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21#include "common.h"
22#include <linux/vmalloc.h>
23#include <linux/rtnetlink.h>
24
25struct backend_info {
26 struct xenbus_device *dev;
27 struct xenvif *vif;
28
29
30
31
32 enum xenbus_state state;
33
34 enum xenbus_state frontend_state;
35 struct xenbus_watch hotplug_status_watch;
36 u8 have_hotplug_status_watch:1;
37
38 const char *hotplug_script;
39};
40
41static int connect_data_rings(struct backend_info *be,
42 struct xenvif_queue *queue);
43static void connect(struct backend_info *be);
44static int read_xenbus_vif_flags(struct backend_info *be);
45static int backend_create_xenvif(struct backend_info *be);
46static void unregister_hotplug_status_watch(struct backend_info *be);
47static void xen_unregister_watchers(struct xenvif *vif);
48static void set_backend_state(struct backend_info *be,
49 enum xenbus_state state);
50
51#ifdef CONFIG_DEBUG_FS
52struct dentry *xen_netback_dbg_root = NULL;
53
54static int xenvif_read_io_ring(struct seq_file *m, void *v)
55{
56 struct xenvif_queue *queue = m->private;
57 struct xen_netif_tx_back_ring *tx_ring = &queue->tx;
58 struct xen_netif_rx_back_ring *rx_ring = &queue->rx;
59 struct netdev_queue *dev_queue;
60
61 if (tx_ring->sring) {
62 struct xen_netif_tx_sring *sring = tx_ring->sring;
63
64 seq_printf(m, "Queue %d\nTX: nr_ents %u\n", queue->id,
65 tx_ring->nr_ents);
66 seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
67 sring->req_prod,
68 sring->req_prod - sring->rsp_prod,
69 tx_ring->req_cons,
70 tx_ring->req_cons - sring->rsp_prod,
71 sring->req_event,
72 sring->req_event - sring->rsp_prod);
73 seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n",
74 sring->rsp_prod,
75 tx_ring->rsp_prod_pvt,
76 tx_ring->rsp_prod_pvt - sring->rsp_prod,
77 sring->rsp_event,
78 sring->rsp_event - sring->rsp_prod);
79 seq_printf(m, "pending prod %u pending cons %u nr_pending_reqs %u\n",
80 queue->pending_prod,
81 queue->pending_cons,
82 nr_pending_reqs(queue));
83 seq_printf(m, "dealloc prod %u dealloc cons %u dealloc_queue %u\n\n",
84 queue->dealloc_prod,
85 queue->dealloc_cons,
86 queue->dealloc_prod - queue->dealloc_cons);
87 }
88
89 if (rx_ring->sring) {
90 struct xen_netif_rx_sring *sring = rx_ring->sring;
91
92 seq_printf(m, "RX: nr_ents %u\n", rx_ring->nr_ents);
93 seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
94 sring->req_prod,
95 sring->req_prod - sring->rsp_prod,
96 rx_ring->req_cons,
97 rx_ring->req_cons - sring->rsp_prod,
98 sring->req_event,
99 sring->req_event - sring->rsp_prod);
100 seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n\n",
101 sring->rsp_prod,
102 rx_ring->rsp_prod_pvt,
103 rx_ring->rsp_prod_pvt - sring->rsp_prod,
104 sring->rsp_event,
105 sring->rsp_event - sring->rsp_prod);
106 }
107
108 seq_printf(m, "NAPI state: %lx NAPI weight: %d TX queue len %u\n"
109 "Credit timer_pending: %d, credit: %lu, usec: %lu\n"
110 "remaining: %lu, expires: %lu, now: %lu\n",
111 queue->napi.state, queue->napi.weight,
112 skb_queue_len(&queue->tx_queue),
113 timer_pending(&queue->credit_timeout),
114 queue->credit_bytes,
115 queue->credit_usec,
116 queue->remaining_credit,
117 queue->credit_timeout.expires,
118 jiffies);
119
120 dev_queue = netdev_get_tx_queue(queue->vif->dev, queue->id);
121
122 seq_printf(m, "\nRx internal queue: len %u max %u pkts %u %s\n",
123 queue->rx_queue_len, queue->rx_queue_max,
124 skb_queue_len(&queue->rx_queue),
125 netif_tx_queue_stopped(dev_queue) ? "stopped" : "running");
126
127 return 0;
128}
129
130#define XENVIF_KICK_STR "kick"
131#define BUFFER_SIZE 32
132
