Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:

 1) BPF debugger and asm tool by Daniel Borkmann.

 2) Speed up create/bind in AF_PACKET, also from Daniel Borkmann.

 3) Correct reciprocal_divide and update users, from Hannes Frederic
    Sowa and Daniel Borkmann.

 4) Currently we only have a "set" operation for the hw timestamp socket
    ioctl, add a "get" operation to match.  From Ben Hutchings.

 5) Add better trace events for debugging driver datapath problems, also
    from Ben Hutchings.

 6) Implement auto corking in TCP, from Eric Dumazet.  Basically, if we
    have a small send and a previous packet is already in the qdisc or
    device queue, defer until TX completion or we get more data.

 7) Allow userspace to manage ipv6 temporary addresses, from Jiri Pirko.

 8) Add a qdisc bypass option for AF_PACKET sockets, from Daniel
    Borkmann.

 9) Share IP header compression code between Bluetooth and IEEE802154
    layers, from Jukka Rissanen.

10) Fix ipv6 router reachability probing, from Jiri Benc.

11) Allow packets to be captured on macvtap devices, from Vlad Yasevich.

12) Support tunneling in GRO layer, from Jerry Chu.

13) Allow bonding to be configured fully using netlink, from Scott
    Feldman.

14) Allow AF_PACKET users to obtain the VLAN TPID, just like they can
    already get the TCI.  From Atzm Watanabe.

15) New "Heavy Hitter" qdisc, from Terry Lam.

16) Significantly improve the IPSEC support in pktgen, from Fan Du.

17) Allow ipv4 tunnels to cache routes, just like sockets.  From Tom
    Herbert.

18) Add Proportional Integral Enhanced packet scheduler, from Vijay
    Subramanian.

19) Allow openvswitch to mmap'd netlink, from Thomas Graf.

20) Key TCP metrics blobs also by source address, not just destination
    address.  From Christoph Paasch.

21) Support 10G in generic phylib.  From Andy Fleming.

22) Try to short-circuit GRO flow compares using device provided RX
    hash, if provided.  From Tom Herbert.

The wireless and netfilter folks have been busy little bees too.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2064 commits)
  net/cxgb4: Fix referencing freed adapter
  ipv6: reallocate addrconf router for ipv6 address when lo device up
  fib_frontend: fix possible NULL pointer dereference
  rtnetlink: remove IFLA_BOND_SLAVE definition
  rtnetlink: remove check for fill_slave_info in rtnl_have_link_slave_info
  qlcnic: update version to 5.3.55
  qlcnic: Enhance logic to calculate msix vectors.
  qlcnic: Refactor interrupt coalescing code for all adapters.
  qlcnic: Update poll controller code path
  qlcnic: Interrupt code cleanup
  qlcnic: Enhance Tx timeout debugging.
  qlcnic: Use bool for rx_mac_learn.
  bonding: fix u64 division
  rtnetlink: add missing IFLA_BOND_AD_INFO_UNSPEC
  sfc: Use the correct maximum TX DMA ring size for SFC9100
  Add Shradha Shah as the sfc driver maintainer.
  net/vxlan: Share RX skb de-marking and checksum checks with ovs
  tulip: cleanup by using ARRAY_SIZE()
  ip_tunnel: clear IPCB in ip_tunnel_xmit() in case dst_link_failure() is called
  net/cxgb4: Don't retrieve stats during recovery
  ...

4 files changed, 133 insertions, 451 deletions

diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index c47794b9d42..4c76bcb9a87 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -143,12 +143,11 @@ struct xenvif {
 	char rx_irq_name[IFNAMSIZ+4]; /* DEVNAME-rx */
 	struct xen_netif_rx_back_ring rx;
 	struct sk_buff_head rx_queue;
-
-	/* Allow xenvif_start_xmit() to peek ahead in the rx request
-	 * ring.  This is a prediction of what rx_req_cons will be
-	 * once all queued skbs are put on the ring.
+	bool rx_queue_stopped;
+	/* Set when the RX interrupt is triggered by the frontend.
+	 * The worker thread may need to wake the queue.
 	 */
-	RING_IDX rx_req_cons_peek;
+	bool rx_event;
 
