[deliverable/linux.git] / drivers / net / xen-netback / interface.c

/*
 * Network-device interface management.
 *
 * Copyright (c) 2004-2005, Keir Fraser
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation; or, when distributed
 * separately from the Linux kernel or incorporated into other
 * software packages, subject to the following license:
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this source file (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include "common.h"

#include <linux/kthread.h>
#include <linux/ethtool.h>
#include <linux/rtnetlink.h>
#include <linux/if_vlan.h>
#include <linux/vmalloc.h>

#include <xen/events.h>
#include <asm/xen/hypercall.h>

#define XENVIF_QUEUE_LENGTH 32
#define XENVIF_NAPI_WEIGHT  64

int xenvif_schedulable(struct xenvif *vif)
{
	return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
}

static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
{
	struct xenvif *vif = dev_id;

	if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
		napi_schedule(&vif->napi);

	return IRQ_HANDLED;
}

static int xenvif_poll(struct napi_struct *napi, int budget)
{
	struct xenvif *vif = container_of(napi, struct xenvif, napi);
	int work_done;

	work_done = xenvif_tx_action(vif, budget);

	if (work_done < budget) {
		int more_to_do = 0;
		unsigned long flags;

		/* It is necessary to disable IRQ before calling
		 * RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
		 * lose event from the frontend.
		 *
		 * Consider:
		 *   RING_HAS_UNCONSUMED_REQUESTS
		 *   <frontend generates event to trigger napi_schedule>
		 *   __napi_complete
		 *
		 * This handler is still in scheduled state so the
		 * event has no effect at all. After __napi_complete
		 * this handler is descheduled and cannot get
		 * scheduled again. We lose event in this case and the ring
		 * will be completely stalled.
		 */

		local_irq_save(flags);

		RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
		if (!more_to_do)
			__napi_complete(napi);

		local_irq_restore(flags);
	}

	return work_done;
}

static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
{
	struct xenvif *vif = dev_id;

	xenvif_kick_thread(vif);

	return IRQ_HANDLED;
}

static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
{
	xenvif_tx_interrupt(irq, dev_id);
	xenvif_rx_interrupt(irq, dev_id);

	return IRQ_HANDLED;
}

static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct xenvif *vif = netdev_priv(dev);
	int min_slots_needed;

	BUG_ON(skb->dev != dev);

	/* Drop the packet if vif is not ready */
	if (vif->task == NULL || !xenvif_schedulable(vif))
		goto drop;

	/* At best we'll need one slot for the header and one for each
	 * frag.
	 */
	min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;

	/* If the skb is GSO then we'll also need an extra slot for the
	 * metadata.
	 */
	if (skb_is_gso(skb))
		min_slots_needed++;

	/* If the skb can't possibly fit in the remaining slots
	 * then turn off the queue to give the ring a chance to
	 * drain.
	 */
	if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
		xenvif_stop_queue(vif);

	skb_queue_tail(&vif->rx_queue, skb);
	xenvif_kick_thread(vif);

	return NETDEV_TX_OK;

 drop:
	vif->dev->stats.tx_dropped++;
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
}

static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
{
	struct xenvif *vif = netdev_priv(dev);
	return &vif->dev->stats;
}

static void xenvif_up(struct xenvif *vif)
{
	napi_enable(&vif->napi);
	enable_irq(vif->tx_irq);
	if (vif->tx_irq != vif->rx_irq)
		enable_irq(vif->rx_irq);
	xenvif_check_rx_xenvif(vif);
}

static void xenvif_down(struct xenvif *vif)
{
	napi_disable(&vif->napi);
	disable_irq(vif->tx_irq);
	if (vif->tx_irq != vif->rx_irq)
		disable_irq(vif->rx_irq);
	del_timer_sync(&vif->credit_timeout);
}

static int xenvif_open(struct net_device *dev)
{
	struct xenvif *vif = netdev_priv(dev);
	if (netif_carrier_ok(dev))
		xenvif_up(vif);
	netif_start_queue(dev);
	return 0;
}

static int xenvif_close(struct net_device *dev)
{
	struct xenvif *vif = netdev_priv(dev);
	if (netif_carrier_ok(dev))
		xenvif_down(vif);
	netif_stop_queue(dev);
	return 0;
}