133static ssize_t
134xenvif_write_io_ring(struct file *filp, const char __user *buf, size_t count,
135 loff_t *ppos)
136{
137 struct xenvif_queue *queue =
138 ((struct seq_file *)filp->private_data)->private;
139 int len;
140 char write[BUFFER_SIZE];
141
142
143 if (*ppos != 0)
144 return 0;
145 if (count >= sizeof(write))
146 return -ENOSPC;
147
148 len = simple_write_to_buffer(write,
149 sizeof(write) - 1,
150 ppos,
151 buf,
152 count);
153 if (len < 0)
154 return len;
155
156 write[len] = '\0';
157
158 if (!strncmp(write, XENVIF_KICK_STR, sizeof(XENVIF_KICK_STR) - 1))
159 xenvif_interrupt(0, (void *)queue);
160 else {
161 pr_warn("Unknown command to io_ring_q%d. Available: kick\n",
162 queue->id);
163 count = -EINVAL;
164 }
165 return count;
166}
167
168static int xenvif_dump_open(struct inode *inode, struct file *filp)
169{
170 int ret;
171 void *queue = NULL;
172
173 if (inode->i_private)
174 queue = inode->i_private;
175 ret = single_open(filp, xenvif_read_io_ring, queue);
176 filp->f_mode |= FMODE_PWRITE;
177 return ret;
178}
179
180static const struct file_operations xenvif_dbg_io_ring_ops_fops = {
181 .owner = THIS_MODULE,
182 .open = xenvif_dump_open,
183 .read = seq_read,
184 .llseek = seq_lseek,
185 .release = single_release,
186 .write = xenvif_write_io_ring,
187};
188
189static void xenvif_debugfs_addif(struct xenvif *vif)
190{
191 struct dentry *pfile;
192 int i;
193
194 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
195 return;
196
197 vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name,
198 xen_netback_dbg_root);
199 if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root)) {
200 for (i = 0; i < vif->num_queues; ++i) {
201 char filename[sizeof("io_ring_q") + 4];
202
203 snprintf(filename, sizeof(filename), "io_ring_q%d", i);
204 pfile = debugfs_create_file(filename,
205 S_IRUSR | S_IWUSR,
206 vif->xenvif_dbg_root,
207 &vif->queues[i],
208 &xenvif_dbg_io_ring_ops_fops);
209 if (IS_ERR_OR_NULL(pfile))
210 pr_warn("Creation of io_ring file returned %ld!\n",
211 PTR_ERR(pfile));
212 }
213 } else
214 netdev_warn(vif->dev,
215 "Creation of vif debugfs dir returned %ld!\n",
216 PTR_ERR(vif->xenvif_dbg_root));
217}
218
219static void xenvif_debugfs_delif(struct xenvif *vif)
220{
221 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
222 return;
223
224 if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root))
225 debugfs_remove_recursive(vif->xenvif_dbg_root);
226 vif->xenvif_dbg_root = NULL;
227}
228#endif
229
230static int netback_remove(struct xenbus_device *dev)
231{
232 struct backend_info *be = dev_get_drvdata(&dev->dev);
233
234 set_backend_state(be, XenbusStateClosed);
235
236 unregister_hotplug_status_watch(be);
237 if (be->vif) {
238 kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
239 xen_unregister_watchers(be->vif);
240 xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
241 xenvif_free(be->vif);
242 be->vif = NULL;
243 }
244 kfree(be->hotplug_script);
245 kfree(be);
246 dev_set_drvdata(&dev->dev, NULL);
247 return 0;
248}
249
250
251
252
253
254
255static int netback_probe(struct xenbus_device *dev,
256 const struct xenbus_device_id *id)
257{
258 const char *message;
259 struct xenbus_transaction xbt;
260 int err;
261 int sg;
262 const char *script;
263 struct backend_info *be = kzalloc(sizeof(struct backend_info),
264 GFP_KERNEL);
265 if (!be) {
266 xenbus_dev_fatal(dev, -ENOMEM,
267 "allocating backend structure");
268 return -ENOMEM;
269 }
270
271 be->dev = dev;
272 dev_set_drvdata(&dev->dev, be);
273
274 be->state = XenbusStateInitialising;
275 err = xenbus_switch_state(dev, XenbusStateInitialising);
