summaryrefslogtreecommitdiff
path: root/include/linux/vmalloc.h
blob: 0507a162ccd0e7ba4edf007654084effe3b5579a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_VMALLOC_H
#define _LINUX_VMALLOC_H

#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/llist.h>
#include <asm/page.h>		/* pgprot_t */
#include <linux/rbtree.h>
#include <linux/overflow.h>

#include <asm/vmalloc.h>

struct vm_area_struct;		/* vma defining user mapping in mm_types.h */
struct notifier_block;		/* in notifier.h */

/* bits in flags of vmalloc's vm_struct below */
#define VM_IOREMAP		0x00000001	/* ioremap() and friends */
#define VM_ALLOC		0x00000002	/* vmalloc() */
#define VM_MAP			0x00000004	/* vmap()ed pages */
#define VM_USERMAP		0x00000008	/* suitable for remap_vmalloc_range */
#define VM_DMA_COHERENT		0x00000010	/* dma_alloc_coherent */
#define VM_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
#define VM_NO_GUARD		0x00000040      /* don't add guard page */
#define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */

/*
 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
 *
 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
 * shadow memory has been mapped. It's used to handle allocation errors so that
 * we don't try to poision shadow on free if it was never allocated.
 *
 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
 * determine which allocations need the module shadow freed.
 */

/*
 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
 * vfree_atomic().
 */
#define VM_FLUSH_RESET_PERMS	0x00000100      /* Reset direct map and flush TLB on unmap */

/* bits [20..32] reserved for arch specific ioremap internals */

/*
 * Maximum alignment for ioremap() regions.
 * Can be overriden by arch-specific value.
 */
#ifndef IOREMAP_MAX_ORDER
#define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
#endif

struct vm_struct {
	struct vm_struct	*next;
	void			*addr;
	unsigned long		size;
	unsigned long		flags;
	struct page		**pages;
	unsigned int		nr_pages;
	phys_addr_t		phys_addr;
	const void		*caller;
};

struct vmap_area {
	unsigned long va_start;
	unsigned long va_end;

	struct rb_node rb_node;         /* address sorted rbtree */
	struct list_head list;          /* address sorted list */

	/*
	 * The following three variables can be packed, because
	 * a vmap_area object is always one of the three states:
	 *    1) in "free" tree (root is vmap_area_root)
	 *    2) in "busy" tree (root is free_vmap_area_root)
	 *    3) in purge list  (head is vmap_purge_list)
	 */
	union {
		unsigned long subtree_max_size; /* in "free" tree */
		struct vm_struct *vm;           /* in "busy" tree */
		struct llist_node purge_list;   /* in purge list */
	};
};

/*
 *	Highlevel APIs for driver use
 */
extern void vm_unmap_ram(const void *mem, unsigned int count);
extern void *vm_map_ram(struct page **pages, unsigned int count,
				int node, pgprot_t prot);
extern void vm_unmap_aliases(void);

#ifdef CONFIG_MMU
extern void __init vmalloc_init(void);
extern unsigned long vmalloc_nr_pages(void);
#else
static inline void vmalloc_init(void)
{
}
static inline unsigned long vmalloc_nr_pages(void) { return 0; }
#endif

extern void *vmalloc(unsigned long size);
extern void *vzalloc(unsigned long size);
extern void *vmalloc_user(unsigned long size);
extern void *vmalloc_node(unsigned long size, int node);
extern void *vzalloc_node(unsigned long size, int node);
extern void *vmalloc_user_node_flags(unsigned long size, int node, gfp_t flags);
extern void *vmalloc_exec(unsigned long size);
extern void *vmalloc_32(unsigned long size);
extern void *vmalloc_32_user(unsigned long size);
extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
			unsigned long start, unsigned long end, gfp_t gfp_mask,
			pgprot_t prot, unsigned long vm_flags, int node,
			const void *caller);
#ifndef CONFIG_MMU
extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags);
static inline void *__vmalloc_node_flags_caller(unsigned long size, int node,
						gfp_t flags, void *caller)
{
	return __vmalloc_node_flags(size, node, flags);
}
#else
extern void *__vmalloc_node_flags_caller(unsigned long size,
					 int node, gfp_t flags, void *caller);
#endif

extern void vfree(const void *addr);
extern void vfree_atomic(const void *addr);

extern void *vmap(struct page **pages, unsigned int count,
			unsigned long flags, pgprot_t prot);
extern void vunmap(const void *addr);

extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
				       unsigned long uaddr, void *kaddr,
				       unsigned long size);

extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
							unsigned long pgoff);
void vmalloc_sync_mappings(void);
void vmalloc_sync_unmappings(void);

/*
 *	Lowlevel-APIs (not for driver use!)
 */

static inline size_t get_vm_area_size(const struct vm_struct *area)
{
	if (!(area->flags & VM_NO_GUARD))
		/* return actual size without guard page */
		return area->size - PAGE_SIZE;
	else
		return area->size;

}

extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
extern struct vm_struct *get_vm_area_caller(unsigned long size,
					unsigned long flags, const void *caller);
extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
					unsigned long start, unsigned long end);
extern struct vm_struct *__get_vm_area_caller(unsigned long size,
					unsigned long flags,
					unsigned long start, unsigned long end,
					const void *caller);
extern struct vm_struct *remove_vm_area(const void *addr);
extern struct vm_struct *find_vm_area(const void *addr);

extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
			struct page **pages);
#ifdef CONFIG_MMU
extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
				    pgprot_t prot, struct page **pages);
extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
extern void unmap_kernel_range(unsigned long addr, unsigned long size);
static inline void set_vm_flush_reset_perms(void *addr)
{
	struct vm_struct *vm = find_vm_area(addr);

	if (vm)
		vm->flags |= VM_FLUSH_RESET_PERMS;
}
#else
static inline int
map_kernel_range_noflush(unsigned long start, unsigned long size,
			pgprot_t prot, struct page **pages)
{
	return size >> PAGE_SHIFT;
}
static inline void
unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
{
}
static inline void
unmap_kernel_range(unsigned long addr, unsigned long size)
{
}
static inline void set_vm_flush_reset_perms(void *addr)
{
}
#endif

/* Allocate/destroy a 'vmalloc' VM area. */
extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
extern void free_vm_area(struct vm_struct *area);

/* for /dev/kmem */
extern long vread(char *buf, char *addr, unsigned long count);
extern long vwrite(char *buf, char *addr, unsigned long count);

/*
 *	Internals.  Dont't use..
 */
extern struct list_head vmap_area_list;
extern __init void vm_area_add_early(struct vm_struct *vm);
extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);

#ifdef CONFIG_SMP
# ifdef CONFIG_MMU
struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
				     const size_t *sizes, int nr_vms,
				     size_t align);

void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
# else
static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long *offsets,
		const size_t *sizes, int nr_vms,
		size_t align)
{
	return NULL;
}

static inline void
pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
{
}
# endif
#endif

#ifdef CONFIG_MMU
#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
#else
#define VMALLOC_TOTAL 0UL
#endif

int register_vmap_purge_notifier(struct notifier_block *nb);
int unregister_vmap_purge_notifier(struct notifier_block *nb);

#endif /* _LINUX_VMALLOC_H */