xref: /linux-6.15/include/linux/vmalloc.h (revision 5e29a910)
1 #ifndef _LINUX_VMALLOC_H
2 #define _LINUX_VMALLOC_H
3 
4 #include <linux/spinlock.h>
5 #include <linux/init.h>
6 #include <linux/list.h>
7 #include <asm/page.h>		/* pgprot_t */
8 #include <linux/rbtree.h>
9 
10 struct vm_area_struct;		/* vma defining user mapping in mm_types.h */
11 
12 /* bits in flags of vmalloc's vm_struct below */
13 #define VM_IOREMAP		0x00000001	/* ioremap() and friends */
14 #define VM_ALLOC		0x00000002	/* vmalloc() */
15 #define VM_MAP			0x00000004	/* vmap()ed pages */
16 #define VM_USERMAP		0x00000008	/* suitable for remap_vmalloc_range */
17 #define VM_VPAGES		0x00000010	/* buffer for pages was vmalloc'ed */
18 #define VM_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
19 #define VM_NO_GUARD		0x00000040      /* don't add guard page */
20 /* bits [20..32] reserved for arch specific ioremap internals */
21 
22 /*
23  * Maximum alignment for ioremap() regions.
24  * Can be overriden by arch-specific value.
25  */
26 #ifndef IOREMAP_MAX_ORDER
27 #define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
28 #endif
29 
30 struct vm_struct {
31 	struct vm_struct	*next;
32 	void			*addr;
33 	unsigned long		size;
34 	unsigned long		flags;
35 	struct page		**pages;
36 	unsigned int		nr_pages;
37 	phys_addr_t		phys_addr;
38 	const void		*caller;
39 };
40 
41 struct vmap_area {
42 	unsigned long va_start;
43 	unsigned long va_end;
44 	unsigned long flags;
45 	struct rb_node rb_node;         /* address sorted rbtree */
46 	struct list_head list;          /* address sorted list */
47 	struct list_head purge_list;    /* "lazy purge" list */
48 	struct vm_struct *vm;
49 	struct rcu_head rcu_head;
50 };
51 
52 /*
53  *	Highlevel APIs for driver use
54  */
55 extern void vm_unmap_ram(const void *mem, unsigned int count);
56 extern void *vm_map_ram(struct page **pages, unsigned int count,
57 				int node, pgprot_t prot);
58 extern void vm_unmap_aliases(void);
59 
60 #ifdef CONFIG_MMU
61 extern void __init vmalloc_init(void);
62 #else
63 static inline void vmalloc_init(void)
64 {
65 }
66 #endif
67 
68 extern void *vmalloc(unsigned long size);
69 extern void *vzalloc(unsigned long size);
70 extern void *vmalloc_user(unsigned long size);
71 extern void *vmalloc_node(unsigned long size, int node);
72 extern void *vzalloc_node(unsigned long size, int node);
73 extern void *vmalloc_exec(unsigned long size);
74 extern void *vmalloc_32(unsigned long size);
75 extern void *vmalloc_32_user(unsigned long size);
76 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
77 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
78 			unsigned long start, unsigned long end, gfp_t gfp_mask,
79 			pgprot_t prot, unsigned long vm_flags, int node,
80 			const void *caller);
81 
82 extern void vfree(const void *addr);
83 
84 extern void *vmap(struct page **pages, unsigned int count,
85 			unsigned long flags, pgprot_t prot);
86 extern void vunmap(const void *addr);
87 
88 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
89 				       unsigned long uaddr, void *kaddr,
90 				       unsigned long size);
91 
92 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
93 							unsigned long pgoff);
94 void vmalloc_sync_all(void);
95 
96 /*
97  *	Lowlevel-APIs (not for driver use!)
98  */
99 
100 static inline size_t get_vm_area_size(const struct vm_struct *area)
101 {
102 	if (!(area->flags & VM_NO_GUARD))
103 		/* return actual size without guard page */
104 		return area->size - PAGE_SIZE;
105 	else
106 		return area->size;
107 
108 }
109 
110 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
111 extern struct vm_struct *get_vm_area_caller(unsigned long size,
112 					unsigned long flags, const void *caller);
113 extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
114 					unsigned long start, unsigned long end);
115 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
116 					unsigned long flags,
117 					unsigned long start, unsigned long end,
118 					const void *caller);
119 extern struct vm_struct *remove_vm_area(const void *addr);
120 extern struct vm_struct *find_vm_area(const void *addr);
121 
122 extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
123 			struct page **pages);
124 #ifdef CONFIG_MMU
125 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
126 				    pgprot_t prot, struct page **pages);
127 extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
128 extern void unmap_kernel_range(unsigned long addr, unsigned long size);
129 #else
130 static inline int
131 map_kernel_range_noflush(unsigned long start, unsigned long size,
132 			pgprot_t prot, struct page **pages)
133 {
134 	return size >> PAGE_SHIFT;
135 }
136 static inline void
137 unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
138 {
139 }
140 static inline void
141 unmap_kernel_range(unsigned long addr, unsigned long size)
142 {
143 }
144 #endif
145 
146 /* Allocate/destroy a 'vmalloc' VM area. */
147 extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
148 extern void free_vm_area(struct vm_struct *area);
149 
150 /* for /dev/kmem */
151 extern long vread(char *buf, char *addr, unsigned long count);
152 extern long vwrite(char *buf, char *addr, unsigned long count);
153 
154 /*
155  *	Internals.  Dont't use..
156  */
157 extern struct list_head vmap_area_list;
158 extern __init void vm_area_add_early(struct vm_struct *vm);
159 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
160 
161 #ifdef CONFIG_SMP
162 # ifdef CONFIG_MMU
163 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
164 				     const size_t *sizes, int nr_vms,
165 				     size_t align);
166 
167 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
168 # else
169 static inline struct vm_struct **
170 pcpu_get_vm_areas(const unsigned long *offsets,
171 		const size_t *sizes, int nr_vms,
172 		size_t align)
173 {
174 	return NULL;
175 }
176 
177 static inline void
178 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
179 {
180 }
181 # endif
182 #endif
183 
184 struct vmalloc_info {
185 	unsigned long   used;
186 	unsigned long   largest_chunk;
187 };
188 
189 #ifdef CONFIG_MMU
190 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
191 extern void get_vmalloc_info(struct vmalloc_info *vmi);
192 #else
193 
194 #define VMALLOC_TOTAL 0UL
195 #define get_vmalloc_info(vmi)			\
196 do {						\
197 	(vmi)->used = 0;			\
198 	(vmi)->largest_chunk = 0;		\
199 } while (0)
200 #endif
201 
202 #endif /* _LINUX_VMALLOC_H */
203