276 if (err)
277 goto fail;
278
279 sg = 1;
280
281 do {
282 err = xenbus_transaction_start(&xbt);
283 if (err) {
284 xenbus_dev_fatal(dev, err, "starting transaction");
285 goto fail;
286 }
287
288 err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
289 if (err) {
290 message = "writing feature-sg";
291 goto abort_transaction;
292 }
293
294 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
295 "%d", sg);
296 if (err) {
297 message = "writing feature-gso-tcpv4";
298 goto abort_transaction;
299 }
300
301 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
302 "%d", sg);
303 if (err) {
304 message = "writing feature-gso-tcpv6";
305 goto abort_transaction;
306 }
307
308
309 err = xenbus_printf(xbt, dev->nodename,
310 "feature-ipv6-csum-offload",
311 "%d", 1);
312 if (err) {
313 message = "writing feature-ipv6-csum-offload";
314 goto abort_transaction;
315 }
316
317
318 err = xenbus_printf(xbt, dev->nodename,
319 "feature-rx-copy", "%d", 1);
320 if (err) {
321 message = "writing feature-rx-copy";
322 goto abort_transaction;
323 }
324
325
326
327
328
329 err = xenbus_printf(xbt, dev->nodename,
330 "feature-rx-flip", "%d", 0);
331 if (err) {
332 message = "writing feature-rx-flip";
333 goto abort_transaction;
334 }
335
336
337 err = xenbus_printf(xbt, dev->nodename,
338 "feature-multicast-control", "%d", 1);
339 if (err) {
340 message = "writing feature-multicast-control";
341 goto abort_transaction;
342 }
343
344 err = xenbus_printf(xbt, dev->nodename,
345 "feature-dynamic-multicast-control",
346 "%d", 1);
347 if (err) {
348 message = "writing feature-dynamic-multicast-control";
349 goto abort_transaction;
350 }
351
352 err = xenbus_transaction_end(xbt, 0);
353 } while (err == -EAGAIN);
354
355 if (err) {
356 xenbus_dev_fatal(dev, err, "completing transaction");
357 goto fail;
358 }
359
360
361
362
363
364 err = xenbus_printf(XBT_NIL, dev->nodename,
365 "feature-split-event-channels",
366 "%u", separate_tx_rx_irq);
367 if (err)
368 pr_debug("Error writing feature-split-event-channels\n");
369
370
371 err = xenbus_printf(XBT_NIL, dev->nodename,
372 "multi-queue-max-queues", "%u", xenvif_max_queues);
373 if (err)
374 pr_debug("Error writing multi-queue-max-queues\n");
375
376 err = xenbus_printf(XBT_NIL, dev->nodename,
377 "feature-ctrl-ring",
378 "%u", true);
379 if (err)
380 pr_debug("Error writing feature-ctrl-ring\n");
381
382 script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
383 if (IS_ERR(script)) {
384 err = PTR_ERR(script);
385 xenbus_dev_fatal(dev, err, "reading script");
386 goto fail;
387 }
388
389 be->hotplug_script = script;
390
391
392
393 err = backend_create_xenvif(be);
394 if (err)
395 goto fail;
396
397 return 0;
398
399abort_transaction:
400 xenbus_transaction_end(xbt, 1);
401 xenbus_dev_fatal(dev, err, "%s", message);
402fail:
403 pr_debug("failed\n");
404 netback_remove(dev);
405 return err;
406}
407
408
409
410
411
412
413
414static int netback_uevent(struct xenbus_device *xdev,
415 struct kobj_uevent_env *env)
416{
417 struct backend_info *be = dev_get_drvdata(&xdev->dev);
418
419 if (!be)
420 return 0;
421
422 if (add_uevent_var(env, "script=%s", be->hotplug_script))
423 return -ENOMEM;
424
425 if (!be->vif)
426 return 0;
427
428 return add_uevent_var(env, "vif=%s", be->vif->dev->name);
429}
430
431
432static int backend_create_xenvif(struct backend_info *be)
433{
434 int err;
435 long handle;
436 struct xenbus_device *dev = be->dev;
437 struct xenvif *vif;
438
439 if (be->vif != NULL)
440 return 0;
441
442 err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
