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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#define VM_FLUSH_RESET_PERMS 0x00000100 /* reset direct map and flush TLB on unmap, can't be freed in atomic context */
28#define VM_MAP_PUT_PAGES 0x00000200 /* put pages and free array in vfree */
29
30/*
31 * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
32 *
33 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
34 * shadow memory has been mapped. It's used to handle allocation errors so that
35 * we don't try to poision shadow on free if it was never allocated.
36 *
37 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
38 * determine which allocations need the module shadow freed.
39 */
40
41/* bits [20..32] reserved for arch specific ioremap internals */
42
43/*
44 * Maximum alignment for ioremap() regions.
45 * Can be overriden by arch-specific value.
46 */
47#ifndef IOREMAP_MAX_ORDER
48#define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
49#endif
50
51struct vm_struct {
52 struct vm_struct *next;
53 void *addr;
54 unsigned long size;
55 unsigned long flags;
56 struct page **pages;
57 unsigned int nr_pages;
58 phys_addr_t phys_addr;
59 const void *caller;
60};
61
62struct vmap_area {
63 unsigned long va_start;
64 unsigned long va_end;
65
66 struct rb_node rb_node; /* address sorted rbtree */
67 struct list_head list; /* address sorted list */
68
69 /*
70 * The following two variables can be packed, because
71 * a vmap_area object can be either:
72 * 1) in "free" tree (root is vmap_area_root)
73 * 2) or "busy" tree (root is free_vmap_area_root)
74 */
75 union {
76 unsigned long subtree_max_size; /* in "free" tree */
77 struct vm_struct *vm; /* in "busy" tree */
78 };
79};
80
81/*
82 * Highlevel APIs for driver use
83 */
84extern void vm_unmap_ram(const void *mem, unsigned int count);
85extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
86extern void vm_unmap_aliases(void);
87
88#ifdef CONFIG_MMU
89extern void __init vmalloc_init(void);
90extern unsigned long vmalloc_nr_pages(void);
91#else
92static inline void vmalloc_init(void)
93{
94}
95static inline unsigned long vmalloc_nr_pages(void) { return 0; }
96#endif
97
98extern void *vmalloc(unsigned long size);
99extern void *vzalloc(unsigned long size);
100extern void *vmalloc_user(unsigned long size);
101extern void *vmalloc_node(unsigned long size, int node);
102extern void *vzalloc_node(unsigned long size, int node);
103extern void *vmalloc_32(unsigned long size);
104extern void *vmalloc_32_user(unsigned long size);
105extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
106extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
107 unsigned long start, unsigned long end, gfp_t gfp_mask,
108 pgprot_t prot, unsigned long vm_flags, int node,
109 const void *caller);
110void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
111 int node, const void *caller);
112
113extern void vfree(const void *addr);
114extern void vfree_atomic(const void *addr);
115
116extern void *vmap(struct page **pages, unsigned int count,
117 unsigned long flags, pgprot_t prot);
118void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
119extern void vunmap(const void *addr);
120
121extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
122 unsigned long uaddr, void *kaddr,
123 unsigned long pgoff, unsigned long size);
124
125extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
126 unsigned long pgoff);
127
128/*
129 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
130 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
131 * needs to be called.
132 */
133#ifndef ARCH_PAGE_TABLE_SYNC_MASK
134#define ARCH_PAGE_TABLE_SYNC_MASK 0
135#endif
136
137/*
138 * There is no default implementation for arch_sync_kernel_mappings(). It is
139 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
140 * is 0.
141 */
142void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
143
144/*
145 * Lowlevel-APIs (not for driver use!)
146 */
147
148static inline size_t get_vm_area_size(const struct vm_struct *area)
149{
150 if (!(area->flags & VM_NO_GUARD))
151 /* return actual size without guard page */
152 return area->size - PAGE_SIZE;
153 else
154 return area->size;
155
156}
157
158extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
159extern struct vm_struct *get_vm_area_caller(unsigned long size,
160 unsigned long flags, const void *caller);
161extern struct vm_struct *__get_vm_area_caller(unsigned long size,
162 unsigned long flags,
163 unsigned long start, unsigned long end,
164 const void *caller);
165void free_vm_area(struct vm_struct *area);
166extern struct vm_struct *remove_vm_area(const void *addr);
167extern struct vm_struct *find_vm_area(const void *addr);
168
169#ifdef CONFIG_MMU
170extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
171 pgprot_t prot, struct page **pages);
172int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
173 struct page **pages);
174extern void unmap_kernel_range_noflush(unsigned long addr, unsigned long size);
175extern void unmap_kernel_range(unsigned long addr, unsigned long size);
176static inline void set_vm_flush_reset_perms(void *addr)
177{
178 struct vm_struct *vm = find_vm_area(addr);
179
180 if (vm)
181 vm->flags |= VM_FLUSH_RESET_PERMS;
182}
183#else
184static inline int
185map_kernel_range_noflush(unsigned long start, unsigned long size,
186 pgprot_t prot, struct page **pages)
187{
188 return size >> PAGE_SHIFT;
189}
190#define map_kernel_range map_kernel_range_noflush
191static inline void
192unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
193{
194}
195#define unmap_kernel_range unmap_kernel_range_noflush
196static inline void set_vm_flush_reset_perms(void *addr)
197{
198}
199#endif
200
201/* for /dev/kmem */
202extern long vread(char *buf, char *addr, unsigned long count);
203extern long vwrite(char *buf, char *addr, unsigned long count);
204
205/*
206 * Internals. Dont't use..
207 */
208extern struct list_head vmap_area_list;
209extern __init void vm_area_add_early(struct vm_struct *vm);
210extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
211
212#ifdef CONFIG_SMP
213# ifdef CONFIG_MMU
214struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
215 const size_t *sizes, int nr_vms,
216 size_t align);
217
218void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
219# else
220static inline struct vm_struct **
221pcpu_get_vm_areas(const unsigned long *offsets,
222 const size_t *sizes, int nr_vms,
223 size_t align)
224{
225 return NULL;
226}
227
228static inline void
229pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
230{
231}
232# endif
233#endif
234
235#ifdef CONFIG_MMU
236#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
237#else
238#define VMALLOC_TOTAL 0UL
239#endif
240
241int register_vmap_purge_notifier(struct notifier_block *nb);
242int unregister_vmap_purge_notifier(struct notifier_block *nb);
243
244#endif /* _LINUX_VMALLOC_H */