ldmvsw: Split sunvnet driver into common code

  Split sunvnet.c into sunvnet.c and sunvnet_common.c.

  Details:

  Since the sunvnet and ldmvsw drivers will both use common sunvnet code,
  move the functions (and support functions) anticipated to be common code
  from sunvnet.c to sunvnet_common.c. Similarly, sunvnet.h was renamed to
  sunvnet_common.h. The sunvnet_common.c code will be compiled into the
  kernel and act as a library of functions that are linked by either
  (or both) drivers when loaded.

  Function names for external functions in sunvnet_common.c (to be
  called by both the sunvnet and ldmvsw drivers) were tagged with a "_common"
  suffix to clearly designate them as common functions.

  No functional changes as of yet... just moved code verbatim to the new
  sunvnet_common.c/h files.

  Makefile/Kconfig support added to build sunvnet_common.c file. The code
  is included in the kernel if SUN_LDOMS is defined/selected.

  NOTE - per the SubmittingPatches documentation, since the code was just
  moved from one file another, the code was NOT checkpatch'd in this commit
  to aid in review.

  Signed-off-by: Aaron Young <aaron.young@oracle.com>
  Signed-off-by: Rashmi Narasimhan <rashmi.narasimhan@oracle.com>
  Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
  Reviewed-by: Alexandre Chartre <Alexandre.Chartre@oracle.com>

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 1816 insertions, 1743 deletions

diff --git a/drivers/net/ethernet/sun/Kconfig b/drivers/net/ethernet/sun/Kconfig
index dee94b67638c..aa58c11ea6db 100644
--- a/drivers/net/ethernet/sun/Kconfig
+++ b/drivers/net/ethernet/sun/Kconfig
@@ -69,6 +69,11 @@ config CASSINI
 	  Support for the Sun Cassini chip, aka Sun GigaSwift Ethernet. See also
 	  <http://docs.oracle.com/cd/E19113-01/giga.ether.pci/817-4341-10/817-4341-10.pdf>.
 
+config SUNVNET_COMMON
+	bool
+	depends on SUN_LDOMS
+	default y if SUN_LDOMS
+
 config SUNVNET
 	tristate "Sun Virtual Network support"
 	depends on SUN_LDOMS
diff --git a/drivers/net/ethernet/sun/Makefile b/drivers/net/ethernet/sun/Makefile
index 1e620ff88eba..7b622aa14c5b 100644
--- a/drivers/net/ethernet/sun/Makefile
+++ b/drivers/net/ethernet/sun/Makefile
@@ -7,5 +7,6 @@ obj-$(CONFIG_SUNQE) += sunqe.o
 obj-$(CONFIG_SUNBMAC) += sunbmac.o
 obj-$(CONFIG_SUNGEM) += sungem.o
 obj-$(CONFIG_CASSINI) += cassini.o
+obj-$(CONFIG_SUNVNET_COMMON) += sunvnet_common.o
 obj-$(CONFIG_SUNVNET) += sunvnet.o
 obj-$(CONFIG_NIU) += niu.o
diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c
index 942a95db2061..5b9113524188 100644
--- a/drivers/net/ethernet/sun/sunvnet.c
+++ b/drivers/net/ethernet/sun/sunvnet.c
@@ -17,8 +17,6 @@
 #include <linux/mutex.h>
 #include <linux/highmem.h>
 #include <linux/if_vlan.h>
-#define CREATE_TRACE_POINTS
-#include <trace/events/sunvnet.h>
 
 #if IS_ENABLED(CONFIG_IPV6)
 #include <linux/icmpv6.h>
@@ -31,7 +29,12 @@
 #include <asm/vio.h>
 #include <asm/ldc.h>
 
-#include "sunvnet.h"
+#include "sunvnet_common.h"
+
+/* length of time before we decide the hardware is borked,
+ * and dev->tx_timeout() should be called to fix the problem
+ */
+#define VNET_TX_TIMEOUT			(5 * HZ)
 
 #define DRV_MODULE_NAME		"sunvnet"
 #define DRV_MODULE_VERSION	"1.0"
@@ -44,16 +47,6 @@ MODULE_DESCRIPTION("Sun LDOM virtual network driver");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(DRV_MODULE_VERSION);
 
-#define	VNET_MAX_TXQS		16
-
-/* Heuristic for the number of times to exponentially backoff and
- * retry sending an LDC trigger when EAGAIN is encountered
- */
-#define	VNET_MAX_RETRIES	10
-
-static int __vnet_tx_trigger(struct vnet_port *port, u32 start);
-static void vnet_port_reset(struct vnet_port *port);
-
 /* Ordered from largest major to lowest */
 static struct vio_version vnet_versions[] = {
 	{ .major = 1, .minor = 8 },
@@ -62,1578 +55,6 @@ static struct vio_version vnet_versions[] = {
 	{ .major = 1, .minor = 0 },
 };
 
