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 | ||
| 868e0b6d MJ |
15 | #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,18,0)) |
| 16 | #include <linux/blkdev.h> | |
| 17 | #else | |
| f0dbdefb | 18 | #include <linux/genhd.h> |
| 868e0b6d | 19 | #endif |
| f0dbdefb | 20 | |
| fe72ab45 MJ |
21 | #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,17,0)) |
| 22 | #define LTTNG_GENHD_FL_HIDDEN GENHD_FL_HIDDEN | |
| 23 | #else | |
| 24 | #define LTTNG_GENHD_FL_HIDDEN GENHD_FL_SUPPRESS_PARTITION_INFO | |
| 25 | #endif | |
| 26 | ||
| ff04d185 | 27 | #ifdef CONFIG_KALLSYMS_ALL |
| f0dbdefb HD |
28 | |
| 29 | #include <linux/kallsyms.h> | |
| 5a2f5e92 | 30 | #include <wrapper/kallsyms.h> |
| f0dbdefb | 31 | |
| f0dbdefb HD |
32 | static inline |
| 33 | struct class *wrapper_get_block_class(void) | |
| 34 | { | |
| 35 | struct class *ptr_block_class; | |
| 36 | ||
| 37 | ptr_block_class = (struct class *) kallsyms_lookup_dataptr("block_class"); | |
| 38 | if (!ptr_block_class) { | |
| e36de50d | 39 | printk_once(KERN_WARNING "LTTng: block_class symbol lookup failed.\n"); |
| f0dbdefb HD |
40 | return NULL; |
| 41 | } | |
| 42 | return ptr_block_class; | |
| 43 | } | |
| 44 | ||
| 3dfec228 MJ |
45 | /* |
| 46 | * Canary function to check for 'block_class' at compile time. | |
| 47 | * | |
| 48 | * From 'include/linux/genhd.h': | |
| 49 | * | |
| 50 | * extern struct class block_class; | |
| 51 | */ | |
| 52 | static inline | |
| 53 | struct class *__canary__get_block_class(void) | |
| 54 | { | |
| 55 | return &block_class; | |
| 56 | } | |
| 57 | ||
| f0dbdefb HD |
58 | static inline |
| 59 | struct device_type *wrapper_get_disk_type(void) | |
| 60 | { | |
| 61 | struct device_type *ptr_disk_type; | |
| 62 | ||
| 63 | ptr_disk_type = (struct device_type *) kallsyms_lookup_dataptr("disk_type"); | |
| 64 | if (!ptr_disk_type) { | |
| e36de50d | 65 | printk_once(KERN_WARNING "LTTng: disk_type symbol lookup failed.\n"); |
| f0dbdefb HD |
66 | return NULL; |
| 67 | } | |
| 68 | return ptr_disk_type; | |
| 69 | } | |
| 70 | ||
| 3dfec228 MJ |
71 | /* |
| 72 | * No canary for 'disk_type', it's only defined in 'block/genhd.c'. | |
| 73 | * | |
| 74 | * static inline | |
| 75 | * struct device_type *__canary__get_disk_type(void) | |
| 76 | * { | |
| 77 | * return &disk_type; | |
| 78 | * } | |
| 79 | */ | |
| 80 | ||
| f0dbdefb HD |
81 | #else |
| 82 | ||
| 83 | static inline | |
| 84 | struct class *wrapper_get_block_class(void) | |
| 85 | { | |
| 86 | /* | |
| 87 | * Symbol block_class is not exported. | |
| 88 | * TODO: return &block_class; | |
| 89 | */ | |
| 90 | /* Feature currently unavailable without KALLSYMS_ALL */ | |
| 91 | return NULL; | |
| 92 | } | |
| 93 | ||
| 94 | static inline | |
| 95 | struct device_type *wrapper_get_disk_type(void) | |
| 96 | { | |
| 97 | /* | |
| 98 | * Symbol disk_type is not exported. | |
| 99 | * TODO: return &disk_type; | |
| 100 | */ | |
| 101 | /* Feature currently unavailable without KALLSYMS_ALL */ | |
| 102 | return NULL; | |
| 103 | } | |
| 104 | ||
| 105 | #endif | |
| 106 | ||
| 107 | #endif /* _LTTNG_WRAPPER_GENHD_H */ |