 	/* This array is allocated seperately as it is large */
 	struct gnttab_copy *grant_copy_op;
@@ -205,8 +204,6 @@ void xenvif_xenbus_fini(void);
 
 int xenvif_schedulable(struct xenvif *vif);
 
-int xenvif_rx_ring_full(struct xenvif *vif);
-
 int xenvif_must_stop_queue(struct xenvif *vif);
 
 /* (Un)Map communication rings. */
@@ -218,21 +215,20 @@ int xenvif_map_frontend_rings(struct xenvif *vif,
 /* Check for SKBs from frontend and schedule backend processing */
 void xenvif_check_rx_xenvif(struct xenvif *vif);
 
-/* Queue an SKB for transmission to the frontend */
-void xenvif_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb);
-/* Notify xenvif that ring now has space to send an skb to the frontend */
-void xenvif_notify_tx_completion(struct xenvif *vif);
-
 /* Prevent the device from generating any further traffic. */
 void xenvif_carrier_off(struct xenvif *vif);
 
-/* Returns number of ring slots required to send an skb to the frontend */
-unsigned int xenvif_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
-
 int xenvif_tx_action(struct xenvif *vif, int budget);
-void xenvif_rx_action(struct xenvif *vif);
 
 int xenvif_kthread(void *data);
+void xenvif_kick_thread(struct xenvif *vif);
+
+/* Determine whether the needed number of slots (req) are available,
+ * and set req_event if not.
+ */
+bool xenvif_rx_ring_slots_available(struct xenvif *vif, int needed);
+
+void xenvif_stop_queue(struct xenvif *vif);
 
 extern bool separate_tx_rx_irq;
 
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index fff8cddfed8..b9de31ea7fc 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -47,11 +47,6 @@ int xenvif_schedulable(struct xenvif *vif)
 	return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
 }
 
-static int xenvif_rx_schedulable(struct xenvif *vif)
-{
-	return xenvif_schedulable(vif) && !xenvif_rx_ring_full(vif);
-}
-
 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
 {
 	struct xenvif *vif = dev_id;
@@ -105,8 +100,8 @@ static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
 {
 	struct xenvif *vif = dev_id;
 
-	if (xenvif_rx_schedulable(vif))
-		netif_wake_queue(vif->dev);
+	vif->rx_event = true;
+	xenvif_kick_thread(vif);
 
 	return IRQ_HANDLED;
 }
@@ -122,24 +117,35 @@ static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct xenvif *vif = netdev_priv(dev);
+	int min_slots_needed;
 
 	BUG_ON(skb->dev != dev);
 
 	/* Drop the packet if vif is not ready */
-	if (vif->task == NULL)
+	if (vif->task == NULL || !xenvif_schedulable(vif))
 		goto drop;
 
-	/* Drop the packet if the target domain has no receive buffers. */
-	if (!xenvif_rx_schedulable(vif))
-		goto drop;
+	/* At best we'll need one slot for the header and one for each
+	 * frag.
+	 */
+	min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;
 
-	/* Reserve ring slots for the worst-case number of fragments. */
-	vif->rx_req_cons_peek += xenvif_count_skb_slots(vif, skb);
+	/* If the skb is GSO then we'll also need an extra slot for the
+	 * metadata.
+	 */
+	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
+	    skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+		min_slots_needed++;
 
-	if (vif->can_queue && xenvif_must_stop_queue(vif))
-		netif_stop_queue(dev);
+	/* If the skb can't possibly fit in the remaining slots
+	 * then turn off the queue to give the ring a chance to
+	 * drain.
+	 */
+	if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
+		xenvif_stop_queue(vif);
 
-	xenvif_queue_tx_skb(vif, skb);
+	skb_queue_tail(&vif->rx_queue, skb);
+	xenvif_kick_thread(vif);
 
 	return NETDEV_TX_OK;
 
@@ -149,12 +155,6 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-void xenvif_notify_tx_completion(struct xenvif *vif)
-{
-	if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
-		netif_wake_queue(vif->dev);
-}
-
 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
 {
 	struct xenvif *vif = netdev_priv(dev);
@@ -388,6 +388,8 @@ int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
 	if (err < 0)
 		goto err;
 
