1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* 3 * atomic64_t for 386/486 4 * 5 * Copyright © 2010 Luca Barbieri 6 */ 7 8#include <linux/linkage.h> 9#include <asm/alternative-asm.h> 10 11/* if you want SMP support, implement these with real spinlocks */ 12.macro LOCK reg 13 pushfl 14 cli 15.endm 16 17.macro UNLOCK reg 18 popfl 19.endm 20 21#define BEGIN(op) \ 22.macro endp; \ 23SYM_FUNC_END(atomic64_##op##_386); \ 24.purgem endp; \ 25.endm; \ 26SYM_FUNC_START(atomic64_##op##_386); \ 27 LOCK v; 28 29#define ENDP endp 30 31#define RET \ 32 UNLOCK v; \ 33 ret 34 35#define RET_ENDP \ 36 RET; \ 37 ENDP 38 39#define v %ecx 40BEGIN(read) 41 movl (v), %eax 42 movl 4(v), %edx 43RET_ENDP 44#undef v 45 46#define v %esi 47BEGIN(set) 48 movl %ebx, (v) 49 movl %ecx, 4(v) 50RET_ENDP 51#undef v 52 53#define v %esi 54BEGIN(xchg) 55 movl (v), %eax 56 movl 4(v), %edx 57 movl %ebx, (v) 58 movl %ecx, 4(v) 59RET_ENDP 60#undef v 61 62#define v %ecx 63BEGIN(add) 64 addl %eax, (v) 65 adcl %edx, 4(v) 66RET_ENDP 67#undef v 68 69#define v %ecx 70BEGIN(add_return) 71 addl (v), %eax 72 adcl 4(v), %edx 73 movl %eax, (v) 74 movl %edx, 4(v) 75RET_ENDP 76#undef v 77 78#define v %ecx 79BEGIN(sub) 80 subl %eax, (v) 81 sbbl %edx, 4(v) 82RET_ENDP 83#undef v 84 85#define v %ecx 86BEGIN(sub_return) 87 negl %edx 88 negl %eax 89 sbbl $0, %edx 90 addl (v), %eax 91 adcl 4(v), %edx 92 movl %eax, (v) 93 movl %edx, 4(v) 94RET_ENDP 95#undef v 96 97#define v %esi 98BEGIN(inc) 99 addl $1, (v) 100 adcl $0, 4(v) 101RET_ENDP 102#undef v 103 104#define v %esi 105BEGIN(inc_return) 106 movl (v), %eax 107 movl 4(v), %edx 108 addl $1, %eax 109 adcl $0, %edx 110 movl %eax, (v) 111 movl %edx, 4(v) 112RET_ENDP 113#undef v 114 115#define v %esi 116BEGIN(dec) 117 subl $1, (v) 118 sbbl $0, 4(v) 119RET_ENDP 120#undef v 121 122#define v %esi 123BEGIN(dec_return) 124 movl (v), %eax 125 movl 4(v), %edx 126 subl $1, %eax 127 sbbl $0, %edx 128 movl %eax, (v) 129 movl %edx, 4(v) 130RET_ENDP 131#undef v 132 133#define v %esi 134BEGIN(add_unless) 135 addl %eax, %ecx 136 adcl %edx, %edi 137 addl (v), %eax 138 adcl 4(v), %edx 139 cmpl %eax, %ecx 140 je 3f 1411: 142 movl %eax, (v) 143 movl %edx, 4(v) 144 movl $1, %eax 1452: 146 RET 1473: 148 cmpl %edx, %edi 149 jne 1b 150 xorl %eax, %eax 151 jmp 2b 152ENDP 153#undef v 154 155#define v %esi 156BEGIN(inc_not_zero) 157 movl (v), %eax 158 movl 4(v), %edx 159 testl %eax, %eax 160 je 3f 1611: 162 addl $1, %eax 163 adcl $0, %edx 164 movl %eax, (v) 165 movl %edx, 4(v) 166 movl $1, %eax 1672: 168 RET 1693: 170 testl %edx, %edx 171 jne 1b 172 jmp 2b 173ENDP 174#undef v 175 176#define v %esi 177BEGIN(dec_if_positive) 178 movl (v), %eax 179 movl 4(v), %edx 180 subl $1, %eax 181 sbbl $0, %edx 182 js 1f 183 movl %eax, (v) 184 movl %edx, 4(v) 1851: 186RET_ENDP 187#undef v 188