-static inline u32 vnet_tx_dring_avail(struct vio_dring_state *dr)
-{
-	return vio_dring_avail(dr, VNET_TX_RING_SIZE);
-}
-
-static int vnet_handle_unknown(struct vnet_port *port, void *arg)
-{
-	struct vio_msg_tag *pkt = arg;
-
-	pr_err("Received unknown msg [%02x:%02x:%04x:%08x]\n",
-	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
-	pr_err("Resetting connection\n");
-
-	ldc_disconnect(port->vio.lp);
-
-	return -ECONNRESET;
-}
-
-static int vnet_port_alloc_tx_ring(struct vnet_port *port);
-
-static int vnet_send_attr(struct vio_driver_state *vio)
-{
-	struct vnet_port *port = to_vnet_port(vio);
-	struct net_device *dev = port->vp->dev;
-	struct vio_net_attr_info pkt;
-	int framelen = ETH_FRAME_LEN;
-	int i, err;
-
-	err = vnet_port_alloc_tx_ring(to_vnet_port(vio));
-	if (err)
-		return err;
-
-	memset(&pkt, 0, sizeof(pkt));
-	pkt.tag.type = VIO_TYPE_CTRL;
-	pkt.tag.stype = VIO_SUBTYPE_INFO;
-	pkt.tag.stype_env = VIO_ATTR_INFO;
-	pkt.tag.sid = vio_send_sid(vio);
-	if (vio_version_before(vio, 1, 2))
-		pkt.xfer_mode = VIO_DRING_MODE;
-	else
-		pkt.xfer_mode = VIO_NEW_DRING_MODE;
-	pkt.addr_type = VNET_ADDR_ETHERMAC;
-	pkt.ack_freq = 0;
-	for (i = 0; i < 6; i++)
-		pkt.addr |= (u64)dev->dev_addr[i] << ((5 - i) * 8);
-	if (vio_version_after(vio, 1, 3)) {
-		if (port->rmtu) {
-			port->rmtu = min(VNET_MAXPACKET, port->rmtu);
-			pkt.mtu = port->rmtu;
-		} else {
-			port->rmtu = VNET_MAXPACKET;
-			pkt.mtu = port->rmtu;
-		}
-		if (vio_version_after_eq(vio, 1, 6))
-			pkt.options = VIO_TX_DRING;
-	} else if (vio_version_before(vio, 1, 3)) {
-		pkt.mtu = framelen;
-	} else { /* v1.3 */
-		pkt.mtu = framelen + VLAN_HLEN;
-	}
-
-	pkt.cflags = 0;
-	if (vio_version_after_eq(vio, 1, 7) && port->tso) {
-		pkt.cflags |= VNET_LSO_IPV4_CAPAB;
-		if (!port->tsolen)
-			port->tsolen = VNET_MAXTSO;
-		pkt.ipv4_lso_maxlen = port->tsolen;
-	}
-
-	pkt.plnk_updt = PHYSLINK_UPDATE_NONE;
-
-	viodbg(HS, "SEND NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
-	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
-	       "cflags[0x%04x] lso_max[%u]\n",
-	       pkt.xfer_mode, pkt.addr_type,
-	       (unsigned long long)pkt.addr,
-	       pkt.ack_freq, pkt.plnk_updt, pkt.options,
-	       (unsigned long long)pkt.mtu, pkt.cflags, pkt.ipv4_lso_maxlen);
-
-
-	return vio_ldc_send(vio, &pkt, sizeof(pkt));
-}
-
-static int handle_attr_info(struct vio_driver_state *vio,
-			    struct vio_net_attr_info *pkt)
-{
-	struct vnet_port *port = to_vnet_port(vio);
-	u64	localmtu;
-	u8	xfer_mode;
-
-	viodbg(HS, "GOT NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
-	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
-	       " (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
-	       pkt->xfer_mode, pkt->addr_type,
-	       (unsigned long long)pkt->addr,
-	       pkt->ack_freq, pkt->plnk_updt, pkt->options,
-	       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
-	       pkt->ipv4_lso_maxlen);
-
-	pkt->tag.sid = vio_send_sid(vio);
-
-	xfer_mode = pkt->xfer_mode;
-	/* for version < 1.2, VIO_DRING_MODE = 0x3 and no bitmask */
-	if (vio_version_before(vio, 1, 2) && xfer_mode == VIO_DRING_MODE)
-		xfer_mode = VIO_NEW_DRING_MODE;
-
-	/* MTU negotiation:
-	 *	< v1.3 - ETH_FRAME_LEN exactly
-	 *	> v1.3 - MIN(pkt.mtu, VNET_MAXPACKET, port->rmtu) and change
-	 *			pkt->mtu for ACK
-	 *	= v1.3 - ETH_FRAME_LEN + VLAN_HLEN exactly
-	 */
-	if (vio_version_before(vio, 1, 3)) {
-		localmtu = ETH_FRAME_LEN;
-	} else if (vio_version_after(vio, 1, 3)) {
-		localmtu = port->rmtu ? port->rmtu : VNET_MAXPACKET;
-		localmtu = min(pkt->mtu, localmtu);
-		pkt->mtu = localmtu;
-	} else { /* v1.3 */
-		localmtu = ETH_FRAME_LEN + VLAN_HLEN;
-	}
-	port->rmtu = localmtu;
-
-	/* LSO negotiation */
-	if (vio_version_after_eq(vio, 1, 7))
-		port->tso &= !!(pkt->cflags & VNET_LSO_IPV4_CAPAB);
-	else
-		port->tso = false;
-	if (port->tso) {
-		if (!port->tsolen)
-			port->tsolen = VNET_MAXTSO;
-		port->tsolen = min(port->tsolen, pkt->ipv4_lso_maxlen);
-		if (port->tsolen < VNET_MINTSO) {
-			port->tso = false;
-			port->tsolen = 0;
-			pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
-		}
-		pkt->ipv4_lso_maxlen = port->tsolen;
-	} else {
-		pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
-		pkt->ipv4_lso_maxlen = 0;
-	}
-
-	/* for version >= 1.6, ACK packet mode we support */
-	if (vio_version_after_eq(vio, 1, 6)) {
-		pkt->xfer_mode = VIO_NEW_DRING_MODE;
-		pkt->options = VIO_TX_DRING;
-	}
-
-	if (!(xfer_mode | VIO_NEW_DRING_MODE) ||
-	    pkt->addr_type != VNET_ADDR_ETHERMAC ||
-	    pkt->mtu != localmtu) {
-		viodbg(HS, "SEND NET ATTR NACK\n");
-
-		pkt->tag.stype = VIO_SUBTYPE_NACK;
-
-		(void) vio_ldc_send(vio, pkt, sizeof(*pkt));
-
-		return -ECONNRESET;
-	} else {
-		viodbg(HS, "SEND NET ATTR ACK xmode[0x%x] atype[0x%x] "
-		       "addr[%llx] ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] "
-		       "mtu[%llu] (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
-		       pkt->xfer_mode, pkt->addr_type,
-		       (unsigned long long)pkt->addr,
-		       pkt->ack_freq, pkt->plnk_updt, pkt->options,
-		       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
-		       pkt->ipv4_lso_maxlen);
-
-		pkt->tag.stype = VIO_SUBTYPE_ACK;
-
-		return vio_ldc_send(vio, pkt, sizeof(*pkt));
-	}
-
-}
-
-static int handle_attr_ack(struct vio_driver_state *vio,
-			   struct vio_net_attr_info *pkt)
-{
-	viodbg(HS, "GOT NET ATTR ACK\n");
-
-	return 0;
-}
-
-static int handle_attr_nack(struct vio_driver_state *vio,
-			    struct vio_net_attr_info *pkt)
-{
-	viodbg(HS, "GOT NET ATTR NACK\n");
-
-	return -ECONNRESET;
-}
-
-static int vnet_handle_attr(struct vio_driver_state *vio, void *arg)
-{
-	struct vio_net_attr_info *pkt = arg;
-
-	switch (pkt->tag.stype) {
-	case VIO_SUBTYPE_INFO:
-		return handle_attr_info(vio, pkt);
-
-	case VIO_SUBTYPE_ACK:
-		return handle_attr_ack(vio, pkt);
-
-	case VIO_SUBTYPE_NACK:
-		return handle_attr_nack(vio, pkt);
-
-	default:
-		return -ECONNRESET;
-	}
-}
-
-static void vnet_handshake_complete(struct vio_driver_state *vio)
-{
-	struct vio_dring_state *dr;
-
-	dr = &vio->drings[VIO_DRIVER_RX_RING];
-	dr->snd_nxt = dr->rcv_nxt = 1;
-
-	dr = &vio->drings[VIO_DRIVER_TX_RING];
-	dr->snd_nxt = dr->rcv_nxt = 1;
-}
-
-/* The hypervisor interface that implements copying to/from imported
- * memory from another domain requires that copies are done to 8-byte
- * aligned buffers, and that the lengths of such copies are also 8-byte
- * multiples.
- *
- * So we align skb->data to an 8-byte multiple and pad-out the data
- * area so we can round the copy length up to the next multiple of
- * 8 for the copy.
- *
- * The transmitter puts the actual start of the packet 6 bytes into
- * the buffer it sends over, so that the IP headers after the ethernet
- * header are aligned properly.  These 6 bytes are not in the descriptor
- * length, they are simply implied.  This offset is represented using
- * the VNET_PACKET_SKIP macro.
- */
-static struct sk_buff *alloc_and_align_skb(struct net_device *dev,
-					   unsigned int len)
-{
-	struct sk_buff *skb = netdev_alloc_skb(dev, len+VNET_PACKET_SKIP+8+8);
-	unsigned long addr, off;
-
-	if (unlikely(!skb))
-		return NULL;
-
-	addr = (unsigned long) skb->data;
-	off = ((addr + 7UL) & ~7UL) - addr;
-	if (off)
-		skb_reserve(skb, off);
-
-	return skb;
-}
-
-static inline void vnet_fullcsum(struct sk_buff *skb)
-{
-	struct iphdr *iph = ip_hdr(skb);
-	int offset = skb_transport_offset(skb);
-
-	if (skb->protocol != htons(ETH_P_IP))
-		return;
-	if (iph->protocol != IPPROTO_TCP &&
-	    iph->protocol != IPPROTO_UDP)
-		return;
-	skb->ip_summed = CHECKSUM_NONE;
-	skb->csum_level = 1;
-	skb->csum = 0;
-	if (iph->protocol == IPPROTO_TCP) {
-		struct tcphdr *ptcp = tcp_hdr(skb);
-
-		ptcp->check = 0;
-		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
-		ptcp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
-						skb->len - offset, IPPROTO_TCP,
-						skb->csum);
-	} else if (iph->protocol == IPPROTO_UDP) {
-		struct udphdr *pudp = udp_hdr(skb);
-
-		pudp->check = 0;
-		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
-		pudp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
-						skb->len - offset, IPPROTO_UDP,
-						skb->csum);
-	}
-}
-
-static int vnet_rx_one(struct vnet_port *port, struct vio_net_desc *desc)
-{
-	struct net_device *dev = port->vp->dev;
-	unsigned int len = desc->size;
-	unsigned int copy_len;
-	struct sk_buff *skb;
-	int maxlen;
-	int err;
-
-	err = -EMSGSIZE;
-	if (port->tso && port->tsolen > port->rmtu)
-		maxlen = port->tsolen;
-	else
-		maxlen = port->rmtu;
-	if (unlikely(len < ETH_ZLEN || len > maxlen)) {
-		dev->stats.rx_length_errors++;
-		goto out_dropped;
-	}
-
-	skb = alloc_and_align_skb(dev, len);
-	err = -ENOMEM;
-	if (unlikely(!skb)) {
-		dev->stats.rx_missed_errors++;
-		goto out_dropped;
-	}
-
-	copy_len = (len + VNET_PACKET_SKIP + 7U) & ~7U;
-	skb_put(skb, copy_len);
-	err = ldc_copy(port->vio.lp, LDC_COPY_IN,
-		       skb->data, copy_len, 0,
-		       desc->cookies, desc->ncookies);
-	if (unlikely(err < 0)) {
-		dev->stats.rx_frame_errors++;
-		goto out_free_skb;
-	}
-
-	skb_pull(skb, VNET_PACKET_SKIP);
-	skb_trim(skb, len);
-	skb->protocol = eth_type_trans(skb, dev);
-
-	if (vio_version_after_eq(&port->vio, 1, 8)) {
-		struct vio_net_dext *dext = vio_net_ext(desc);
-
-		skb_reset_network_header(skb);
-
-		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM) {
-			if (skb->protocol == ETH_P_IP) {
-				struct iphdr *iph = ip_hdr(skb);
-
-				iph->check = 0;
-				ip_send_check(iph);
-			}
-		}
-		if ((dext->flags & VNET_PKT_HCK_FULLCKSUM) &&
-		    skb->ip_summed == CHECKSUM_NONE) {
-			if (skb->protocol == htons(ETH_P_IP)) {
-				struct iphdr *iph = ip_hdr(skb);
-				int ihl = iph->ihl * 4;
-
-				skb_reset_transport_header(skb);
-				skb_set_transport_header(skb, ihl);
-				vnet_fullcsum(skb);
-			}
-		}
-		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM_OK) {
-			skb->ip_summed = CHECKSUM_PARTIAL;
-			skb->csum_level = 0;
-			if (dext->flags & VNET_PKT_HCK_FULLCKSUM_OK)
-				skb->csum_level = 1;
-		}
-	}
-
-	skb->ip_summed = port->switch_port ? CHECKSUM_NONE : CHECKSUM_PARTIAL;
-
-	dev->stats.rx_packets++;
-	dev->stats.rx_bytes += len;
-	napi_gro_receive(&port->napi, skb);
-	return 0;
-
-out_free_skb:
-	kfree_skb(skb);
-
-out_dropped:
-	dev->stats.rx_dropped++;
-	return err;
-}
-
-static int vnet_send_ack(struct vnet_port *port, struct vio_dring_state *dr,
-			 u32 start, u32 end, u8 vio_dring_state)
-{
-	struct vio_dring_data hdr = {
-		.tag = {
-			.type		= VIO_TYPE_DATA,
-			.stype		= VIO_SUBTYPE_ACK,
-			.stype_env	= VIO_DRING_DATA,
-			.sid		= vio_send_sid(&port->vio),
-		},
-		.dring_ident		= dr->ident,
-		.start_idx		= start,
-		.end_idx		= end,
-		.state			= vio_dring_state,
-	};
-	int err, delay;
-	int retries = 0;
-
-	hdr.seq = dr->snd_nxt;
-	delay = 1;
-	do {
-		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
-		if (err > 0) {
-			dr->snd_nxt++;
-			break;
-		}
-		udelay(delay);
-		if ((delay <<= 1) > 128)
-			delay = 128;
-		if (retries++ > VNET_MAX_RETRIES) {
-			pr_info("ECONNRESET %x:%x:%x:%x:%x:%x\n",
-				port->raddr[0], port->raddr[1],
-				port->raddr[2], port->raddr[3],
-				port->raddr[4], port->raddr[5]);
-			break;
-		}
-	} while (err == -EAGAIN);
-
-	if (err <= 0 && vio_dring_state == VIO_DRING_STOPPED) {
-		port->stop_rx_idx = end;
-		port->stop_rx = true;
-	} else {
-		port->stop_rx_idx = 0;
-		port->stop_rx = false;
-	}
-
-	return err;
-}
-
-static struct vio_net_desc *get_rx_desc(struct vnet_port *port,
-					struct vio_dring_state *dr,
-					u32 index)
-{
-	struct vio_net_desc *desc = port->vio.desc_buf;
-	int err;
-
-	err = ldc_get_dring_entry(port->vio.lp, desc, dr->entry_size,
-				  (index * dr->entry_size),
-				  dr->cookies, dr->ncookies);
-	if (err < 0)
-		return ERR_PTR(err);
-
-	return desc;
-}
-
-static int put_rx_desc(struct vnet_port *port,
-		       struct vio_dring_state *dr,
-		       struct vio_net_desc *desc,
-		       u32 index)
-{
-	int err;
-
-	err = ldc_put_dring_entry(port->vio.lp, desc, dr->entry_size,
-				  (index * dr->entry_size),
-				  dr->cookies, dr->ncookies);
-	if (err < 0)
-		return err;
-
-	return 0;
-}
-
-static int vnet_walk_rx_one(struct vnet_port *port,
-			    struct vio_dring_state *dr,
-			    u32 index, int *needs_ack)
-{
-	struct vio_net_desc *desc = get_rx_desc(port, dr, index);
-	struct vio_driver_state *vio = &port->vio;
-	int err;
-
-	BUG_ON(desc == NULL);
-	if (IS_ERR(desc))
-		return PTR_ERR(desc);
-
-	if (desc->hdr.state != VIO_DESC_READY)
-		return 1;
-
-	dma_rmb();
-
-	viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
-	       desc->hdr.state, desc->hdr.ack,
-	       desc->size, desc->ncookies,
-	       desc->cookies[0].cookie_addr,
-	       desc->cookies[0].cookie_size);
-
-	err = vnet_rx_one(port, desc);
-	if (err == -ECONNRESET)
-		return err;
-	trace_vnet_rx_one(port->vio._local_sid, port->vio._peer_sid,
-			  index, desc->hdr.ack);
-	desc->hdr.state = VIO_DESC_DONE;
-	err = put_rx_desc(port, dr, desc, index);
-	if (err < 0)
-		return err;
-	*needs_ack = desc->hdr.ack;
-	return 0;
-}
-
-static int vnet_walk_rx(struct vnet_port *port, struct vio_dring_state *dr,
-			u32 start, u32 end, int *npkts, int budget)
-{
-	struct vio_driver_state *vio = &port->vio;
-	int ack_start = -1, ack_end = -1;
-	bool send_ack = true;
-
-	end = (end == (u32) -1) ? vio_dring_prev(dr, start)
-				: vio_dring_next(dr, end);
-
-	viodbg(DATA, "vnet_walk_rx start[%08x] end[%08x]\n", start, end);
-
-	while (start != end) {
-		int ack = 0, err = vnet_walk_rx_one(port, dr, start, &ack);
-		if (err == -ECONNRESET)
-			return err;
-		if (err != 0)
-			break;
-		(*npkts)++;
-		if (ack_start == -1)
-			ack_start = start;
-		ack_end = start;
-		start = vio_dring_next(dr, start);
-		if (ack && start != end) {
-			err = vnet_send_ack(port, dr, ack_start, ack_end,
-					    VIO_DRING_ACTIVE);
-			if (err == -ECONNRESET)
-				return err;
-			ack_start = -1;
-		}
-		if ((*npkts) >= budget) {
-			send_ack = false;
-			break;
-		}
-	}
-	if (unlikely(ack_start == -1))
-		ack_start = ack_end = vio_dring_prev(dr, start);
-	if (send_ack) {
-		port->napi_resume = false;
-		trace_vnet_tx_send_stopped_ack(port->vio._local_sid,
-					       port->vio._peer_sid,
-					       ack_end, *npkts);
-		return vnet_send_ack(port, dr, ack_start, ack_end,
-				     VIO_DRING_STOPPED);
-	} else  {
-		trace_vnet_tx_defer_stopped_ack(port->vio._local_sid,
-						port->vio._peer_sid,
-						ack_end, *npkts);
-		port->napi_resume = true;
-		port->napi_stop_idx = ack_end;
-		return 1;
-	}
-}
-
-static int vnet_rx(struct vnet_port *port, void *msgbuf, int *npkts,
-		   int budget)
-{
-	struct vio_dring_data *pkt = msgbuf;
-	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_RX_RING];
-	struct vio_driver_state *vio = &port->vio;
-
-	viodbg(DATA, "vnet_rx stype_env[%04x] seq[%016llx] rcv_nxt[%016llx]\n",
-	       pkt->tag.stype_env, pkt->seq, dr->rcv_nxt);
-
-	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
-		return 0;
-	if (unlikely(pkt->seq != dr->rcv_nxt)) {
-		pr_err("RX out of sequence seq[0x%llx] rcv_nxt[0x%llx]\n",
-		       pkt->seq, dr->rcv_nxt);
-		return 0;
-	}
-
-	if (!port->napi_resume)
-		dr->rcv_nxt++;
-
-	/* XXX Validate pkt->start_idx and pkt->end_idx XXX */
-
-	return vnet_walk_rx(port, dr, pkt->start_idx, pkt->end_idx,
-			    npkts, budget);
-}
-
-static int idx_is_pending(struct vio_dring_state *dr, u32 end)
-{
-	u32 idx = dr->cons;
-	int found = 0;
-
-	while (idx != dr->prod) {
-		if (idx == end) {
-			found = 1;
-			break;
-		}
-		idx = vio_dring_next(dr, idx);
-	}
-	return found;
-}
-
-static int vnet_ack(struct vnet_port *port, void *msgbuf)
-{
-	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-	struct vio_dring_data *pkt = msgbuf;
-	struct net_device *dev;
-	struct vnet *vp;
-	u32 end;
-	struct vio_net_desc *desc;
-	struct netdev_queue *txq;
-
-	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
-		return 0;
-
-	end = pkt->end_idx;
-	vp = port->vp;
-	dev = vp->dev;
-	netif_tx_lock(dev);
-	if (unlikely(!idx_is_pending(dr, end))) {
-		netif_tx_unlock(dev);
-		return 0;
-	}
-
-	/* sync for race conditions with vnet_start_xmit() and tell xmit it
-	 * is time to send a trigger.
-	 */
-	trace_vnet_rx_stopped_ack(port->vio._local_sid,
-				  port->vio._peer_sid, end);
-	dr->cons = vio_dring_next(dr, end);
-	desc = vio_dring_entry(dr, dr->cons);
-	if (desc->hdr.state == VIO_DESC_READY && !port->start_cons) {
-		/* vnet_start_xmit() just populated this dring but missed
-		 * sending the "start" LDC message to the consumer.
-		 * Send a "start" trigger on its behalf.
-		 */
-		if (__vnet_tx_trigger(port, dr->cons) > 0)
-			port->start_cons = false;
-		else
-			port->start_cons = true;
-	} else {
-		port->start_cons = true;
-	}
-	netif_tx_unlock(dev);
-
-	txq = netdev_get_tx_queue(dev, port->q_index);
-	if (unlikely(netif_tx_queue_stopped(txq) &&
-		     vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr)))
-		return 1;
-
-	return 0;
-}
-
-static int vnet_nack(struct vnet_port *port, void *msgbuf)
-{
-	/* XXX just reset or similar XXX */
-	return 0;
-}
-
-static int handle_mcast(struct vnet_port *port, void *msgbuf)
-{
-	struct vio_net_mcast_info *pkt = msgbuf;
-
-	if (pkt->tag.stype != VIO_SUBTYPE_ACK)
-		pr_err("%s: Got unexpected MCAST reply [%02x:%02x:%04x:%08x]\n",
-		       port->vp->dev->name,
-		       pkt->tag.type,
-		       pkt->tag.stype,
-		       pkt->tag.stype_env,
-		       pkt->tag.sid);
-
-	return 0;
-}
-
-/* Got back a STOPPED LDC message on port. If the queue is stopped,
- * wake it up so that we'll send out another START message at the
- * next TX.
- */
-static void maybe_tx_wakeup(struct vnet_port *port)
-{
-	struct netdev_queue *txq;
-
-	txq = netdev_get_tx_queue(port->vp->dev, port->q_index);
-	__netif_tx_lock(txq, smp_processor_id());
-	if (likely(netif_tx_queue_stopped(txq))) {
-		struct vio_dring_state *dr;
-
-		dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-		netif_tx_wake_queue(txq);
-	}
-	__netif_tx_unlock(txq);
-}
-
-static inline bool port_is_up(struct vnet_port *vnet)
-{
-	struct vio_driver_state *vio = &vnet->vio;
-
-	return !!(vio->hs_state & VIO_HS_COMPLETE);
-}
-
-static int vnet_event_napi(struct vnet_port *port, int budget)
-{
-	struct vio_driver_state *vio = &port->vio;
-	int tx_wakeup, err;
-	int npkts = 0;
-	int event = (port->rx_event & LDC_EVENT_RESET);
-
-ldc_ctrl:
-	if (unlikely(event == LDC_EVENT_RESET ||
-		     event == LDC_EVENT_UP)) {
-		vio_link_state_change(vio, event);
-
-		if (event == LDC_EVENT_RESET) {
-			vnet_port_reset(port);
-			vio_port_up(vio);
-		}
-		port->rx_event = 0;
-		return 0;
-	}
-	/* We may have multiple LDC events in rx_event. Unroll send_events() */
-	event = (port->rx_event & LDC_EVENT_UP);
-	port->rx_event &= ~(LDC_EVENT_RESET|LDC_EVENT_UP);
-	if (event == LDC_EVENT_UP)
-		goto ldc_ctrl;
-	event = port->rx_event;
-	if (!(event & LDC_EVENT_DATA_READY))
-		return 0;
-
-	/* we dont expect any other bits than RESET, UP, DATA_READY */
-	BUG_ON(event != LDC_EVENT_DATA_READY);
-
-	tx_wakeup = err = 0;
-	while (1) {
-		union {
-			struct vio_msg_tag tag;
-			u64 raw[8];
-		} msgbuf;
-
-		if (port->napi_resume) {
-			struct vio_dring_data *pkt =
-				(struct vio_dring_data *)&msgbuf;
-			struct vio_dring_state *dr =
-				&port->vio.drings[VIO_DRIVER_RX_RING];
-
-			pkt->tag.type = VIO_TYPE_DATA;
-			pkt->tag.stype = VIO_SUBTYPE_INFO;
-			pkt->tag.stype_env = VIO_DRING_DATA;
-			pkt->seq = dr->rcv_nxt;
-			pkt->start_idx = vio_dring_next(dr, port->napi_stop_idx);
-			pkt->end_idx = -1;
-			goto napi_resume;
-		}
-		err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
-		if (unlikely(err < 0)) {
-			if (err == -ECONNRESET)
-				vio_conn_reset(vio);
-			break;
-		}
-		if (err == 0)
-			break;
-		viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
-		       msgbuf.tag.type,
-		       msgbuf.tag.stype,
-		       msgbuf.tag.stype_env,
-		       msgbuf.tag.sid);
-		err = vio_validate_sid(vio, &msgbuf.tag);
-		if (err < 0)
-			break;
-napi_resume:
-		if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
-			if (msgbuf.tag.stype == VIO_SUBTYPE_INFO) {
-				if (!port_is_up(port)) {
-					/* failures like handshake_failure()
-					 * may have cleaned up dring, but
-					 * NAPI polling may bring us here.
-					 */
-					err = -ECONNRESET;
-					break;
-				}
-				err = vnet_rx(port, &msgbuf, &npkts, budget);
-				if (npkts >= budget)
-					break;
-				if (npkts == 0)
-					break;
-			} else if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) {
-				err = vnet_ack(port, &msgbuf);
-				if (err > 0)
-					tx_wakeup |= err;
-			} else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) {
-				err = vnet_nack(port, &msgbuf);
-			}
-		} else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
-			if (msgbuf.tag.stype_env == VNET_MCAST_INFO)
-				err = handle_mcast(port, &msgbuf);
-			else
-				err = vio_control_pkt_engine(vio, &msgbuf);
-			if (err)
-				break;
-		} else {
-			err = vnet_handle_unknown(port, &msgbuf);
-		}
-		if (err == -ECONNRESET)
-			break;
-	}
-	if (unlikely(tx_wakeup && err != -ECONNRESET))
-		maybe_tx_wakeup(port);
-	return npkts;
-}
-
-static int vnet_poll(struct napi_struct *napi, int budget)
-{
-	struct vnet_port *port = container_of(napi, struct vnet_port, napi);
-	struct vio_driver_state *vio = &port->vio;
-	int processed = vnet_event_napi(port, budget);
-
-	if (processed < budget) {
-		napi_complete(napi);
-		port->rx_event &= ~LDC_EVENT_DATA_READY;
-		vio_set_intr(vio->vdev->rx_ino, HV_INTR_ENABLED);
-	}
-	return processed;
-}
-
-static void vnet_event(void *arg, int event)
-{
-	struct vnet_port *port = arg;
-	struct vio_driver_state *vio = &port->vio;
-
-	port->rx_event |= event;
-	vio_set_intr(vio->vdev->rx_ino, HV_INTR_DISABLED);
-	napi_schedule(&port->napi);
-
-}
-
-static int __vnet_tx_trigger(struct vnet_port *port, u32 start)
-{
-	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-	struct vio_dring_data hdr = {
-		.tag = {
-			.type		= VIO_TYPE_DATA,
-			.stype		= VIO_SUBTYPE_INFO,
-			.stype_env	= VIO_DRING_DATA,
-			.sid		= vio_send_sid(&port->vio),
-		},
-		.dring_ident		= dr->ident,
-		.start_idx		= start,
-		.end_idx		= (u32) -1,
-	};
-	int err, delay;
-	int retries = 0;
-
-	if (port->stop_rx) {
-		trace_vnet_tx_pending_stopped_ack(port->vio._local_sid,
-						  port->vio._peer_sid,
-						  port->stop_rx_idx, -1);
-		err = vnet_send_ack(port,
-				    &port->vio.drings[VIO_DRIVER_RX_RING],
-				    port->stop_rx_idx, -1,
-				    VIO_DRING_STOPPED);
-		if (err <= 0)
-			return err;
-	}
-
-	hdr.seq = dr->snd_nxt;
-	delay = 1;
-	do {
-		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
-		if (err > 0) {
-			dr->snd_nxt++;
-			break;
-		}
-		udelay(delay);
-		if ((delay <<= 1) > 128)
-			delay = 128;
-		if (retries++ > VNET_MAX_RETRIES)
-			break;
-	} while (err == -EAGAIN);
-	trace_vnet_tx_trigger(port->vio._local_sid,
-			      port->vio._peer_sid, start, err);
-
-	return err;
-}
-
-struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
-{
-	unsigned int hash = vnet_hashfn(skb->data);
-	struct hlist_head *hp = &vp->port_hash[hash];
-	struct vnet_port *port;
-
-	hlist_for_each_entry_rcu(port, hp, hash) {
-		if (!port_is_up(port))
-			continue;
-		if (ether_addr_equal(port->raddr, skb->data))
-			return port;
-	}
-	list_for_each_entry_rcu(port, &vp->port_list, list) {
-		if (!port->switch_port)
-			continue;
-		if (!port_is_up(port))
-			continue;
-		return port;
-	}
-	return NULL;
-}
-
-static struct sk_buff *vnet_clean_tx_ring(struct vnet_port *port,
-					  unsigned *pending)
-{
-	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-	struct sk_buff *skb = NULL;
-	int i, txi;
-
-	*pending = 0;
-
-	txi = dr->prod;
-	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
-		struct vio_net_desc *d;
-
-		--txi;
-		if (txi < 0)
-			txi = VNET_TX_RING_SIZE-1;
-
-		d = vio_dring_entry(dr, txi);
-
-		if (d->hdr.state == VIO_DESC_READY) {
-			(*pending)++;
-			continue;
-		}
-		if (port->tx_bufs[txi].skb) {
-			if (d->hdr.state != VIO_DESC_DONE)
-				pr_notice("invalid ring buffer state %d\n",
-					  d->hdr.state);
-			BUG_ON(port->tx_bufs[txi].skb->next);
-
-			port->tx_bufs[txi].skb->next = skb;
-			skb = port->tx_bufs[txi].skb;
-			port->tx_bufs[txi].skb = NULL;
-
-			ldc_unmap(port->vio.lp,
-				  port->tx_bufs[txi].cookies,
-				  port->tx_bufs[txi].ncookies);
-		} else if (d->hdr.state == VIO_DESC_FREE)
-			break;
-		d->hdr.state = VIO_DESC_FREE;
-	}
-	return skb;
-}
-
-static inline void vnet_free_skbs(struct sk_buff *skb)
-{
-	struct sk_buff *next;
-
-	while (skb) {
-		next = skb->next;
-		skb->next = NULL;
-		dev_kfree_skb(skb);
-		skb = next;
-	}
-}
-
-static void vnet_clean_timer_expire(unsigned long port0)
-{
-	struct vnet_port *port = (struct vnet_port *)port0;
-	struct sk_buff *freeskbs;
-	unsigned pending;
-
-	netif_tx_lock(port->vp->dev);
-	freeskbs = vnet_clean_tx_ring(port, &pending);
-	netif_tx_unlock(port->vp->dev);
-
-	vnet_free_skbs(freeskbs);
-
-	if (pending)
-		(void)mod_timer(&port->clean_timer,
-				jiffies + VNET_CLEAN_TIMEOUT);
-	 else
-		del_timer(&port->clean_timer);
-}
-
-static inline int vnet_skb_map(struct ldc_channel *lp, struct sk_buff *skb,
-			       struct ldc_trans_cookie *cookies, int ncookies,
-			       unsigned int map_perm)
-{
-	int i, nc, err, blen;
-
-	/* header */
-	blen = skb_headlen(skb);
-	if (blen < ETH_ZLEN)
-		blen = ETH_ZLEN;
-	blen += VNET_PACKET_SKIP;
-	blen += 8 - (blen & 7);
-
-	err = ldc_map_single(lp, skb->data-VNET_PACKET_SKIP, blen, cookies,
-			     ncookies, map_perm);
-	if (err < 0)
-		return err;
-	nc = err;
-
-	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
-		u8 *vaddr;
-
-		if (nc < ncookies) {
-			vaddr = kmap_atomic(skb_frag_page(f));
-			blen = skb_frag_size(f);
-			blen += 8 - (blen & 7);
-			err = ldc_map_single(lp, vaddr + f->page_offset,
-					     blen, cookies + nc, ncookies - nc,
-					     map_perm);
-			kunmap_atomic(vaddr);
-		} else {
-			err = -EMSGSIZE;
-		}
-
-		if (err < 0) {
-			ldc_unmap(lp, cookies, nc);
-			return err;
-		}
-		nc += err;
-	}
-	return nc;
-}
-
-static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, int ncookies)
-{
-	struct sk_buff *nskb;
-	int i, len, pad, docopy;
-
-	len = skb->len;
-	pad = 0;
-	if (len < ETH_ZLEN) {
-		pad += ETH_ZLEN - skb->len;
-		len += pad;
-	}
-	len += VNET_PACKET_SKIP;
-	pad += 8 - (len & 7);
-
-	/* make sure we have enough cookies and alignment in every frag */
-	docopy = skb_shinfo(skb)->nr_frags >= ncookies;
-	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
-
-		docopy |= f->page_offset & 7;
-	}
-	if (((unsigned long)skb->data & 7) != VNET_PACKET_SKIP ||
-	    skb_tailroom(skb) < pad ||
-	    skb_headroom(skb) < VNET_PACKET_SKIP || docopy) {
-		int start = 0, offset;
-		__wsum csum;
-
-		len = skb->len > ETH_ZLEN ? skb->len : ETH_ZLEN;
-		nskb = alloc_and_align_skb(skb->dev, len);
-		if (nskb == NULL) {
-			dev_kfree_skb(skb);
-			return NULL;
-		}
-		skb_reserve(nskb, VNET_PACKET_SKIP);
-
-		nskb->protocol = skb->protocol;
-		offset = skb_mac_header(skb) - skb->data;
-		skb_set_mac_header(nskb, offset);
-		offset = skb_network_header(skb) - skb->data;
-		skb_set_network_header(nskb, offset);
-		offset = skb_transport_header(skb) - skb->data;
-		skb_set_transport_header(nskb, offset);
-
-		offset = 0;
-		nskb->csum_offset = skb->csum_offset;
-		nskb->ip_summed = skb->ip_summed;
-
-		if (skb->ip_summed == CHECKSUM_PARTIAL)
-			start = skb_checksum_start_offset(skb);
-		if (start) {
-			struct iphdr *iph = ip_hdr(nskb);
-			int offset = start + nskb->csum_offset;
-
-			if (skb_copy_bits(skb, 0, nskb->data, start)) {
-				dev_kfree_skb(nskb);
-				dev_kfree_skb(skb);
-				return NULL;
-			}
-			*(__sum16 *)(skb->data + offset) = 0;
-			csum = skb_copy_and_csum_bits(skb, start,
-						      nskb->data + start,
-						      skb->len - start, 0);
-			if (iph->protocol == IPPROTO_TCP ||
-			    iph->protocol == IPPROTO_UDP) {
-				csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
-							 skb->len - start,
-							 iph->protocol, csum);
-			}
-			*(__sum16 *)(nskb->data + offset) = csum;
-
-			nskb->ip_summed = CHECKSUM_NONE;
-		} else if (skb_copy_bits(skb, 0, nskb->data, skb->len)) {
-			dev_kfree_skb(nskb);
-			dev_kfree_skb(skb);
-			return NULL;
-		}
-		(void)skb_put(nskb, skb->len);
-		if (skb_is_gso(skb)) {
-			skb_shinfo(nskb)->gso_size = skb_shinfo(skb)->gso_size;
-			skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
-		}
-		nskb->queue_mapping = skb->queue_mapping;
-		dev_kfree_skb(skb);
-		skb = nskb;
-	}
-	return skb;
-}
-
-static u16
-vnet_select_queue(struct net_device *dev, struct sk_buff *skb,
-		  void *accel_priv, select_queue_fallback_t fallback)
-{
-	struct vnet *vp = netdev_priv(dev);
-	struct vnet_port *port = __tx_port_find(vp, skb);
-
-	if (port == NULL)
-		return 0;
-	return port->q_index;
-}
-
-static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev);
-
-static int vnet_handle_offloads(struct vnet_port *port, struct sk_buff *skb)
-{
-	struct net_device *dev = port->vp->dev;
-	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-	struct sk_buff *segs;
-	int maclen, datalen;
-	int status;
-	int gso_size, gso_type, gso_segs;
-	int hlen = skb_transport_header(skb) - skb_mac_header(skb);
-	int proto = IPPROTO_IP;
-
-	if (skb->protocol == htons(ETH_P_IP))
-		proto = ip_hdr(skb)->protocol;
-	else if (skb->protocol == htons(ETH_P_IPV6))
-		proto = ipv6_hdr(skb)->nexthdr;
-
-	if (proto == IPPROTO_TCP)
-		hlen += tcp_hdr(skb)->doff * 4;
-	else if (proto == IPPROTO_UDP)
-		hlen += sizeof(struct udphdr);
-	else {
-		pr_err("vnet_handle_offloads GSO with unknown transport "
-		       "protocol %d tproto %d\n", skb->protocol, proto);
-		hlen = 128; /* XXX */
-	}
-	datalen = port->tsolen - hlen;
-
-	gso_size = skb_shinfo(skb)->gso_size;
-	gso_type = skb_shinfo(skb)->gso_type;
-	gso_segs = skb_shinfo(skb)->gso_segs;
-
-	if (port->tso && gso_size < datalen)
-		gso_segs = DIV_ROUND_UP(skb->len - hlen, datalen);
-
-	if (unlikely(vnet_tx_dring_avail(dr) < gso_segs)) {
-		struct netdev_queue *txq;
-
-		txq  = netdev_get_tx_queue(dev, port->q_index);
-		netif_tx_stop_queue(txq);
-		if (vnet_tx_dring_avail(dr) < skb_shinfo(skb)->gso_segs)
-			return NETDEV_TX_BUSY;
-		netif_tx_wake_queue(txq);
-	}
-
-	maclen = skb_network_header(skb) - skb_mac_header(skb);
-	skb_pull(skb, maclen);
-
-	if (port->tso && gso_size < datalen) {
-		if (skb_unclone(skb, GFP_ATOMIC))
-			goto out_dropped;
-
-		/* segment to TSO size */
-		skb_shinfo(skb)->gso_size = datalen;
-		skb_shinfo(skb)->gso_segs = gso_segs;
-	}
-	segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO);
-	if (IS_ERR(segs))
-		goto out_dropped;
-
-	skb_push(skb, maclen);
-	skb_reset_mac_header(skb);
-
-	status = 0;
-	while (segs) {
-		struct sk_buff *curr = segs;
-
-		segs = segs->next;
-		curr->next = NULL;
-		if (port->tso && curr->len > dev->mtu) {
-			skb_shinfo(curr)->gso_size = gso_size;
-			skb_shinfo(curr)->gso_type = gso_type;
-			skb_shinfo(curr)->gso_segs =
-				DIV_ROUND_UP(curr->len - hlen, gso_size);
-		} else
-			skb_shinfo(curr)->gso_size = 0;
-
-		skb_push(curr, maclen);
-		skb_reset_mac_header(curr);
-		memcpy(skb_mac_header(curr), skb_mac_header(skb),
-		       maclen);
-		curr->csum_start = skb_transport_header(curr) - curr->head;
-		if (ip_hdr(curr)->protocol == IPPROTO_TCP)
-			curr->csum_offset = offsetof(struct tcphdr, check);
-		else if (ip_hdr(curr)->protocol == IPPROTO_UDP)
-			curr->csum_offset = offsetof(struct udphdr, check);
-
-		if (!(status & NETDEV_TX_MASK))
-			status = vnet_start_xmit(curr, dev);
-		if (status & NETDEV_TX_MASK)
-			dev_kfree_skb_any(curr);
-	}
-
-	if (!(status & NETDEV_TX_MASK))
-		dev_kfree_skb_any(skb);
-	return status;
-out_dropped:
-	dev->stats.tx_dropped++;
-	dev_kfree_skb_any(skb);
-	return NETDEV_TX_OK;
-}
-
-static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev)
-{
-	struct vnet *vp = netdev_priv(dev);
-	struct vnet_port *port = NULL;
-	struct vio_dring_state *dr;
-	struct vio_net_desc *d;
-	unsigned int len;
-	struct sk_buff *freeskbs = NULL;
-	int i, err, txi;
-	unsigned pending = 0;
-	struct netdev_queue *txq;
-
-	rcu_read_lock();
-	port = __tx_port_find(vp, skb);
-	if (unlikely(!port)) {
-		rcu_read_unlock();
-		goto out_dropped;
-	}
-
-	if (skb_is_gso(skb) && skb->len > port->tsolen) {
-		err = vnet_handle_offloads(port, skb);
-		rcu_read_unlock();
-		return err;
-	}
-
-	if (!skb_is_gso(skb) && skb->len > port->rmtu) {
-		unsigned long localmtu = port->rmtu - ETH_HLEN;
-
-		if (vio_version_after_eq(&port->vio, 1, 3))
-			localmtu -= VLAN_HLEN;
-
-		if (skb->protocol == htons(ETH_P_IP)) {
-			struct flowi4 fl4;
-			struct rtable *rt = NULL;
-
-			memset(&fl4, 0, sizeof(fl4));
-			fl4.flowi4_oif = dev->ifindex;
-			fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
-			fl4.daddr = ip_hdr(skb)->daddr;
-			fl4.saddr = ip_hdr(skb)->saddr;
-
-			rt = ip_route_output_key(dev_net(dev), &fl4);
-			rcu_read_unlock();
-			if (!IS_ERR(rt)) {
-				skb_dst_set(skb, &rt->dst);
-				icmp_send(skb, ICMP_DEST_UNREACH,
-					  ICMP_FRAG_NEEDED,
-					  htonl(localmtu));
-			}
-		}
-#if IS_ENABLED(CONFIG_IPV6)
-		else if (skb->protocol == htons(ETH_P_IPV6))
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, localmtu);
-#endif
-		goto out_dropped;
-	}
-
-	skb = vnet_skb_shape(skb, 2);
-
-	if (unlikely(!skb))
-		goto out_dropped;
-
-	if (skb->ip_summed == CHECKSUM_PARTIAL)
-		vnet_fullcsum(skb);
-
-	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-	i = skb_get_queue_mapping(skb);
-	txq = netdev_get_tx_queue(dev, i);
-	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
-		if (!netif_tx_queue_stopped(txq)) {
-			netif_tx_stop_queue(txq);
-
-			/* This is a hard error, log it. */
-			netdev_err(dev, "BUG! Tx Ring full when queue awake!\n");
-			dev->stats.tx_errors++;
-		}
-		rcu_read_unlock();
-		return NETDEV_TX_BUSY;
-	}
-
-	d = vio_dring_cur(dr);
-
-	txi = dr->prod;
-
-	freeskbs = vnet_clean_tx_ring(port, &pending);
-
-	BUG_ON(port->tx_bufs[txi].skb);
-
-	len = skb->len;
-	if (len < ETH_ZLEN)
-		len = ETH_ZLEN;
-
-	err = vnet_skb_map(port->vio.lp, skb, port->tx_bufs[txi].cookies, 2,
-			   (LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_RW));
-	if (err < 0) {
-		netdev_info(dev, "tx buffer map error %d\n", err);
-		goto out_dropped;
-	}
-
-	port->tx_bufs[txi].skb = skb;
-	skb = NULL;
-	port->tx_bufs[txi].ncookies = err;
-
-	/* We don't rely on the ACKs to free the skb in vnet_start_xmit(),
-	 * thus it is safe to not set VIO_ACK_ENABLE for each transmission:
-	 * the protocol itself does not require it as long as the peer
-	 * sends a VIO_SUBTYPE_ACK for VIO_DRING_STOPPED.
-	 *
-	 * An ACK for every packet in the ring is expensive as the
-	 * sending of LDC messages is slow and affects performance.
-	 */
-	d->hdr.ack = VIO_ACK_DISABLE;
-	d->size = len;
-	d->ncookies = port->tx_bufs[txi].ncookies;
-	for (i = 0; i < d->ncookies; i++)
-		d->cookies[i] = port->tx_bufs[txi].cookies[i];
-	if (vio_version_after_eq(&port->vio, 1, 7)) {
-		struct vio_net_dext *dext = vio_net_ext(d);
-
-		memset(dext, 0, sizeof(*dext));
-		if (skb_is_gso(port->tx_bufs[txi].skb)) {
-			dext->ipv4_lso_mss = skb_shinfo(port->tx_bufs[txi].skb)
-					     ->gso_size;
-			dext->flags |= VNET_PKT_IPV4_LSO;
-		}
-		if (vio_version_after_eq(&port->vio, 1, 8) &&
-		    !port->switch_port) {
-			dext->flags |= VNET_PKT_HCK_IPV4_HDRCKSUM_OK;
-			dext->flags |= VNET_PKT_HCK_FULLCKSUM_OK;
-		}
-	}
-
-	/* This has to be a non-SMP write barrier because we are writing
-	 * to memory which is shared with the peer LDOM.
-	 */
-	dma_wmb();
-
-	d->hdr.state = VIO_DESC_READY;
-
-	/* Exactly one ldc "start" trigger (for dr->cons) needs to be sent
-	 * to notify the consumer that some descriptors are READY.
-	 * After that "start" trigger, no additional triggers are needed until
-	 * a DRING_STOPPED is received from the consumer. The dr->cons field
-	 * (set up by vnet_ack()) has the value of the next dring index
-	 * that has not yet been ack-ed. We send a "start" trigger here
-	 * if, and only if, start_cons is true (reset it afterward). Conversely,
-	 * vnet_ack() should check if the dring corresponding to cons
-	 * is marked READY, but start_cons was false.
-	 * If so, vnet_ack() should send out the missed "start" trigger.
-	 *
-	 * Note that the dma_wmb() above makes sure the cookies et al. are
-	 * not globally visible before the VIO_DESC_READY, and that the
-	 * stores are ordered correctly by the compiler. The consumer will
-	 * not proceed until the VIO_DESC_READY is visible assuring that
-	 * the consumer does not observe anything related to descriptors
-	 * out of order. The HV trap from the LDC start trigger is the
-	 * producer to consumer announcement that work is available to the
-	 * consumer
-	 */
-	if (!port->start_cons) { /* previous trigger suffices */
-		trace_vnet_skip_tx_trigger(port->vio._local_sid,
-					   port->vio._peer_sid, dr->cons);
-		goto ldc_start_done;
-	}
-
-	err = __vnet_tx_trigger(port, dr->cons);
-	if (unlikely(err < 0)) {
-		netdev_info(dev, "TX trigger error %d\n", err);
-		d->hdr.state = VIO_DESC_FREE;
-		skb = port->tx_bufs[txi].skb;
-		port->tx_bufs[txi].skb = NULL;
-		dev->stats.tx_carrier_errors++;
-		goto out_dropped;
-	}
-
-ldc_start_done:
-	port->start_cons = false;
-
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += port->tx_bufs[txi].skb->len;
-
-	dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1);
-	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
-		netif_tx_stop_queue(txq);
-		if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr))
-			netif_tx_wake_queue(txq);
-	}
-
-	(void)mod_timer(&port->clean_timer, jiffies + VNET_CLEAN_TIMEOUT);
-	rcu_read_unlock();
-
-	vnet_free_skbs(freeskbs);
-
-	return NETDEV_TX_OK;
-
-out_dropped:
-	if (pending)
-		(void)mod_timer(&port->clean_timer,
-				jiffies + VNET_CLEAN_TIMEOUT);
-	else if (port)
-		del_timer(&port->clean_timer);
-	if (port)
-		rcu_read_unlock();
-	if (skb)
-		dev_kfree_skb(skb);
-	vnet_free_skbs(freeskbs);
-	dev->stats.tx_dropped++;
-	return NETDEV_TX_OK;
-}
-
-static void vnet_tx_timeout(struct net_device *dev)
-{
-	/* XXX Implement me XXX */
-}
-
-static int vnet_open(struct net_device *dev)
-{
-	netif_carrier_on(dev);
-	netif_tx_start_all_queues(dev);
-
-	return 0;
-}
-
-static int vnet_close(struct net_device *dev)
-{
-	netif_tx_stop_all_queues(dev);
-	netif_carrier_off(dev);
-
-	return 0;
-}
-
-static struct vnet_mcast_entry *__vnet_mc_find(struct vnet *vp, u8 *addr)
-{
-	struct vnet_mcast_entry *m;
-
-	for (m = vp->mcast_list; m; m = m->next) {
-		if (ether_addr_equal(m->addr, addr))
-			return m;
-	}
-	return NULL;
-}
-
-static void __update_mc_list(struct vnet *vp, struct net_device *dev)
-{
-	struct netdev_hw_addr *ha;
-
-	netdev_for_each_mc_addr(ha, dev) {
-		struct vnet_mcast_entry *m;
-
-		m = __vnet_mc_find(vp, ha->addr);
-		if (m) {
-			m->hit = 1;
-			continue;
-		}
-
-		if (!m) {
-			m = kzalloc(sizeof(*m), GFP_ATOMIC);
-			if (!m)
-				continue;
-			memcpy(m->addr, ha->addr, ETH_ALEN);
-			m->hit = 1;
-
-			m->next = vp->mcast_list;
-			vp->mcast_list = m;
-		}
-	}
-}
-
-static void __send_mc_list(struct vnet *vp, struct vnet_port *port)
-{
-	struct vio_net_mcast_info info;
-	struct vnet_mcast_entry *m, **pp;
-	int n_addrs;
-
-	memset(&info, 0, sizeof(info));
-
-	info.tag.type = VIO_TYPE_CTRL;
-	info.tag.stype = VIO_SUBTYPE_INFO;
-	info.tag.stype_env = VNET_MCAST_INFO;
-	info.tag.sid = vio_send_sid(&port->vio);
-	info.set = 1;
-
-	n_addrs = 0;
-	for (m = vp->mcast_list; m; m = m->next) {
-		if (m->sent)
-			continue;
-		m->sent = 1;
-		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
-		       m->addr, ETH_ALEN);
-		if (++n_addrs == VNET_NUM_MCAST) {
-			info.count = n_addrs;
-
-			(void) vio_ldc_send(&port->vio, &info,
-					    sizeof(info));
-			n_addrs = 0;
-		}
-	}
-	if (n_addrs) {
-		info.count = n_addrs;
-		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
-	}
-
-	info.set = 0;
-
-	n_addrs = 0;
-	pp = &vp->mcast_list;
-	while ((m = *pp) != NULL) {
-		if (m->hit) {
-			m->hit = 0;
-			pp = &m->next;
-			continue;
-		}
-
-		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
-		       m->addr, ETH_ALEN);
-		if (++n_addrs == VNET_NUM_MCAST) {
-			info.count = n_addrs;
-			(void) vio_ldc_send(&port->vio, &info,
-					    sizeof(info));
-			n_addrs = 0;
-		}
-
-		*pp = m->next;
-		kfree(m);
-	}
-	if (n_addrs) {
-		info.count = n_addrs;
-		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
-	}
-}
-
-static void vnet_set_rx_mode(struct net_device *dev)
-{
-	struct vnet *vp = netdev_priv(dev);
-	struct vnet_port *port;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(port, &vp->port_list, list) {
-
-		if (port->switch_port) {
-			__update_mc_list(vp, dev);
-			__send_mc_list(vp, port);
-			break;
-		}
-	}
-	rcu_read_unlock();
-}
-
-static int vnet_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if (new_mtu < 68 || new_mtu > 65535)
-		return -EINVAL;
-
-	dev->mtu = new_mtu;
-	return 0;
-}
-
-static int vnet_set_mac_addr(struct net_device *dev, void *p)
-{
-	return -EINVAL;
-}
-
 static void vnet_get_drvinfo(struct net_device *dev,
 			     struct ethtool_drvinfo *info)
 {
@@ -1660,129 +81,21 @@ static const struct ethtool_ops vnet_ethtool_ops = {
 	.get_link		= ethtool_op_get_link,
 };
 
