1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 Dmitry Chagin <dchagin@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/elf.h> 29 #include <sys/errno.h> 30 #include <sys/proc.h> 31 #include <sys/stddef.h> 32 #define _KERNEL 33 #include <sys/vdso.h> 34 #undef _KERNEL 35 #include <stdbool.h> 36 37 #include <machine/atomic.h> 38 #include <machine/cpufunc.h> 39 #include <machine/stdarg.h> 40 41 #include <amd64/linux/linux.h> 42 #include <amd64/linux/linux_syscall.h> 43 #include <compat/linux/linux_errno.h> 44 #include <compat/linux/linux_time.h> 45 46 /* The kernel fixup this at vDSO install */ 47 uintptr_t *kern_timekeep_base = NULL; 48 uint32_t kern_tsc_selector = 0; 49 uint32_t kern_cpu_selector = 0; 50 51 #include <x86/linux/linux_vdso_gettc_x86.inc> 52 #include <x86/linux/linux_vdso_getcpu_x86.inc> 53 54 /* for debug purpose */ 55 static int 56 write(int fd, const void *buf, size_t size) 57 { 58 int res; 59 60 __asm__ __volatile__ 61 ( 62 "syscall" 63 : "=a"(res) 64 : "a"(LINUX_SYS_linux_write), "D"(fd), "S"(buf), "d"(size) 65 : "cc", "rcx", "r11", "memory" 66 ); 67 return (res); 68 } 69 70 static int 71 __vdso_clock_gettime_fallback(clockid_t clock_id, struct l_timespec *ts) 72 { 73 int res; 74 75 __asm__ __volatile__ 76 ( 77 "syscall" 78 : "=a"(res) 79 : "a"(LINUX_SYS_linux_clock_gettime), "D"(clock_id), "S"(ts) 80 : "cc", "rcx", "r11", "memory" 81 ); 82 return (res); 83 } 84 85 static int 86 __vdso_gettimeofday_fallback(l_timeval *tv, struct timezone *tz) 87 { 88 int res; 89 90 __asm__ __volatile__ 91 ( 92 "syscall" 93 : "=a"(res) 94 : "a"(LINUX_SYS_gettimeofday), "D"(tv), "S"(tz) 95 : "cc", "rcx", "r11", "memory" 96 ); 97 return (res); 98 } 99 100 static int 101 __vdso_clock_getres_fallback(clockid_t clock_id, struct l_timespec *ts) 102 { 103 int res; 104 105 __asm__ __volatile__ 106 ( 107 "syscall" 108 : "=a"(res) 109 : "a"(LINUX_SYS_linux_clock_getres), "D"(clock_id), "S"(ts) 110 : "cc", "rcx", "r11", "memory" 111 ); 112 return (res); 113 } 114 115 static int 116 __vdso_getcpu_fallback(uint32_t *cpu, uint32_t *node, void *cache) 117 { 118 int res; 119 120 __asm__ __volatile__ 121 ( 122 "syscall" 123 : "=a"(res) 124 : "a"(LINUX_SYS_linux_getcpu), "D"(cpu), "S"(node), "d"(cache) 125 : "cc", "rcx", "r11", "memory" 126 ); 127 return (res); 128 } 129 130 static int 131 __vdso_time_fallback(long *tm) 132 { 133 int res; 134 135 __asm__ __volatile__ 136 ( 137 "syscall" 138 : "=a"(res) 139 : "a"(LINUX_SYS_linux_time), "D"(tm) 140 : "cc", "rcx", "r11", "memory" 141 ); 142 return (res); 143 } 144 145 #include <compat/linux/linux_vdso_gtod.inc> 146