1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_VMALLOC_H 3 #define _LINUX_VMALLOC_H 4 5 #include <linux/spinlock.h> 6 #include <linux/init.h> 7 #include <linux/list.h> 8 #include <linux/llist.h> 9 #include <asm/page.h> /* pgprot_t */ 10 #include <linux/rbtree.h> 11 #include <linux/overflow.h> 12 13 #include <asm/vmalloc.h> 14 15 struct vm_area_struct; /* vma defining user mapping in mm_types.h */ 16 struct notifier_block; /* in notifier.h */ 17 18 /* bits in flags of vmalloc's vm_struct below */ 19 #define VM_IOREMAP 0x00000001 /* ioremap() and friends */ 20 #define VM_ALLOC 0x00000002 /* vmalloc() */ 21 #define VM_MAP 0x00000004 /* vmap()ed pages */ 22 #define VM_USERMAP 0x00000008 /* suitable for remap_vmalloc_range */ 23 #define VM_DMA_COHERENT 0x00000010 /* dma_alloc_coherent */ 24 #define VM_UNINITIALIZED 0x00000020 /* vm_struct is not fully initialized */ 25 #define VM_NO_GUARD 0x00000040 /* don't add guard page */ 26 #define VM_KASAN 0x00000080 /* has allocated kasan shadow memory */ 27 28 /* 29 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC. 30 * 31 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after 32 * shadow memory has been mapped. It's used to handle allocation errors so that 33 * we don't try to poision shadow on free if it was never allocated. 34 * 35 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to 36 * determine which allocations need the module shadow freed. 37 */ 38 39 /* 40 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with 41 * vfree_atomic(). 42 */ 43 #define VM_FLUSH_RESET_PERMS 0x00000100 /* Reset direct map and flush TLB on unmap */ 44 45 /* bits [20..32] reserved for arch specific ioremap internals */ 46 47 /* 48 * Maximum alignment for ioremap() regions. 49 * Can be overriden by arch-specific value. 50 */ 51 #ifndef IOREMAP_MAX_ORDER 52 #define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */ 53 #endif 54 55 struct vm_struct { 56 struct vm_struct *next; 57 void *addr; 58 unsigned long size; 59 unsigned long flags; 60 struct page **pages; 61 unsigned int nr_pages; 62 phys_addr_t phys_addr; 63 const void *caller; 64 }; 65 66 struct vmap_area { 67 unsigned long va_start; 68 unsigned long va_end; 69 70 struct rb_node rb_node; /* address sorted rbtree */ 71 struct list_head list; /* address sorted list */ 72 73 /* 74 * The following three variables can be packed, because 75 * a vmap_area object is always one of the three states: 76 * 1) in "free" tree (root is vmap_area_root) 77 * 2) in "busy" tree (root is free_vmap_area_root) 78 * 3) in purge list (head is vmap_purge_list) 79 */ 80 union { 81 unsigned long subtree_max_size; /* in "free" tree */ 82 struct vm_struct *vm; /* in "busy" tree */ 83 struct llist_node purge_list; /* in purge list */ 84 }; 85 }; 86 87 /* 88 * Highlevel APIs for driver use 89 */ 90 extern void vm_unmap_ram(const void *mem, unsigned int count); 91 extern void *vm_map_ram(struct page **pages, unsigned int count, 92 int node, pgprot_t prot); 93 extern void vm_unmap_aliases(void); 94 95 #ifdef CONFIG_MMU 96 extern void __init vmalloc_init(void); 97 extern unsigned long vmalloc_nr_pages(void); 98 #else 99 static inline void vmalloc_init(void) 100 { 101 } 102 static inline unsigned long vmalloc_nr_pages(void) { return 0; } 103 #endif 104 105 extern void *vmalloc(unsigned long size); 106 extern void *vzalloc(unsigned long size); 107 extern void *vmalloc_user(unsigned long size); 108 extern void *vmalloc_node(unsigned long size, int node); 109 extern void *vzalloc_node(unsigned long size, int node); 110 extern void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags); 111 extern void *vmalloc_exec(unsigned long size); 112 extern void *vmalloc_32(unsigned long size); 113 extern void *vmalloc_32_user(unsigned long size); 114 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot); 115 extern void *__vmalloc_node_range(unsigned long size, unsigned long align, 116 unsigned long start, unsigned long end, gfp_t gfp_mask, 117 pgprot_t prot, unsigned long vm_flags, int node, 118 const void *caller); 119 #ifndef CONFIG_MMU 120 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags); 121 static inline