[dm-cache] The CLEAN_SHUTDOWN flag was not being set

jthornber · jthornber · commit 7e0a9739fd9e · 2015-10-22T18:10:55.000+01:00
or rather, it was being set on the disk, then immediately cleared again.

If the CLEAN_SHUTDOWN flag is not set when a cache is loaded then all cache
blocks are marked as dirty and a full writeback occurs.
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
@@ -634,10 +634,11 @@ static int __commit_transaction(struct dm_cache_metadata *cmd,
 
 	disk_super = dm_block_data(sblock);
 
+	disk_super->flags = cpu_to_le32(cmd->flags);
+
 	if (mutator)
 		update_flags(disk_super, mutator);
 
-	disk_super->flags = cpu_to_le32(cmd->flags);
 	disk_super->mapping_root = cpu_to_le64(cmd->root);
 	disk_super->hint_root = cpu_to_le64(cmd->hint_root);
 	disk_super->discard_root = cpu_to_le64(cmd->discard_root);