static int xenvif_change_mtu(struct net_device *dev, int mtu)
{
	struct xenvif *vif = netdev_priv(dev);
	int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;

	if (mtu > max)
		return -EINVAL;
	dev->mtu = mtu;
	return 0;
}

static netdev_features_t xenvif_fix_features(struct net_device *dev,
	netdev_features_t features)
{
	struct xenvif *vif = netdev_priv(dev);

	if (!vif->can_sg)
		features &= ~NETIF_F_SG;
	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
		features &= ~NETIF_F_TSO;
	if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
		features &= ~NETIF_F_TSO6;
	if (!vif->ip_csum)
		features &= ~NETIF_F_IP_CSUM;
	if (!vif->ipv6_csum)
		features &= ~NETIF_F_IPV6_CSUM;

	return features;
}

static const struct xenvif_stat {
	char name[ETH_GSTRING_LEN];
	u16 offset;
} xenvif_stats[] = {
	{
		"rx_gso_checksum_fixup",
		offsetof(struct xenvif, rx_gso_checksum_fixup)
	},
};

static int xenvif_get_sset_count(struct net_device *dev, int string_set)
{
	switch (string_set) {
	case ETH_SS_STATS:
		return ARRAY_SIZE(xenvif_stats);
	default:
		return -EINVAL;
	}
}

static void xenvif_get_ethtool_stats(struct net_device *dev,
				     struct ethtool_stats *stats, u64 * data)
{
	void *vif = netdev_priv(dev);
	int i;

	for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
		data[i] = *(unsigned long *)(vif + xenvif_stats[i].offset);
}

static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
{
	int i;

	switch (stringset) {
	case ETH_SS_STATS:
		for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
			memcpy(data + i * ETH_GSTRING_LEN,
			       xenvif_stats[i].name, ETH_GSTRING_LEN);
		break;
	}
}

static const struct ethtool_ops xenvif_ethtool_ops = {
	.get_link	= ethtool_op_get_link,

	.get_sset_count = xenvif_get_sset_count,
	.get_ethtool_stats = xenvif_get_ethtool_stats,
	.get_strings = xenvif_get_strings,
};

static const struct net_device_ops xenvif_netdev_ops = {
	.ndo_start_xmit	= xenvif_start_xmit,
	.ndo_get_stats	= xenvif_get_stats,
	.ndo_open	= xenvif_open,
	.ndo_stop	= xenvif_close,
	.ndo_change_mtu	= xenvif_change_mtu,
	.ndo_fix_features = xenvif_fix_features,
	.ndo_set_mac_address = eth_mac_addr,
	.ndo_validate_addr   = eth_validate_addr,
};

struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
			    unsigned int handle)
{
	int err;
	struct net_device *dev;
	struct xenvif *vif;
	char name[IFNAMSIZ] = {};
	int i;

	snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
	dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
	if (dev == NULL) {
		pr_warn("Could not allocate netdev for %s\n", name);
		return ERR_PTR(-ENOMEM);
	}

	SET_NETDEV_DEV(dev, parent);

	vif = netdev_priv(dev);

	vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
				     MAX_GRANT_COPY_OPS);
	if (vif->grant_copy_op == NULL) {
		pr_warn("Could not allocate grant copy space for %s\n", name);
		free_netdev(dev);
		return ERR_PTR(-ENOMEM);
	}

	vif->domid  = domid;
	vif->handle = handle;
	vif->can_sg = 1;
	vif->ip_csum = 1;
	vif->dev = dev;

	vif->credit_bytes = vif->remaining_credit = ~0UL;
	vif->credit_usec  = 0UL;
	init_timer(&vif->credit_timeout);
	vif->credit_window_start = get_jiffies_64();

	dev->netdev_ops	= &xenvif_netdev_ops;
	dev->hw_features = NETIF_F_SG |
		NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
		NETIF_F_TSO | NETIF_F_TSO6;
	dev->features = dev->hw_features | NETIF_F_RXCSUM;
	SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);

	dev->tx_queue_len = XENVIF_QUEUE_LENGTH;

	skb_queue_head_init(&vif->rx_queue);
	skb_queue_head_init(&vif->tx_queue);

	vif->pending_cons = 0;
	vif->pending_prod = MAX_PENDING_REQS;
	for (i = 0; i < MAX_PENDING_REQS; i++)
		vif->pending_ring[i] = i;
	for (i = 0; i < MAX_PENDING_REQS; i++)
		vif->mmap_pages[i] = NULL;

