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