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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 /* ***DANGEROUS*** 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#define VM_NO_HUGE_VMAP 0x00000400 /* force PAGE_SIZE pte mapping */
30
31#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
32 !defined(CONFIG_KASAN_VMALLOC)
33#define VM_DEFER_KMEMLEAK 0x00000800 /* defer kmemleak object creation */
34#else
35#define VM_DEFER_KMEMLEAK 0
36#endif
37
38/*
39 * VM_KASAN is used slightly differently depending on CONFIG_KASAN_VMALLOC.
40 *
41 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
42 * shadow memory has been mapped. It's used to handle allocation errors so that
43 * we don't try to poison shadow on free if it was never allocated.
44 *
45 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
46 * determine which allocations need the module shadow freed.
47 */
48
49/* bits [20..32] reserved for arch specific ioremap internals */
50
51/*
52 * Maximum alignment for ioremap() regions.
53 * Can be overridden by arch-specific value.
54 */
55#ifndef IOREMAP_MAX_ORDER
56#define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
57#endif
58
59struct vm_struct {
60 struct vm_struct *next;
61 void *addr;
62 unsigned long size;
63 unsigned long flags;
64 struct page **pages;
65#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
66 unsigned int page_order;
67#endif
68 unsigned int nr_pages;
69 phys_addr_t phys_addr;
70 const void *caller;
71};
72
73struct vmap_area {
74 unsigned long va_start;
75 unsigned long va_end;
76
77 struct rb_node rb_node; /* address sorted rbtree */
78 struct list_head list; /* address sorted list */
79
80 /*
81 * The following two variables can be packed, because
82 * a vmap_area object can be either:
83 * 1) in "free" tree (root is vmap_area_root)
84 * 2) or "busy" tree (root is free_vmap_area_root)
85 */
86 union {
87 unsigned long subtree_max_size; /* in "free" tree */
88 struct vm_struct *vm; /* in "busy" tree */
89 };
90};
91
92/* archs that select HAVE_ARCH_HUGE_VMAP should override one or more of these */
93#ifndef arch_vmap_p4d_supported
94static inline bool arch_vmap_p4d_supported(pgprot_t prot)
95{
96 return false;
97}
98#endif
99
100#ifndef arch_vmap_pud_supported
101static inline bool arch_vmap_pud_supported(pgprot_t prot)
102{
103 return false;
104}
105#endif
106
107#ifndef arch_vmap_pmd_supported
108static inline bool arch_vmap_pmd_supported(pgprot_t prot)
109{
110 return false;
111}
112#endif
113
114#ifndef arch_vmap_pte_range_map_size
115static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, unsigned long end,
116 u64 pfn, unsigned int max_page_shift)
117{
118 return PAGE_SIZE;
119}
120#endif
121
122#ifndef arch_vmap_pte_supported_shift
123static inline int arch_vmap_pte_supported_shift(unsigned long size)
124{
125 return PAGE_SHIFT;
126}
127#endif
128
129/*
130 * Highlevel APIs for driver use
131 */
132extern void vm_unmap_ram(const void *mem, unsigned int count);
133extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
134extern void vm_unmap_aliases(void);
135
136#ifdef CONFIG_MMU
137extern void __init vmalloc_init(void);
138extern unsigned long vmalloc_nr_pages(void);
139#else
140static inline void vmalloc_init(void)
141{
142}
143static inline unsigned long vmalloc_nr_pages(void) { return 0; }
144#endif
145
146extern void *vmalloc(unsigned long size) __alloc_size(1);
147extern void *vzalloc(unsigned long size) __alloc_size(1);
148extern void *vmalloc_user(unsigned long size) __alloc_size(1);
149extern void *vmalloc_node(unsigned long size, int node) __alloc_size(1);
150extern void *vzalloc_node(unsigned long size, int node) __alloc_size(1);
151extern void *vmalloc_32(unsigned long size) __alloc_size(1);
152extern void *vmalloc_32_user(unsigned long size) __alloc_size(1);
153extern void *__vmalloc(unsigned long size, gfp_t gfp_mask) __alloc_size(1);
154extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
155 unsigned long start, unsigned long end, gfp_t gfp_mask,
156 pgprot_t prot, unsigned long vm_flags, int node,
157 const void *caller) __alloc_size(1);
158void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
159 int node, const void *caller) __alloc_size(1);
160void *vmalloc_no_huge(unsigned long size) __alloc_size(1);
161
162extern void vfree(const void *addr);
163extern void vfree_atomic(const void *addr);
164
165extern void *vmap(struct page **pages, unsigned int count,
166 unsigned long flags, pgprot_t prot);
167void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
168extern void vunmap(const void *addr);
169
170extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
171 unsigned long uaddr, void *kaddr,
172 unsigned long pgoff, unsigned long size);
173
174extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
175 unsigned long pgoff);
176
177/*
178 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
179 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
180 * needs to be called.
