Clone Kip's Xen on stable/6 tree so that I can work on improving FreeBSD/amd64

performance in Xen's HVM mode.

1 files changed, 0 insertions, 1850 deletions

diff --git a/sys/dev/xen/netfront/netfront.c b/sys/dev/xen/netfront/netfront.c
deleted file mode 100644
index 3a29ffb..0000000
--- a/sys/dev/xen/netfront/netfront.c
+++ /dev/null
@@ -1,1850 +0,0 @@
-/*
- *
- * Copyright (c) 2004-2006 Kip Macy
- * All rights reserved.
- *
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/sockio.h>
-#include <sys/mbuf.h>
-#include <sys/malloc.h>
-#include <sys/kernel.h>
-#include <sys/socket.h>
-#include <sys/queue.h>
-#include <sys/lock.h>
-#include <sys/sx.h>
-
-#include <net/if.h>
-#include <net/if_arp.h>
-#include <net/ethernet.h>
-#include <net/if_dl.h>
-#include <net/if_media.h>
-
-#include <net/bpf.h>
-
-#include <net/if_types.h>
-#include <net/if.h>
-
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/if_ether.h>
-
-#include <vm/vm.h>
-#include <vm/pmap.h>
-
-#include <machine/clock.h>      /* for DELAY */
-#include <machine/bus.h>
-#include <machine/resource.h>
-#include <machine/frame.h>
-#include <machine/vmparam.h>
-
-#include <sys/bus.h>
-#include <sys/rman.h>
-
-#include <machine/intr_machdep.h>
-
-#include <machine/xen/xen-os.h>
-#include <machine/xen/hypervisor.h>
-#include <machine/xen/xen_intr.h>
-#include <machine/xen/evtchn.h>
-#include <machine/xen/xenbus.h>
-#include <xen/gnttab.h>
-#include <xen/interface/memory.h>
-#include <dev/xen/netfront/mbufq.h>
-#include <machine/xen/features.h>
-#include <xen/interface/io/netif.h>
-
-
-#define GRANT_INVALID_REF	0
-
-#define NET_TX_RING_SIZE __RING_SIZE((netif_tx_sring_t *)0, PAGE_SIZE)
-#define NET_RX_RING_SIZE __RING_SIZE((netif_rx_sring_t *)0, PAGE_SIZE)
-
-#ifdef CONFIG_XEN
-static int MODPARM_rx_copy = 0;
-module_param_named(rx_copy, MODPARM_rx_copy, bool, 0);
-MODULE_PARM_DESC(rx_copy, "Copy packets from network card (rather than flip)");
-static int MODPARM_rx_flip = 0;
-module_param_named(rx_flip, MODPARM_rx_flip, bool, 0);
-MODULE_PARM_DESC(rx_flip, "Flip packets from network card (rather than copy)");
-#else
-static const int MODPARM_rx_copy = 1;
-static const int MODPARM_rx_flip = 0;
-#endif
-
-#define RX_COPY_THRESHOLD 256
-
-#define net_ratelimit() 0
-
-struct netfront_info;
-struct netfront_rx_info;
-
-static void xn_txeof(struct netfront_info *);
-static void xn_rxeof(struct netfront_info *);
-static void network_alloc_rx_buffers(struct netfront_info *);
-
-static void xn_tick_locked(struct netfront_info *);
-static void xn_tick(void *);
-
-static void xn_intr(void *);
-static void xn_start_locked(struct ifnet *);
-static void xn_start(struct ifnet *);
-static int  xn_ioctl(struct ifnet *, u_long, caddr_t);
-static void xn_ifinit_locked(struct netfront_info *);
-static void xn_ifinit(void *);
-static void xn_stop(struct netfront_info *);
-#ifdef notyet
-static void xn_watchdog(struct ifnet *);
-#endif
-
-static void show_device(struct netfront_info *sc);
-#ifdef notyet
-static void netfront_closing(struct xenbus_device *dev);
-#endif
-static void netif_free(struct netfront_info *info);
-static int netfront_remove(struct xenbus_device *dev);
-
-static int talk_to_backend(struct xenbus_device *dev, struct netfront_info *info);
-static int create_netdev(struct xenbus_device *dev, struct ifnet **ifp);
-static void netif_disconnect_backend(struct netfront_info *info);
-static int setup_device(struct xenbus_device *dev, struct netfront_info *info);
-static void end_access(int ref, void *page);
-
-/* Xenolinux helper functions */
-static int network_connect(struct ifnet *ifp);
-
-static void xn_free_rx_ring(struct netfront_info *);
-
-static void xn_free_tx_ring(struct netfront_info *);
-
-static int xennet_get_responses(struct netfront_info *np,
-	struct netfront_rx_info *rinfo, RING_IDX rp, struct mbuf **list,
-	int *pages_flipped_p);
-
-#define virt_to_mfn(x) (vtomach(x) >> PAGE_SHIFT)
-
-#define INVALID_P2M_ENTRY (~0UL)
-
-/*
- * Mbuf pointers. We need these to keep track of the virtual addresses
- * of our mbuf chains since we can only convert from virtual to physical,
- * not the other way around.  The size must track the free index arrays.
- */
-struct xn_chain_data {
-		struct mbuf		*xn_tx_chain[NET_TX_RING_SIZE+1];
-		struct mbuf		*xn_rx_chain[NET_RX_RING_SIZE+1];
-};
-
-
-struct net_device_stats
-{
-	u_long	rx_packets;		/* total packets received	*/
-	u_long	tx_packets;		/* total packets transmitted	*/
-	u_long	rx_bytes;		/* total bytes received 	*/
-	u_long	tx_bytes;		/* total bytes transmitted	*/
-	u_long	rx_errors;		/* bad packets received		*/
-	u_long	tx_errors;		/* packet transmit problems	*/
-	u_long	rx_dropped;		/* no space in linux buffers	*/
-	u_long	tx_dropped;		/* no space available in linux	*/
-	u_long	multicast;		/* multicast packets received	*/
-	u_long	collisions;
-
-	/* detailed rx_errors: */
-	u_long	rx_length_errors;
-	u_long	rx_over_errors;		/* receiver ring buff overflow	*/
-	u_long	rx_crc_errors;		/* recved pkt with crc error	*/
-	u_long	rx_frame_errors;	/* recv'd frame alignment error */
-	u_long	rx_fifo_errors;		/* recv'r fifo overrun		*/
-	u_long	rx_missed_errors;	/* receiver missed packet	*/
-
-	/* detailed tx_errors */
-	u_long	tx_aborted_errors;
-	u_long	tx_carrier_errors;
-	u_long	tx_fifo_errors;
-	u_long	tx_heartbeat_errors;
-	u_long	tx_window_errors;
-	
-	/* for cslip etc */
-	u_long	rx_compressed;
-	u_long	tx_compressed;
-};
-
-struct netfront_info {
-		
-	struct ifnet *xn_ifp;
-
-	struct net_device_stats stats;
-	u_int tx_full;
-
-	netif_tx_front_ring_t tx;
-	netif_rx_front_ring_t rx;
-
-	struct mtx   tx_lock;
-	struct mtx   rx_lock;
-	struct sx    sc_lock;
-
-	u_int handle;
-	u_int irq;
-	u_int copying_receiver;
-	u_int carrier;
-		
-	/* Receive-ring batched refills. */
-#define RX_MIN_TARGET 32
-#define RX_MAX_TARGET NET_RX_RING_SIZE
-	int rx_min_target, rx_max_target, rx_target;
-
-	/*
-	 * {tx,rx}_skbs store outstanding skbuffs. The first entry in each
-	 * array is an index into a chain of free entries.
