IB/rdmavt: Eliminate redundant opcode test in mr ref clear

The use of the specific opcode test is redundant since
all ack entry users correctly manipulate the mr pointer
to selectively trigger the reference clearing.

The overly specific test hinders the use of implementation
specific operations.

The change needs to get rid of the union to insure that
an atomic value is not seen as an MR pointer.

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/sw/rdmavt/qp.c

@@ -435,8 +435,7 @@ static void rvt_clear_mr_refs(struct rvt_qp *qp, int clr_sends)
 	for (n = 0; n < rvt_max_atomic(rdi); n++) {
 		struct rvt_ack_entry *e = &qp->s_ack_queue[n];
 
-		if (e->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST &&
-		    e->rdma_sge.mr) {
+		if (e->rdma_sge.mr) {
 			rvt_put_mr(e->rdma_sge.mr);
 			e->rdma_sge.mr = NULL;
 		}

include/rdma/rdmavt_qp.h

@@ -222,14 +222,12 @@ struct rvt_mmap_info {
  * to send a RDMA read response or atomic operation.
  */
 struct rvt_ack_entry {
-	u8 opcode;
-	u8 sent;
+	struct rvt_sge rdma_sge;
+	u64 atomic_data;
 	u32 psn;
 	u32 lpsn;
-	union {
-		struct rvt_sge rdma_sge;
-		u64 atomic_data;
-	};
+	u8 opcode;
+	u8 sent;
 };
 
 #define	RC_QP_SCALING_INTERVAL	5