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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_io_ring_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_io_ring_open,
183 .read = seq_read,
184 .llseek = seq_lseek,
185 .release = single_release,
186 .write = xenvif_write_io_ring,
187};
188
189static int xenvif_read_ctrl(struct seq_file *m, void *v)
190{
191 struct xenvif *vif = m->private;
192
193 xenvif_dump_hash_info(vif, m);
194
195 return 0;
196}
197
198static int xenvif_ctrl_open(struct inode *inode, struct file *filp)
199{
200 return single_open(filp, xenvif_read_ctrl, inode->i_private);
201}
202
203static const struct file_operations xenvif_dbg_ctrl_ops_fops = {
204 .owner = THIS_MODULE,
205 .open = xenvif_ctrl_open,
206 .read = seq_read,
207 .llseek = seq_lseek,
208 .release = single_release,
209};
210
211static void xenvif_debugfs_addif(struct xenvif *vif)
212{
213 struct dentry *pfile;
214 int i;
215
216 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
217 return;
218
219 vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name,
220 xen_netback_dbg_root);
221 if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root)) {
222 for (i = 0; i < vif->num_queues; ++i) {
223 char filename[sizeof("io_ring_q") + 4];
224
225 snprintf(filename, sizeof(filename), "io_ring_q%d", i);
226 pfile = debugfs_create_file(filename,
227 S_IRUSR | S_IWUSR,
228 vif->xenvif_dbg_root,
229 &vif->queues[i],
230 &xenvif_dbg_io_ring_ops_fops);
231 if (IS_ERR_OR_NULL(pfile))
232 pr_warn("Creation of io_ring file returned %ld!\n",
233 PTR_ERR(pfile));
234 }
235
236 if (vif->ctrl_irq) {
237 pfile = debugfs_create_file("ctrl",
238 S_IRUSR,
239 vif->xenvif_dbg_root,
240 vif,
241 &xenvif_dbg_ctrl_ops_fops);
242 if (IS_ERR_OR_NULL(pfile))
243 pr_warn("Creation of ctrl file returned %ld!\n",
244 PTR_ERR(pfile));
245 }
246 } else
247 netdev_warn(vif->dev,
248 "Creation of vif debugfs dir returned %ld!\n",
249 PTR_ERR(vif->xenvif_dbg_root));
250}
251
252static void xenvif_debugfs_delif(struct xenvif *vif)
253{
254 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
255 return;
256
257 if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root))
258 debugfs_remove_recursive(vif->xenvif_dbg_root);
259 vif->xenvif_dbg_root = NULL;
260}
261#endif
262
263static int netback_remove(struct xenbus_device *dev)
264{
265 struct backend_info *be = dev_get_drvdata(&dev->dev);
266
267 set_backend_state(be, XenbusStateClosed);
268
269 unregister_hotplug_status_watch(be);
270 if (be->vif) {
271 kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
272 xen_unregister_watchers(be->vif);
273 xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
274 xenvif_free(be->vif);
275 be->vif = NULL;
276 }
277 kfree(be->hotplug_script);
278 kfree(be);
279 dev_set_drvdata(&dev->dev, NULL);
280 return 0;
281}
282
283
284
285
286
287
288static int netback_probe(struct xenbus_device *dev,
289 const struct xenbus_device_id *id)
290{
291 const char *message;
292 struct xenbus_transaction xbt;
293 int err;
294 int sg;
295 const char *script;
296 struct backend_info *be = kzalloc(sizeof(struct backend_info),
297 GFP_KERNEL);
298 if (!be) {
299 xenbus_dev_fatal(dev, -ENOMEM,
300 "allocating backend structure");
301 return -ENOMEM;
302 }
303
304 be->dev = dev;
305 dev_set_drvdata(&dev->dev, be);
306
307 be->state = XenbusStateInitialising;