-	 */
-
-	grant_ref_t gref_tx_head;
-	grant_ref_t grant_tx_ref[NET_TX_RING_SIZE + 1]; 
-	grant_ref_t gref_rx_head;
-	grant_ref_t grant_rx_ref[NET_TX_RING_SIZE + 1]; 
-
-#define TX_MAX_TARGET min(NET_RX_RING_SIZE, 256)
-	struct xenbus_device *xbdev;
-	int tx_ring_ref;
-	int rx_ring_ref;
-	uint8_t mac[ETHER_ADDR_LEN];
-	struct xn_chain_data	xn_cdata;	/* mbufs */
-	struct mbuf_head xn_rx_batch;	/* head of the batch queue */
-
-	int			xn_if_flags;
-	struct callout	        xn_stat_ch;
-
-	u_long rx_pfn_array[NET_RX_RING_SIZE];
-	multicall_entry_t rx_mcl[NET_RX_RING_SIZE+1];
-	mmu_update_t rx_mmu[NET_RX_RING_SIZE];
-};
-
-#define rx_mbufs xn_cdata.xn_rx_chain
-#define tx_mbufs xn_cdata.xn_tx_chain
-
-#define XN_LOCK_INIT(_sc, _name) \
-        mtx_init(&(_sc)->tx_lock, #_name"_tx", "network transmit lock", MTX_DEF); \
-        mtx_init(&(_sc)->rx_lock, #_name"_rx", "network receive lock", MTX_DEF);  \
-        sx_init(&(_sc)->sc_lock, #_name"_rx")
-
-#define XN_RX_LOCK(_sc)           mtx_lock(&(_sc)->rx_lock)
-#define XN_RX_UNLOCK(_sc)         mtx_unlock(&(_sc)->rx_lock)
-
-#define XN_TX_LOCK(_sc)           mtx_lock(&(_sc)->tx_lock)
-#define XN_TX_UNLOCK(_sc)         mtx_unlock(&(_sc)->tx_lock)
-
-#define XN_LOCK(_sc)           sx_xlock(&(_sc)->sc_lock); 
-#define XN_UNLOCK(_sc)         sx_xunlock(&(_sc)->sc_lock); 
-
-#define XN_LOCK_ASSERT(_sc)    sx_assert(&(_sc)->sc_lock, SX_LOCKED); 
-#define XN_RX_LOCK_ASSERT(_sc)    mtx_assert(&(_sc)->rx_lock, MA_OWNED); 
-#define XN_TX_LOCK_ASSERT(_sc)    mtx_assert(&(_sc)->tx_lock, MA_OWNED); 
-#define XN_LOCK_DESTROY(_sc)   mtx_destroy(&(_sc)->rx_lock); \
-                               mtx_destroy(&(_sc)->tx_lock); \
-                               sx_destroy(&(_sc)->sc_lock);
-
-struct netfront_rx_info {
-	struct netif_rx_response rx;
-	struct netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
-};
-
-#define netfront_carrier_on(netif)	((netif)->carrier = 1)
-#define netfront_carrier_off(netif)	((netif)->carrier = 0)
-#define netfront_carrier_ok(netif)	((netif)->carrier)
-
-/* Access macros for acquiring freeing slots in xn_free_{tx,rx}_idxs[]. */
-
-
-
-/*
- * Access macros for acquiring freeing slots in tx_skbs[].
- */
-
-static inline void
-add_id_to_freelist(struct mbuf **list, unsigned short id)
-{
-	list[id] = list[0];
-	list[0]  = (void *)(u_long)id;
-}
-
-static inline unsigned short
-get_id_from_freelist(struct mbuf **list)
-{
-	u_int id = (u_int)(u_long)list[0];
-	list[0] = list[id];
-	return (id);
-}
-
-static inline int
-xennet_rxidx(RING_IDX idx)
-{
-	return idx & (NET_RX_RING_SIZE - 1);
-}
-
-static inline struct mbuf *
-xennet_get_rx_mbuf(struct netfront_info *np,
-						RING_IDX ri)
-{
-	int i = xennet_rxidx(ri);
-	struct mbuf *m;
-
-	m = np->rx_mbufs[i];
-	np->rx_mbufs[i] = NULL;
-	return (m);
-}
-
-static inline grant_ref_t
-xennet_get_rx_ref(struct netfront_info *np, RING_IDX ri)
-{
-	int i = xennet_rxidx(ri);
-	grant_ref_t ref = np->grant_rx_ref[i];
-	np->grant_rx_ref[i] = GRANT_INVALID_REF;
-	return ref;
-}
-
-#ifdef DEBUG
-
-#endif
-#define IPRINTK(fmt, args...) \
-    printf("[XEN] " fmt, ##args)
-#define WPRINTK(fmt, args...) \
-    printf("[XEN] " fmt, ##args)
-#define DPRINTK(fmt, args...) \
-    printf("[XEN] " fmt, ##args)
-
-
-static __inline struct mbuf* 
-makembuf (struct mbuf *buf)
-{
-	struct mbuf *m = NULL;
-	
-        MGETHDR (m, M_DONTWAIT, MT_DATA);
-	
-        if (! m)
-		return 0;
-		
-		M_MOVE_PKTHDR(m, buf);
-
-		m_cljget(m, M_DONTWAIT, MJUMPAGESIZE);
-        m->m_pkthdr.len = buf->m_pkthdr.len;
-        m->m_len = buf->m_len;
-		m_copydata(buf, 0, buf->m_pkthdr.len, mtod(m,caddr_t) );
-
-		m->m_ext.ext_args = (caddr_t *)(uintptr_t)(vtophys(mtod(m,caddr_t)) >> PAGE_SHIFT);
-	
-       	return m;
-}
-
-/**
- * Read the 'mac' node at the given device's node in the store, and parse that
- * as colon-separated octets, placing result the given mac array.  mac must be
- * a preallocated array of length ETH_ALEN (as declared in linux/if_ether.h).
- * Return 0 on success, or errno on error.
- */
-static int 
-xen_net_read_mac(struct xenbus_device *dev, uint8_t mac[])
-{
-	char *s;
-	int i;
-	char *e;
-	char *macstr = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
-	if (IS_ERR(macstr)) {
-		return PTR_ERR(macstr);
-	}
-	s = macstr;
-	for (i = 0; i < ETHER_ADDR_LEN; i++) {
-		mac[i] = strtoul(s, &e, 16);
-		if (s == e || (e[0] != ':' && e[0] != 0)) {
-			free(macstr, M_DEVBUF);
-			return ENOENT;
-		}
-		s = &e[1];
-	}
-	free(macstr, M_DEVBUF);
-	return 0;
-}
-
-/**
- * Entry point to this code when a new device is created.  Allocate the basic
- * structures and the ring buffers for communication with the backend, and
- * inform the backend of the appropriate details for those.  Switch to
- * Connected state.
- */
-static int 
-netfront_probe(struct xenbus_device *dev, const struct xenbus_device_id *id)
-{
-	int err;
-	struct ifnet *ifp;
-	struct netfront_info *info;
-
-	printf("netfront_probe() \n");
-	
-	err = create_netdev(dev, &ifp);
-	if (err) {
-		xenbus_dev_fatal(dev, err, "creating netdev");
-		return err;
-	}
-
-	info = ifp->if_softc;
-	dev->dev_driver_data = info;
-
-	return 0;
-}
-
-
-/**
- * We are reconnecting to the backend, due to a suspend/resume, or a backend
- * driver restart.  We tear down our netif structure and recreate it, but
- * leave the device-layer structures intact so that this is transparent to the
- * rest of the kernel.