181 */
182#ifndef ARCH_PAGE_TABLE_SYNC_MASK
183#define ARCH_PAGE_TABLE_SYNC_MASK 0
184#endif
185
186/*
187 * There is no default implementation for arch_sync_kernel_mappings(). It is
188 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
189 * is 0.
190 */
191void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
192
193/*
194 * Lowlevel-APIs (not for driver use!)
195 */
196
197static inline size_t get_vm_area_size(const struct vm_struct *area)
198{
199 if (!(area->flags & VM_NO_GUARD))
200 /* return actual size without guard page */
201 return area->size - PAGE_SIZE;
202 else
203 return area->size;
204
205}
206
207extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
208extern struct vm_struct *get_vm_area_caller(unsigned long size,
209 unsigned long flags, const void *caller);
210extern struct vm_struct *__get_vm_area_caller(unsigned long size,
211 unsigned long flags,
212 unsigned long start, unsigned long end,
213 const void *caller);
214void free_vm_area(struct vm_struct *area);
215extern struct vm_struct *remove_vm_area(const void *addr);
216extern struct vm_struct *find_vm_area(const void *addr);
217
218static inline bool is_vm_area_hugepages(const void *addr)
219{
220 /*
221 * This may not 100% tell if the area is mapped with > PAGE_SIZE
222 * page table entries, if for some reason the architecture indicates
223 * larger sizes are available but decides not to use them, nothing
224 * prevents that. This only indicates the size of the physical page
225 * allocated in the vmalloc layer.
226 */
227#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
228 return find_vm_area(addr)->page_order > 0;
229#else
230 return false;
231#endif
232}
233
234#ifdef CONFIG_MMU
235void vunmap_range(unsigned long addr, unsigned long end);
236static inline void set_vm_flush_reset_perms(void *addr)
237{
238 struct vm_struct *vm = find_vm_area(addr);
239
240 if (vm)
241 vm->flags |= VM_FLUSH_RESET_PERMS;
242}
243
244#else
245static inline void set_vm_flush_reset_perms(void *addr)
246{
247}
248#endif
249
250/* for /proc/kcore */
251extern long vread(char *buf, char *addr, unsigned long count);
252
253/*
254 * Internals. Don't use..
255 */
256extern struct list_head vmap_area_list;
257extern __init void vm_area_add_early(struct vm_struct *vm);
258extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
259
260#ifdef CONFIG_SMP
261# ifdef CONFIG_MMU
262struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
263 const size_t *sizes, int nr_vms,
264 size_t align);
265
266void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
267# else
268static inline struct vm_struct **
269pcpu_get_vm_areas(const unsigned long *offsets,
270 const size_t *sizes, int nr_vms,
271 size_t align)
272{
273 return NULL;
274}
275
276static inline void
277pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
278{
279}
280# endif
281#endif
282
283#ifdef CONFIG_MMU
284#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
285#else
286#define VMALLOC_TOTAL 0UL
287#endif
288
289int register_vmap_purge_notifier(struct notifier_block *nb);
290int unregister_vmap_purge_notifier(struct notifier_block *nb);
291
292#if defined(CONFIG_MMU) && defined(CONFIG_PRINTK)
293bool vmalloc_dump_obj(void *object);
294#else
295static inline bool vmalloc_dump_obj(void *object) { return false; }
296#endif
297
298#endif /* _LINUX_VMALLOC_H */