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 int xenvif_rx_schedulable(struct xenvif *vif)
52 return xenvif_schedulable(vif) && !xenvif_rx_ring_full(vif);
55 static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
57 struct xenvif *vif = dev_id;
59 if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
60 napi_schedule(&vif->napi);
65 static int xenvif_poll(struct napi_struct *napi, int budget)
67 struct xenvif *vif = container_of(napi, struct xenvif, napi);
70 work_done = xenvif_tx_action(vif, budget);
72 if (work_done < budget) {
76 /* It is necessary to disable IRQ before calling
77 * RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
78 * lose event from the frontend.
81 * RING_HAS_UNCONSUMED_REQUESTS
82 * <frontend generates event to trigger napi_schedule>
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.
92 local_irq_save(flags);
94 RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
96 __napi_complete(napi);
98 local_irq_restore(flags);
104 static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
106 struct xenvif *vif = dev_id;
108 if (xenvif_rx_schedulable(vif))
109 netif_wake_queue(vif->dev);
114 static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
116 xenvif_tx_interrupt(irq, dev_id);
117 xenvif_rx_interrupt(irq, dev_id);
122 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
124 struct xenvif *vif = netdev_priv(dev);
126 BUG_ON(skb->dev != dev);
128 /* Drop the packet if vif is not ready */
129 if (vif->task == NULL)
132 /* Drop the packet if the target domain has no receive buffers. */
133 if (!xenvif_rx_schedulable(vif))
136 /* Reserve ring slots for the worst-case number of fragments. */
137 vif->rx_req_cons_peek += xenvif_count_skb_slots(vif, skb);
139 if (vif->can_queue && xenvif_must_stop_queue(vif))
140 netif_stop_queue(dev);
142 xenvif_queue_tx_skb(vif, skb);
147 vif->dev->stats.tx_dropped++;
152 void xenvif_notify_tx_completion(struct xenvif *vif)
154 if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
155 netif_wake_queue(vif->dev);
158 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
160 struct xenvif *vif = netdev_priv(dev);
161 return &vif->dev->stats;
164 static void xenvif_up(struct xenvif *vif)
166 napi_enable(&vif->napi);
167 enable_irq(vif->tx_irq);
168 if (vif->tx_irq != vif->rx_irq)
169 enable_irq(vif->rx_irq);
170 xenvif_check_rx_xenvif(vif);
173 static void xenvif_down(struct xenvif *vif)
175 napi_disable(&vif->napi);
176 disable_irq(vif->tx_irq);
177 if (vif->tx_irq != vif->rx_irq)
178 disable_irq(vif->rx_irq);
179 del_timer_sync(&vif->credit_timeout);
182 static int xenvif_open(struct net_device *dev)
184 struct xenvif *vif = netdev_priv(dev);
185 if (netif_carrier_ok(dev))
187 netif_start_queue(dev);
191 static int xenvif_close(struct net_device *dev)
193 struct xenvif *vif = netdev_priv(dev);
194 if (netif_carrier_ok(dev))
196 netif_stop_queue(dev);
200 static int xenvif_change_mtu(struct net_device *dev, int mtu)
202 struct xenvif *vif = netdev_priv(dev);
203 int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
211 static netdev_features_t xenvif_fix_features(struct net_device *dev,
212 netdev_features_t features)
214 struct xenvif *vif = netdev_priv(dev);
217 features &= ~NETIF_F_SG;
218 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
219 features &= ~NETIF_F_TSO;
220 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
221 features &= ~NETIF_F_TSO6;
223 features &= ~NETIF_F_IP_CSUM;
225 features &= ~NETIF_F_IPV6_CSUM;
230 static const struct xenvif_stat {
231 char name[ETH_GSTRING_LEN];
235 "rx_gso_checksum_fixup",
236 offsetof(struct xenvif, rx_gso_checksum_fixup)
240 static int xenvif_get_sset_count(struct net_device *dev, int string_set)
242 switch (string_set) {
244 return ARRAY_SIZE(xenvif_stats);
250 static void xenvif_get_ethtool_stats(struct net_device *dev,
251 struct ethtool_stats *stats, u64 * data)