- */
-static int 
-netfront_resume(struct xenbus_device *dev)
-{
-	struct netfront_info *info = dev->dev_driver_data;
-	
-	DPRINTK("%s\n", dev->nodename);
-	
-	netif_disconnect_backend(info);
-	return (0);
-}
-
-
-/* Common code used when first setting up, and when resuming. */
-static int 
-talk_to_backend(struct xenbus_device *dev, struct netfront_info *info)
-{
-	const char *message;
-	struct xenbus_transaction xbt;
-	int err;
-
-	err = xen_net_read_mac(dev, info->mac);
-	if (err) {
-		xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
-		goto out;
-	}
-
-	/* Create shared ring, alloc event channel. */
-	err = setup_device(dev, info);
-	if (err)
-		goto out;
-	
- again:
-	err = xenbus_transaction_start(&xbt);
-	if (err) {
-		xenbus_dev_fatal(dev, err, "starting transaction");
-		goto destroy_ring;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref","%u",
-			    info->tx_ring_ref);
-	if (err) {
-		message = "writing tx ring-ref";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref","%u",
-			    info->rx_ring_ref);
-	if (err) {
-		message = "writing rx ring-ref";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename,
-		"event-channel", "%u", irq_to_evtchn_port(info->irq));
-	if (err) {
-		message = "writing event-channel";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u",
-			    info->copying_receiver);
-	if (err) {
-		message = "writing request-rx-copy";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1);
-	if (err) {
-		message = "writing feature-rx-notify";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "feature-no-csum-offload", "%d", 1);
-	if (err) {
-		message = "writing feature-no-csum-offload";
-		goto abort_transaction;
-	}
-	err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", 1);
-	if (err) {
-		message = "writing feature-sg";
-		goto abort_transaction;
-	}
-#ifdef HAVE_TSO
-	err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", "%d", 1);
-	if (err) {
-		message = "writing feature-gso-tcpv4";
-		goto abort_transaction;
-	}
-#endif
-
-	err = xenbus_transaction_end(xbt, 0);
-	if (err) {
-		if (err == EAGAIN)
-			goto again;
-		xenbus_dev_fatal(dev, err, "completing transaction");
-		goto destroy_ring;
-	}
-	
-	return 0;
-	
- abort_transaction:
-	xenbus_transaction_end(xbt, 1);
-	xenbus_dev_fatal(dev, err, "%s", message);
- destroy_ring:
-	netif_free(info);
- out:
-	return err;
-}
-
-
-static int 
-setup_device(struct xenbus_device *dev, struct netfront_info *info)
-{
-	netif_tx_sring_t *txs;
-	netif_rx_sring_t *rxs;
-	int err;
-	struct ifnet *ifp;
-	
-	ifp = info->xn_ifp;
-
-	info->tx_ring_ref = GRANT_INVALID_REF;
-	info->rx_ring_ref = GRANT_INVALID_REF;
-	info->rx.sring = NULL;
-	info->tx.sring = NULL;
-	info->irq = 0;
-
-	txs = (netif_tx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT|M_ZERO);
-	if (!txs) {
-		err = ENOMEM;
-		xenbus_dev_fatal(dev, err, "allocating tx ring page");
-		goto fail;
-	}
-	SHARED_RING_INIT(txs);
-	FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE);
-	err = xenbus_grant_ring(dev, virt_to_mfn(txs));
-	if (err < 0)
-		goto fail;
-	info->tx_ring_ref = err;
-
-	rxs = (netif_rx_sring_t *)malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT|M_ZERO);
-	if (!rxs) {
-		err = ENOMEM;
-		xenbus_dev_fatal(dev, err, "allocating rx ring page");
-		goto fail;
-	}
-	SHARED_RING_INIT(rxs);
-	FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE);
-
-	err = xenbus_grant_ring(dev, virt_to_mfn(rxs));
-	if (err < 0)
-		goto fail;
-	info->rx_ring_ref = err;
-
-#if 0	
-	network_connect(ifp);
-#endif
-	err = bind_listening_port_to_irqhandler(dev->otherend_id,
-		"xn", xn_intr, info, INTR_TYPE_NET | INTR_MPSAFE, NULL);
-
-	if (err <= 0) {
-		xenbus_dev_fatal(dev, err,
-				 "bind_evtchn_to_irqhandler failed");
-		goto fail;
-	}
-	info->irq = err;
-	
-	show_device(info);
-	
-	return 0;
-	
- fail:
-	netif_free(info);
-	return err;
-}
-
-/**
- * Callback received when the backend's state changes.
- */
-static void
-backend_changed(struct xenbus_device *dev,
-			    XenbusState backend_state)
-{
-		struct netfront_info *sc = dev->dev_driver_data;
-		
-	DPRINTK("\n");
-	
-	switch (backend_state) {
-	case XenbusStateInitialising:
-	case XenbusStateInitialised:
-	case XenbusStateConnected:
-	case XenbusStateUnknown:
-	case XenbusStateClosed:
-	case XenbusStateReconfigured:
-	case XenbusStateReconfiguring:
-			break;
-	case XenbusStateInitWait:
-		if (dev->state != XenbusStateInitialising)
-			break;
-		if (network_connect(sc->xn_ifp) != 0)
-			break;
-		xenbus_switch_state(dev, XenbusStateConnected);
-#ifdef notyet		
-		(void)send_fake_arp(netdev);
-#endif		
-		break;	break;
-	case XenbusStateClosing:
-			xenbus_frontend_closed(dev);
-		break;
-	}
-}
-
-static void
-xn_free_rx_ring(struct netfront_info *sc)
-{
-#if 0
-	int i;
-	
-	for (i = 0; i < NET_RX_RING_SIZE; i++) {
-		if (sc->xn_cdata.xn_rx_chain[i] != NULL) {
-			m_freem(sc->xn_cdata.xn_rx_chain[i]);
-			sc->xn_cdata.xn_rx_chain[i] = NULL;
-		}
-	}
-	
-	sc->rx.rsp_cons = 0;
-	sc->xn_rx_if->req_prod = 0;
-	sc->xn_rx_if->event = sc->rx.rsp_cons ;
-#endif
-}
-
-static void
-xn_free_tx_ring(struct netfront_info *sc)
-{
-#if 0
-	int i;
-	
-	for (i = 0; i < NET_TX_RING_SIZE; i++) {
-		if (sc->xn_cdata.xn_tx_chain[i] != NULL) {
-			m_freem(sc->xn_cdata.xn_tx_chain[i]);
-			sc->xn_cdata.xn_tx_chain[i] = NULL;
-		}
-	}
-	
-	return;
-#endif
-}
-
-static inline int
-netfront_tx_slot_available(struct netfront_info *np)
-{
-	return ((np->tx.req_prod_pvt - np->tx.rsp_cons) <
-		(TX_MAX_TARGET - /* MAX_SKB_FRAGS */ 24 - 2));
-}
-static void
-netif_release_tx_bufs(struct netfront_info *np)
-{
-	struct mbuf *m;
-	int i;
-
-	for (i = 1; i <= NET_TX_RING_SIZE; i++) {
-		m = np->xn_cdata.xn_tx_chain[i];
-
-		if (((u_long)m) < KERNBASE)
-			continue;
-		gnttab_grant_foreign_access_ref(np->grant_tx_ref[i],
-		    np->xbdev->otherend_id, virt_to_mfn(mtod(m, vm_offset_t)),
-		    GNTMAP_readonly);
-		gnttab_release_grant_reference(&np->gref_tx_head,
-		    np->grant_tx_ref[i]);
-		np->grant_tx_ref[i] = GRANT_INVALID_REF;
-		add_id_to_freelist(np->tx_mbufs, i);
-		m_freem(m);
-	}
-}
-
-static void
-network_alloc_rx_buffers(struct netfront_info *sc)
-{
-	unsigned short id;
-	struct mbuf *m_new;
-	int i, batch_target, notify;
-	RING_IDX req_prod;
-	struct xen_memory_reservation reservation;
-	grant_ref_t ref;
-	int nr_flips;
-	netif_rx_request_t *req;
-	vm_offset_t vaddr;
-	u_long pfn;
-	
-	req_prod = sc->rx.req_prod_pvt;
-
-	if (unlikely(sc->carrier == 0))
-		return;
-	
-	/*
-	 * Allocate skbuffs greedily, even though we batch updates to the
-	 * receive ring. This creates a less bursty demand on the memory
-	 * allocator, so should reduce the chance of failed allocation
-	 * requests both for ourself and for other kernel subsystems.
-	 */
-	batch_target = sc->rx_target - (req_prod - sc->rx.rsp_cons);
-	for (i = mbufq_len(&sc->xn_rx_batch); i < batch_target; i++) {
-		MGETHDR(m_new, M_DONTWAIT, MT_DATA);
-		if (m_new == NULL) 
-			goto no_mbuf;
-
-		m_cljget(m_new, M_DONTWAIT, MJUMPAGESIZE);
-		if ((m_new->m_flags & M_EXT) == 0) {
-			m_freem(m_new);
-
-no_mbuf:
-			if (i != 0)
-				goto refill;
-			/*
-			 * XXX set timer
-			 */
-			break;
-		}
-		m_new->m_len = m_new->m_pkthdr.len = MJUMPAGESIZE;
-		
-		/* queue the mbufs allocated */
-		mbufq_tail(&sc->xn_rx_batch, m_new);
-	}
-	
-	/* Is the batch large enough to be worthwhile? */
-	if (i < (sc->rx_target/2)) {
-		if (req_prod >sc->rx.sring->req_prod)
-			goto push;
-		return;
-	}
-	/* Adjust floating fill target if we risked running out of buffers. */
-	if ( ((req_prod - sc->rx.sring->rsp_prod) < (sc->rx_target / 4)) &&
-	     ((sc->rx_target *= 2) > sc->rx_max_target) )
-		sc->rx_target = sc->rx_max_target;
-
-refill:
-	for (nr_flips = i = 0; ; i++) {
-		if ((m_new = mbufq_dequeue(&sc->xn_rx_batch)) == NULL)
-			break;
-
-		m_new->m_ext.ext_args = (vm_paddr_t *)(uintptr_t)(
-				vtophys(m_new->m_ext.ext_buf) >> PAGE_SHIFT);
-
-		id = xennet_rxidx(req_prod + i);
-
-		KASSERT(sc->xn_cdata.xn_rx_chain[id] == NULL,
-		    ("non-NULL xm_rx_chain"));
-		sc->xn_cdata.xn_rx_chain[id] = m_new;
-
-		ref = gnttab_claim_grant_reference(&sc->gref_rx_head);
-		KASSERT((short)ref >= 0, ("negative ref"));
-		sc->grant_rx_ref[id] = ref;
-
-		vaddr = mtod(m_new, vm_offset_t);
-		pfn = vtophys(vaddr) >> PAGE_SHIFT;
-		req = RING_GET_REQUEST(&sc->rx, req_prod + i);
-
-		if (sc->copying_receiver == 0) {
-			gnttab_grant_foreign_transfer_ref(ref,
-			    sc->xbdev->otherend_id, pfn);
-			sc->rx_pfn_array[nr_flips] = PFNTOMFN(pfn);
-			if (!xen_feature(XENFEAT_auto_translated_physmap)) {
-				/* Remove this page before passing
-				 * back to Xen.
-				 */
-				set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
-				MULTI_update_va_mapping(&sc->rx_mcl[i],
-				    vaddr, 0, 0);
-			}
-			nr_flips++;
-		} else {
-			gnttab_grant_foreign_access_ref(ref,
-			    sc->xbdev->otherend_id,
-			    PFNTOMFN(pfn), 0);
-		}
-		req->id = id;
-		req->gref = ref;
-		
-		sc->rx_pfn_array[i] =
-		    vtomach(mtod(m_new,vm_offset_t)) >> PAGE_SHIFT;
-	} 
-	
-	KASSERT(i, ("no mbufs processed")); /* should have returned earlier */
-	KASSERT(mbufq_len(&sc->xn_rx_batch) == 0, ("not all mbufs processed"));
-	/*
-	 * We may have allocated buffers which have entries outstanding
-	 * in the page * update queue -- make sure we flush those first!
-	 */
-	PT_UPDATES_FLUSH();
-	if (nr_flips != 0) {
-#ifdef notyet
-		/* Tell the ballon driver what is going on. */
-		balloon_update_driver_allowance(i);
-#endif
-		set_xen_guest_handle(reservation.extent_start, sc->rx_pfn_array);
-		reservation.nr_extents   = i;
-		reservation.extent_order = 0;
-		reservation.address_bits = 0;
-		reservation.domid        = DOMID_SELF;
-
-		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
-
-			/* After all PTEs have been zapped, flush the TLB. */
-			sc->rx_mcl[i-1].args[MULTI_UVMFLAGS_INDEX] =
-			    UVMF_TLB_FLUSH|UVMF_ALL;
-	
-			/* Give away a batch of pages. */
-			sc->rx_mcl[i].op = __HYPERVISOR_memory_op;
-			sc->rx_mcl[i].args[0] = XENMEM_decrease_reservation;
-			sc->rx_mcl[i].args[1] =  (u_long)&reservation;
-			/* Zap PTEs and give away pages in one big multicall. */
-			(void)HYPERVISOR_multicall(sc->rx_mcl, i+1);
-
-			/* Check return status of HYPERVISOR_dom_mem_op(). */
-			if (unlikely(sc->rx_mcl[i].result != i))
-				panic("Unable to reduce memory reservation\n");
-			} else {
-				if (HYPERVISOR_memory_op(
-				    XENMEM_decrease_reservation, &reservation)
-				    != i)
-					panic("Unable to reduce memory "
-					    "reservation\n");
-		}
-	} else {
-		wmb();
-	}
-			
-	/* Above is a suitable barrier to ensure backend will see requests. */
-	sc->rx.req_prod_pvt = req_prod + i;
-push:
-	RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&sc->rx, notify);
-	if (notify)
-		notify_remote_via_irq(sc->irq);
-}
-
-static void
-xn_rxeof(struct netfront_info *np)
-{
-	struct ifnet *ifp;
-	struct netfront_rx_info rinfo;
-	struct netif_rx_response *rx = &rinfo.rx;
-	struct netif_extra_info *extras = rinfo.extras;
-	RING_IDX i, rp;
-	multicall_entry_t *mcl;
-	struct mbuf *m;
-	struct mbuf_head rxq, errq;
-	int err, pages_flipped = 0;
-
-	XN_RX_LOCK_ASSERT(np);
-	if (!netfront_carrier_ok(np))
-		return;
-
-	mbufq_init(&errq);
-	mbufq_init(&rxq);
-
-	ifp = np->xn_ifp;
-	
-	rp = np->rx.sring->rsp_prod;
-	rmb();	/* Ensure we see queued responses up to 'rp'. */
-
-	i = np->rx.rsp_cons;
-	while ((i != rp)) {
-		memcpy(rx, RING_GET_RESPONSE(&np->rx, i), sizeof(*rx));
-		memset(extras, 0, sizeof(rinfo.extras));
-
-		m = NULL;
-		err = xennet_get_responses(np, &rinfo, rp, &m,
-		    &pages_flipped);
-
-		if (unlikely(err)) {
-				if (m)
-						mbufq_tail(&errq, m);
-			np->stats.rx_errors++;
-			i = np->rx.rsp_cons;
-			continue;
-		}
-
-		m->m_pkthdr.rcvif = ifp;
-		if ( rx->flags & NETRXF_data_validated ) {
-			/* Tell the stack the checksums are okay */
-			/*
-			 * XXX this isn't necessarily the case - need to add
-			 * check
-			 */
-				
-			m->m_pkthdr.csum_flags |=
-			    (CSUM_IP_CHECKED | CSUM_IP_VALID | CSUM_DATA_VALID
-			    | CSUM_PSEUDO_HDR);
-			m->m_pkthdr.csum_data = 0xffff;
-		}
-
-		np->stats.rx_packets++;
-		np->stats.rx_bytes += m->m_pkthdr.len;
-
-		mbufq_tail(&rxq, m);
-		np->rx.rsp_cons = ++i;
-	}
-
-	if (pages_flipped) {
-		/* Some pages are no longer absent... */
-#ifdef notyet
-		balloon_update_driver_allowance(-pages_flipped);
-#endif
-		/* Do all the remapping work, and M->P updates, in one big
-		 * hypercall.
