From 532906aa7f9656209f30f08dfadd328fc1bc6912 Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Fri, 8 Nov 2013 16:36:17 +0000 Subject: 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: Joe Thornber Signed-off-by: Mike Snitzer --- drivers/md/dm-cache-policy.h | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'drivers/md/dm-cache-policy.h') diff --git a/drivers/md/dm-cache-policy.h b/drivers/md/dm-cache-policy.h index 33369ca9614f..052c00a84a5c 100644 --- a/drivers/md/dm-cache-policy.h +++ b/drivers/md/dm-cache-policy.h @@ -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? -- cgit v1.2.3