1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 3 #ifndef PARSE_VDSO_H 4 #define PARSE_VDSO_H 5 6 #include <stdint.h> 7 8 /* 9 * To use this vDSO parser, first call one of the vdso_init_* functions. 10 * If you've already parsed auxv, then pass the value of AT_SYSINFO_EHDR 11 * to vdso_init_from_sysinfo_ehdr. Otherwise pass auxv to vdso_init_from_auxv. 12 * Then call vdso_sym for each symbol you want. For example, to look up 13 * gettimeofday on x86_64, use: 14 * 15 * <some pointer> = vdso_sym("LINUX_2.6", "gettimeofday"); 16 * or 17 * <some pointer> = vdso_sym("LINUX_2.6", "__vdso_gettimeofday"); 18 * 19 * vdso_sym will return 0 if the symbol doesn't exist or if the init function 20 * failed or was not called. vdso_sym is a little slow, so its return value 21 * should be cached. 22 * 23 * vdso_sym is threadsafe; the init functions are not. 24 * 25 * These are the prototypes: 26 */ 27 void *vdso_sym(const char *version, const char *name); 28 void vdso_init_from_sysinfo_ehdr(uintptr_t base); 29 void vdso_init_from_auxv(void *auxv); 30 31 #endif 32