-		 */
-		if (!!xen_feature(XENFEAT_auto_translated_physmap)) {
-			mcl = np->rx_mcl + pages_flipped;
-			mcl->op = __HYPERVISOR_mmu_update;
-			mcl->args[0] = (u_long)np->rx_mmu;
-			mcl->args[1] = pages_flipped;
-			mcl->args[2] = 0;
-			mcl->args[3] = DOMID_SELF;
-			(void)HYPERVISOR_multicall(np->rx_mcl,
-			    pages_flipped + 1);
-		}
-	}
-	
-	while ((m = mbufq_dequeue(&errq)))
-		m_freem(m);
-
-	/* 
-	 * Process all the mbufs after the remapping is complete.
-	 * Break the mbuf chain first though.
-	 */
-	while ((m = mbufq_dequeue(&rxq)) != NULL) {
-		ifp->if_ipackets++;
-			
-		/*
-		 * Do we really need to drop the rx lock?
-		 */
-		XN_RX_UNLOCK(np);
-		/* Pass it up. */
-		(*ifp->if_input)(ifp, m);
-		XN_RX_LOCK(np);
-	}
-	
-	np->rx.rsp_cons = i;
-
-#if 0
-	/* If we get a callback with very few responses, reduce fill target. */
-	/* NB. Note exponential increase, linear decrease. */
-	if (((np->rx.req_prod_pvt - np->rx.sring->rsp_prod) > 
-	    ((3*np->rx_target) / 4)) && (--np->rx_target < np->rx_min_target))
-		np->rx_target = np->rx_min_target;
-#endif
-	
-	network_alloc_rx_buffers(np);
-
-	np->rx.sring->rsp_event = i + 1;
-}
-
-static void 
-xn_txeof(struct netfront_info *np)
-{
-	RING_IDX i, prod;
-	unsigned short id;
-	struct ifnet *ifp;
-	struct mbuf *m;
-	
-	XN_TX_LOCK_ASSERT(np);
-	
-	if (!netfront_carrier_ok(np))
-		return;
-	
-	ifp = np->xn_ifp;
-	ifp->if_timer = 0;
-	
-	do {
-		prod = np->tx.sring->rsp_prod;
-		rmb(); /* Ensure we see responses up to 'rp'. */
-		
-		for (i = np->tx.rsp_cons; i != prod; i++) {
-			id = RING_GET_RESPONSE(&np->tx, i)->id;
-			m = np->xn_cdata.xn_tx_chain[id]; 
-			
-			ifp->if_opackets++;
-			KASSERT(m != NULL, ("mbuf not found in xn_tx_chain"));
-			M_ASSERTVALID(m);
-			if (unlikely(gnttab_query_foreign_access(
-			    np->grant_tx_ref[id]) != 0)) {
-				printf("network_tx_buf_gc: warning "
-				    "-- grant still in use by backend "
-				    "domain.\n");
-				goto out; 
-			}
-			gnttab_end_foreign_access_ref(
-				np->grant_tx_ref[id]);
-			gnttab_release_grant_reference(
-				&np->gref_tx_head, np->grant_tx_ref[id]);
-			np->grant_tx_ref[id] = GRANT_INVALID_REF;
-			
-			np->xn_cdata.xn_tx_chain[id] = NULL;
-			add_id_to_freelist(np->xn_cdata.xn_tx_chain, id);
-			m_freem(m);
-		}
-		np->tx.rsp_cons = prod;
-		
-		/*
-		 * Set a new event, then check for race with update of
-		 * tx_cons. Note that it is essential to schedule a
-		 * callback, no matter how few buffers are pending. Even if
-		 * there is space in the transmit ring, higher layers may
-		 * be blocked because too much data is outstanding: in such
-		 * cases notification from Xen is likely to be the only kick
-		 * that we'll get.
-		 */
-		np->tx.sring->rsp_event =
-		    prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
-
-		mb();
-		
-	} while (prod != np->tx.sring->rsp_prod);
-	
- out: 
-	if (np->tx_full &&
-	    ((np->tx.sring->req_prod - prod) < NET_TX_RING_SIZE)) {
-		np->tx_full = 0;
-#if 0
-		if (np->user_state == UST_OPEN)
-			netif_wake_queue(dev);
-#endif
-	}
-
-}
-
-static void
-xn_intr(void *xsc)
-{
-	struct netfront_info *np = xsc;
-	struct ifnet *ifp = np->xn_ifp;
-
-#if 0
-	if (!(np->rx.rsp_cons != np->rx.sring->rsp_prod &&
-	    likely(netfront_carrier_ok(np)) &&
-	    ifp->if_drv_flags & IFF_DRV_RUNNING))
-		return;
-#endif
-	if (np->tx.rsp_cons != np->tx.sring->rsp_prod) {
-		XN_TX_LOCK(np);
-		xn_txeof(np);
-		XN_TX_UNLOCK(np);			
-	}	
-
-	XN_RX_LOCK(np);
-	xn_rxeof(np);
-	XN_RX_UNLOCK(np);
-
-	if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
-	    !IFQ_DRV_IS_EMPTY(&ifp->if_snd))
-		xn_start(ifp);
-}
-
-
-static void
-xennet_move_rx_slot(struct netfront_info *np, struct mbuf *m,
-	grant_ref_t ref)
-{
-	int new = xennet_rxidx(np->rx.req_prod_pvt);
-
-	KASSERT(np->rx_mbufs[new] == NULL, ("rx_mbufs != NULL"));
-	np->rx_mbufs[new] = m;
-	np->grant_rx_ref[new] = ref;
-	RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->id = new;
-	RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->gref = ref;
-	np->rx.req_prod_pvt++;
-}
-
-static int
-xennet_get_extras(struct netfront_info *np,
-    struct netif_extra_info *extras, RING_IDX rp)
-{
-	struct netif_extra_info *extra;
-	RING_IDX cons = np->rx.rsp_cons;
-
-	int err = 0;
-
-	do {
-		struct mbuf *m;
-		grant_ref_t ref;
-
-		if (unlikely(cons + 1 == rp)) {
-#if 0			
-			if (net_ratelimit())
-				WPRINTK("Missing extra info\n");
-#endif			
-			err = -EINVAL;
-			break;
-		}
-
-		extra = (struct netif_extra_info *)
-		RING_GET_RESPONSE(&np->rx, ++cons);
-
-		if (unlikely(!extra->type ||
-			extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
-#if 0				
-			if (net_ratelimit())
-				WPRINTK("Invalid extra type: %d\n",
-					extra->type);
-#endif			
-			err = -EINVAL;
-		} else {
-			memcpy(&extras[extra->type - 1], extra, sizeof(*extra));
-		}
-
-		m = xennet_get_rx_mbuf(np, cons);
-		ref = xennet_get_rx_ref(np, cons);
-		xennet_move_rx_slot(np, m, ref);
-	} while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
-
-	np->rx.rsp_cons = cons;
-	return err;
-}
-
-static int
-xennet_get_responses(struct netfront_info *np,
-	struct netfront_rx_info *rinfo, RING_IDX rp,
-	struct mbuf  **list,
-	int *pages_flipped_p)
-{
-	int pages_flipped = *pages_flipped_p;
-	struct mmu_update *mmu;
-	struct multicall_entry *mcl;
-	struct netif_rx_response *rx = &rinfo->rx;
-	struct netif_extra_info *extras = rinfo->extras;
-	RING_IDX cons = np->rx.rsp_cons;
-	struct mbuf *m, *m0, *m_prev;
-	grant_ref_t ref = xennet_get_rx_ref(np, cons);
-	int max = 5 /* MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD) */;
-	int frags = 1;
-	int err = 0;
-	u_long ret;
-
-	m0 = m = m_prev = xennet_get_rx_mbuf(np, cons);
-
-	
-	if (rx->flags & NETRXF_extra_info) {
-		err = xennet_get_extras(np, extras, rp);
-		cons = np->rx.rsp_cons;
-	}
-
-
-	if (m0 != NULL) {
-			m0->m_pkthdr.len = 0;
-			m0->m_next = NULL;
-	}
-	
-	for (;;) {
-		u_long mfn;
-
-#if 0		
-		printf("rx->status=%hd rx->offset=%hu frags=%u\n",
-			rx->status, rx->offset, frags);
-#endif
-		if (unlikely(rx->status < 0 ||
-			rx->offset + rx->status > PAGE_SIZE)) {
-#if 0						
-			if (net_ratelimit())
-				WPRINTK("rx->offset: %x, size: %u\n",
-					rx->offset, rx->status);
-#endif						
-			xennet_move_rx_slot(np, m, ref);
-			err = -EINVAL;
-			goto next;
-		}
-		
-		/*
-		 * This definitely indicates a bug, either in this driver or in
-		 * the backend driver. In future this should flag the bad
-		 * situation to the system controller to reboot the backed.
