015 (frag0) */
topts.data_in = buf;
topts.data_out = buf;
topts.data_size_in = 9000;
topts.data_size_out = 9000;
err = bpf_prog_test_run_opts(prog_fd, &topts);
/* test_xdp_update_frags: buf[5000,5015]: 0xaa -> 0xbb */
ASSERT_OK(err, "xdp_update_frag");
ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
ASSERT_EQ(buf[5000], 0xbb, "xdp_update_frag buf[5000]");
ASSERT_EQ(buf[5015], 0xbb, "xdp_update_frag buf[5015]");
memset(buf, 0, 9000);
offset = (__u32 *)buf;
*offset = 3510;
buf[*offset] = 0xaa; /* marker at offset 3510 (head) */
buf[*offset + 15] = 0xaa; /* marker at offset 3525 (frag0) */
err = bpf_prog_test_run_opts(prog_fd, &topts);
/* test_xdp_update_frags: buf[3510,3525]: 0xaa -> 0xbb */
ASSERT_OK(err, "xdp_update_frag");
ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
ASSERT_EQ(buf[3510], 0xbb, "xdp_update_frag buf[3510]");
ASSERT_EQ(buf[3525], 0xbb, "xdp_update_frag buf[3525]");
memset(buf, 0, 9000);
offset = (__u32 *)buf;
*offset = 7606;
Annotation
- Immediate include surface: `test_progs.h`, `network_helpers.h`.
- Detected declarations: `function test_xdp_update_frags`, `function test_xdp_adjust_frags`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.