qede: Linearize SKBs when needed
There's a corner-case in HW where an SKB queued for transmission that
contains too many frags will cause FW to assert.
This patch solves this by linearizing the SKB if necessary.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c b/drivers/net/ethernet/qlogic/qede/qede_main.c
index 76fa5d7..f07b9a9 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_main.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
@@ -380,6 +380,28 @@
return 0;
}
+/* +2 for 1st BD for headers and 2nd BD for headlen (if required) */
+#if ((MAX_SKB_FRAGS + 2) > ETH_TX_MAX_BDS_PER_NON_LSO_PACKET)
+static bool qede_pkt_req_lin(struct qede_dev *edev, struct sk_buff *skb,
+ u8 xmit_type)
+{
+ int allowed_frags = ETH_TX_MAX_BDS_PER_NON_LSO_PACKET - 1;
+
+ if (xmit_type & XMIT_LSO) {
+ int hlen;
+
+ hlen = skb_transport_header(skb) +
+ tcp_hdrlen(skb) - skb->data;
+
+ /* linear payload would require its own BD */
+ if (skb_headlen(skb) > hlen)
+ allowed_frags--;
+ }
+
+ return (skb_shinfo(skb)->nr_frags > allowed_frags);
+}
+#endif
+
/* Main transmit function */
static
netdev_tx_t qede_start_xmit(struct sk_buff *skb,
@@ -407,16 +429,22 @@
txq = QEDE_TX_QUEUE(edev, txq_index);
netdev_txq = netdev_get_tx_queue(ndev, txq_index);
- /* Current code doesn't support SKB linearization, since the max number
- * of skb frags can be passed in the FW HSI.
- */
- BUILD_BUG_ON(MAX_SKB_FRAGS > ETH_TX_MAX_BDS_PER_NON_LSO_PACKET);
-
WARN_ON(qed_chain_get_elem_left(&txq->tx_pbl) <
(MAX_SKB_FRAGS + 1));
xmit_type = qede_xmit_type(edev, skb, &ipv6_ext);
+#if ((MAX_SKB_FRAGS + 2) > ETH_TX_MAX_BDS_PER_NON_LSO_PACKET)
+ if (qede_pkt_req_lin(edev, skb, xmit_type)) {
+ if (skb_linearize(skb)) {
+ DP_NOTICE(edev,
+ "SKB linearization failed - silently dropping this SKB\n");
+ dev_kfree_skb_any(skb);
+ return NETDEV_TX_OK;
+ }
+ }
+#endif
+
/* Fill the entry in the SW ring and the BDs in the FW ring */
idx = txq->sw_tx_prod & NUM_TX_BDS_MAX;
txq->sw_tx_ring[idx].skb = skb;