|  | /* | 
|  | * 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 u32 xenvif_fix_features(struct net_device *dev, u32 features) | 
|  | { | 
|  | struct xenvif *vif = netdev_priv(dev); | 
|  |  | 
|  | 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; | 
|  |  | 
|  | 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 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 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, | 
|  | }; | 
|  |  | 
|  | 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; | 
|  | dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO; | 
|  | dev->features = dev->hw_features; | 
|  | 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; | 
|  |  | 
|  | 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(); | 
|  | 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(); | 
|  |  | 
|  | 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); | 
|  | } |