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CommitLineData
f942dc25
IC
1/*
2 * Network-device interface management.
3 *
4 * Copyright (c) 2004-2005, Keir Fraser
5 *
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:
11 *
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:
18 *
19 * The above copyright notice and this permission notice shall be included in
20 * all copies or substantial portions of the Software.
21 *
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.
29 */
30
31#include "common.h"
32
b3f980bd 33#include <linux/kthread.h>
f942dc25
IC
34#include <linux/ethtool.h>
35#include <linux/rtnetlink.h>
36#include <linux/if_vlan.h>
f35f76ee 37#include <linux/vmalloc.h>
f942dc25
IC
38
39#include <xen/events.h>
40#include <asm/xen/hypercall.h>
41
42#define XENVIF_QUEUE_LENGTH 32
b3f980bd 43#define XENVIF_NAPI_WEIGHT 64
f942dc25
IC
44
45int xenvif_schedulable(struct xenvif *vif)
46{
47 return netif_running(vif->dev) && netif_carrier_ok(vif->dev);
48}
49
e1f00a69 50static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id)
f942dc25
IC
51{
52 struct xenvif *vif = dev_id;
53
b3f980bd
WL
54 if (RING_HAS_UNCONSUMED_REQUESTS(&vif->tx))
55 napi_schedule(&vif->napi);
f942dc25 56
e1f00a69
WL
57 return IRQ_HANDLED;
58}
59
b3f980bd
WL
60static int xenvif_poll(struct napi_struct *napi, int budget)
61{
62 struct xenvif *vif = container_of(napi, struct xenvif, napi);
63 int work_done;
64
7376419a 65 work_done = xenvif_tx_action(vif, budget);
b3f980bd
WL
66
67 if (work_done < budget) {
68 int more_to_do = 0;
69 unsigned long flags;
70
71 /* It is necessary to disable IRQ before calling
72 * RING_HAS_UNCONSUMED_REQUESTS. Otherwise we might
73 * lose event from the frontend.
74 *
75 * Consider:
76 * RING_HAS_UNCONSUMED_REQUESTS
77 * <frontend generates event to trigger napi_schedule>
78 * __napi_complete
79 *
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.
85 */
86
87 local_irq_save(flags);
88
89 RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
90 if (!more_to_do)
91 __napi_complete(napi);
92
93 local_irq_restore(flags);
94 }
95
96 return work_done;
97}
98
e1f00a69
WL
99static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id)
100{
101 struct xenvif *vif = dev_id;
102
ca2f09f2 103 xenvif_kick_thread(vif);
f942dc25
IC
104
105 return IRQ_HANDLED;
106}
107
e1f00a69
WL
108static irqreturn_t xenvif_interrupt(int irq, void *dev_id)
109{
110 xenvif_tx_interrupt(irq, dev_id);
111 xenvif_rx_interrupt(irq, dev_id);
112
113 return IRQ_HANDLED;
114}
115
f942dc25
IC
116static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
117{
118 struct xenvif *vif = netdev_priv(dev);
ca2f09f2 119 int min_slots_needed;
f942dc25
IC
120
121 BUG_ON(skb->dev != dev);
122
b3f980bd 123 /* Drop the packet if vif is not ready */
ca2f09f2 124 if (vif->task == NULL || !xenvif_schedulable(vif))
f942dc25
IC
125 goto drop;
126
ca2f09f2
PD
127 /* At best we'll need one slot for the header and one for each
128 * frag.
129 */
130 min_slots_needed = 1 + skb_shinfo(skb)->nr_frags;
f942dc25 131
ca2f09f2
PD
132 /* If the skb is GSO then we'll also need an extra slot for the
133 * metadata.
134 */
135 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
136 skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
137 min_slots_needed++;
f942dc25 138
ca2f09f2
PD
139 /* If the skb can't possibly fit in the remaining slots
140 * then turn off the queue to give the ring a chance to
141 * drain.
