| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #if ENV_X86_64 |
| #error COOP_MULTITASKING does not currently support x86_64 |
| #endif |
| |
| .code32 |
| .text |
| |
| /* |
| * stack layout after pushad: |
| * +------------+ |
| * | save stack | <-- esp + 0x28 |
| * +------------+ |
| * | new stack | <-- esp + 0x24 |
| * +------------+ |
| * | ret addr | <-- esp + 0x20 |
| * +------------+ |
| * | eax | <-- esp + 0x1c |
| * +------------+ |
| * | ecx | <-- esp + 0x18 |
| * +------------+ |
| * | edx | <-- esp + 0x14 |
| * +------------+ |
| * | ebx | <-- esp + 0x10 |
| * +------------+ |
| * | orig esp | <-- esp + 0x0c |
| * +------------+ |
| * | ebp | <-- esp + 0x08 |
| * +------------+ |
| * | esi | <-- esp + 0x04 |
| * +------------+ |
| * | edi | <-- esp + 0x00 |
| * +------------+ |
| */ |
| .globl switch_to_thread |
| switch_to_thread: |
| pusha |
| /* Save the current stack */ |
| movl 0x28(%esp), %ebx |
| movl %esp, (%ebx) |
| /* Switch to the new stack. */ |
| movl 0x24(%esp), %eax |
| movl %eax, %esp |
| popa |
| ret |