308 err = xenbus_switch_state(dev, XenbusStateInitialising);
309 if (err)
310 goto fail;
311
312 sg = 1;
313
314 do {
315 err = xenbus_transaction_start(&xbt);
316 if (err) {
317 xenbus_dev_fatal(dev, err, "starting transaction");
318 goto fail;
319 }
320
321 err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
322 if (err) {
323 message = "writing feature-sg";
324 goto abort_transaction;
325 }
326
327 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
328 "%d", sg);
329 if (err) {
330 message = "writing feature-gso-tcpv4";
331 goto abort_transaction;
332 }
333
334 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
335 "%d", sg);
336 if (err) {
337 message = "writing feature-gso-tcpv6";
338 goto abort_transaction;
339 }
340
341
342 err = xenbus_printf(xbt, dev->nodename,
343 "feature-ipv6-csum-offload",
344 "%d", 1);
345 if (err) {
346 message = "writing feature-ipv6-csum-offload";
347 goto abort_transaction;
348 }
349
350
351 err = xenbus_printf(xbt, dev->nodename,
352 "feature-rx-copy", "%d", 1);
353 if (err) {
354 message = "writing feature-rx-copy";
355 goto abort_transaction;
356 }
357
358
359
360
361
362 err = xenbus_printf(xbt, dev->nodename,
363 "feature-rx-flip", "%d", 0);
364 if (err) {
365 message = "writing feature-rx-flip";
366 goto abort_transaction;
367 }
368
369
370 err = xenbus_printf(xbt, dev->nodename,
371 "feature-multicast-control", "%d", 1);
372 if (err) {
373 message = "writing feature-multicast-control";
374 goto abort_transaction;
375 }
376
377 err = xenbus_printf(xbt, dev->nodename,
378 "feature-dynamic-multicast-control",
379 "%d", 1);
380 if (err) {
381 message = "writing feature-dynamic-multicast-control";
382 goto abort_transaction;
383 }
384
385 err = xenbus_transaction_end(xbt, 0);
386 } while (err == -EAGAIN);
387
388 if (err) {
389 xenbus_dev_fatal(dev, err, "completing transaction");
390 goto fail;
391 }
392
393
394
395
396
397 err = xenbus_printf(XBT_NIL, dev->nodename,
398 "feature-split-event-channels",
399 "%u", separate_tx_rx_irq);
400 if (err)
401 pr_debug("Error writing feature-split-event-channels\n");
402
403
404 err = xenbus_printf(XBT_NIL, dev->nodename,
405 "multi-queue-max-queues", "%u", xenvif_max_queues);
406 if (err)
407 pr_debug("Error writing multi-queue-max-queues\n");
408
409 err = xenbus_printf(XBT_NIL, dev->nodename,
410 "feature-ctrl-ring",
411 "%u", true);
412 if (err)
413 pr_debug("Error writing feature-ctrl-ring\n");
414
415 script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
416 if (IS_ERR(script)) {
417 err = PTR_ERR(script);
418 xenbus_dev_fatal(dev, err, "reading script");
419 goto fail;
420 }
421
422 be->hotplug_script = script;
423
424
425
426 err = backend_create_xenvif(be);
427 if (err)
428 goto fail;
429
430 return 0;
431
432abort_transaction:
433 xenbus_transaction_end(xbt, 1);
434 xenbus_dev_fatal(dev, err, "%s", message);
435fail:
436 pr_debug("failed\n");
437 netback_remove(dev);
438 return err;
439}
440
441
442
443
444
445
446
447static int netback_uevent(struct xenbus_device *xdev,
448 struct kobj_uevent_env *env)
449{
450 struct backend_info *be = dev_get_drvdata(&xdev->dev);
451
452 if (!be)
453 return 0;
454
455 if (add_uevent_var(env, "script=%s", be->hotplug_script))
456 return -ENOMEM;
457
458 if (!be->vif)
459 return 0;
460
461 return add_uevent_var(env, "vif=%s", be->vif->dev->name);
462}
463
464
465static int backend_create_xenvif(struct backend_info *be)
