net/mlx4_en: Use union for BlueFlame WQE
When BlueFlame is turned on, control segment of the TX WQE is changed,
and the second line of it is used for QPN.
Changed code to use a union in the mlx4_wqe_ctrl_seg instead of casting.
This makes the code clearer and solves the static checker warning:
drivers/net/ethernet/mellanox/mlx4/en_tx.c:839 mlx4_en_xmit()
warn: potential memory corrupting cast 4 vs 2 bytes
CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 56e8fbc..69c2fce 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -876,7 +876,8 @@
skb_tx_timestamp(skb);
if (ring->bf_enabled && desc_size <= MAX_BF && !bounce && !vlan_tx_tag_present(skb)) {
- *(__be32 *) (&tx_desc->ctrl.vlan_tag) |= cpu_to_be32(ring->doorbell_qpn);
+ tx_desc->ctrl.bf_qpn |= cpu_to_be32(ring->doorbell_qpn);
+
op_own |= htonl((bf_index & 0xffff) << 8);
/* Ensure new descirptor hits memory
* before setting ownership of this descriptor to HW */
diff --git a/include/linux/mlx4/qp.h b/include/linux/mlx4/qp.h
index 59f8ba8..b66e761 100644
--- a/include/linux/mlx4/qp.h
+++ b/include/linux/mlx4/qp.h
@@ -270,9 +270,14 @@
struct mlx4_wqe_ctrl_seg {
__be32 owner_opcode;
- __be16 vlan_tag;
- u8 ins_vlan;
- u8 fence_size;
+ union {
+ struct {
+ __be16 vlan_tag;
+ u8 ins_vlan;
+ u8 fence_size;
+ };
+ __be32 bf_qpn;
+ };
/*
* High 24 bits are SRC remote buffer; low 8 bits are flags:
* [7] SO (strong ordering)