Add linux-next specific files for 20110831
[linux-2.6/next.git] / drivers / net / xen-netback / interface.c
blob0ca86f9ec4ed38531b0d59060d8f9fa49024dee6
1 /*
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
28 * IN THE SOFTWARE.
31 #include "common.h"
33 #include <linux/ethtool.h>
34 #include <linux/rtnetlink.h>
35 #include <linux/if_vlan.h>
37 #include <xen/events.h>
38 #include <asm/xen/hypercall.h>
40 #define XENVIF_QUEUE_LENGTH 32
42 void xenvif_get(struct xenvif *vif)
44 atomic_inc(&vif->refcnt);
47 void xenvif_put(struct xenvif *vif)
49 if (atomic_dec_and_test(&vif->refcnt))
50 wake_up(&vif->waiting_to_free);
53 int xenvif_schedulable(struct xenvif *vif)
55 return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
58 static int xenvif_rx_schedulable(struct xenvif *vif)
60 return xenvif_schedulable(vif) && !xen_netbk_rx_ring_full(vif);
63 static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
65 struct xenvif *vif = dev_id;
67 if (vif->netbk == NULL)
68 return IRQ_NONE;
70 xen_netbk_schedule_xenvif(vif);
72 if (xenvif_rx_schedulable(vif))
73 netif_wake_queue(vif->dev);
75 return IRQ_HANDLED;
78 static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
80 struct xenvif *vif = netdev_priv(dev);
82 BUG_ON(skb->dev != dev);
84 if (vif->netbk == NULL)
85 goto drop;
87 /* Drop the packet if the target domain has no receive buffers. */
88 if (!xenvif_rx_schedulable(vif))
89 goto drop;
91 /* Reserve ring slots for the worst-case number of fragments. */
92 vif->rx_req_cons_peek += xen_netbk_count_skb_slots(vif, skb);
93 xenvif_get(vif);
95 if (vif->can_queue && xen_netbk_must_stop_queue(vif))
96 netif_stop_queue(dev);
98 xen_netbk_queue_tx_skb(vif, skb);
100 return NETDEV_TX_OK;
102 drop:
103 vif->dev->stats.tx_dropped++;
104 dev_kfree_skb(skb);
105 return NETDEV_TX_OK;
108 void xenvif_receive_skb(struct xenvif *vif, struct sk_buff *skb)
110 netif_rx_ni(skb);
113 void xenvif_notify_tx_completion(struct xenvif *vif)
115 if (netif_queue_stopped(vif->dev) && xenvif_rx_schedulable(vif))
116 netif_wake_queue(vif->dev);
119 static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
121 struct xenvif *vif = netdev_priv(dev);
122 return &vif->dev->stats;
125 static void xenvif_up(struct xenvif *vif)
127 xen_netbk_add_xenvif(vif);
128 enable_irq(vif->irq);
129 xen_netbk_check_rx_xenvif(vif);
132 static void xenvif_down(struct xenvif *vif)
134 disable_irq(vif->irq);
135 xen_netbk_deschedule_xenvif(vif);
136 xen_netbk_remove_xenvif(vif);
139 static int xenvif_open(struct net_device *dev)
141 struct xenvif *vif = netdev_priv(dev);
142 if (netif_carrier_ok(dev))
143 xenvif_up(vif);
144 netif_start_queue(dev);
145 return 0;
148 static int xenvif_close(struct net_device *dev)
150 struct xenvif *vif = netdev_priv(dev);
151 if (netif_carrier_ok(dev))
152 xenvif_down(vif);
153 netif_stop_queue(dev);
154 return 0;
157 static int xenvif_change_mtu(struct net_device *dev, int mtu)
159 struct xenvif *vif = netdev_priv(dev);
160 int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
162 if (mtu > max)
163 return -EINVAL;
164 dev->mtu = mtu;
165 return 0;
168 static u32 xenvif_fix_features(struct net_device *dev, u32 features)
170 struct xenvif *vif = netdev_priv(dev);
172 if (!vif->can_sg)
173 features &= ~NETIF_F_SG;
174 if (!vif->gso && !vif->gso_prefix)
175 features &= ~NETIF_F_TSO;
176 if (!vif->csum)
177 features &= ~NETIF_F_IP_CSUM;
179 return features;
182 static const struct xenvif_stat {
183 char name[ETH_GSTRING_LEN];
184 u16 offset;
185 } xenvif_stats[] = {
187 "rx_gso_checksum_fixup",
188 offsetof(struct xenvif, rx_gso_checksum_fixup)
192 static int xenvif_get_sset_count(struct net_device *dev, int string_set)
194 switch (string_set) {
195 case ETH_SS_STATS:
196 return ARRAY_SIZE(xenvif_stats);
197 default:
198 return -EINVAL;
202 static void xenvif_get_ethtool_stats(struct net_device *dev,
203 struct ethtool_stats *stats, u64 * data)
205 void *vif = netdev_priv(dev);
206 int i;
208 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
209 data[i] = *(unsigned long *)(vif + xenvif_stats[i].offset);
