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

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * 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 <lttng/kernel-version.h>

/* CONFIG_PPC64_ELF_ABI_V1/V2 were introduced in v5.19 */
#if defined(CONFIG_PPC64_ELF_ABI_V2) || (defined(CONFIG_PPC64) && defined(CONFIG_CPU_LITTLE_ENDIAN))
#define LTTNG_CONFIG_PPC64_ELF_ABI_V2
#endif
#if defined(CONFIG_PPC64_ELF_ABI_V1) || (defined(CONFIG_PPC64) && defined(CONFIG_CPU_BIG_ENDIAN))
#define LTTNG_CONFIG_PPC64_ELF_ABI_V1
#endif

/*
 * PowerPC ABIv1 needs KALLSYMS_ALL to get the function descriptor,
 * which is needed to perform the function call.
 */
#ifdef LTTNG_CONFIG_PPC64_ELF_ABI_V1
# ifndef CONFIG_KALLSYMS_ALL
#  error "LTTng-modules requires CONFIG_KALLSYMS_ALL on PowerPC ABIv1"
# endif
#endif

#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,7,0))

unsigned long wrapper_kallsyms_lookup_name(const char *name);

#else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,7,0)) */

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

#endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_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-only or LGPL-2.1-only)
	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 <lttng/kernel-version.h>
	18
	19	/* CONFIG_PPC64_ELF_ABI_V1/V2 were introduced in v5.19 */
	20	#if defined(CONFIG_PPC64_ELF_ABI_V2) \|\| (defined(CONFIG_PPC64) && defined(CONFIG_CPU_LITTLE_ENDIAN))
	21	#define LTTNG_CONFIG_PPC64_ELF_ABI_V2
	22	#endif
	23	#if defined(CONFIG_PPC64_ELF_ABI_V1) \|\| (defined(CONFIG_PPC64) && defined(CONFIG_CPU_BIG_ENDIAN))
	24	#define LTTNG_CONFIG_PPC64_ELF_ABI_V1
	25	#endif
	26
	27	/*
	28	* PowerPC ABIv1 needs KALLSYMS_ALL to get the function descriptor,
	29	* which is needed to perform the function call.
	30	*/
	31	#ifdef LTTNG_CONFIG_PPC64_ELF_ABI_V1
	32	# ifndef CONFIG_KALLSYMS_ALL
	33	# error "LTTng-modules requires CONFIG_KALLSYMS_ALL on PowerPC ABIv1"
	34	# endif
	35	#endif
	36
	37	#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,7,0))
	38
	39	unsigned long wrapper_kallsyms_lookup_name(const char *name);
	40
	41	#else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,7,0)) */
	42
	43	static inline
	44	unsigned long wrapper_kallsyms_lookup_name(const char *name)
	45	{
	46	return kallsyms_lookup_name(name);
	47	}
	48
	49	#endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,7,0)) */
	50
	51	static inline
	52	unsigned long kallsyms_lookup_funcptr(const char *name)
	53	{
	54	unsigned long addr;
	55
	56	addr = wrapper_kallsyms_lookup_name(name);
	57	#ifdef CONFIG_ARM
	58	#ifdef CONFIG_THUMB2_KERNEL
	59	if (addr)
	60	addr \|= 1; /* set bit 0 in address for thumb mode */
	61	#endif
	62	#endif
	63	return addr;
	64	}
	65
	66	static inline
	67	unsigned long kallsyms_lookup_dataptr(const char *name)
	68	{
	69	return wrapper_kallsyms_lookup_name(name);
	70	}
	71
	72	#endif /* _LTTNG_WRAPPER_KALLSYMS_H */