[lttng-modules.git] / wrapper / kallsyms.h

/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
 *
 * wrapper/kallsyms.h
 *
 * wrapper around kallsyms_lookup_name. Implements arch-dependent code for
 * arches where the address of the start of the function body is different
 * from the pointer which can be used to call the function, e.g. ARM THUMB2.
 *
 * Copyright (C) 2011 Avik Sil (avik.sil@linaro.org)
 * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#ifndef _LTTNG_WRAPPER_KALLSYMS_H
#define _LTTNG_WRAPPER_KALLSYMS_H

#include <linux/kallsyms.h>
#include <linux/version.h>

/*
 * PowerPC ABIv1 needs KALLSYMS_ALL to get the function descriptor,
 * which is needed to perform the function call.
 */
#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF < 2)
# ifndef CONFIG_KALLSYMS_ALL
#  error "LTTng-modules requires CONFIG_KALLSYMS_ALL on PowerPC ABIv1"
# endif
#endif

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0))

unsigned long wrapper_kallsyms_lookup_name(const char *name);

#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0)) */

static inline
unsigned long wrapper_kallsyms_lookup_name(const char *name)
{
	return kallsyms_lookup_name(name);
}

#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0)) */

static inline
unsigned long kallsyms_lookup_funcptr(const char *name)
{
	unsigned long addr;

	addr = wrapper_kallsyms_lookup_name(name);
#ifdef CONFIG_ARM
#ifdef CONFIG_THUMB2_KERNEL
	if (addr)
		addr |= 1; /* set bit 0 in address for thumb mode */
#endif
#endif
	return addr;
}

static inline
unsigned long kallsyms_lookup_dataptr(const char *name)
{
	return wrapper_kallsyms_lookup_name(name);
}

#endif /* _LTTNG_WRAPPER_KALLSYMS_H */
Commit	Line	Data
	1	/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
	2	*
	3	* wrapper/kallsyms.h
	4	*
	5	* wrapper around kallsyms_lookup_name. Implements arch-dependent code for
	6	* arches where the address of the start of the function body is different
	7	* from the pointer which can be used to call the function, e.g. ARM THUMB2.
	8	*
	9	* Copyright (C) 2011 Avik Sil (avik.sil@linaro.org)
	10	* Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	11	*/
	12
	13	#ifndef _LTTNG_WRAPPER_KALLSYMS_H
	14	#define _LTTNG_WRAPPER_KALLSYMS_H
	15
	16	#include <linux/kallsyms.h>
	17	#include <linux/version.h>
	18
	19	/*
	20	* PowerPC ABIv1 needs KALLSYMS_ALL to get the function descriptor,
	21	* which is needed to perform the function call.
	22	*/
	23	#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) \|\| _CALL_ELF < 2)
	24	# ifndef CONFIG_KALLSYMS_ALL
	25	# error "LTTng-modules requires CONFIG_KALLSYMS_ALL on PowerPC ABIv1"
	26	# endif
	27	#endif
	28
	29	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0))
	30
	31	unsigned long wrapper_kallsyms_lookup_name(const char *name);
	32
	33	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0)) */
	34
	35	static inline
	36	unsigned long wrapper_kallsyms_lookup_name(const char *name)
	37	{
	38	return kallsyms_lookup_name(name);
	39	}
	40
	41	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0)) */
	42
	43	static inline
	44	unsigned long kallsyms_lookup_funcptr(const char *name)
	45	{
	46	unsigned long addr;
	47
	48	addr = wrapper_kallsyms_lookup_name(name);
	49	#ifdef CONFIG_ARM
	50	#ifdef CONFIG_THUMB2_KERNEL
	51	if (addr)
	52	addr \|= 1; /* set bit 0 in address for thumb mode */
	53	#endif
	54	#endif
	55	return addr;
	56	}
	57
	58	static inline
	59	unsigned long kallsyms_lookup_dataptr(const char *name)
	60	{
	61	return wrapper_kallsyms_lookup_name(name);
	62	}
	63
	64	#endif /* _LTTNG_WRAPPER_KALLSYMS_H */