linux - include/linux/mbcache.h

52 lines · 1.6 KiB

1	/* SPDX-License-Identifier: GPL-2.0 */
2	#ifndef _LINUX_MBCACHE_H
3	#define _LINUX_MBCACHE_H
4
5	#include <linux/hash.h>
6	#include <linux/list_bl.h>
7	#include <linux/list.h>
8	#include <linux/atomic.h>
9	#include <linux/fs.h>
10
11	struct mb_cache;
12
13	struct mb_cache_entry {
14	/* List of entries in cache - protected by cache->c_list_lock */
15	struct list_head e_list;
16	/* Hash table list - protected by hash chain bitlock */
17	struct hlist_bl_node e_hash_list;
18	atomic_t e_refcnt;
19	/* Key in hash - stable during lifetime of the entry */
20	u32 e_key;
21	u32 e_referenced:1;
22	u32 e_reusable:1;
23	/* User provided value - stable during lifetime of the entry */
24	u64 e_value;
25	};
26
27	struct mb_cache *mb_cache_create(int bucket_bits);
28	void mb_cache_destroy(struct mb_cache *cache);
29
30	int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key,
31	u64 value, bool reusable);
32	void __mb_cache_entry_free(struct mb_cache_entry *entry);
33	static inline int mb_cache_entry_put(struct mb_cache *cache,
34	struct mb_cache_entry *entry)
35	{
36	if (!atomic_dec_and_test(&entry->e_refcnt))
37	return 0;
38	__mb_cache_entry_free(entry);
39	return 1;
40	}
41
42	void mb_cache_entry_delete(struct mb_cache *cache, u32 key, u64 value);
43	struct mb_cache_entry mb_cache_entry_get(struct mb_cache cache, u32 key,
44	u64 value);
45	struct mb_cache_entry mb_cache_entry_find_first(struct mb_cache cache,
46	u32 key);
47	struct mb_cache_entry mb_cache_entry_find_next(struct mb_cache cache,
48	struct mb_cache_entry *entry);
49	void mb_cache_entry_touch(struct mb_cache *cache,
50	struct mb_cache_entry *entry);
51
52	#endif /* _LINUX_MBCACHE_H */