/*
* 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__ */
