/*
* 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/ethtool.h>
#include <linux/rtnetlink.h>
#include <linux/if_vlan.h>
#include <xen/events.h>
#include <asm/xen/hypercall.h>
#define XENVIF_QUEUE_LENGTH 32
void xenvif_get(struct xenvif *vif)
{
atomic_inc(&vif->refcnt);
}
void xenvif_put(struct xenvif *vif)
{
if (atomic_dec_and_test(&vif->refcnt))
wake_up(&vif->waiting_to_free);
}
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) && !xen_netbk_rx_ring_full(vif);
}
static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
{
struct xenvif *vif = dev_id;
if (vif->netbk == NULL)
return IRQ_NONE;
xen_netbk_schedule_xenvif(vif);
if (xenvif_rx_schedulable(vif))
netif_wake_queue(vif->dev);
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);
if (vif->netbk == 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 += xen_netbk_count_skb_slots(vif, skb);
xenvif_get(vif);
if (vif->can_queue && xen_netbk_must_stop_queue(vif))
netif_stop_queue(dev);
xen_netbk_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_receive_skb(struct xenvif *vif, struct sk_buff *skb)
{
netif_rx_ni(skb);
}
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)
{
xen_netbk_add_xenvif(vif);
enable_irq(vif->irq);
xen_netbk_check_rx_xenvif(vif);
}
static void xenvif_down(struct xenvif *vif)
{
disable_irq(vif->irq);
xen_netbk_deschedule_xenvif(vif);
xen_netbk_remove_xenvif(vif);
}
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 void xenvif_set_features(struct xenvif *vif)
{
struct net_device *dev = vif->dev;
u32 features = dev->features;
if (vif->can_sg)
features |= NETIF_F_SG;
if (vif->gso || vif->gso_prefix)
features |= NETIF_F_TSO;
if (vif->csum)
features |= NETIF_F_IP_CSUM;
features &= ~(vif->features_disabled);
if (!(features & NETIF_F_SG) && dev->mtu > ETH_DATA_LEN)
dev->mtu = ETH_DATA_LEN;
dev->features = features;
}
static int xenvif_set_tx_csum(struct net_device *dev, u32 data)
{
struct xenvif *vif = netdev_priv(dev);
if (data) {
if (!vif->csum)
return -EOPNOTSUPP;
vif->features_disabled &= ~NETIF_F_IP_CSUM;
} else {
vif->features_disabled |= NETIF_F_IP_CSUM;
}
xenvif_set_features(vif);
return 0;
}
static int xenvif_set_sg(struct net_device *dev, u32 data)
{
struct xenvif *vif = netdev_priv(dev);
if (data) {
if (!vif->can_sg)
return -EOPNOTSUPP;
vif->features_disabled &= ~NETIF_F_SG;
} else {
vif->features_disabled |= NETIF_F_SG;
}
xenvif_set_features(vif);
return 0;
}
static int xenvif_set_tso(struct net_device *dev, u32 data)
{
struct xenvif *vif = netdev_priv(dev);
if (data) {
if (!vif->gso && !vif->gso_prefix)
return -EOPNOTSUPP;
vif->features_disabled &= ~NETIF_F_TSO;
} else {
vif->features_disabled |= NETIF_F_TSO;
}
xenvif_set_features(vif);
return 0;
}
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 struct ethtool_ops xenvif_ethtool_ops = {
.get_tx_csum = ethtool_op_get_tx_csum,
.set_tx_csum = xenvif_set_tx_csum,
.get_sg = ethtool_op_get_sg,
.set_sg = xenvif_set_sg,
.get_tso = ethtool_op_get_tso,
.set_tso = xenvif_set_tso,
.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 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,
};
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] = {};
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\n");
return ERR_PTR(-ENOMEM);
}
SET_NETDEV_DEV(dev, parent);
vif = netdev_priv(dev);
vif->domid = domid;
vif->handle = handle;
vif->netbk = NULL;
vif->can_sg = 1;
vif->csum = 1;
atomic_set(&vif->refcnt, 1);
init_waitqueue_head(&vif->waiting_to_free);
vif->dev = dev;
INIT_LIST_HEAD(&vif->schedule_list);
INIT_LIST_HEAD(&vif->notify_list);
vif->credit_bytes = vif->remaining_credit = ~0UL;
vif->credit_usec = 0UL;
init_timer(&vif->credit_timeout);
/* Initialize 'expires' now: it's used to track the credit window. */
vif->credit_timeout.expires = jiffies;
dev->netdev_ops = &xenvif_netdev_ops;
xenvif_set_features(vif);
SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
/*
* 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_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");
return vif;
}
int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
unsigned long rx_ring_ref, unsigned int evtchn)
{
int err = -ENOMEM;
/* Already connected through? */
if (vif->irq)
return 0;
xenvif_set_features(vif);
err = xen_netbk_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
if (err < 0)
goto err;
err = bind_interdomain_evtchn_to_irqhandler(
vif->domid, evtchn, xenvif_interrupt, 0,
vif->dev->name, vif);
if (err < 0)
goto err_unmap;
vif->irq = err;
disable_irq(vif->irq);
xenvif_get(vif);
rtnl_lock();
netif_carrier_on(vif->dev);
if (netif_running(vif->dev))
xenvif_up(vif);
rtnl_unlock();
return 0;
err_unmap:
xen_netbk_unmap_frontend_rings(vif);
err:
return err;
}
void xenvif_disconnect(struct xenvif *vif)
{
struct net_device *dev = vif->dev;
if (netif_carrier_ok(dev)) {
rtnl_lock();
netif_carrier_off(dev); /* discard queued packets */
if (netif_running(dev))
xenvif_down(vif);
rtnl_unlock();
xenvif_put(vif);
}
atomic_dec(&vif->refcnt);
wait_event(vif->waiting_to_free, atomic_read(&vif->refcnt) == 0);
del_timer_sync(&vif->credit_timeout);
if (vif->irq)
unbind_from_irqhandler(vif->irq, vif);
unregister_netdev(vif->dev);
xen_netbk_unmap_frontend_rings(vif);
free_netdev(vif->dev);
}