-		 */
-		if (ref == GRANT_INVALID_REF) {
-#if 0 				
-			if (net_ratelimit())
-				WPRINTK("Bad rx response id %d.\n", rx->id);
-#endif			
-			err = -EINVAL;
-			goto next;
-		}
-
-		if (!np->copying_receiver) {
-			/* Memory pressure, insufficient buffer
-			 * headroom, ...
-			 */
-			if (!(mfn = gnttab_end_foreign_transfer_ref(ref))) {
-				if (net_ratelimit())
-					WPRINTK("Unfulfilled rx req "
-						"(id=%d, st=%d).\n",
-						rx->id, rx->status);
-				xennet_move_rx_slot(np, m, ref);
-				err = -ENOMEM;
-				goto next;
-			}
-
-			if (!xen_feature( XENFEAT_auto_translated_physmap)) {
-				/* Remap the page. */
-				void *vaddr = mtod(m, void *);
-				uint32_t pfn;
-
-				mcl = np->rx_mcl + pages_flipped;
-				mmu = np->rx_mmu + pages_flipped;
-
-				MULTI_update_va_mapping(mcl, (u_long)vaddr,
-				    (((vm_paddr_t)mfn) << PAGE_SHIFT) | PG_RW |
-				    PG_V | PG_M | PG_A, 0);
-				pfn = (uint32_t)m->m_ext.ext_args;
-				mmu->ptr = ((vm_paddr_t)mfn << PAGE_SHIFT) |
-				    MMU_MACHPHYS_UPDATE;
-				mmu->val = pfn;
-
-				set_phys_to_machine(pfn, mfn);
-			}
-			pages_flipped++;
-		} else {
-			ret = gnttab_end_foreign_access_ref(ref);
-			KASSERT(ret, ("ret != 0"));
-		}
-
-		gnttab_release_grant_reference(&np->gref_rx_head, ref);
-
-next:
-		if (m != NULL) {
-				m->m_len = rx->status;
-				m->m_data += rx->offset;
-				m0->m_pkthdr.len += rx->status;
-		}
-		
-		if (!(rx->flags & NETRXF_more_data))
-			break;
-
-		if (cons + frags == rp) {
-			if (net_ratelimit())
-				WPRINTK("Need more frags\n");
-			err = -ENOENT;
-				break;
-		}
-		m_prev = m;
-		
-		rx = RING_GET_RESPONSE(&np->rx, cons + frags);
-		m = xennet_get_rx_mbuf(np, cons + frags);
-
-		m_prev->m_next = m;
-		m->m_next = NULL;
-		ref = xennet_get_rx_ref(np, cons + frags);
-		frags++;
-	}
-	*list = m0;
-
-	if (unlikely(frags > max)) {
-		if (net_ratelimit())
-			WPRINTK("Too many frags\n");
-		err = -E2BIG;
-	}
-
-	if (unlikely(err))
-		np->rx.rsp_cons = cons + frags;
-
-	*pages_flipped_p = pages_flipped;
-
-	return err;
-}
-
-static void
-xn_tick_locked(struct netfront_info *sc) 
-{
-	XN_RX_LOCK_ASSERT(sc);
-	callout_reset(&sc->xn_stat_ch, hz, xn_tick, sc);
-
-	/* XXX placeholder for printing debug information */
-     
-}
-
-
-static void
-xn_tick(void *xsc) 
-{
-	struct netfront_info *sc;
-    
-	sc = xsc;
-	XN_RX_LOCK(sc);
-	xn_tick_locked(sc);
-	XN_RX_UNLOCK(sc);
-     
-}
-static void
-xn_start_locked(struct ifnet *ifp) 
-{
-	unsigned short id;
-	struct mbuf *m_head, *new_m;
-	struct netfront_info *sc;
-	netif_tx_request_t *tx;
-	RING_IDX i;
-	grant_ref_t ref;
-	u_long mfn, tx_bytes;
-	int notify;
-
-	sc = ifp->if_softc;
-	tx_bytes = 0;
-
-	if (!netfront_carrier_ok(sc))
-		return;
-	
-	for (i = sc->tx.req_prod_pvt; TRUE; i++) {
-		IF_DEQUEUE(&ifp->if_snd, m_head);
-		if (m_head == NULL) 
-			break;
-		
-		if (!netfront_tx_slot_available(sc)) {
-			IF_PREPEND(&ifp->if_snd, m_head);
-			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
-			break;
-		}
-		
-		id = get_id_from_freelist(sc->xn_cdata.xn_tx_chain);
-
-		/*
-		 * Start packing the mbufs in this chain into
-		 * the fragment pointers. Stop when we run out
-		 * of fragments or hit the end of the mbuf chain.
