tools/testing/selftests/bpf/prog_tests/map_excl.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/prog_tests/map_excl.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/prog_tests/map_excl.c- Extension
.c- Size
- 5128 bytes
- Lines
- 177
- 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
unistd.hsys/syscall.htest_progs.hbpf/btf.hmap_excl.skel.hbpf_iter_bpf_array_map.skel.h
Detected Declarations
function test_map_excl_allowedfunction test_map_excl_deniedfunction test_map_excl_no_map_in_mapfunction test_map_excl_no_map_iterfunction test_map_excl_create_validationfunction test_map_excl
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2025 Google LLC. */
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <test_progs.h>
#include <bpf/btf.h>
#include "map_excl.skel.h"
#include "bpf_iter_bpf_array_map.skel.h"
#ifndef SHA256_DIGEST_SIZE
#define SHA256_DIGEST_SIZE 32
#endif
static void test_map_excl_allowed(void)
{
struct map_excl *skel = map_excl__open();
int err;
err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
if (!ASSERT_OK(err, "bpf_map__set_exclusive_program"))
goto out;
bpf_program__set_autoload(skel->progs.should_have_access, true);
bpf_program__set_autoload(skel->progs.should_not_have_access, false);
err = map_excl__load(skel);
ASSERT_OK(err, "map_excl__load");
out:
map_excl__destroy(skel);
}
static void test_map_excl_denied(void)
{
struct map_excl *skel = map_excl__open();
int err;
err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
if (!ASSERT_OK(err, "bpf_map__make_exclusive"))
goto out;
bpf_program__set_autoload(skel->progs.should_have_access, false);
bpf_program__set_autoload(skel->progs.should_not_have_access, true);
err = map_excl__load(skel);
ASSERT_EQ(err, -EACCES, "exclusive map access not denied\n");
out:
map_excl__destroy(skel);
}
static void test_map_excl_no_map_in_map(void)
{
__u8 hash[SHA256_DIGEST_SIZE] = {};
LIBBPF_OPTS(bpf_map_create_opts, excl_opts,
.excl_prog_hash = hash,
.excl_prog_hash_size = sizeof(hash));
LIBBPF_OPTS(bpf_map_create_opts, outer_opts);
int excl_fd, tmpl_fd = -1, outer_fd = -1, err;
__u32 key = 0;
excl_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "excl_inner", 4, 4, 1, &excl_opts);
if (!ASSERT_OK_FD(excl_fd, "create exclusive map"))
return;
outer_opts.inner_map_fd = excl_fd;
err = bpf_map_create(BPF_MAP_TYPE_ARRAY_OF_MAPS, "outer_from_excl",
4, 4, 1, &outer_opts);
if (err >= 0)
close(err);
ASSERT_EQ(err, -ENOTSUPP, "reject exclusive map as map-in-map template");
tmpl_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "tmpl", 4, 4, 1, NULL);
if (!ASSERT_OK_FD(tmpl_fd, "create inner template"))
goto out;
outer_opts.inner_map_fd = tmpl_fd;
outer_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY_OF_MAPS, "outer", 4, 4, 1, &outer_opts);
if (!ASSERT_OK_FD(outer_fd, "create map-of-maps"))
goto out;
err = bpf_map_update_elem(outer_fd, &key, &excl_fd, 0);
ASSERT_EQ(err, -ENOTSUPP, "reject exclusive map as map-in-map element");
out:
if (outer_fd >= 0)
close(outer_fd);
if (tmpl_fd >= 0)
close(tmpl_fd);
close(excl_fd);
Annotation
- Immediate include surface: `unistd.h`, `sys/syscall.h`, `test_progs.h`, `bpf/btf.h`, `map_excl.skel.h`, `bpf_iter_bpf_array_map.skel.h`.
- Detected declarations: `function test_map_excl_allowed`, `function test_map_excl_denied`, `function test_map_excl_no_map_in_map`, `function test_map_excl_no_map_iter`, `function test_map_excl_create_validation`, `function test_map_excl`.
- 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.