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