[linux-2.6-block.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 int xenvif_rx_schedulable(struct xenvif *vif)
{
	return xenvif_schedulable(vif) && !xenvif_rx_ring_full(vif);
}

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

	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;

	if (xenvif_rx_schedulable(vif))
		netif_wake_queue(vif->dev);

	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);

	BUG_ON(skb->dev != dev);

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

	/* Drop the packet if the target domain has no receive buffers. */
	if (!xenvif_rx_schedulable(vif))
		goto drop;

	/* Reserve ring slots for the worst-case number of fragments. */
	vif->rx_req_cons_peek += xenvif_count_skb_slots(vif, skb);

	if (vif->can_queue && xenvif_must_stop_queue(vif))
		netif_stop_queue(dev);

	xenvif_queue_tx_skb(vif, skb);

	return NETDEV_TX_OK;

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

void xenvif_notify_tx_completion(struct xenvif *vif)
{
	if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
		netif_wake_queue(vif->dev);
}

static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
{
	struct xenvif *vif = netdev_priv(dev);
	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;

	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);
	}

	init_waitqueue_head(&vif->wq);
	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
	50	static int xenvif_rx_schedulable(struct xenvif *vif)
	51	{
7376419a	52	return xenvif_schedulable(vif) && !xenvif_rx_ring_full(vif);
f942dc25 IC	53	}
f942dc25 IC	54
e1f00a69	55	static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
f942dc25 IC	56	{
	57	struct xenvif *vif = dev_id;
	58
b3f980bd WL	59	if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
b3f980bd WL	60	napi_schedule(&vif->napi);
f942dc25	61
e1f00a69 WL	62	return IRQ_HANDLED;
	63	}
	64
b3f980bd WL	65	static int xenvif_poll(struct napi_struct *napi, int budget)
	66	{
	67	struct xenvif *vif = container_of(napi, struct xenvif, napi);
	68	int work_done;
	69
7376419a	70	work_done = xenvif_tx_action(vif, budget);
b3f980bd WL	71
	72	if (work_done < budget) {
	73	int more_to_do = 0;
	74	unsigned long flags;
	75
	76	/* It is necessary to disable IRQ before calling
	77	* RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
	78	* lose event from the frontend.
	79	*
	80	* Consider:
	81	* RING_HAS_UNCONSUMED_REQUESTS
	82	* <frontend generates event to trigger napi_schedule>
	83	* __napi_complete
	84	*
	85	* This handler is still in scheduled state so the
	86	* event has no effect at all. After __napi_complete
	87	* this handler is descheduled and cannot get
	88	* scheduled again. We lose event in this case and the ring
	89	* will be completely stalled.
	90	*/
	91
	92	local_irq_save(flags);
	93
	94	RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
	95	if (!more_to_do)
	96	__napi_complete(napi);
	97
	98	local_irq_restore(flags);
	99	}
	100
	101	return work_done;
	102	}
	103
e1f00a69 WL	104	static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
	105	{
	106	struct xenvif *vif = dev_id;
	107
f942dc25 IC	108	if (xenvif_rx_schedulable(vif))
	109	netif_wake_queue(vif->dev);
	110
	111	return IRQ_HANDLED;
	112	}
	113
e1f00a69 WL	114	static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
	115	{
	116	xenvif_tx_interrupt(irq, dev_id);
	117	xenvif_rx_interrupt(irq, dev_id);
	118
	119	return IRQ_HANDLED;
	120	}
	121
f942dc25 IC	122	static int xenvif_start_xmit(struct sk_buff skb, struct net_device dev)
	123	{
	124	struct xenvif *vif = netdev_priv(dev);
	125
