2 * Network-device interface management.
4 * Copyright (c) 2004-2005, Keir Fraser
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:
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:
19 * The above copyright notice and this permission notice shall be included in
20 * all copies or substantial portions of the Software.
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
33 #include <linux/kthread.h>
34 #include <linux/ethtool.h>
35 #include <linux/rtnetlink.h>
36 #include <linux/if_vlan.h>
37 #include <linux/vmalloc.h>
39 #include <xen/events.h>
40 #include <asm/xen/hypercall.h>
42 #define XENVIF_QUEUE_LENGTH 32
43 #define XENVIF_NAPI_WEIGHT 64
45 int xenvif_schedulable(struct xenvif *vif)
47 return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
50 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
52 struct xenvif *vif = dev_id;
54 if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
55 napi_schedule(&vif->napi);
60 static int xenvif_poll(struct napi_struct *napi, int budget)
62 struct xenvif *vif = container_of(napi, struct xenvif, napi);
65 work_done = xenvif_tx_action(vif, budget);
67 if (work_done < budget) {
71 /* It is necessary to disable IRQ before calling
72 * RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
73 * lose event from the frontend.
76 * RING_HAS_UNCONSUMED_REQUESTS
77 * <frontend generates event to trigger napi_schedule>
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.
87 local_irq_save(flags);
89 RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
91 __napi_complete(napi);
93 local_irq_restore(flags);
99 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
101 struct xenvif *vif = dev_id;
103 xenvif_kick_thread(vif);
108 static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
110 xenvif_tx_interrupt(irq, dev_id);
111 xenvif_rx_interrupt(irq, dev_id);
116 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
118 struct xenvif *vif = netdev_priv(dev);
119 int min_slots_needed;
121 BUG_ON(skb->dev != dev);
123 /* Drop the packet if vif is not ready */
124 if (vif->task == NULL || !xenvif_schedulable(vif))
127 /* At best we'll need one slot for the header and one for each
130 min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;
132 /* If the skb is GSO then we'll also need an extra slot for the
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
142 if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
143 xenvif_stop_queue(vif);
145 skb_queue_tail(&vif->rx_queue, skb);
146 xenvif_kick_thread(vif);
151 vif->dev->stats.tx_dropped++;
156 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
158 struct xenvif *vif = netdev_priv(dev);
159 return &vif->dev->stats;
162 static void xenvif_up(struct xenvif *vif)
164 napi_enable(&vif->napi);
165 enable_irq(vif->tx_irq);
166 if (vif->tx_irq != vif->rx_irq)
167 enable_irq(vif->rx_irq);
168 xenvif_check_rx_xenvif(vif);
171 static void xenvif_down(struct xenvif *vif)
173 napi_disable(&vif->napi);
174 disable_irq(vif->tx_irq);
175 if (vif->tx_irq != vif->rx_irq)
176 disable_irq(vif->rx_irq);
177 del_timer_sync(&vif->credit_timeout);
180 static int xenvif_open(struct net_device *dev)
182 struct xenvif *vif = netdev_priv(dev);
183 if (netif_carrier_ok(dev))
185 netif_start_queue(dev);
189 static int xenvif_close(struct net_device *dev)
191 struct xenvif *vif = netdev_priv(dev);
192 if (netif_carrier_ok(dev))
194 netif_stop_queue(dev);
198 static int xenvif_change_mtu(struct net_device *dev, int mtu)
200 struct xenvif *vif = netdev_priv(dev);
201 int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
209 static netdev_features_t xenvif_fix_features(struct net_device *dev,
210 netdev_features_t features)
212 struct xenvif *vif = netdev_priv(dev);
215 features &= ~NETIF_F_SG;
216 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
217 features &= ~NETIF_F_TSO;
218 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
219 features &= ~NETIF_F_TSO6;
221 features &= ~NETIF_F_IP_CSUM;
223 features &= ~NETIF_F_IPV6_CSUM;
228 static const struct xenvif_stat {
229 char name[ETH_GSTRING_LEN];
233 "rx_gso_checksum_fixup",
234 offsetof(struct xenvif, rx_gso_checksum_fixup)
238 static int xenvif_get_sset_count(struct net_device *dev, int string_set)
240 switch (string_set) {
