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 struct iov_iter;		/* in uio.h */
18 
19 /* bits in flags of vmalloc's vm_struct below */
20 #define VM_IOREMAP		0x00000001	/* ioremap() and friends */
21 #define VM_ALLOC		0x00000002	/* vmalloc() */
22 #define VM_MAP			0x00000004	/* vmap()ed pages */
23 #define VM_USERMAP		0x00000008	/* suitable for remap_vmalloc_range */
24 #define VM_DMA_COHERENT		0x00000010	/* dma_alloc_coherent */
25 #define VM_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
26 #define VM_NO_GUARD		0x00000040      /* ***DANGEROUS*** don't add guard page */
27 #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
28 #define VM_FLUSH_RESET_PERMS	0x00000100	/* reset direct map and flush TLB on unmap, can't be freed in atomic context */
29 #define VM_MAP_PUT_PAGES	0x00000200	/* put pages and free array in vfree */
30 #define VM_ALLOW_HUGE_VMAP	0x00000400      /* Allow for huge pages on archs with HAVE_ARCH_HUGE_VMALLOC */
31 
32 #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
33 	!defined(CONFIG_KASAN_VMALLOC)
34 #define VM_DEFER_KMEMLEAK	0x00000800	/* defer kmemleak object creation */
35 #else
36 #define VM_DEFER_KMEMLEAK	0
37 #endif
38 
39 /* bits [20..32] reserved for arch specific ioremap internals */
40 
41 /*
42  * Maximum alignment for ioremap() regions.
43  * Can be overridden by arch-specific value.
44  */
45 #ifndef IOREMAP_MAX_ORDER
46 #define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
47 #endif
48 
49 struct vm_struct {
50 	struct vm_struct	*next;
51 	void			*addr;
52 	unsigned long		size;
53 	unsigned long		flags;
54 	struct page		**pages;
55 #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
56 	unsigned int		page_order;
57 #endif
58 	unsigned int		nr_pages;
59 	phys_addr_t		phys_addr;
60 	const void		*caller;
61 };
62 
63 struct vmap_area {
64 	unsigned long va_start;
65 	unsigned long va_end;
66 
67 	struct rb_node rb_node;         /* address sorted rbtree */
68 	struct list_head list;          /* address sorted list */
69 
70 	/*
71 	 * The following two variables can be packed, because
72 	 * a vmap_area object can be either:
73 	 *    1) in "free" tree (root is free_vmap_area_root)
74 	 *    2) or "busy" tree (root is vmap_area_root)
75 	 */
76 	union {
77 		unsigned long subtree_max_size; /* in "free" tree */
78 		struct vm_struct *vm;           /* in "busy" tree */
79 	};
80 	unsigned long flags; /* mark type of vm_map_ram area */
81 };
82 
83 /* archs that select HAVE_ARCH_HUGE_VMAP should override one or more of these */
84 #ifndef arch_vmap_p4d_supported
arch_vmap_p4d_supported(pgprot_t prot)85 static inline bool arch_vmap_p4d_supported(pgprot_t prot)
86 {
87 	return false;
88 }
89 #endif
90 
91 #ifndef arch_vmap_pud_supported
arch_vmap_pud_supported(pgprot_t prot)92 static inline bool arch_vmap_pud_supported(pgprot_t prot)
93 {
94 	return false;
95 }
96 #endif
97 
98 #ifndef arch_vmap_pmd_supported
arch_vmap_pmd_supported(pgprot_t prot)99 static inline bool arch_vmap_pmd_supported(pgprot_t prot)
100 {
101 	return false;
102 }
103 #endif
104 
105 #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)106 static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, unsigned long end,
107 							 u64 pfn, unsigned int max_page_shift)
108 {
109 	return PAGE_SIZE;
110 }
111 #endif
112 
113 #ifndef arch_vmap_pte_supported_shift
arch_vmap_pte_supported_shift(unsigned long size)114 static inline int arch_vmap_pte_supported_shift(unsigned long size)
115 {
116 	return PAGE_SHIFT;
117 }
118 #endif
119 
120 #ifndef arch_vmap_pgprot_tagged
arch_vmap_pgprot_tagged(pgprot_t prot)121 static inline pgprot_t arch_vmap_pgprot_tagged(pgprot_t prot)
122 {
123 	return prot;
124 }
125 #endif
126 
127 /*
128  *	Highlevel APIs for driver use
129  */
130 extern void vm_unmap_ram(const void *mem, unsigned int count);
131 extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
132 extern void vm_unmap_aliases(void);
133 
134 #ifdef CONFIG_MMU
135 extern unsigned long vmalloc_nr_pages(void);
136 #else
vmalloc_nr_pages(void)137 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
138 #endif
139 
140 extern void *vmalloc(unsigned long size) __alloc_size(1);
141 extern void *vzalloc(unsigned long size) __alloc_size(1);
142 extern void *vmalloc_user(unsigned long size) __alloc_size(1);
143 extern void *vmalloc_node(unsigned long size, int node) __alloc_size(1);
144 extern void *vzalloc_node(unsigned long size, int node) __alloc_size(1);
145 extern void *vmalloc_32(unsigned long size) __alloc_size(1);
146 extern void *vmalloc_32_user(unsigned long size) __alloc_size(1);