-static void vnet_port_free_tx_bufs(struct vnet_port *port)
-{
-	struct vio_dring_state *dr;
-	int i;
-
-	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-
-	if (dr->base == NULL)
-		return;
-
-	for (i = 0; i < VNET_TX_RING_SIZE; i++) {
-		struct vio_net_desc *d;
-		void *skb = port->tx_bufs[i].skb;
-
-		if (!skb)
-			continue;
-
-		d = vio_dring_entry(dr, i);
-
-		ldc_unmap(port->vio.lp,
-			  port->tx_bufs[i].cookies,
-			  port->tx_bufs[i].ncookies);
-		dev_kfree_skb(skb);
-		port->tx_bufs[i].skb = NULL;
-		d->hdr.state = VIO_DESC_FREE;
-	}
-	ldc_free_exp_dring(port->vio.lp, dr->base,
-			   (dr->entry_size * dr->num_entries),
-			   dr->cookies, dr->ncookies);
-	dr->base = NULL;
-	dr->entry_size = 0;
-	dr->num_entries = 0;
-	dr->pending = 0;
-	dr->ncookies = 0;
-}
-
-static void vnet_port_reset(struct vnet_port *port)
-{
-	del_timer(&port->clean_timer);
-	vnet_port_free_tx_bufs(port);
-	port->rmtu = 0;
-	port->tso = true;
-	port->tsolen = 0;
-}
-
-static int vnet_port_alloc_tx_ring(struct vnet_port *port)
-{
-	struct vio_dring_state *dr;
-	unsigned long len, elen;
-	int i, err, ncookies;
-	void *dring;
-
-	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-
-	elen = sizeof(struct vio_net_desc) +
-	       sizeof(struct ldc_trans_cookie) * 2;
-	if (vio_version_after_eq(&port->vio, 1, 7))
-		elen += sizeof(struct vio_net_dext);
-	len = VNET_TX_RING_SIZE * elen;
-
-	ncookies = VIO_MAX_RING_COOKIES;
-	dring = ldc_alloc_exp_dring(port->vio.lp, len,
-				    dr->cookies, &ncookies,
-				    (LDC_MAP_SHADOW |
-				     LDC_MAP_DIRECT |
-				     LDC_MAP_RW));
-	if (IS_ERR(dring)) {
-		err = PTR_ERR(dring);
-		goto err_out;
-	}
-
-	dr->base = dring;
-	dr->entry_size = elen;
-	dr->num_entries = VNET_TX_RING_SIZE;
-	dr->prod = dr->cons = 0;
-	port->start_cons  = true; /* need an initial trigger */
-	dr->pending = VNET_TX_RING_SIZE;
-	dr->ncookies = ncookies;
-
-	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
-		struct vio_net_desc *d;
-
-		d = vio_dring_entry(dr, i);
-		d->hdr.state = VIO_DESC_FREE;
-	}
-	return 0;
-
-err_out:
-	vnet_port_free_tx_bufs(port);
-
-	return err;
-}
-
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void vnet_poll_controller(struct net_device *dev)
-{
-	struct vnet *vp = netdev_priv(dev);
-	struct vnet_port *port;
-	unsigned long flags;
-
-	spin_lock_irqsave(&vp->lock, flags);
-	if (!list_empty(&vp->port_list)) {
-		port = list_entry(vp->port_list.next, struct vnet_port, list);
-		napi_schedule(&port->napi);
-	}
-	spin_unlock_irqrestore(&vp->lock, flags);
-}
-#endif
 static LIST_HEAD(vnet_list);
 static DEFINE_MUTEX(vnet_list_mutex);
 
