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
15 struct vm_area_struct; /* vma defining user mapping in mm_types.h */
16 struct 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 #define VM_MAP_PUT_PAGES 0x00000100 /* put pages and free array in vfree */
28
29 /*
30 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
31 *
32 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
33 * shadow memory has been mapped. It's used to handle allocation errors so that
34 * we don't try to poision shadow on free if it was never allocated.
35 *
36 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
37 * determine which allocations need the module shadow freed.
38 */
39
40 /*
41 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
42 * vfree_atomic().
43 */
44 #define VM_FLUSH_RESET_PERMS 0x00000100 /* Reset direct map and flush TLB on unmap */
45
46 /* bits [20..32] reserved for arch specific ioremap internals */
47
48 /*
49 * Maximum alignment for ioremap() regions.
50 * Can be overriden by arch-specific value.
51 */
52 #ifndef IOREMAP_MAX_ORDER
53 #define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
54 #endif
55
56 struct vm_struct {
57 struct vm_struct *next;
58 void *addr;
59 unsigned long size;
60 unsigned long flags;
61 struct page **pages;
62 unsigned int nr_pages;
63 phys_addr_t phys_addr;
64 const void *caller;
65 };
66
67 struct vmap_area {
68 unsigned long va_start;
69 unsigned long va_end;
70
71 struct rb_node rb_node; /* address sorted rbtree */
72 struct list_head list; /* address sorted list */
73
74 /*
75 * The following three variables can be packed, because
76 * a vmap_area object is always one of the three states:
77 * 1) in "free" tree (root is vmap_area_root)
78 * 2) in "busy" tree (root is free_vmap_area_root)
79 * 3) in purge list (head is vmap_purge_list)
80 */
81 union {
82 unsigned long subtree_max_size; /* in "free" tree */
83 struct vm_struct *vm; /* in "busy" tree */
84 struct llist_node purge_list; /* in purge list */
85 };
86 };
87
88 /*
89 * Highlevel APIs for driver use
90 */
91 extern void vm_unmap_ram(const void *mem, unsigned int count);
92 extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
93 extern void vm_unmap_aliases(void);
94
95 #ifdef CONFIG_MMU
96 extern void __init vmalloc_init(void);
97 extern unsigned long vmalloc_nr_pages(void);
98 #else
vmalloc_init(void)99 static inline void vmalloc_init(void)
100 {
101 }
vmalloc_nr_pages(void)102 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
103 #endif
104
105 extern void *vmalloc(unsigned long size);
106 extern void *vzalloc(unsigned long size);
107 extern void *vmalloc_user(unsigned long size);
108 extern void *vmalloc_node(unsigned long size, int node);
109 extern void *vzalloc_node(unsigned long size, int node);
110 extern void *vmalloc_32(unsigned long size);
111 extern void *vmalloc_32_user(unsigned long size);
112 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
113 extern 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 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
118 int node, const void *caller);
119
120 extern void vfree(const void *addr);
121 extern void vfree_atomic(const void *addr);
122
123 extern void *vmap(struct page **pages, unsigned int count,
124 unsigned long flags, pgprot_t prot);
125 void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
126 extern void vunmap(const void *addr);
127
128 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
129 unsigned long uaddr, void *kaddr,
130 unsigned long pgoff, unsigned long size);
131
132 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
133 unsigned long pgoff);
134
135 /*
136 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
137 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
138 * needs to be called.
139 */
140 #ifndef ARCH_PAGE_TABLE_SYNC_MASK
141 #define ARCH_PAGE_TABLE_SYNC_MASK 0
142 #endif
143
144 /*
145 * There is no default implementation for arch_sync_kernel_mappings(). It is
146 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
147 * is 0.
148 */
149 void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
150
151 /*
152 * Lowlevel-APIs (not for driver use!)
153 */
154
get_vm_area_size(const struct vm_struct * area)155 static inline size_t get_vm_area_size(const struct vm_struct *area)
156 {
157 if (!(area->flags & VM_NO_GUARD))
158 /* return actual size without guard page */
159 return area->size - PAGE_SIZE;
160 else
161 return area->size;
162
163 }
164
165 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
166 extern struct vm_struct *get_vm_area_caller(unsigned long size,
167 unsigned long flags, const void *caller);
168 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
169 unsigned long flags,
170 unsigned long start, unsigned long end,
171 const void *caller);
172 void free_vm_area(struct vm_struct *area);
173 extern struct vm_struct *remove_vm_area(const void *addr);
174 extern struct vm_struct *find_vm_area(const void *addr);
175
176 #ifdef CONFIG_MMU
177 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
178 pgprot_t prot, struct page **pages);
179 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
180 struct page **pages);
181 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
182 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
set_vm_flush_reset_perms(void * addr)183 static inline void set_vm_flush_reset_perms(void *addr)
184 {
185 struct vm_struct *vm = find_vm_area(addr);
186
187 if (vm)
188 vm->flags |= VM_FLUSH_RESET_PERMS;
189 }
190 #else
191 static inline int
map_kernel_range_noflush(unsigned long start,unsigned long size,pgprot_t prot,struct page ** pages)192 map_kernel_range_noflush(unsigned long start, unsigned long size,
193 pgprot_t prot, struct page **pages)
194 {
195 return size >> PAGE_SHIFT;
196 }
197 #define map_kernel_range map_kernel_range_noflush
198 static inline void
unmap_kernel_range_noflush(unsigned long addr,unsigned long size)199 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
200 {
201 }
202 #define unmap_kernel_range unmap_kernel_range_noflush
set_vm_flush_reset_perms(void * addr)203 static inline void set_vm_flush_reset_perms(void *addr)
204 {
205 }
206 #endif
207
208 /* for /dev/kmem */
209 extern long vread(char *buf, char *addr, unsigned long count);
210 extern long vwrite(char *buf, char *addr, unsigned long count);
211
212 /*
213 * Internals. Dont't use..
214 */
215 extern struct list_head vmap_area_list;
216 extern __init void vm_area_add_early(struct vm_struct *vm);
217 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
218
219 #ifdef CONFIG_SMP
220 # ifdef CONFIG_MMU
221 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
222 const size_t *sizes, int nr_vms,
223 size_t align);
224
225 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
226 # else
227 static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long * offsets,const size_t * sizes,int nr_vms,size_t align)228 pcpu_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
235 static inline void
pcpu_free_vm_areas(struct vm_struct ** vms,int nr_vms)236 pcpu_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
248 int register_vmap_purge_notifier(struct notifier_block *nb);
249 int unregister_vmap_purge_notifier(struct notifier_block *nb);
250
251 #endif /* _LINUX_VMALLOC_H */
252
