[mirror_ubuntu-hirsute-kernel.git] / include / linux / slab_def.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_SLAB_DEF_H
#define	_LINUX_SLAB_DEF_H

#include <linux/reciprocal_div.h>

/*
 * Definitions unique to the original Linux SLAB allocator.
 */

struct kmem_cache {
	struct array_cache __percpu *cpu_cache;

/* 1) Cache tunables. Protected by slab_mutex */
	unsigned int batchcount;
	unsigned int limit;
	unsigned int shared;

	unsigned int size;
	struct reciprocal_value reciprocal_buffer_size;
/* 2) touched by every alloc & free from the backend */

	slab_flags_t flags;		/* constant flags */
	unsigned int num;		/* # of objs per slab */

/* 3) cache_grow/shrink */
	/* order of pgs per slab (2^n) */
	unsigned int gfporder;

	/* force GFP flags, e.g. GFP_DMA */
	gfp_t allocflags;

	size_t colour;			/* cache colouring range */
	unsigned int colour_off;	/* colour offset */
	struct kmem_cache *freelist_cache;
	unsigned int freelist_size;

	/* constructor func */
	void (*ctor)(void *obj);

/* 4) cache creation/removal */
	const char *name;
	struct list_head list;
	int refcount;
	int object_size;
	int align;

/* 5) statistics */
#ifdef CONFIG_DEBUG_SLAB
	unsigned long num_active;
	unsigned long num_allocations;
	unsigned long high_mark;
	unsigned long grown;
	unsigned long reaped;
	unsigned long errors;
	unsigned long max_freeable;
	unsigned long node_allocs;
	unsigned long node_frees;
	unsigned long node_overflow;
	atomic_t allochit;
	atomic_t allocmiss;
	atomic_t freehit;
	atomic_t freemiss;

	/*
	 * If debugging is enabled, then the allocator can add additional
	 * fields and/or padding to every object. 'size' contains the total
	 * object size including these internal fields, while 'obj_offset'
	 * and 'object_size' contain the offset to the user object and its
	 * size.
	 */
	int obj_offset;
#endif /* CONFIG_DEBUG_SLAB */

#ifdef CONFIG_MEMCG
	struct memcg_cache_params memcg_params;
#endif
#ifdef CONFIG_KASAN
	struct kasan_cache kasan_info;
#endif

#ifdef CONFIG_SLAB_FREELIST_RANDOM
	unsigned int *random_seq;
#endif

	unsigned int useroffset;	/* Usercopy region offset */
	unsigned int usersize;		/* Usercopy region size */

	struct kmem_cache_node *node[MAX_NUMNODES];
};

static inline void *nearest_obj(struct kmem_cache *cache, struct page *page,
				void *x)
{
	void *object = x - (x - page->s_mem) % cache->size;
	void *last_object = page->s_mem + (cache->num - 1) * cache->size;

	if (unlikely(object > last_object))
		return last_object;
	else
		return object;
}

/*
 * We want to avoid an expensive divide : (offset / cache->size)
 *   Using the fact that size is a constant for a particular cache,
 *   we can replace (offset / cache->size) by
 *   reciprocal_divide(offset, cache->reciprocal_buffer_size)
 */
static inline unsigned int obj_to_index(const struct kmem_cache *cache,
					const struct page *page, void *obj)
{
	u32 offset = (obj - page->s_mem);
	return reciprocal_divide(offset, cache->reciprocal_buffer_size);
}

