| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #include <linux/linkage.h> |
| #include <asm/export.h> |
| |
| .text |
| |
| /* |
| * Inputs: |
| * %esi : memory location to compare |
| * %eax : low 32 bits of old value |
| * %edx : high 32 bits of old value |
| * %ebx : low 32 bits of new value |
| * %ecx : high 32 bits of new value |
| */ |
| ENTRY(cmpxchg8b_emu) |
| |
| # |
| # Emulate 'cmpxchg8b (%esi)' on UP except we don't |
| # set the whole ZF thing (caller will just compare |
| # eax:edx with the expected value) |
| # |
| pushfl |
| cli |
| |
| cmpl (%esi), %eax |
| jne .Lnot_same |
| cmpl 4(%esi), %edx |
| jne .Lhalf_same |
| |
| movl %ebx, (%esi) |
| movl %ecx, 4(%esi) |
| |
| popfl |
| ret |
| |
| .Lnot_same: |
| movl (%esi), %eax |
| .Lhalf_same: |
| movl 4(%esi), %edx |
| |
| popfl |
| ret |
| |
| ENDPROC(cmpxchg8b_emu) |
| EXPORT_SYMBOL(cmpxchg8b_emu) |