+	init_waitqueue_head(&vif->wq);
+
 	if (tx_evtchn == rx_evtchn) {
 		/* feature-split-event-channels == 0 */
 		err = bind_interdomain_evtchn_to_irqhandler(
@@ -420,7 +422,6 @@ int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
 		disable_irq(vif->rx_irq);
 	}
 
-	init_waitqueue_head(&vif->wq);
 	task = kthread_create(xenvif_kthread,
 			      (void *)vif, "%s", vif->dev->name);
 	if (IS_ERR(task)) {
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 78425554a53..6b62c3eb8e1 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -39,7 +39,6 @@
 #include <linux/udp.h>
 
 #include <net/tcp.h>
-#include <net/ip6_checksum.h>
 
 #include <xen/xen.h>
 #include <xen/events.h>
@@ -138,36 +137,26 @@ static inline pending_ring_idx_t nr_pending_reqs(struct xenvif *vif)
 		vif->pending_prod + vif->pending_cons;
 }
 
-static int max_required_rx_slots(struct xenvif *vif)
+bool xenvif_rx_ring_slots_available(struct xenvif *vif, int needed)
 {
-	int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE);
+	RING_IDX prod, cons;
 
-	/* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */
-	if (vif->can_sg || vif->gso_mask || vif->gso_prefix_mask)
-		max += MAX_SKB_FRAGS + 1; /* extra_info + frags */
-
-	return max;
-}
+	do {
+		prod = vif->rx.sring->req_prod;
+		cons = vif->rx.req_cons;
 
-int xenvif_rx_ring_full(struct xenvif *vif)
-{
-	RING_IDX peek   = vif->rx_req_cons_peek;
-	RING_IDX needed = max_required_rx_slots(vif);
+		if (prod - cons >= needed)
+			return true;
 
-	return ((vif->rx.sring->req_prod - peek) < needed) ||
-	       ((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed);
-}
+		vif->rx.sring->req_event = prod + 1;
 
-int xenvif_must_stop_queue(struct xenvif *vif)
-{
-	if (!xenvif_rx_ring_full(vif))
-		return 0;
-
-	vif->rx.sring->req_event = vif->rx_req_cons_peek +
-		max_required_rx_slots(vif);
-	mb(); /* request notification /then/ check the queue */
+		/* Make sure event is visible before we check prod
+		 * again.
+		 */
+		mb();
+	} while (vif->rx.sring->req_prod != prod);
 
-	return xenvif_rx_ring_full(vif);
+	return false;
 }
 
 /*
@@ -210,93 +199,6 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
 	return false;
 }
 
-struct xenvif_count_slot_state {
-	unsigned long copy_off;
-	bool head;
-};
-
-unsigned int xenvif_count_frag_slots(struct xenvif *vif,
-				     unsigned long offset, unsigned long size,
-				     struct xenvif_count_slot_state *state)
-{
-	unsigned count = 0;
-
-	offset &= ~PAGE_MASK;
-
-	while (size > 0) {
-		unsigned long bytes;
-
-		bytes = PAGE_SIZE - offset;
-
-		if (bytes > size)
-			bytes = size;
-
-		if (start_new_rx_buffer(state->copy_off, bytes, state->head)) {
-			count++;
-			state->copy_off = 0;
-		}
-
-		if (state->copy_off + bytes > MAX_BUFFER_OFFSET)
-			bytes = MAX_BUFFER_OFFSET - state->copy_off;
-
-		state->copy_off += bytes;
-
-		offset += bytes;
-		size -= bytes;
-
-		if (offset == PAGE_SIZE)
-			offset = 0;
-
-		state->head = false;
-	}
-
-	return count;
-}
-
-/*
- * Figure out how many ring slots we're going to need to send @skb to
- * the guest. This function is essentially a dry run of
- * xenvif_gop_frag_copy.
- */
-unsigned int xenvif_count_skb_slots(struct xenvif *vif, struct sk_buff *skb)
-{
-	struct xenvif_count_slot_state state;
-	unsigned int count;
-	unsigned char *data;
-	unsigned i;
-
-	state.head = true;
-	state.copy_off = 0;
-
-	/* Slot for the first (partial) page of data. */
-	count = 1;
-
-	/* Need a slot for the GSO prefix for GSO extra data? */
-	if (skb_shinfo(skb)->gso_size)
-		count++;
-
-	data = skb->data;
-	while (data < skb_tail_pointer(skb)) {
-		unsigned long offset = offset_in_page(data);
-		unsigned long size = PAGE_SIZE - offset;
-
-		if (data + size > skb_tail_pointer(skb))
-			size = skb_tail_pointer(skb) - data;
-
-		count += xenvif_count_frag_slots(vif, offset, size, &state);
-
-		data += size;
-	}
-
-	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-		unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
-		unsigned long offset = skb_shinfo(skb)->frags[i].page_offset;
-
-		count += xenvif_count_frag_slots(vif, offset, size, &state);
-	}
-	return count;
-}
-
 struct netrx_pending_operations {
 	unsigned copy_prod, copy_cons;
 	unsigned meta_prod, meta_cons;
@@ -557,12 +459,12 @@ struct skb_cb_overlay {
 	int meta_slots_used;
 };
 
