8  * Initialize a cache object.
10  * @cache:      The cache.
11  * @max_size:   Maximum size (number of entries) for the cache.
13  *              trim the cache in that case.
15 void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size)  in btrfs_lru_cache_init()  argument
17 	INIT_LIST_HEAD(&cache->lru_list);  in btrfs_lru_cache_init()
18 	mt_init(&cache->entries);  in btrfs_lru_cache_init()
19 	cache->size = 0;  in btrfs_lru_cache_init()
20 	cache->max_size = max_size;  in btrfs_lru_cache_init()
37  * Lookup for an entry in the cache.
39  * @cache:      The cache.
45 struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache,  in btrfs_lru_cache_lookup()  argument
51 	head = mtree_load(&cache->entries, key);  in btrfs_lru_cache_lookup()
57 		list_move_tail(&entry->lru_list, &cache->lru_list);  in btrfs_lru_cache_lookup()
63  * Remove an entry from the cache.
65  * @cache:     The cache to remove from.
66  * @entry:     The entry to remove from the cache.
70 void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache,  in btrfs_lru_cache_remove()  argument
75 	ASSERT(cache->size > 0);  in btrfs_lru_cache_remove()
76 	ASSERT(!mtree_empty(&cache->entries));  in btrfs_lru_cache_remove()
89 		head = mtree_erase(&cache->entries, entry->key);  in btrfs_lru_cache_remove()
95 	cache->size--;  in btrfs_lru_cache_remove()
99  * Store an entry in the cache.
101  * @cache:      The cache.
106 int btrfs_lru_cache_store(struct btrfs_lru_cache *cache,  in btrfs_lru_cache_store()  argument
118 	ret = mtree_insert(&cache->entries, key, head, gfp);  in btrfs_lru_cache_store()
124 		head = mtree_load(&cache->entries, key);  in btrfs_lru_cache_store()
134 	if (cache->max_size > 0 && cache->size == cache->max_size) {  in btrfs_lru_cache_store()
137 		lru_entry = list_first_entry(&cache->lru_list,  in btrfs_lru_cache_store()
140 		btrfs_lru_cache_remove(cache, lru_entry);  in btrfs_lru_cache_store()
143 	list_add_tail(&new_entry->lru_list, &cache->lru_list);  in btrfs_lru_cache_store()
144 	cache->size++;  in btrfs_lru_cache_store()
150  * Empty a cache.
152  * @cache:     The cache to empty.
154  * Removes all entries from the cache.
156 void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache)  in btrfs_lru_cache_clear()  argument
161 	list_for_each_entry_safe(entry, tmp, &cache->lru_list, lru_list)  in btrfs_lru_cache_clear()
162 		btrfs_lru_cache_remove(cache, entry);  in btrfs_lru_cache_clear()
164 	ASSERT(cache->size == 0);  in btrfs_lru_cache_clear()
165 	ASSERT(mtree_empty(&cache->entries));  in btrfs_lru_cache_clear()