147 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask) __alloc_size(1);
148 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
149 			unsigned long start, unsigned long end, gfp_t gfp_mask,
150 			pgprot_t prot, unsigned long vm_flags, int node,
151 			const void *caller) __alloc_size(1);
152 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
153 		int node, const void *caller) __alloc_size(1);
154 void *vmalloc_huge(unsigned long size, gfp_t gfp_mask) __alloc_size(1);
155 
156 extern void *__vmalloc_array(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);
157 extern void *vmalloc_array(size_t n, size_t size) __alloc_size(1, 2);
158 extern void *__vcalloc(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);
159 extern void *vcalloc(size_t n, size_t size) __alloc_size(1, 2);
160 
161 extern void vfree(const void *addr);
162 extern void vfree_atomic(const void *addr);
163 
164 extern void *vmap(struct page **pages, unsigned int count,
165 			unsigned long flags, pgprot_t prot);
166 void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
167 extern void vunmap(const void *addr);
168 
169 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
170 				       unsigned long uaddr, void *kaddr,
171 				       unsigned long pgoff, unsigned long size);
172 
173 extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
174 							unsigned long pgoff);
175 
176 /*
177  * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
178  * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
179  * needs to be called.
180  */
181 #ifndef ARCH_PAGE_TABLE_SYNC_MASK
182 #define ARCH_PAGE_TABLE_SYNC_MASK 0
183 #endif
184 
185 /*
186  * There is no default implementation for arch_sync_kernel_mappings(). It is
187  * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
188  * is 0.
189  */
190 void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
191 
192 /*
193  *	Lowlevel-APIs (not for driver use!)
194  */
195 
get_vm_area_size(const struct vm_struct * area)196 static inline size_t get_vm_area_size(const struct vm_struct *area)
197 {
198 	if (!(area->flags & VM_NO_GUARD))
199 		/* return actual size without guard page */
200 		return area->size - PAGE_SIZE;
201 	else
202 		return area->size;
203 
204 }
205 
206 extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
207 extern struct vm_struct *get_vm_area_caller(unsigned long size,
208 					unsigned long flags, const void *caller);
209 extern struct vm_struct *__get_vm_area_caller(unsigned long size,
210 					unsigned long flags,
211 					unsigned long start, unsigned long end,
212 					const void *caller);
213 void free_vm_area(struct vm_struct *area);
214 extern struct vm_struct *remove_vm_area(const void *addr);
215 extern struct vm_struct *find_vm_area(const void *addr);
216 struct vmap_area *find_vmap_area(unsigned long addr);
217 
is_vm_area_hugepages(const void * addr)218 static 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
235 void vunmap_range(unsigned long addr, unsigned long end);
set_vm_flush_reset_perms(void * addr)236 static 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
set_vm_flush_reset_perms(void * addr)245 static inline void set_vm_flush_reset_perms(void *addr)
246 {
247 }
248 #endif
249 
250 /* for /proc/kcore */
251 extern long vread_iter(struct iov_iter *iter, const char *addr, size_t count);
252 
253 /*
254  *	Internals.  Don't use..
255  */
256 extern struct list_head vmap_area_list;
257 extern __init void vm_area_add_early(struct vm_struct *vm);
258 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
259 
260 #ifdef CONFIG_SMP
261 # ifdef CONFIG_MMU
262 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
263 				     const size_t *sizes, int nr_vms,
264 				     size_t align);
265 
266 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
267 # else
268 static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long * offsets,const size_t * sizes,int nr_vms,size_t align)269 pcpu_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 
276 static inline void
pcpu_free_vm_areas(struct vm_struct ** vms,int nr_vms)277 pcpu_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 
289 int register_vmap_purge_notifier(struct notifier_block *nb);
290 int unregister_vmap_purge_notifier(struct notifier_block *nb);
291 
292 #if defined(CONFIG_MMU) && defined(CONFIG_PRINTK)
293 bool vmalloc_dump_obj(void *object);
294 #else
vmalloc_dump_obj(void * object)295 static inline bool vmalloc_dump_obj(void *object) { return false; }
296 #endif
297 
298 #endif /* _LINUX_VMALLOC_H */
299