xref: /linux-6.15/include/linux/vmalloc.h (revision bb4e9af0)
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_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
22 #define VM_NO_GUARD		0x00000040      /* don't add guard page */
23 #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
24 /*
25  * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
26  * vfree_atomic().
27  */
28 #define VM_FLUSH_RESET_PERMS	0x00000100      /* Reset direct map and flush TLB on unmap */
29 /* bits [20..32] reserved for arch specific ioremap internals */
30 
31 /*
32  * Maximum alignment for ioremap() regions.
33  * Can be overriden by arch-specific value.
34  */
35 #ifndef IOREMAP_MAX_ORDER
36 #define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
37 #endif
38 
39 struct vm_struct {
40 	struct vm_struct	*next;
41 	void			*addr;
42 	unsigned long		size;
43 	unsigned long		flags;
44 	struct page		**pages;
45 	unsigned int		nr_pages;
46 	phys_addr_t		phys_addr;
47 	const void		*caller;
48 };
49 
50 struct vmap_area {
51 	unsigned long va_start;
52 	unsigned long va_end;
53 
54 	/*
55 	 * Largest available free size in subtree.
56 	 */
57 	unsigned long subtree_max_size;
58 	unsigned long flags;
59 	struct rb_node rb_node;         /* address sorted rbtree */
60 	struct list_head list;          /* address sorted list */
61 	struct llist_node purge_list;    /* "lazy purge" list */
62 	struct vm_struct *vm;
63 };
64 
65 /*
66  *	Highlevel APIs for driver use
67  */
68 extern void vm_unmap_ram(const void *mem, unsigned int count);
69 extern void *vm_map_ram(struct page **pages, unsigned int count,
70 				int node, pgprot_t prot);
71 extern void vm_unmap_aliases(void);
72 
73 #ifdef CONFIG_MMU
74 extern void __init vmalloc_init(void);
75 extern unsigned long vmalloc_nr_pages(void);
76 #else
77 static inline void vmalloc_init(void)
78 {
79 }
80 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
81 #endif
82 
83 extern void *vmalloc(unsigned long size);
84 extern void *vzalloc(unsigned long size);
85 extern void *vmalloc_user(unsigned long size);
86 extern void *vmalloc_node(unsigned long size, int node);
87 extern void *vzalloc_node(unsigned long size, int node);
88 extern void *vmalloc_exec(unsigned long size);
89 extern void *vmalloc_32(unsigned long size);
90 extern void *vmalloc_32_user(unsigned long size);
91 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
92 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
93 			unsigned long start, unsigned long end, gfp_t gfp_mask,
94 			pgprot_t prot, unsigned long vm_flags, int node,
95 			const void *caller);
96 #ifndef CONFIG_MMU
97 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
98 static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
99 						gfp_t flags, void *caller)
100 {
101 	return __vmalloc_node_flags(size, node, flags);
102 }
103 #else
104 extern void *__vmalloc_node_flags_caller(unsigned long size,
105 					 int node, gfp_t flags, void *caller);
106 #endif
107 
108 extern void vfree(const void *addr);
109 extern void vfree_atomic(const void *addr);
110 
111 extern void *vmap(struct page **pages, unsigned int count,
112 			unsigned long flags, pgprot_t prot);
113 extern void vunmap(const void *addr);
114 
115 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
116 				       unsigned long uaddr, void *kaddr,
117 				       unsigned long size);
118 
119 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
120 							unsigned long pgoff);
121 void vmalloc_sync_all(void);
122 
123 /*
124  *	Lowlevel-APIs (not for driver use!)
125  */
126 
127 static inline size_t get_vm_area_size(const struct vm_struct *area)
128 {
129 	if (!(area->flags & VM_NO_GUARD))
130 		/* return actual size without guard page */
131 		return area->size - PAGE_SIZE;
132 	else
133 		return area->size;
134 
135 }
136 
137 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
138 extern struct vm_struct *get_vm_area_caller(unsigned long size,
139 					unsigned long flags, const void *caller);
140 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
141 					unsigned long start, unsigned long end);
142 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
143 					unsigned long flags,
144 					unsigned long start, unsigned long end,
145 					const void *caller);
146 extern struct vm_struct *remove_vm_area(const void *addr);
147 extern struct vm_struct *find_vm_area(const void *addr);
148 
149 extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
150 			struct page **pages);
151 #ifdef CONFIG_MMU
152 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
153 				    pgprot_t prot, struct page **pages);
154 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
155 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
156 static inline void set_vm_flush_reset_perms(void *addr)
157 {
158 	struct vm_struct *vm = find_vm_area(addr);
159 
160 	if (vm)
161 		vm->flags |= VM_FLUSH_RESET_PERMS;
162 }
163 #else
164 static inline int
165 map_kernel_range_noflush(unsigned long start, unsigned long size,
166 			pgprot_t prot, struct page **pages)
167 {
168 	return size >> PAGE_SHIFT;
169 }
170 static inline void
171 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
172 {
173 }
174 static inline void
175 unmap_kernel_range(unsigned long addr, unsigned long size)
176 {
177 }
178 static inline void set_vm_flush_reset_perms(void *addr)
179 {
180 }
181 #endif
182 
183 /* Allocate/destroy a 'vmalloc' VM area. */
184 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
185 extern void free_vm_area(struct vm_struct *area);
186 
187 /* for /dev/kmem */
188 extern long vread(char *buf, char *addr, unsigned long count);
189 extern long vwrite(char *buf, char *addr, unsigned long count);
190 
191 /*
192  *	Internals.  Dont't use..
193  */
194 extern struct list_head vmap_area_list;
195 extern __init void vm_area_add_early(struct vm_struct *vm);
196 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
197 
198 #ifdef CONFIG_SMP
199 # ifdef CONFIG_MMU
200 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
201 				     const size_t *sizes, int nr_vms,
202 				     size_t align);
203 
204 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
205 # else
206 static inline struct vm_struct **
207 pcpu_get_vm_areas(const unsigned long *offsets,
208 		const size_t *sizes, int nr_vms,
209 		size_t align)
210 {
211 	return NULL;
212 }
213 
214 static inline void
215 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
216 {
217 }
218 # endif
219 #endif
220 
221 #ifdef CONFIG_MMU
222 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
223 #else
224 #define VMALLOC_TOTAL 0UL
225 #endif
226 
227 int register_vmap_purge_notifier(struct notifier_block *nb);
228 int unregister_vmap_purge_notifier(struct notifier_block *nb);
229 
230 #endif /* _LINUX_VMALLOC_H */
231