arch/x86/um/sys_call_table_64.c

   1 /*
   2  * System call table for UML/x86-64, copied from arch/x86_64/kernel/syscall.c
   3  * with some changes for UML.
   4  */
   5
   6 #include <linux/linkage.h>
   7 #include <linux/sys.h>
   8 #include <linux/cache.h>
   9
  10 #define __NO_STUBS
  11
  12 /*
  13  * Below you can see, in terms of #define's, the differences between the x86-64
  14  * and the UML syscall table.
  15  */
  16
  17 /* Not going to be implemented by UML, since we have no hardware. */
  18 #define stub_iopl sys_ni_syscall
  19 #define sys_ioperm sys_ni_syscall
  20
  21 /*
  22  * The UML TLS problem. Note that x86_64 does not implement this, so the below
  23  * is needed only for the ia32 compatibility.
  24  */
  25
  26 /* On UML we call it this way ("old" means it's not mmap2) */
  27 #define sys_mmap old_mmap
  28
  29 #define stub_clone sys_clone
  30 #define stub_fork sys_fork
  31 #define stub_vfork sys_vfork
  32 #define stub_execve sys_execve
  33 #define stub_rt_sigsuspend sys_rt_sigsuspend
  34 #define stub_sigaltstack sys_sigaltstack
  35 #define stub_rt_sigreturn sys_rt_sigreturn
  36
  37 #define __SYSCALL(nr, sym) extern asmlinkage void sym(void) ;
  38 #undef _ASM_X86_UNISTD_64_H
  39 #include "../../x86/include/asm/unistd_64.h"
  40
  41 #undef __SYSCALL
  42 #define __SYSCALL(nr, sym) [ nr ] = sym,
  43 #undef _ASM_X86_UNISTD_64_H
  44
  45 typedef void (*sys_call_ptr_t)(void);
  46
  47 extern void sys_ni_syscall(void);
  48
  49 /*
  50  * We used to have a trick here which made sure that holes in the
  51  * x86_64 table were filled in with sys_ni_syscall, but a comment in
  52  * unistd_64.h says that holes aren't allowed, so the trick was
  53  * removed.
  54  * The trick looked like this
  55  *      [0 ... UM_NR_syscall_max] = &sys_ni_syscall
  56  * before including unistd_64.h - the later initializations overwrote
  57  * the sys_ni_syscall filler.
  58  */
  59
  60 sys_call_ptr_t sys_call_table[] __cacheline_aligned = {
  61 #include <asm/unistd_64.h>
  62 };
  63
  64 int syscall_table_size = sizeof(sys_call_table);