443 if (err != 1) {
444 xenbus_dev_fatal(dev, err, "reading handle");
445 return (err < 0) ? err : -EINVAL;
446 }
447
448 vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
449 if (IS_ERR(vif)) {
450 err = PTR_ERR(vif);
451 xenbus_dev_fatal(dev, err, "creating interface");
452 return err;
453 }
454 be->vif = vif;
455
456 kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
457 return 0;
458}
459
460static void backend_disconnect(struct backend_info *be)
461{
462 if (be->vif) {
463 xen_unregister_watchers(be->vif);
464#ifdef CONFIG_DEBUG_FS
465 xenvif_debugfs_delif(be->vif);
466#endif
467 xenvif_disconnect_data(be->vif);
468 xenvif_disconnect_ctrl(be->vif);
469 }
470}
471
472static void backend_connect(struct backend_info *be)
473{
474 if (be->vif)
475 connect(be);
476}
477
478static inline void backend_switch_state(struct backend_info *be,
479 enum xenbus_state state)
480{
481 struct xenbus_device *dev = be->dev;
482
483 pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
484 be->state = state;
485
486
487
488
489 if (!be->have_hotplug_status_watch)
490 xenbus_switch_state(dev, state);
491}
492
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512
513static void set_backend_state(struct backend_info *be,
514 enum xenbus_state state)
515{
516 while (be->state != state) {
517 switch (be->state) {
518 case XenbusStateInitialising:
519 switch (state) {
520 case XenbusStateInitWait:
521 case XenbusStateConnected:
522 case XenbusStateClosing:
523 backend_switch_state(be, XenbusStateInitWait);
524 break;
525 case XenbusStateClosed:
526 backend_switch_state(be, XenbusStateClosed);
527 break;
528 default:
529 BUG();
530 }
531 break;
532 case XenbusStateClosed:
533 switch (state) {
534 case XenbusStateInitWait:
535 case XenbusStateConnected:
536 backend_switch_state(be, XenbusStateInitWait);
537 break;
538 case XenbusStateClosing:
539 backend_switch_state(be, XenbusStateClosing);
540 break;
541 default:
542 BUG();
543 }
544 break;
545 case XenbusStateInitWait:
546 switch (state) {
547 case XenbusStateConnected:
548 backend_connect(be);
549 backend_switch_state(be, XenbusStateConnected);
550 break;
551 case XenbusStateClosing:
552 case XenbusStateClosed:
553 backend_switch_state(be, XenbusStateClosing);
554 break;
555 default:
556 BUG();
557 }
558 break;
559 case XenbusStateConnected:
560 switch (state) {
561 case XenbusStateInitWait:
562 case XenbusStateClosing:
563 case XenbusStateClosed:
564 backend_disconnect(be);
565 backend_switch_state(be, XenbusStateClosing);
566 break;
567 default:
568 BUG();
569 }
570 break;
571 case XenbusStateClosing:
572 switch (state) {
573 case XenbusStateInitWait:
574 case XenbusStateConnected:
575 case XenbusStateClosed:
576 backend_switch_state(be, XenbusStateClosed);
577 break;
578 default:
579 BUG();
580 }
581 break;
582 default:
583 BUG();
584 }
585 }
586}
587
588
589
590
591static void frontend_changed(struct xenbus_device *dev,
592 enum xenbus_state frontend_state)
593{
594 struct backend_info *be = dev_get_drvdata(&dev->dev);
595
596 pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
597
598 be->frontend_state = frontend_state;
599
600 switch (frontend_state) {
601 case XenbusStateInitialising:
602 set_backend_state(be, XenbusStateInitWait);
603 break;
604
605 case XenbusStateInitialised:
606 break;
607
608 case XenbusStateConnected:
609 set_backend_state(be, XenbusStateConnected);
610 break;
611
612 case XenbusStateClosing:
613 set_backend_state(be, XenbusStateClosing);
614 break;
615
616 case XenbusStateClosed:
617 set_backend_state(be, XenbusStateClosed);
618 if (xenbus_dev_is_online(dev))
