linux/arch/x86/um/shared/sysdep/stub_64.h
Benjamin Berg 7b84543cbd um: Always inline stub functions
The stub executable page is remapped to a different location in the
userland process. As these functions may be used by the stub, they
really need to be always inlined rather than permitting the compiler to
emit a function.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
2024-01-04 23:52:31 +01:00

126 lines
2.6 KiB
C

/*
* Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#ifndef __SYSDEP_STUB_H
#define __SYSDEP_STUB_H
#include <sysdep/ptrace_user.h>
#include <generated/asm-offsets.h>
#include <linux/stddef.h>
#define STUB_MMAP_NR __NR_mmap
#define MMAP_OFFSET(o) (o)
#define __syscall_clobber "r11","rcx","memory"
#define __syscall "syscall"
static __always_inline long stub_syscall0(long syscall)
{
long ret;
__asm__ volatile (__syscall
: "=a" (ret)
: "0" (syscall) : __syscall_clobber );
return ret;
}
static __always_inline long stub_syscall2(long syscall, long arg1, long arg2)
{
long ret;
__asm__ volatile (__syscall
: "=a" (ret)
: "0" (syscall), "D" (arg1), "S" (arg2) : __syscall_clobber );
return ret;
}
static __always_inline long stub_syscall3(long syscall, long arg1, long arg2,
long arg3)
{
long ret;
__asm__ volatile (__syscall
: "=a" (ret)
: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3)
: __syscall_clobber );
return ret;
}
static __always_inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
long arg4)
{
long ret;
__asm__ volatile ("movq %5,%%r10 ; " __syscall
: "=a" (ret)
: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
"g" (arg4)
: __syscall_clobber, "r10" );
return ret;
}
static __always_inline long stub_syscall5(long syscall, long arg1, long arg2,
long arg3, long arg4, long arg5)
{
long ret;
__asm__ volatile ("movq %5,%%r10 ; movq %6,%%r8 ; " __syscall
: "=a" (ret)
: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
"g" (arg4), "g" (arg5)
: __syscall_clobber, "r10", "r8" );
return ret;
}
static __always_inline void trap_myself(void)
{
__asm("int3");
}
static __always_inline void remap_stack_and_trap(void)
{
__asm__ volatile (
"movq %0,%%rax ;"
"movq %%rsp,%%rdi ;"
"andq %1,%%rdi ;"
"movq %2,%%r10 ;"
"movq %%rdi,%%r8 ; addq %3,%%r8 ; movq (%%r8),%%r8 ;"
"movq %%rdi,%%r9 ; addq %4,%%r9 ; movq (%%r9),%%r9 ;"
__syscall ";"
"movq %%rsp,%%rdi ; andq %1,%%rdi ;"
"addq %5,%%rdi ; movq %%rax, (%%rdi) ;"
"int3"
: :
"g" (STUB_MMAP_NR),
"g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
"g" (MAP_FIXED | MAP_SHARED),
"g" (UML_STUB_FIELD_FD),
"g" (UML_STUB_FIELD_OFFSET),
"g" (UML_STUB_FIELD_CHILD_ERR),
"S" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
"d" (PROT_READ | PROT_WRITE)
:
__syscall_clobber, "r10", "r8", "r9");
}
static __always_inline void *get_stub_data(void)
{
unsigned long ret;
asm volatile (
"movq %%rsp,%0 ;"
"andq %1,%0"
: "=a" (ret)
: "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
return (void *)ret;
}
#endif