 static const struct net_device_ops vnet_ops = {
-	.ndo_open		= vnet_open,
-	.ndo_stop		= vnet_close,
-	.ndo_set_rx_mode	= vnet_set_rx_mode,
-	.ndo_set_mac_address	= vnet_set_mac_addr,
+	.ndo_open		= sunvnet_open_common,
+	.ndo_stop		= sunvnet_close_common,
+	.ndo_set_rx_mode	= sunvnet_set_rx_mode_common,
+	.ndo_set_mac_address	= sunvnet_set_mac_addr_common,
 	.ndo_validate_addr	= eth_validate_addr,
-	.ndo_tx_timeout		= vnet_tx_timeout,
-	.ndo_change_mtu		= vnet_change_mtu,
-	.ndo_start_xmit		= vnet_start_xmit,
-	.ndo_select_queue	= vnet_select_queue,
+	.ndo_tx_timeout		= sunvnet_tx_timeout_common,
+	.ndo_change_mtu		= sunvnet_change_mtu_common,
+	.ndo_start_xmit		= sunvnet_start_xmit_common,
+	.ndo_select_queue	= sunvnet_select_queue_common,
 #ifdef CONFIG_NET_POLL_CONTROLLER
-	.ndo_poll_controller	= vnet_poll_controller,
+	.ndo_poll_controller	= sunvnet_poll_controller_common,
 #endif
 };
 
@@ -1908,15 +221,15 @@ static struct vnet *vnet_find_parent(struct mdesc_handle *hp,
 }
 
 static struct ldc_channel_config vnet_ldc_cfg = {
-	.event		= vnet_event,
+	.event		= sunvnet_event_common,
 	.mtu		= 64,
 	.mode		= LDC_MODE_UNRELIABLE,
 };
 
 static struct vio_driver_ops vnet_vio_ops = {
-	.send_attr		= vnet_send_attr,
-	.handle_attr		= vnet_handle_attr,
-	.handshake_complete	= vnet_handshake_complete,
+	.send_attr		= sunvnet_send_attr_common,
+	.handle_attr		= sunvnet_handle_attr_common,
+	.handshake_complete	= sunvnet_handshake_complete_common,
 };
 
 static void print_version(void)
@@ -1926,25 +239,6 @@ static void print_version(void)
 
 const char *remote_macaddr_prop = "remote-mac-address";
 
-static void
-vnet_port_add_txq(struct vnet_port *port)
-{
-	struct vnet *vp = port->vp;
-	int n;
-
-	n = vp->nports++;
-	n = n & (VNET_MAX_TXQS - 1);
-	port->q_index = n;
-	netif_tx_wake_queue(netdev_get_tx_queue(vp->dev, port->q_index));
-}
-
-static void
-vnet_port_rm_txq(struct vnet_port *port)
-{
-	port->vp->nports--;
-	netif_tx_stop_queue(netdev_get_tx_queue(port->vp->dev, port->q_index));
-}
-
 static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 {
 	struct mdesc_handle *hp;
@@ -1992,7 +286,8 @@ static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	if (err)
 		goto err_out_free_port;
 
-	netif_napi_add(port->vp->dev, &port->napi, vnet_poll, NAPI_POLL_WEIGHT);
+	netif_napi_add(port->vp->dev, &port->napi, sunvnet_poll_common,
+		       NAPI_POLL_WEIGHT);
 
