burn in one shot

actors/verifreg/src/lib.rs

@@ -375,6 +375,7 @@ impl Actor {
         }
 
         let mut rets: Vec<ClaimAllocationsReturn> = Vec::new();
+        let mut total_datacap_claimed = DataCap::zero();
 
         for p in params.claims {
             let mut datacap_claimed = DataCap::zero();
@@ -460,12 +461,15 @@ impl Actor {
                 ));
             }
 
-            // Burn the datacap tokens from verified registry's own balance.
-            burn(rt, &datacap_claimed)?;
+            // accumulate burnt datacap
+            total_datacap_claimed += datacap_claimed.clone();
 
             rets.push(ClaimAllocationsReturn { batch_info, claimed_space: datacap_claimed });
         }
 
+        // burn all the claimed datacap
+        burn(rt, &total_datacap_claimed)?;
+
         Ok(ClaimAllocationsBatchReturn { claims: rets })
     }
     // Called by storage provider actor to claim allocations for data provably committed to storage.