142 */
143 if (!xenvif_rx_ring_slots_available(vif, min_slots_needed))
144 xenvif_stop_queue(vif);
f942dc25 145
ca2f09f2
PD
146 skb_queue_tail(&vif->rx_queue, skb);
147 xenvif_kick_thread(vif);
f942dc25
IC
148
149 return NETDEV_TX_OK;
150
151 drop:
152 vif->dev->stats.tx_dropped++;
153 dev_kfree_skb(skb);
154 return NETDEV_TX_OK;
155}
156
f942dc25
IC
157static struct net_device_stats *xenvif_get_stats(struct net_device *dev)
158{
159 struct xenvif *vif = netdev_priv(dev);
160 return &vif->dev->stats;
161}
162
163static void xenvif_up(struct xenvif *vif)
164{
b3f980bd 165 napi_enable(&vif->napi);
e1f00a69
WL
166 enable_irq(vif->tx_irq);
167 if (vif->tx_irq != vif->rx_irq)
168 enable_irq(vif->rx_irq);
7376419a 169 xenvif_check_rx_xenvif(vif);
f942dc25
IC
170}
171
172static void xenvif_down(struct xenvif *vif)
173{
b3f980bd 174 napi_disable(&vif->napi);
e1f00a69
WL
175 disable_irq(vif->tx_irq);
176 if (vif->tx_irq != vif->rx_irq)
177 disable_irq(vif->rx_irq);
3e55f8b3 178 del_timer_sync(&vif->credit_timeout);
f942dc25
IC
179}
180
181static int xenvif_open(struct net_device *dev)
182{
183 struct xenvif *vif = netdev_priv(dev);
184 if (netif_carrier_ok(dev))
185 xenvif_up(vif);
186 netif_start_queue(dev);
187 return 0;
188}
189
190static int xenvif_close(struct net_device *dev)
191{
192 struct xenvif *vif = netdev_priv(dev);
193 if (netif_carrier_ok(dev))
194 xenvif_down(vif);
195 netif_stop_queue(dev);
196 return 0;
197}
198
199static int xenvif_change_mtu(struct net_device *dev, int mtu)
200{
201 struct xenvif *vif = netdev_priv(dev);
202 int max = vif->can_sg ? 65535 - VLAN_ETH_HLEN : ETH_DATA_LEN;
203
204 if (mtu > max)
205 return -EINVAL;
206 dev->mtu = mtu;
207 return 0;
208}
209
c8f44aff
MM
210static netdev_features_t xenvif_fix_features(struct net_device *dev,
211 netdev_features_t features)
f942dc25
IC
212{
213 struct xenvif *vif = netdev_priv(dev);
f942dc25 214
47103041
MM
215 if (!vif->can_sg)
216 features &= ~NETIF_F_SG;
82cada22 217 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV4))
47103041 218 features &= ~NETIF_F_TSO;
82cada22
PD
219 if (~(vif->gso_mask | vif->gso_prefix_mask) & GSO_BIT(TCPV6))
220 features &= ~NETIF_F_TSO6;
146c8a77 221 if (!vif->ip_csum)
47103041 222 features &= ~NETIF_F_IP_CSUM;
146c8a77
PD
223 if (!vif->ipv6_csum)
224 features &= ~NETIF_F_IPV6_CSUM;
f942dc25 225
47103041 226 return features;
f942dc25
IC
227}
228
229static const struct xenvif_stat {
230 char name[ETH_GSTRING_LEN];
231 u16 offset;
232} xenvif_stats[] = {
233 {
234 "rx_gso_checksum_fixup",
235 offsetof(struct xenvif, rx_gso_checksum_fixup)
236 },
237};
238
239static int xenvif_get_sset_count(struct net_device *dev, int string_set)
240{
241 switch (string_set) {
242 case ETH_SS_STATS:
243 return ARRAY_SIZE(xenvif_stats);
244 default:
245 return -EINVAL;
246 }
247}
248
249static void xenvif_get_ethtool_stats(struct net_device *dev,
250 struct ethtool_stats *stats, u64 * data)
251{
252 void *vif = netdev_priv(dev);
253 int i;
254
255 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
256 data[i] = *(unsigned long *)(vif + xenvif_stats[i].offset);
257}
258
259static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data)
260{
261 int i;
262
263 switch (stringset) {
264 case ETH_SS_STATS:
265 for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++)
266 memcpy(data + i * ETH_GSTRING_LEN,
267 xenvif_stats[i].name, ETH_GSTRING_LEN);
268 break;
269 }
270}
271
813abbba 272static const struct ethtool_ops xenvif_ethtool_ops = {
f942dc25
IC
273 .get_link = ethtool_op_get_link,
274
275 .get_sset_count = xenvif_get_sset_count,
276 .get_ethtool_stats = xenvif_get_ethtool_stats,
277 .get_strings = xenvif_get_strings,
278};
279
813abbba 280static const struct net_device_ops xenvif_netdev_ops = {
f942dc25
IC
281 .ndo_start_xmit = xenvif_start_xmit,
282 .ndo_get_stats = xenvif_get_stats,
283 .ndo_open = xenvif_open,
284 .ndo_stop = xenvif_close,
285 .ndo_change_mtu = xenvif_change_mtu,
47103041 286 .ndo_fix_features = xenvif_fix_features,
4a633a60
MW
287 .ndo_set_mac_address = eth_mac_addr,
288 .ndo_validate_addr = eth_validate_addr,
f942dc25
IC
289};
290
291struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
292 unsigned int handle)
293{
294 int err;
295 struct net_device *dev;
296 struct xenvif *vif;
297 char name[IFNAMSIZ] = {};
b3f980bd 298 int i;
f942dc25
IC
299
300 snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
301 dev = alloc_netdev(sizeof(struct xenvif), name, ether_setup);
302 if (dev == NULL) {
b3f980bd 303 pr_warn("Could not allocate netdev for %s\n", name);
f942dc25
IC
304 return ERR_PTR(-ENOMEM);
305 }
306
307 SET_NETDEV_DEV(dev, parent);
308
309 vif = netdev_priv(dev);
ac3d5ac2
PD
310
311 vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) *
312 MAX_GRANT_COPY_OPS);
313 if (vif->grant_copy_op == NULL) {
314 pr_warn("Could not allocate grant copy space for %s\n", name);
315 free_netdev(dev);
316 return ERR_PTR(-ENOMEM);
317 }
318
f942dc25
IC
319 vif->domid = domid;
320 vif->handle = handle;
f942dc25 321 vif->can_sg = 1;
146c8a77 322 vif->ip_csum = 1;
f942dc25 323 vif->dev = dev;
f942dc25
IC
324
325 vif->credit_bytes = vif->remaining_credit = ~0UL;
326 vif->credit_usec = 0UL;
327 init_timer(&vif->credit_timeout);
059dfa6a 328 vif->credit_window_start = get_jiffies_64();
f942dc25
IC
329
330 dev->netdev_ops = &xenvif_netdev_ops;
146c8a77
PD
331 dev->hw_features = NETIF_F_SG |
332 NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
82cada22 333 NETIF_F_TSO | NETIF_F_TSO6;
7365bcfa 334 dev->features = dev->hw_features | NETIF_F_RXCSUM;
f942dc25
IC
335 SET_ETHTOOL_OPS(dev, &xenvif_ethtool_ops);
336
337 dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
338
b3f980bd
WL
339 skb_queue_head_init(&vif->rx_queue);
340 skb_queue_head_init(&vif->tx_queue);
341
342 vif->pending_cons = 0;
343 vif->pending_prod = MAX_PENDING_REQS;
344 for (i = 0; i < MAX_PENDING_REQS; i++)
345 vif->pending_ring[i] = i;
346 for (i = 0; i < MAX_PENDING_REQS; i++)
347 vif->mmap_pages[i] = NULL;
348
f942dc25
IC
349 /*
350 * Initialise a dummy MAC address. We choose the numerically
351 * largest non-broadcast address to prevent the address getting
352 * stolen by an Ethernet bridge for STP purposes.
353 * (FE:FF:FF:FF:FF:FF)
354 */
355 memset(dev->dev_addr, 0xFF, ETH_ALEN);
356 dev->dev_addr[0] &= ~0x01;
357
b3f980bd
WL
358 netif_napi_add(dev, &vif->napi, xenvif_poll, XENVIF_NAPI_WEIGHT);
359
f942dc25
IC
360 netif_carrier_off(dev);
361
362 err = register_netdev(dev);
363 if (err) {
364 netdev_warn(dev, "Could not register device: err=%d\n", err);
365 free_netdev(dev);
366 return ERR_PTR(err);
367 }
368
369 netdev_dbg(dev, "Successfully created xenvif\n");
279f438e
PD
370
371 __module_get(THIS_MODULE);
372
f942dc25
IC
373 return vif;
374}
375
376int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
e1f00a69
WL
377 unsigned long rx_ring_ref, unsigned int tx_evtchn,
378 unsigned int rx_evtchn)
