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 <redacted>
Signed-off-by: Amir Vadai <redacted>
---
drivers/net/ethernet/mellanox/mlx4/en_tx.c | 3 ++-
include/linux/mlx4/qp.h | 11 ++++++++---
2 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 9730373..fda88a8 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -877,7 +877,8 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
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 @@ enum {
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)--
1.8.3.4