212 static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
214 int i;
216 switch (stringset) {
217 case ETH_SS_STATS:
218 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
219 memcpy(data + i * ETH_GSTRING_LEN,
220 xenvif_stats[i].name, ETH_GSTRING_LEN);
221 break;
225 static struct ethtool_ops xenvif_ethtool_ops = {
226 .get_link = ethtool_op_get_link,
228 .get_sset_count = xenvif_get_sset_count,
229 .get_ethtool_stats = xenvif_get_ethtool_stats,
230 .get_strings = xenvif_get_strings,
233 static struct net_device_ops xenvif_netdev_ops = {
234 .ndo_start_xmit = xenvif_start_xmit,
235 .ndo_get_stats = xenvif_get_stats,
236 .ndo_open = xenvif_open,
237 .ndo_stop = xenvif_close,
238 .ndo_change_mtu = xenvif_change_mtu,
239 .ndo_fix_features = xenvif_fix_features,
242 struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
243 unsigned int handle)
245 int err;
246 struct net_device *dev;
247 struct xenvif *vif;
248 char name[IFNAMSIZ] = {};
250 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
251 dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
252 if (dev == NULL) {
253 pr_warn("Could not allocate netdev\n");
254 return ERR_PTR(-ENOMEM);
257 SET_NETDEV_DEV(dev, parent);
259 vif = netdev_priv(dev);
260 vif->domid = domid;
261 vif->handle = handle;
262 vif->netbk = NULL;
263 vif->can_sg = 1;
264 vif->csum = 1;
265 atomic_set(&vif->refcnt, 1);
266 init_waitqueue_head(&vif->waiting_to_free);
267 vif->dev = dev;
268 INIT_LIST_HEAD(&vif->schedule_list);
269 INIT_LIST_HEAD(&vif->notify_list);
271 vif->credit_bytes = vif->remaining_credit = ~0UL;
272 vif->credit_usec = 0UL;
273 init_timer(&vif->credit_timeout);
274 /* Initialize 'expires' now: it's used to track the credit window. */
275 vif->credit_timeout.expires = jiffies;
277 dev->netdev_ops = &xenvif_netdev_ops;
278 dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
279 dev->features = dev->hw_features;
280 SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
282 dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
285 * Initialise a dummy MAC address. We choose the numerically
286 * largest non-broadcast address to prevent the address getting
287 * stolen by an Ethernet bridge for STP purposes.
288 * (FE:FF:FF:FF:FF:FF)
290 memset(dev->dev_addr, 0xFF, ETH_ALEN);
291 dev->dev_addr[0] &= ~0x01;
293 netif_carrier_off(dev);
295 err = register_netdev(dev);
296 if (err) {
297 netdev_warn(dev, "Could not register device: err=%d\n", err);
298 free_netdev(dev);
299 return ERR_PTR(err);
302 netdev_dbg(dev, "Successfully created xenvif\n");
303 return vif;
306 int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
307 unsigned long rx_ring_ref, unsigned int evtchn)
309 int err = -ENOMEM;
311 /* Already connected through? */
312 if (vif->irq)
313 return 0;
315 err = xen_netbk_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
316 if (err < 0)
317 goto err;
319 err = bind_interdomain_evtchn_to_irqhandler(
320 vif->domid, evtchn, xenvif_interrupt, 0,
321 vif->dev->name, vif);
322 if (err < 0)
323 goto err_unmap;
324 vif->irq = err;
325 disable_irq(vif->irq);
327 xenvif_get(vif);
329 rtnl_lock();
330 if (netif_running(vif->dev))
331 xenvif_up(vif);
332 if (!vif->can_sg && vif->dev->mtu > ETH_DATA_LEN)
333 dev_set_mtu(vif->dev, ETH_DATA_LEN);
334 netdev_update_features(vif->dev);
335 netif_carrier_on(vif->dev);
336 rtnl_unlock();
338 return 0;
339 err_unmap:
340 xen_netbk_unmap_frontend_rings(vif);
341 err:
342 return err;
345 void xenvif_disconnect(struct xenvif *vif)
347 struct net_device *dev = vif->dev;
348 if (netif_carrier_ok(dev)) {
349 rtnl_lock();
350 netif_carrier_off(dev); /* discard queued packets */
351 if (netif_running(dev))
352 xenvif_down(vif);
353 rtnl_unlock();
354 xenvif_put(vif);
357 atomic_dec(&vif->refcnt);
358 wait_event(vif->waiting_to_free, atomic_read(&vif->refcnt) == 0);
360 del_timer_sync(&vif->credit_timeout);
362 if (vif->irq)
363 unbind_from_irqhandler(vif->irq, vif);
365 unregister_netdev(vif->dev);
367 xen_netbk_unmap_frontend_rings(vif);
369 free_netdev(vif->dev);