Commit 532906aa authored by Joe Thornber's avatar Joe Thornber Committed by Mike Snitzer

dm cache: add remove_cblock method to policy interface

Implement policy_remove_cblock() and add remove_cblock method to the mq
policy.  These methods will be used by the following cache block
invalidation patch which adds the 'invalidate_cblocks' message to the
cache core.

Also, update some comments in dm-cache-policy.h
Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 633618e3
......@@ -64,6 +64,11 @@ static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t
p->remove_mapping(p, oblock);
}
static inline int policy_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock)
{
return p->remove_cblock(p, cblock);
}
static inline void policy_force_mapping(struct dm_cache_policy *p,
dm_oblock_t current_oblock, dm_oblock_t new_oblock)
{
......
......@@ -304,6 +304,15 @@ static void free_entry(struct entry_pool *ep, struct entry *e)
list_add(&e->list, &ep->free);
}
/*
* Returns NULL if the entry is free.
*/
static struct entry *epool_find(struct entry_pool *ep, dm_cblock_t cblock)
{
struct entry *e = ep->entries + from_cblock(cblock);
return e->hlist.pprev ? e : NULL;
}
static bool epool_empty(struct entry_pool *ep)
{
return list_empty(&ep->free);
......@@ -1020,6 +1029,31 @@ static void mq_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock)
mutex_unlock(&mq->lock);
}
static int __remove_cblock(struct mq_policy *mq, dm_cblock_t cblock)
{
struct entry *e = epool_find(&mq->cache_pool, cblock);
if (!e)
return -ENODATA;
del(mq, e);
free_entry(&mq->cache_pool, e);
return 0;
}
static int mq_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock)
{
int r;
struct mq_policy *mq = to_mq_policy(p);
mutex_lock(&mq->lock);
r = __remove_cblock(mq, cblock);
mutex_unlock(&mq->lock);
return r;
}
static int __mq_writeback_work(struct mq_policy *mq, dm_oblock_t *oblock,
dm_cblock_t *cblock)
{
......@@ -1139,6 +1173,7 @@ static void init_policy_functions(struct mq_policy *mq)
mq->policy.load_mapping = mq_load_mapping;
mq->policy.walk_mappings = mq_walk_mappings;
mq->policy.remove_mapping = mq_remove_mapping;
mq->policy.remove_cblock = mq_remove_cblock;
mq->policy.writeback_work = mq_writeback_work;
mq->policy.force_mapping = mq_force_mapping;
mq->policy.residency = mq_residency;
......
......@@ -135,9 +135,6 @@ struct dm_cache_policy {
*/
int (*lookup)(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock);
/*
* oblock must be a mapped block. Must not block.
*/
void (*set_dirty)(struct dm_cache_policy *p, dm_oblock_t oblock);
void (*clear_dirty)(struct dm_cache_policy *p, dm_oblock_t oblock);
......@@ -159,8 +156,24 @@ struct dm_cache_policy {
void (*force_mapping)(struct dm_cache_policy *p, dm_oblock_t current_oblock,
dm_oblock_t new_oblock);
int (*writeback_work)(struct dm_cache_policy *p, dm_oblock_t *oblock, dm_cblock_t *cblock);
/*
* This is called via the invalidate_cblocks message. It is
* possible the particular cblock has already been removed due to a
* write io in passthrough mode. In which case this should return
* -ENODATA.
*/
int (*remove_cblock)(struct dm_cache_policy *p, dm_cblock_t cblock);
/*
* Provide a dirty block to be written back by the core target.
*
* Returns:
*
* 0 and @cblock,@oblock: block to write back provided
*
* -ENODATA: no dirty blocks available
*/
int (*writeback_work)(struct dm_cache_policy *p, dm_oblock_t *oblock, dm_cblock_t *cblock);
/*
* How full is the cache?
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment