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 /* 36 * The following macros are used to declare global sets of objects, which 37 * are collected by the linker into a `linker_set' as defined below. 38 * For ELF, this is done by constructing a separate segment for each set. 39 */ 40 41 #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) 42 /* 43 * ELFv1 pointers to functions are actaully pointers to function 44 * descriptors. 45 * 46 * Move the symbol pointer from ".text" to ".data" segment, to make 47 * the GCC compiler happy: 48 */ 49 #define __MAKE_SET_CONST 50 #else 51 #define __MAKE_SET_CONST const 52 #endif 53 54 /* 55 * Private macros, not to be used outside this header file. 56 */ 57 58 /* 59 * The userspace address sanitizer inserts redzones around global variables, 60 * violating the assumption that linker set elements are packed. 61 */ 62 #ifdef _KERNEL 63 #define __NOASAN 64 #else 65 #define __NOASAN __nosanitizeaddress 66 #endif 67 68 #define __MAKE_SET_QV(set, sym, qv) \ 69 __WEAK(__CONCAT(__start_set_,set)); \ 70 __WEAK(__CONCAT(__stop_set_,set)); \ 71 static void const * qv \ 72 __NOASAN \ 73 __set_##set##_sym_##sym __section("set_" #set) \ 74 __used = &(sym) 75 #define __MAKE_SET(set, sym) __MAKE_SET_QV(set, sym, __MAKE_SET_CONST) 76 77 /* 78 * Public macros. 79 */ 80 #define TEXT_SET(set, sym) __MAKE_SET(set, sym) 81 #define DATA_SET(set, sym) __MAKE_SET(set, sym) 82 #define DATA_WSET(set, sym) __MAKE_SET_QV(set, sym, ) 83 #define BSS_SET(set, sym) __MAKE_SET(set, sym) 84 #define ABS_SET(set, sym) __MAKE_SET(set, sym) 85 #define SET_ENTRY(set, sym) __MAKE_SET(set, sym) 86 87 /* 88 * Initialize before referring to a given linker set. 89 */ 90 #define SET_DECLARE(set, ptype) \ 91 extern ptype __weak_symbol *__CONCAT(__start_set_,set); \ 92 extern ptype __weak_symbol *__CONCAT(__stop_set_,set) 93 94 #define SET_BEGIN(set) \ 95 (&__CONCAT(__start_set_,set)) 96 #define SET_LIMIT(set) \ 97 (&__CONCAT(__stop_set_,set)) 98 99 /* 100 * Iterate over all the elements of a set. 101 * 102 * Sets always contain addresses of things, and "pvar" points to words 103 * containing those addresses. Thus is must be declared as "type **pvar", 104 * and the address of each set item is obtained inside the loop by "*pvar". 105 */ 106 #define SET_FOREACH(pvar, set) \ 107 for (pvar = SET_BEGIN(set); pvar < SET_LIMIT(set); pvar++) 108 109 #define SET_ITEM(set, i) \ 110 ((SET_BEGIN(set))[i]) 111 112 /* 113 * Provide a count of the items in a set. 114 */ 115 #define SET_COUNT(set) \ 116 (SET_LIMIT(set) - SET_BEGIN(set)) 117 118 #endif /* _SYS_LINKER_SET_H_ */ 119