1 /* $OpenBSD: SYS.h,v 1.23 2019/07/14 03:36:37 guenther Exp $ */ 2 /*- 3 * Copyright (c) 1994 4 * Andrew Cagney. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Ralph Campbell. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: @(#)SYS.h 8.1 (Berkeley) 6/4/93 38 */ 39 40 #include <sys/syscall.h> 41 42 /* r0 will be a non zero errno if there was an error, while r3/r4 will 43 contain the return value */ 44 45 #include "machine/asm.h" 46 47 48 /* offsetof(struct tib, tib_errno) - offsetof(struct tib, __tib_tcb) */ 49 #define TCB_OFFSET_ERRNO (-8) 50 /* from <powerpc/tcb.h>: TCB address == %r2 - TCB_OFFSET */ 51 #define TCB_OFFSET 0x7000 52 53 /* offset of errno from %r2 */ 54 #define R2_OFFSET_ERRNO (-TCB_OFFSET + TCB_OFFSET_ERRNO) 55 56 /* 57 * We define a hidden alias with the prefix "_libc_" for each global symbol 58 * that may be used internally. By referencing _libc_x instead of x, other 59 * parts of libc prevent overriding by the application and avoid unnecessary 60 * relocations. 61 */ 62 #define _HIDDEN(x) _libc_##x 63 #define _HIDDEN_ALIAS(x,y) \ 64 STRONG_ALIAS(_HIDDEN(x),y); \ 65 .hidden _HIDDEN(x) 66 #define _HIDDEN_FALIAS(x,y) \ 67 _HIDDEN_ALIAS(x,y); \ 68 .type _HIDDEN(x),@function 69 70 /* 71 * For functions implemented in ASM that aren't syscalls. 72 * END_STRONG(x) Like DEF_STRONG() in C; for standard/reserved C names 73 * END_WEAK(x) Like DEF_WEAK() in C; for non-ISO C names 74 */ 75 #define END_STRONG(x) END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x)) 76 #define END_WEAK(x) END_STRONG(x); .weak x 77 78 79 #define _CONCAT(x,y) x##y 80 #define PSEUDO_PREFIX(p,x,y) \ 81 ENTRY(p##x) \ 82 li 0, SYS_##y ; \ 83 /* sc */ 84 #define PSEUDO_SUFFIX cmpwi 0, 0 ; \ 85 beqlr+ ; \ 86 stw 0, R2_OFFSET_ERRNO(2); \ 87 li 3, -1; \ 88 li 4, -1; /* for __syscall(lseek) */ \ 89 blr 90 91 #define PSEUDO_NOERROR_SUFFIX blr 92 93 #define __END_HIDDEN(p,x) END(p##x); \ 94 _HIDDEN_FALIAS(x,p##x); \ 95 END(_HIDDEN(x)) 96 #define __END(p,x) __END_HIDDEN(p,x); END(x) 97 98 99 #define ALIAS(x,y) WEAK_ALIAS(y,_CONCAT(x,y)); 100 101 #define PREFIX_HIDDEN(x) PSEUDO_PREFIX(_thread_sys_,x,x) 102 #define PREFIX(x) ALIAS(_thread_sys_,x) \ 103 PREFIX_HIDDEN(x) 104 #define PSEUDO_NOERROR(x,y) ALIAS(_thread_sys_,x) \ 105 PSEUDO_PREFIX(_thread_sys_,x,y) ; \ 106 sc ; \ 107 PSEUDO_NOERROR_SUFFIX; \ 108 __END(_thread_sys_,x) 109 110 #define PSEUDO_HIDDEN(x,y) PSEUDO_PREFIX(_thread_sys_,x,y) ; \ 111 sc ; \ 112 PSEUDO_SUFFIX; \ 113 __END_HIDDEN(_thread_sys_,x) 114 #define PSEUDO(x,y) ALIAS(_thread_sys_,x) \ 115 PSEUDO_HIDDEN(x,y); \ 116 END(x) 117 118 #define RSYSCALL(x) PSEUDO(x,x) 119 #define RSYSCALL_HIDDEN(x) PSEUDO_HIDDEN(x,x) 120 #define SYSCALL_END_HIDDEN(x) __END_HIDDEN(_thread_sys_,x) 121 #define SYSCALL_END(x) __END(_thread_sys_,x) 122 123