xref: /linux-6.15/include/linux/slab.h (revision 4f193362)
1 /*
2  * linux/mm/slab.h
3  * Written by Mark Hemment, 1996.
4  * ([email protected])
5  */
6 
7 #ifndef _LINUX_SLAB_H
8 #define	_LINUX_SLAB_H
9 
10 #if	defined(__KERNEL__)
11 
12 typedef struct kmem_cache kmem_cache_t;
13 
14 #include	<linux/config.h>	/* kmalloc_sizes.h needs CONFIG_ options */
15 #include	<linux/gfp.h>
16 #include	<linux/init.h>
17 #include	<linux/types.h>
18 #include	<asm/page.h>		/* kmalloc_sizes.h needs PAGE_SIZE */
19 #include	<asm/cache.h>		/* kmalloc_sizes.h needs L1_CACHE_BYTES */
20 
21 /* flags for kmem_cache_alloc() */
22 #define	SLAB_NOFS		GFP_NOFS
23 #define	SLAB_NOIO		GFP_NOIO
24 #define	SLAB_ATOMIC		GFP_ATOMIC
25 #define	SLAB_USER		GFP_USER
26 #define	SLAB_KERNEL		GFP_KERNEL
27 #define	SLAB_DMA		GFP_DMA
28 
29 #define SLAB_LEVEL_MASK		GFP_LEVEL_MASK
30 
31 #define	SLAB_NO_GROW		__GFP_NO_GROW	/* don't grow a cache */
32 
33 /* flags to pass to kmem_cache_create().
34  * The first 3 are only valid when the allocator as been build
35  * SLAB_DEBUG_SUPPORT.
36  */
37 #define	SLAB_DEBUG_FREE		0x00000100UL	/* Peform (expensive) checks on free */
38 #define	SLAB_DEBUG_INITIAL	0x00000200UL	/* Call constructor (as verifier) */
39 #define	SLAB_RED_ZONE		0x00000400UL	/* Red zone objs in a cache */
40 #define	SLAB_POISON		0x00000800UL	/* Poison objects */
41 #define	SLAB_NO_REAP		0x00001000UL	/* never reap from the cache */
42 #define	SLAB_HWCACHE_ALIGN	0x00002000UL	/* align objs on a h/w cache lines */
43 #define SLAB_CACHE_DMA		0x00004000UL	/* use GFP_DMA memory */
44 #define SLAB_MUST_HWCACHE_ALIGN	0x00008000UL	/* force alignment */
45 #define SLAB_STORE_USER		0x00010000UL	/* store the last owner for bug hunting */
46 #define SLAB_RECLAIM_ACCOUNT	0x00020000UL	/* track pages allocated to indicate
47 						   what is reclaimable later*/
48 #define SLAB_PANIC		0x00040000UL	/* panic if kmem_cache_create() fails */
49 #define SLAB_DESTROY_BY_RCU	0x00080000UL	/* defer freeing pages to RCU */
50 
51 /* flags passed to a constructor func */
52 #define	SLAB_CTOR_CONSTRUCTOR	0x001UL		/* if not set, then deconstructor */
53 #define SLAB_CTOR_ATOMIC	0x002UL		/* tell constructor it can't sleep */
54 #define	SLAB_CTOR_VERIFY	0x004UL		/* tell constructor it's a verify call */
55 
56 #ifndef CONFIG_SLOB
57 
58 /* prototypes */
59 extern void __init kmem_cache_init(void);
60 
61 extern kmem_cache_t *kmem_cache_create(const char *, size_t, size_t, unsigned long,
62 				       void (*)(void *, kmem_cache_t *, unsigned long),
63 				       void (*)(void *, kmem_cache_t *, unsigned long));
64 extern int kmem_cache_destroy(kmem_cache_t *);
65 extern int kmem_cache_shrink(kmem_cache_t *);
66 extern void *kmem_cache_alloc(kmem_cache_t *, gfp_t);
67 extern void kmem_cache_free(kmem_cache_t *, void *);
68 extern unsigned int kmem_cache_size(kmem_cache_t *);
69 extern const char *kmem_cache_name(kmem_cache_t *);
70 extern kmem_cache_t *kmem_find_general_cachep(size_t size, gfp_t gfpflags);
71 
72 /* Size description struct for general caches. */
73 struct cache_sizes {
74 	size_t		 cs_size;
75 	kmem_cache_t	*cs_cachep;
76 	kmem_cache_t	*cs_dmacachep;
77 };
78 extern struct cache_sizes malloc_sizes[];
79 
80 #ifndef CONFIG_DEBUG_SLAB
81 extern void *__kmalloc(size_t, gfp_t);
82 #else
83 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
84 #define __kmalloc(size, flags) \
85     __kmalloc_track_caller(size, flags, __builtin_return_address(0))
86 #endif
87 
88 static inline void *kmalloc(size_t size, gfp_t flags)
89 {
90 	if (__builtin_constant_p(size)) {
91 		int i = 0;
92 #define CACHE(x) \
93 		if (size <= x) \
94 			goto found; \
95 		else \
96 			i++;
97 #include "kmalloc_sizes.h"
98 #undef CACHE
99 		{
100 			extern void __you_cannot_kmalloc_that_much(void);
101 			__you_cannot_kmalloc_that_much();
102 		}
103 found:
104 		return kmem_cache_alloc((flags & GFP_DMA) ?
