linux/tools/testing/selftests/vDSO/parse_vdso.h
Mark Brown cd76ca4dd6 selftests: vdso: Use a header file to prototype parse_vdso API
Both vdso_test_gettimeofday and vdso_standalone_test_x86 use the library in
parse_vdso.c but each separately declares the API it offers which is not
ideal. Create a header file with prototypes of the functions and use it in
both the library and the tests to ensure that the same prototypes are used
throughout.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-05-22 11:04:10 -06:00

32 lines
1009 B
C

/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef PARSE_VDSO_H
#define PARSE_VDSO_H
#include <stdint.h>
/*
* To use this vDSO parser, first call one of the vdso_init_* functions.
* If you've already parsed auxv, then pass the value of AT_SYSINFO_EHDR
* to vdso_init_from_sysinfo_ehdr. Otherwise pass auxv to vdso_init_from_auxv.
* Then call vdso_sym for each symbol you want. For example, to look up
* gettimeofday on x86_64, use:
*
* <some pointer> = vdso_sym("LINUX_2.6", "gettimeofday");
* or
* <some pointer> = vdso_sym("LINUX_2.6", "__vdso_gettimeofday");
*
* vdso_sym will return 0 if the symbol doesn't exist or if the init function
* failed or was not called. vdso_sym is a little slow, so its return value
* should be cached.
*
* vdso_sym is threadsafe; the init functions are not.
*
* These are the prototypes:
*/
void *vdso_sym(const char *version, const char *name);
void vdso_init_from_sysinfo_ehdr(uintptr_t base);
void vdso_init_from_auxv(void *auxv);
#endif