	126	BUG_ON(skb->dev != dev);
	127
b3f980bd WL	128	/* Drop the packet if vif is not ready */
b3f980bd WL	129	if (vif->task == NULL)
f942dc25 IC	130	goto drop;
	131
	132	/* Drop the packet if the target domain has no receive buffers. */
	133	if (!xenvif_rx_schedulable(vif))
	134	goto drop;
	135
	136	/* Reserve ring slots for the worst-case number of fragments. */
7376419a	137	vif->rx_req_cons_peek += xenvif_count_skb_slots(vif, skb);
f942dc25	138
7376419a	139	if (vif->can_queue && xenvif_must_stop_queue(vif))
f942dc25 IC	140	netif_stop_queue(dev);
f942dc25 IC	141
7376419a	142	xenvif_queue_tx_skb(vif, skb);
f942dc25 IC	143
	144	return NETDEV_TX_OK;
	145
	146	drop:
	147	vif->dev->stats.tx_dropped++;
	148	dev_kfree_skb(skb);
	149	return NETDEV_TX_OK;
	150	}
	151
f942dc25 IC	152	void xenvif_notify_tx_completion(struct xenvif *vif)
	153	{
	154	if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
	155	netif_wake_queue(vif->dev);
	156	}
	157
	158	static struct net_device_stats xenvif_get_stats(struct net_device dev)
	159	{
	160	struct xenvif *vif = netdev_priv(dev);
	161	return &vif->dev->stats;
	162	}
	163
	164	static void xenvif_up(struct xenvif *vif)
	165	{
b3f980bd	166	napi_enable(&vif->napi);
e1f00a69 WL	167	enable_irq(vif->tx_irq);
	168	if (vif->tx_irq != vif->rx_irq)
	169	enable_irq(vif->rx_irq);
7376419a	170	xenvif_check_rx_xenvif(vif);
f942dc25 IC	171	}
	172
	173	static void xenvif_down(struct xenvif *vif)
	174	{
b3f980bd	175	napi_disable(&vif->napi);
e1f00a69 WL	176	disable_irq(vif->tx_irq);
	177	if (vif->tx_irq != vif->rx_irq)
	178	disable_irq(vif->rx_irq);
3e55f8b3	179	del_timer_sync(&vif->credit_timeout);
f942dc25 IC	180	}
	181
	182	static int xenvif_open(struct net_device *dev)
	183	{
	184	struct xenvif *vif = netdev_priv(dev);
	185	if (netif_carrier_ok(dev))
	186	xenvif_up(vif);
	187	netif_start_queue(dev);
	188	return 0;
	189	}
	190
	191	static int xenvif_close(struct net_device *dev)
	192	{
	193	struct xenvif *vif = netdev_priv(dev);
	194	if (netif_carrier_ok(dev))
	195	xenvif_down(vif);
	196	netif_stop_queue(dev);
	197	return 0;
	198	}
	199
	200	static int xenvif_change_mtu(struct net_device *dev, int mtu)
	201	{
	202	struct xenvif *vif = netdev_priv(dev);
	203	int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
	204
	205	if (mtu > max)
	206	return -EINVAL;
	207	dev->mtu = mtu;
	208	return 0;
	209	}
	210
c8f44aff MM	211	static netdev_features_t xenvif_fix_features(struct net_device *dev,
c8f44aff MM	212	netdev_features_t features)
f942dc25 IC	213	{
f942dc25 IC	214	struct xenvif *vif = netdev_priv(dev);
f942dc25	215
47103041 MM	216	if (!vif->can_sg)
47103041 MM	217	features &= ~NETIF_F_SG;
82cada22	218	if (~(vif->gso_mask \| vif->gso_prefix_mask) & GSO_BIT(TCPV4))
47103041	219	features &= ~NETIF_F_TSO;
82cada22 PD	220	if (~(vif->gso_mask \| vif->gso_prefix_mask) & GSO_BIT(TCPV6))
82cada22 PD	221	features &= ~NETIF_F_TSO6;
146c8a77	222	if (!vif->ip_csum)
47103041	223	features &= ~NETIF_F_IP_CSUM;
146c8a77 PD	224	if (!vif->ipv6_csum)
146c8a77 PD	225	features &= ~NETIF_F_IPV6_CSUM;
f942dc25	226
47103041	227	return features;
f942dc25 IC	228	}
	229
	230	static const struct xenvif_stat {
	231	char name[ETH_GSTRING_LEN];
	232	u16 offset;
	233	} xenvif_stats[] = {
	234	{
	235	"rx_gso_checksum_fixup",
	236	offsetof(struct xenvif, rx_gso_checksum_fixup)
	237	},
	238	};
	239
	240	static int xenvif_get_sset_count(struct net_device *dev, int string_set)
	241	{
	242	switch (string_set) {
	243	case ETH_SS_STATS:
	244	return ARRAY_SIZE(xenvif_stats);
	245	default:
