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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_mappings(void);
145void vmalloc_sync_unmappings(void);
146
147/*
148 * Lowlevel-APIs (not for driver use!)
149 */
150
151static inline size_t get_vm_area_size(const struct vm_struct *area)
152{
153 if (!(area->flags & VM_NO_GUARD))
154 /* return actual size without guard page */
155 return area->size - PAGE_SIZE;
156 else
157 return area->size;
158
159}
160
161extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
162extern struct vm_struct *get_vm_area_caller(unsigned long size,
163 unsigned long flags, const void *caller);
164extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
165 unsigned long start, unsigned long end);
166extern 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);
170extern struct vm_struct *remove_vm_area(const void *addr);
171extern struct vm_struct *find_vm_area(const void *addr);
172
173extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
174 struct page **pages);
175#ifdef CONFIG_MMU
176extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
177 pgprot_t prot, struct page **pages);
178extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
179extern void unmap_kernel_range(unsigned long addr, unsigned long size);
180static 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
188static inline int
189map_kernel_range_noflush(unsigned long start, unsigned long size,
190 pgprot_t prot, struct page **pages)
191{
192 return size >> PAGE_SHIFT;
193}
194static inline void
195unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
196{
197}
198static inline void
199unmap_kernel_range(unsigned long addr, unsigned long size)
200{
201}
202static inline void set_vm_flush_reset_perms(void *addr)
203{
204}
205#endif
206
207/* Allocate/destroy a 'vmalloc' VM area. */
208extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
209extern void free_vm_area(struct vm_struct *area);
210
211/* for /dev/kmem */
212extern long vread(char *buf, char *addr, unsigned long count);
213extern long vwrite(char *buf, char *addr, unsigned long count);
214
215/*
216 * Internals. Dont't use..
217 */
218extern struct list_head vmap_area_list;
219extern __init void vm_area_add_early(struct vm_struct *vm);
220extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
221
222#ifdef CONFIG_SMP
223# ifdef CONFIG_MMU
224struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
225 const size_t *sizes, int nr_vms,
226 size_t align);
227
228void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
229# else
230static inline struct vm_struct **
231pcpu_get_vm_areas(const unsigned long *offsets,
232 const size_t *sizes, int nr_vms,
233 size_t align)
234{
235 return NULL;
236}
237
238static inline void
239pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
240{
241}
242# endif
243#endif
244
245#ifdef CONFIG_MMU
246#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
247#else
248#define VMALLOC_TOTAL 0UL
249#endif
250
251int register_vmap_purge_notifier(struct notifier_block *nb);
252int unregister_vmap_purge_notifier(struct notifier_block *nb);
253
254#endif /* _LINUX_VMALLOC_H */