 	INIT_HLIST_NODE(&port->hash);
 	INIT_LIST_HEAD(&port->list);
@@ -2011,7 +306,7 @@ static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 		list_add_tail_rcu(&port->list, &vp->port_list);
 	hlist_add_head_rcu(&port->hash,
 			   &vp->port_hash[vnet_hashfn(port->raddr)]);
-	vnet_port_add_txq(port);
+	sunvnet_port_add_txq_common(port);
 	spin_unlock_irqrestore(&vp->lock, flags);
 
 	dev_set_drvdata(&vdev->dev, port);
@@ -2019,7 +314,7 @@ static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	pr_info("%s: PORT ( remote-mac %pM%s )\n",
 		vp->dev->name, port->raddr, switch_port ? " switch-port" : "");
 
-	setup_timer(&port->clean_timer, vnet_clean_timer_expire,
+	setup_timer(&port->clean_timer, sunvnet_clean_timer_expire_common,
 		    (unsigned long)port);
 
 	napi_enable(&port->napi);
@@ -2052,9 +347,9 @@ static int vnet_port_remove(struct vio_dev *vdev)
 
 		synchronize_rcu();
 		del_timer_sync(&port->clean_timer);
-		vnet_port_rm_txq(port);
+		sunvnet_port_rm_txq_common(port);
 		netif_napi_del(&port->napi);
-		vnet_port_free_tx_bufs(port);
+		sunvnet_port_free_tx_bufs_common(port);
 		vio_ldc_free(&port->vio);
 