	246	return -EINVAL;
	247	}
	248	}
	249
	250	static void xenvif_get_ethtool_stats(struct net_device *dev,
	251	struct ethtool_stats stats, u64 data)
	252	{
	253	void *vif = netdev_priv(dev);
	254	int i;
	255
	256	for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
	257	data[i] = (unsigned long )(vif + xenvif_stats[i].offset);
	258	}
	259
	260	static void xenvif_get_strings(struct net_device dev, u32 stringset, u8 data)
	261	{
	262	int i;
	263
	264	switch (stringset) {
	265	case ETH_SS_STATS:
	266	for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
	267	memcpy(data + i * ETH_GSTRING_LEN,
	268	xenvif_stats[i].name, ETH_GSTRING_LEN);
	269	break;
	270	}
	271	}
	272
813abbba	273	static const struct ethtool_ops xenvif_ethtool_ops = {
f942dc25 IC	274	.get_link = ethtool_op_get_link,
	275
	276	.get_sset_count = xenvif_get_sset_count,
	277	.get_ethtool_stats = xenvif_get_ethtool_stats,
	278	.get_strings = xenvif_get_strings,
	279	};
	280
813abbba	281	static const struct net_device_ops xenvif_netdev_ops = {
f942dc25 IC	282	.ndo_start_xmit = xenvif_start_xmit,
	283	.ndo_get_stats = xenvif_get_stats,
	284	.ndo_open = xenvif_open,
	285	.ndo_stop = xenvif_close,
	286	.ndo_change_mtu = xenvif_change_mtu,
47103041	287	.ndo_fix_features = xenvif_fix_features,
4a633a60 MW	288	.ndo_set_mac_address = eth_mac_addr,
4a633a60 MW	289	.ndo_validate_addr = eth_validate_addr,
f942dc25 IC	290	};
	291
	292	struct xenvif xenvif_alloc(struct device parent, domid_t domid,
	293	unsigned int handle)
	294	{
	295	int err;
	296	struct net_device *dev;
	297	struct xenvif *vif;
	298	char name[IFNAMSIZ] = {};
b3f980bd	299	int i;
f942dc25 IC	300
	301	snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
	302	dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
	303	if (dev == NULL) {
b3f980bd	304	pr_warn("Could not allocate netdev for %s\n", name);
f942dc25 IC	305	return ERR_PTR(-ENOMEM);
	306	}
	307
	308	SET_NETDEV_DEV(dev, parent);
	309
	310	vif = netdev_priv(dev);
ac3d5ac2 PD	311
	312	vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
	313	MAX_GRANT_COPY_OPS);
	314	if (vif->grant_copy_op == NULL) {
	315	pr_warn("Could not allocate grant copy space for %s\n", name);
	316	free_netdev(dev);
	317	return ERR_PTR(-ENOMEM);
	318	}
	319
f942dc25 IC	320	vif->domid = domid;
f942dc25 IC	321	vif->handle = handle;
f942dc25	322	vif->can_sg = 1;
146c8a77	323	vif->ip_csum = 1;
f942dc25	324	vif->dev = dev;
f942dc25 IC	325
	326	vif->credit_bytes = vif->remaining_credit = ~0UL;
	327	vif->credit_usec = 0UL;
	328	init_timer(&vif->credit_timeout);
059dfa6a	329	vif->credit_window_start = get_jiffies_64();
f942dc25 IC	330
f942dc25 IC	331	dev->netdev_ops = &xenvif_netdev_ops;
146c8a77 PD	332	dev->hw_features = NETIF_F_SG \|
146c8a77 PD	333	NETIF_F_IP_CSUM \| NETIF_F_IPV6_CSUM \|
82cada22	334	NETIF_F_TSO \| NETIF_F_TSO6;
7365bcfa	335	dev->features = dev->hw_features \| NETIF_F_RXCSUM;
f942dc25 IC	336	SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
	337
	338	dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
	339
b3f980bd WL	340	skb_queue_head_init(&vif->rx_queue);
	341	skb_queue_head_init(&vif->tx_queue);
	342
	343	vif->pending_cons = 0;
	344	vif->pending_prod = MAX_PENDING_REQS;
	345	for (i = 0; i < MAX_PENDING_REQS; i++)
	346	vif->pending_ring[i] = i;
	347	for (i = 0; i < MAX_PENDING_REQS; i++)
	348	vif->mmap_pages[i] = NULL;
	349
f942dc25 IC	350	/*
	351	* Initialise a dummy MAC address. We choose the numerically
	352	* largest non-broadcast address to prevent the address getting
	353	* stolen by an Ethernet bridge for STP purposes.
