bna: TX Path and RX Path Changes

Change details:
 - Add bnad_pci_unmap_skb() API to unmap skb from transmit path and update the
   unmap index. Add more checks for illegal skbs in transmit path. Add tx_skb
   counters for dropped skbs.
 - The unmap_cons index used in bnad_free_txbufs() is incorrectly declared as
   u16. It quickly wraps around and accesses null sk_buff ptr. So using u32 to
   handle unmap_array.
 - Disable and enable interrupts from the same polling context to prevent
   reordering in Rx path.
 - Add Rx NAPI debug counters.
 - Make NAPI budget check more generic.
 - Modify dim timer stop logic to make it dependent on cfg and run flags
 - Handle reduced MSI-X vectors case in bnad_enable_msix.
 - Check for single frame TSO skbs and send them out as non-TSO.
 - Put memory barrier after bna_txq_prod_indx_doorbell().
Signed-off-by: Gurunatha Karaje <gkaraje@brocade.com>
Signed-off-by: Rasesh Mody <rmody@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -56,6 +56,11 @@ struct bnad_rx_ctrl {
 	struct bnad *bnad;
 	unsigned long  flags;
 	struct napi_struct	napi;
+	u64		rx_intr_ctr;
+	u64		rx_poll_ctr;
+	u64		rx_schedule;
+	u64		rx_keep_poll;
+	u64		rx_complete;
 };
 
 #define BNAD_RXMODE_PROMISC_DEFAULT	BNA_RXMODE_PROMISC
@@ -148,6 +153,20 @@ struct bnad_drv_stats {
 	u64		udpcsum_offload;
 	u64		csum_help;
 	u64		csum_help_err;
+	u64		tx_skb_too_short;
+	u64		tx_skb_stopping;
+	u64		tx_skb_max_vectors;
+	u64		tx_skb_mss_too_long;
+	u64		tx_skb_tso_too_short;
+	u64		tx_skb_tso_prepare;
+	u64		tx_skb_non_tso_too_long;
+	u64		tx_skb_tcp_hdr;
+	u64		tx_skb_udp_hdr;
+	u64		tx_skb_csum_err;
+	u64		tx_skb_headlen_too_long;
+	u64		tx_skb_headlen_zero;
+	u64		tx_skb_frag_zero;
+	u64		tx_skb_len_mismatch;
 
 	u64		hw_stats_updates;
 	u64		netif_rx_schedule;
@@ -346,7 +365,7 @@ extern void bnad_netdev_hwstats_fill(struct bnad *bnad,
 
 #define bnad_enable_rx_irq_unsafe(_ccb)			\
 {							\
-	if (likely(test_bit(BNAD_RXQ_STARTED, &ccb->rcb[0]->flags))) {\
+	if (likely(test_bit(BNAD_RXQ_STARTED, &(_ccb)->rcb[0]->flags))) {\
 		bna_ib_coalescing_timer_set((_ccb)->i_dbell,	\
 			(_ccb)->rx_coalescing_timeo);		\
 		bna_ib_ack((_ccb)->i_dbell, 0);			\