xref: /linux/include/linux/export-internal.h (revision 06d07429858317ded2db7986113a9e0129cd599b)
1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   * Please do not include this explicitly.
4   * This is used by C files generated by modpost.
5   */
6  
7  #ifndef __LINUX_EXPORT_INTERNAL_H__
8  #define __LINUX_EXPORT_INTERNAL_H__
9  
10  #include <linux/compiler.h>
11  #include <linux/types.h>
12  
13  #if defined(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)
14  /*
15   * relative reference: this reduces the size by half on 64-bit architectures,
16   * and eliminates the need for absolute relocations that require runtime
17   * processing on relocatable kernels.
18   */
19  #define __KSYM_ALIGN		".balign 4"
20  #define __KSYM_REF(sym)		".long " #sym "- ."
21  #elif defined(CONFIG_64BIT)
22  #define __KSYM_ALIGN		".balign 8"
23  #define __KSYM_REF(sym)		".quad " #sym
24  #else
25  #define __KSYM_ALIGN		".balign 4"
26  #define __KSYM_REF(sym)		".long " #sym
27  #endif
28  
29  /*
30   * For every exported symbol, do the following:
31   *
32   * - Put the name of the symbol and namespace (empty string "" for none) in
33   *   __ksymtab_strings.
34   * - Place a struct kernel_symbol entry in the __ksymtab section.
35   *
36   * Note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)
37   * section flag requires it. Use '%progbits' instead of '@progbits' since the
38   * former apparently works on all arches according to the binutils source.
39   */
40  #define __KSYMTAB(name, sym, sec, ns)						\
41  	asm("	.section \"__ksymtab_strings\",\"aMS\",%progbits,1"	"\n"	\
42  	    "__kstrtab_" #name ":"					"\n"	\
43  	    "	.asciz \"" #name "\""					"\n"	\
44  	    "__kstrtabns_" #name ":"					"\n"	\
45  	    "	.asciz \"" ns "\""					"\n"	\
46  	    "	.previous"						"\n"	\
47  	    "	.section \"___ksymtab" sec "+" #name "\", \"a\""	"\n"	\
48  		__KSYM_ALIGN						"\n"	\
49  	    "__ksymtab_" #name ":"					"\n"	\
50  		__KSYM_REF(sym)						"\n"	\
51  		__KSYM_REF(__kstrtab_ ##name)				"\n"	\
52  		__KSYM_REF(__kstrtabns_ ##name)				"\n"	\
53  	    "	.previous"						"\n"	\
54  	)
55  
56  #if defined(CONFIG_PARISC) && defined(CONFIG_64BIT)
57  #define KSYM_FUNC(name)		P%name
58  #else
59  #define KSYM_FUNC(name)		name
60  #endif
61  
62  #define KSYMTAB_FUNC(name, sec, ns)	__KSYMTAB(name, KSYM_FUNC(name), sec, ns)
63  #define KSYMTAB_DATA(name, sec, ns)	__KSYMTAB(name, name, sec, ns)
64  
65  #define SYMBOL_CRC(sym, crc, sec)   \
66  	asm(".section \"___kcrctab" sec "+" #sym "\",\"a\""	"\n" \
67  	    ".balign 4"						"\n" \
68  	    "__crc_" #sym ":"					"\n" \
69  	    ".long " #crc					"\n" \
70  	    ".previous"						"\n")
71  
72  #endif /* __LINUX_EXPORT_INTERNAL_H__ */
73