	/*
	 * Initialise a dummy MAC address. We choose the numerically
	 * largest non-broadcast address to prevent the address getting
	 * stolen by an Ethernet bridge for STP purposes.
	 * (FE:FF:FF:FF:FF:FF)
	 */
	memset(dev->dev_addr, 0xFF, ETH_ALEN);
	dev->dev_addr[0] &= ~0x01;

	netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);

	netif_carrier_off(dev);

	err = register_netdev(dev);
	if (err) {
		netdev_warn(dev, "Could not register device: err=%d\n", err);
		free_netdev(dev);
		return ERR_PTR(err);
	}

	netdev_dbg(dev, "Successfully created xenvif\n");

	__module_get(THIS_MODULE);

	return vif;
}

int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
		   unsigned long rx_ring_ref, unsigned int tx_evtchn,
		   unsigned int rx_evtchn)
{
	struct task_struct *task;
	int err = -ENOMEM;

	BUG_ON(vif->tx_irq);
	BUG_ON(vif->task);

	err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
	if (err < 0)
		goto err;

	init_waitqueue_head(&vif->wq);

	if (tx_evtchn == rx_evtchn) {
		/* feature-split-event-channels == 0 */
		err = bind_interdomain_evtchn_to_irqhandler(
			vif->domid, tx_evtchn, xenvif_interrupt, 0,
			vif->dev->name, vif);
		if (err < 0)
			goto err_unmap;
		vif->tx_irq = vif->rx_irq = err;
		disable_irq(vif->tx_irq);
	} else {
		/* feature-split-event-channels == 1 */
		snprintf(vif->tx_irq_name, sizeof(vif->tx_irq_name),
			 "%s-tx", vif->dev->name);
		err = bind_interdomain_evtchn_to_irqhandler(
			vif->domid, tx_evtchn, xenvif_tx_interrupt, 0,
			vif->tx_irq_name, vif);
		if (err < 0)
			goto err_unmap;
		vif->tx_irq = err;
		disable_irq(vif->tx_irq);

		snprintf(vif->rx_irq_name, sizeof(vif->rx_irq_name),
			 "%s-rx", vif->dev->name);
		err = bind_interdomain_evtchn_to_irqhandler(
			vif->domid, rx_evtchn, xenvif_rx_interrupt, 0,
			vif->rx_irq_name, vif);
		if (err < 0)
			goto err_tx_unbind;
		vif->rx_irq = err;
		disable_irq(vif->rx_irq);
	}

	task = kthread_create(xenvif_kthread,
			      (void *)vif, "%s", vif->dev->name);
	if (IS_ERR(task)) {
		pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
		err = PTR_ERR(task);
		goto err_rx_unbind;
	}

	vif->task = task;

	rtnl_lock();
	if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
		dev_set_mtu(vif->dev, ETH_DATA_LEN);
	netdev_update_features(vif->dev);
	netif_carrier_on(vif->dev);
	if (netif_running(vif->dev))
		xenvif_up(vif);
	rtnl_unlock();

	wake_up_process(vif->task);

	return 0;

err_rx_unbind:
	unbind_from_irqhandler(vif->rx_irq, vif);
	vif->rx_irq = 0;
err_tx_unbind:
	unbind_from_irqhandler(vif->tx_irq, vif);
	vif->tx_irq = 0;
err_unmap:
	xenvif_unmap_frontend_rings(vif);
err:
	module_put(THIS_MODULE);
	return err;
}

void xenvif_carrier_off(struct xenvif *vif)
{
	struct net_device *dev = vif->dev;

	rtnl_lock();
	netif_carrier_off(dev); /* discard queued packets */
	if (netif_running(dev))
		xenvif_down(vif);
	rtnl_unlock();
}

void xenvif_disconnect(struct xenvif *vif)
{
	if (netif_carrier_ok(vif->dev))
		xenvif_carrier_off(vif);

