Commit 0ab05141 authored by Stephen Hemminger's avatar Stephen Hemminger Committed by David S. Miller
Browse files

hv_netvsc: rearrange start_xmit



Rearrange the transmit routine to eliminate goto's and unnecessary
boolean variables. Use standard functions to test for vlan tag.

Signed-off-by: default avatarStephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fd612602
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+51 −55
Original line number Diff line number Diff line
@@ -357,11 +357,8 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
	struct rndis_message *rndis_msg;
	struct rndis_packet *rndis_pkt;
	u32 rndis_msg_size;
	bool isvlan;
	bool linear = false;
	struct rndis_per_packet_info *ppi;
	struct ndis_tcp_ip_checksum_info *csum_info;
	struct ndis_tcp_lso_info *lso_info;
	int  hdr_offset;
	u32 net_trans_info;
	u32 hash;
@@ -376,22 +373,23 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
	 * more pages we try linearizing it.
	 */

check_size:
	skb_length = skb->len;
	num_data_pgs = netvsc_get_slots(skb) + 2;
	if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
		net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
				      num_data_pgs, skb->len);
		ret = -EFAULT;
		goto drop;
	} else if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {

	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
		if (skb_linearize(skb)) {
			net_alert_ratelimited("failed to linearize skb\n");
			ret = -ENOMEM;
			goto drop;
		}
		linear = true;
		goto check_size;

		num_data_pgs = netvsc_get_slots(skb) + 2;
		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
			net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
					      num_data_pgs, skb->len);
			ret = -EFAULT;
			goto drop;
		}
	}

	/*
@@ -418,8 +416,6 @@ check_size:

	memset(rndis_msg, 0, RNDIS_AND_PPI_SIZE);

	isvlan = skb->vlan_tci & VLAN_TAG_PRESENT;

	/* Add the rndis header */
	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
	rndis_msg->msg_len = packet->total_data_buflen;
@@ -438,7 +434,7 @@ check_size:
		*(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
	}

	if (isvlan) {
	if (skb_vlan_tag_present(skb)) {
		struct ndis_pkt_8021q_info *vlan;

		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
@@ -459,8 +455,37 @@ check_size:
	 * Setup the sendside checksum offload only if this is not a
	 * GSO packet.
	 */
	if (skb_is_gso(skb))
		goto do_lso;
	if (skb_is_gso(skb)) {
		struct ndis_tcp_lso_info *lso_info;

		rndis_msg_size += NDIS_LSO_PPI_SIZE;
		ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
				    TCP_LARGESEND_PKTINFO);

		lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
							ppi->ppi_offset);

		lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
		if (net_trans_info & (INFO_IPV4 << 16)) {
			lso_info->lso_v2_transmit.ip_version =
				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
			ip_hdr(skb)->tot_len = 0;
			ip_hdr(skb)->check = 0;
			tcp_hdr(skb)->check =
				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
						   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
		} else {
			lso_info->lso_v2_transmit.ip_version =
				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
			ipv6_hdr(skb)->payload_len = 0;
			tcp_hdr(skb)->check =
				~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
						 &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
		}
		lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
		lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
		goto do_send;
	}

	if ((skb->ip_summed == CHECKSUM_NONE) ||
	    (skb->ip_summed == CHECKSUM_UNNECESSARY))
@@ -507,35 +532,6 @@ check_size:

		csum_info->transmit.udp_checksum = 0;
	}
	goto do_send;

do_lso:
	rndis_msg_size += NDIS_LSO_PPI_SIZE;
	ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
			    TCP_LARGESEND_PKTINFO);

	lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
			ppi->ppi_offset);

	lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
	if (net_trans_info & (INFO_IPV4 << 16)) {
		lso_info->lso_v2_transmit.ip_version =
			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
		ip_hdr(skb)->tot_len = 0;
		ip_hdr(skb)->check = 0;
		tcp_hdr(skb)->check =
		~csum_tcpudp_magic(ip_hdr(skb)->saddr,
				   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
	} else {
		lso_info->lso_v2_transmit.ip_version =
			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
		ipv6_hdr(skb)->payload_len = 0;
		tcp_hdr(skb)->check =
		~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
				&ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
	}
	lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
	lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;

do_send:
	/* Start filling in the page buffers with the rndis hdr */
@@ -548,21 +544,21 @@ do_send:
	skb_tx_timestamp(skb);
	ret = netvsc_send(net_device_ctx->device_ctx, packet,
			  rndis_msg, &pb, skb);

drop:
	if (ret == 0) {
	if (likely(ret == 0)) {
		u64_stats_update_begin(&tx_stats->syncp);
		tx_stats->packets++;
		tx_stats->bytes += skb_length;
		u64_stats_update_end(&tx_stats->syncp);
	} else {
		if (ret != -EAGAIN) {
		return NETDEV_TX_OK;
	}
	if (ret == -EAGAIN)
		return NETDEV_TX_BUSY;

drop:
	dev_kfree_skb_any(skb);
	net->stats.tx_dropped++;
		}
	}

	return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
	return NETDEV_TX_OK;
}

/*