LXR linux/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
  13struct vm_area_struct;          /* vma defining user mapping in mm_types.h */
  14struct 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/*
  25 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
  26 * vfree_atomic().
  27 */
  28#define VM_FLUSH_RESET_PERMS    0x00000100      /* Reset direct map and flush TLB on unmap */
  29/* bits [20..32] reserved for arch specific ioremap internals */
  30
  31/*
  32 * Maximum alignment for ioremap() regions.
  33 * Can be overriden by arch-specific value.
  34 */
  35#ifndef IOREMAP_MAX_ORDER
  36#define IOREMAP_MAX_ORDER       (7 + PAGE_SHIFT)        /* 128 pages */
  37#endif
  38
  39struct vm_struct {
  40        struct vm_struct        *next;
  41        void                    *addr;
  42        unsigned long           size;
  43        unsigned long           flags;
  44        struct page             **pages;
  45        unsigned int            nr_pages;
  46        phys_addr_t             phys_addr;
  47        const void              *caller;
  48};
  49
  50struct vmap_area {
  51        unsigned long va_start;
  52        unsigned long va_end;
  53
  54        /*
  55         * Largest available free size in subtree.
  56         */
  57        unsigned long subtree_max_size;
  58        unsigned long flags;
  59        struct rb_node rb_node;         /* address sorted rbtree */
  60        struct list_head list;          /* address sorted list */
  61        struct llist_node purge_list;    /* "lazy purge" list */
  62        struct vm_struct *vm;
  63};
  64
  65/*
  66 *      Highlevel APIs for driver use
  67 */
  68extern void vm_unmap_ram(const void *mem, unsigned int count);
  69extern void *vm_map_ram(struct page **pages, unsigned int count,
  70                                int node, pgprot_t prot);
  71extern void vm_unmap_aliases(void);
  72
  73#ifdef CONFIG_MMU
  74extern void __init vmalloc_init(void);
  75#else
  76static inline void vmalloc_init(void)
  77{
  78}
  79#endif
  80
  81extern void *vmalloc(unsigned long size);
  82extern void *vzalloc(unsigned long size);
  83extern void *vmalloc_user(unsigned long size);
  84extern void *vmalloc_node(unsigned long size, int node);
  85extern void *vzalloc_node(unsigned long size, int node);
  86extern void *vmalloc_exec(unsigned long size);
  87extern void *vmalloc_32(unsigned long size);
  88extern void *vmalloc_32_user(unsigned long size);
  89extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
  90extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
  91                        unsigned long start, unsigned long end, gfp_t gfp_mask,
  92                        pgprot_t prot, unsigned long vm_flags, int node,
  93                        const void *caller);
  94#ifndef CONFIG_MMU
  95extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
  96static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
  97                                                gfp_t flags, void *caller)
  98{
  99        return __vmalloc_node_flags(size, node, flags);
 100}
 101#else
 102extern void *__vmalloc_node_flags_caller(unsigned long size,
 103                                         int node, gfp_t flags, void *caller);
 104#endif
 105
 106extern void vfree(const void *addr);
 107extern void vfree_atomic(const void *addr);
 108
 109extern void *vmap(struct page **pages, unsigned int count,
 110                        unsigned long flags, pgprot_t prot);
 111extern void vunmap(const void *addr);
 112
 113extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
 114                                       unsigned long uaddr, void *kaddr,
 115                                       unsigned long size);
 116
 117extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
 118                                                        unsigned long pgoff);
 119void vmalloc_sync_all(void);
 120 
 121/*
 122 *      Lowlevel-APIs (not for driver use!)
 123 */
 124
 125static inline size_t get_vm_area_size(const struct vm_struct *area)
 126{
 127        if (!(area->flags & VM_NO_GUARD))
 128                /* return actual size without guard page */
 129                return area->size - PAGE_SIZE;
 130        else
 131                return area->size;
 132
 133}
 134
 135extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
 136extern struct vm_struct *get_vm_area_caller(unsigned long size,
 137                                        unsigned long flags, const void *caller);
 138extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
 139                                        unsigned long start, unsigned long end);
 140extern struct vm_struct *__get_vm_area_caller(unsigned long size,
 141                                        unsigned long flags,
 142                                        unsigned long start, unsigned long end,
 143                                        const void *caller);
 144extern struct vm_struct *remove_vm_area(const void *addr);
 145extern struct vm_struct *find_vm_area(const void *addr);
 146
 147extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
 148                        struct page **pages);
 149#ifdef CONFIG_MMU
 150extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
 151                                    pgprot_t prot, struct page **pages);
 152extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
 153extern void unmap_kernel_range(unsigned long addr, unsigned long size);
 154static inline void set_vm_flush_reset_perms(void *addr)
 155{
 156        struct vm_struct *vm = find_vm_area(addr);
 157
 158        if (vm)
 159                vm->flags |= VM_FLUSH_RESET_PERMS;
 160}
 161#else
 162static inline int
 163map_kernel_range_noflush(unsigned long start, unsigned long size,
 164                        pgprot_t prot, struct page **pages)
 165{
 166        return size >> PAGE_SHIFT;
 167}
 168static inline void
 169unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
 170{
 171}
 172static inline void
 173unmap_kernel_range(unsigned long addr, unsigned long size)
 174{
 175}
 176static inline void set_vm_flush_reset_perms(void *addr)
 177{
 178}
 179#endif
 180
 181/* Allocate/destroy a 'vmalloc' VM area. */
 182extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
 183extern void free_vm_area(struct vm_struct *area);
 184
 185/* for /dev/kmem */
 186extern long vread(char *buf, char *addr, unsigned long count);
 187extern long vwrite(char *buf, char *addr, unsigned long count);
 188
 189/*
 190 *      Internals.  Dont't use..
 191 */
 192extern struct list_head vmap_area_list;
 193extern __init void vm_area_add_early(struct vm_struct *vm);
 194extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
 195
 196#ifdef CONFIG_SMP
 197# ifdef CONFIG_MMU
 198struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 199                                     const size_t *sizes, int nr_vms,
 200                                     size_t align);
 201
 202void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
 203# else
 204static inline struct vm_struct **
 205pcpu_get_vm_areas(const unsigned long *offsets,
 206                const size_t *sizes, int nr_vms,
 207                size_t align)
 208{
 209        return NULL;
 210}
 211
 212static inline void
 213pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
 214{
 215}
 216# endif
 217#endif
 218
 219#ifdef CONFIG_MMU
 220#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
 221#else
 222#define VMALLOC_TOTAL 0UL
 223#endif
 224
 225int register_vmap_purge_notifier(struct notifier_block *nb);
 226int unregister_vmap_purge_notifier(struct notifier_block *nb);
 227
 228#endif /* _LINUX_VMALLOC_H */
 229