	if (vif->task) {
		kthread_stop(vif->task);
		vif->task = NULL;
	}

	if (vif->tx_irq) {
		if (vif->tx_irq == vif->rx_irq)
			unbind_from_irqhandler(vif->tx_irq, vif);
		else {
			unbind_from_irqhandler(vif->tx_irq, vif);
			unbind_from_irqhandler(vif->rx_irq, vif);
		}
		vif->tx_irq = 0;
	}

	xenvif_unmap_frontend_rings(vif);
}

void xenvif_free(struct xenvif *vif)
{
	netif_napi_del(&vif->napi);

	unregister_netdev(vif->dev);

	vfree(vif->grant_copy_op);
	free_netdev(vif->dev);

	module_put(THIS_MODULE);
}
Commit	Line	Data
f942dc25 IC	1	/*
	2	* Network-device interface management.
	3	*
	4	* Copyright (c) 2004-2005, Keir Fraser
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License version 2
	8	* as published by the Free Software Foundation; or, when distributed
	9	* separately from the Linux kernel or incorporated into other
	10	* software packages, subject to the following license:
	11	*
	12	* Permission is hereby granted, free of charge, to any person obtaining a copy
	13	* of this source file (the "Software"), to deal in the Software without
	14	* restriction, including without limitation the rights to use, copy, modify,
	15	* merge, publish, distribute, sublicense, and/or sell copies of the Software,
	16	* and to permit persons to whom the Software is furnished to do so, subject to
	17	* the following conditions:
	18	*
	19	* The above copyright notice and this permission notice shall be included in
	20	* all copies or substantial portions of the Software.
	21	*
	22	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	23	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	24	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	25	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	26	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	27	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	28	* IN THE SOFTWARE.
	29	*/
	30
	31	#include "common.h"
	32
b3f980bd	33	#include <linux/kthread.h>
f942dc25 IC	34	#include <linux/ethtool.h>
	35	#include <linux/rtnetlink.h>
	36	#include <linux/if_vlan.h>
f35f76ee	37	#include <linux/vmalloc.h>
f942dc25 IC	38
	39	#include <xen/events.h>
	40	#include <asm/xen/hypercall.h>
	41
	42	#define XENVIF_QUEUE_LENGTH 32
b3f980bd	43	#define XENVIF_NAPI_WEIGHT 64
f942dc25 IC	44
	45	int xenvif_schedulable(struct xenvif *vif)
	46	{
	47	return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
	48	}
	49
e1f00a69	50	static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
f942dc25 IC	51	{
	52	struct xenvif *vif = dev_id;
	53
b3f980bd WL	54	if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
b3f980bd WL	55	napi_schedule(&vif->napi);
f942dc25	56
e1f00a69 WL	57	return IRQ_HANDLED;
	58	}
	59
b3f980bd WL	60	static int xenvif_poll(struct napi_struct *napi, int budget)
	61	{
	62	struct xenvif *vif = container_of(napi, struct xenvif, napi);
	63	int work_done;
	64
7376419a	65	work_done = xenvif_tx_action(vif, budget);
b3f980bd WL	66
	67	if (work_done < budget) {
	68	int more_to_do = 0;
	69	unsigned long flags;
	70
	71	/* It is necessary to disable IRQ before calling
	72	* RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
	73	* lose event from the frontend.
	74	*
	75	* Consider:
	76	* RING_HAS_UNCONSUMED_REQUESTS