-static void xenvif_kick_thread(struct xenvif *vif)
+void xenvif_kick_thread(struct xenvif *vif)
 {
 	wake_up(&vif->wq);
 }
 
-void xenvif_rx_action(struct xenvif *vif)
+static void xenvif_rx_action(struct xenvif *vif)
 {
 	s8 status;
 	u16 flags;
@@ -571,11 +473,10 @@ void xenvif_rx_action(struct xenvif *vif)
 	struct sk_buff *skb;
 	LIST_HEAD(notify);
 	int ret;
-	int nr_frags;
-	int count;
 	unsigned long offset;
 	struct skb_cb_overlay *sco;
-	int need_to_notify = 0;
+	bool need_to_notify = false;
+	bool ring_full = false;
 
 	struct netrx_pending_operations npo = {
 		.copy  = vif->grant_copy_op,
@@ -584,29 +485,47 @@ void xenvif_rx_action(struct xenvif *vif)
 
 	skb_queue_head_init(&rxq);
 
-	count = 0;
-
 	while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) {
-		vif = netdev_priv(skb->dev);
-		nr_frags = skb_shinfo(skb)->nr_frags;
+		int max_slots_needed;
+		int i;
+
+		/* We need a cheap worse case estimate for the number of
+		 * slots we'll use.
+		 */
+
+		max_slots_needed = DIV_ROUND_UP(offset_in_page(skb->data) +
+						skb_headlen(skb),
+						PAGE_SIZE);
+		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+			unsigned int size;
+			size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
+			max_slots_needed += DIV_ROUND_UP(size, PAGE_SIZE);
+		}
+		if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
+		    skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
+			max_slots_needed++;
+
+		/* If the skb may not fit then bail out now */
+		if (!xenvif_rx_ring_slots_available(vif, max_slots_needed)) {
+			skb_queue_head(&vif->rx_queue, skb);
+			need_to_notify = true;
+			ring_full = true;
+			break;
+		}
 
 		sco = (struct skb_cb_overlay *)skb->cb;
 		sco->meta_slots_used = xenvif_gop_skb(skb, &npo);
-
-		count += nr_frags + 1;
+		BUG_ON(sco->meta_slots_used > max_slots_needed);
 
 		__skb_queue_tail(&rxq, skb);
-
-		/* Filled the batch queue? */
-		/* XXX FIXME: RX path dependent on MAX_SKB_FRAGS */
-		if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE)
-			break;
 	}
 
 	BUG_ON(npo.meta_prod > ARRAY_SIZE(vif->meta));
 
+	vif->rx_queue_stopped = !npo.copy_prod && ring_full;
+
 	if (!npo.copy_prod)
-		return;
+		goto done;
 
 	BUG_ON(npo.copy_prod > MAX_GRANT_COPY_OPS);
 	gnttab_batch_copy(vif->grant_copy_op, npo.copy_prod);
@@ -614,8 +533,6 @@ void xenvif_rx_action(struct xenvif *vif)
 	while ((skb = __skb_dequeue(&rxq)) != NULL) {
 		sco = (struct skb_cb_overlay *)skb->cb;
 
