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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 15struct vm_area_struct; /* vma defining user mapping in mm_types.h */ 16struct 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 55struct 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 66struct 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 */ 90extern void vm_unmap_ram(const void *mem, unsigned int count); 91extern void *vm_map_ram(struct page **pages, unsigned int count, 92 int node, pgprot_t prot); 93extern void vm_unmap_aliases(void); 94 95#ifdef CONFIG_MMU 96extern void __init vmalloc_init(void); 97extern unsigned long vmalloc_nr_pages(void); 98#else 99static inline void vmalloc_init(void) 100{ 101} 102static inline unsigned long vmalloc_nr_pages(void) { return 0; } 103#endif 104 105extern void *vmalloc(unsigned long size); 106extern void *vzalloc(unsigned long size); 107extern void *vmalloc_user(unsigned long size); 108extern void *vmalloc_node(unsigned long size, int node); 109extern void *vzalloc_node(unsigned long size, int node); 110extern void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags); 111extern void *vmalloc_exec(unsigned long size); 112extern void *vmalloc_32(unsigned long size); 113extern void *vmalloc_32_user(unsigned long size); 114extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot); 115extern 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 120extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags); 121static 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 127extern void *__vmalloc_node_flags_caller(unsigned long size, 128 int node, gfp_t flags, void *caller); 129#endif 130 131extern void vfree(const void *addr); 132extern void vfree_atomic(const void *addr); 133 134extern void *vmap(struct page **pages, unsigned int count, 135 unsigned long flags, pgprot_t prot); 136extern void vunmap(const void *addr); 137 138extern int remap_vmalloc_range_partial(struct vm_area_struct *vma, 139 unsigned long uaddr, void *kaddr, 140 unsigned long size); 141 142extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, 143 unsigned long pgoff); 144void vmalloc_sync_all(void); 145 146/* 147 * Lowlevel-APIs (not for driver use!) 148 */ 149 150static inline size_t get_vm_area_size(const struct vm_struct *area) 151{ 152 if (!(area->flags & VM_NO_GUARD)) 153 /* return actual size without guard page */ 154 return area->size - PAGE_SIZE; 155 else 156 return area->size; 157 158} 159 160extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags); 161extern struct vm_struct *get_vm_area_caller(unsigned long size, 162 unsigned long flags, const void *caller); 163extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, 164 unsigned long start, unsigned long end); 165extern struct vm_struct *__get_vm_area_caller(unsigned long size, 166 unsigned long flags, 167 unsigned long start, unsigned long end, 168 const void *caller); 169extern struct vm_struct *remove_vm_area(const void *addr); 170extern struct vm_struct *find_vm_area(const void *addr); 171 172extern int map_vm_area(struct vm_struct *area, pgprot_t prot, 173 struct page **pages); 174#ifdef CONFIG_MMU 175extern int map_kernel_range_noflush(unsigned long start, unsigned long size, 176 pgprot_t prot, struct page **pages); 177extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size); 178extern void unmap_kernel_range(unsigned long addr, unsigned long size); 179static inline void set_vm_flush_reset_perms(void *addr) 180{ 181 struct vm_struct *vm = find_vm_area(addr); 182 183 if (vm) 184 vm->flags |= VM_FLUSH_RESET_PERMS; 185} 186#else 187static inline int 188map_kernel_range_noflush(unsigned long start, unsigned long size, 189 pgprot_t prot, struct page **pages) 190{ 191 return size >> PAGE_SHIFT; 192} 193static inline void 194unmap_kernel_range_noflush(unsigned long addr, unsigned long size) 195{ 196} 197static inline void 198unmap_kernel_range(unsigned long addr, unsigned long size) 199{ 200} 201static inline void set_vm_flush_reset_perms(void *addr) 202{ 203} 204#endif 205 206/* Allocate/destroy a 'vmalloc' VM area. */ 207extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes); 208extern void free_vm_area(struct vm_struct *area); 209 210/* for /dev/kmem */ 211extern long vread(char *buf, char *addr, unsigned long count); 212extern long vwrite(char *buf, char *addr, unsigned long count); 213 214/* 215 * Internals. Dont't use.. 216 */ 217extern struct list_head vmap_area_list; 218extern __init void vm_area_add_early(struct vm_struct *vm); 219extern __init void vm_area_register_early(struct vm_struct *vm, size_t align); 220 221#ifdef CONFIG_SMP 222# ifdef CONFIG_MMU 223struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, 224 const size_t *sizes, int nr_vms, 225 size_t align); 226 227void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms); 228# else 229static inline struct vm_struct ** 230pcpu_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 237static inline void 238pcpu_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 250int register_vmap_purge_notifier(struct notifier_block *nb); 251int unregister_vmap_purge_notifier(struct notifier_block *nb); 252 253#endif /* _LINUX_VMALLOC_H */