void *__vmalloc_node_flags_caller(unsigned long size, int node, 122 gfp_t flags, void *caller) 123 { 124 return __vmalloc_node_flags(size, node, flags); 125 } 126 #else 127 extern void *__vmalloc_node_flags_caller(unsigned long size, 128 int node, gfp_t flags, void *caller); 129 #endif 130 131 extern void vfree(const void *addr); 132 extern void vfree_atomic(const void *addr); 133 134 extern void *vmap(struct page **pages, unsigned int count, 135 unsigned long flags, pgprot_t prot); 136 extern void vunmap(const void *addr); 137 138 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma, 139 unsigned long uaddr, void *kaddr, 140 unsigned long pgoff, unsigned long size); 141 142 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, 143 unsigned long pgoff); 144 void vmalloc_sync_mappings(void); 145 void vmalloc_sync_unmappings(void); 146 147 /* 148 * Lowlevel-APIs (not for driver use!) 149 */ 150 151 static inline size_t get_vm_area_size(const struct vm_struct *area) 152 { 153 if (!(area->flags & VM_NO_GUARD)) 154 /* return actual size without guard page */ 155 return area->size - PAGE_SIZE; 156 else 157 return area->size; 158 159 } 160 161 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags); 162 extern struct vm_struct *get_vm_area_caller(unsigned long size, 163 unsigned long flags, const void *caller); 164 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, 165 unsigned long start, unsigned long end); 166 extern struct vm_struct *__get_vm_area_caller(unsigned long size, 167 unsigned long flags, 168 unsigned long start, unsigned long end, 169 const void *caller); 170 extern struct vm_struct *remove_vm_area(const void *addr); 171 extern struct vm_struct *find_vm_area(const void *addr); 172 173 extern int map_vm_area(struct vm_struct *area, pgprot_t prot, 174 struct page **pages); 175 #ifdef CONFIG_MMU 176 extern int map_kernel_range_noflush(unsigned long start, unsigned long size, 177 pgprot_t prot, struct page **pages); 178 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size); 179 extern void unmap_kernel_range(unsigned long addr, unsigned long size); 180 static inline void set_vm_flush_reset_perms(void *addr) 181 { 182 struct vm_struct *vm = find_vm_area(addr); 183 184 if (vm) 185 vm->flags |= VM_FLUSH_RESET_PERMS; 186 } 187 #else 188 static inline int 189 map_kernel_range_noflush(unsigned long start, unsigned long size, 190 pgprot_t prot, struct page **pages) 191 { 192 return size >> PAGE_SHIFT; 193 } 194 static inline void 195 unmap_kernel_range_noflush(unsigned long addr, unsigned long size) 196 { 197 } 198 static inline void 199 unmap_kernel_range(unsigned long addr, unsigned long size) 200 { 201 } 202 static inline void set_vm_flush_reset_perms(void *addr) 203 { 204 } 205 #endif 206 207 /* Allocate/destroy a 'vmalloc' VM area. */ 208 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes); 209 extern void free_vm_area(struct vm_struct *area); 210 211 /* for /dev/kmem */ 212 extern long vread(char *buf, char *addr, unsigned long count); 213 extern long vwrite(char *buf, char *addr, unsigned long count); 214 215 /* 216 * Internals. Dont't use.. 217 */ 218 extern struct list_head vmap_area_list; 219 extern __init void vm_area_add_early(struct vm_struct *vm); 220 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align); 221 222 #ifdef CONFIG_SMP 223 # ifdef CONFIG_MMU 224 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, 225 const size_t *sizes, int nr_vms, 226 size_t align); 227 228 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms); 229 # else 230 static inline struct vm_struct ** 231 pcpu_get_vm_areas(const unsigned long *offsets, 232 const size_t *sizes, int nr_vms, 233 size_t align) 234 { 235 return NULL; 236 } 237 238 static inline void 239 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) 240 { 241 } 242 # endif 243 #endif 244 245 #ifdef CONFIG_MMU 246 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START) 247 #else 248 #define VMALLOC_TOTAL 0UL 249 #endif 250 251 int register_vmap_purge_notifier(struct notifier_block *nb); 252 int unregister_vmap_purge_notifier(struct notifier_block *nb); 253 254 #endif /* _LINUX_VMALLOC_H */ 255