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#ifndef _BITS_SYSCALLS_H
#define _BITS_SYSCALLS_H
#ifndef _SYSCALL_H
# error "Never use <bits/syscalls.h> directly; include <sys/syscall.h> instead."
#endif
/* m68k headers does stupid stuff with __NR_iopl / __NR_vm86:
* #define __NR_iopl not supported
* #define __NR_vm86 not supported
*/
#undef __NR_iopl
#undef __NR_vm86
#ifndef __ASSEMBLER__
/* Linux takes system call arguments in registers:
syscall number %d0 call-clobbered
arg 1 %d1 call-clobbered
arg 2 %d2 call-saved
arg 3 %d3 call-saved
arg 4 %d4 call-saved
arg 5 %d5 call-saved
arg 6 %a0 call-clobbered
The stack layout upon entering the function is:
24(%sp) Arg# 6
20(%sp) Arg# 5
16(%sp) Arg# 4
12(%sp) Arg# 3
8(%sp) Arg# 2
4(%sp) Arg# 1
(%sp) Return address
(Of course a function with say 3 arguments does not have entries for
arguments 4 and 5.)
Separate move's are faster than movem, but need more space. Since
speed is more important, we don't use movem. Since %a0 and %a1 are
scratch registers, we can use them for saving as well. */
/* Define a macro which expands inline into the wrapper code for a system
call. This use is for internal calls that do not need to handle errors
normally. It will never touch errno. This returns just what the kernel
gave back. */
#define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ unsigned int _sys_result; \
{ \
/* Load argument values in temporary variables
to perform side effects like function calls
before the call used registers are set. */ \
LOAD_ARGS_##nr (args) \
LOAD_REGS_##nr \
register int _d0 __asm__ ("%d0") = name; \
__asm__ __volatile__ ("trap #0" \
: "=d" (_d0) \
: "0" (_d0) ASM_ARGS_##nr \
: "memory"); \
_sys_result = _d0; \
} \
(int) _sys_result; })
#define LOAD_ARGS_0()
#define LOAD_REGS_0
#define ASM_ARGS_0
#define LOAD_ARGS_1(a1) \
LOAD_ARGS_0 () \
int __arg1 = (int) (a1);
#define LOAD_REGS_1 \
register int _d1 __asm__ ("d1") = __arg1; \
LOAD_REGS_0
#define ASM_ARGS_1 ASM_ARGS_0, "d" (_d1)
#define LOAD_ARGS_2(a1, a2) \
LOAD_ARGS_1 (a1) \
int __arg2 = (int) (a2);
#define LOAD_REGS_2 \
register int _d2 __asm__ ("d2") = __arg2; \
LOAD_REGS_1
#define ASM_ARGS_2 ASM_ARGS_1, "d" (_d2)
#define LOAD_ARGS_3(a1, a2, a3) \
LOAD_ARGS_2 (a1, a2) \
int __arg3 = (int) (a3);
#define LOAD_REGS_3 \
register int _d3 __asm__ ("d3") = __arg3; \
LOAD_REGS_2
#define ASM_ARGS_3 ASM_ARGS_2, "d" (_d3)
#define LOAD_ARGS_4(a1, a2, a3, a4) \
LOAD_ARGS_3 (a1, a2, a3) \
int __arg4 = (int) (a4);
#define LOAD_REGS_4 \
register int _d4 __asm__ ("d4") = __arg4; \
LOAD_REGS_3
#define ASM_ARGS_4 ASM_ARGS_3, "d" (_d4)
#define LOAD_ARGS_5(a1, a2, a3, a4, a5) \
LOAD_ARGS_4 (a1, a2, a3, a4) \
int __arg5 = (int) (a5);
#define LOAD_REGS_5 \
register int _d5 __asm__ ("d5") = __arg5; \
LOAD_REGS_4
#define ASM_ARGS_5 ASM_ARGS_4, "d" (_d5)
#define LOAD_ARGS_6(a1, a2, a3, a4, a5, a6) \
LOAD_ARGS_5 (a1, a2, a3, a4, a5) \
int __arg6 = (int) (a6);
#define LOAD_REGS_6 \
register int _a0 __asm__ ("a0") = __arg6; \
LOAD_REGS_5
#define ASM_ARGS_6 ASM_ARGS_5, "a" (_a0)
#endif /* __ASSEMBLER__ */
#endif /* _BITS_SYSCALLS_H */
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