#endif	/* _LINUX_SLAB_DEF_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
2e892f43 CL	2	#ifndef _LINUX_SLAB_DEF_H
	3	#define _LINUX_SLAB_DEF_H
	4
809fa972 HFS	5	#include <linux/reciprocal_div.h>
809fa972 HFS	6
2e892f43 CL	7	/*
2e892f43 CL	8	* Definitions unique to the original Linux SLAB allocator.
8eae985f PE	9	*/
	10
	11	struct kmem_cache {
bf0dea23 JK	12	struct array_cache __percpu *cpu_cache;
bf0dea23 JK	13
24755e2e	14	/* 1) Cache tunables. Protected by slab_mutex */
8eae985f PE	15	unsigned int batchcount;
	16	unsigned int limit;
	17	unsigned int shared;
	18
3b0efdfa	19	unsigned int size;
809fa972	20	struct reciprocal_value reciprocal_buffer_size;
b56efcf0	21	/* 2) touched by every alloc & free from the backend */
8eae985f	22
d50112ed	23	slab_flags_t flags; /* constant flags */
8eae985f PE	24	unsigned int num; /* # of objs per slab */
8eae985f PE	25
b56efcf0	26	/* 3) cache_grow/shrink */
8eae985f PE	27	/* order of pgs per slab (2^n) */
	28	unsigned int gfporder;
	29
	30	/* force GFP flags, e.g. GFP_DMA */
a618e89f	31	gfp_t allocflags;
8eae985f PE	32
	33	size_t colour; /* cache colouring range */
	34	unsigned int colour_off; /* colour offset */
8456a648 JK	35	struct kmem_cache *freelist_cache;
8456a648 JK	36	unsigned int freelist_size;
8eae985f PE	37
	38	/* constructor func */
	39	void (ctor)(void obj);
	40
b56efcf0	41	/* 4) cache creation/removal */
8eae985f	42	const char *name;
3b0efdfa CL	43	struct list_head list;
	44	int refcount;
	45	int object_size;
	46	int align;
8eae985f	47
b56efcf0	48	/* 5) statistics */
8eae985f PE	49	#ifdef CONFIG_DEBUG_SLAB
	50	unsigned long num_active;
	51	unsigned long num_allocations;
	52	unsigned long high_mark;
	53	unsigned long grown;
	54	unsigned long reaped;
	55	unsigned long errors;
	56	unsigned long max_freeable;
	57	unsigned long node_allocs;
	58	unsigned long node_frees;
	59	unsigned long node_overflow;
	60	atomic_t allochit;
	61	atomic_t allocmiss;
	62	atomic_t freehit;
	63	atomic_t freemiss;
	64
	65	/*
	66	* If debugging is enabled, then the allocator can add additional
05fec35e BH	67	* fields and/or padding to every object. 'size' contains the total
	68	* object size including these internal fields, while 'obj_offset'
	69	* and 'object_size' contain the offset to the user object and its
	70	* size.
8eae985f PE	71	*/
8eae985f PE	72	int obj_offset;
8eae985f	73	#endif /* CONFIG_DEBUG_SLAB */
127424c8 JW	74
127424c8 JW	75	#ifdef CONFIG_MEMCG
f7ce3190	76	struct memcg_cache_params memcg_params;
ba6c496e	77	#endif
7ed2f9e6 AP	78	#ifdef CONFIG_KASAN
	79	struct kasan_cache kasan_info;
	80	#endif
8eae985f	81
c7ce4f60	82	#ifdef CONFIG_SLAB_FREELIST_RANDOM
7c00fce9	83	unsigned int *random_seq;
c7ce4f60 TG	84	#endif
c7ce4f60 TG	85
7bbdb81e AD	86	unsigned int useroffset; /* Usercopy region offset */
7bbdb81e AD	87	unsigned int usersize; /* Usercopy region size */
8eb8284b	88
bf0dea23	89	struct kmem_cache_node *node[MAX_NUMNODES];
8eae985f PE	90	};
8eae985f PE	91
7ed2f9e6	92	static inline void nearest_obj(struct kmem_cache cache, struct page *page,
80a9201a AP	93	void *x)
80a9201a AP	94	{
7ed2f9e6 AP	95	void *object = x - (x - page->s_mem) % cache->size;
	96	void last_object = page->s_mem + (cache->num - 1) cache->size;
	97
	98	if (unlikely(object > last_object))
	99	return last_object;
	100	else
	101	return object;
	102	}
	103
5b7c4148 AK	104	/*
	105	* We want to avoid an expensive divide : (offset / cache->size)
	106	* Using the fact that size is a constant for a particular cache,
	107	* we can replace (offset / cache->size) by
	108	* reciprocal_divide(offset, cache->reciprocal_buffer_size)
	109	*/
	110	static inline unsigned int obj_to_index(const struct kmem_cache *cache,
	111	const struct page page, void obj)
	112	{
	113	u32 offset = (obj - page->s_mem);
	114	return reciprocal_divide(offset, cache->reciprocal_buffer_size);
	115	}
	116
2e892f43	117	#endif /* _LINUX_SLAB_DEF_H */