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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
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_DMA_COHERENT 0x00000010 /* dma_alloc_coherent */
22#define VM_UNINITIALIZED 0x00000020 /* vm_struct is not fully initialized */
23#define VM_NO_GUARD 0x00000040 /* don't add guard page */
24#define VM_KASAN 0x00000080 /* has allocated kasan shadow memory */
25
26/*
27 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
28 *
29 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
30 * shadow memory has been mapped. It's used to handle allocation errors so that
31 * we don't try to poision shadow on free if it was never allocated.
32 *
33 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
34 * determine which allocations need the module shadow freed.
35 */
36
37/*
38 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
39 * vfree_atomic().
40 */
41#define VM_FLUSH_RESET_PERMS 0x00000100 /* Reset direct map and flush TLB on unmap */
42
43/* bits [20..32] reserved for arch specific ioremap internals */
44
45/*
46 * Maximum alignment for ioremap() regions.
47 * Can be overriden by arch-specific value.
48 */
49#ifndef IOREMAP_MAX_ORDER
50#define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
51#endif
52
53struct vm_struct {
54 struct vm_struct *next;
55 void *addr;
56 unsigned long size;
57 unsigned long flags;
58 struct page **pages;
59 unsigned int nr_pages;
60 phys_addr_t phys_addr;
61 const void *caller;
62};
63
64struct vmap_area {
65 unsigned long va_start;
66 unsigned long va_end;
67
68 struct rb_node rb_node; /* address sorted rbtree */
69 struct list_head list; /* address sorted list */
70
71 /*
72 * The following three variables can be packed, because
73 * a vmap_area object is always one of the three states:
74 * 1) in "free" tree (root is vmap_area_root)
75 * 2) in "busy" tree (root is free_vmap_area_root)
76 * 3) in purge list (head is vmap_purge_list)
77 */
78 union {
79 unsigned long subtree_max_size; /* in "free" tree */
80 struct vm_struct *vm; /* in "busy" tree */
81 struct llist_node purge_list; /* in purge list */
82 };
83};
84
85/*
86 * Highlevel APIs for driver use
87 */
88extern void vm_unmap_ram(const void *mem, unsigned int count);
89extern void *vm_map_ram(struct page **pages, unsigned int count,
90 int node, pgprot_t prot);
91extern void vm_unmap_aliases(void);
92
93#ifdef CONFIG_MMU
94extern void __init vmalloc_init(void);
95extern unsigned long vmalloc_nr_pages(void);
96#else
97static inline void vmalloc_init(void)
98{
99}
100static inline unsigned long vmalloc_nr_pages(void) { return 0; }
101#endif
102
103extern void *vmalloc(unsigned long size);
104extern void *vzalloc(unsigned long size);
105extern void *vmalloc_user(unsigned long size);
106extern void *vmalloc_node(unsigned long size, int node);
107extern void *vzalloc_node(unsigned long size, int node);
108extern void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags);
109extern void *vmalloc_exec(unsigned long size);
110extern void *vmalloc_32(unsigned long size);
111extern void *vmalloc_32_user(unsigned long size);
112extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
113extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
114 unsigned long start, unsigned long end, gfp_t gfp_mask,
115 pgprot_t prot, unsigned long vm_flags, int node,
116 const void *caller);
117#ifndef CONFIG_MMU
118extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
119static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
120 gfp_t flags, void *caller)
121{
122 return __vmalloc_node_flags(size, node, flags);
123}
124#else
125extern void *__vmalloc_node_flags_caller(unsigned long size,
126 int node, gfp_t flags, void *caller);
127#endif
128
129extern void vfree(const void *addr);
130extern void vfree_atomic(const void *addr);
131
132extern void *vmap(struct page **pages, unsigned int count,
133 unsigned long flags, pgprot_t prot);
134extern void vunmap(const void *addr);
135
136extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
137 unsigned long uaddr, void *kaddr,
138 unsigned long size);
139
140extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
141 unsigned long pgoff);
142void vmalloc_sync_all(void);
143
144/*
145 * Lowlevel-APIs (not for driver use!)
146 */
147
148static inline size_t get_vm_area_size(const struct vm_struct *area)
149{
150 if (!(area->flags & VM_NO_GUARD))
151 /* return actual size without guard page */
152 return area->size - PAGE_SIZE;
153 else
154 return area->size;
155
156}
157
158extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
159extern struct vm_struct *get_vm_area_caller(unsigned long size,
160 unsigned long flags, const void *caller);
161extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
162 unsigned long start, unsigned long end);
163extern struct vm_struct *__get_vm_area_caller(unsigned long size,
164 unsigned long flags,
165 unsigned long start, unsigned long end,
166 const void *caller);
167extern struct vm_struct *remove_vm_area(const void *addr);
168extern struct vm_struct *find_vm_area(const void *addr);
169
170extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
171 struct page **pages);
172#ifdef CONFIG_MMU
173extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
174 pgprot_t prot, struct page **pages);
175extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
176extern void unmap_kernel_range(unsigned long addr, unsigned long size);
177static inline void set_vm_flush_reset_perms(void *addr)
178{
179 struct vm_struct *vm = find_vm_area(addr);
180
181 if (vm)
182 vm->flags |= VM_FLUSH_RESET_PERMS;
183}
184#else
185static inline int
186map_kernel_range_noflush(unsigned long start, unsigned long size,
187 pgprot_t prot, struct page **pages)
188{
189 return size >> PAGE_SHIFT;
190}
191static inline void
192unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
193{
194}
195static inline void
196unmap_kernel_range(unsigned long addr, unsigned long size)
197{
198}
199static inline void set_vm_flush_reset_perms(void *addr)
200{
201}
202#endif
203
204/* Allocate/destroy a 'vmalloc' VM area. */
205extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
206extern void free_vm_area(struct vm_struct *area);
207
208/* for /dev/kmem */
209extern long vread(char *buf, char *addr, unsigned long count);
210extern long vwrite(char *buf, char *addr, unsigned long count);
211
212/*
213 * Internals. Dont't use..
214 */
215extern struct list_head vmap_area_list;
216extern __init void vm_area_add_early(struct vm_struct *vm);
217extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
218
219#ifdef CONFIG_SMP
220# ifdef CONFIG_MMU
221struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
222 const size_t *sizes, int nr_vms,
223 size_t align);
224
225void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
226# else
227static inline struct vm_struct **
228pcpu_get_vm_areas(const unsigned long *offsets,
229 const size_t *sizes, int nr_vms,
230 size_t align)
231{
232 return NULL;
233}
234
235static inline void
236pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
237{
238}
239# endif
240#endif
241
242#ifdef CONFIG_MMU
243#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
244#else
245#define VMALLOC_TOTAL 0UL
246#endif
247
248int register_vmap_purge_notifier(struct notifier_block *nb);
249int unregister_vmap_purge_notifier(struct notifier_block *nb);
250
251#endif /* _LINUX_VMALLOC_H */