	77	* <frontend generates event to trigger napi_schedule>
	78	* __napi_complete
	79	*
	80	* This handler is still in scheduled state so the
	81	* event has no effect at all. After __napi_complete
	82	* this handler is descheduled and cannot get
	83	* scheduled again. We lose event in this case and the ring
	84	* will be completely stalled.
	85	*/
	86
	87	local_irq_save(flags);
	88
	89	RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
	90	if (!more_to_do)
	91	__napi_complete(napi);
	92
	93	local_irq_restore(flags);
	94	}
	95
	96	return work_done;
	97	}
	98
e1f00a69 WL	99	static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
	100	{
	101	struct xenvif *vif = dev_id;
	102
ca2f09f2	103	xenvif_kick_thread(vif);
f942dc25 IC	104
	105	return IRQ_HANDLED;
	106	}
	107
e1f00a69 WL	108	static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
	109	{
	110	xenvif_tx_interrupt(irq, dev_id);
	111	xenvif_rx_interrupt(irq, dev_id);
	112
	113	return IRQ_HANDLED;
	114	}
	115
f942dc25 IC	116	static int xenvif_start_xmit(struct sk_buff skb, struct net_device dev)
	117	{
	118	struct xenvif *vif = netdev_priv(dev);
ca2f09f2	119	int min_slots_needed;
f942dc25 IC	120
	121	BUG_ON(skb->dev != dev);
	122
b3f980bd	123	/* Drop the packet if vif is not ready */
ca2f09f2	124	if (vif->task == NULL \|\| !xenvif_schedulable(vif))
f942dc25 IC	125	goto drop;
f942dc25 IC	126
ca2f09f2 PD	127	/* At best we'll need one slot for the header and one for each
	128	* frag.
	129	*/
	130	min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;
f942dc25	131
ca2f09f2 PD	132	/* If the skb is GSO then we'll also need an extra slot for the
	133	* metadata.
	134	*/
836fbaf4	135	if (skb_is_gso(skb))
ca2f09f2	136	min_slots_needed++;
f942dc25	137
ca2f09f2 PD	138	/* If the skb can't possibly fit in the remaining slots
	139	* then turn off the queue to give the ring a chance to
	140	* drain.
	141	*/
	142	if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
	143	xenvif_stop_queue(vif);
f942dc25	144
ca2f09f2 PD	145	skb_queue_tail(&vif->rx_queue, skb);
ca2f09f2 PD	146	xenvif_kick_thread(vif);
f942dc25 IC	147
	148	return NETDEV_TX_OK;
	149
	150	drop:
	151	vif->dev->stats.tx_dropped++;
	152	dev_kfree_skb(skb);
	153	return NETDEV_TX_OK;
	154	}
	155
f942dc25 IC	156	static struct net_device_stats xenvif_get_stats(struct net_device dev)
	157	{
	158	struct xenvif *vif = netdev_priv(dev);
	159	return &vif->dev->stats;
	160	}
	161
	162	static void xenvif_up(struct xenvif *vif)
	163	{
b3f980bd	164	napi_enable(&vif->napi);
e1f00a69 WL	165	enable_irq(vif->tx_irq);
	166	if (vif->tx_irq != vif->rx_irq)
	167	enable_irq(vif->rx_irq);
7376419a	168	xenvif_check_rx_xenvif(vif);
f942dc25 IC	169	}
	170
	171	static void xenvif_down(struct xenvif *vif)
	172	{
b3f980bd	173	napi_disable(&vif->napi);
e1f00a69 WL	174	disable_irq(vif->tx_irq);
	175	if (vif->tx_irq != vif->rx_irq)
	176	disable_irq(vif->rx_irq);
3e55f8b3	177	del_timer_sync(&vif->credit_timeout);
f942dc25 IC	178	}
	179
	180	static int xenvif_open(struct net_device *dev)
	181	{
	182	struct xenvif *vif = netdev_priv(dev);
	183	if (netif_carrier_ok(dev))
	184	xenvif_up(vif);
	185	netif_start_queue(dev);
	186	return 0;
	187	}
	188
	189	static int xenvif_close(struct net_device *dev)
	190	{
