projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| 389d7070 MD |
2 | * wrapper/page_alloc.c |
| 3 | * | |
| 0e14d6e7 MD |
4 | * wrapper around get_pfnblock_flags_mask and Ubuntu |
| 5 | * get_pageblock_flags_mask. Using KALLSYMS to get their address when | |
| 6 | * available, else we need to have a kernel that exports this function | |
| 7 | * to GPL modules. | |
| 389d7070 MD |
8 | * |
| 9 | * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 389d7070 MD |
10 | */ |
| 11 | ||
| 5a90857e | 12 | #ifdef CONFIG_KALLSYMS |
| 389d7070 MD |
13 | |
| 14 | #include <linux/kallsyms.h> | |
| 15 | #include <linux/mm_types.h> | |
| 16 | #include <linux/module.h> | |
| 5a2f5e92 MD |
17 | #include <wrapper/kallsyms.h> |
| 18 | #include <wrapper/page_alloc.h> | |
| 389d7070 MD |
19 | |
| 20 | static | |
| 21 | unsigned long (*get_pfnblock_flags_mask_sym)(struct page *page, | |
| 22 | unsigned long pfn, | |
| 23 | unsigned long end_bitidx, | |
| 24 | unsigned long mask); | |
| 25 | ||
| 26 | unsigned long wrapper_get_pfnblock_flags_mask(struct page *page, | |
| 27 | unsigned long pfn, | |
| 28 | unsigned long end_bitidx, | |
| 29 | unsigned long mask) | |
| 30 | { | |
| 31 | WARN_ON_ONCE(!get_pfnblock_flags_mask_sym); | |
| 32 | if (get_pfnblock_flags_mask_sym) { | |
| 33 | return get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask); | |
| 34 | } else { | |
| 35 | return -ENOSYS; | |
| 36 | } | |
| 37 | } | |
| 38 | EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask); | |
| 39 | ||
| 40 | int wrapper_get_pfnblock_flags_mask_init(void) | |
| 41 | { | |
| 42 | get_pfnblock_flags_mask_sym = | |
| 43 | (void *) kallsyms_lookup_funcptr("get_pfnblock_flags_mask"); | |
| 44 | if (!get_pfnblock_flags_mask_sym) | |
| 45 | return -1; | |
| 46 | return 0; | |
| 47 | } | |
| 1c999280 | 48 | EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init); |
| 389d7070 | 49 | |
| 3dfec228 MJ |
50 | /* |
| 51 | * Canary function to check for 'get_pfnblock_flags_mask()' at compile time. | |
| 52 | * | |
| 53 | * From 'include/linux/pageblock-flags.h': | |
| 54 | * | |
| 55 | * unsigned long get_pfnblock_flags_mask(struct page *page, | |
| 56 | * unsigned long pfn, | |
| 57 | * unsigned long end_bitidx, | |
| 58 | * unsigned long mask); | |
| 59 | */ | |
| 60 | __attribute__((unused)) static | |
| 61 | unsigned long __canary__get_pfnblock_flags_mask(struct page *page, | |
| 62 | unsigned long pfn, | |
| 63 | unsigned long end_bitidx, | |
| 64 | unsigned long mask) | |
| 65 | { | |
| 66 | return get_pfnblock_flags_mask(page, pfn, end_bitidx, mask); | |
| 67 | } | |
| 68 | ||
| 0e14d6e7 | 69 | #else |
| 389d7070 MD |
70 | |
| 71 | #include <linux/pageblock-flags.h> | |
| 72 | ||
| 0e14d6e7 | 73 | #endif |