-		 */
-		new_m = makembuf(m_head);
-		tx = RING_GET_REQUEST(&sc->tx, i);
-		tx->id = id;
-		ref = gnttab_claim_grant_reference(&sc->gref_tx_head);
-		KASSERT((short)ref >= 0, ("Negative ref"));
-		mfn = virt_to_mfn(mtod(new_m, vm_offset_t));
-		gnttab_grant_foreign_access_ref(ref, sc->xbdev->otherend_id,
-		    mfn, GNTMAP_readonly);
-		tx->gref = sc->grant_tx_ref[id] = ref;
-		tx->size = new_m->m_pkthdr.len;
-#if 0
-		tx->flags = (skb->ip_summed == CHECKSUM_HW) ? NETTXF_csum_blank : 0;
-#endif
-		tx->flags = 0;
-		new_m->m_next = NULL;
-		new_m->m_nextpkt = NULL;
-
-		m_freem(m_head);
-
-		sc->xn_cdata.xn_tx_chain[id] = new_m;
-		BPF_MTAP(ifp, new_m);
-
-		sc->stats.tx_bytes += new_m->m_pkthdr.len;
-		sc->stats.tx_packets++;
-	}
-
-	sc->tx.req_prod_pvt = i;
-	RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&sc->tx, notify);
-	if (notify)
-		notify_remote_via_irq(sc->irq);
-
-	xn_txeof(sc);
-
-	if (RING_FULL(&sc->tx)) {
-		sc->tx_full = 1;
-#if 0
-		netif_stop_queue(dev);
-#endif
-	}
-
-	return;
-}    
-
-static void
-xn_start(struct ifnet *ifp)
-{
-	struct netfront_info *sc;
-	sc = ifp->if_softc;
-	XN_TX_LOCK(sc);
-	xn_start_locked(ifp);
-	XN_TX_UNLOCK(sc);
-}
-
-/* equivalent of network_open() in Linux */
-static void 
-xn_ifinit_locked(struct netfront_info *sc) 
-{
-	struct ifnet *ifp;
-	
-	XN_LOCK_ASSERT(sc);
-	
-	ifp = sc->xn_ifp;
-	
-	if (ifp->if_drv_flags & IFF_DRV_RUNNING) 
-		return;
-	
-	xn_stop(sc);
-	
-	network_alloc_rx_buffers(sc);
-	sc->rx.sring->rsp_event = sc->rx.rsp_cons + 1;
-	
-	ifp->if_drv_flags |= IFF_DRV_RUNNING;
-	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
-	
-	callout_reset(&sc->xn_stat_ch, hz, xn_tick, sc);
-
-}
-
-
-static void 
-xn_ifinit(void *xsc)
-{
-	struct netfront_info *sc = xsc;
-    
-	XN_LOCK(sc);
-	xn_ifinit_locked(sc);
-	XN_UNLOCK(sc);
-
-}
-
-
-static int
-xn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
-{
-	struct netfront_info *sc = ifp->if_softc;
-	struct ifreq *ifr = (struct ifreq *) data;
-	struct ifaddr *ifa = (struct ifaddr *)data;
-
-	int mask, error = 0;
-	switch(cmd) {
-	case SIOCSIFADDR:
-	case SIOCGIFADDR:
-		XN_LOCK(sc);
-		if (ifa->ifa_addr->sa_family == AF_INET) {
-			ifp->if_flags |= IFF_UP;
-			if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) 
-				xn_ifinit_locked(sc);
-			arp_ifinit(ifp, ifa);
-		} else
-			error = ether_ioctl(ifp, cmd, data);
-		XN_UNLOCK(sc);
-		break;
-	case SIOCSIFMTU:
-		/* XXX can we alter the MTU on a VN ?*/
-#ifdef notyet
-		if (ifr->ifr_mtu > XN_JUMBO_MTU)
-			error = EINVAL;
-		else 
-#endif
-		{
-			ifp->if_mtu = ifr->ifr_mtu;
-			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
-			xn_ifinit(sc);
-		}
-		break;
-	case SIOCSIFFLAGS:
-		XN_LOCK(sc);
-		if (ifp->if_flags & IFF_UP) {
-			/*
-			 * If only the state of the PROMISC flag changed,
-			 * then just use the 'set promisc mode' command
-			 * instead of reinitializing the entire NIC. Doing
-			 * a full re-init means reloading the firmware and
-			 * waiting for it to start up, which may take a
-			 * second or two.
-			 */
-#ifdef notyet
-			/* No promiscuous mode with Xen */
-			if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
-			    ifp->if_flags & IFF_PROMISC &&
-			    !(sc->xn_if_flags & IFF_PROMISC)) {
-				XN_SETBIT(sc, XN_RX_MODE,
-					  XN_RXMODE_RX_PROMISC);
-			} else if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
-				   !(ifp->if_flags & IFF_PROMISC) &&
-				   sc->xn_if_flags & IFF_PROMISC) {
-				XN_CLRBIT(sc, XN_RX_MODE,
-					  XN_RXMODE_RX_PROMISC);
-			} else
-#endif
-				xn_ifinit_locked(sc);
-		} else {
-			if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
-				xn_stop(sc);
-			}
-		}
-		sc->xn_if_flags = ifp->if_flags;
-		XN_UNLOCK(sc);
-		error = 0;
-		break;
-	case SIOCSIFCAP:
-		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
-		if (mask & IFCAP_HWCSUM) {
-			if (IFCAP_HWCSUM & ifp->if_capenable)
-				ifp->if_capenable &= ~IFCAP_HWCSUM;
-			else
-				ifp->if_capenable |= IFCAP_HWCSUM;
-		}
-		error = 0;
-		break;
-	case SIOCADDMULTI:
-	case SIOCDELMULTI:
-#ifdef notyet
-		if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
-			XN_LOCK(sc);
-			xn_setmulti(sc);
-			XN_UNLOCK(sc);
-			error = 0;
-		}
-#endif
-		/* FALLTHROUGH */
-	case SIOCSIFMEDIA:
-	case SIOCGIFMEDIA:
-		error = EINVAL;
-		break;
-	default:
-		error = ether_ioctl(ifp, cmd, data);
-	}
-    
-	return (error);
-}
-
-static void
-xn_stop(struct netfront_info *sc)
-{	
-	struct ifnet *ifp;
-
-	XN_LOCK_ASSERT(sc);
-    
-	ifp = sc->xn_ifp;
-
-	callout_stop(&sc->xn_stat_ch);
-
-	xn_free_rx_ring(sc);
-	xn_free_tx_ring(sc);
-    
-	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
-}
-
-/* START of Xenolinux helper functions adapted to FreeBSD */
-static int
-network_connect(struct ifnet *ifp)
-{
-	struct netfront_info *np;
-	int i, requeue_idx, err;
-	grant_ref_t ref;
-	netif_rx_request_t *req;
-	u_int feature_rx_copy, feature_rx_flip;
-
-	printf("network_connect\n");
-	
-	np = ifp->if_softc;
-	err = xenbus_scanf(XBT_NIL, np->xbdev->otherend,
-			   "feature-rx-copy", "%u", &feature_rx_copy);
-	if (err != 1)
-		feature_rx_copy = 0;
-	err = xenbus_scanf(XBT_NIL, np->xbdev->otherend,
-			   "feature-rx-flip", "%u", &feature_rx_flip);
-	if (err != 1)
-		feature_rx_flip = 1;
-
-	/*
-	 * Copy packets on receive path if:
-	 *  (a) This was requested by user, and the backend supports it; or
-	 *  (b) Flipping was requested, but this is unsupported by the backend.
-	 */
-	np->copying_receiver = ((MODPARM_rx_copy && feature_rx_copy) ||
-				(MODPARM_rx_flip && !feature_rx_flip));
-
-	XN_LOCK(np);
-	/* Recovery procedure: */
-	err = talk_to_backend(np->xbdev, np);
-	if (err) 
-			return (err);
-	
-	/* Step 1: Reinitialise variables. */
-	netif_release_tx_bufs(np);
-
-	/* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */
-	for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) {
-		struct mbuf *m;
-
-		if (np->rx_mbufs[i] == NULL)
-			continue;
-
-		m = np->rx_mbufs[requeue_idx] = xennet_get_rx_mbuf(np, i);
-		ref = np->grant_rx_ref[requeue_idx] = xennet_get_rx_ref(np, i);
-		req = RING_GET_REQUEST(&np->rx, requeue_idx);
-
-		if (!np->copying_receiver) {
-			gnttab_grant_foreign_transfer_ref(ref,
-			    np->xbdev->otherend_id,
-			    vtophys(mtod(m, vm_offset_t)));
-		} else {
-			gnttab_grant_foreign_access_ref(ref,
-			    np->xbdev->otherend_id,
-			    vtophys(mtod(m, vm_offset_t)), 0);
-		}
-		req->gref = ref;
-		req->id   = requeue_idx;
-
-		requeue_idx++;
-	}
-
-	np->rx.req_prod_pvt = requeue_idx;
-	
-	/* Step 3: All public and private state should now be sane.  Get
-	 * ready to start sending and receiving packets and give the driver
-	 * domain a kick because we've probably just requeued some
-	 * packets.