	191	struct xenvif *vif = netdev_priv(dev);
	192	if (netif_carrier_ok(dev))
	193	xenvif_down(vif);
	194	netif_stop_queue(dev);
	195	return 0;
	196	}
	197
	198	static int xenvif_change_mtu(struct net_device *dev, int mtu)
	199	{
	200	struct xenvif *vif = netdev_priv(dev);
	201	int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
	202
	203	if (mtu > max)
	204	return -EINVAL;
	205	dev->mtu = mtu;
	206	return 0;
	207	}
	208
c8f44aff MM	209	static netdev_features_t xenvif_fix_features(struct net_device *dev,
c8f44aff MM	210	netdev_features_t features)
f942dc25 IC	211	{
f942dc25 IC	212	struct xenvif *vif = netdev_priv(dev);
f942dc25	213
47103041 MM	214	if (!vif->can_sg)
47103041 MM	215	features &= ~NETIF_F_SG;
82cada22	216	if (~(vif->gso_mask \| vif->gso_prefix_mask) & GSO_BIT(TCPV4))
47103041	217	features &= ~NETIF_F_TSO;
82cada22 PD	218	if (~(vif->gso_mask \| vif->gso_prefix_mask) & GSO_BIT(TCPV6))
82cada22 PD	219	features &= ~NETIF_F_TSO6;
146c8a77	220	if (!vif->ip_csum)
47103041	221	features &= ~NETIF_F_IP_CSUM;
146c8a77 PD	222	if (!vif->ipv6_csum)
146c8a77 PD	223	features &= ~NETIF_F_IPV6_CSUM;
f942dc25	224
47103041	225	return features;
f942dc25 IC	226	}
	227
	228	static const struct xenvif_stat {
	229	char name[ETH_GSTRING_LEN];
	230	u16 offset;
	231	} xenvif_stats[] = {
	232	{
	233	"rx_gso_checksum_fixup",
	234	offsetof(struct xenvif, rx_gso_checksum_fixup)
	235	},
	236	};
	237
	238	static int xenvif_get_sset_count(struct net_device *dev, int string_set)
	239	{
	240	switch (string_set) {
	241	case ETH_SS_STATS:
	242	return ARRAY_SIZE(xenvif_stats);
	243	default:
	244	return -EINVAL;
	245	}
	246	}
	247
	248	static void xenvif_get_ethtool_stats(struct net_device *dev,
	249	struct ethtool_stats stats, u64 data)
	250	{
	251	void *vif = netdev_priv(dev);
	252	int i;
	253
	254	for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
	255	data[i] = (unsigned long )(vif + xenvif_stats[i].offset);
	256	}
	257
	258	static void xenvif_get_strings(struct net_device dev, u32 stringset, u8 data)
	259	{
	260	int i;
	261
	262	switch (stringset) {
	263	case ETH_SS_STATS:
	264	for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
	265	memcpy(data + i * ETH_GSTRING_LEN,
	266	xenvif_stats[i].name, ETH_GSTRING_LEN);
	267	break;
	268	}
	269	}
	270
813abbba	271	static const struct ethtool_ops xenvif_ethtool_ops = {
f942dc25 IC	272	.get_link = ethtool_op_get_link,
	273
	274	.get_sset_count = xenvif_get_sset_count,
	275	.get_ethtool_stats = xenvif_get_ethtool_stats,
	276	.get_strings = xenvif_get_strings,
	277	};
	278
813abbba	279	static const struct net_device_ops xenvif_netdev_ops = {
f942dc25 IC	280	.ndo_start_xmit = xenvif_start_xmit,
	281	.ndo_get_stats = xenvif_get_stats,
	282	.ndo_open = xenvif_open,
	283	.ndo_stop = xenvif_close,
	284	.ndo_change_mtu = xenvif_change_mtu,
47103041	285	.ndo_fix_features = xenvif_fix_features,
4a633a60 MW	286	.ndo_set_mac_address = eth_mac_addr,
4a633a60 MW	287	.ndo_validate_addr = eth_validate_addr,
f942dc25 IC	288	};
	289
	290	struct xenvif xenvif_alloc(struct device parent, domid_t domid,
	291	unsigned int handle)
	292	{
	293	int err;
	294	struct net_device *dev;
	295	struct xenvif *vif;
	296	char name[IFNAMSIZ] = {};
b3f980bd	297	int i;
f942dc25 IC	298