619 break;
620
621 case XenbusStateUnknown:
622 set_backend_state(be, XenbusStateClosed);
623 device_unregister(&dev->dev);
624 break;
625
626 default:
627 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
628 frontend_state);
629 break;
630 }
631}
632
633
634static void xen_net_read_rate(struct xenbus_device *dev,
635 unsigned long *bytes, unsigned long *usec)
636{
637 char *s, *e;
638 unsigned long b, u;
639 char *ratestr;
640
641
642 *bytes = ~0UL;
643 *usec = 0;
644
645 ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
646 if (IS_ERR(ratestr))
647 return;
648
649 s = ratestr;
650 b = simple_strtoul(s, &e, 10);
651 if ((s == e) || (*e != ','))
652 goto fail;
653
654 s = e + 1;
655 u = simple_strtoul(s, &e, 10);
656 if ((s == e) || (*e != '\0'))
657 goto fail;
658
659 *bytes = b;
660 *usec = u;
661
662 kfree(ratestr);
663 return;
664
665 fail:
666 pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
667 kfree(ratestr);
668}
669
670static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
671{
672 char *s, *e, *macstr;
673 int i;
674
675 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
676 if (IS_ERR(macstr))
677 return PTR_ERR(macstr);
678
679 for (i = 0; i < ETH_ALEN; i++) {
680 mac[i] = simple_strtoul(s, &e, 16);
681 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
682 kfree(macstr);
683 return -ENOENT;
684 }
685 s = e+1;
686 }
687
688 kfree(macstr);
689 return 0;
690}
691
692static void xen_net_rate_changed(struct xenbus_watch *watch,
693 const char **vec, unsigned int len)
694{
695 struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
696 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
697 unsigned long credit_bytes;
698 unsigned long credit_usec;
699 unsigned int queue_index;
700
701 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
702 for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
703 struct xenvif_queue *queue = &vif->queues[queue_index];
704
705 queue->credit_bytes = credit_bytes;
706 queue->credit_usec = credit_usec;
707 if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
708 queue->remaining_credit > queue->credit_bytes) {
709 queue->remaining_credit = queue->credit_bytes;
710 }
711 }
712}
713
714static int xen_register_credit_watch(struct xenbus_device *dev,
715 struct xenvif *vif)
716{
717 int err = 0;
718 char *node;
719 unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
720
721 if (vif->credit_watch.node)
722 return -EADDRINUSE;
723
724 node = kmalloc(maxlen, GFP_KERNEL);
725 if (!node)
726 return -ENOMEM;
727 snprintf(node, maxlen, "%s/rate", dev->nodename);
728 vif->credit_watch.node = node;
729 vif->credit_watch.callback = xen_net_rate_changed;
730 err = register_xenbus_watch(&vif->credit_watch);
731 if (err) {
732 pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
733 kfree(node);
734 vif->credit_watch.node = NULL;
735 vif->credit_watch.callback = NULL;
736 }
737 return err;
738}
739
740static void xen_unregister_credit_watch(struct xenvif *vif)
741{
742 if (vif->credit_watch.node) {
743 unregister_xenbus_watch(&vif->credit_watch);
744 kfree(vif->credit_watch.node);
745 vif->credit_watch.node = NULL;
746 }
747}
748
749static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
750 const char **vec, unsigned int len)
751{
752 struct xenvif *vif = container_of(watch, struct xenvif,
753 mcast_ctrl_watch);
754 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
755 int val;
756
757 if (xenbus_scanf(XBT_NIL, dev->otherend,
758 "request-multicast-control", "%d", &val) < 0)
759 val = 0;
760 vif->multicast_control = !!val;
761}
762
