IB/core: Fix and clean up ib_ud_header_init()

ib_ud_header_init() first clears header and then fills up the various
fields. Later on, it tests header->immediate_present, which it has
already cleared, so the condition is always false. Fix this by adding
an immediate_present parameter and setting header->immediate_present
as is done with grh_present. Also remove unused calculation of
header_len.

Signed-off-by: Eli Cohen <[e-mail]>
Signed-off-by: Roland Dreier <[e-mail]>

drivers/infiniband/core/ud_header.c

···
  * ib_ud_header_init - Initialize UD header structure
  * @payload_bytes:Length of packet payload
  * @grh_present:GRH flag (if non-zero, GRH will be included)
+ * @immediate_present: specify if immediate data should be used
  * @header:Structure to initialize
  *
  * ib_ud_header_init() initializes the lrh.link_version, lrh.link_next_header,
···
  */
 void ib_ud_header_init(int     		    payload_bytes,
 		       int    		    grh_present,
+		       int		    immediate_present,
 		       struct ib_ud_header *header)
 {
-	int header_len;
 	u16 packet_length;
 
 	memset(header, 0, sizeof *header);
-
-	header_len =
-		IB_LRH_BYTES  +
-		IB_BTH_BYTES  +
-		IB_DETH_BYTES;
-	if (grh_present) {
-		header_len += IB_GRH_BYTES;
-	}
 
 	header->lrh.link_version     = 0;
 	header->lrh.link_next_header =
···
 
 	header->lrh.packet_length = cpu_to_be16(packet_length);
 
-	if (header->immediate_present)
+	header->immediate_present	     = immediate_present;
+	if (immediate_present)
 		header->bth.opcode           = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
 	else
 		header->bth.opcode           = IB_OPCODE_UD_SEND_ONLY;

drivers/infiniband/hw/mlx4/qp.c

···
 	for (i = 0; i < wr->num_sge; ++i)
 		send_size += wr->sg_list[i].length;
 
-	ib_ud_header_init(send_size, mlx4_ib_ah_grh_present(ah), &sqp->ud_header);
+	ib_ud_header_init(send_size, mlx4_ib_ah_grh_present(ah), 0, &sqp->ud_header);
 
 	sqp->ud_header.lrh.service_level   =
 		be32_to_cpu(ah->av.sl_tclass_flowlabel) >> 28;

drivers/infiniband/hw/mthca/mthca_qp.c

···
 	u16 pkey;
 
 	ib_ud_header_init(256, /* assume a MAD */
-			  mthca_ah_grh_present(to_mah(wr->wr.ud.ah)),
+			  mthca_ah_grh_present(to_mah(wr->wr.ud.ah)), 0,
 			  &sqp->ud_header);
 
 	err = mthca_read_ah(dev, to_mah(wr->wr.ud.ah), &sqp->ud_header);

include/rdma/ib_pack.h

···
 
 void ib_ud_header_init(int     		   payload_bytes,
 		       int    		   grh_present,
+		       int		   immediate_present,
 		       struct ib_ud_header *header);
 
 int ib_ud_header_pack(struct ib_ud_header *header,