bna: TX Queue Depth Fix

sk_buff unmap_array grows greater than 65536 (x2) with Tx ring of 65536.
Reducing TXQ depth and safe(max) acking of Tx events to 32768 (same as Rx).
Add defines for TX and RX queue depths.
Signed-off-by: NGurunatha Karaje <gkaraje@brocade.com>
Signed-off-by: NRasesh Mody <rmody@brocade.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/brocade/bna/bnad.h

@@ -86,6 +86,10 @@ struct bnad_rx_ctrl {
 #define BNAD_MAX_Q_DEPTH		0x10000
 #define BNAD_MIN_Q_DEPTH		0x200
 
+#define BNAD_MAX_RXQ_DEPTH		(BNAD_MAX_Q_DEPTH / bnad_rxqs_per_cq)
+/* keeping MAX TX and RX Q depth equal */
+#define BNAD_MAX_TXQ_DEPTH		BNAD_MAX_RXQ_DEPTH
+
 #define BNAD_JUMBO_MTU			9000
 
 #define BNAD_NETIF_WAKE_THRESHOLD	8

drivers/net/ethernet/brocade/bna/bnad_ethtool.c

@@ -418,10 +418,10 @@ bnad_get_ringparam(struct net_device *netdev,
 {
 	struct bnad *bnad = netdev_priv(netdev);
 
-	ringparam->rx_max_pending = BNAD_MAX_Q_DEPTH / bnad_rxqs_per_cq;
+	ringparam->rx_max_pending = BNAD_MAX_RXQ_DEPTH;
 	ringparam->rx_mini_max_pending = 0;
 	ringparam->rx_jumbo_max_pending = 0;
-	ringparam->tx_max_pending = BNAD_MAX_Q_DEPTH;
+	ringparam->tx_max_pending = BNAD_MAX_TXQ_DEPTH;
 
 	ringparam->rx_pending = bnad->rxq_depth;
 	ringparam->rx_mini_max_pending = 0;
@@ -445,13 +445,13 @@ bnad_set_ringparam(struct net_device *netdev,
 	}
 
 	if (ringparam->rx_pending < BNAD_MIN_Q_DEPTH ||
-	    ringparam->rx_pending > BNAD_MAX_Q_DEPTH / bnad_rxqs_per_cq ||
+	    ringparam->rx_pending > BNAD_MAX_RXQ_DEPTH ||
 	    !BNA_POWER_OF_2(ringparam->rx_pending)) {
 		mutex_unlock(&bnad->conf_mutex);
 		return -EINVAL;
 	}
 	if (ringparam->tx_pending < BNAD_MIN_Q_DEPTH ||
-	    ringparam->tx_pending > BNAD_MAX_Q_DEPTH ||
+	    ringparam->tx_pending > BNAD_MAX_TXQ_DEPTH ||
 	    !BNA_POWER_OF_2(ringparam->tx_pending)) {
 		mutex_unlock(&bnad->conf_mutex);
 		return -EINVAL;