| 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| 2 | * wrapper/page_alloc.c |
| 3 | * |
| 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. |
| 8 | * |
| 9 | * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 10 | */ |
| 11 | |
| 12 | #ifdef CONFIG_KALLSYMS |
| 13 | |
| 14 | /* Include page_alloc wrapper before pageblock-flags.h. */ |
| 15 | #include <wrapper/page_alloc.h> |
| 16 | |
| 17 | #include <linux/pageblock-flags.h> |
| 18 | #include <linux/kallsyms.h> |
| 19 | #include <linux/mm_types.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <wrapper/kallsyms.h> |
| 22 | #include <lttng/kernel-version.h> |
| 23 | |
| 24 | #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,14,0)) |
| 25 | static |
| 26 | unsigned long (*get_pfnblock_flags_mask_sym)(const struct page *page, |
| 27 | unsigned long pfn, |
| 28 | unsigned long mask); |
| 29 | |
| 30 | unsigned long wrapper_get_pfnblock_flags_mask(const struct page *page, |
| 31 | unsigned long pfn, |
| 32 | unsigned long mask) |
| 33 | { |
| 34 | WARN_ON_ONCE(!get_pfnblock_flags_mask_sym); |
| 35 | if (get_pfnblock_flags_mask_sym) { |
| 36 | struct irq_ibt_state irq_ibt_state; |
| 37 | unsigned long ret; |
| 38 | |
| 39 | irq_ibt_state = wrapper_irq_ibt_save(); |
| 40 | ret = get_pfnblock_flags_mask_sym(page, pfn, mask); |
| 41 | wrapper_irq_ibt_restore(irq_ibt_state); |
| 42 | return ret; |
| 43 | } else { |
| 44 | return -ENOSYS; |
| 45 | } |
| 46 | } |
| 47 | #elif (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,9,0)) |
| 48 | static |
| 49 | unsigned long (*get_pfnblock_flags_mask_sym)(struct page *page, |
| 50 | unsigned long pfn, |
| 51 | unsigned long mask); |
| 52 | |
| 53 | unsigned long wrapper_get_pfnblock_flags_mask(struct page *page, |
| 54 | unsigned long pfn, |
| 55 | unsigned long mask) |
| 56 | { |
| 57 | WARN_ON_ONCE(!get_pfnblock_flags_mask_sym); |
| 58 | if (get_pfnblock_flags_mask_sym) { |
| 59 | struct irq_ibt_state irq_ibt_state; |
| 60 | unsigned long ret; |
| 61 | |
| 62 | irq_ibt_state = wrapper_irq_ibt_save(); |
| 63 | ret = get_pfnblock_flags_mask_sym(page, pfn, mask); |
| 64 | wrapper_irq_ibt_restore(irq_ibt_state); |
| 65 | return ret; |
| 66 | } else { |
| 67 | return -ENOSYS; |
| 68 | } |
| 69 | } |
| 70 | #else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,9,0)) */ |
| 71 | static |
| 72 | unsigned long (*get_pfnblock_flags_mask_sym)(struct page *page, |
| 73 | unsigned long pfn, |
| 74 | unsigned long end_bitidx, |
| 75 | unsigned long mask); |
| 76 | |
| 77 | unsigned long wrapper_get_pfnblock_flags_mask(struct page *page, |
| 78 | unsigned long pfn, |
| 79 | unsigned long end_bitidx, |
| 80 | unsigned long mask) |
| 81 | { |
| 82 | WARN_ON_ONCE(!get_pfnblock_flags_mask_sym); |
| 83 | if (get_pfnblock_flags_mask_sym) { |
| 84 | struct irq_ibt_state irq_ibt_state; |
| 85 | unsigned long ret; |
| 86 | |
| 87 | irq_ibt_state = wrapper_irq_ibt_save(); |
| 88 | ret = get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask); |
| 89 | wrapper_irq_ibt_restore(irq_ibt_state); |
| 90 | return ret; |
| 91 | } else { |
| 92 | return -ENOSYS; |
| 93 | } |
| 94 | } |
| 95 | #endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,9,0)) */ |
| 96 | |
| 97 | EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask); |
| 98 | |
| 99 | int wrapper_get_pfnblock_flags_mask_init(void) |
| 100 | { |
| 101 | get_pfnblock_flags_mask_sym = |
| 102 | (void *) kallsyms_lookup_funcptr("get_pfnblock_flags_mask"); |
| 103 | if (!get_pfnblock_flags_mask_sym) |
| 104 | return -1; |
| 105 | return 0; |
| 106 | } |
| 107 | EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init); |
| 108 | |
| 109 | #else |
| 110 | |
| 111 | #include <linux/pageblock-flags.h> |
| 112 | |
| 113 | #endif |