| /* |
| * 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 <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->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); |
| |
| free_netdev(vif->dev); |
| |
| module_put(THIS_MODULE); |
| } |