linux/arch/um/sys-x86_64/syscall_table.c
Jeff Dike f87ea91d98 uml: redo the calculation of NR_syscalls
Redo the calculation of NR_syscalls since that disappeared from i386 and
use a similar mechanism on x86_64.

We now figure out the size of the system call table in arch code and stick
that in syscall_table_size.  arch/um/kernel/skas/syscall.c defines
NR_syscalls in terms of that since its the only thing that needs to know
how many system calls there are.

The old mechananism that was used on x86_64 is gone.

arch/um/include/sysdep-i386/syscalls.h got some formatting since I was
looking at it.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:32 -08:00

70 lines
1.9 KiB
C

/*
* System call table for UML/x86-64, copied from arch/x86_64/kernel/syscall.c
* with some changes for UML.
*/
#include <linux/linkage.h>
#include <linux/sys.h>
#include <linux/cache.h>
#include <kern_constants.h>
#define __NO_STUBS
/*
* Below you can see, in terms of #define's, the differences between the x86-64
* and the UML syscall table.
*/
/* Not going to be implemented by UML, since we have no hardware. */
#define stub_iopl sys_ni_syscall
#define sys_ioperm sys_ni_syscall
/*
* The UML TLS problem. Note that x86_64 does not implement this, so the below
* is needed only for the ia32 compatibility.
*/
/* On UML we call it this way ("old" means it's not mmap2) */
#define sys_mmap old_mmap
/*
* On x86-64 sys_uname is actually sys_newuname plus a compatibility trick.
* See arch/x86_64/kernel/sys_x86_64.c
*/
#define sys_uname sys_uname64
#define stub_clone sys_clone
#define stub_fork sys_fork
#define stub_vfork sys_vfork
#define stub_execve sys_execve
#define stub_rt_sigsuspend sys_rt_sigsuspend
#define stub_sigaltstack sys_sigaltstack
#define stub_rt_sigreturn sys_rt_sigreturn
#define __SYSCALL(nr, sym) extern asmlinkage void sym(void) ;
#undef _ASM_X86_64_UNISTD_H_
#include <asm-x86/unistd_64.h>
#undef __SYSCALL
#define __SYSCALL(nr, sym) [ nr ] = sym,
#undef _ASM_X86_64_UNISTD_H_
typedef void (*sys_call_ptr_t)(void);
extern void sys_ni_syscall(void);
/*
* We used to have a trick here which made sure that holes in the
* x86_64 table were filled in with sys_ni_syscall, but a comment in
* unistd_64.h says that holes aren't allowed, so the trick was
* removed.
* The trick looked like this
* [0 ... UM_NR_syscall_max] = &sys_ni_syscall
* before including unistd_64.h - the later initializations overwrote
* the sys_ni_syscall filler.
*/
sys_call_ptr_t sys_call_table[] __cacheline_aligned = {
#include <asm-x86/unistd_64.h>
};
int syscall_table_size = sizeof(sys_call_table);