-		vif = netdev_priv(skb->dev);
-
 		if ((1 << vif->meta[npo.meta_cons].gso_type) &
 		    vif->gso_prefix_mask) {
 			resp = RING_GET_RESPONSE(&vif->rx,
@@ -678,28 +595,15 @@ void xenvif_rx_action(struct xenvif *vif)
 
 		RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret);
 
-		if (ret)
-			need_to_notify = 1;
-
-		xenvif_notify_tx_completion(vif);
+		need_to_notify |= !!ret;
 
 		npo.meta_cons += sco->meta_slots_used;
 		dev_kfree_skb(skb);
 	}
 
+done:
 	if (need_to_notify)
 		notify_remote_via_irq(vif->rx_irq);
-
-	/* More work to do? */
-	if (!skb_queue_empty(&vif->rx_queue))
-		xenvif_kick_thread(vif);
-}
-
-void xenvif_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb)
-{
-	skb_queue_tail(&vif->rx_queue, skb);
-
-	xenvif_kick_thread(vif);
 }
 
 void xenvif_check_rx_xenvif(struct xenvif *vif)
@@ -1141,265 +1045,14 @@ static int xenvif_set_skb_gso(struct xenvif *vif,
 	}
 
 	skb_shinfo(skb)->gso_size = gso->u.gso.size;
-
-	/* Header must be checked, and gso_segs computed. */
-	skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
-	skb_shinfo(skb)->gso_segs = 0;
-
-	return 0;
-}
-
-static inline int maybe_pull_tail(struct sk_buff *skb, unsigned int len,
-				  unsigned int max)
-{
-	if (skb_headlen(skb) >= len)
-		return 0;
-
-	/* If we need to pullup then pullup to the max, so we
-	 * won't need to do it again.
-	 */
-	if (max > skb->len)
-		max = skb->len;
-
-	if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL)
-		return -ENOMEM;
-
-	if (skb_headlen(skb) < len)
-		return -EPROTO;
+	/* gso_segs will be calculated later */
 
