From 72677cc3d8403da4b35c99617352bde347780222 Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Mon, 22 Jul 2002 17:10:30 +0000 Subject: Rework syscall handling. Rewrite syscall handlers for x86 and ARM. Prepare to kill the UNIFIED_SYSCALL option and instead have it be a per arch thing that is either enabled or not for that arch. -Erik --- libc/sysdeps/linux/i386/bits/syscalls.h | 265 +++++++++++++------------------- 1 file changed, 109 insertions(+), 156 deletions(-) (limited to 'libc/sysdeps/linux/i386/bits') diff --git a/libc/sysdeps/linux/i386/bits/syscalls.h b/libc/sysdeps/linux/i386/bits/syscalls.h index 940e9db50..cb70d15e3 100644 --- a/libc/sysdeps/linux/i386/bits/syscalls.h +++ b/libc/sysdeps/linux/i386/bits/syscalls.h @@ -1,147 +1,95 @@ -/* Unlike the asm/unistd.h kernel header file (which this is partly based on), - * this file must be able to cope with PIC and non-PIC code. For some arches - * there is no difference. For x86 (which has far too few registers) there is - * a difference. Regardless, including asm/unistd.h is hereby officially - * forbidden. Don't do it. It is bad for you. */ +#ifndef _BITS_SYSCALLS_H +#define _BITS_SYSCALLS_H +#ifndef _SYSCALL_H +# error "Never use directly; include instead." +#endif -#include +/* This includes the `__NR_' syscall numbers taken from the Linux kernel + * header files. It also defines the traditional `SYS_' macros for older + * programs. */ +#include -#ifndef __UCLIBC_USE_UNIFIED_SYSCALL__ +#ifndef __set_errno +# define __set_errno(val) (*__errno_location ()) = (val) +#endif -#undef __syscall_return -#define __syscall_return(type, res) \ -do { \ - if ((unsigned long)(res) >= (unsigned long)(-125)) { \ - errno = -(res); \ - res = -1; \ - } \ - return (type) (res); \ -} while (0) +/* + Some of the sneaky macros in the code were taken from + glibc-2.2.5/sysdeps/unix/sysv/linux/i386/sysdep.h +*/ + +#ifndef __ASSEMBLER__ + +/* We need some help from the assembler to generate optimal code. We + define some macros here which later will be used. */ +asm (".L__X'%ebx = 1\n\t" + ".L__X'%ecx = 2\n\t" + ".L__X'%edx = 2\n\t" + ".L__X'%eax = 3\n\t" + ".L__X'%esi = 3\n\t" + ".L__X'%edi = 3\n\t" + ".L__X'%ebp = 3\n\t" + ".L__X'%esp = 3\n\t" + ".macro bpushl name reg\n\t" + ".if 1 - \\name\n\t" + ".if 2 - \\name\n\t" + "pushl %ebx\n\t" + ".else\n\t" + "xchgl \\reg, %ebx\n\t" + ".endif\n\t" + ".endif\n\t" + ".endm\n\t" + ".macro bpopl name reg\n\t" + ".if 1 - \\name\n\t" + ".if 2 - \\name\n\t" + "popl %ebx\n\t" + ".else\n\t" + "xchgl \\reg, %ebx\n\t" + ".endif\n\t" + ".endif\n\t" + ".endm\n\t" + ".macro bmovl name reg\n\t" + ".if 1 - \\name\n\t" + ".if 2 - \\name\n\t" + "movl \\reg, %ebx\n\t" + ".endif\n\t" + ".endif\n\t" + ".endm\n\t"); #undef _syscall0 #define _syscall0(type,name) \ type name(void) \ { \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name)); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 0)); \ } - -#if defined(__PIC__) - -/* - * PIC uses %ebx, so we need to save it during system calls - */ - #undef _syscall1 #define _syscall1(type,name,type1,arg1) \ type name(type1 arg1) \ { \ -long __res; \ -__asm__ volatile ("push %%ebx; movl %2,%%ebx; int $0x80; pop %%ebx" \ - : "=a" (__res) \ - : "0" (__NR_##name),"r" ((long)(arg1))); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 1, arg1)); \ } #undef _syscall2 #define _syscall2(type,name,type1,arg1,type2,arg2) \ type name(type1 arg1,type2 arg2) \ { \ -long __res; \ -__asm__ volatile ("push %%ebx; movl %2,%%ebx; int $0x80; pop %%ebx" \ - : "=a" (__res) \ - : "0" (__NR_##name),"r" ((long)(arg1)),"c" ((long)(arg2))); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 2, arg1, arg2)); \ } #undef _syscall3 #define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \ type name(type1 arg1,type2 arg2,type3 arg3) \ { \ -long __res; \ -__asm__ volatile ("push %%ebx; movl %2,%%ebx; int $0x80; pop %%ebx" \ - : "=a" (__res) \ - : "0" (__NR_##name),"r" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3))); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 3, arg1, arg2, arg3)); \ } #undef _syscall4 #define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \ type name (type1 arg1, type2 arg2, type3 arg3, type4 arg4) \ { \ -long __res; \ -__asm__ volatile ("push %%ebx; movl %2,%%ebx; int $0x80; pop %%ebx" \ - : "=a" (__res) \ - : "0" (__NR_##name),"r" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3)),"S" ((long)(arg4))); \ -__syscall_return(type,__res); \ -} - -#undef _syscall5 -#define _syscall5(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4, \ - type5,arg5) \ -type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5) \ -{ \ -long __res; \ -__asm__ volatile ("push %%ebx; movl %2,%%ebx; int $0x80; pop %%ebx" \ - : "=a" (__res) \ - : "0" (__NR_##name),"m" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3)),"S" ((long)(arg4)),"D" ((long)(arg5))); \ -__syscall_return(type,__res); \ -} - -#else /* not doing __PIC__ */ - -#undef _syscall1 -#define _syscall1(type,name,type1,arg1) \ -type name(type1 arg1) \ -{ \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name),"b" ((long)(arg1))); \ -__syscall_return(type,__res); \ -} - -#undef _syscall2 -#define _syscall2(type,name,type1,arg1,type2,arg2) \ -type name(type1 arg1,type2 arg2) \ -{ \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2))); \ -__syscall_return(type,__res); \ -} - -#undef _syscall3 -#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \ -type name(type1 arg1,type2 arg2,type3 arg3) \ -{ \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3))); \ -__syscall_return(type,__res); \ -} - -#undef _syscall4 -#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \ -type name (type1 arg1, type2 arg2, type3 arg3, type4 arg4) \ -{ \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3)),"S" ((long)(arg4))); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 4, arg1, arg2, arg3, arg4)); \ } #undef _syscall5 @@ -149,50 +97,55 @@ __syscall_return(type,__res); \ type5,arg5) \ type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5) \ { \ -long __res; \ -__asm__ volatile ("int $0x80" \ - : "=a" (__res) \ - : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \ - "d" ((long)(arg3)),"S" ((long)(arg4)),"D" ((long)(arg5))); \ -__syscall_return(type,__res); \ +return (type) (INLINE_SYSCALL(name, 5, arg1, arg2, arg3, arg4, arg5)); \ } - -#endif /* __PIC__ */ - - -#else - -#define unified_syscall_body(name) \ -__asm__ ( \ -".text\n.align 4\n.global "###name"\n.type "###name",@function\n" \ -#name":\nmovb $"__STR_NR_##name \ -",%al;\n jmp __uClibc_syscall\n.Lfe1"###name":\n.size "###name \ -",.Lfe1"###name"-"###name \ -) - -#undef _syscall0 -#define _syscall0(type,name) \ -unified_syscall_body(name) - -#undef _syscall1 -#define _syscall1(type,name,type1,arg1) \ -unified_syscall_body(name) - -#undef _syscall2 -#define _syscall2(type,name,type1,arg1,type2,arg2) \ -unified_syscall_body(name) - -#undef _syscall3 -#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \ -unified_syscall_body(name) - -#undef _syscall4 -#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \ -unified_syscall_body(name) - -#undef _syscall5 -#define _syscall5(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4,type5,arg5) \ -unified_syscall_body(name) - -#endif +#define INLINE_SYSCALL(name, nr, args...) \ + ({ \ + unsigned int resultvar; \ + asm volatile ( \ + LOADARGS_##nr \ + "movl %1, %%eax\n\t" \ + "int $0x80\n\t" \ + RESTOREARGS_##nr \ + : "=a" (resultvar) \ + : "i" (__NR_##name) ASMFMT_##nr(args) : "memory", "cc"); \ + if (resultvar >= 0xfffff001) \ + { \ + __set_errno (-resultvar); \ + resultvar = 0xffffffff; \ + } \ + (int) resultvar; }) + +#define LOADARGS_0 +#define LOADARGS_1 \ + "bpushl .L__X'%k2, %k2\n\t" \ + "bmovl .L__X'%k2, %k2\n\t" +#define LOADARGS_2 LOADARGS_1 +#define LOADARGS_3 LOADARGS_1 +#define LOADARGS_4 LOADARGS_1 +#define LOADARGS_5 LOADARGS_1 + +#define RESTOREARGS_0 +#define RESTOREARGS_1 \ + "bpopl .L__X'%k2, %k2\n\t" +#define RESTOREARGS_2 RESTOREARGS_1 +#define RESTOREARGS_3 RESTOREARGS_1 +#define RESTOREARGS_4 RESTOREARGS_1 +#define RESTOREARGS_5 RESTOREARGS_1 + +#define ASMFMT_0() +#define ASMFMT_1(arg1) \ + , "acdSD" (arg1) +#define ASMFMT_2(arg1, arg2) \ + , "adCD" (arg1), "c" (arg2) +#define ASMFMT_3(arg1, arg2, arg3) \ + , "aCD" (arg1), "c" (arg2), "d" (arg3) +#define ASMFMT_4(arg1, arg2, arg3, arg4) \ + , "aD" (arg1), "c" (arg2), "d" (arg3), "S" (arg4) +#define ASMFMT_5(arg1, arg2, arg3, arg4, arg5) \ + , "a" (arg1), "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5) + + +#endif /* __ASSEMBLER__ */ +#endif /* _BITS_SYSCALLS_H */ -- cgit v1.2.3