1 files changed, 57 insertions, 0 deletions

diff --git a/fs/xfs/xfs_mru_cache.h b/fs/xfs/xfs_mru_cache.h
new file mode 100644
index 000000000000..624fd10ee8e5
--- /dev/null
+++ b/fs/xfs/xfs_mru_cache.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2006-2007 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#ifndef __XFS_MRU_CACHE_H__
+#define __XFS_MRU_CACHE_H__
+
+
+/* Function pointer type for callback to free a client's data pointer. */
+typedef void (*xfs_mru_cache_free_func_t)(unsigned long, void*);
+
+typedef struct xfs_mru_cache
+{
+        struct radix_tree_root  store;     /* Core storage data structure.  */
+        struct list_head        *lists;    /* Array of lists, one per grp.  */
+        struct list_head        reap_list; /* Elements overdue for reaping. */
+        spinlock_t              lock;      /* Lock to protect this struct.  */
+        unsigned int            grp_count; /* Number of discrete groups.    */
+        unsigned int            grp_time;  /* Time period spanned by grps.  */
+        unsigned int            lru_grp;   /* Group containing time zero.   */
+        unsigned long           time_zero; /* Time first element was added. */
+        unsigned long           next_reap; /* Time that the reaper should
+                                              next do something. */
+        unsigned int            reap_all;  /* if set, reap all lists */
+        xfs_mru_cache_free_func_t free_func; /* Function pointer for freeing. */
+        struct delayed_work     work;      /* Workqueue data for reaping.   */
+} xfs_mru_cache_t;
+
+int xfs_mru_cache_init(void);
+void xfs_mru_cache_uninit(void);
+int xfs_mru_cache_create(struct xfs_mru_cache **mrup, unsigned int lifetime_ms,
+                             unsigned int grp_count,
+                             xfs_mru_cache_free_func_t free_func);
+void xfs_mru_cache_flush(xfs_mru_cache_t *mru, int restart);
+void xfs_mru_cache_destroy(struct xfs_mru_cache *mru);
+int xfs_mru_cache_insert(struct xfs_mru_cache *mru, unsigned long key,
+                                void *value);
+void * xfs_mru_cache_remove(struct xfs_mru_cache *mru, unsigned long key);
+void xfs_mru_cache_delete(struct xfs_mru_cache *mru, unsigned long key);
+void *xfs_mru_cache_lookup(struct xfs_mru_cache *mru, unsigned long key);
+void *xfs_mru_cache_peek(struct xfs_mru_cache *mru, unsigned long key);
+void xfs_mru_cache_done(struct xfs_mru_cache *mru);
+
+#endif /* __XFS_MRU_CACHE_H__ */