| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | /* |
| 3 | * KMSAN API for subsystems. |
| 4 | * |
| 5 | * Copyright (C) 2017-2022 Google LLC |
| 6 | * Author: Alexander Potapenko <glider@google.com> |
| 7 | * |
| 8 | */ |
| 9 | #ifndef _LINUX_KMSAN_H |
| 10 | #define _LINUX_KMSAN_H |
| 11 | |
| 12 | #include <linux/gfp.h> |
| 13 | #include <linux/kmsan-checks.h> |
| 14 | #include <linux/types.h> |
| 15 | |
| 16 | struct page; |
| 17 | struct kmem_cache; |
| 18 | |
| 19 | #ifdef CONFIG_KMSAN |
| 20 | |
| 21 | /** |
| 22 | * kmsan_alloc_page() - Notify KMSAN about an alloc_pages() call. |
| 23 | * @page: struct page pointer returned by alloc_pages(). |
| 24 | * @order: order of allocated struct page. |
| 25 | * @flags: GFP flags used by alloc_pages() |
| 26 | * |
| 27 | * KMSAN marks 1<<@order pages starting at @page as uninitialized, unless |
| 28 | * @flags contain __GFP_ZERO. |
| 29 | */ |
| 30 | void kmsan_alloc_page(struct page *page, unsigned int order, gfp_t flags); |
| 31 | |
| 32 | /** |
| 33 | * kmsan_free_page() - Notify KMSAN about a free_pages() call. |
| 34 | * @page: struct page pointer passed to free_pages(). |
| 35 | * @order: order of deallocated struct page. |
| 36 | * |
| 37 | * KMSAN marks freed memory as uninitialized. |
| 38 | */ |
| 39 | void kmsan_free_page(struct page *page, unsigned int order); |
| 40 | |
| 41 | /** |
| 42 | * kmsan_copy_page_meta() - Copy KMSAN metadata between two pages. |
| 43 | * @dst: destination page. |
| 44 | * @src: source page. |
| 45 | * |
| 46 | * KMSAN copies the contents of metadata pages for @src into the metadata pages |
| 47 | * for @dst. If @dst has no associated metadata pages, nothing happens. |
| 48 | * If @src has no associated metadata pages, @dst metadata pages are unpoisoned. |
| 49 | */ |
| 50 | void kmsan_copy_page_meta(struct page *dst, struct page *src); |
| 51 | |
| 52 | /** |
| 53 | * kmsan_slab_alloc() - Notify KMSAN about a slab allocation. |
| 54 | * @s: slab cache the object belongs to. |
| 55 | * @object: object pointer. |
| 56 | * @flags: GFP flags passed to the allocator. |
| 57 | * |
| 58 | * Depending on cache flags and GFP flags, KMSAN sets up the metadata of the |
| 59 | * newly created object, marking it as initialized or uninitialized. |
| 60 | */ |
| 61 | void kmsan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags); |
| 62 | |
| 63 | /** |
| 64 | * kmsan_slab_free() - Notify KMSAN about a slab deallocation. |
| 65 | * @s: slab cache the object belongs to. |
| 66 | * @object: object pointer. |
| 67 | * |
| 68 | * KMSAN marks the freed object as uninitialized. |
| 69 | */ |
| 70 | void kmsan_slab_free(struct kmem_cache *s, void *object); |
| 71 | |
| 72 | /** |
| 73 | * kmsan_kmalloc_large() - Notify KMSAN about a large slab allocation. |
| 74 | * @ptr: object pointer. |
| 75 | * @size: object size. |
| 76 | * @flags: GFP flags passed to the allocator. |
| 77 | * |
| 78 | * Similar to kmsan_slab_alloc(), but for large allocations. |
| 79 | */ |
| 80 | void kmsan_kmalloc_large(const void *ptr, size_t size, gfp_t flags); |
| 81 | |
| 82 | /** |
| 83 | * kmsan_kfree_large() - Notify KMSAN about a large slab deallocation. |
| 84 | * @ptr: object pointer. |
| 85 | * |
| 86 | * Similar to kmsan_slab_free(), but for large allocations. |
| 87 | */ |
| 88 | void kmsan_kfree_large(const void *ptr); |
| 89 | |
| 90 | /** |
| 91 | * kmsan_map_kernel_range_noflush() - Notify KMSAN about a vmap. |
| 92 | * @start: start of vmapped range. |
| 93 | * @end: end of vmapped range. |
| 94 | * @prot: page protection flags used for vmap. |
