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_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 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
27 * vfree_atomic().
28 */
29 #define VM_FLUSH_RESET_PERMS 0x00000100 /* Reset direct map and flush TLB on unmap */
30
31 /* bits [20..32] reserved for arch specific ioremap internals */
32
33 /*
34 * Maximum alignment for ioremap() regions.
35 * Can be overriden by arch-specific value.
36 */
37 #ifndef IOREMAP_MAX_ORDER
38 #define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
39 #endif
40
41 struct vm_struct {
42 struct vm_struct *next;
43 void *addr;
44 unsigned long size;
45 unsigned long flags;
46 struct page **pages;
47 unsigned int nr_pages;
48 phys_addr_t phys_addr;
49 const void *caller;
50 };
51
52 struct vmap_area {
53 unsigned long va_start;
54 unsigned long va_end;
55
56 struct rb_node rb_node; /* address sorted rbtree */
57 struct list_head list; /* address sorted list */
58
59 /*
60 * The following three variables can be packed, because
61 * a vmap_area object is always one of the three states:
62 * 1) in "free" tree (root is vmap_area_root)
63 * 2) in "busy" tree (root is free_vmap_area_root)
64 * 3) in purge list (head is vmap_purge_list)
65 */
66 union {
67 unsigned long subtree_max_size; /* in "free" tree */
68 struct vm_struct *vm; /* in "busy" tree */
69 struct llist_node purge_list; /* in purge list */
70 };
71 };
72
73 /*
74 * Highlevel APIs for driver use
75 */
76 extern void vm_unmap_ram(const void *mem, unsigned int count);
77 extern void *vm_map_ram(struct page **pages, unsigned int count,
78 int node, pgprot_t prot);
79 extern void vm_unmap_aliases(void);
80
81 #ifdef CONFIG_MMU
82 extern void __init vmalloc_init(void);
83 extern unsigned long vmalloc_nr_pages(void);
84 #else
vmalloc_init(void)85 static inline void vmalloc_init(void)
86 {
87 }
vmalloc_nr_pages(void)88 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
89 #endif
90
91 extern void *vmalloc(unsigned long size);
92 extern void *vzalloc(unsigned long size);
93 extern void *vmalloc_user(unsigned long size);
94 extern void *vmalloc_node(unsigned long size, int node);
95 extern void *vzalloc_node(unsigned long size, int node);
96 extern void *vmalloc_exec(unsigned long size);
97 extern void *vmalloc_32(unsigned long size);
98 extern void *vmalloc_32_user(unsigned long size);
99 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
100 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
101 unsigned long start, unsigned long end, gfp_t gfp_mask,
102 pgprot_t prot, unsigned long vm_flags, int node,
103 const void *caller);
104 #ifndef CONFIG_MMU
105 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
__vmalloc_node_flags_caller(unsigned long size,int node,gfp_t flags,void * caller)106 static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
107 gfp_t flags, void *caller)
108 {
109 return __vmalloc_node_flags(size, node, flags);
110 }
111 #else
112 extern void *__vmalloc_node_flags_caller(unsigned long size,
113 int node, gfp_t flags, void *caller);
114 #endif
115
116 extern void vfree(const void *addr);
117 extern void vfree_atomic(const void *addr);
118
119 extern void *vmap(struct page **pages, unsigned int count,
120 unsigned long flags, pgprot_t prot);
121 extern void vunmap(const void *addr);
122
123 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
124 unsigned long uaddr, void *kaddr,
125 unsigned long pgoff, unsigned long size);
126
127 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
128 unsigned long pgoff);
129 void vmalloc_sync_mappings(void);
130 void vmalloc_sync_unmappings(void);
131
132 /*
133 * Lowlevel-APIs (not for driver use!)
134 */
135
get_vm_area_size(const struct vm_struct * area)136 static inline size_t get_vm_area_size(const struct vm_struct *area)
137 {
138 if (!(area->flags & VM_NO_GUARD))
139 /* return actual size without guard page */
140 return area->size - PAGE_SIZE;
141 else
142 return area->size;
143
144 }
145
146 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
147 extern struct vm_struct *get_vm_area_caller(unsigned long size,
148 unsigned long flags, const void *caller);
149 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
150 unsigned long start, unsigned long end);
151 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
152 unsigned long flags,
153 unsigned long start, unsigned long end,
154 const void *caller);
155 extern struct vm_struct *remove_vm_area(const void *addr);
156 extern struct vm_struct *find_vm_area(const void *addr);
157
158 extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
159 struct page **pages);
160 #ifdef CONFIG_MMU
161 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
162 pgprot_t prot, struct page **pages);
163 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
164 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
set_vm_flush_reset_perms(void * addr)165 static inline void set_vm_flush_reset_perms(void *addr)
166 {
167 struct vm_struct *vm = find_vm_area(addr);
168
169 if (vm)
170 vm->flags |= VM_FLUSH_RESET_PERMS;
171 }
172 #else
173 static inline int
map_kernel_range_noflush(unsigned long start,unsigned long size,pgprot_t prot,struct page ** pages)174 map_kernel_range_noflush(unsigned long start, unsigned long size,
175 pgprot_t prot, struct page **pages)
176 {
177 return size >> PAGE_SHIFT;
178 }
179 static inline void
unmap_kernel_range_noflush(unsigned long addr,unsigned long size)180 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
181 {
182 }
183 static inline void
unmap_kernel_range(unsigned long addr,unsigned long size)184 unmap_kernel_range(unsigned long addr, unsigned long size)
185 {
186 }
set_vm_flush_reset_perms(void * addr)187 static inline void set_vm_flush_reset_perms(void *addr)
188 {
189 }
190 #endif
191
192 /* Allocate/destroy a 'vmalloc' VM area. */
193 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
194 extern void free_vm_area(struct vm_struct *area);
195
196 /* for /dev/kmem */
197 extern long vread(char *buf, char *addr, unsigned long count);
198 extern long vwrite(char *buf, char *addr, unsigned long count);
199
200 /*
201 * Internals. Dont't use..
202 */
203 extern struct list_head vmap_area_list;
204 extern __init void vm_area_add_early(struct vm_struct *vm);
205 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
206
207 #ifdef CONFIG_SMP
208 # ifdef CONFIG_MMU
209 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
210 const size_t *sizes, int nr_vms,
211 size_t align);
212
213 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
214 # else
215 static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long * offsets,const size_t * sizes,int nr_vms,size_t align)216 pcpu_get_vm_areas(const unsigned long *offsets,
217 const size_t *sizes, int nr_vms,
218 size_t align)
219 {
220 return NULL;
221 }
222
223 static inline void
pcpu_free_vm_areas(struct vm_struct ** vms,int nr_vms)224 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
225 {
226 }
227 # endif
228 #endif
229
230 #ifdef CONFIG_MMU
231 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
232 #else
233 #define VMALLOC_TOTAL 0UL
234 #endif
235
236 int register_vmap_purge_notifier(struct notifier_block *nb);
237 int unregister_vmap_purge_notifier(struct notifier_block *nb);
238
239 #endif /* _LINUX_VMALLOC_H */
240