	299	snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
	300	dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
	301	if (dev == NULL) {
b3f980bd	302	pr_warn("Could not allocate netdev for %s\n", name);
f942dc25 IC	303	return ERR_PTR(-ENOMEM);
	304	}
	305
	306	SET_NETDEV_DEV(dev, parent);
	307
	308	vif = netdev_priv(dev);
ac3d5ac2 PD	309
	310	vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
	311	MAX_GRANT_COPY_OPS);
	312	if (vif->grant_copy_op == NULL) {
	313	pr_warn("Could not allocate grant copy space for %s\n", name);
	314	free_netdev(dev);
	315	return ERR_PTR(-ENOMEM);
	316	}
	317
f942dc25 IC	318	vif->domid = domid;
f942dc25 IC	319	vif->handle = handle;
f942dc25	320	vif->can_sg = 1;
146c8a77	321	vif->ip_csum = 1;
f942dc25	322	vif->dev = dev;
f942dc25 IC	323
	324	vif->credit_bytes = vif->remaining_credit = ~0UL;
	325	vif->credit_usec = 0UL;
	326	init_timer(&vif->credit_timeout);
059dfa6a	327	vif->credit_window_start = get_jiffies_64();
f942dc25 IC	328
f942dc25 IC	329	dev->netdev_ops = &xenvif_netdev_ops;
146c8a77 PD	330	dev->hw_features = NETIF_F_SG \|
146c8a77 PD	331	NETIF_F_IP_CSUM \| NETIF_F_IPV6_CSUM \|
82cada22	332	NETIF_F_TSO \| NETIF_F_TSO6;
7365bcfa	333	dev->features = dev->hw_features \| NETIF_F_RXCSUM;
f942dc25 IC	334	SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
	335
	336	dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
	337
b3f980bd WL	338	skb_queue_head_init(&vif->rx_queue);
	339	skb_queue_head_init(&vif->tx_queue);
	340
	341	vif->pending_cons = 0;
	342	vif->pending_prod = MAX_PENDING_REQS;
	343	for (i = 0; i < MAX_PENDING_REQS; i++)
	344	vif->pending_ring[i] = i;
	345	for (i = 0; i < MAX_PENDING_REQS; i++)
	346	vif->mmap_pages[i] = NULL;
	347
f942dc25 IC	348	/*
	349	* Initialise a dummy MAC address. We choose the numerically
	350	* largest non-broadcast address to prevent the address getting
	351	* stolen by an Ethernet bridge for STP purposes.
	352	* (FE:FF:FF:FF:FF:FF)
	353	*/
	354	memset(dev->dev_addr, 0xFF, ETH_ALEN);
	355	dev->dev_addr[0] &= ~0x01;
	356
b3f980bd WL	357	netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);
b3f980bd WL	358
f942dc25 IC	359	netif_carrier_off(dev);
	360
	361	err = register_netdev(dev);
	362	if (err) {
	363	netdev_warn(dev, "Could not register device: err=%d\n", err);
	364	free_netdev(dev);
	365	return ERR_PTR(err);
	366	}
	367
	368	netdev_dbg(dev, "Successfully created xenvif\n");
279f438e PD	369
	370	__module_get(THIS_MODULE);
	371
f942dc25 IC	372	return vif;
	373	}
	374
	375	int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
e1f00a69 WL	376	unsigned long rx_ring_ref, unsigned int tx_evtchn,
e1f00a69 WL	377	unsigned int rx_evtchn)
f942dc25	378	{
67fa3660	379	struct task_struct *task;
f942dc25 IC	380	int err = -ENOMEM;
f942dc25 IC	381
67fa3660 PD	382	BUG_ON(vif->tx_irq);
67fa3660 PD	383	BUG_ON(vif->task);
f942dc25	384
7376419a	385	err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
f942dc25 IC	386	if (err < 0)
	387	goto err;
	388
ca2f09f2 PD	389	init_waitqueue_head(&vif->wq);
ca2f09f2 PD	390
e1f00a69 WL	391	if (tx_evtchn == rx_evtchn) {
	392	/* feature-split-event-channels == 0 */
	393	err = bind_interdomain_evtchn_to_irqhandler(
	394	vif->domid, tx_evtchn, xenvif_interrupt, 0,
