1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1999 John D. Polstra 5 * Copyright (c) 1999,2001 Peter Wemm <peter@FreeBSD.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #ifndef _SYS_LINKER_SET_H_ 33 #define _SYS_LINKER_SET_H_ 34 35 #ifndef _SYS_CDEFS_H_ 36 #error this file needs sys/cdefs.h as a prerequisite 37 #endif 38 39 /* 40 * The following macros are used to declare global sets of objects, which 41 * are collected by the linker into a `linker_set' as defined below. 42 * For ELF, this is done by constructing a separate segment for each set. 43 */ 44 45 #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) 46 /* 47 * ELFv1 pointers to functions are actaully pointers to function 48 * descriptors. 49 * 50 * Move the symbol pointer from ".text" to ".data" segment, to make 51 * the GCC compiler happy: 52 */ 53 #define __MAKE_SET_CONST 54 #else 55 #define __MAKE_SET_CONST const 56 #endif 57 58 /* 59 * Private macros, not to be used outside this header file. 60 */ 61 #ifdef __GNUCLIKE___SECTION 62 63 /* 64 * The userspace address sanitizer inserts redzones around global variables, 65 * violating the assumption that linker set elements are packed. 66 */ 67 #ifdef _KERNEL 68 #define __NOASAN 69 #else 70 #define __NOASAN __nosanitizeaddress 71 #endif 72 73 #define __MAKE_SET_QV(set, sym, qv) \ 74 __WEAK(__CONCAT(__start_set_,set)); \ 75 __WEAK(__CONCAT(__stop_set_,set)); \ 76 static void const * qv \ 77 __NOASAN \ 78 __set_##set##_sym_##sym __section("set_" #set) \ 79 __used = &(sym) 80 #define __MAKE_SET(set, sym) __MAKE_SET_QV(set, sym, __MAKE_SET_CONST) 81 #else /* !__GNUCLIKE___SECTION */ 82 #error this file needs to be ported to your compiler 83 #endif /* __GNUCLIKE___SECTION */ 84 85 /* 86 * Public macros. 87 */ 88 #define TEXT_SET(set, sym) __MAKE_SET(set, sym) 89 #define DATA_SET(set, sym) __MAKE_SET(set, sym) 90 #define DATA_WSET(set, sym) __MAKE_SET_QV(set, sym, ) 91 #define BSS_SET(set, sym) __MAKE_SET(set, sym) 92 #define ABS_SET(set, sym) __MAKE_SET(set, sym) 93 #define SET_ENTRY(set, sym) __MAKE_SET(set, sym) 94 95 /* 96 * Initialize before referring to a given linker set. 97 */ 98 #define SET_DECLARE(set, ptype) \ 99 extern ptype __weak_symbol *__CONCAT(__start_set_,set); \ 100 extern ptype __weak_symbol *__CONCAT(__stop_set_,set) 101 102 #define SET_BEGIN(set) \ 103 (&__CONCAT(__start_set_,set)) 104 #define SET_LIMIT(set) \ 105 (&__CONCAT(__stop_set_,set)) 106 107 /* 108 * Iterate over all the elements of a set. 109 * 110 * Sets always contain addresses of things, and "pvar" points to words 111 * containing those addresses. Thus is must be declared as "type **pvar", 112 * and the address of each set item is obtained inside the loop by "*pvar". 113 */ 114 #define SET_FOREACH(pvar, set) \ 115 for (pvar = SET_BEGIN(set); pvar < SET_LIMIT(set); pvar++) 116 117 #define SET_ITEM(set, i) \ 118 ((SET_BEGIN(set))[i]) 119 120 /* 121 * Provide a count of the items in a set. 122 */ 123 #define SET_COUNT(set) \ 124 (SET_LIMIT(set) - SET_BEGIN(set)) 125 126 #endif /* _SYS_LINKER_SET_H_ */ 127