arch/um/include/sysdep-i386/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/ptrace.h>
  11 #include <asm/unistd.h>
  12 #include <asm/page.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 EAX
  21 #define STUB_MMAP_NR __NR_mmap2
  22 #define MMAP_OFFSET(o) ((o) >> PAGE_SHIFT)
  23
  24 static inline long stub_syscall0(long syscall)
  25 {
  26         long ret;
  27
  28         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall));
  29
  30         return ret;
  31 }
  32
  33 static inline long stub_syscall1(long syscall, long arg1)
  34 {
  35         long ret;
  36
  37         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1));
  38
  39         return ret;
  40 }
  41
  42 static inline long stub_syscall2(long syscall, long arg1, long arg2)
  43 {
  44         long ret;
  45
  46         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
  47                         "c" (arg2));
  48
  49         return ret;
  50 }
  51
  52 static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
  53 {
  54         long ret;
  55
  56         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
  57                         "c" (arg2), "d" (arg3));
  58
  59         return ret;
  60 }
  61
  62 static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
  63                                  long arg4)
  64 {
  65         long ret;
  66
  67         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
  68                         "c" (arg2), "d" (arg3), "S" (arg4));
  69
  70         return ret;
  71 }
  72
  73 static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
  74                                  long arg4, long arg5)
  75 {
  76         long ret;
  77
  78         __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
  79                         "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5));
  80
  81         return ret;
  82 }
  83
  84 static inline void trap_myself(void)
  85 {
  86         __asm("int3");
  87 }
  88
  89 static inline void remap_stack(int fd, unsigned long offset)
  90 {
  91         __asm__ volatile ("movl %%eax,%%ebp ; movl %0,%%eax ; int $0x80 ;"
  92                           "movl %7, %%ebx ; movl %%eax, (%%ebx)"
  93                           : : "g" (STUB_MMAP_NR), "b" (UML_CONFIG_STUB_DATA),
  94                             "c" (UM_KERN_PAGE_SIZE),
  95                             "d" (PROT_READ | PROT_WRITE),
  96                             "S" (MAP_FIXED | MAP_SHARED), "D" (fd),
  97                             "a" (offset),
  98                             "i" (&((struct stub_data *) UML_CONFIG_STUB_DATA)->err)
  99                           : "memory");
 100 }
 101
 102 #endif