1 /* 2 * Copyright (C) 2011 Richard Weinberger <richrd@nod.at> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This vDSO turns all calls into a syscall so that UML can trap them. 9 */ 10 11 12 /* Disable profiling for userspace code */ 13 #define DISABLE_BRANCH_PROFILING 14 15 #include <linux/time.h> 16 #include <linux/getcpu.h> 17 #include <asm/unistd.h> 18 19 int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) 20 { 21 long ret; 22 23 asm("syscall" : "=a" (ret) : 24 "0" (__NR_clock_gettime), "D" (clock), "S" (ts) : "memory"); 25 26 return ret; 27 } 28 int clock_gettime(clockid_t, struct timespec *) 29 __attribute__((weak, alias("__vdso_clock_gettime"))); 30 31 int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) 32 { 33 long ret; 34 35 asm("syscall" : "=a" (ret) : 36 "0" (__NR_gettimeofday), "D" (tv), "S" (tz) : "memory"); 37 38 return ret; 39 } 40 int gettimeofday(struct timeval *, struct timezone *) 41 __attribute__((weak, alias("__vdso_gettimeofday"))); 42 43 time_t __vdso_time(time_t *t) 44 { 45 long secs; 46 47 asm volatile("syscall" 48 : "=a" (secs) 49 : "0" (__NR_time), "D" (t) : "cc", "r11", "cx", "memory"); 50 51 return secs; 52 } 53 int time(time_t *t) __attribute__((weak, alias("__vdso_time"))); 54 55 long 56 __vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused) 57 { 58 /* 59 * UML does not support SMP, we can cheat here. :) 60 */ 61 62 if (cpu) 63 *cpu = 0; 64 if (node) 65 *node = 0; 66 67 return 0; 68 } 69 70 long getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache) 71 __attribute__((weak, alias("__vdso_getcpu"))); 72