| Thomas Gleixner | b886d83c | 2019-06-01 10:08:55 +0200 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 2 | |
| 3 | #include <linux/linkage.h> | ||||
| Al Viro | 784d569 | 2016-01-11 11:04:34 -0500 | [diff] [blame] | 4 | #include <asm/export.h> |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 5 | |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 6 | .text |
| 7 | |||||
| 8 | /* | ||||
| 9 | * Inputs: | ||||
| 10 | * %esi : memory location to compare | ||||
| 11 | * %eax : low 32 bits of old value | ||||
| 12 | * %edx : high 32 bits of old value | ||||
| 13 | * %ebx : low 32 bits of new value | ||||
| 14 | * %ecx : high 32 bits of new value | ||||
| 15 | */ | ||||
| Jiri Slaby | 6dcc562 | 2019-10-11 13:51:04 +0200 | [diff] [blame] | 16 | SYM_FUNC_START(cmpxchg8b_emu) |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 17 | |
| 18 | # | ||||
| 19 | # Emulate 'cmpxchg8b (%esi)' on UP except we don't | ||||
| 20 | # set the whole ZF thing (caller will just compare | ||||
| 21 | # eax:edx with the expected value) | ||||
| 22 | # | ||||
| Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 23 | pushfl |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 24 | cli |
| 25 | |||||
| 26 | cmpl (%esi), %eax | ||||
| Jan Beulich | 5f1d919 | 2014-09-24 08:40:14 +0100 | [diff] [blame] | 27 | jne .Lnot_same |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 28 | cmpl 4(%esi), %edx |
| Jan Beulich | 5f1d919 | 2014-09-24 08:40:14 +0100 | [diff] [blame] | 29 | jne .Lhalf_same |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 30 | |
| 31 | movl %ebx, (%esi) | ||||
| 32 | movl %ecx, 4(%esi) | ||||
| 33 | |||||
| Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 34 | popfl |
| Peter Zijlstra | f94909c | 2021-12-04 14:43:40 +0100 | [diff] [blame] | 35 | RET |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 36 | |
| Jan Beulich | 5f1d919 | 2014-09-24 08:40:14 +0100 | [diff] [blame] | 37 | .Lnot_same: |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 38 | movl (%esi), %eax |
| Jan Beulich | 5f1d919 | 2014-09-24 08:40:14 +0100 | [diff] [blame] | 39 | .Lhalf_same: |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 40 | movl 4(%esi), %edx |
| 41 | |||||
| Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 42 | popfl |
| Peter Zijlstra | f94909c | 2021-12-04 14:43:40 +0100 | [diff] [blame] | 43 | RET |
| Arjan van de Ven | 79e1dd0 | 2009-09-30 17:07:54 +0200 | [diff] [blame] | 44 | |
| Jiri Slaby | 6dcc562 | 2019-10-11 13:51:04 +0200 | [diff] [blame] | 45 | SYM_FUNC_END(cmpxchg8b_emu) |
| Al Viro | 784d569 | 2016-01-11 11:04:34 -0500 | [diff] [blame] | 46 | EXPORT_SYMBOL(cmpxchg8b_emu) |