-	 */
-	netfront_carrier_on(np);
-	notify_remote_via_irq(np->irq);
-	XN_TX_LOCK(np);
-	xn_txeof(np);
-	XN_TX_UNLOCK(np);
-	network_alloc_rx_buffers(np);
-	XN_UNLOCK(np);
-
-	return (0);
-}
-
-
-static void 
-show_device(struct netfront_info *sc)
-{
-#ifdef DEBUG
-	if (sc) {
-		IPRINTK("<vif handle=%u %s(%s) evtchn=%u irq=%u tx=%p rx=%p>\n",
-			sc->xn_ifno,
-			be_state_name[sc->xn_backend_state],
-			sc->xn_user_state ? "open" : "closed",
-			sc->xn_evtchn,
-			sc->xn_irq,
-			sc->xn_tx_if,
-			sc->xn_rx_if);
-	} else {
-		IPRINTK("<vif NULL>\n");
-	}
-#endif
-}
-
-static int ifno = 0;
-
-/** Create a network device.
- * @param handle device handle
- */
-static int 
-create_netdev(struct xenbus_device *dev, struct ifnet **ifpp)
-{
-	int i;
-	struct netfront_info *np;
-	int err;
-	struct ifnet *ifp;
-
-	np = (struct netfront_info *)malloc(sizeof(struct netfront_info),
-	    M_DEVBUF, M_NOWAIT);
-	if (np == NULL)
-			return (ENOMEM);
-	
-	memset(np, 0, sizeof(struct netfront_info));
-	
-	np->xbdev         = dev;
-    
-	XN_LOCK_INIT(np, xennetif);
-	np->rx_target     = RX_MIN_TARGET;
-	np->rx_min_target = RX_MIN_TARGET;
-	np->rx_max_target = RX_MAX_TARGET;
-	
-	/* Initialise {tx,rx}_skbs to be a free chain containing every entry. */
-	for (i = 0; i <= NET_TX_RING_SIZE; i++) {
-		np->tx_mbufs[i] = (void *) ((u_long) i+1);
-		np->grant_tx_ref[i] = GRANT_INVALID_REF;	
-	}
-	for (i = 0; i <= NET_RX_RING_SIZE; i++) {
-		np->rx_mbufs[i] = NULL;
-		np->grant_rx_ref[i] = GRANT_INVALID_REF;
-	}
-	/* A grant for every tx ring slot */
-	if (gnttab_alloc_grant_references(TX_MAX_TARGET,
-					  &np->gref_tx_head) < 0) {
-		printf("#### netfront can't alloc tx grant refs\n");
-		err = ENOMEM;
-		goto exit;
-	}
-	/* A grant for every rx ring slot */
-	if (gnttab_alloc_grant_references(RX_MAX_TARGET,
-					  &np->gref_rx_head) < 0) {
-		printf("#### netfront can't alloc rx grant refs\n");
-		gnttab_free_grant_references(np->gref_tx_head);
-		err = ENOMEM;
-		goto exit;
-	}
-	
-	err = xen_net_read_mac(dev, np->mac);
-	if (err) {
-		xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
-		goto out;
-	}
-	
-	/* Set up ifnet structure */
-	*ifpp = ifp = np->xn_ifp = if_alloc(IFT_ETHER);
-    	ifp->if_softc = np;
-    	if_initname(ifp, "xn",  ifno++/* ifno */);
-    	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX;
-    	ifp->if_ioctl = xn_ioctl;
-    	ifp->if_output = ether_output;
-    	ifp->if_start = xn_start;
-#ifdef notyet
-    	ifp->if_watchdog = xn_watchdog;
-#endif
-    	ifp->if_init = xn_ifinit;
-    	ifp->if_mtu = ETHERMTU;
-    	ifp->if_snd.ifq_maxlen = NET_TX_RING_SIZE - 1;
-	
-#ifdef notyet
-    	ifp->if_hwassist = XN_CSUM_FEATURES;
-    	ifp->if_capabilities = IFCAP_HWCSUM;
-    	ifp->if_capenable = ifp->if_capabilities;
-#endif    
-	
-    	ether_ifattach(ifp, np->mac);
-    	callout_init(&np->xn_stat_ch, CALLOUT_MPSAFE);
-	netfront_carrier_off(np);
-
-	return (0);
-
-exit:
-	gnttab_free_grant_references(np->gref_tx_head);
-out:
-	panic("do something smart");
-
-}
-
-/**
- * Handle the change of state of the backend to Closing.  We must delete our
- * device-layer structures now, to ensure that writes are flushed through to
- * the backend.  Once is this done, we can switch to Closed in
- * acknowledgement.
- */
-#if 0
-static void netfront_closing(struct xenbus_device *dev)
-{
-#if 0
-	struct netfront_info *info = dev->dev_driver_data;
-
-	DPRINTK("netfront_closing: %s removed\n", dev->nodename);
-
-	close_netdev(info);
-#endif
-	xenbus_switch_state(dev, XenbusStateClosed);
-}
-#endif
-
-static int netfront_remove(struct xenbus_device *dev)
-{
-	struct netfront_info *info = dev->dev_driver_data;
-
-	DPRINTK("%s\n", dev->nodename);
-
-	netif_free(info);
-	free(info, M_DEVBUF);
-
-	return 0;
-}
-
-
-static void netif_free(struct netfront_info *info)
-{
-	netif_disconnect_backend(info);
-#if 0
-	close_netdev(info);
-#endif
-}
-
-
-
-static void netif_disconnect_backend(struct netfront_info *info)
-{
-	xn_stop(info);
-	end_access(info->tx_ring_ref, info->tx.sring);
-	end_access(info->rx_ring_ref, info->rx.sring);
-	info->tx_ring_ref = GRANT_INVALID_REF;
-	info->rx_ring_ref = GRANT_INVALID_REF;
-	info->tx.sring = NULL;
-	info->rx.sring = NULL;
-
-#if 0
-	if (info->irq)
-		unbind_from_irqhandler(info->irq, info->netdev);
-#else 
-	panic("FIX ME");
-#endif
-	info->irq = 0;
-}
-
-
-static void end_access(int ref, void *page)
-{
-	if (ref != GRANT_INVALID_REF)
-		gnttab_end_foreign_access(ref, page);
-}
-
-
-/* ** Driver registration ** */
-
-
-static struct xenbus_device_id netfront_ids[] = {
-	{ "vif" },
-	{ "" }
-};
-
-
-static struct xenbus_driver netfront = {
-	.name = "vif",
-	.ids = netfront_ids,
-	.probe = netfront_probe,
-	.remove = netfront_remove,
-	.resume = netfront_resume,
-	.otherend_changed = backend_changed,
-};
-
-static void
-netif_init(void *unused)
-{
-	if (!is_running_on_xen())
-		return;
-
-	if (is_initial_xendomain())
-		return;
-
-	IPRINTK("Initialising virtual ethernet driver.\n");
-
-	xenbus_register_frontend(&netfront);
-}
-
-SYSINIT(xennetif, SI_SUB_PSEUDO, SI_ORDER_SECOND, netif_init, NULL);
-
-
-/*
- * Local variables:
- * mode: C
- * c-set-style: "BSD"
- * c-basic-offset: 8
- * tab-width: 4
- * indent-tabs-mode: t
- * End:
- */