	395	vif->dev->name, vif);
	396	if (err < 0)
	397	goto err_unmap;
	398	vif->tx_irq = vif->rx_irq = err;
	399	disable_irq(vif->tx_irq);
	400	} else {
	401	/* feature-split-event-channels == 1 */
	402	snprintf(vif->tx_irq_name, sizeof(vif->tx_irq_name),
	403	"%s-tx", vif->dev->name);
	404	err = bind_interdomain_evtchn_to_irqhandler(
	405	vif->domid, tx_evtchn, xenvif_tx_interrupt, 0,
	406	vif->tx_irq_name, vif);
	407	if (err < 0)
	408	goto err_unmap;
	409	vif->tx_irq = err;
	410	disable_irq(vif->tx_irq);
	411
	412	snprintf(vif->rx_irq_name, sizeof(vif->rx_irq_name),
	413	"%s-rx", vif->dev->name);
	414	err = bind_interdomain_evtchn_to_irqhandler(
	415	vif->domid, rx_evtchn, xenvif_rx_interrupt, 0,
	416	vif->rx_irq_name, vif);
	417	if (err < 0)
	418	goto err_tx_unbind;
	419	vif->rx_irq = err;
	420	disable_irq(vif->rx_irq);
	421	}
f942dc25	422
67fa3660 PD	423	task = kthread_create(xenvif_kthread,
	424	(void *)vif, "%s", vif->dev->name);
	425	if (IS_ERR(task)) {
b3f980bd	426	pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
67fa3660	427	err = PTR_ERR(task);
b3f980bd WL	428	goto err_rx_unbind;
b3f980bd WL	429	}
f942dc25	430
67fa3660 PD	431	vif->task = task;
67fa3660 PD	432
f942dc25	433	rtnl_lock();
47103041 MM	434	if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
	435	dev_set_mtu(vif->dev, ETH_DATA_LEN);
	436	netdev_update_features(vif->dev);
	437	netif_carrier_on(vif->dev);
d0e5d832 DV	438	if (netif_running(vif->dev))
d0e5d832 DV	439	xenvif_up(vif);
f942dc25 IC	440	rtnl_unlock();
f942dc25 IC	441
b3f980bd WL	442	wake_up_process(vif->task);
b3f980bd WL	443
f942dc25	444	return 0;
b3f980bd WL	445
	446	err_rx_unbind:
	447	unbind_from_irqhandler(vif->rx_irq, vif);
	448	vif->rx_irq = 0;
e1f00a69 WL	449	err_tx_unbind:
	450	unbind_from_irqhandler(vif->tx_irq, vif);
	451	vif->tx_irq = 0;
f942dc25	452	err_unmap:
7376419a	453	xenvif_unmap_frontend_rings(vif);
f942dc25	454	err:
b103f358	455	module_put(THIS_MODULE);
f942dc25 IC	456	return err;
	457	}
	458
48856286	459	void xenvif_carrier_off(struct xenvif *vif)
f942dc25 IC	460	{
f942dc25 IC	461	struct net_device *dev = vif->dev;
48856286 IC	462
	463	rtnl_lock();
	464	netif_carrier_off(dev); /* discard queued packets */
	465	if (netif_running(dev))
	466	xenvif_down(vif);
	467	rtnl_unlock();
48856286 IC	468	}
	469
	470	void xenvif_disconnect(struct xenvif *vif)
	471	{
	472	if (netif_carrier_ok(vif->dev))
	473	xenvif_carrier_off(vif);
f942dc25	474
67fa3660	475	if (vif->task) {
db739ef3	476	kthread_stop(vif->task);
67fa3660 PD	477	vif->task = NULL;
67fa3660 PD	478	}
db739ef3	479
e1f00a69 WL	480	if (vif->tx_irq) {
	481	if (vif->tx_irq == vif->rx_irq)
	482	unbind_from_irqhandler(vif->tx_irq, vif);
	483	else {
	484	unbind_from_irqhandler(vif->tx_irq, vif);
	485	unbind_from_irqhandler(vif->rx_irq, vif);
	486	}
279f438e	487	vif->tx_irq = 0;
b103f358	488	}
f942dc25	489
279f438e PD	490	xenvif_unmap_frontend_rings(vif);
	491	}
	492
	493	void xenvif_free(struct xenvif *vif)
	494	{
b3f980bd WL	495	netif_napi_del(&vif->napi);
b3f980bd WL	496
f942dc25 IC	497	unregister_netdev(vif->dev);
f942dc25 IC	498
ac3d5ac2	499	vfree(vif->grant_copy_op);
f942dc25	500	free_netdev(vif->dev);
b103f358	501
279f438e	502	module_put(THIS_MODULE);
f942dc25	503	}