 		dev_set_drvdata(&vdev->dev, NULL);
diff --git a/drivers/net/ethernet/sun/sunvnet_common.c b/drivers/net/ethernet/sun/sunvnet_common.c
new file mode 100644
index 000000000000..49e85d0d960b
--- /dev/null
+++ b/drivers/net/ethernet/sun/sunvnet_common.c
@@ -0,0 +1,1753 @@
+/* sunvnet.c: Sun LDOM Virtual Network Driver.
+ *
+ * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/ethtool.h>
+#include <linux/etherdevice.h>
+#include <linux/mutex.h>
+#include <linux/highmem.h>
+#include <linux/if_vlan.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/sunvnet.h>
+
+#if IS_ENABLED(CONFIG_IPV6)
+#include <linux/icmpv6.h>
+#endif
+
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/route.h>
+
+#include <asm/vio.h>
+#include <asm/ldc.h>
+
+#include "sunvnet_common.h"
+
+/* Heuristic for the number of times to exponentially backoff and
+ * retry sending an LDC trigger when EAGAIN is encountered
+ */
+#define	VNET_MAX_RETRIES	10
+
+static int __vnet_tx_trigger(struct vnet_port *port, u32 start);
+static void vnet_port_reset(struct vnet_port *port);
+
+static inline u32 vnet_tx_dring_avail(struct vio_dring_state *dr)
+{
+	return vio_dring_avail(dr, VNET_TX_RING_SIZE);
+}
+
+static int vnet_handle_unknown(struct vnet_port *port, void *arg)
+{
+	struct vio_msg_tag *pkt = arg;
+
+	pr_err("Received unknown msg [%02x:%02x:%04x:%08x]\n",
+	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
+	pr_err("Resetting connection\n");
+
+	ldc_disconnect(port->vio.lp);
+
+	return -ECONNRESET;
+}
+
+static int vnet_port_alloc_tx_ring(struct vnet_port *port);
+
+int sunvnet_send_attr_common(struct vio_driver_state *vio)
+{
+	struct vnet_port *port = to_vnet_port(vio);
+	struct net_device *dev = port->vp->dev;
+	struct vio_net_attr_info pkt;
+	int framelen = ETH_FRAME_LEN;
+	int i, err;
+
+	err = vnet_port_alloc_tx_ring(to_vnet_port(vio));
+	if (err)
+		return err;
+
+	memset(&pkt, 0, sizeof(pkt));
+	pkt.tag.type = VIO_TYPE_CTRL;
+	pkt.tag.stype = VIO_SUBTYPE_INFO;
+	pkt.tag.stype_env = VIO_ATTR_INFO;
+	pkt.tag.sid = vio_send_sid(vio);
+	if (vio_version_before(vio, 1, 2))
+		pkt.xfer_mode = VIO_DRING_MODE;
+	else
+		pkt.xfer_mode = VIO_NEW_DRING_MODE;
+	pkt.addr_type = VNET_ADDR_ETHERMAC;
+	pkt.ack_freq = 0;
+	for (i = 0; i < 6; i++)
+		pkt.addr |= (u64)dev->dev_addr[i] << ((5 - i) * 8);
+	if (vio_version_after(vio, 1, 3)) {
+		if (port->rmtu) {
+			port->rmtu = min(VNET_MAXPACKET, port->rmtu);
+			pkt.mtu = port->rmtu;
+		} else {
+			port->rmtu = VNET_MAXPACKET;
+			pkt.mtu = port->rmtu;
+		}
+		if (vio_version_after_eq(vio, 1, 6))
+			pkt.options = VIO_TX_DRING;
+	} else if (vio_version_before(vio, 1, 3)) {
+		pkt.mtu = framelen;
+	} else { /* v1.3 */
+		pkt.mtu = framelen + VLAN_HLEN;
+	}
+
+	pkt.cflags = 0;
+	if (vio_version_after_eq(vio, 1, 7) && port->tso) {
+		pkt.cflags |= VNET_LSO_IPV4_CAPAB;
+		if (!port->tsolen)
+			port->tsolen = VNET_MAXTSO;
+		pkt.ipv4_lso_maxlen = port->tsolen;
+	}
+
+	pkt.plnk_updt = PHYSLINK_UPDATE_NONE;
+
+	viodbg(HS, "SEND NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
+	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
+	       "cflags[0x%04x] lso_max[%u]\n",
+	       pkt.xfer_mode, pkt.addr_type,
+	       (unsigned long long)pkt.addr,
+	       pkt.ack_freq, pkt.plnk_updt, pkt.options,
+	       (unsigned long long)pkt.mtu, pkt.cflags, pkt.ipv4_lso_maxlen);
+
+
+	return vio_ldc_send(vio, &pkt, sizeof(pkt));
+}
+EXPORT_SYMBOL_GPL(sunvnet_send_attr_common);
+
+static int handle_attr_info(struct vio_driver_state *vio,
+			    struct vio_net_attr_info *pkt)
+{
+	struct vnet_port *port = to_vnet_port(vio);
+	u64	localmtu;
+	u8	xfer_mode;
+
+	viodbg(HS, "GOT NET ATTR xmode[0x%x] atype[0x%x] addr[%llx] "
+	       "ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] mtu[%llu] "
+	       " (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
+	       pkt->xfer_mode, pkt->addr_type,
+	       (unsigned long long)pkt->addr,
+	       pkt->ack_freq, pkt->plnk_updt, pkt->options,
+	       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
+	       pkt->ipv4_lso_maxlen);
+
+	pkt->tag.sid = vio_send_sid(vio);
+
+	xfer_mode = pkt->xfer_mode;
+	/* for version < 1.2, VIO_DRING_MODE = 0x3 and no bitmask */
+	if (vio_version_before(vio, 1, 2) && xfer_mode == VIO_DRING_MODE)
+		xfer_mode = VIO_NEW_DRING_MODE;
+
+	/* MTU negotiation:
+	 *	< v1.3 - ETH_FRAME_LEN exactly
+	 *	> v1.3 - MIN(pkt.mtu, VNET_MAXPACKET, port->rmtu) and change
+	 *			pkt->mtu for ACK
+	 *	= v1.3 - ETH_FRAME_LEN + VLAN_HLEN exactly
+	 */
+	if (vio_version_before(vio, 1, 3)) {
+		localmtu = ETH_FRAME_LEN;
+	} else if (vio_version_after(vio, 1, 3)) {
+		localmtu = port->rmtu ? port->rmtu : VNET_MAXPACKET;
+		localmtu = min(pkt->mtu, localmtu);
+		pkt->mtu = localmtu;
+	} else { /* v1.3 */
+		localmtu = ETH_FRAME_LEN + VLAN_HLEN;
+	}
+	port->rmtu = localmtu;
+
+	/* LSO negotiation */
+	if (vio_version_after_eq(vio, 1, 7))
+		port->tso &= !!(pkt->cflags & VNET_LSO_IPV4_CAPAB);
+	else
+		port->tso = false;
+	if (port->tso) {
+		if (!port->tsolen)
+			port->tsolen = VNET_MAXTSO;
+		port->tsolen = min(port->tsolen, pkt->ipv4_lso_maxlen);
+		if (port->tsolen < VNET_MINTSO) {
+			port->tso = false;
+			port->tsolen = 0;
+			pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
+		}
+		pkt->ipv4_lso_maxlen = port->tsolen;
+	} else {
+		pkt->cflags &= ~VNET_LSO_IPV4_CAPAB;
+		pkt->ipv4_lso_maxlen = 0;
+	}
+
+	/* for version >= 1.6, ACK packet mode we support */
+	if (vio_version_after_eq(vio, 1, 6)) {
+		pkt->xfer_mode = VIO_NEW_DRING_MODE;
+		pkt->options = VIO_TX_DRING;
+	}
+
+	if (!(xfer_mode | VIO_NEW_DRING_MODE) ||
+	    pkt->addr_type != VNET_ADDR_ETHERMAC ||
+	    pkt->mtu != localmtu) {
+		viodbg(HS, "SEND NET ATTR NACK\n");
+
+		pkt->tag.stype = VIO_SUBTYPE_NACK;
+
+		(void) vio_ldc_send(vio, pkt, sizeof(*pkt));
+
+		return -ECONNRESET;
+	} else {
+		viodbg(HS, "SEND NET ATTR ACK xmode[0x%x] atype[0x%x] "
+		       "addr[%llx] ackfreq[%u] plnk_updt[0x%02x] opts[0x%02x] "
+		       "mtu[%llu] (rmtu[%llu]) cflags[0x%04x] lso_max[%u]\n",
+		       pkt->xfer_mode, pkt->addr_type,
+		       (unsigned long long)pkt->addr,
+		       pkt->ack_freq, pkt->plnk_updt, pkt->options,
+		       (unsigned long long)pkt->mtu, port->rmtu, pkt->cflags,
+		       pkt->ipv4_lso_maxlen);
+
+		pkt->tag.stype = VIO_SUBTYPE_ACK;
+
+		return vio_ldc_send(vio, pkt, sizeof(*pkt));
+	}
+
+}
+
+static int handle_attr_ack(struct vio_driver_state *vio,
+			   struct vio_net_attr_info *pkt)
+{
+	viodbg(HS, "GOT NET ATTR ACK\n");
+
+	return 0;
+}
+
+static int handle_attr_nack(struct vio_driver_state *vio,
+			    struct vio_net_attr_info *pkt)
+{
+	viodbg(HS, "GOT NET ATTR NACK\n");
+
+	return -ECONNRESET;
+}
+
+int sunvnet_handle_attr_common(struct vio_driver_state *vio, void *arg)
+{
+	struct vio_net_attr_info *pkt = arg;
+
+	switch (pkt->tag.stype) {
+	case VIO_SUBTYPE_INFO:
+		return handle_attr_info(vio, pkt);
+
+	case VIO_SUBTYPE_ACK:
+		return handle_attr_ack(vio, pkt);
+
+	case VIO_SUBTYPE_NACK:
+		return handle_attr_nack(vio, pkt);
+
+	default:
+		return -ECONNRESET;
+	}
+}
+EXPORT_SYMBOL_GPL(sunvnet_handle_attr_common);
+
+void sunvnet_handshake_complete_common(struct vio_driver_state *vio)
+{
+	struct vio_dring_state *dr;
+
+	dr = &vio->drings[VIO_DRIVER_RX_RING];
+	dr->snd_nxt = dr->rcv_nxt = 1;
+
+	dr = &vio->drings[VIO_DRIVER_TX_RING];
+	dr->snd_nxt = dr->rcv_nxt = 1;
+}
+EXPORT_SYMBOL_GPL(sunvnet_handshake_complete_common);
+
+/* The hypervisor interface that implements copying to/from imported
+ * memory from another domain requires that copies are done to 8-byte
+ * aligned buffers, and that the lengths of such copies are also 8-byte
+ * multiples.
+ *
+ * So we align skb->data to an 8-byte multiple and pad-out the data
+ * area so we can round the copy length up to the next multiple of
+ * 8 for the copy.
+ *
+ * The transmitter puts the actual start of the packet 6 bytes into
+ * the buffer it sends over, so that the IP headers after the ethernet
+ * header are aligned properly.  These 6 bytes are not in the descriptor
+ * length, they are simply implied.  This offset is represented using
+ * the VNET_PACKET_SKIP macro.
+ */
+static struct sk_buff *alloc_and_align_skb(struct net_device *dev,
+					   unsigned int len)
+{
+	struct sk_buff *skb = netdev_alloc_skb(dev, len+VNET_PACKET_SKIP+8+8);
+	unsigned long addr, off;
+
+	if (unlikely(!skb))
+		return NULL;
+
+	addr = (unsigned long) skb->data;
+	off = ((addr + 7UL) & ~7UL) - addr;
+	if (off)
+		skb_reserve(skb, off);
+
+	return skb;
+}
+
+static inline void vnet_fullcsum(struct sk_buff *skb)
+{
+	struct iphdr *iph = ip_hdr(skb);
+	int offset = skb_transport_offset(skb);
+
+	if (skb->protocol != htons(ETH_P_IP))
+		return;
+	if (iph->protocol != IPPROTO_TCP &&
+	    iph->protocol != IPPROTO_UDP)
+		return;
+	skb->ip_summed = CHECKSUM_NONE;
+	skb->csum_level = 1;
+	skb->csum = 0;
+	if (iph->protocol == IPPROTO_TCP) {
+		struct tcphdr *ptcp = tcp_hdr(skb);
+
+		ptcp->check = 0;
+		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
+		ptcp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
+						skb->len - offset, IPPROTO_TCP,
+						skb->csum);
+	} else if (iph->protocol == IPPROTO_UDP) {
+		struct udphdr *pudp = udp_hdr(skb);
+
+		pudp->check = 0;
+		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
+		pudp->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
+						skb->len - offset, IPPROTO_UDP,
+						skb->csum);
+	}
+}
+
+static int vnet_rx_one(struct vnet_port *port, struct vio_net_desc *desc)
+{
+	struct net_device *dev = port->vp->dev;
+	unsigned int len = desc->size;
+	unsigned int copy_len;
+	struct sk_buff *skb;
+	int maxlen;
+	int err;
+
+	err = -EMSGSIZE;
+	if (port->tso && port->tsolen > port->rmtu)
+		maxlen = port->tsolen;
+	else
+		maxlen = port->rmtu;
+	if (unlikely(len < ETH_ZLEN || len > maxlen)) {
+		dev->stats.rx_length_errors++;
+		goto out_dropped;
+	}
+
+	skb = alloc_and_align_skb(dev, len);
+	err = -ENOMEM;
+	if (unlikely(!skb)) {
+		dev->stats.rx_missed_errors++;
+		goto out_dropped;
+	}
+
+	copy_len = (len + VNET_PACKET_SKIP + 7U) & ~7U;
+	skb_put(skb, copy_len);
+	err = ldc_copy(port->vio.lp, LDC_COPY_IN,
+		       skb->data, copy_len, 0,
+		       desc->cookies, desc->ncookies);
+	if (unlikely(err < 0)) {
+		dev->stats.rx_frame_errors++;
+		goto out_free_skb;
+	}
+
+	skb_pull(skb, VNET_PACKET_SKIP);
+	skb_trim(skb, len);
+	skb->protocol = eth_type_trans(skb, dev);
+
+	if (vio_version_after_eq(&port->vio, 1, 8)) {
+		struct vio_net_dext *dext = vio_net_ext(desc);
+
+		skb_reset_network_header(skb);
+
+		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM) {
+			if (skb->protocol == ETH_P_IP) {
+				struct iphdr *iph = ip_hdr(skb);
+
+				iph->check = 0;
+				ip_send_check(iph);
+			}
+		}
+		if ((dext->flags & VNET_PKT_HCK_FULLCKSUM) &&
+		    skb->ip_summed == CHECKSUM_NONE) {
+			if (skb->protocol == htons(ETH_P_IP)) {
+				struct iphdr *iph = ip_hdr(skb);
+				int ihl = iph->ihl * 4;
+
+				skb_reset_transport_header(skb);
+				skb_set_transport_header(skb, ihl);
+				vnet_fullcsum(skb);
+			}
+		}
+		if (dext->flags & VNET_PKT_HCK_IPV4_HDRCKSUM_OK) {
+			skb->ip_summed = CHECKSUM_PARTIAL;
+			skb->csum_level = 0;
+			if (dext->flags & VNET_PKT_HCK_FULLCKSUM_OK)
+				skb->csum_level = 1;
+		}
+	}
+
+	skb->ip_summed = port->switch_port ? CHECKSUM_NONE : CHECKSUM_PARTIAL;
+
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += len;
+	napi_gro_receive(&port->napi, skb);
+	return 0;
+
+out_free_skb:
+	kfree_skb(skb);
+
+out_dropped:
+	dev->stats.rx_dropped++;
+	return err;
+}
+
+static int vnet_send_ack(struct vnet_port *port, struct vio_dring_state *dr,
+			 u32 start, u32 end, u8 vio_dring_state)
+{
+	struct vio_dring_data hdr = {
+		.tag = {
+			.type		= VIO_TYPE_DATA,
+			.stype		= VIO_SUBTYPE_ACK,
+			.stype_env	= VIO_DRING_DATA,
+			.sid		= vio_send_sid(&port->vio),
+		},
+		.dring_ident		= dr->ident,
+		.start_idx		= start,
+		.end_idx		= end,
+		.state			= vio_dring_state,
+	};
+	int err, delay;
+	int retries = 0;
+
+	hdr.seq = dr->snd_nxt;
+	delay = 1;
+	do {
+		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
+		if (err > 0) {
+			dr->snd_nxt++;
+			break;
+		}
+		udelay(delay);
+		if ((delay <<= 1) > 128)
+			delay = 128;
+		if (retries++ > VNET_MAX_RETRIES) {
+			pr_info("ECONNRESET %x:%x:%x:%x:%x:%x\n",
+				port->raddr[0], port->raddr[1],
+				port->raddr[2], port->raddr[3],
+				port->raddr[4], port->raddr[5]);
+			break;
+		}
+	} while (err == -EAGAIN);
+
+	if (err <= 0 && vio_dring_state == VIO_DRING_STOPPED) {
+		port->stop_rx_idx = end;
+		port->stop_rx = true;
+	} else {
+		port->stop_rx_idx = 0;
+		port->stop_rx = false;
+	}
+
+	return err;
+}
+
+static struct vio_net_desc *get_rx_desc(struct vnet_port *port,
+					struct vio_dring_state *dr,
+					u32 index)
+{
+	struct vio_net_desc *desc = port->vio.desc_buf;
+	int err;
+
+	err = ldc_get_dring_entry(port->vio.lp, desc, dr->entry_size,
+				  (index * dr->entry_size),
+				  dr->cookies, dr->ncookies);
+	if (err < 0)
+		return ERR_PTR(err);
+
+	return desc;
+}
+
+static int put_rx_desc(struct vnet_port *port,
+		       struct vio_dring_state *dr,
+		       struct vio_net_desc *desc,
+		       u32 index)
+{
+	int err;
+
+	err = ldc_put_dring_entry(port->vio.lp, desc, dr->entry_size,
+				  (index * dr->entry_size),
+				  dr->cookies, dr->ncookies);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int vnet_walk_rx_one(struct vnet_port *port,
+			    struct vio_dring_state *dr,
+			    u32 index, int *needs_ack)
+{
+	struct vio_net_desc *desc = get_rx_desc(port, dr, index);
+	struct vio_driver_state *vio = &port->vio;
+	int err;
+
+	BUG_ON(desc == NULL);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	if (desc->hdr.state != VIO_DESC_READY)
+		return 1;
+
+	dma_rmb();
+
+	viodbg(DATA, "vio_walk_rx_one desc[%02x:%02x:%08x:%08x:%llx:%llx]\n",
+	       desc->hdr.state, desc->hdr.ack,
+	       desc->size, desc->ncookies,
+	       desc->cookies[0].cookie_addr,
+	       desc->cookies[0].cookie_size);
+
+	err = vnet_rx_one(port, desc);
+	if (err == -ECONNRESET)
+		return err;
+	trace_vnet_rx_one(port->vio._local_sid, port->vio._peer_sid,
+			  index, desc->hdr.ack);
+	desc->hdr.state = VIO_DESC_DONE;
+	err = put_rx_desc(port, dr, desc, index);
+	if (err < 0)
+		return err;
+	*needs_ack = desc->hdr.ack;
+	return 0;
+}
+
+static int vnet_walk_rx(struct vnet_port *port, struct vio_dring_state *dr,
+			u32 start, u32 end, int *npkts, int budget)
+{
+	struct vio_driver_state *vio = &port->vio;
+	int ack_start = -1, ack_end = -1;
+	bool send_ack = true;
+
+	end = (end == (u32) -1) ? vio_dring_prev(dr, start)
+				: vio_dring_next(dr, end);
+
+	viodbg(DATA, "vnet_walk_rx start[%08x] end[%08x]\n", start, end);
+
+	while (start != end) {
+		int ack = 0, err = vnet_walk_rx_one(port, dr, start, &ack);
+		if (err == -ECONNRESET)
+			return err;
+		if (err != 0)
+			break;
+		(*npkts)++;
+		if (ack_start == -1)
+			ack_start = start;
+		ack_end = start;
+		start = vio_dring_next(dr, start);
+		if (ack && start != end) {
+			err = vnet_send_ack(port, dr, ack_start, ack_end,
+					    VIO_DRING_ACTIVE);
+			if (err == -ECONNRESET)
+				return err;
+			ack_start = -1;
+		}
+		if ((*npkts) >= budget) {
+			send_ack = false;
+			break;
+		}
+	}
+	if (unlikely(ack_start == -1))
+		ack_start = ack_end = vio_dring_prev(dr, start);
+	if (send_ack) {
+		port->napi_resume = false;
+		trace_vnet_tx_send_stopped_ack(port->vio._local_sid,
+					       port->vio._peer_sid,
+					       ack_end, *npkts);
+		return vnet_send_ack(port, dr, ack_start, ack_end,
+				     VIO_DRING_STOPPED);
+	} else  {
+		trace_vnet_tx_defer_stopped_ack(port->vio._local_sid,
+						port->vio._peer_sid,
+						ack_end, *npkts);
+		port->napi_resume = true;
+		port->napi_stop_idx = ack_end;
+		return 1;
+	}
+}
+
+static int vnet_rx(struct vnet_port *port, void *msgbuf, int *npkts,
+		   int budget)
+{
+	struct vio_dring_data *pkt = msgbuf;
+	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_RX_RING];
+	struct vio_driver_state *vio = &port->vio;
+
+	viodbg(DATA, "vnet_rx stype_env[%04x] seq[%016llx] rcv_nxt[%016llx]\n",
+	       pkt->tag.stype_env, pkt->seq, dr->rcv_nxt);
+
+	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
+		return 0;
+	if (unlikely(pkt->seq != dr->rcv_nxt)) {
+		pr_err("RX out of sequence seq[0x%llx] rcv_nxt[0x%llx]\n",
+		       pkt->seq, dr->rcv_nxt);
+		return 0;
+	}
+
+	if (!port->napi_resume)
+		dr->rcv_nxt++;
+
+	/* XXX Validate pkt->start_idx and pkt->end_idx XXX */
+
+	return vnet_walk_rx(port, dr, pkt->start_idx, pkt->end_idx,
+			    npkts, budget);
+}
+
+static int idx_is_pending(struct vio_dring_state *dr, u32 end)
+{
+	u32 idx = dr->cons;
+	int found = 0;
+
+	while (idx != dr->prod) {
+		if (idx == end) {
+			found = 1;
+			break;
+		}
+		idx = vio_dring_next(dr, idx);
+	}
+	return found;
+}
+
+static int vnet_ack(struct vnet_port *port, void *msgbuf)
+{
+	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+	struct vio_dring_data *pkt = msgbuf;
+	struct net_device *dev;
+	struct vnet *vp;
+	u32 end;
+	struct vio_net_desc *desc;
+	struct netdev_queue *txq;
+
+	if (unlikely(pkt->tag.stype_env != VIO_DRING_DATA))
+		return 0;
+
+	end = pkt->end_idx;
+	vp = port->vp;
+	dev = vp->dev;
+	netif_tx_lock(dev);
+	if (unlikely(!idx_is_pending(dr, end))) {
+		netif_tx_unlock(dev);
+		return 0;
+	}
+
+	/* sync for race conditions with vnet_start_xmit() and tell xmit it
+	 * is time to send a trigger.
+	 */
+	trace_vnet_rx_stopped_ack(port->vio._local_sid,
+				  port->vio._peer_sid, end);
+	dr->cons = vio_dring_next(dr, end);
+	desc = vio_dring_entry(dr, dr->cons);
+	if (desc->hdr.state == VIO_DESC_READY && !port->start_cons) {
+		/* vnet_start_xmit() just populated this dring but missed
+		 * sending the "start" LDC message to the consumer.
+		 * Send a "start" trigger on its behalf.
+		 */
+		if (__vnet_tx_trigger(port, dr->cons) > 0)
+			port->start_cons = false;
+		else
+			port->start_cons = true;
+	} else {
+		port->start_cons = true;
+	}
+	netif_tx_unlock(dev);
+
+	txq = netdev_get_tx_queue(dev, port->q_index);
+	if (unlikely(netif_tx_queue_stopped(txq) &&
+		     vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr)))
+		return 1;
+
+	return 0;
+}
+
+static int vnet_nack(struct vnet_port *port, void *msgbuf)
+{
+	/* XXX just reset or similar XXX */
+	return 0;
+}
+
+static int handle_mcast(struct vnet_port *port, void *msgbuf)
+{
+	struct vio_net_mcast_info *pkt = msgbuf;
+
+	if (pkt->tag.stype != VIO_SUBTYPE_ACK)
+		pr_err("%s: Got unexpected MCAST reply [%02x:%02x:%04x:%08x]\n",
+		       port->vp->dev->name,
+		       pkt->tag.type,
+		       pkt->tag.stype,
+		       pkt->tag.stype_env,
+		       pkt->tag.sid);
+
+	return 0;
+}
+
+/* Got back a STOPPED LDC message on port. If the queue is stopped,
+ * wake it up so that we'll send out another START message at the
+ * next TX.
+ */
+static void maybe_tx_wakeup(struct vnet_port *port)
+{
+	struct netdev_queue *txq;
+
+	txq = netdev_get_tx_queue(port->vp->dev, port->q_index);
+	__netif_tx_lock(txq, smp_processor_id());
+	if (likely(netif_tx_queue_stopped(txq))) {
+		struct vio_dring_state *dr;
+
+		dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+		netif_tx_wake_queue(txq);
+	}
+	__netif_tx_unlock(txq);
+}
+
+static inline bool port_is_up(struct vnet_port *vnet)
+{
+	struct vio_driver_state *vio = &vnet->vio;
+
+	return !!(vio->hs_state & VIO_HS_COMPLETE);
+}
+
+static int vnet_event_napi(struct vnet_port *port, int budget)
+{
+	struct vio_driver_state *vio = &port->vio;
+	int tx_wakeup, err;
+	int npkts = 0;
+	int event = (port->rx_event & LDC_EVENT_RESET);
+
+ldc_ctrl:
+	if (unlikely(event == LDC_EVENT_RESET ||
+		     event == LDC_EVENT_UP)) {
+		vio_link_state_change(vio, event);
+
+		if (event == LDC_EVENT_RESET) {
+			vnet_port_reset(port);
+			vio_port_up(vio);
+		}
+		port->rx_event = 0;
+		return 0;
+	}
+	/* We may have multiple LDC events in rx_event. Unroll send_events() */
+	event = (port->rx_event & LDC_EVENT_UP);
+	port->rx_event &= ~(LDC_EVENT_RESET|LDC_EVENT_UP);
+	if (event == LDC_EVENT_UP)
+		goto ldc_ctrl;
+	event = port->rx_event;
+	if (!(event & LDC_EVENT_DATA_READY))
+		return 0;
+
+	/* we dont expect any other bits than RESET, UP, DATA_READY */
+	BUG_ON(event != LDC_EVENT_DATA_READY);
+
+	tx_wakeup = err = 0;
+	while (1) {
+		union {
+			struct vio_msg_tag tag;
+			u64 raw[8];
+		} msgbuf;
+
+		if (port->napi_resume) {
+			struct vio_dring_data *pkt =
+				(struct vio_dring_data *)&msgbuf;
+			struct vio_dring_state *dr =
+				&port->vio.drings[VIO_DRIVER_RX_RING];
+
+			pkt->tag.type = VIO_TYPE_DATA;
+			pkt->tag.stype = VIO_SUBTYPE_INFO;
+			pkt->tag.stype_env = VIO_DRING_DATA;
+			pkt->seq = dr->rcv_nxt;
+			pkt->start_idx = vio_dring_next(dr, port->napi_stop_idx);
+			pkt->end_idx = -1;
+			goto napi_resume;
+		}
+		err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
+		if (unlikely(err < 0)) {
+			if (err == -ECONNRESET)
+				vio_conn_reset(vio);
+			break;
+		}
+		if (err == 0)
+			break;
+		viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
+		       msgbuf.tag.type,
+		       msgbuf.tag.stype,
+		       msgbuf.tag.stype_env,
+		       msgbuf.tag.sid);
+		err = vio_validate_sid(vio, &msgbuf.tag);
+		if (err < 0)
+			break;
+napi_resume:
+		if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
+			if (msgbuf.tag.stype == VIO_SUBTYPE_INFO) {
+				if (!port_is_up(port)) {
+					/* failures like handshake_failure()
+					 * may have cleaned up dring, but
+					 * NAPI polling may bring us here.
+					 */
+					err = -ECONNRESET;
+					break;
+				}
+				err = vnet_rx(port, &msgbuf, &npkts, budget);
+				if (npkts >= budget)
+					break;
+				if (npkts == 0)
+					break;
+			} else if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) {
+				err = vnet_ack(port, &msgbuf);
+				if (err > 0)
+					tx_wakeup |= err;
+			} else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) {
+				err = vnet_nack(port, &msgbuf);
+			}
+		} else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
+			if (msgbuf.tag.stype_env == VNET_MCAST_INFO)
+				err = handle_mcast(port, &msgbuf);
+			else
+				err = vio_control_pkt_engine(vio, &msgbuf);
+			if (err)
+				break;
+		} else {
+			err = vnet_handle_unknown(port, &msgbuf);
+		}
+		if (err == -ECONNRESET)
+			break;
+	}
+	if (unlikely(tx_wakeup && err != -ECONNRESET))
+		maybe_tx_wakeup(port);
+	return npkts;
+}
+
+int sunvnet_poll_common(struct napi_struct *napi, int budget)
+{
+	struct vnet_port *port = container_of(napi, struct vnet_port, napi);
+	struct vio_driver_state *vio = &port->vio;
+	int processed = vnet_event_napi(port, budget);
+
+	if (processed < budget) {
+		napi_complete(napi);
+		port->rx_event &= ~LDC_EVENT_DATA_READY;
+		vio_set_intr(vio->vdev->rx_ino, HV_INTR_ENABLED);
+	}
+	return processed;
+}
+EXPORT_SYMBOL_GPL(sunvnet_poll_common);
+
+void sunvnet_event_common(void *arg, int event)
+{
+	struct vnet_port *port = arg;
+	struct vio_driver_state *vio = &port->vio;
+
+	port->rx_event |= event;
+	vio_set_intr(vio->vdev->rx_ino, HV_INTR_DISABLED);
+	napi_schedule(&port->napi);
+
+}
+EXPORT_SYMBOL_GPL(sunvnet_event_common);
+
+static int __vnet_tx_trigger(struct vnet_port *port, u32 start)
+{
