1 files changed, 50 insertions, 0 deletions

diff --git a/include/linux/mbcache2.h b/include/linux/mbcache2.h
new file mode 100644
index 000000000000..b6f160ff2533
--- /dev/null
+++ b/include/linux/mbcache2.h
@@ -0,0 +1,50 @@
+#ifndef _LINUX_MB2CACHE_H
+#define _LINUX_MB2CACHE_H
+
+#include <linux/hash.h>
+#include <linux/list_bl.h>
+#include <linux/list.h>
+#include <linux/atomic.h>
+#include <linux/fs.h>
+
+struct mb2_cache;
+
+struct mb2_cache_entry {
+        /* LRU list - protected by cache->c_lru_list_lock */
+        struct list_head        e_lru_list;
+        /* Hash table list - protected by bitlock in e_hash_list_head */
+        struct hlist_bl_node    e_hash_list;
+        atomic_t                e_refcnt;
+        /* Key in hash - stable during lifetime of the entry */
+        u32                     e_key;
+        /* Block number of hashed block - stable during lifetime of the entry */
+        sector_t                e_block;
+        /* Head of hash list (for list bit lock) - stable */
+        struct hlist_bl_head    *e_hash_list_head;
+};
+
+struct mb2_cache *mb2_cache_create(int bucket_bits);
+void mb2_cache_destroy(struct mb2_cache *cache);
+
+int mb2_cache_entry_create(struct mb2_cache *cache, gfp_t mask, u32 key,
+                           sector_t block);
+void __mb2_cache_entry_free(struct mb2_cache_entry *entry);
+static inline int mb2_cache_entry_put(struct mb2_cache *cache,
+                                      struct mb2_cache_entry *entry)
+{
+        if (!atomic_dec_and_test(&entry->e_refcnt))
+                return 0;
+        __mb2_cache_entry_free(entry);
+        return 1;
+}
+
+void mb2_cache_entry_delete_block(struct mb2_cache *cache, u32 key,
+                                  sector_t block);
+struct mb2_cache_entry *mb2_cache_entry_find_first(struct mb2_cache *cache,
+                                                   u32 key);
+struct mb2_cache_entry *mb2_cache_entry_find_next(struct mb2_cache *cache,
+                                                  struct mb2_cache_entry *entry);
+void mb2_cache_entry_touch(struct mb2_cache *cache,
+                           struct mb2_cache_entry *entry);
+
+#endif  /* _LINUX_MB2CACHE_H */