projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| 9f36eaed | 2 | * |
| f0dbdefb HD |
3 | * wrapper/genhd.h |
| 4 | * | |
| 5 | * wrapper around block layer functions and data structures. Using | |
| 6 | * KALLSYMS to get its address when available, else we need to have a | |
| 7 | * kernel that exports this function to GPL modules. | |
| 8 | * | |
| 9 | * Copyright (C) 2011-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| f0dbdefb HD |
10 | */ |
| 11 | ||
| 9f36eaed MJ |
12 | #ifndef _LTTNG_WRAPPER_GENHD_H |
| 13 | #define _LTTNG_WRAPPER_GENHD_H | |
| 14 | ||
| f0dbdefb HD |
15 | #include <linux/genhd.h> |
| 16 | ||
| fe72ab45 MJ |
17 | #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,17,0)) |
| 18 | #define LTTNG_GENHD_FL_HIDDEN GENHD_FL_HIDDEN | |
| 19 | #else | |
| 20 | #define LTTNG_GENHD_FL_HIDDEN GENHD_FL_SUPPRESS_PARTITION_INFO | |
| 21 | #endif | |
| 22 | ||
| ff04d185 | 23 | #ifdef CONFIG_KALLSYMS_ALL |
| f0dbdefb HD |
24 | |
| 25 | #include <linux/kallsyms.h> | |
| 5a2f5e92 | 26 | #include <wrapper/kallsyms.h> |
| f0dbdefb | 27 | |
| f0dbdefb HD |
28 | static inline |
| 29 | struct class *wrapper_get_block_class(void) | |
| 30 | { | |
| 31 | struct class *ptr_block_class; | |
| 32 | ||
| 33 | ptr_block_class = (struct class *) kallsyms_lookup_dataptr("block_class"); | |
| 34 | if (!ptr_block_class) { | |
| e36de50d | 35 | printk_once(KERN_WARNING "LTTng: block_class symbol lookup failed.\n"); |
| f0dbdefb HD |
36 | return NULL; |
| 37 | } | |
| 38 | return ptr_block_class; | |
| 39 | } | |
| 40 | ||
| 3dfec228 MJ |
41 | /* |
| 42 | * Canary function to check for 'block_class' at compile time. | |
| 43 | * | |
| 44 | * From 'include/linux/genhd.h': | |
| 45 | * | |
| 46 | * extern struct class block_class; | |
| 47 | */ | |
| 48 | static inline | |
| 49 | struct class *__canary__get_block_class(void) | |
| 50 | { | |
| 51 | return &block_class; | |
| 52 | } | |
| 53 | ||
| f0dbdefb HD |
54 | static inline |
| 55 | struct device_type *wrapper_get_disk_type(void) | |
| 56 | { | |
| 57 | struct device_type *ptr_disk_type; | |
| 58 | ||
| 59 | ptr_disk_type = (struct device_type *) kallsyms_lookup_dataptr("disk_type"); | |
| 60 | if (!ptr_disk_type) { | |
| e36de50d | 61 | printk_once(KERN_WARNING "LTTng: disk_type symbol lookup failed.\n"); |
| f0dbdefb HD |
62 | return NULL; |
| 63 | } | |
| 64 | return ptr_disk_type; | |
| 65 | } | |
| 66 | ||
| 3dfec228 MJ |
67 | /* |
| 68 | * No canary for 'disk_type', it's only defined in 'block/genhd.c'. | |
| 69 | * | |
| 70 | * static inline | |
| 71 | * struct device_type *__canary__get_disk_type(void) | |
| 72 | * { | |
| 73 | * return &disk_type; | |
| 74 | * } | |
| 75 | */ | |
| 76 | ||
| f0dbdefb HD |
77 | #else |
| 78 | ||
| 79 | static inline | |
| 80 | struct class *wrapper_get_block_class(void) | |
| 81 | { | |
| 82 | /* | |
| 83 | * Symbol block_class is not exported. | |
| 84 | * TODO: return &block_class; | |
| 85 | */ | |
| 86 | /* Feature currently unavailable without KALLSYMS_ALL */ | |
| 87 | return NULL; | |
| 88 | } | |
| 89 | ||
| 90 | static inline | |
| 91 | struct device_type *wrapper_get_disk_type(void) | |
| 92 | { | |
| 93 | /* | |
| 94 | * Symbol disk_type is not exported. | |
| 95 | * TODO: return &disk_type; | |
| 96 | */ | |
| 97 | /* Feature currently unavailable without KALLSYMS_ALL */ | |
| 98 | return NULL; | |
| 99 | } | |
| 100 | ||
| 101 | #endif | |
| 102 | ||
| 103 | #endif /* _LTTNG_WRAPPER_GENHD_H */ |