242 return ARRAY_SIZE(xenvif_stats);
248 static void xenvif_get_ethtool_stats(struct net_device *dev,
249 struct ethtool_stats *stats, u64 * data)
251 void *vif = netdev_priv(dev);
254 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
255 data[i] = *(unsigned long *)(vif + xenvif_stats[i].offset);
258 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
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);
271 static const struct ethtool_ops xenvif_ethtool_ops = {
272 .get_link = ethtool_op_get_link,
274 .get_sset_count = xenvif_get_sset_count,
275 .get_ethtool_stats = xenvif_get_ethtool_stats,
276 .get_strings = xenvif_get_strings,
279 static const struct net_device_ops xenvif_netdev_ops = {
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,
285 .ndo_fix_features = xenvif_fix_features,
286 .ndo_set_mac_address = eth_mac_addr,
287 .ndo_validate_addr = eth_validate_addr,
290 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
294 struct net_device *dev;
296 char name[IFNAMSIZ] = {};
299 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
300 dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
302 pr_warn("Could not allocate netdev for %s\n", name);
303 return ERR_PTR(-ENOMEM);
306 SET_NETDEV_DEV(dev, parent);
308 vif = netdev_priv(dev);
310 vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
312 if (vif->grant_copy_op == NULL) {
313 pr_warn("Could not allocate grant copy space for %s\n", name);
315 return ERR_PTR(-ENOMEM);
319 vif->handle = handle;
324 vif->credit_bytes = vif->remaining_credit = ~0UL;
325 vif->credit_usec = 0UL;
326 init_timer(&vif->credit_timeout);
327 vif->credit_window_start = get_jiffies_64();
329 dev->netdev_ops = &xenvif_netdev_ops;
330 dev->hw_features = NETIF_F_SG |
331 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
332 NETIF_F_TSO | NETIF_F_TSO6;
333 dev->features = dev->hw_features | NETIF_F_RXCSUM;
334 SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
336 dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
338 skb_queue_head_init(&vif->rx_queue);
339 skb_queue_head_init(&vif->tx_queue);
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;
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)
354 memset(dev->dev_addr, 0xFF, ETH_ALEN);
355 dev->dev_addr[0] &= ~0x01;
357 netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);
359 netif_carrier_off(dev);
361 err = register_netdev(dev);
363 netdev_warn(dev, "Could not register device: err=%d\n", err);
368 netdev_dbg(dev, "Successfully created xenvif\n");
370 __module_get(THIS_MODULE);
375 int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
376 unsigned long rx_ring_ref, unsigned int tx_evtchn,
377 unsigned int rx_evtchn)
379 struct task_struct *task;
385 err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
389 init_waitqueue_head(&vif->wq);
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);
398 vif->tx_irq = vif->rx_irq = err;
399 disable_irq(vif->tx_irq);
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);
410 disable_irq(vif->tx_irq);
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);
420 disable_irq(vif->rx_irq);
423 task = kthread_create(xenvif_kthread,
424 (void *)vif, "%s", vif->dev->name);
426 pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
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);
438 if (netif_running(vif->dev))
442 wake_up_process(vif->task);
447 unbind_from_irqhandler(vif->rx_irq, vif);
450 unbind_from_irqhandler(vif->tx_irq, vif);
453 xenvif_unmap_frontend_rings(vif);
455 module_put(THIS_MODULE);
459 void xenvif_carrier_off(struct xenvif *vif)
461 struct net_device *dev = vif->dev;
464 netif_carrier_off(dev); /* discard queued packets */
465 if (netif_running(dev))
470 void xenvif_disconnect(struct xenvif *vif)
472 if (netif_carrier_ok(vif->dev))
473 xenvif_carrier_off(vif);
476 kthread_stop(vif->task);
481 if (vif->tx_irq == vif->rx_irq)
482 unbind_from_irqhandler(vif->tx_irq, vif);
484 unbind_from_irqhandler(vif->tx_irq, vif);
485 unbind_from_irqhandler(vif->rx_irq, vif);
490 xenvif_unmap_frontend_rings(vif);
493 void xenvif_free(struct xenvif *vif)
495 netif_napi_del(&vif->napi);
497 unregister_netdev(vif->dev);
499 vfree(vif->grant_copy_op);
500 free_netdev(vif->dev);
502 module_put(THIS_MODULE);