/arch/um/sys-x86_64/shared/sysdep/stub.h

  1/*
  2 * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
  3 * Licensed under the GPL
  4 */
  5
  6#ifndef __SYSDEP_STUB_H
  7#define __SYSDEP_STUB_H
  8
  9#include <sys/mman.h>
 10#include <asm/unistd.h>
 11#include <sysdep/ptrace_user.h>
 12#include "as-layout.h"
 13#include "stub-data.h"
 14#include "kern_constants.h"
 15
 16extern void stub_segv_handler(int sig);
 17extern void stub_clone_handler(void);
 18
 19#define STUB_SYSCALL_RET PT_INDEX(RAX)
 20#define STUB_MMAP_NR __NR_mmap
 21#define MMAP_OFFSET(o) (o)
 22
 23#define __syscall_clobber "r11","rcx","memory"
 24#define __syscall "syscall"
 25
 26static inline long stub_syscall0(long syscall)
 27{
 28	long ret;
 29
 30	__asm__ volatile (__syscall
 31		: "=a" (ret)
 32		: "0" (syscall) : __syscall_clobber );
 33
 34	return ret;
 35}
 36
 37static inline long stub_syscall2(long syscall, long arg1, long arg2)
 38{
 39	long ret;
 40
 41	__asm__ volatile (__syscall
 42		: "=a" (ret)
 43		: "0" (syscall), "D" (arg1), "S" (arg2) : __syscall_clobber );
 44
 45	return ret;
 46}
 47
 48static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
 49{
 50	long ret;
 51
 52	__asm__ volatile (__syscall
 53		: "=a" (ret)
 54		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3)
 55		: __syscall_clobber );
 56
 57	return ret;
 58}
 59
 60static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
 61				 long arg4)
 62{
 63	long ret;
 64
 65	__asm__ volatile ("movq %5,%%r10 ; " __syscall
 66		: "=a" (ret)
 67		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
 68		  "g" (arg4)
 69		: __syscall_clobber, "r10" );
 70
 71	return ret;
 72}
 73
 74static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
 75				 long arg4, long arg5)
 76{
 77	long ret;
 78
 79	__asm__ volatile ("movq %5,%%r10 ; movq %6,%%r8 ; " __syscall
 80		: "=a" (ret)
 81		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
 82		  "g" (arg4), "g" (arg5)
 83		: __syscall_clobber, "r10", "r8" );
 84
 85	return ret;
 86}
 87
 88static inline void trap_myself(void)
 89{
 90	__asm("int3");
 91}
 92
 93static inline void remap_stack(long fd, unsigned long offset)
 94{
 95	__asm__ volatile ("movq %4,%%r10 ; movq %5,%%r8 ; "
 96			  "movq %6, %%r9; " __syscall "; movq %7, %%rbx ; "
 97			  "movq %%rax, (%%rbx)":
 98			  : "a" (STUB_MMAP_NR), "D" (STUB_DATA),
 99			    "S" (UM_KERN_PAGE_SIZE),
100			    "d" (PROT_READ | PROT_WRITE),
101                            "g" (MAP_FIXED | MAP_SHARED), "g" (fd),
102			    "g" (offset),
103			    "i" (&((struct stub_data *) STUB_DATA)->err)
104			  : __syscall_clobber, "r10", "r8", "r9" );
105}
106
107#endif