253 void *vif = netdev_priv(dev);
256 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
257 data[i] = *(unsigned long *)(vif + xenvif_stats[i].offset);
260 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
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);
273 static const struct ethtool_ops xenvif_ethtool_ops = {
274 .get_link = ethtool_op_get_link,
276 .get_sset_count = xenvif_get_sset_count,
277 .get_ethtool_stats = xenvif_get_ethtool_stats,
278 .get_strings = xenvif_get_strings,
281 static const struct net_device_ops xenvif_netdev_ops = {
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,
287 .ndo_fix_features = xenvif_fix_features,
288 .ndo_set_mac_address = eth_mac_addr,
289 .ndo_validate_addr = eth_validate_addr,
292 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
296 struct net_device *dev;
298 char name[IFNAMSIZ] = {};
301 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
302 dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
304 pr_warn("Could not allocate netdev for %s\n", name);
305 return ERR_PTR(-ENOMEM);
308 SET_NETDEV_DEV(dev, parent);
310 vif = netdev_priv(dev);
312 vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
314 if (vif->grant_copy_op == NULL) {
315 pr_warn("Could not allocate grant copy space for %s\n", name);
317 return ERR_PTR(-ENOMEM);
321 vif->handle = handle;
326 vif->credit_bytes = vif->remaining_credit = ~0UL;
327 vif->credit_usec = 0UL;
328 init_timer(&vif->credit_timeout);
329 vif->credit_window_start = get_jiffies_64();
331 dev->netdev_ops = &xenvif_netdev_ops;
332 dev->hw_features = NETIF_F_SG |
333 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
334 NETIF_F_TSO | NETIF_F_TSO6;
335 dev->features = dev->hw_features | NETIF_F_RXCSUM;
336 SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
338 dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
340 skb_queue_head_init(&vif->rx_queue);
341 skb_queue_head_init(&vif->tx_queue);
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;
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)
356 memset(dev->dev_addr, 0xFF, ETH_ALEN);
357 dev->dev_addr[0] &= ~0x01;
359 netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);
361 netif_carrier_off(dev);
363 err = register_netdev(dev);
365 netdev_warn(dev, "Could not register device: err=%d\n", err);
370 netdev_dbg(dev, "Successfully created xenvif\n");
372 __module_get(THIS_MODULE);
377 int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
378 unsigned long rx_ring_ref, unsigned int tx_evtchn,
379 unsigned int rx_evtchn)
381 struct task_struct *task;
387 err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
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 init_waitqueue_head(&vif->wq);
424 task = kthread_create(xenvif_kthread,
425 (void *)vif, "%s", vif->dev->name);
427 pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
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);
439 if (netif_running(vif->dev))
443 wake_up_process(vif->task);
448 unbind_from_irqhandler(vif->rx_irq, vif);
451 unbind_from_irqhandler(vif->tx_irq, vif);
454 xenvif_unmap_frontend_rings(vif);
456 module_put(THIS_MODULE);
460 void xenvif_carrier_off(struct xenvif *vif)
462 struct net_device *dev = vif->dev;
465 netif_carrier_off(dev); /* discard queued packets */
466 if (netif_running(dev))
471 void xenvif_disconnect(struct xenvif *vif)
473 if (netif_carrier_ok(vif->dev))
474 xenvif_carrier_off(vif);
477 kthread_stop(vif->task);
482 if (vif->tx_irq == vif->rx_irq)
483 unbind_from_irqhandler(vif->tx_irq, vif);
485 unbind_from_irqhandler(vif->tx_irq, vif);
486 unbind_from_irqhandler(vif->rx_irq, vif);
491 xenvif_unmap_frontend_rings(vif);
494 void xenvif_free(struct xenvif *vif)
496 netif_napi_del(&vif->napi);
498 unregister_netdev(vif->dev);
500 vfree(vif->grant_copy_op);
501 free_netdev(vif->dev);
503 module_put(THIS_MODULE);