763static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
764 struct xenvif *vif)
765{
766 int err = 0;
767 char *node;
768 unsigned maxlen = strlen(dev->otherend) +
769 sizeof("/request-multicast-control");
770
771 if (vif->mcast_ctrl_watch.node) {
772 pr_err_ratelimited("Watch is already registered\n");
773 return -EADDRINUSE;
774 }
775
776 node = kmalloc(maxlen, GFP_KERNEL);
777 if (!node) {
778 pr_err("Failed to allocate memory for watch\n");
779 return -ENOMEM;
780 }
781 snprintf(node, maxlen, "%s/request-multicast-control",
782 dev->otherend);
783 vif->mcast_ctrl_watch.node = node;
784 vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
785 err = register_xenbus_watch(&vif->mcast_ctrl_watch);
786 if (err) {
787 pr_err("Failed to set watcher %s\n",
788 vif->mcast_ctrl_watch.node);
789 kfree(node);
790 vif->mcast_ctrl_watch.node = NULL;
791 vif->mcast_ctrl_watch.callback = NULL;
792 }
793 return err;
794}
795
796static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
797{
798 if (vif->mcast_ctrl_watch.node) {
799 unregister_xenbus_watch(&vif->mcast_ctrl_watch);
800 kfree(vif->mcast_ctrl_watch.node);
801 vif->mcast_ctrl_watch.node = NULL;
802 }
803}
804
805static void xen_register_watchers(struct xenbus_device *dev,
806 struct xenvif *vif)
807{
808 xen_register_credit_watch(dev, vif);
809 xen_register_mcast_ctrl_watch(dev, vif);
810}
811
812static void xen_unregister_watchers(struct xenvif *vif)
813{
814 xen_unregister_mcast_ctrl_watch(vif);
815 xen_unregister_credit_watch(vif);
816}
817
818static void unregister_hotplug_status_watch(struct backend_info *be)
819{
820 if (be->have_hotplug_status_watch) {
821 unregister_xenbus_watch(&be->hotplug_status_watch);
822 kfree(be->hotplug_status_watch.node);
823 }
824 be->have_hotplug_status_watch = 0;
825}
826
827static void hotplug_status_changed(struct xenbus_watch *watch,
828 const char **vec,
829 unsigned int vec_size)
830{
831 struct backend_info *be = container_of(watch,
832 struct backend_info,
833 hotplug_status_watch);
834 char *str;
835 unsigned int len;
836
837 str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
838 if (IS_ERR(str))
839 return;
840 if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
841
842 xenbus_switch_state(be->dev, be->state);
843
844
845 unregister_hotplug_status_watch(be);
846 }
847 kfree(str);
848}
849
850static int connect_ctrl_ring(struct backend_info *be)
851{
852 struct xenbus_device *dev = be->dev;
853 struct xenvif *vif = be->vif;
854 unsigned int val;
855 grant_ref_t ring_ref;
856 unsigned int evtchn;
857 int err;
858
859 err = xenbus_gather(XBT_NIL, dev->otherend,
860 "ctrl-ring-ref", "%u", &val, NULL);
861 if (err)
862 goto done;
863
864 ring_ref = val;
865
866 err = xenbus_gather(XBT_NIL, dev->otherend,
867 "event-channel-ctrl", "%u", &val, NULL);
868 if (err) {
869 xenbus_dev_fatal(dev, err,
870 "reading %s/event-channel-ctrl",
871 dev->otherend);
872 goto fail;
873 }
874
875 evtchn = val;
876
877 err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
878 if (err) {
879 xenbus_dev_fatal(dev, err,
880 "mapping shared-frame %u port %u",
881 ring_ref, evtchn);
882 goto fail;
883 }
884
885done:
886 return 0;
887
888fail:
889 return err;
890}
891
892static void connect(struct backend_info *be)
893{
894 int err;
895 struct xenbus_device *dev = be->dev;
896 unsigned long credit_bytes, credit_usec;
897 unsigned int queue_index;
898 unsigned int requested_num_queues;
899 struct xenvif_queue *queue;
900
901
902
903
904 err = xenbus_scanf(XBT_NIL, dev->otherend,
905 "multi-queue-num-queues",
906 "%u", &requested_num_queues);
907 if (err < 0) {