 	return 0;
 }
 
-/* This value should be large enough to cover a tagged ethernet header plus
- * maximally sized IP and TCP or UDP headers.
- */
-#define MAX_IP_HDR_LEN 128
-
-static int checksum_setup_ip(struct xenvif *vif, struct sk_buff *skb,
-			     int recalculate_partial_csum)
-{
-	unsigned int off;
-	bool fragment;
-	int err;
-
-	fragment = false;
-
-	err = maybe_pull_tail(skb,
-			      sizeof(struct iphdr),
-			      MAX_IP_HDR_LEN);
-	if (err < 0)
-		goto out;
-
-	if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF))
-		fragment = true;
-
-	off = ip_hdrlen(skb);
-
-	err = -EPROTO;
-
-	if (fragment)
-		goto out;
-
-	switch (ip_hdr(skb)->protocol) {
-	case IPPROTO_TCP:
-		err = maybe_pull_tail(skb,
-				      off + sizeof(struct tcphdr),
-				      MAX_IP_HDR_LEN);
-		if (err < 0)
-			goto out;
-
-		if (!skb_partial_csum_set(skb, off,
-					  offsetof(struct tcphdr, check))) {
-			err = -EPROTO;
-			goto out;
-		}
-
-		if (recalculate_partial_csum)
-			tcp_hdr(skb)->check =
-				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
-						   ip_hdr(skb)->daddr,
-						   skb->len - off,
-						   IPPROTO_TCP, 0);
-		break;
-	case IPPROTO_UDP:
-		err = maybe_pull_tail(skb,
-				      off + sizeof(struct udphdr),
-				      MAX_IP_HDR_LEN);
-		if (err < 0)
-			goto out;
-
-		if (!skb_partial_csum_set(skb, off,
-					  offsetof(struct udphdr, check))) {
-			err = -EPROTO;
-			goto out;
-		}
-
-		if (recalculate_partial_csum)
-			udp_hdr(skb)->check =
-				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
-						   ip_hdr(skb)->daddr,
-						   skb->len - off,
-						   IPPROTO_UDP, 0);
-		break;
-	default:
-		goto out;
-	}
-
-	err = 0;
-
-out:
-	return err;
-}
-
-/* This value should be large enough to cover a tagged ethernet header plus
- * an IPv6 header, all options, and a maximal TCP or UDP header.
- */
-#define MAX_IPV6_HDR_LEN 256
-
-#define OPT_HDR(type, skb, off) \
-	(type *)(skb_network_header(skb) + (off))
-
-static int checksum_setup_ipv6(struct xenvif *vif, struct sk_buff *skb,
-			       int recalculate_partial_csum)
-{
-	int err;
-	u8 nexthdr;
-	unsigned int off;
-	unsigned int len;
-	bool fragment;
-	bool done;
-
-	fragment = false;
-	done = false;
-
-	off = sizeof(struct ipv6hdr);
-
-	err = maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN);
-	if (err < 0)
-		goto out;
-
-	nexthdr = ipv6_hdr(skb)->nexthdr;
-
-	len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len);
-	while (off <= len && !done) {
-		switch (nexthdr) {
-		case IPPROTO_DSTOPTS:
-		case IPPROTO_HOPOPTS:
-		case IPPROTO_ROUTING: {
-			struct ipv6_opt_hdr *hp;
-
-			err = maybe_pull_tail(skb,
-					      off +
-					      sizeof(struct ipv6_opt_hdr),
-					      MAX_IPV6_HDR_LEN);
-			if (err < 0)
-				goto out;
-
-			hp = OPT_HDR(struct ipv6_opt_hdr, skb, off);
-			nexthdr = hp->nexthdr;
-			off += ipv6_optlen(hp);
-			break;
-		}
-		case IPPROTO_AH: {
-			struct ip_auth_hdr *hp;
-
-			err = maybe_pull_tail(skb,
-					      off +
-					      sizeof(struct ip_auth_hdr),
-					      MAX_IPV6_HDR_LEN);
-			if (err < 0)
-				goto out;
-
-			hp = OPT_HDR(struct ip_auth_hdr, skb, off);
-			nexthdr = hp->nexthdr;
-			off += ipv6_authlen(hp);
-			break;
-		}
-		case IPPROTO_FRAGMENT: {
-			struct frag_hdr *hp;
-
-			err = maybe_pull_tail(skb,
-					      off +
-					      sizeof(struct frag_hdr),
-					      MAX_IPV6_HDR_LEN);
-			if (err < 0)
-				goto out;
-
-			hp = OPT_HDR(struct frag_hdr, skb, off);
-
-			if (hp->frag_off & htons(IP6_OFFSET | IP6_MF))
-				fragment = true;
-
-			nexthdr = hp->nexthdr;
-			off += sizeof(struct frag_hdr);
-			break;
-		}
-		default:
-			done = true;
-			break;
-		}
-	}
-
-	err = -EPROTO;
-
-	if (!done || fragment)
-		goto out;
-
-	switch (nexthdr) {
-	case IPPROTO_TCP:
-		err = maybe_pull_tail(skb,
-				      off + sizeof(struct tcphdr),
-				      MAX_IPV6_HDR_LEN);
-		if (err < 0)
-			goto out;
-
-		if (!skb_partial_csum_set(skb, off,
-					  offsetof(struct tcphdr, check))) {
-			err = -EPROTO;
-			goto out;
-		}
-
-		if (recalculate_partial_csum)
-			tcp_hdr(skb)->check =
-				~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
-						 &ipv6_hdr(skb)->daddr,
-						 skb->len - off,
-						 IPPROTO_TCP, 0);
-		break;
-	case IPPROTO_UDP:
-		err = maybe_pull_tail(skb,
-				      off + sizeof(struct udphdr),
-				      MAX_IPV6_HDR_LEN);
-		if (err < 0)
-			goto out;
-
-		if (!skb_partial_csum_set(skb, off,
-					  offsetof(struct udphdr, check))) {
-			err = -EPROTO;
-			goto out;
-		}
-
-		if (recalculate_partial_csum)
-			udp_hdr(skb)->check =
-				~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
-						 &ipv6_hdr(skb)->daddr,
-						 skb->len - off,
-						 IPPROTO_UDP, 0);
-		break;
-	default:
-		goto out;
-	}
-
-	err = 0;
-
-out:
-	return err;
-}
-
 static int checksum_setup(struct xenvif *vif, struct sk_buff *skb)
 {
-	int err = -EPROTO;
-	int recalculate_partial_csum = 0;
+	bool recalculate_partial_csum = false;
 
