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_32(unsigned long size); 110 extern void *vmalloc_32_user(unsigned long size); 111 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask); 112 extern void *__vmalloc_node_range(unsigned long size, unsigned long align, 113 unsigned long start, unsigned long end, gfp_t gfp_mask, 114 pgprot_t prot, unsigned long vm_flags, int node, 115 const void *caller); 116 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, 117 int node, const void *caller); 118 119 extern void vfree(const void *addr); 120 extern void vfree_atomic(const void *addr); 121 122 extern void *vmap(struct page **pages, unsigned int count, 123 unsigned long flags, pgprot_t prot); 124 extern void vunmap(const void *addr); 125 126 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma, 127 unsigned long uaddr, void *kaddr, 128 unsigned long pgoff, unsigned long size); 129 130 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, 131 unsigned long pgoff); 132 133 /* 134 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values 135 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings() 136 * needs to be called. 137 */ 138 #ifndef ARCH_PAGE_TABLE_SYNC_MASK 139 #define ARCH_PAGE_TABLE_SYNC_MASK 0 140 #endif 141 142 /* 143 * There is no default implementation for arch_sync_kernel_mappings(). It is 144 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK 145 * is 0. 146 */ 147 void arch_sync_kernel_mappings(unsigned long start, unsigned long end); 148 149 /* 150 * Lowlevel-APIs (not for driver use!) 151 */ 152 153 static inline size_t get_vm_area_size(const struct vm_struct *area) 154 { 155 if (!(area->flags & VM_NO_GUARD)) 156 /* return actual size without guard page */ 157 return area->size - PAGE_SIZE; 158 else 159 return area->size; 160 161 } 162 163 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags); 164 extern struct vm_struct *get_vm_area_caller(unsigned long size, 165 unsigned long flags, const void *caller); 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 #ifdef CONFIG_MMU 174 extern int map_kernel_range_noflush(unsigned long start, unsigned long size, 175 pgprot_t prot, struct page **pages); 176 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot, 177 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 #define map_kernel_range map_kernel_range_noflush 195 static inline void 196 unmap_kernel_range_noflush(unsigned long addr, unsigned long size) 197 { 198 } 199 #define unmap_kernel_range unmap_kernel_range_noflush 200 static inline void set_vm_flush_reset_perms(void *addr) 201 { 202 } 203 #endif 204 205 /* Allocate/destroy a 'vmalloc' VM area. */ 206 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes); 207 extern void free_vm_area(struct vm_struct *area); 208 209 /* for /dev/kmem */ 210 extern long vread(char *buf, char *addr, unsigned long count); 211 extern long vwrite(char *buf, char *addr, unsigned long count); 212 213 /* 214 * Internals. Dont't use.. 215 */ 216 extern struct list_head vmap_area_list; 217 extern __init void vm_area_add_early(struct vm_struct *vm); 218 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align); 219 220 #ifdef CONFIG_SMP 221 # ifdef CONFIG_MMU 222 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, 223 const size_t *sizes, int nr_vms, 224 size_t align); 225 226 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms); 227 # else 228 static inline struct vm_struct ** 229 pcpu_get_vm_areas(const unsigned long *offsets, 230 const size_t *sizes, int nr_vms, 231 size_t align) 232 { 233 return NULL; 234 } 235 236 static inline void 237 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) 238 { 239 } 240 # endif 241 #endif 242 243 #ifdef CONFIG_MMU 244 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START) 245 #else 246 #define VMALLOC_TOTAL 0UL 247 #endif 248 249 int register_vmap_purge_notifier(struct notifier_block *nb); 250 int unregister_vmap_purge_notifier(struct notifier_block *nb); 251 252 #endif /* _LINUX_VMALLOC_H */ 253