/* $OpenBSD: SYS.h,v 1.16 2024/03/27 20:03:29 miod Exp $ */ /*- * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * William Jolitz. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)SYS.h 5.5 (Berkeley) 5/7/91 * $NetBSD: SYS.h,v 1.9 2006/01/06 06:19:20 uwe Exp $ */ #include <machine/asm.h> #include <sys/syscall.h> /* * We need to offset the TCB pointer (in register gbr) by this much: * offsetof(struct tib, tib_errno) - offsetof(struct tib, __tib_tcb) * That's negative on a variant I arch like sh, but you can't directly * load negative numbers or use them as displacements. Ha! So this is the * negative of the real value and we'll explicitly subtract it in the asm */ #define TCB_OFFSET_ERRNO_NEG 8 /* * We define a hidden alias with the prefix "_libc_" for each global symbol * that may be used internally. By referencing _libc_x instead of x, other * parts of libc prevent overriding by the application and avoid unnecessary * relocations. */ #define _HIDDEN(x) _libc_##x #define _HIDDEN_ALIAS(x,y) \ STRONG_ALIAS(_HIDDEN(x),y); \ .hidden _HIDDEN(x) #define _HIDDEN_FALIAS(x,y) \ _HIDDEN_ALIAS(x,y); \ .type _HIDDEN(x),@function /* * For functions implemented in ASM that aren't syscalls. * END_STRONG(x) Like DEF_STRONG() in C; for standard/reserved C names * END_WEAK(x) Like DEF_WEAK() in C; for non-ISO C names */ #define END_STRONG(x) SET_ENTRY_SIZE(x); \ _HIDDEN_FALIAS(x,x); \ SET_ENTRY_SIZE(_HIDDEN(x)) #define END_WEAK(x) END_STRONG(x); .weak x #define SYSENTRY(x) \ WEAK_ALIAS(x,_thread_sys_ ## x); \ ENTRY(_thread_sys_ ## x) #define SYSENTRY_HIDDEN(x) \ ENTRY(_thread_sys_ ## x) #define PINSYSCALL(sysno, label) \ .pushsection .openbsd.syscalls,"",@progbits; \ .p2align 2; \ .long label; \ .long sysno; \ .popsection; #ifdef __ASSEMBLER__ /* * If the system call number fits in a 8-bit signed value (i.e. fits in 7 bits), * then we can use the #imm8 addressing mode. Otherwise, we'll load the number * from memory at the end of the system call wrapper. */ .macro systrap num .iflt \num - 128 mov # \num, r0 97: trapa #0x80 PINSYSCALL(\num, 97b) .else mov.l 903f, r0 97: trapa #0x80 PINSYSCALL(\num, 97b) .endif .endm .macro systrap_data num .iflt \num - 128 .else .text .align 2 903: .long \num .endif .endm .macro syscall_error num .ifeq \num - SYS_lseek mov #-1, r1 .endif rts mov #-1, r0 .endm #endif #define SYSTRAP(x) \ systrap SYS_ ## x #define _SYSCALL_NOERROR(x,y) \ SYSENTRY(x); \ SYSTRAP(y) #define _SYSCALL_HIDDEN_NOERROR(x,y) \ SYSENTRY_HIDDEN(x); \ SYSTRAP(y) #define SET_ERRNO_AND_RETURN(y) \ stc gbr,r1; \ mov #TCB_OFFSET_ERRNO_NEG,r2; \ sub r2,r1; \ mov.l r0,@r1; \ syscall_error SYS_ ## y #define _SYSCALL(x,y) \ .text; \ 911: SET_ERRNO_AND_RETURN(y); \ _SYSCALL_NOERROR(x,y); \ bf 911b #define _SYSCALL_HIDDEN(x,y) \ .text; \ 911: SET_ERRNO_AND_RETURN(y); \ _SYSCALL_HIDDEN_NOERROR(x,y); \ bf 911b #define __END_HIDDEN(x,y) \ systrap_data SYS_ ## y; \ SET_ENTRY_SIZE(_thread_sys_ ## x); \ _HIDDEN_FALIAS(x,_thread_sys_ ## x); \ SET_ENTRY_SIZE(_HIDDEN(x)) #define __END(x,y) \ __END_HIDDEN(x,y); SET_ENTRY_SIZE(x) #define SYSCALL_NOERROR(x) \ _SYSCALL_NOERROR(x,x) #define SYSCALL(x) \ _SYSCALL(x,x) #define PSEUDO_NOERROR(x,y) \ _SYSCALL_NOERROR(x,y); \ rts; \ nop; \ __END(x,y) #define PSEUDO(x,y) \ _SYSCALL(x,y); \ rts; \ nop; \ __END(x,y) #define PSEUDO_HIDDEN(x,y) \ _SYSCALL_HIDDEN(x,y); \ rts; \ nop; \ __END_HIDDEN(x,y) #define RSYSCALL_NOERROR(x) PSEUDO_NOERROR(x,x) #define RSYSCALL(x) PSEUDO(x,x) #define RSYSCALL_HIDDEN(x) PSEUDO_HIDDEN(x,x) #define SYSCALL_END(x) __END(x,x) #define SYSCALL_END_HIDDEN(x) __END_HIDDEN(x,x)
