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 <i386/linux/linux.h> 42 #include <i386/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 static int 55 write(int fd, const void *buf, size_t size) 56 { 57 int res; 58 59 __asm__ __volatile__ 60 ( 61 "int $0x80" 62 : "=a"(res) 63 : "a"(LINUX_SYS_linux_write), "b"(fd), "c"(buf), "d"(size) 64 : "cc", "memory" 65 ); 66 return (res); 67 } 68 69 static int 70 __vdso_clock_gettime_fallback(clockid_t clock_id, struct l_timespec *ts) 71 { 72 int res; 73 74 __asm__ __volatile__ 75 ( 76 "int $0x80" 77 : "=a"(res) 78 : "a"(LINUX_SYS_linux_clock_gettime), "b"(clock_id), "c"(ts) 79 : "cc", "memory" 80 ); 81 return (res); 82 } 83 84 static int 85 __vdso_clock_gettime64_fallback(clockid_t clock_id, struct l_timespec64 *ts) 86 { 87 int res; 88 89 __asm__ __volatile__ 90 ( 91 "int $0x80" 92 : "=a"(res) 93 : "a"(LINUX_SYS_linux_clock_gettime64), "b"(clock_id), "c"(ts) 94 : "cc", "memory" 95 ); 96 return (res); 97 } 98 99 static int 100 __vdso_gettimeofday_fallback(l_timeval *tv, struct timezone *tz) 101 { 102 int res; 103 104 __asm__ __volatile__ 105 ( 106 "int $0x80" 107 : "=a"(res) 108 : "a"(LINUX_SYS_gettimeofday), "b"(tv), "c"(tz) 109 : "cc", "memory" 110 ); 111 return (res); 112 } 113 114 static int 115 __vdso_clock_getres_fallback(clockid_t clock_id, struct l_timespec *ts) 116 { 117 int res; 118 119 __asm__ __volatile__ 120 ( 121 "int $0x80" 122 : "=a"(res) 123 : "a"(LINUX_SYS_linux_clock_getres), "b"(clock_id), "c"(ts) 124 : "cc", "memory" 125 ); 126 return (res); 127 } 128 129 static int 130 __vdso_getcpu_fallback(uint32_t *cpu, uint32_t *node, void *cache) 131 { 132 int res; 133 134 __asm__ __volatile__ 135 ( 136 "int $0x80" 137 : "=a"(res) 138 : "a"(LINUX_SYS_linux_getcpu), "D"(cpu), "S"(node), "d"(cache) 139 : "cc", "memory" 140 ); 141 return (res); 142 } 143 144 static int 145 __vdso_time_fallback(long *tm) 146 { 147 int res; 148 149 __asm__ __volatile__ 150 ( 151 "int $0x80" 152 : "=a"(res) 153 : "a"(LINUX_SYS_linux_time), "b"(tm) 154 : "cc", "memory" 155 ); 156 return (res); 157 } 158 159 #include <compat/linux/linux_vdso_gtod.inc> 160