cloud-email/mitmproxy - clone of mitm proxy

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/* -*- Mode:C; c-basic-offset:4; tab-width:4 -*- **************************************************************************** * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge * (C) 2002-2003 - Keir Fraser - University of Cambridge * (C) 2005 - Grzegorz Milos - Intel Research Cambridge **************************************************************************** * * File: time.c * Author: Rolf Neugebauer and Keir Fraser * Changes: Grzegorz Milos * * Description: Simple time and timer functions * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to * deal in the Software without restriction, including without limitation the * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or * sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ #include <os.h> #include <traps.h> #include <types.h> #include <hypervisor.h> #include <events.h> #include <time.h> #include <lib.h> /************************************************************************ * Time functions *************************************************************************/ /* These are peridically updated in shared_info, and then copied here. */ struct shadow_time_info { u64 tsc_timestamp; /* TSC at last update of time vals. */ u64 system_timestamp; /* Time, in nanosecs, since boot. */ u32 tsc_to_nsec_mul; u32 tsc_to_usec_mul; int tsc_shift; u32 version; }; static struct timespec shadow_ts; static u32 shadow_ts_version; static struct shadow_time_info shadow; #ifndef rmb #define rmb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory") #endif #define HANDLE_USEC_OVERFLOW(_tv) \ do { \ while ( (_tv)->tv_usec >= 1000000 ) \ { \ (_tv)->tv_usec -= 1000000; \ (_tv)->tv_sec++; \ } \ } while ( 0 ) static inline int time_values_up_to_date(void) { struct vcpu_time_info *src = &HYPERVISOR_shared_info->vcpu_info[0].time; return (shadow.version == src->version); } /* * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction, * yielding a 64-bit result. */ static inline u64 scale_delta(u64 delta, u32 mul_frac, int shift) { u64 product; #ifdef __i386__ u32 tmp1, tmp2; #endif if ( shift < 0 ) delta >>= -shift; else delta <<= shift; #ifdef __i386__ __asm__ ( "mul %5 ; " "mov %4,%%eax ; " "mov %%edx,%4 ; " "mul %5 ; " "add %4,%%eax ; " "xor %5,%5 ; " "adc %5,%%edx ; " : "=A" (product), "=r" (tmp1), "=r" (tmp2) : "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) ); #else __asm__ ( "mul %%rdx ; shrd $32,%%rdx,%%rax" : "=a" (product) : "0" (delta), "d" ((u64)mul_frac) ); #endif return product; } static unsigned long get_nsec_offset(void) { u64 now, delta; rdtscll(now); delta = now - shadow.tsc_timestamp; return scale_delta(delta, shadow.tsc_to_nsec_mul, shadow.tsc_shift); } static void get_time_values_from_xen(void) { struct vcpu_time_info *src = &HYPERVISOR_shared_info->vcpu_info[0].time; do { shadow.version = src->version; rmb(); shadow.tsc_timestamp = src->tsc_timestamp; shadow.system_timestamp = src->system_time; shadow.tsc_to_nsec_mul = src->tsc_to_system_mul; shadow.tsc_shift = src->tsc_shift; rmb(); } while ((src->version & 1) | (shadow.version ^ src->version)); shadow.tsc_to_usec_mul = shadow.tsc_to_nsec_mul / 1000; } /* monotonic_clock(): returns # of nanoseconds passed since time_init() * Note: This function is required to return accurate * time even in the absence of multiple timer ticks. */ u64 monotonic_clock(void) { u64 time; u32 local_time_version; do { local_time_version = shadow.version; rmb(); time = shadow.system_timestamp + get_nsec_offset(); if (!time_values_up_to_date()) get_time_values_from_xen(); rmb(); } while (local_time_version != shadow.version); return time; } static void update_wallclock(void) { shared_info_t *s = HYPERVISOR_shared_info; do { shadow_ts_version = s->wc_version; rmb(); shadow_ts.ts_sec = s->wc_sec; shadow_ts.ts_nsec = s->wc_nsec; rmb(); } while ((s->wc_version & 1) | (shadow_ts_version ^ s->wc_version)); } void gettimeofday(struct timeval *tv) { u64 nsec = monotonic_clock(); nsec += shadow_ts.ts_nsec; tv->tv_sec = shadow_ts.ts_sec; tv->tv_sec += NSEC_TO_SEC(nsec); tv->tv_usec = NSEC_TO_USEC(nsec % 1000000000UL); } static void print_current_time(void) { struct timeval tv; gettimeofday(&tv); printk("T(s=%ld us=%ld)\n", tv.tv_sec, tv.tv_usec); } void block_domain(u32 millisecs) { struct timeval tv; gettimeofday(&tv); HYPERVISOR_set_timer_op(monotonic_clock() + 1000000LL * (s64) millisecs); HYPERVISOR_sched_op(SCHEDOP_block, 0); } /* * Just a dummy */ static void timer_handler(int ev, struct pt_regs *regs) { static int i; get_time_values_from_xen(); update_wallclock(); i++; if (i >= 1000) { print_current_time(); i = 0; } } void init_time(void) { printk("Initialising timer interface\n"); bind_virq(VIRQ_TIMER, &timer_handler); }


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