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 "stub-data.h"
  13 #include "kern_constants.h"
  14 #include "uml-config.h"
  15
  16 extern void stub_segv_handler(int sig);
  17 extern 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
  26 static 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
  37 static 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
  48 static 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
  60 static 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
  74 static 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
  88 static inline void trap_myself(void)
  89 {
  90         __asm("int3");
  91 }
  92
  93 static 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" (UML_CONFIG_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 *) UML_CONFIG_STUB_DATA)->err)
 104                           : __syscall_clobber, "r10", "r8", "r9" );
 105 }
 106
 107 #endif