mirror of
https://github.com/torvalds/linux.git
synced 2024-12-12 14:12:51 +00:00
2025cf9e19
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 263 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
48 lines
843 B
ArmAsm
48 lines
843 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* thunks_32.S - assembly helpers for mixed-bitness code
|
|
* Copyright (c) 2015 Denys Vlasenko
|
|
*
|
|
* These are little helpers that make it easier to switch bitness on
|
|
* the fly.
|
|
*/
|
|
|
|
.text
|
|
.code32
|
|
|
|
.global call64_from_32
|
|
.type call32_from_64, @function
|
|
|
|
// 4(%esp): function to call
|
|
call64_from_32:
|
|
// Fetch function address
|
|
mov 4(%esp), %eax
|
|
|
|
// Save registers which are callee-clobbered by 64-bit ABI
|
|
push %ecx
|
|
push %edx
|
|
push %esi
|
|
push %edi
|
|
|
|
// Switch to long mode
|
|
jmp $0x33,$1f
|
|
1: .code64
|
|
|
|
// Call the function
|
|
call *%rax
|
|
|
|
// Switch to compatibility mode
|
|
push $0x23 /* USER32_CS */
|
|
.code32; push $1f; .code64 /* hack: can't have X86_64_32S relocation in 32-bit ELF */
|
|
lretq
|
|
1: .code32
|
|
|
|
pop %edi
|
|
pop %esi
|
|
pop %edx
|
|
pop %ecx
|
|
|
|
ret
|
|
|
|
.size call64_from_32, .-call64_from_32
|