diff --git a/dm-compress/compress.c b/dm-compress/compress.c
index f87ad4c..275ecb5 100644
--- a/dm-compress/compress.c
+++ b/dm-compress/compress.c
@@ -67,7 +67,7 @@ static struct kobject* compress_kobj;
 static inline u64
 dm_target_pblk_size(struct dm_target* ti, struct cbd_params* params)
 {
-    return ti->len * (pblk_size(params) >> SECTOR_SHIFT);
+    return ti->len >> params->pblk_shift;
 }
 
 /**************************************