[linux-2.6-block.git] / include / linux / export.h

/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _LINUX_EXPORT_H
#define _LINUX_EXPORT_H

#include <linux/compiler.h>
#include <linux/linkage.h>
#include <linux/stringify.h>

/*
 * Export symbols from the kernel to modules.  Forked from module.h
 * to reduce the amount of pointless cruft we feed to gcc when only
 * exporting a simple symbol or two.
 *
 * Try not to add #includes here.  It slows compilation and makes kernel
 * hackers place grumpy comments in header files.
 */

/*
 * This comment block is used by fixdep. Please do not remove.
 *
 * When CONFIG_MODVERSIONS is changed from n to y, all source files having
 * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a
 * side effect of the *.o build rule.
 */

#ifndef __ASSEMBLY__
#ifdef MODULE
extern struct module __this_module;
#define THIS_MODULE (&__this_module)
#else
#define THIS_MODULE ((struct module *)0)
#endif
#endif /* __ASSEMBLY__ */

#ifdef CONFIG_64BIT
#define __EXPORT_SYMBOL_REF(sym)			\
	.balign 8				ASM_NL	\
	.quad sym
#else
#define __EXPORT_SYMBOL_REF(sym)			\
	.balign 4				ASM_NL	\
	.long sym
#endif

#define ___EXPORT_SYMBOL(sym, license, ns)		\
	.section ".export_symbol","a"		ASM_NL	\
	__export_symbol_##sym:			ASM_NL	\
		.asciz license			ASM_NL	\
		.asciz ns			ASM_NL	\
		__EXPORT_SYMBOL_REF(sym)	ASM_NL	\
	.previous

#if defined(__DISABLE_EXPORTS)

/*
 * Allow symbol exports to be disabled completely so that C code may
 * be reused in other execution contexts such as the UEFI stub or the
 * decompressor.
 */
#define __EXPORT_SYMBOL(sym, license, ns)

#elif defined(__GENKSYMS__)

#define __EXPORT_SYMBOL(sym, license, ns)	__GENKSYMS_EXPORT_SYMBOL(sym)

#elif defined(__ASSEMBLY__)

#define __EXPORT_SYMBOL(sym, license, ns) \
	___EXPORT_SYMBOL(sym, license, ns)

#else

#define __EXPORT_SYMBOL(sym, license, ns)			\
	extern typeof(sym) sym;					\
	__ADDRESSABLE(sym)					\
	asm(__stringify(___EXPORT_SYMBOL(sym, license, ns)))

#endif

#ifdef DEFAULT_SYMBOL_NAMESPACE
#define _EXPORT_SYMBOL(sym, license)	__EXPORT_SYMBOL(sym, license, __stringify(DEFAULT_SYMBOL_NAMESPACE))
#else
#define _EXPORT_SYMBOL(sym, license)	__EXPORT_SYMBOL(sym, license, "")
#endif

#define EXPORT_SYMBOL(sym)		_EXPORT_SYMBOL(sym, "")
#define EXPORT_SYMBOL_GPL(sym)		_EXPORT_SYMBOL(sym, "GPL")
#define EXPORT_SYMBOL_NS(sym, ns)	__EXPORT_SYMBOL(sym, "", __stringify(ns))
#define EXPORT_SYMBOL_NS_GPL(sym, ns)	__EXPORT_SYMBOL(sym, "GPL", __stringify(ns))

