Kernel bump from 4.1.3-rt to 4.1.7-rt.

[kvmfornfv.git] / kernel / drivers / md / dm-cache-policy.h

diff --git a/kernel/drivers/md/dm-cache-policy.h b/kernel/drivers/md/dm-cache-policy.h
index f50fe36..5524e21 100644 (file)
--- a/kernel/drivers/md/dm-cache-policy.h
+++ b/kernel/drivers/md/dm-cache-policy.h
@@ -69,6 +69,18 @@ enum policy_operation {
        POLICY_REPLACE
 };
 
+/*
+ * When issuing a POLICY_REPLACE the policy needs to make a callback to
+ * lock the block being demoted.  This doesn't need to occur during a
+ * writeback operation since the block remains in the cache.
+ */
+struct policy_locker;
+typedef int (*policy_lock_fn)(struct policy_locker *l, dm_oblock_t oblock);
+
+struct policy_locker {
+       policy_lock_fn fn;
+};
+
 /*
  * This is the instruction passed back to the core target.
  */
@@ -122,7 +134,8 @@ struct dm_cache_policy {
         */
        int (*map)(struct dm_cache_policy *p, dm_oblock_t oblock,
                   bool can_block, bool can_migrate, bool discarded_oblock,
-                  struct bio *bio, struct policy_result *result);
+                  struct bio *bio, struct policy_locker *locker,
+                  struct policy_result *result);
 
        /*
         * Sometimes we want to see if a block is in the cache, without