xref: /OK3568_Linux_fs/kernel/drivers/md/dm-cache-background-tracker.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (C) 2017 Red Hat. All rights reserved.
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * This file is released under the GPL.
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #ifndef DM_CACHE_BACKGROUND_WORK_H
8*4882a593Smuzhiyun #define DM_CACHE_BACKGROUND_WORK_H
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <linux/vmalloc.h>
11*4882a593Smuzhiyun #include "dm-cache-policy.h"
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun /*----------------------------------------------------------------*/
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun struct background_work;
16*4882a593Smuzhiyun struct background_tracker;
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun  * FIXME: discuss lack of locking in all methods.
20*4882a593Smuzhiyun  */
21*4882a593Smuzhiyun struct background_tracker *btracker_create(unsigned max_work);
22*4882a593Smuzhiyun void btracker_destroy(struct background_tracker *b);
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun unsigned btracker_nr_writebacks_queued(struct background_tracker *b);
25*4882a593Smuzhiyun unsigned btracker_nr_demotions_queued(struct background_tracker *b);
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun /*
28*4882a593Smuzhiyun  * returns -EINVAL iff the work is already queued.  -ENOMEM if the work
29*4882a593Smuzhiyun  * couldn't be queued for another reason.
30*4882a593Smuzhiyun  */
31*4882a593Smuzhiyun int btracker_queue(struct background_tracker *b,
32*4882a593Smuzhiyun 		   struct policy_work *work,
33*4882a593Smuzhiyun 		   struct policy_work **pwork);
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun /*
36*4882a593Smuzhiyun  * Returns -ENODATA if there's no work.
37*4882a593Smuzhiyun  */
38*4882a593Smuzhiyun int btracker_issue(struct background_tracker *b, struct policy_work **work);
39*4882a593Smuzhiyun void btracker_complete(struct background_tracker *b,
40*4882a593Smuzhiyun 		       struct policy_work *op);
41*4882a593Smuzhiyun bool btracker_promotion_already_present(struct background_tracker *b,
42*4882a593Smuzhiyun 					dm_oblock_t oblock);
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun /*----------------------------------------------------------------*/
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun #endif
47