908 requested_num_queues = 1;
909 } else if (requested_num_queues > xenvif_max_queues) {
910
911 xenbus_dev_fatal(dev, err,
912 "guest requested %u queues, exceeding the maximum of %u.",
913 requested_num_queues, xenvif_max_queues);
914 return;
915 }
916
917 err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
918 if (err) {
919 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
920 return;
921 }
922
923 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
924 xen_unregister_watchers(be->vif);
925 xen_register_watchers(dev, be->vif);
926 read_xenbus_vif_flags(be);
927
928 err = connect_ctrl_ring(be);
929 if (err) {
930 xenbus_dev_fatal(dev, err, "connecting control ring");
931 return;
932 }
933
934
935 be->vif->queues = vzalloc(requested_num_queues *
936 sizeof(struct xenvif_queue));
937 if (!be->vif->queues) {
938 xenbus_dev_fatal(dev, -ENOMEM,
939 "allocating queues");
940 return;
941 }
942
943 be->vif->num_queues = requested_num_queues;
944 be->vif->stalled_queues = requested_num_queues;
945
946 for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
947 queue = &be->vif->queues[queue_index];
948 queue->vif = be->vif;
949 queue->id = queue_index;
950 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
951 be->vif->dev->name, queue->id);
952
953 err = xenvif_init_queue(queue);
954 if (err) {
955
956
957
958
959
960
961 be->vif->num_queues = queue_index;
962 goto err;
963 }
964
965 queue->credit_bytes = credit_bytes;
966 queue->remaining_credit = credit_bytes;
967 queue->credit_usec = credit_usec;
968
969 err = connect_data_rings(be, queue);
970 if (err) {
971
972
973
974
975
976 xenvif_deinit_queue(queue);
977 be->vif->num_queues = queue_index;
978 goto err;
979 }
980 }
981
982#ifdef CONFIG_DEBUG_FS
983 xenvif_debugfs_addif(be->vif);
984#endif
985
986
987
988
989 rtnl_lock();
990 netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
991 netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
992 rtnl_unlock();
993
994 xenvif_carrier_on(be->vif);
995
996 unregister_hotplug_status_watch(be);
997 err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
998 hotplug_status_changed,
999 "%s/%s", dev->nodename, "hotplug-status");
1000 if (!err)
1001 be->have_hotplug_status_watch = 1;
1002
1003 netif_tx_wake_all_queues(be->vif->dev);
1004
1005 return;
1006
1007err:
1008 if (be->vif->num_queues > 0)
1009 xenvif_disconnect_data(be->vif);
1010 vfree(be->vif->queues);
1011 be->vif->queues = NULL;
1012 be->vif->num_queues = 0;
1013 xenvif_disconnect_ctrl(be->vif);
1014 return;
1015}
1016
1017
1018static int connect_data_rings(struct backend_info *be,
1019 struct xenvif_queue *queue)
1020{
1021 struct xenbus_device *dev = be->dev;
1022 unsigned int num_queues = queue->vif->num_queues;
1023 unsigned long tx_ring_ref, rx_ring_ref;
1024 unsigned int tx_evtchn, rx_evtchn;
1025 int err;
1026 char *xspath;
1027 size_t xspathsize;
1028 const size_t xenstore_path_ext_size = 11;
1029
1030
1031
1032
1033
1034
1035
1036 if (num_queues == 1) {
1037 xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
1038 if (!xspath) {
1039 xenbus_dev_fatal(dev, -ENOMEM,
1040 "reading ring references");
1041 return -ENOMEM;
1042 }
1043 strcpy(xspath, dev->otherend);
1044 } else {
1045 xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
1046 xspath = kzalloc(xspathsize, GFP_KERNEL);
1047 if (!xspath) {
1048 xenbus_dev_fatal(dev, -ENOMEM,
1049 "reading ring references");
1050 return -ENOMEM;
1051 }
1052 snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
1053 queue->id);
1054 }
1055
1056 err = xenbus_gather(XBT_NIL, xspath,
