name : compat_gettimeofday.h /* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright (C) 2018 ARM Limited */ #ifndef __ASM_VDSO_GETTIMEOFDAY_H #define __ASM_VDSO_GETTIMEOFDAY_H #ifndef __ASSEMBLY__ #include <asm/barrier.h> #include <asm/unistd.h> #include <asm/errno.h> #include <asm/vdso/compat_barrier.h> #define VDSO_HAS_CLOCK_GETRES 1 #define BUILD_VDSO32 1 static __always_inline int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz) { register struct timezone *tz asm("r1") = _tz; register struct __kernel_old_timeval *tv asm("r0") = _tv; register long ret asm ("r0"); register long nr asm("r7") = __NR_compat_gettimeofday; asm volatile( " swi #0\n" : "=r" (ret) : "r" (tv), "r" (tz), "r" (nr) : "memory"); return ret; } static __always_inline long clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts) { register struct __kernel_timespec *ts asm("r1") = _ts; register clockid_t clkid asm("r0") = _clkid; register long ret asm ("r0"); register long nr asm("r7") = __NR_compat_clock_gettime64; asm volatile( " swi #0\n" : "=r" (ret) : "r" (clkid), "r" (ts), "r" (nr) : "memory"); return ret; } static __always_inline long clock_gettime32_fallback(clockid_t _clkid, struct old_timespec32 *_ts) { register struct old_timespec32 *ts asm("r1") = _ts; register clockid_t clkid asm("r0") = _clkid; register long ret asm ("r0"); register long nr asm("r7") = __NR_compat_clock_gettime; asm volatile( " swi #0\n" : "=r" (ret) : "r" (clkid), "r" (ts), "r" (nr) : "memory"); return ret; } static __always_inline int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts) { register struct __kernel_timespec *ts asm("r1") = _ts; register clockid_t clkid asm("r0") = _clkid; register long ret asm ("r0"); register long nr asm("r7") = __NR_compat_clock_getres_time64; asm volatile( " swi #0\n" : "=r" (ret) : "r" (clkid), "r" (ts), "r" (nr) : "memory"); return ret; } static __always_inline int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts) { register struct old_timespec32 *ts asm("r1") = _ts; register clockid_t clkid asm("r0") = _clkid; register long ret asm ("r0"); register long nr asm("r7") = __NR_compat_clock_getres; asm volatile( " swi #0\n" : "=r" (ret) : "r" (clkid), "r" (ts), "r" (nr) : "memory"); return ret; } static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, const struct vdso_data *vd) { u64 res; /* * Core checks for mode already, so this raced against a concurrent * update. Return something. Core will do another round and then * see the mode change and fallback to the syscall. */ if (clock_mode != VDSO_CLOCKMODE_ARCHTIMER) return 0; /* * This isb() is required to prevent that the counter value * is speculated. */ isb(); asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (res)); /* * This isb() is required to prevent that the seq lock is * speculated. */ isb(); return res; } static __always_inline const struct vdso_data *__arch_get_vdso_data(void) { const struct vdso_data *ret; /* * This simply puts &_vdso_data into ret. The reason why we don't use * `ret = _vdso_data` is that the compiler tends to optimise this in a * very suboptimal way: instead of keeping &_vdso_data in a register, * it goes through a relocation almost every time _vdso_data must be * accessed (even in subfunctions). This is both time and space * consuming: each relocation uses a word in the code section, and it * has to be loaded at runtime. * * This trick hides the assignment from the compiler. Since it cannot * track where the pointer comes from, it will only use one relocation * where __arch_get_vdso_data() is called, and then keep the result in * a register. */ asm volatile("mov %0, %1" : "=r"(ret) : "r"(_vdso_data)); return ret; } #ifdef CONFIG_TIME_NS static __always_inline const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd) { const struct vdso_data *ret; /* See __arch_get_vdso_data(). */ asm volatile("mov %0, %1" : "=r"(ret) : "r"(_timens_data)); return ret; } #endif static inline bool vdso_clocksource_ok(const struct vdso_data *vd) { return vd->clock_mode == VDSO_CLOCKMODE_ARCHTIMER; } #define vdso_clocksource_ok vdso_clocksource_ok #endif /* !__ASSEMBLY__ */ #endif /* __ASM_VDSO_GETTIMEOFDAY_H */