svcrdma: Clean-up svc_rdma_unmap_dma

There's no longer a need to compare each SGE's lkey with the PD's
local_dma_lkey. Now that FRWR is gone, all DMA mappings are for
pages that were registered with this key.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

net/sunrpc/xprtrdma/svc_rdma_transport.c

@@ -225,22 +225,13 @@ void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
 {
 	struct svcxprt_rdma *xprt = ctxt->xprt;
 	struct ib_device *device = xprt->sc_cm_id->device;
-	u32 lkey = xprt->sc_pd->local_dma_lkey;
 	unsigned int i;
 
-	for (i = 0; i < ctxt->mapped_sges; i++) {
-		/*
-		 * Unmap the DMA addr in the SGE if the lkey matches
-		 * the local_dma_lkey, otherwise, ignore it since it is
-		 * an FRMR lkey and will be unmapped later when the
-		 * last WR that uses it completes.
-		 */
-		if (ctxt->sge[i].lkey == lkey)
-			ib_dma_unmap_page(device,
-					    ctxt->sge[i].addr,
-					    ctxt->sge[i].length,
-					    ctxt->direction);
-	}
+	for (i = 0; i < ctxt->mapped_sges; i++)
+		ib_dma_unmap_page(device,
+				  ctxt->sge[i].addr,
+				  ctxt->sge[i].length,
+				  ctxt->direction);
 	ctxt->mapped_sges = 0;
 }