xref: /linux-6.15/include/linux/vmalloc.h (revision 8b0e1fea)
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 	unsigned long flags;
54 	struct rb_node rb_node;         /* address sorted rbtree */
55 	struct list_head list;          /* address sorted list */
56 	struct llist_node purge_list;    /* "lazy purge" list */
57 	struct vm_struct *vm;
58 	struct rcu_head rcu_head;
59 };
60 
61 /*
62  *	Highlevel APIs for driver use
63  */
64 extern void vm_unmap_ram(const void *mem, unsigned int count);
65 extern void *vm_map_ram(struct page **pages, unsigned int count,
66 				int node, pgprot_t prot);
67 extern void vm_unmap_aliases(void);
68 
69 #ifdef CONFIG_MMU
70 extern void __init vmalloc_init(void);
71 #else
72 static inline void vmalloc_init(void)
73 {
74 }
75 #endif
76 
77 extern void *vmalloc(unsigned long size);
78 extern void *vzalloc(unsigned long size);
79 extern void *vmalloc_user(unsigned long size);
80 extern void *vmalloc_node(unsigned long size, int node);
81 extern void *vzalloc_node(unsigned long size, int node);
82 extern void *vmalloc_exec(unsigned long size);
83 extern void *vmalloc_32(unsigned long size);
84 extern void *vmalloc_32_user(unsigned long size);
85 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
86 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
87 			unsigned long start, unsigned long end, gfp_t gfp_mask,
88 			pgprot_t prot, unsigned long vm_flags, int node,
89 			const void *caller);
90 #ifndef CONFIG_MMU
91 extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
92 static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
93 						gfp_t flags, void *caller)
94 {
95 	return __vmalloc_node_flags(size, node, flags);
96 }
97 #else
98 extern void *__vmalloc_node_flags_caller(unsigned long size,
99 					 int node, gfp_t flags, void *caller);
100 #endif
101 
102 extern void vfree(const void *addr);
103 extern void vfree_atomic(const void *addr);
104 
105 extern void *vmap(struct page **pages, unsigned int count,
106 			unsigned long flags, pgprot_t prot);
107 extern void vunmap(const void *addr);
108 
109 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
110 				       unsigned long uaddr, void *kaddr,
111 				       unsigned long size);
112 
113 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
114 							unsigned long pgoff);
115 void vmalloc_sync_all(void);
116 
117 /*
118  *	Lowlevel-APIs (not for driver use!)
119  */
120 
121 static inline size_t get_vm_area_size(const struct vm_struct *area)
122 {
123 	if (!(area->flags & VM_NO_GUARD))
124 		/* return actual size without guard page */
125 		return area->size - PAGE_SIZE;
126 	else
127 		return area->size;
128 
129 }
130 
131 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
132 extern struct vm_struct *get_vm_area_caller(unsigned long size,
133 					unsigned long flags, const void *caller);
134 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
135 					unsigned long start, unsigned long end);
136 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
137 					unsigned long flags,
138 					unsigned long start, unsigned long end,
139 					const void *caller);
140 extern struct vm_struct *remove_vm_area(const void *addr);
141 extern struct vm_struct *find_vm_area(const void *addr);
142 
143 extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
144 			struct page **pages);
145 #ifdef CONFIG_MMU
146 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
147 				    pgprot_t prot, struct page **pages);
148 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
149 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
150 static inline void set_vm_flush_reset_perms(void *addr)
151 {
152 	struct vm_struct *vm = find_vm_area(addr);
153 
154 	if (vm)
155 		vm->flags |= VM_FLUSH_RESET_PERMS;
156 }
157 #else
158 static inline int
159 map_kernel_range_noflush(unsigned long start, unsigned long size,
160 			pgprot_t prot, struct page **pages)
161 {
162 	return size >> PAGE_SHIFT;
163 }
164 static inline void
165 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
166 {
167 }
168 static inline void
169 unmap_kernel_range(unsigned long addr, unsigned long size)
170 {
171 }
172 static inline void set_vm_flush_reset_perms(void *addr)
173 {
174 }
175 #endif
176 
177 /* Allocate/destroy a 'vmalloc' VM area. */
178 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
179 extern void free_vm_area(struct vm_struct *area);
180 
181 /* for /dev/kmem */
182 extern long vread(char *buf, char *addr, unsigned long count);
183 extern long vwrite(char *buf, char *addr, unsigned long count);
184 
185 /*
186  *	Internals.  Dont't use..
187  */
188 extern struct list_head vmap_area_list;
189 extern __init void vm_area_add_early(struct vm_struct *vm);
190 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
191 
192 #ifdef CONFIG_SMP
193 # ifdef CONFIG_MMU
194 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
195 				     const size_t *sizes, int nr_vms,
196 				     size_t align);
197 
198 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
199 # else
200 static inline struct vm_struct **
201 pcpu_get_vm_areas(const unsigned long *offsets,
202 		const size_t *sizes, int nr_vms,
203 		size_t align)
204 {
205 	return NULL;
206 }
207 
208 static inline void
209 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
210 {
211 }
212 # endif
213 #endif
214 
215 #ifdef CONFIG_MMU
216 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
217 #else
218 #define VMALLOC_TOTAL 0UL
219 #endif
220 
221 int register_vmap_purge_notifier(struct notifier_block *nb);
222 int unregister_vmap_purge_notifier(struct notifier_block *nb);
223 
224 #endif /* _LINUX_VMALLOC_H */
225