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_FLUSH_RESET_PERMS 0x00000100 /* reset direct map and flush TLB on unmap, can't be freed in atomic context */
28 #define VM_MAP_PUT_PAGES 0x00000200 /* put pages and free array in vfree */
29
30 /*
31 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
32 *
33 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
34 * shadow memory has been mapped. It's used to handle allocation errors so that
35 * we don't try to poision shadow on free if it was never allocated.
36 *
37 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
38 * determine which allocations need the module shadow freed.
39 */
40
41 /* bits [20..32] reserved for arch specific ioremap internals */
42
43 /*
44 * Maximum alignment for ioremap() regions.
45 * Can be overriden by arch-specific value.
46 */
47 #ifndef IOREMAP_MAX_ORDER
48 #define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
49 #endif
50
51 struct vm_struct {
52 struct vm_struct *next;
53 void *addr;
54 unsigned long size;
55 unsigned long flags;
56 struct page **pages;
57 unsigned int nr_pages;
58 phys_addr_t phys_addr;
59 const void *caller;
60 };
61
62 struct vmap_area {
63 unsigned long va_start;
64 unsigned long va_end;
65
66 struct rb_node rb_node; /* address sorted rbtree */
67 struct list_head list; /* address sorted list */
68
69 /*
70 * The following three variables can be packed, because
71 * a vmap_area object is always one of the three states:
72 * 1) in "free" tree (root is vmap_area_root)
73 * 2) in "busy" tree (root is free_vmap_area_root)
74 * 3) in purge list (head is vmap_purge_list)
75 */
76 union {
77 unsigned long subtree_max_size; /* in "free" tree */
78 struct vm_struct *vm; /* in "busy" tree */
79 struct llist_node purge_list; /* in purge list */
80 };
81 };
82
83 /*
84 * Highlevel APIs for driver use
85 */
86 extern void vm_unmap_ram(const void *mem, unsigned int count);
87 extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
88 extern void vm_unmap_aliases(void);
89
90 #ifdef CONFIG_MMU
91 extern void __init vmalloc_init(void);
92 extern unsigned long vmalloc_nr_pages(void);
93 #else
vmalloc_init(void)94 static inline void vmalloc_init(void)
95 {
96 }
vmalloc_nr_pages(void)97 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
98 #endif
99
100 extern void *vmalloc(unsigned long size);
101 extern void *vzalloc(unsigned long size);
102 extern void *vmalloc_user(unsigned long size);
103 extern void *vmalloc_node(unsigned long size, int node);
104 extern void *vzalloc_node(unsigned long size, int node);
105 extern void *vmalloc_32(unsigned long size);
106 extern void *vmalloc_32_user(unsigned long size);
107 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
108 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
109 unsigned long start, unsigned long end, gfp_t gfp_mask,
110 pgprot_t prot, unsigned long vm_flags, int node,
111 const void *caller);
112 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
113 int node, const void *caller);
114
115 extern void vfree(const void *addr);
116 extern void vfree_atomic(const void *addr);
117
118 extern void *vmap(struct page **pages, unsigned int count,
119 unsigned long flags, pgprot_t prot);
120 void *vmap_pfn(unsigned long *pfns, unsigned int count, 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
130 /*
131 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
132 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
133 * needs to be called.
134 */
135 #ifndef ARCH_PAGE_TABLE_SYNC_MASK
136 #define ARCH_PAGE_TABLE_SYNC_MASK 0
137 #endif
138
139 /*
140 * There is no default implementation for arch_sync_kernel_mappings(). It is
141 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
142 * is 0.
143 */
144 void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
145
146 /*
147 * Lowlevel-APIs (not for driver use!)
148 */
149
get_vm_area_size(const struct vm_struct * area)150 static inline size_t get_vm_area_size(const struct vm_struct *area)
151 {
152 if (!(area->flags & VM_NO_GUARD))
153 /* return actual size without guard page */
154 return area->size - PAGE_SIZE;
155 else
156 return area->size;
157
158 }
159
160 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
161 extern struct vm_struct *get_vm_area_caller(unsigned long size,
162 unsigned long flags, const void *caller);
163 extern 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);
167 void free_vm_area(struct vm_struct *area);
168 extern struct vm_struct *remove_vm_area(const void *addr);
169 extern struct vm_struct *find_vm_area(const void *addr);
170
171 #ifdef CONFIG_MMU
172 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
173 pgprot_t prot, struct page **pages);
174 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
175 struct page **pages);
176 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
177 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
set_vm_flush_reset_perms(void * addr)178 static inline void set_vm_flush_reset_perms(void *addr)
179 {
180 struct vm_struct *vm = find_vm_area(addr);
181
182 if (vm)
183 vm->flags |= VM_FLUSH_RESET_PERMS;
184 }
185 #else
186 static inline int
map_kernel_range_noflush(unsigned long start,unsigned long size,pgprot_t prot,struct page ** pages)187 map_kernel_range_noflush(unsigned long start, unsigned long size,
188 pgprot_t prot, struct page **pages)
189 {
190 return size >> PAGE_SHIFT;
191 }
192 #define map_kernel_range map_kernel_range_noflush
193 static inline void
unmap_kernel_range_noflush(unsigned long addr,unsigned long size)194 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
195 {
196 }
197 #define unmap_kernel_range unmap_kernel_range_noflush
set_vm_flush_reset_perms(void * addr)198 static inline void set_vm_flush_reset_perms(void *addr)
199 {
200 }
201 #endif
202
203 /* for /dev/kmem */
204 extern long vread(char *buf, char *addr, unsigned long count);
205 extern long vwrite(char *buf, char *addr, unsigned long count);
206
207 /*
208 * Internals. Dont't use..
209 */
210 extern struct list_head vmap_area_list;
211 extern __init void vm_area_add_early(struct vm_struct *vm);
212 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
213
214 #ifdef CONFIG_SMP
215 # ifdef CONFIG_MMU
216 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
217 const size_t *sizes, int nr_vms,
218 size_t align);
219
220 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
221 # else
222 static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long * offsets,const size_t * sizes,int nr_vms,size_t align)223 pcpu_get_vm_areas(const unsigned long *offsets,
224 const size_t *sizes, int nr_vms,
225 size_t align)
226 {
227 return NULL;
228 }
229
230 static inline void
pcpu_free_vm_areas(struct vm_struct ** vms,int nr_vms)231 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
232 {
233 }
234 # endif
235 #endif
236
237 #ifdef CONFIG_MMU
238 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
239 #else
240 #define VMALLOC_TOTAL 0UL
241 #endif
242
243 int register_vmap_purge_notifier(struct notifier_block *nb);
244 int unregister_vmap_purge_notifier(struct notifier_block *nb);
245
246 #endif /* _LINUX_VMALLOC_H */
247