f942dc25 379{
67fa3660 380 struct task_struct *task;
f942dc25
IC
381 int err = -ENOMEM;
382
67fa3660
PD
383 BUG_ON(vif->tx_irq);
384 BUG_ON(vif->task);
f942dc25 385
7376419a 386 err = xenvif_map_frontend_rings(vif, tx_ring_ref, rx_ring_ref);
f942dc25
IC
387 if (err < 0)
388 goto err;
389
ca2f09f2
PD
390 init_waitqueue_head(&vif->wq);
391
e1f00a69
WL
392 if (tx_evtchn == rx_evtchn) {
393 /* feature-split-event-channels == 0 */
394 err = bind_interdomain_evtchn_to_irqhandler(
395 vif->domid, tx_evtchn, xenvif_interrupt, 0,
396 vif->dev->name, vif);
397 if (err < 0)
398 goto err_unmap;
399 vif->tx_irq = vif->rx_irq = err;
400 disable_irq(vif->tx_irq);
401 } else {
402 /* feature-split-event-channels == 1 */
403 snprintf(vif->tx_irq_name, sizeof(vif->tx_irq_name),
404 "%s-tx", vif->dev->name);
405 err = bind_interdomain_evtchn_to_irqhandler(
406 vif->domid, tx_evtchn, xenvif_tx_interrupt, 0,
407 vif->tx_irq_name, vif);
408 if (err < 0)
409 goto err_unmap;
410 vif->tx_irq = err;
411 disable_irq(vif->tx_irq);
412
413 snprintf(vif->rx_irq_name, sizeof(vif->rx_irq_name),
414 "%s-rx", vif->dev->name);
415 err = bind_interdomain_evtchn_to_irqhandler(
416 vif->domid, rx_evtchn, xenvif_rx_interrupt, 0,
417 vif->rx_irq_name, vif);
418 if (err < 0)
419 goto err_tx_unbind;
420 vif->rx_irq = err;
421 disable_irq(vif->rx_irq);
422 }
f942dc25 423
67fa3660
PD
424 task = kthread_create(xenvif_kthread,
425 (void *)vif, "%s", vif->dev->name);
426 if (IS_ERR(task)) {
b3f980bd 427 pr_warn("Could not allocate kthread for %s\n", vif->dev->name);
67fa3660 428 err = PTR_ERR(task);
b3f980bd
WL
429 goto err_rx_unbind;
430 }
f942dc25 431
67fa3660
PD
432 vif->task = task;
433
f942dc25 434 rtnl_lock();
47103041
MM
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);
d0e5d832
DV
439 if (netif_running(vif->dev))
440 xenvif_up(vif);
f942dc25
IC
441 rtnl_unlock();
442
b3f980bd
WL
443 wake_up_process(vif->task);
444
f942dc25 445 return 0;
b3f980bd
WL
446
447err_rx_unbind:
448 unbind_from_irqhandler(vif->rx_irq, vif);
449 vif->rx_irq = 0;
e1f00a69
WL
450err_tx_unbind:
451 unbind_from_irqhandler(vif->tx_irq, vif);
452 vif->tx_irq = 0;
f942dc25 453err_unmap:
7376419a 454 xenvif_unmap_frontend_rings(vif);
f942dc25 455err:
b103f358 456 module_put(THIS_MODULE);
f942dc25
IC
457 return err;
458}
459
48856286 460void xenvif_carrier_off(struct xenvif *vif)
f942dc25
IC
461{
462 struct net_device *dev = vif->dev;
48856286
IC
463
464 rtnl_lock();
465 netif_carrier_off(dev); /* discard queued packets */
466 if (netif_running(dev))
467 xenvif_down(vif);
468 rtnl_unlock();
48856286
IC
469}
470
471void xenvif_disconnect(struct xenvif *vif)
472{
473 if (netif_carrier_ok(vif->dev))
474 xenvif_carrier_off(vif);
f942dc25 475
67fa3660 476 if (vif->task) {
db739ef3 477 kthread_stop(vif->task);
67fa3660
PD
478 vif->task = NULL;
479 }
db739ef3 480
e1f00a69
WL
481 if (vif->tx_irq) {
482 if (vif->tx_irq == vif->rx_irq)
483 unbind_from_irqhandler(vif->tx_irq, vif);
484 else {
485 unbind_from_irqhandler(vif->tx_irq, vif);
486 unbind_from_irqhandler(vif->rx_irq, vif);
487 }
279f438e 488 vif->tx_irq = 0;
b103f358 489 }
f942dc25 490
279f438e
PD
491 xenvif_unmap_frontend_rings(vif);
492}
493
494void xenvif_free(struct xenvif *vif)
495{
b3f980bd
WL
496 netif_napi_del(&vif->napi);
497
f942dc25
IC
498 unregister_netdev(vif->dev);
499
ac3d5ac2 500 vfree(vif->grant_copy_op);
f942dc25 501 free_netdev(vif->dev);
b103f358 502
279f438e 503 module_put(THIS_MODULE);
f942dc25 504}