arch/um/include/sysdep-x86_64/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 #include "uml-config.h"
  16
  17 extern void stub_segv_handler(int sig);
  18 extern void stub_clone_handler(void);
  19
  20 #define STUB_SYSCALL_RET PT_INDEX(RAX)
  21 #define STUB_MMAP_NR __NR_mmap
  22 #define MMAP_OFFSET(o) (o)
  23
  24 #define __syscall_clobber "r11","rcx","memory"
  25 #define __syscall "syscall"
  26
  27 static inline long stub_syscall0(long syscall)
  28 {
  29         long ret;
  30
  31         __asm__ volatile (__syscall
  32                 : "=a" (ret)
  33                 : "0" (syscall) : __syscall_clobber );
  34
  35         return ret;
  36 }
  37
  38 static inline long stub_syscall2(long syscall, long arg1, long arg2)
  39 {
  40         long ret;
  41
  42         __asm__ volatile (__syscall
  43                 : "=a" (ret)
  44                 : "0" (syscall), "D" (arg1), "S" (arg2) : __syscall_clobber );
  45
  46         return ret;
  47 }
  48
  49 static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
  50 {
  51         long ret;
  52
  53         __asm__ volatile (__syscall
  54                 : "=a" (ret)
  55                 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3)
  56                 : __syscall_clobber );
  57
  58         return ret;
  59 }
  60
  61 static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
  62                                  long arg4)
  63 {
  64         long ret;
  65
  66         __asm__ volatile ("movq %5,%%r10 ; " __syscall
  67                 : "=a" (ret)
  68                 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
  69                   "g" (arg4)
  70                 : __syscall_clobber, "r10" );
  71
  72         return ret;
  73 }
  74
  75 static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
  76                                  long arg4, long arg5)
  77 {
  78         long ret;
  79
  80         __asm__ volatile ("movq %5,%%r10 ; movq %6,%%r8 ; " __syscall
  81                 : "=a" (ret)
  82                 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
  83                   "g" (arg4), "g" (arg5)
  84                 : __syscall_clobber, "r10", "r8" );
  85
  86         return ret;
  87 }
  88
  89 static inline void trap_myself(void)
  90 {
  91         __asm("int3");
  92 }
  93
  94 static inline void remap_stack(long fd, unsigned long offset)
  95 {
  96         __asm__ volatile ("movq %4,%%r10 ; movq %5,%%r8 ; "
  97                           "movq %6, %%r9; " __syscall "; movq %7, %%rbx ; "
  98                           "movq %%rax, (%%rbx)":
  99                           : "a" (STUB_MMAP_NR), "D" (STUB_DATA),
 100                             "S" (UM_KERN_PAGE_SIZE),
 101                             "d" (PROT_READ | PROT_WRITE),
 102                             "g" (MAP_FIXED | MAP_SHARED), "g" (fd),
 103                             "g" (offset),
 104                             "i" (&((struct stub_data *) STUB_DATA)->err)
 105                           : __syscall_clobber, "r10", "r8", "r9" );
 106 }
 107
 108 #endif