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, int node); 92 extern void vm_unmap_aliases(void); 93 94 #ifdef CONFIG_MMU 95 extern void __init vmalloc_init(void); 96 extern unsigned long vmalloc_nr_pages(void); 97 #else 98 static inline void vmalloc_init(void) 99 { 100 } 101 static inline unsigned long vmalloc_nr_pages(void) { return 0; } 102 #endif 103 104 extern void *vmalloc(unsigned long size); 105 extern void *vzalloc(unsigned long size); 106 extern void *vmalloc_user(unsigned long size); 107 extern void *vmalloc_node(unsigned long size, int node); 108 extern void *vzalloc_node(unsigned long size, int node); 109 extern void *vmalloc_exec(unsigned long size); 110 extern void *vmalloc_32(unsigned long size); 111 extern void *vmalloc_32_user(unsigned long size); 112 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask); 113 extern void *__vmalloc_node_range(unsigned long size, unsigned long align, 114 unsigned long start, unsigned long end, gfp_t gfp_mask, 115 pgprot_t prot, unsigned long vm_flags, int node, 116 const void *caller); 117 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, 118 int node, const void *caller); 119 120 extern void vfree(const void *addr); 121 extern void vfree_atomic(const void *addr); 122 123 extern void *vmap(struct page **pages, unsigned int count, 124 unsigned long flags, pgprot_t prot); 125 extern void vunmap(const void *addr); 126 127 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma, 128 unsigned long uaddr, void *kaddr, 129 unsigned long pgoff, unsigned long size); 130 131 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, 132 unsigned long pgoff); 133 134 /* 135 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values 136 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings() 137 * needs to be called. 138 */ 139 #ifndef ARCH_PAGE_TABLE_SYNC_MASK 140 #define ARCH_PAGE_TABLE_SYNC_MASK 0 141 #endif 142 143 /* 144 * There is no default implementation for arch_sync_kernel_mappings(). It is 145 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK 146 * is 0. 147 */ 148 void arch_sync_kernel_mappings(unsigned long start, unsigned long end); 149 150 /* 151 * Lowlevel-APIs (not for driver use!) 152 */ 153 154 static inline size_t get_vm_area_size(const struct vm_struct *area) 155 { 156 if (!(area->flags & VM_NO_GUARD)) 157 /* return actual size without guard page */ 158 return area->size - PAGE_SIZE; 159 else 160 return area->size; 161 162 } 163 164 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags); 165 extern struct vm_struct *get_vm_area_caller(unsigned long size, 166 unsigned long flags, const void *caller); 167 extern struct vm_struct *__get_vm_area_caller(unsigned long size, 168 unsigned long flags, 169 unsigned long start, unsigned long end, 170 const void *caller); 171 extern struct vm_struct *remove_vm_area(const void *addr); 172 extern struct vm_struct *find_vm_area(const void *addr); 173 174 #ifdef CONFIG_MMU 175 extern int map_kernel_range_noflush(unsigned long start, unsigned long size, 176 pgprot_t prot, struct page **pages); 177 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot, 178 struct page **pages); 179 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size); 180 extern void unmap_kernel_range(unsigned long addr, unsigned long size); 181 static inline void set_vm_flush_reset_perms(void *addr) 182 { 183 struct vm_struct *vm = find_vm_area(addr); 184 185 if (vm) 186 vm->flags |= VM_FLUSH_RESET_PERMS; 187 } 188 #else 189 static inline int 190 map_kernel_range_noflush(unsigned long start, unsigned long size, 191 pgprot_t prot, struct page **pages) 192 { 193 return size >> PAGE_SHIFT; 194 } 195 #define map_kernel_range map_kernel_range_noflush 196 static inline void 197 unmap_kernel_range_noflush(unsigned long addr, unsigned long size) 198 { 199 } 200 #define unmap_kernel_range unmap_kernel_range_noflush 201 static inline void set_vm_flush_reset_perms(void *addr) 202 { 203 } 204 #endif 205 206 /* Allocate/destroy a 'vmalloc' VM area. */ 207 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes); 208 extern void free_vm_area(struct vm_struct *area); 209 210 /* for /dev/kmem */ 211 extern long vread(char *buf, char *addr, unsigned long count); 212 extern long vwrite(char *buf, char *addr, unsigned long count); 213 214 /* 215 * Internals. Dont't use.. 216 */ 217 extern struct list_head vmap_area_list; 218 extern __init void vm_area_add_early(struct vm_struct *vm); 219 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align); 220 221 #ifdef CONFIG_SMP 222 # ifdef CONFIG_MMU 223 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, 224 const size_t *sizes, int nr_vms, 225 size_t align); 226 227 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms); 228 # else 229 static inline struct vm_struct ** 230 pcpu_get_vm_areas(const unsigned long *offsets, 231 const size_t *sizes, int nr_vms, 232 size_t align) 233 { 234 return NULL; 235 } 236 237 static inline void 238 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) 239 { 240 } 241 # endif 242 #endif 243 244 #ifdef CONFIG_MMU 245 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START) 246 #else 247 #define VMALLOC_TOTAL 0UL 248 #endif 249 250 int register_vmap_purge_notifier(struct notifier_block *nb); 251 int unregister_vmap_purge_notifier(struct notifier_block *nb); 252 253 #endif /* _LINUX_VMALLOC_H */ 254