| 95 | * @pages: array of pages. |
| 96 | * @page_shift: page_shift passed to vmap_range_noflush(). |
| 97 | * |
| 98 | * KMSAN maps shadow and origin pages of @pages into contiguous ranges in |
| 99 | * vmalloc metadata address range. |
| 100 | */ |
| 101 | void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, |
| 102 | pgprot_t prot, struct page **pages, |
| 103 | unsigned int page_shift); |
| 104 | |
| 105 | /** |
| 106 | * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap. |
| 107 | * @start: start of vunmapped range. |
| 108 | * @end: end of vunmapped range. |
| 109 | * |
| 110 | * KMSAN unmaps the contiguous metadata ranges created by |
| 111 | * kmsan_map_kernel_range_noflush(). |
| 112 | */ |
| 113 | void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end); |
| 114 | |
| 115 | /** |
| 116 | * kmsan_ioremap_page_range() - Notify KMSAN about a ioremap_page_range() call. |
| 117 | * @addr: range start. |
| 118 | * @end: range end. |
| 119 | * @phys_addr: physical range start. |
| 120 | * @prot: page protection flags used for ioremap_page_range(). |
| 121 | * @page_shift: page_shift argument passed to vmap_range_noflush(). |
| 122 | * |
| 123 | * KMSAN creates new metadata pages for the physical pages mapped into the |
| 124 | * virtual memory. |
| 125 | */ |
| 126 | void kmsan_ioremap_page_range(unsigned long addr, unsigned long end, |
| 127 | phys_addr_t phys_addr, pgprot_t prot, |
| 128 | unsigned int page_shift); |
| 129 | |
| 130 | /** |
| 131 | * kmsan_iounmap_page_range() - Notify KMSAN about a iounmap_page_range() call. |
| 132 | * @start: range start. |
| 133 | * @end: range end. |
| 134 | * |
| 135 | * KMSAN unmaps the metadata pages for the given range and, unlike for |
| 136 | * vunmap_page_range(), also deallocates them. |
| 137 | */ |
| 138 | void kmsan_iounmap_page_range(unsigned long start, unsigned long end); |
| 139 | |
| 140 | #else |
| 141 | |
| 142 | static inline int kmsan_alloc_page(struct page *page, unsigned int order, |
| 143 | gfp_t flags) |
| 144 | { |
| 145 | return 0; |
| 146 | } |
| 147 | |
| 148 | static inline void kmsan_free_page(struct page *page, unsigned int order) |
| 149 | { |
| 150 | } |
| 151 | |
| 152 | static inline void kmsan_copy_page_meta(struct page *dst, struct page *src) |
| 153 | { |
| 154 | } |
| 155 | |
| 156 | static inline void kmsan_slab_alloc(struct kmem_cache *s, void *object, |
| 157 | gfp_t flags) |
| 158 | { |
| 159 | } |
| 160 | |
| 161 | static inline void kmsan_slab_free(struct kmem_cache *s, void *object) |
| 162 | { |
| 163 | } |
| 164 | |
| 165 | static inline void kmsan_kmalloc_large(const void *ptr, size_t size, |
| 166 | gfp_t flags) |
| 167 | { |
| 168 | } |
| 169 | |
| 170 | static inline void kmsan_kfree_large(const void *ptr) |
| 171 | { |
| 172 | } |
| 173 | |
| 174 | static inline void kmsan_vmap_pages_range_noflush(unsigned long start, |
| 175 | unsigned long end, |
| 176 | pgprot_t prot, |
| 177 | struct page **pages, |
| 178 | unsigned int page_shift) |
| 179 | { |
| 180 | } |
| 181 | |
| 182 | static inline void kmsan_vunmap_range_noflush(unsigned long start, |
| 183 | unsigned long end) |
| 184 | { |
| 185 | } |
| 186 | |
| 187 | static inline void kmsan_ioremap_page_range(unsigned long start, |
| 188 | unsigned long end, |
| 189 | phys_addr_t phys_addr, |
| 190 | pgprot_t prot, |
| 191 | unsigned int page_shift) |
| 192 | { |
| 193 | } |
| 194 | |
| 195 | static inline void kmsan_iounmap_page_range(unsigned long start, |
| 196 | unsigned long end) |
| 197 | { |
| 198 | } |
| 199 | |
| 200 | #endif |
| 201 | |
| 202 | #endif /* _LINUX_KMSAN_H */ |