	354	* (FE:FF:FF:FF:FF:FF)
	355	*/
	356	memset(dev->dev_addr, 0xFF, ETH_ALEN);
	357	dev->dev_addr[0] &= ~0x01;
	358
b3f980bd WL	359	netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);
b3f980bd WL	360
f942dc25 IC	361	netif_carrier_off(dev);
	362
	363	err = register_netdev(dev);
	364	if (err) {
	365	netdev_warn(dev, "Could not register device: err=%d\n", err);
	366	free_netdev(dev);
	367	return ERR_PTR(err);
	368	}
	369
	370	netdev_dbg(dev, "Successfully created xenvif\n");
279f438e PD	371
	372	__module_get(THIS_MODULE);
	373
f942dc25 IC	374	return vif;
	375	}
	376
	377	int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
e1f00a69 WL	378	unsigned long rx_ring_ref, unsigned int tx_evtchn,
e1f00a69 WL	379	unsigned int rx_evtchn)
f942dc25	380	{
67fa3660	381	struct task_struct *task;
f942dc25 IC	382	int err = -ENOMEM;
f942dc25 IC	383
67fa3660 PD	384	BUG_ON(vif->tx_irq);
67fa3660 PD	385	BUG_ON(vif->task);
f942dc25	386
7376419a	387	err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
f942dc25 IC	388	if (err < 0)
	389	goto err;
	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
b3f980bd	423	init_waitqueue_head(&vif->wq);
67fa3660 PD	424	task = kthread_create(xenvif_kthread,
	425	(void *)vif, "%s", vif->dev->name);
	426	if (IS_ERR(task)) {
b3f980bd	427	pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
67fa3660	428	err = PTR_ERR(task);
b3f980bd WL	429	goto err_rx_unbind;
b3f980bd WL	430	}
f942dc25	431
67fa3660 PD	432	vif->task = task;
67fa3660 PD	433
f942dc25	434	rtnl_lock();
47103041 MM	435	if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
	436	dev_set_mtu(vif->dev, ETH_DATA_LEN);
	437	netdev_update_features(vif->dev);
	438	netif_carrier_on(vif->dev);
d0e5d832 DV	439	if (netif_running(vif->dev))
d0e5d832 DV	440	xenvif_up(vif);
f942dc25 IC	441	rtnl_unlock();
f942dc25 IC	442
b3f980bd WL	443	wake_up_process(vif->task);
b3f980bd WL	444
f942dc25	445	return 0;
b3f980bd WL	446
	447	err_rx_unbind:
	448	unbind_from_irqhandler(vif->rx_irq, vif);
	449	vif->rx_irq = 0;
e1f00a69 WL	450	err_tx_unbind:
	451	unbind_from_irqhandler(vif->tx_irq, vif);
	452	vif->tx_irq = 0;
f942dc25	453	err_unmap:
7376419a	454	xenvif_unmap_frontend_rings(vif);
f942dc25	455	err:
b103f358	456	module_put(THIS_MODULE);
f942dc25 IC	457	return err;
	458	}
	459
48856286	460	void xenvif_carrier_off(struct xenvif *vif)
f942dc25 IC	461	{
f942dc25 IC	462	struct net_device *dev = vif->dev;
48856286 IC	463
	464	rtnl_lock();
	465	netif_carrier_off(dev); /* discard queued packets */
	466	if (netif_running(dev))
	467	xenvif_down(vif);
	468	rtnl_unlock();
48856286 IC	469	}
	470
	471	void xenvif_disconnect(struct xenvif *vif)
	472	{
	473	if (netif_carrier_ok(vif->dev))
	474	xenvif_carrier_off(vif);
f942dc25	475
67fa3660	476	if (vif->task) {
db739ef3	477	kthread_stop(vif->task);
67fa3660 PD	478	vif->task = NULL;
67fa3660 PD	479	}
db739ef3	480
e1f00a69 WL	481	if (vif->tx_irq) {
	482	if (vif->tx_irq == vif->rx_irq)
	483	unbind_from_irqhandler(vif->tx_irq, vif);
	484	else {
	485	unbind_from_irqhandler(vif->tx_irq, vif);
	486	unbind_from_irqhandler(vif->rx_irq, vif);
	487	}
279f438e	488	vif->tx_irq = 0;
b103f358	489	}
f942dc25	490
279f438e PD	491	xenvif_unmap_frontend_rings(vif);
	492	}
	493
	494	void xenvif_free(struct xenvif *vif)
	495	{
b3f980bd WL	496	netif_napi_del(&vif->napi);
b3f980bd WL	497
f942dc25 IC	498	unregister_netdev(vif->dev);
f942dc25 IC	499
ac3d5ac2	500	vfree(vif->grant_copy_op);
f942dc25	501	free_netdev(vif->dev);
b103f358	502
279f438e	503	module_put(THIS_MODULE);
f942dc25	504	}