105 			malloc_sizes[i].cs_dmacachep :
106 			malloc_sizes[i].cs_cachep, flags);
107 	}
108 	return __kmalloc(size, flags);
109 }
110 
111 extern void *kzalloc(size_t, gfp_t);
112 
113 /**
114  * kcalloc - allocate memory for an array. The memory is set to zero.
115  * @n: number of elements.
116  * @size: element size.
117  * @flags: the type of memory to allocate.
118  */
119 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
120 {
121 	if (n != 0 && size > INT_MAX / n)
122 		return NULL;
123 	return kzalloc(n * size, flags);
124 }
125 
126 extern void kfree(const void *);
127 extern unsigned int ksize(const void *);
128 
129 #ifdef CONFIG_NUMA
130 extern void *kmem_cache_alloc_node(kmem_cache_t *, gfp_t flags, int node);
131 extern void *kmalloc_node(size_t size, gfp_t flags, int node);
132 #else
133 static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int node)
134 {
135 	return kmem_cache_alloc(cachep, flags);
136 }
137 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
138 {
139 	return kmalloc(size, flags);
140 }
141 #endif
142 
143 extern int FASTCALL(kmem_cache_reap(int));
144 extern int FASTCALL(kmem_ptr_validate(kmem_cache_t *cachep, void *ptr));
145 
146 #else /* CONFIG_SLOB */
147 
148 /* SLOB allocator routines */
149 
150 void kmem_cache_init(void);
151 struct kmem_cache *kmem_find_general_cachep(size_t, gfp_t gfpflags);
152 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
153 	unsigned long,
154 	void (*)(void *, struct kmem_cache *, unsigned long),
155 	void (*)(void *, struct kmem_cache *, unsigned long));
156 int kmem_cache_destroy(struct kmem_cache *c);
157 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
158 void kmem_cache_free(struct kmem_cache *c, void *b);
159 const char *kmem_cache_name(struct kmem_cache *);
160 void *kmalloc(size_t size, gfp_t flags);
161 void *kzalloc(size_t size, gfp_t flags);
162 void kfree(const void *m);
163 unsigned int ksize(const void *m);
164 unsigned int kmem_cache_size(struct kmem_cache *c);
165 
166 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
167 {
168 	return kzalloc(n * size, flags);
169 }
170 
171 #define kmem_cache_shrink(d) (0)
172 #define kmem_cache_reap(a)
173 #define kmem_ptr_validate(a, b) (0)
174 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
175 #define kmalloc_node(s, f, n) kmalloc(s, f)
176 
177 #endif /* CONFIG_SLOB */
178 
179 /* System wide caches */
180 extern kmem_cache_t	*vm_area_cachep;
181 extern kmem_cache_t	*names_cachep;
182 extern kmem_cache_t	*files_cachep;
183 extern kmem_cache_t	*filp_cachep;
184 extern kmem_cache_t	*fs_cachep;
185 extern kmem_cache_t	*signal_cachep;
186 extern kmem_cache_t	*sighand_cachep;
187 extern kmem_cache_t	*bio_cachep;
188 
189 extern atomic_t slab_reclaim_pages;
190 
191 #endif	/* __KERNEL__ */
192 
193 #endif	/* _LINUX_SLAB_H */
194