+	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+	struct vio_dring_data hdr = {
+		.tag = {
+			.type		= VIO_TYPE_DATA,
+			.stype		= VIO_SUBTYPE_INFO,
+			.stype_env	= VIO_DRING_DATA,
+			.sid		= vio_send_sid(&port->vio),
+		},
+		.dring_ident		= dr->ident,
+		.start_idx		= start,
+		.end_idx		= (u32) -1,
+	};
+	int err, delay;
+	int retries = 0;
+
+	if (port->stop_rx) {
+		trace_vnet_tx_pending_stopped_ack(port->vio._local_sid,
+						  port->vio._peer_sid,
+						  port->stop_rx_idx, -1);
+		err = vnet_send_ack(port,
+				    &port->vio.drings[VIO_DRIVER_RX_RING],
+				    port->stop_rx_idx, -1,
+				    VIO_DRING_STOPPED);
+		if (err <= 0)
+			return err;
+	}
+
+	hdr.seq = dr->snd_nxt;
+	delay = 1;
+	do {
+		err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
+		if (err > 0) {
+			dr->snd_nxt++;
+			break;
+		}
+		udelay(delay);
+		if ((delay <<= 1) > 128)
+			delay = 128;
+		if (retries++ > VNET_MAX_RETRIES)
+			break;
+	} while (err == -EAGAIN);
+	trace_vnet_tx_trigger(port->vio._local_sid,
+			      port->vio._peer_sid, start, err);
+
+	return err;
+}
+
+static struct vnet_port *__tx_port_find(struct vnet *vp, struct sk_buff *skb)
+{
+	unsigned int hash = vnet_hashfn(skb->data);
+	struct hlist_head *hp = &vp->port_hash[hash];
+	struct vnet_port *port;
+
+	hlist_for_each_entry_rcu(port, hp, hash) {
+		if (!port_is_up(port))
+			continue;
+		if (ether_addr_equal(port->raddr, skb->data))
+			return port;
+	}
+	list_for_each_entry_rcu(port, &vp->port_list, list) {
+		if (!port->switch_port)
+			continue;
+		if (!port_is_up(port))
+			continue;
+		return port;
+	}
+	return NULL;
+}
+
+static struct sk_buff *vnet_clean_tx_ring(struct vnet_port *port,
+					  unsigned *pending)
+{
+	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+	struct sk_buff *skb = NULL;
+	int i, txi;
+
+	*pending = 0;
+
+	txi = dr->prod;
+	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
+		struct vio_net_desc *d;
+
+		--txi;
+		if (txi < 0)
+			txi = VNET_TX_RING_SIZE-1;
+
+		d = vio_dring_entry(dr, txi);
+
+		if (d->hdr.state == VIO_DESC_READY) {
+			(*pending)++;
+			continue;
+		}
+		if (port->tx_bufs[txi].skb) {
+			if (d->hdr.state != VIO_DESC_DONE)
+				pr_notice("invalid ring buffer state %d\n",
+					  d->hdr.state);
+			BUG_ON(port->tx_bufs[txi].skb->next);
+
+			port->tx_bufs[txi].skb->next = skb;
+			skb = port->tx_bufs[txi].skb;
+			port->tx_bufs[txi].skb = NULL;
+
+			ldc_unmap(port->vio.lp,
+				  port->tx_bufs[txi].cookies,
+				  port->tx_bufs[txi].ncookies);
+		} else if (d->hdr.state == VIO_DESC_FREE)
+			break;
+		d->hdr.state = VIO_DESC_FREE;
+	}
+	return skb;
+}
+
+static inline void vnet_free_skbs(struct sk_buff *skb)
+{
+	struct sk_buff *next;
+
+	while (skb) {
+		next = skb->next;
+		skb->next = NULL;
+		dev_kfree_skb(skb);
+		skb = next;
+	}
+}
+
+void sunvnet_clean_timer_expire_common(unsigned long port0)
+{
+	struct vnet_port *port = (struct vnet_port *)port0;
+	struct sk_buff *freeskbs;
+	unsigned pending;
+
+	netif_tx_lock(port->vp->dev);
+	freeskbs = vnet_clean_tx_ring(port, &pending);
+	netif_tx_unlock(port->vp->dev);
+
+	vnet_free_skbs(freeskbs);
+
+	if (pending)
+		(void)mod_timer(&port->clean_timer,
+				jiffies + VNET_CLEAN_TIMEOUT);
+	 else
+		del_timer(&port->clean_timer);
+}
+EXPORT_SYMBOL_GPL(sunvnet_clean_timer_expire_common);
+
+static inline int vnet_skb_map(struct ldc_channel *lp, struct sk_buff *skb,
+			       struct ldc_trans_cookie *cookies, int ncookies,
+			       unsigned int map_perm)
+{
+	int i, nc, err, blen;
+
+	/* header */
+	blen = skb_headlen(skb);
+	if (blen < ETH_ZLEN)
+		blen = ETH_ZLEN;
+	blen += VNET_PACKET_SKIP;
+	blen += 8 - (blen & 7);
+
+	err = ldc_map_single(lp, skb->data-VNET_PACKET_SKIP, blen, cookies,
+			     ncookies, map_perm);
+	if (err < 0)
+		return err;
+	nc = err;
+
+	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
+		u8 *vaddr;
+
+		if (nc < ncookies) {
+			vaddr = kmap_atomic(skb_frag_page(f));
+			blen = skb_frag_size(f);
+			blen += 8 - (blen & 7);
+			err = ldc_map_single(lp, vaddr + f->page_offset,
+					     blen, cookies + nc, ncookies - nc,
+					     map_perm);
+			kunmap_atomic(vaddr);
+		} else {
+			err = -EMSGSIZE;
+		}
+
+		if (err < 0) {
+			ldc_unmap(lp, cookies, nc);
+			return err;
+		}
+		nc += err;
+	}
+	return nc;
+}
+
+static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, int ncookies)
+{
+	struct sk_buff *nskb;
+	int i, len, pad, docopy;
+
+	len = skb->len;
+	pad = 0;
+	if (len < ETH_ZLEN) {
+		pad += ETH_ZLEN - skb->len;
+		len += pad;
+	}
+	len += VNET_PACKET_SKIP;
+	pad += 8 - (len & 7);
+
+	/* make sure we have enough cookies and alignment in every frag */
+	docopy = skb_shinfo(skb)->nr_frags >= ncookies;
+	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+		skb_frag_t *f = &skb_shinfo(skb)->frags[i];
+
+		docopy |= f->page_offset & 7;
+	}
+	if (((unsigned long)skb->data & 7) != VNET_PACKET_SKIP ||
+	    skb_tailroom(skb) < pad ||
+	    skb_headroom(skb) < VNET_PACKET_SKIP || docopy) {
+		int start = 0, offset;
+		__wsum csum;
+
+		len = skb->len > ETH_ZLEN ? skb->len : ETH_ZLEN;
+		nskb = alloc_and_align_skb(skb->dev, len);
+		if (nskb == NULL) {
+			dev_kfree_skb(skb);
+			return NULL;
+		}
+		skb_reserve(nskb, VNET_PACKET_SKIP);
+
+		nskb->protocol = skb->protocol;
+		offset = skb_mac_header(skb) - skb->data;
+		skb_set_mac_header(nskb, offset);
+		offset = skb_network_header(skb) - skb->data;
+		skb_set_network_header(nskb, offset);
+		offset = skb_transport_header(skb) - skb->data;
+		skb_set_transport_header(nskb, offset);
+
+		offset = 0;
+		nskb->csum_offset = skb->csum_offset;
+		nskb->ip_summed = skb->ip_summed;
+
+		if (skb->ip_summed == CHECKSUM_PARTIAL)
+			start = skb_checksum_start_offset(skb);
+		if (start) {
+			struct iphdr *iph = ip_hdr(nskb);
+			int offset = start + nskb->csum_offset;
+
+			if (skb_copy_bits(skb, 0, nskb->data, start)) {
+				dev_kfree_skb(nskb);
+				dev_kfree_skb(skb);
+				return NULL;
+			}
+			*(__sum16 *)(skb->data + offset) = 0;
+			csum = skb_copy_and_csum_bits(skb, start,
+						      nskb->data + start,
+						      skb->len - start, 0);
+			if (iph->protocol == IPPROTO_TCP ||
+			    iph->protocol == IPPROTO_UDP) {
+				csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
+							 skb->len - start,
+							 iph->protocol, csum);
+			}
+			*(__sum16 *)(nskb->data + offset) = csum;
+
+			nskb->ip_summed = CHECKSUM_NONE;
+		} else if (skb_copy_bits(skb, 0, nskb->data, skb->len)) {
+			dev_kfree_skb(nskb);
+			dev_kfree_skb(skb);
+			return NULL;
+		}
+		(void)skb_put(nskb, skb->len);
+		if (skb_is_gso(skb)) {
+			skb_shinfo(nskb)->gso_size = skb_shinfo(skb)->gso_size;
+			skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
+		}
+		nskb->queue_mapping = skb->queue_mapping;
+		dev_kfree_skb(skb);
+		skb = nskb;
+	}
+	return skb;
+}
+
+u16 sunvnet_select_queue_common(struct net_device *dev, struct sk_buff *skb,
+		  void *accel_priv, select_queue_fallback_t fallback)
+{
+	struct vnet *vp = netdev_priv(dev);
+	struct vnet_port *port = __tx_port_find(vp, skb);
+
+	if (port == NULL)
+		return 0;
+	return port->q_index;
+}
+EXPORT_SYMBOL_GPL(sunvnet_select_queue_common);
+
+static int vnet_handle_offloads(struct vnet_port *port, struct sk_buff *skb)
+{
+	struct net_device *dev = port->vp->dev;
+	struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+	struct sk_buff *segs;
+	int maclen, datalen;
+	int status;
+	int gso_size, gso_type, gso_segs;
+	int hlen = skb_transport_header(skb) - skb_mac_header(skb);
+	int proto = IPPROTO_IP;
+
+	if (skb->protocol == htons(ETH_P_IP))
+		proto = ip_hdr(skb)->protocol;
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		proto = ipv6_hdr(skb)->nexthdr;
+
+	if (proto == IPPROTO_TCP)
+		hlen += tcp_hdr(skb)->doff * 4;
+	else if (proto == IPPROTO_UDP)
+		hlen += sizeof(struct udphdr);
+	else {
+		pr_err("vnet_handle_offloads GSO with unknown transport "
+		       "protocol %d tproto %d\n", skb->protocol, proto);
+		hlen = 128; /* XXX */
+	}
+	datalen = port->tsolen - hlen;
+
+	gso_size = skb_shinfo(skb)->gso_size;
+	gso_type = skb_shinfo(skb)->gso_type;
+	gso_segs = skb_shinfo(skb)->gso_segs;
+
+	if (port->tso && gso_size < datalen)
+		gso_segs = DIV_ROUND_UP(skb->len - hlen, datalen);
+
+	if (unlikely(vnet_tx_dring_avail(dr) < gso_segs)) {
+		struct netdev_queue *txq;
+
+		txq  = netdev_get_tx_queue(dev, port->q_index);
+		netif_tx_stop_queue(txq);
+		if (vnet_tx_dring_avail(dr) < skb_shinfo(skb)->gso_segs)
+			return NETDEV_TX_BUSY;
+		netif_tx_wake_queue(txq);
+	}
+
+	maclen = skb_network_header(skb) - skb_mac_header(skb);
+	skb_pull(skb, maclen);
+
+	if (port->tso && gso_size < datalen) {
+		if (skb_unclone(skb, GFP_ATOMIC))
+			goto out_dropped;
+
+		/* segment to TSO size */
+		skb_shinfo(skb)->gso_size = datalen;
+		skb_shinfo(skb)->gso_segs = gso_segs;
+	}
+	segs = skb_gso_segment(skb, dev->features & ~NETIF_F_TSO);
+	if (IS_ERR(segs))
+		goto out_dropped;
+
+	skb_push(skb, maclen);
+	skb_reset_mac_header(skb);
+
+	status = 0;
+	while (segs) {
+		struct sk_buff *curr = segs;
+
+		segs = segs->next;
+		curr->next = NULL;
+		if (port->tso && curr->len > dev->mtu) {
+			skb_shinfo(curr)->gso_size = gso_size;
+			skb_shinfo(curr)->gso_type = gso_type;
+			skb_shinfo(curr)->gso_segs =
+				DIV_ROUND_UP(curr->len - hlen, gso_size);
+		} else
+			skb_shinfo(curr)->gso_size = 0;
+
+		skb_push(curr, maclen);
+		skb_reset_mac_header(curr);
+		memcpy(skb_mac_header(curr), skb_mac_header(skb),
+		       maclen);
+		curr->csum_start = skb_transport_header(curr) - curr->head;
+		if (ip_hdr(curr)->protocol == IPPROTO_TCP)
+			curr->csum_offset = offsetof(struct tcphdr, check);
+		else if (ip_hdr(curr)->protocol == IPPROTO_UDP)
+			curr->csum_offset = offsetof(struct udphdr, check);
+
+		if (!(status & NETDEV_TX_MASK))
+			status = sunvnet_start_xmit_common(curr, dev);
+		if (status & NETDEV_TX_MASK)
+			dev_kfree_skb_any(curr);
+	}
+
+	if (!(status & NETDEV_TX_MASK))
+		dev_kfree_skb_any(skb);
+	return status;
+out_dropped:
+	dev->stats.tx_dropped++;
+	dev_kfree_skb_any(skb);
+	return NETDEV_TX_OK;
+}
+
+int sunvnet_start_xmit_common(struct sk_buff *skb, struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+	struct vnet_port *port = NULL;
+	struct vio_dring_state *dr;
+	struct vio_net_desc *d;
+	unsigned int len;
+	struct sk_buff *freeskbs = NULL;
+	int i, err, txi;
+	unsigned pending = 0;
+	struct netdev_queue *txq;
+
+	rcu_read_lock();
+	port = __tx_port_find(vp, skb);
+	if (unlikely(!port)) {
+		rcu_read_unlock();
+		goto out_dropped;
+	}
+
+	if (skb_is_gso(skb) && skb->len > port->tsolen) {
+		err = vnet_handle_offloads(port, skb);
+		rcu_read_unlock();
+		return err;
+	}
+
+	if (!skb_is_gso(skb) && skb->len > port->rmtu) {
+		unsigned long localmtu = port->rmtu - ETH_HLEN;
+
+		if (vio_version_after_eq(&port->vio, 1, 3))
+			localmtu -= VLAN_HLEN;
+
+		if (skb->protocol == htons(ETH_P_IP)) {
+			struct flowi4 fl4;
+			struct rtable *rt = NULL;
+
+			memset(&fl4, 0, sizeof(fl4));
+			fl4.flowi4_oif = dev->ifindex;
+			fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
+			fl4.daddr = ip_hdr(skb)->daddr;
+			fl4.saddr = ip_hdr(skb)->saddr;
+
+			rt = ip_route_output_key(dev_net(dev), &fl4);
+			rcu_read_unlock();
+			if (!IS_ERR(rt)) {
+				skb_dst_set(skb, &rt->dst);
+				icmp_send(skb, ICMP_DEST_UNREACH,
+					  ICMP_FRAG_NEEDED,
+					  htonl(localmtu));
+			}
+		}
+#if IS_ENABLED(CONFIG_IPV6)
+		else if (skb->protocol == htons(ETH_P_IPV6))
+			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, localmtu);
+#endif
+		goto out_dropped;
+	}
+
+	skb = vnet_skb_shape(skb, 2);
+
+	if (unlikely(!skb))
+		goto out_dropped;
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL)
+		vnet_fullcsum(skb);
+
+	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+	i = skb_get_queue_mapping(skb);
+	txq = netdev_get_tx_queue(dev, i);
+	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
+		if (!netif_tx_queue_stopped(txq)) {
+			netif_tx_stop_queue(txq);
+
+			/* This is a hard error, log it. */
+			netdev_err(dev, "BUG! Tx Ring full when queue awake!\n");
+			dev->stats.tx_errors++;
+		}
+		rcu_read_unlock();
+		return NETDEV_TX_BUSY;
+	}
+
+	d = vio_dring_cur(dr);
+
+	txi = dr->prod;
+
+	freeskbs = vnet_clean_tx_ring(port, &pending);
+
+	BUG_ON(port->tx_bufs[txi].skb);
+
+	len = skb->len;
+	if (len < ETH_ZLEN)
+		len = ETH_ZLEN;
+
+	err = vnet_skb_map(port->vio.lp, skb, port->tx_bufs[txi].cookies, 2,
+			   (LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_RW));
+	if (err < 0) {
+		netdev_info(dev, "tx buffer map error %d\n", err);
+		goto out_dropped;
+	}
+
+	port->tx_bufs[txi].skb = skb;
+	skb = NULL;
+	port->tx_bufs[txi].ncookies = err;
+
+	/* We don't rely on the ACKs to free the skb in vnet_start_xmit(),
+	 * thus it is safe to not set VIO_ACK_ENABLE for each transmission:
+	 * the protocol itself does not require it as long as the peer
+	 * sends a VIO_SUBTYPE_ACK for VIO_DRING_STOPPED.
+	 *
+	 * An ACK for every packet in the ring is expensive as the
+	 * sending of LDC messages is slow and affects performance.
+	 */
+	d->hdr.ack = VIO_ACK_DISABLE;
+	d->size = len;
+	d->ncookies = port->tx_bufs[txi].ncookies;
+	for (i = 0; i < d->ncookies; i++)
+		d->cookies[i] = port->tx_bufs[txi].cookies[i];
+	if (vio_version_after_eq(&port->vio, 1, 7)) {
+		struct vio_net_dext *dext = vio_net_ext(d);
+
+		memset(dext, 0, sizeof(*dext));
+		if (skb_is_gso(port->tx_bufs[txi].skb)) {
+			dext->ipv4_lso_mss = skb_shinfo(port->tx_bufs[txi].skb)
+					     ->gso_size;
+			dext->flags |= VNET_PKT_IPV4_LSO;
+		}
+		if (vio_version_after_eq(&port->vio, 1, 8) &&
+		    !port->switch_port) {
+			dext->flags |= VNET_PKT_HCK_IPV4_HDRCKSUM_OK;
+			dext->flags |= VNET_PKT_HCK_FULLCKSUM_OK;
+		}
+	}
+
+	/* This has to be a non-SMP write barrier because we are writing
+	 * to memory which is shared with the peer LDOM.
+	 */
+	dma_wmb();
+
+	d->hdr.state = VIO_DESC_READY;
+
+	/* Exactly one ldc "start" trigger (for dr->cons) needs to be sent
+	 * to notify the consumer that some descriptors are READY.
+	 * After that "start" trigger, no additional triggers are needed until
+	 * a DRING_STOPPED is received from the consumer. The dr->cons field
+	 * (set up by vnet_ack()) has the value of the next dring index
+	 * that has not yet been ack-ed. We send a "start" trigger here
+	 * if, and only if, start_cons is true (reset it afterward). Conversely,
+	 * vnet_ack() should check if the dring corresponding to cons
+	 * is marked READY, but start_cons was false.
+	 * If so, vnet_ack() should send out the missed "start" trigger.
+	 *
+	 * Note that the dma_wmb() above makes sure the cookies et al. are
+	 * not globally visible before the VIO_DESC_READY, and that the
+	 * stores are ordered correctly by the compiler. The consumer will
+	 * not proceed until the VIO_DESC_READY is visible assuring that
+	 * the consumer does not observe anything related to descriptors
+	 * out of order. The HV trap from the LDC start trigger is the
+	 * producer to consumer announcement that work is available to the
+	 * consumer
+	 */
+	if (!port->start_cons) { /* previous trigger suffices */
+		trace_vnet_skip_tx_trigger(port->vio._local_sid,
+					   port->vio._peer_sid, dr->cons);
+		goto ldc_start_done;
+	}
+
+	err = __vnet_tx_trigger(port, dr->cons);
+	if (unlikely(err < 0)) {
+		netdev_info(dev, "TX trigger error %d\n", err);
+		d->hdr.state = VIO_DESC_FREE;
+		skb = port->tx_bufs[txi].skb;
+		port->tx_bufs[txi].skb = NULL;
+		dev->stats.tx_carrier_errors++;
+		goto out_dropped;
+	}
+
+ldc_start_done:
+	port->start_cons = false;
+
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += port->tx_bufs[txi].skb->len;
+
+	dr->prod = (dr->prod + 1) & (VNET_TX_RING_SIZE - 1);
+	if (unlikely(vnet_tx_dring_avail(dr) < 1)) {
+		netif_tx_stop_queue(txq);
+		if (vnet_tx_dring_avail(dr) > VNET_TX_WAKEUP_THRESH(dr))
+			netif_tx_wake_queue(txq);
+	}
+
+	(void)mod_timer(&port->clean_timer, jiffies + VNET_CLEAN_TIMEOUT);
+	rcu_read_unlock();
+
+	vnet_free_skbs(freeskbs);
+
+	return NETDEV_TX_OK;
+
+out_dropped:
+	if (pending)
+		(void)mod_timer(&port->clean_timer,
+				jiffies + VNET_CLEAN_TIMEOUT);
+	else if (port)
+		del_timer(&port->clean_timer);
+	if (port)
+		rcu_read_unlock();
+	if (skb)
+		dev_kfree_skb(skb);
+	vnet_free_skbs(freeskbs);
+	dev->stats.tx_dropped++;
+	return NETDEV_TX_OK;
+}
+EXPORT_SYMBOL_GPL(sunvnet_start_xmit_common);
+
+void sunvnet_tx_timeout_common(struct net_device *dev)
+{
+	/* XXX Implement me XXX */
+}
+EXPORT_SYMBOL_GPL(sunvnet_tx_timeout_common);
+
+int sunvnet_open_common(struct net_device *dev)
+{
+	netif_carrier_on(dev);
+	netif_tx_start_all_queues(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sunvnet_open_common);
+
+int sunvnet_close_common(struct net_device *dev)
+{
+	netif_tx_stop_all_queues(dev);
+	netif_carrier_off(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sunvnet_close_common);
+
+static struct vnet_mcast_entry *__vnet_mc_find(struct vnet *vp, u8 *addr)
+{
+	struct vnet_mcast_entry *m;
+
+	for (m = vp->mcast_list; m; m = m->next) {
+		if (ether_addr_equal(m->addr, addr))
+			return m;
+	}
+	return NULL;
+}
+
+static void __update_mc_list(struct vnet *vp, struct net_device *dev)
+{
+	struct netdev_hw_addr *ha;
+
+	netdev_for_each_mc_addr(ha, dev) {
+		struct vnet_mcast_entry *m;
+
+		m = __vnet_mc_find(vp, ha->addr);
+		if (m) {
+			m->hit = 1;
+			continue;
+		}
+
+		if (!m) {
+			m = kzalloc(sizeof(*m), GFP_ATOMIC);
+			if (!m)
+				continue;
+			memcpy(m->addr, ha->addr, ETH_ALEN);
+			m->hit = 1;
+
+			m->next = vp->mcast_list;
+			vp->mcast_list = m;
+		}
+	}
+}
+
+static void __send_mc_list(struct vnet *vp, struct vnet_port *port)
+{
+	struct vio_net_mcast_info info;
+	struct vnet_mcast_entry *m, **pp;
+	int n_addrs;
+
+	memset(&info, 0, sizeof(info));
+
+	info.tag.type = VIO_TYPE_CTRL;
+	info.tag.stype = VIO_SUBTYPE_INFO;
+	info.tag.stype_env = VNET_MCAST_INFO;
+	info.tag.sid = vio_send_sid(&port->vio);
+	info.set = 1;
+
+	n_addrs = 0;
+	for (m = vp->mcast_list; m; m = m->next) {
+		if (m->sent)
+			continue;
+		m->sent = 1;
+		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
+		       m->addr, ETH_ALEN);
+		if (++n_addrs == VNET_NUM_MCAST) {
+			info.count = n_addrs;
+
+			(void) vio_ldc_send(&port->vio, &info,
+					    sizeof(info));
+			n_addrs = 0;
+		}
+	}
+	if (n_addrs) {
+		info.count = n_addrs;
+		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
+	}
+
+	info.set = 0;
+
+	n_addrs = 0;
+	pp = &vp->mcast_list;
+	while ((m = *pp) != NULL) {
+		if (m->hit) {
+			m->hit = 0;
+			pp = &m->next;
+			continue;
+		}
+
+		memcpy(&info.mcast_addr[n_addrs * ETH_ALEN],
+		       m->addr, ETH_ALEN);
+		if (++n_addrs == VNET_NUM_MCAST) {
+			info.count = n_addrs;
+			(void) vio_ldc_send(&port->vio, &info,
+					    sizeof(info));
+			n_addrs = 0;
+		}
+
+		*pp = m->next;
+		kfree(m);
+	}
+	if (n_addrs) {
+		info.count = n_addrs;
+		(void) vio_ldc_send(&port->vio, &info, sizeof(info));
+	}
+}
+
+void sunvnet_set_rx_mode_common(struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+	struct vnet_port *port;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(port, &vp->port_list, list) {
+
+		if (port->switch_port) {
+			__update_mc_list(vp, dev);
+			__send_mc_list(vp, port);
+			break;
+		}
+	}
+	rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(sunvnet_set_rx_mode_common);
+
+int sunvnet_change_mtu_common(struct net_device *dev, int new_mtu)
+{
+	if (new_mtu < 68 || new_mtu > 65535)
+		return -EINVAL;
+
+	dev->mtu = new_mtu;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sunvnet_change_mtu_common);
+
+int sunvnet_set_mac_addr_common(struct net_device *dev, void *p)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(sunvnet_set_mac_addr_common);
+
+void sunvnet_port_free_tx_bufs_common(struct vnet_port *port)
+{
+	struct vio_dring_state *dr;
+	int i;
+
+	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+
+	if (dr->base == NULL)
+		return;
+
+	for (i = 0; i < VNET_TX_RING_SIZE; i++) {
+		struct vio_net_desc *d;
+		void *skb = port->tx_bufs[i].skb;
+
+		if (!skb)
+			continue;
+
+		d = vio_dring_entry(dr, i);
+
+		ldc_unmap(port->vio.lp,
+			  port->tx_bufs[i].cookies,
+			  port->tx_bufs[i].ncookies);
+		dev_kfree_skb(skb);
+		port->tx_bufs[i].skb = NULL;
+		d->hdr.state = VIO_DESC_FREE;
+	}
+	ldc_free_exp_dring(port->vio.lp, dr->base,
+			   (dr->entry_size * dr->num_entries),
+			   dr->cookies, dr->ncookies);
+	dr->base = NULL;
+	dr->entry_size = 0;
+	dr->num_entries = 0;
+	dr->pending = 0;
+	dr->ncookies = 0;
+}
+EXPORT_SYMBOL_GPL(sunvnet_port_free_tx_bufs_common);
+
+static void vnet_port_reset(struct vnet_port *port)
+{
+	del_timer(&port->clean_timer);
+	sunvnet_port_free_tx_bufs_common(port);
+	port->rmtu = 0;
+	port->tso = true;
+	port->tsolen = 0;
+}
+
+static int vnet_port_alloc_tx_ring(struct vnet_port *port)
+{
+	struct vio_dring_state *dr;
+	unsigned long len, elen;
+	int i, err, ncookies;
+	void *dring;
+
+	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
+
+	elen = sizeof(struct vio_net_desc) +
+	       sizeof(struct ldc_trans_cookie) * 2;
+	if (vio_version_after_eq(&port->vio, 1, 7))
+		elen += sizeof(struct vio_net_dext);
+	len = VNET_TX_RING_SIZE * elen;
+
+	ncookies = VIO_MAX_RING_COOKIES;
+	dring = ldc_alloc_exp_dring(port->vio.lp, len,
+				    dr->cookies, &ncookies,
+				    (LDC_MAP_SHADOW |
+				     LDC_MAP_DIRECT |
+				     LDC_MAP_RW));
+	if (IS_ERR(dring)) {
+		err = PTR_ERR(dring);
+		goto err_out;
+	}
+
+	dr->base = dring;
+	dr->entry_size = elen;
+	dr->num_entries = VNET_TX_RING_SIZE;
+	dr->prod = dr->cons = 0;
+	port->start_cons  = true; /* need an initial trigger */
+	dr->pending = VNET_TX_RING_SIZE;
+	dr->ncookies = ncookies;
+
+	for (i = 0; i < VNET_TX_RING_SIZE; ++i) {
+		struct vio_net_desc *d;
+
+		d = vio_dring_entry(dr, i);
+		d->hdr.state = VIO_DESC_FREE;
+	}
+	return 0;
+
+err_out:
+	sunvnet_port_free_tx_bufs_common(port);
+
+	return err;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+void sunvnet_poll_controller_common(struct net_device *dev)
+{
+	struct vnet *vp = netdev_priv(dev);
+	struct vnet_port *port;
+	unsigned long flags;
+
+	spin_lock_irqsave(&vp->lock, flags);
+	if (!list_empty(&vp->port_list)) {
+		port = list_entry(vp->port_list.next, struct vnet_port, list);
+		napi_schedule(&port->napi);
+	}
+	spin_unlock_irqrestore(&vp->lock, flags);
+}
+EXPORT_SYMBOL_GPL(sunvnet_poll_controller_common);
+#endif
+
+void sunvnet_port_add_txq_common(struct vnet_port *port)
+{
+	struct vnet *vp = port->vp;
+	int n;
+
+	n = vp->nports++;
+	n = n & (VNET_MAX_TXQS - 1);
+	port->q_index = n;
+	netif_tx_wake_queue(netdev_get_tx_queue(vp->dev, port->q_index));
+}
+EXPORT_SYMBOL_GPL(sunvnet_port_add_txq_common);
+
+void sunvnet_port_rm_txq_common(struct vnet_port *port)
+{
+	port->vp->nports--;
+	netif_tx_stop_queue(netdev_get_tx_queue(port->vp->dev, port->q_index));
+}
+EXPORT_SYMBOL_GPL(sunvnet_port_rm_txq_common);
diff --git a/drivers/net/ethernet/sun/sunvnet.h b/drivers/net/ethernet/sun/sunvnet_common.h
index 01ca78191683..c29c5269703d 100644
--- a/drivers/net/ethernet/sun/sunvnet.h
+++ b/drivers/net/ethernet/sun/sunvnet_common.h
@@ -1,20 +1,12 @@
-#ifndef _SUNVNET_H
-#define _SUNVNET_H
+#ifndef _SUNVNETCOMMON_H
+#define _SUNVNETCOMMON_H
 
