xref: /linux-6.15/include/linux/vmalloc.h (revision b6714911)
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_ALLOW_HUGE_VMAP	0x00000400      /* Allow for huge pages on archs with HAVE_ARCH_HUGE_VMALLOC */
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 /* bits [20..32] reserved for arch specific ioremap internals */
39 
40 /*
41  * Maximum alignment for ioremap() regions.
42  * Can be overridden by arch-specific value.
43  */
44 #ifndef IOREMAP_MAX_ORDER
45 #define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
46 #endif
47 
48 struct vm_struct {
49 	struct vm_struct	*next;
50 	void			*addr;
51 	unsigned long		size;
52 	unsigned long		flags;
53 	struct page		**pages;
54 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
55 	unsigned int		page_order;
56 #endif
57 	unsigned int		nr_pages;
58 	phys_addr_t		phys_addr;
59 	const void		*caller;
60 };
61 
62 struct 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 free_vmap_area_root)
73 	 *    2) or "busy" tree (root is 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 	unsigned long flags; /* mark type of vm_map_ram area */
80 };
81 
82 /* archs that select HAVE_ARCH_HUGE_VMAP should override one or more of these */
83 #ifndef arch_vmap_p4d_supported
84 static inline bool arch_vmap_p4d_supported(pgprot_t prot)
85 {
86 	return false;
87 }
88 #endif
89 
90 #ifndef arch_vmap_pud_supported
91 static inline bool arch_vmap_pud_supported(pgprot_t prot)
92 {
93 	return false;
94 }
95 #endif
96 
97 #ifndef arch_vmap_pmd_supported
98 static inline bool arch_vmap_pmd_supported(pgprot_t prot)
99 {
100 	return false;
101 }
102 #endif
103 
104 #ifndef arch_vmap_pte_range_map_size
105 static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, unsigned long end,
106 							 u64 pfn, unsigned int max_page_shift)
107 {
108 	return PAGE_SIZE;
109 }
110 #endif
111 
112 #ifndef arch_vmap_pte_supported_shift
113 static inline int arch_vmap_pte_supported_shift(unsigned long size)
114 {
115 	return PAGE_SHIFT;
116 }
117 #endif
118 
119 #ifndef arch_vmap_pgprot_tagged
120 static inline pgprot_t arch_vmap_pgprot_tagged(pgprot_t prot)
121 {
122 	return prot;
123 }
124 #endif
125 
126 /*
127  *	Highlevel APIs for driver use
128  */
129 extern void vm_unmap_ram(const void *mem, unsigned int count);
130 extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
131 extern void vm_unmap_aliases(void);
132 
133 #ifdef CONFIG_MMU
134 extern unsigned long vmalloc_nr_pages(void);
135 #else
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_huge(unsigned long size, gfp_t gfp_mask) __alloc_size(1);
154 
155 extern void *__vmalloc_array(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);
156 extern void *vmalloc_array(size_t n, size_t size) __alloc_size(1, 2);
157 extern void *__vcalloc(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);
158 extern void *vcalloc(size_t n, size_t size) __alloc_size(1, 2);
159 
160 extern void vfree(const void *addr);
161 extern void vfree_atomic(const void *addr);
162 
163 extern void *vmap(struct page **pages, unsigned int count,
164 			unsigned long flags, pgprot_t prot);
165 void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
166 extern void vunmap(const void *addr);
167 
168 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
169 				       unsigned long uaddr, void *kaddr,
170 				       unsigned long pgoff, unsigned long size);
171 
172 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
173 							unsigned long pgoff);
174 
175 /*
176  * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
177  * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
178  * needs to be called.
179  */
180 #ifndef ARCH_PAGE_TABLE_SYNC_MASK
181 #define ARCH_PAGE_TABLE_SYNC_MASK 0
182 #endif
183 
184 /*
185  * There is no default implementation for arch_sync_kernel_mappings(). It is
186  * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
187  * is 0.
188  */
189 void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
190 
191 /*
192  *	Lowlevel-APIs (not for driver use!)
193  */
194 
195 static inline size_t get_vm_area_size(const struct vm_struct *area)
196 {
197 	if (!(area->flags & VM_NO_GUARD))
198 		/* return actual size without guard page */
199 		return area->size - PAGE_SIZE;
200 	else
201 		return area->size;
202 
203 }
204 
205 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
206 extern struct vm_struct *get_vm_area_caller(unsigned long size,
207 					unsigned long flags, const void *caller);
208 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
209 					unsigned long flags,
210 					unsigned long start, unsigned long end,
211 					const void *caller);
212 void free_vm_area(struct vm_struct *area);
213 extern struct vm_struct *remove_vm_area(const void *addr);
214 extern struct vm_struct *find_vm_area(const void *addr);
215 struct vmap_area *find_vmap_area(unsigned long addr);
216 
217 static inline bool is_vm_area_hugepages(const void *addr)
218 {
219 	/*
220 	 * This may not 100% tell if the area is mapped with > PAGE_SIZE
221 	 * page table entries, if for some reason the architecture indicates
222 	 * larger sizes are available but decides not to use them, nothing
223 	 * prevents that. This only indicates the size of the physical page
224 	 * allocated in the vmalloc layer.
225 	 */
226 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
227 	return find_vm_area(addr)->page_order > 0;
228 #else
229 	return false;
230 #endif
231 }
232 
233 #ifdef CONFIG_MMU
234 void vunmap_range(unsigned long addr, unsigned long end);
235 static inline void set_vm_flush_reset_perms(void *addr)
236 {
237 	struct vm_struct *vm = find_vm_area(addr);
238 
239 	if (vm)
240 		vm->flags |= VM_FLUSH_RESET_PERMS;
241 }
242 
243 #else
244 static inline void set_vm_flush_reset_perms(void *addr)
245 {
246 }
247 #endif
248 
249 /* for /proc/kcore */
250 extern long vread(char *buf, char *addr, unsigned long count);
251 
252 /*
253  *	Internals.  Don't use..
254  */
255 extern struct list_head vmap_area_list;
256 extern __init void vm_area_add_early(struct vm_struct *vm);
257 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
258 
259 #ifdef CONFIG_SMP
260 # ifdef CONFIG_MMU
261 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
262 				     const size_t *sizes, int nr_vms,
263 				     size_t align);
264 
265 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
266 # else
267 static inline struct vm_struct **
268 pcpu_get_vm_areas(const unsigned long *offsets,
269 		const size_t *sizes, int nr_vms,
270 		size_t align)
271 {
272 	return NULL;
273 }
274 
275 static inline void
276 pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
277 {
278 }
279 # endif
280 #endif
281 
282 #ifdef CONFIG_MMU
283 #define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
284 #else
285 #define VMALLOC_TOTAL 0UL
286 #endif
287 
288 int register_vmap_purge_notifier(struct notifier_block *nb);
289 int unregister_vmap_purge_notifier(struct notifier_block *nb);
290 
291 #if defined(CONFIG_MMU) && defined(CONFIG_PRINTK)
292 bool vmalloc_dump_obj(void *object);
293 #else
294 static inline bool vmalloc_dump_obj(void *object) { return false; }
295 #endif
296 
297 #endif /* _LINUX_VMALLOC_H */
298