OpenCloudOS-Kernel/drivers/md/dm-cache-background-tracker.h

47 lines
1.3 KiB
C
Raw Normal View History

/*
* Copyright (C) 2017 Red Hat. All rights reserved.
*
* This file is released under the GPL.
*/
#ifndef DM_CACHE_BACKGROUND_WORK_H
#define DM_CACHE_BACKGROUND_WORK_H
#include <linux/vmalloc.h>
#include "dm-cache-policy.h"
/*----------------------------------------------------------------*/
struct background_work;
struct background_tracker;
/*
* FIXME: discuss lack of locking in all methods.
*/
struct background_tracker *btracker_create(unsigned max_work);
void btracker_destroy(struct background_tracker *b);
unsigned btracker_nr_writebacks_queued(struct background_tracker *b);
unsigned btracker_nr_demotions_queued(struct background_tracker *b);
/*
* returns -EINVAL iff the work is already queued. -ENOMEM if the work
* couldn't be queued for another reason.
*/
int btracker_queue(struct background_tracker *b,
struct policy_work *work,
struct policy_work **pwork);
/*
* Returns -ENODATA if there's no work.
*/
int btracker_issue(struct background_tracker *b, struct policy_work **work);
void btracker_complete(struct background_tracker *b,
struct policy_work *op);
bool btracker_promotion_already_present(struct background_tracker *b,
dm_oblock_t oblock);
/*----------------------------------------------------------------*/
#endif