diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_core_read_macros.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_core_read_macros.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_core_read_macros.c b/tools/testing/selftests/bpf/progs/test_core_read_macros.c new file mode 100644 index 000000000000..fd54caa17319 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_read_macros.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2020 Facebook + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> + +char _license[] SEC("license") = "GPL"; + +/* shuffled layout for relocatable (CO-RE) reads */ +struct callback_head___shuffled { + void (*func)(struct callback_head___shuffled *head); + struct callback_head___shuffled *next; +}; + +struct callback_head k_probe_in = {}; +struct callback_head___shuffled k_core_in = {}; + +struct callback_head *u_probe_in = 0; +struct callback_head___shuffled *u_core_in = 0; + +long k_probe_out = 0; +long u_probe_out = 0; + +long k_core_out = 0; +long u_core_out = 0; + +int my_pid = 0; + +SEC("raw_tracepoint/sys_enter") +int handler(void *ctx) +{ + int pid = bpf_get_current_pid_tgid() >> 32; + + if (my_pid != pid) + return 0; + + /* next pointers for kernel address space have to be initialized from + * BPF side, user-space mmaped addresses are stil user-space addresses + */ + k_probe_in.next = &k_probe_in; + __builtin_preserve_access_index(({k_core_in.next = &k_core_in;})); + + k_probe_out = (long)BPF_PROBE_READ(&k_probe_in, next, next, func); + k_core_out = (long)BPF_CORE_READ(&k_core_in, next, next, func); + u_probe_out = (long)BPF_PROBE_READ_USER(u_probe_in, next, next, func); + u_core_out = (long)BPF_CORE_READ_USER(u_core_in, next, next, func); + + return 0; +} |