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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
15struct vm_area_struct; /* vma defining user mapping in mm_types.h */
16struct 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
28/*
29 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
30 *
31 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
32 * shadow memory has been mapped. It's used to handle allocation errors so that
33 * we don't try to poision shadow on free if it was never allocated.
34 *
35 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
36 * determine which allocations need the module shadow freed.
37 */
38
39/*
40 * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
41 * vfree_atomic().
42 */
43#define VM_FLUSH_RESET_PERMS 0x00000100 /* Reset direct map and flush TLB on unmap */
44
45/* bits [20..32] reserved for arch specific ioremap internals */
46
47/*
48 * Maximum alignment for ioremap() regions.
49 * Can be overriden by arch-specific value.
50 */
51#ifndef IOREMAP_MAX_ORDER
52#define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
53#endif
54
55struct vm_struct {
56 struct vm_struct *next;
57 void *addr;
58 unsigned long size;
59 unsigned long flags;
60 struct page **pages;
61 unsigned int nr_pages;
62 phys_addr_t phys_addr;
63 const void *caller;
64};
65
66struct vmap_area {
67 unsigned long va_start;
68 unsigned long va_end;
69
70 struct rb_node rb_node; /* address sorted rbtree */
71 struct list_head list; /* address sorted list */
72
73 /*
74 * The following three variables can be packed, because
75 * a vmap_area object is always one of the three states:
76 * 1) in "free" tree (root is vmap_area_root)
77 * 2) in "busy" tree (root is free_vmap_area_root)
78 * 3) in purge list (head is vmap_purge_list)
79 */
80 union {
81 unsigned long subtree_max_size; /* in "free" tree */
82 struct vm_struct *vm; /* in "busy" tree */
83 struct llist_node purge_list; /* in purge list */
84 };
85};
86
87/*
88 * Highlevel APIs for driver use
89 */
90extern void vm_unmap_ram(const void *mem, unsigned int count);
91extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
92extern void vm_unmap_aliases(void);
93
94#ifdef CONFIG_MMU
95extern void __init vmalloc_init(void);
96extern unsigned long vmalloc_nr_pages(void);
97#else
98static inline void vmalloc_init(void)
99{
100}
101static inline unsigned long vmalloc_nr_pages(void) { return 0; }
102#endif
103
104extern void *vmalloc(unsigned long size);
105extern void *vzalloc(unsigned long size);
106extern void *vmalloc_user(unsigned long size);
107extern void *vmalloc_node(unsigned long size, int node);
108extern void *vzalloc_node(unsigned long size, int node);
109extern void *vmalloc_32(unsigned long size);
110extern void *vmalloc_32_user(unsigned long size);
111extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
112extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
113 unsigned long start, unsigned long end, gfp_t gfp_mask,
114 pgprot_t prot, unsigned long vm_flags, int node,
115 const void *caller);
116void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
117 int node, const void *caller);
118
119extern void vfree(const void *addr);
120extern void vfree_atomic(const void *addr);
121
122extern void *vmap(struct page **pages, unsigned int count,
123 unsigned long flags, pgprot_t prot);
124extern void vunmap(const void *addr);
125
126extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
127 unsigned long uaddr, void *kaddr,
128 unsigned long pgoff, unsigned long size);
129
130extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
131 unsigned long pgoff);
132
133/*
134 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
135 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
136 * needs to be called.
137 */
138#ifndef ARCH_PAGE_TABLE_SYNC_MASK
139#define ARCH_PAGE_TABLE_SYNC_MASK 0
140#endif
141
142/*
143 * There is no default implementation for arch_sync_kernel_mappings(). It is
144 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
145 * is 0.
146 */
147void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
148
149/*
150 * Lowlevel-APIs (not for driver use!)
151 */
152
153static inline size_t get_vm_area_size(const struct vm_struct *area)
154{
155 if (!(area->flags & VM_NO_GUARD))
156 /* return actual size without guard page */
157 return area->size - PAGE_SIZE;
158 else
159 return area->size;
160
161}
162
163extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
164extern struct vm_struct *get_vm_area_caller(unsigned long size,
165 unsigned long flags, const void *caller);
166extern struct vm_struct *__get_vm_area_caller(unsigned long size,
167 unsigned long flags,
168 unsigned long start, unsigned long end,
169 const void *caller);
170extern struct vm_struct *remove_vm_area(const void *addr);
171extern struct vm_struct *find_vm_area(const void *addr);
172
173#ifdef CONFIG_MMU
174extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
175 pgprot_t prot, struct page **pages);
176int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
177 struct page **pages);
178extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
179extern void unmap_kernel_range(unsigned long addr, unsigned long size);
180static inline void set_vm_flush_reset_perms(void *addr)
181{
182 struct vm_struct *vm = find_vm_area(addr);
183
184 if (vm)
185 vm->flags |= VM_FLUSH_RESET_PERMS;
186}
187#else
188static inline int
189map_kernel_range_noflush(unsigned long start, unsigned long size,
190 pgprot_t prot, struct page **pages)
191{
192 return size >> PAGE_SHIFT;
193}
194#define map_kernel_range map_kernel_range_noflush
195static inline void
196unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
197{
198}
199#define unmap_kernel_range unmap_kernel_range_noflush
200static inline void set_vm_flush_reset_perms(void *addr)
201{
202}
203#endif
204
205/* Allocate/destroy a 'vmalloc' VM area. */
206extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
207extern void free_vm_area(struct vm_struct *area);
208
209/* for /dev/kmem */
210extern long vread(char *buf, char *addr, unsigned long count);
211extern long vwrite(char *buf, char *addr, unsigned long count);
212
213/*
214 * Internals. Dont't use..
215 */
216extern struct list_head vmap_area_list;
217extern __init void vm_area_add_early(struct vm_struct *vm);
218extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
219
220#ifdef CONFIG_SMP
221# ifdef CONFIG_MMU
222struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
223 const size_t *sizes, int nr_vms,
224 size_t align);
225
226void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
227# else
228static inline struct vm_struct **
229pcpu_get_vm_areas(const unsigned long *offsets,
230 const size_t *sizes, int nr_vms,
231 size_t align)
232{
233 return NULL;
234}
235
236static inline void
237pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
238{
239}
240# endif
241#endif
242
243#ifdef CONFIG_MMU
244#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
245#else
246#define VMALLOC_TOTAL 0UL
247#endif
248
249int register_vmap_purge_notifier(struct notifier_block *nb);
250int unregister_vmap_purge_notifier(struct notifier_block *nb);
251
252#endif /* _LINUX_VMALLOC_H */