include/linux/vmalloc.h

   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 struct vm_area_struct;          /* vma defining user mapping in mm_types.h */
  14 struct notifier_block;          /* in notifier.h */
  15
  16 /* bits in flags of vmalloc's vm_struct below */
  17 #define VM_IOREMAP              0x00000001      /* ioremap() and friends */
  18 #define VM_ALLOC                0x00000002      /* vmalloc() */
  19 #define VM_MAP                  0x00000004      /* vmap()ed pages */
  20 #define VM_USERMAP              0x00000008      /* suitable for remap_vmalloc_range */
  21 #define VM_UNINITIALIZED        0x00000020      /* vm_struct is not fully initialized */
  22 #define VM_NO_GUARD             0x00000040      /* don't add guard page */
  23 #define VM_KASAN                0x00000080      /* has allocated kasan shadow memory */
  24 /* bits [20..32] reserved for arch specific ioremap internals */
  25
  26 /*
  27  * Maximum alignment for ioremap() regions.
  28  * Can be overriden by arch-specific value.
  29  */
  30 #ifndef IOREMAP_MAX_ORDER
  31 #define IOREMAP_MAX_ORDER       (7 + PAGE_SHIFT)        /* 128 pages */
  32 #endif
  33
  34 struct vm_struct {
  35         struct vm_struct        *next;
  36         void                    *addr;
  37         unsigned long           size;
  38         unsigned long           flags;
  39         struct page             **pages;
  40         unsigned int            nr_pages;
  41         phys_addr_t             phys_addr;
  42         const void              *caller;
  43 };
  44
  45 struct vmap_area {
  46         unsigned long va_start;
  47         unsigned long va_end;
  48         unsigned long flags;
  49         struct rb_node rb_node;         /* address sorted rbtree */
  50         struct list_head list;          /* address sorted list */
  51         struct llist_node purge_list;    /* "lazy purge" list */
  52         struct vm_struct *vm;
  53         struct rcu_head rcu_head;
  54 };
  55
  56 /*
  57  *      Highlevel APIs for driver use
  58  */
  59 extern void vm_unmap_ram(const void *mem, unsigned int count);
  60 extern void *vm_map_ram(struct page **pages, unsigned int count,
  61                                 int node, pgprot_t prot);
  62 extern void vm_unmap_aliases(void);
  63
  64 #ifdef CONFIG_MMU
  65 extern void __init vmalloc_init(void);
  66 #else
  67 static inline void vmalloc_init(void)
  68 {
  69 }
  70 #endif
  71
  72 extern void *vmalloc(unsigned long size);
  73 extern void *vzalloc(unsigned long size);
  74 extern void *vmalloc_user(unsigned long size);
  75 extern void *vmalloc_node(unsigned long size, int node);
  76 extern void *vzalloc_node(unsigned long size, int node);
  77 extern void *vmalloc_exec(unsigned long size);
  78 extern void *vmalloc_32(unsigned long size);
  79 extern void *vmalloc_32_user(unsigned long size);
  80 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
  81 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
  82                         unsigned long start, unsigned long end, gfp_t gfp_mask,
  83                         pgprot_t prot, unsigned long vm_flags, int node,
  84                         const void *caller);
  85 #ifndef CONFIG_MMU
  86 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
  87 static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
  88                                                 gfp_t flags, void *caller)
  89 {
  90         return __vmalloc_node_flags(size, node, flags);
  91 }
  92 #else
  93 extern void *__vmalloc_node_flags_caller(unsigned long size,
  94                                          int node, gfp_t flags, void *caller);
  95 #endif
  96
  97 extern void vfree(const void *addr);
  98 extern void vfree_atomic(const void *addr);
  99
 100 extern void *vmap(struct page **pages, unsigned int count,
 101                         unsigned long flags, pgprot_t prot);
 102 extern void vunmap(const void *addr);
 103
 104 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
 105                                        unsigned long uaddr, void *kaddr,
 106                                        unsigned long size);
 107
 108 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
 109                                                         unsigned long pgoff);
 110 void vmalloc_sync_all(void);
 111
 112 /*
 113  *      Lowlevel-APIs (not for driver use!)
 114  */
 115
 116 static inline size_t get_vm_area_size(const struct vm_struct *area)
 117 {
 118         if (!(area->flags & VM_NO_GUARD))
 119                 /* return actual size without guard page */
 120                 return area->size - PAGE_SIZE;
 121         else
 122                 return area->size;
 123
 124 }
 125
 126 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
 127 extern struct vm_struct *get_vm_area_caller(unsigned long size,
 128                                         unsigned long flags, const void *caller);
 129 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
 130                                         unsigned long start, unsigned long end);
 131 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
 132                                         unsigned long flags,
 133                                         unsigned long start, unsigned long end,
 134                                         const void *caller);
 135 extern struct vm_struct *remove_vm_area(const void *addr);
 136 extern struct vm_struct *find_vm_area(const void *addr);
 137
 138 extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
 139                         struct page **pages);
 140 #ifdef CONFIG_MMU
 141 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
 142                                     pgprot_t prot, struct page **pages);
 143 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
 144 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
 145 #else
 146 static inline int
 147 map_kernel_range_noflush(unsigned long start, unsigned long size,
 148                         pgprot_t prot, struct page **pages)
 149 {
 150         return size >> PAGE_SHIFT;
 151 }
 152 static inline void
 153 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
 154 {
 155 }
 156 static inline void
 157 unmap_kernel_range(unsigned long addr, unsigned long size)
 158 {
 159 }
 160 #endif
 161
 162 /* Allocate/destroy a 'vmalloc' VM area. */
 163 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
 164 extern void free_vm_area(struct vm_struct *area);
 165
 166 /* for /dev/kmem */
 167 extern long vread(char *buf, char *addr, unsigned long count);
 168 extern long vwrite(char *buf, char *addr, unsigned long count);
 169
 170 /*
 171  *      Internals.  Dont't use..
 172  */
 173 extern struct list_head vmap_area_list;
 174 extern __init void vm_area_add_early(struct vm_struct *vm);
 175 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
 176
 177 #ifdef CONFIG_SMP
 178 # ifdef CONFIG_MMU
 179 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 180                                      const size_t *sizes, int nr_vms,
 181                                      size_t align);
 182
 183 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
 184 # else
 185 static inline struct vm_struct **
 186 pcpu_get_vm_areas(const unsigned long *offsets,
 187                 const size_t *sizes, int nr_vms,
 188                 size_t align)
 189 {
 190         return NULL;
 191 }
 192
 193 static inline void
 194 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
 195 {
 196 }
 197 # endif
 198 #endif
 199
 200 #ifdef CONFIG_MMU
 201 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
 202 #else
 203 #define VMALLOC_TOTAL 0UL
 204 #endif
 205
 206 int register_vmap_purge_notifier(struct notifier_block *nb);
 207 int unregister_vmap_purge_notifier(struct notifier_block *nb);
 208
 209 #endif /* _LINUX_VMALLOC_H */