1057 "tx-ring-ref", "%lu", &tx_ring_ref,
1058 "rx-ring-ref", "%lu", &rx_ring_ref, NULL);
1059 if (err) {
1060 xenbus_dev_fatal(dev, err,
1061 "reading %s/ring-ref",
1062 xspath);
1063 goto err;
1064 }
1065
1066
1067 err = xenbus_gather(XBT_NIL, xspath,
1068 "event-channel-tx", "%u", &tx_evtchn,
1069 "event-channel-rx", "%u", &rx_evtchn, NULL);
1070 if (err < 0) {
1071 err = xenbus_scanf(XBT_NIL, xspath,
1072 "event-channel", "%u", &tx_evtchn);
1073 if (err < 0) {
1074 xenbus_dev_fatal(dev, err,
1075 "reading %s/event-channel(-tx/rx)",
1076 xspath);
1077 goto err;
1078 }
1079 rx_evtchn = tx_evtchn;
1080 }
1081
1082
1083 err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
1084 tx_evtchn, rx_evtchn);
1085 if (err) {
1086 xenbus_dev_fatal(dev, err,
1087 "mapping shared-frames %lu/%lu port tx %u rx %u",
1088 tx_ring_ref, rx_ring_ref,
1089 tx_evtchn, rx_evtchn);
1090 goto err;
1091 }
1092
1093 err = 0;
1094err:
1095 kfree(xspath);
1096 return err;
1097}
1098
1099static int read_xenbus_vif_flags(struct backend_info *be)
1100{
1101 struct xenvif *vif = be->vif;
1102 struct xenbus_device *dev = be->dev;
1103 unsigned int rx_copy;
1104 int err, val;
1105
1106 err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
1107 &rx_copy);
1108 if (err == -ENOENT) {
1109 err = 0;
1110 rx_copy = 0;
1111 }
1112 if (err < 0) {
1113 xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
1114 dev->otherend);
1115 return err;
1116 }
1117 if (!rx_copy)
1118 return -EOPNOTSUPP;
1119
1120 if (xenbus_scanf(XBT_NIL, dev->otherend,
1121 "feature-rx-notify", "%d", &val) < 0)
1122 val = 0;
1123 if (!val) {
1124
1125
1126
1127
1128 be->vif->drain_timeout = msecs_to_jiffies(30);
1129 be->vif->stall_timeout = 0;
1130 }
1131
1132 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg",
1133 "%d", &val) < 0)
1134 val = 0;
1135 vif->can_sg = !!val;
1136
1137 vif->gso_mask = 0;
1138 vif->gso_prefix_mask = 0;
1139
1140 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4",
1141 "%d", &val) < 0)
1142 val = 0;
1143 if (val)
1144 vif->gso_mask |= GSO_BIT(TCPV4);
1145
1146 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4-prefix",
1147 "%d", &val) < 0)
1148 val = 0;
1149 if (val)
1150 vif->gso_prefix_mask |= GSO_BIT(TCPV4);
1151
1152 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6",
1153 "%d", &val) < 0)
1154 val = 0;
1155 if (val)
1156 vif->gso_mask |= GSO_BIT(TCPV6);
1157
1158 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6-prefix",
1159 "%d", &val) < 0)
1160 val = 0;
1161 if (val)
1162 vif->gso_prefix_mask |= GSO_BIT(TCPV6);
1163
1164 if (vif->gso_mask & vif->gso_prefix_mask) {
1165 xenbus_dev_fatal(dev, err,
1166 "%s: gso and gso prefix flags are not "
1167 "mutually exclusive",
1168 dev->otherend);
1169 return -EOPNOTSUPP;
1170 }
1171
1172 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload",
1173 "%d", &val) < 0)
1174 val = 0;
1175 vif->ip_csum = !val;
1176
1177 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-ipv6-csum-offload",
1178 "%d", &val) < 0)
1179 val = 0;
1180 vif->ipv6_csum = !!val;
1181
1182 return 0;
1183}
1184
1185static const struct xenbus_device_id netback_ids[] = {
1186 { "vif" },
1187 { "" }
1188};
1189
1190static struct xenbus_driver netback_driver = {
1191 .ids = netback_ids,
1192 .probe = netback_probe,
1193 .remove = netback_remove,
1194 .uevent = netback_uevent,
1195 .otherend_changed = frontend_changed,
1196};
1197
1198int xenvif_xenbus_init(void)
1199{
1200 return xenbus_register_backend(&netback_driver);
1201}
1202
1203void xenvif_xenbus_fini(void)
1204{
1205 return xenbus_unregister_driver(&netback_driver);
1206}
1207
