ice: Fix undersized tx_flags variable

As not all ICE_TX_FLAGS_* fit in current 16-bit limited
tx_flags field that was introduced in the Fixes commit,
VLAN-related information would be discarded completely.
As such, creating a vlan and trying to run ping through
would result in no traffic passing.

Fix that by refactoring tx_flags variable into flags only and
a separate variable that holds VLAN ID. As there is some space left,
type variable can fit between those two. Pahole reports no size
change to ice_tx_buf struct.

Fixes: aa1d3fa ("ice: Robustify cleaning/completing XDP Tx buffers")
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: JanJSokolowski

drivers/net/ethernet/intel/ice/ice_dcb_lib.c

@@ -932,10 +932,9 @@ ice_tx_prepare_vlan_flags_dcb(struct ice_tx_ring *tx_ring,
 	if ((first->tx_flags & ICE_TX_FLAGS_HW_VLAN ||
 	     first->tx_flags & ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN) ||
 	    skb->priority != TC_PRIO_CONTROL) {
-		first->tx_flags &= ~ICE_TX_FLAGS_VLAN_PR_M;
+		first->vid &= ~VLAN_PRIO_MASK;
 		/* Mask the lower 3 bits to set the 802.1p priority */
-		first->tx_flags |= (skb->priority & 0x7) <<
-				   ICE_TX_FLAGS_VLAN_PR_S;
+		first->vid |= (skb->priority << VLAN_PRIO_SHIFT) & VLAN_PRIO_MASK;
 		/* if this is not already set it means a VLAN 0 + priority needs
 		 * to be offloaded
 		 */

drivers/net/ethernet/intel/ice/ice_txrx.c

@@ -1664,8 +1664,7 @@ ice_tx_map(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first,
 
 	if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
 		td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
-		td_tag = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
-			  ICE_TX_FLAGS_VLAN_S;
+		td_tag = first->vid;
 	}
 
 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
@@ -1998,7 +1997,7 @@ ice_tx_prepare_vlan_flags(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first)
 	 * VLAN offloads exclusively so we only care about the VLAN ID here
 	 */
 	if (skb_vlan_tag_present(skb)) {
-		first->tx_flags |= skb_vlan_tag_get(skb) << ICE_TX_FLAGS_VLAN_S;
+		first->vid = skb_vlan_tag_get(skb);
 		if (tx_ring->flags & ICE_TX_FLAGS_RING_VLAN_L2TAG2)
 			first->tx_flags |= ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN;
 		else
@@ -2388,8 +2387,7 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
 		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
 					(ICE_TX_CTX_DESC_IL2TAG2 <<
 					ICE_TXD_CTX_QW1_CMD_S));
-		offload.cd_l2tag2 = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
-			ICE_TX_FLAGS_VLAN_S;
+		offload.cd_l2tag2 = first->vid;
 	}
 
 	/* set up TSO offload */

drivers/net/ethernet/intel/ice/ice_txrx.h

@@ -127,10 +127,6 @@ static inline int ice_skb_pad(void)
 #define ICE_TX_FLAGS_IPV6	BIT(6)
 #define ICE_TX_FLAGS_TUNNEL	BIT(7)
 #define ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN	BIT(8)
-#define ICE_TX_FLAGS_VLAN_M	0xffff0000
-#define ICE_TX_FLAGS_VLAN_PR_M	0xe0000000
-#define ICE_TX_FLAGS_VLAN_PR_S	29
-#define ICE_TX_FLAGS_VLAN_S	16
 
 #define ICE_XDP_PASS		0
 #define ICE_XDP_CONSUMED	BIT(0)
@@ -182,8 +178,9 @@ struct ice_tx_buf {
 		unsigned int gso_segs;
 		unsigned int nr_frags;	/* used for mbuf XDP */
 	};
-	u32 type:16;			/* &ice_tx_buf_type */
-	u32 tx_flags:16;
+	u32 tx_flags:12;
+	u32 type:4;			/* &ice_tx_buf_type */
+	u32 vid:16;
 	DEFINE_DMA_UNMAP_LEN(len);
 	DEFINE_DMA_UNMAP_ADDR(dma);
 };