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Diffstat (limited to 'fs/xfs/xfs_mru_cache.h')
-rw-r--r--fs/xfs/xfs_mru_cache.h57
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diff --git a/fs/xfs/xfs_mru_cache.h b/fs/xfs/xfs_mru_cache.h
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+++ 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__ */