 #include <linux/interrupt.h>
 
-#define DESC_NCOOKIES(entry_size)	\
-	((entry_size) - sizeof(struct vio_net_desc))
-
-/* length of time before we decide the hardware is borked,
- * and dev->tx_timeout() should be called to fix the problem
- */
-#define VNET_TX_TIMEOUT			(5 * HZ)
-
 /* length of time (or less) we expect pending descriptors to be marked
  * as VIO_DESC_DONE and skbs ready to be freed
  */
-#define	VNET_CLEAN_TIMEOUT		((HZ/100)+1)
+#define	VNET_CLEAN_TIMEOUT		((HZ / 100) + 1)
 
 #define VNET_MAXPACKET			(65535ULL + ETH_HLEN + VLAN_HLEN)
 #define VNET_TX_RING_SIZE		512
@@ -29,7 +21,9 @@
  */
 #define VNET_PACKET_SKIP		6
 
-#define VNET_MAXCOOKIES			(VNET_MAXPACKET/PAGE_SIZE + 1)
+#define	VNET_MAXCOOKIES			(VNET_MAXPACKET / PAGE_SIZE + 1)
+
+#define	VNET_MAX_TXQS		16
 
 struct vnet_tx_entry {
 	struct sk_buff		*skb;
@@ -111,4 +105,29 @@ struct vnet {
 	int			nports;
 };
 
-#endif /* _SUNVNET_H */
+/* Common funcs */
+void sunvnet_clean_timer_expire_common(unsigned long port0);
+int sunvnet_open_common(struct net_device *dev);
+int sunvnet_close_common(struct net_device *dev);
+void sunvnet_set_rx_mode_common(struct net_device *dev);
+int sunvnet_set_mac_addr_common(struct net_device *dev, void *p);
+void sunvnet_tx_timeout_common(struct net_device *dev);
+int sunvnet_change_mtu_common(struct net_device *dev, int new_mtu);
+int sunvnet_start_xmit_common(struct sk_buff *skb, struct net_device *dev);
+u16 sunvnet_select_queue_common(struct net_device *dev,
+				struct sk_buff *skb,
+				void *accel_priv,
+				select_queue_fallback_t fallback);
+#ifdef CONFIG_NET_POLL_CONTROLLER
+void sunvnet_poll_controller_common(struct net_device *dev);
+#endif
+void sunvnet_event_common(void *arg, int event);
+int sunvnet_send_attr_common(struct vio_driver_state *vio);
+int sunvnet_handle_attr_common(struct vio_driver_state *vio, void *arg);
+void sunvnet_handshake_complete_common(struct vio_driver_state *vio);
+int sunvnet_poll_common(struct napi_struct *napi, int budget);
+void sunvnet_port_free_tx_bufs_common(struct vnet_port *port);
+void sunvnet_port_add_txq_common(struct vnet_port *port);
+void sunvnet_port_rm_txq_common(struct vnet_port *port);
+
+#endif /* _SUNVNETCOMMON_H */