#endif /* _LINUX_EXPORT_H */
Commit	Line	Data
bf49d9dd	1	/* SPDX-License-Identifier: GPL-2.0-only */
f5016932 PG	2	#ifndef _LINUX_EXPORT_H
f5016932 PG	3	#define _LINUX_EXPORT_H
b67067f1	4
ddb5cdba MY	5	#include <linux/compiler.h>
ddb5cdba MY	6	#include <linux/linkage.h>
d143b9db GKH	7	#include <linux/stringify.h>
d143b9db GKH	8
f5016932 PG	9	/*
	10	* Export symbols from the kernel to modules. Forked from module.h
	11	* to reduce the amount of pointless cruft we feed to gcc when only
	12	* exporting a simple symbol or two.
	13	*
b92021b0 RR	14	* Try not to add #includes here. It slows compilation and makes kernel
b92021b0 RR	15	* hackers place grumpy comments in header files.
f5016932 PG	16	*/
f5016932 PG	17
7b453719 MY	18	/*
	19	* This comment block is used by fixdep. Please do not remove.
	20	*
	21	* When CONFIG_MODVERSIONS is changed from n to y, all source files having
	22	* EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a
	23	* side effect of the *.o build rule.
	24	*/
	25
b92021b0	26	#ifndef __ASSEMBLY__
f5016932 PG	27	#ifdef MODULE
	28	extern struct module __this_module;
	29	#define THIS_MODULE (&__this_module)
	30	#else
	31	#define THIS_MODULE ((struct module *)0)
	32	#endif
ddb5cdba	33	#endif /* __ASSEMBLY__ */
f5016932	34
ddb5cdba MY	35	#ifdef CONFIG_64BIT
	36	#define __EXPORT_SYMBOL_REF(sym) \
	37	.balign 8 ASM_NL \
	38	.quad sym
7290d580	39	#else
ddb5cdba MY	40	#define __EXPORT_SYMBOL_REF(sym) \
	41	.balign 4 ASM_NL \
	42	.long sym
7290d580 AB	43	#endif
7290d580 AB	44
5e9e95cc	45	#define ___EXPORT_SYMBOL(sym, license, ns) \
ddb5cdba MY	46	.section ".export_symbol","a" ASM_NL \
	47	__export_symbol_##sym: ASM_NL \
	48	.asciz license ASM_NL \
	49	.asciz ns ASM_NL \
	50	__EXPORT_SYMBOL_REF(sym) ASM_NL \
	51	.previous
	52
481461f5	53	#if defined(__DISABLE_EXPORTS)
f922c4ab AB	54
	55	/*
	56	* Allow symbol exports to be disabled completely so that C code may
	57	* be reused in other execution contexts such as the UEFI stub or the
	58	* decompressor.
	59	*/
8ed7e33a	60	#define __EXPORT_SYMBOL(sym, license, ns)
f922c4ab	61
5e9e95cc	62	#elif defined(__GENKSYMS__)
bbda5ec6	63
8ed7e33a	64	#define __EXPORT_SYMBOL(sym, license, ns) __GENKSYMS_EXPORT_SYMBOL(sym)
c1a95fda	65
5e9e95cc	66	#elif defined(__ASSEMBLY__)
ddb5cdba	67
5e9e95cc MY	68	#define __EXPORT_SYMBOL(sym, license, ns) \
5e9e95cc MY	69	___EXPORT_SYMBOL(sym, license, ns)
8651ec01	70
f2355416	71	#else
f2355416	72
5e9e95cc MY	73	#define __EXPORT_SYMBOL(sym, license, ns) \
	74	extern typeof(sym) sym; \
	75	__ADDRESSABLE(sym) \
	76	asm(__stringify(___EXPORT_SYMBOL(sym, license, ns)))
f5016932	77
481461f5	78	#endif
f5016932	79
8e2adc6a	80	#ifdef DEFAULT_SYMBOL_NAMESPACE
8ed7e33a	81	#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, __stringify(DEFAULT_SYMBOL_NAMESPACE))
c3a6cf19	82	#else
8ed7e33a	83	#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, "")
8e2adc6a MM	84	#endif
8e2adc6a MM	85
c3a6cf19	86	#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "")
ddb5cdba	87	#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "GPL")
d143b9db	88	#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", __stringify(ns))
ddb5cdba	89	#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "GPL", __stringify(ns))
f5016932 PG	90
f5016932 PG	91	#endif /* _LINUX_EXPORT_H */