 	/* A GSO SKB must be CHECKSUM_PARTIAL. However some buggy
 	 * peers can fail to set NETRXF_csum_blank when sending a GSO
@@ -1409,19 +1062,14 @@ static int checksum_setup(struct xenvif *vif, struct sk_buff *skb)
 	if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) {
 		vif->rx_gso_checksum_fixup++;
 		skb->ip_summed = CHECKSUM_PARTIAL;
-		recalculate_partial_csum = 1;
+		recalculate_partial_csum = true;
 	}
 
 	/* A non-CHECKSUM_PARTIAL SKB does not require setup. */
 	if (skb->ip_summed != CHECKSUM_PARTIAL)
 		return 0;
 
-	if (skb->protocol == htons(ETH_P_IP))
-		err = checksum_setup_ip(vif, skb, recalculate_partial_csum);
-	else if (skb->protocol == htons(ETH_P_IPV6))
-		err = checksum_setup_ipv6(vif, skb, recalculate_partial_csum);
-
-	return err;
+	return skb_checksum_setup(skb, recalculate_partial_csum);
 }
 
 static bool tx_credit_exceeded(struct xenvif *vif, unsigned size)
@@ -1687,6 +1335,20 @@ static int xenvif_tx_submit(struct xenvif *vif)
 
 		skb_probe_transport_header(skb, 0);
 
+		/* If the packet is GSO then we will have just set up the
+		 * transport header offset in checksum_setup so it's now
+		 * straightforward to calculate gso_segs.
+		 */
+		if (skb_is_gso(skb)) {
+			int mss = skb_shinfo(skb)->gso_size;
+			int hdrlen = skb_transport_header(skb) -
+				skb_mac_header(skb) +
+				tcp_hdrlen(skb);
+
+			skb_shinfo(skb)->gso_segs =
+				DIV_ROUND_UP(skb->len - hdrlen, mss);
+		}
+
 		vif->dev->stats.rx_bytes += skb->len;
 		vif->dev->stats.rx_packets++;
 
@@ -1811,7 +1473,8 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif,
 
 static inline int rx_work_todo(struct xenvif *vif)
 {
-	return !skb_queue_empty(&vif->rx_queue);
+	return (!skb_queue_empty(&vif->rx_queue) && !vif->rx_queue_stopped) ||
+		vif->rx_event;
 }
 
 static inline int tx_work_todo(struct xenvif *vif)
@@ -1861,8 +1524,6 @@ int xenvif_map_frontend_rings(struct xenvif *vif,
 	rxs = (struct xen_netif_rx_sring *)addr;
 	BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE);
 
-	vif->rx_req_cons_peek = 0;
-
 	return 0;
 
 err:
@@ -1870,9 +1531,24 @@ err:
 	return err;
 }
 
+void xenvif_stop_queue(struct xenvif *vif)
+{
+	if (!vif->can_queue)
+		return;
+
+	netif_stop_queue(vif->dev);
+}
+
+static void xenvif_start_queue(struct xenvif *vif)
+{
+	if (xenvif_schedulable(vif))
+		netif_wake_queue(vif->dev);
+}
+
 int xenvif_kthread(void *data)
 {
 	struct xenvif *vif = data;
+	struct sk_buff *skb;
 
 	while (!kthread_should_stop()) {
 		wait_event_interruptible(vif->wq,
@@ -1881,12 +1557,22 @@ int xenvif_kthread(void *data)
 		if (kthread_should_stop())
 			break;
 
-		if (rx_work_todo(vif))
+		if (!skb_queue_empty(&vif->rx_queue))
 			xenvif_rx_action(vif);
 
+		vif->rx_event = false;
+
+		if (skb_queue_empty(&vif->rx_queue) &&
+		    netif_queue_stopped(vif->dev))
+			xenvif_start_queue(vif);
+
 		cond_resched();
 	}
 
+	/* Bin any remaining skbs */
+	while ((skb = skb_dequeue(&vif->rx_queue)) != NULL)
+		dev_kfree_skb(skb);
+
 	return 0;
 }
 
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index f0358992b04..7a206cffb06 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -15,8 +15,7 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "common.h"