+/*
+ * The caching code relies on locking provided by the user of
+ * struct ocfs2_caching_info. These operations connect that up.
+ */
+struct ocfs2_caching_operations {
+ /*
+ * A u64 representing the owning structure. Usually this
+ * is the block number (i_blkno or whatnot). This is used so
+ * that caching log messages can identify the owning structure.
+ */
+ u64 (*co_owner)(struct ocfs2_caching_info *ci);
+
+ /* The superblock is needed during I/O. */
+ struct super_block *(*co_get_super)(struct ocfs2_caching_info *ci);
+ /*
+ * Lock and unlock the caching data. These will not sleep, and
+ * should probably be spinlocks.
+ */
+ void (*co_cache_lock)(struct ocfs2_caching_info *ci);
+ void (*co_cache_unlock)(struct ocfs2_caching_info *ci);
+
+ /*
+ * Lock and unlock for disk I/O. These will sleep, and should
+ * be mutexes.
+ */
+ void (*co_io_lock)(struct ocfs2_caching_info *ci);
+ void (*co_io_unlock)(struct ocfs2_caching_info *ci);
+};
+