466{
467 int err;
468 long handle;
469 struct xenbus_device *dev = be->dev;
470 struct xenvif *vif;
471
472 if (be->vif != NULL)
473 return 0;
474
475 err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
476 if (err != 1) {
477 xenbus_dev_fatal(dev, err, "reading handle");
478 return (err < 0) ? err : -EINVAL;
479 }
480
481 vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
482 if (IS_ERR(vif)) {
483 err = PTR_ERR(vif);
484 xenbus_dev_fatal(dev, err, "creating interface");
485 return err;
486 }
487 be->vif = vif;
488
489 kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
490 return 0;
491}
492
493static void backend_disconnect(struct backend_info *be)
494{
495 struct xenvif *vif = be->vif;
496
497 if (vif) {
498 unsigned int num_queues = vif->num_queues;
499 unsigned int queue_index;
500
501 xen_unregister_watchers(vif);
502#ifdef CONFIG_DEBUG_FS
503 xenvif_debugfs_delif(vif);
504#endif
505 xenvif_disconnect_data(vif);
506
507
508
509
510 vif->num_queues = 0;
511 synchronize_net();
512
513 for (queue_index = 0; queue_index < num_queues; ++queue_index)
514 xenvif_deinit_queue(&vif->queues[queue_index]);
515
516 vfree(vif->queues);
517 vif->queues = NULL;
518
519 xenvif_disconnect_ctrl(vif);
520 }
521}
522
523static void backend_connect(struct backend_info *be)
524{
525 if (be->vif)
526 connect(be);
527}
528
529static inline void backend_switch_state(struct backend_info *be,
530 enum xenbus_state state)
531{
532 struct xenbus_device *dev = be->dev;
533
534 pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
535 be->state = state;
536
537
538
539
540 if (!be->have_hotplug_status_watch)
541 xenbus_switch_state(dev, state);
542}
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563
564static void set_backend_state(struct backend_info *be,
565 enum xenbus_state state)
566{
567 while (be->state != state) {
568 switch (be->state) {
569 case XenbusStateInitialising:
570 switch (state) {
571 case XenbusStateInitWait:
572 case XenbusStateConnected:
573 case XenbusStateClosing:
574 backend_switch_state(be, XenbusStateInitWait);
575 break;
576 case XenbusStateClosed:
577 backend_switch_state(be, XenbusStateClosed);
578 break;
579 default:
580 BUG();
581 }
582 break;
583 case XenbusStateClosed:
584 switch (state) {
585 case XenbusStateInitWait:
586 case XenbusStateConnected:
587 backend_switch_state(be, XenbusStateInitWait);
588 break;
589 case XenbusStateClosing:
590 backend_switch_state(be, XenbusStateClosing);
591 break;
592 default:
593 BUG();
594 }
595 break;
596 case XenbusStateInitWait:
597 switch (state) {
598 case XenbusStateConnected:
599 backend_connect(be);
600 backend_switch_state(be, XenbusStateConnected);
601 break;
602 case XenbusStateClosing:
603 case XenbusStateClosed:
604 backend_switch_state(be, XenbusStateClosing);
605 break;
606 default:
607 BUG();
608 }
609 break;
610 case XenbusStateConnected:
611 switch (state) {
612 case XenbusStateInitWait:
613 case XenbusStateClosing:
614 case XenbusStateClosed:
615 backend_disconnect(be);
616 backend_switch_state(be, XenbusStateClosing);
617 break;
618 default:
619 BUG();
620 }
621 break;
622 case XenbusStateClosing:
623 switch (state) {
624 case XenbusStateInitWait:
625 case XenbusStateConnected:
626 case XenbusStateClosed:
627 backend_switch_state(be, XenbusStateClosed);
628 break;
629 default:
630 BUG();
631 }
632 break;
633 default:
634 BUG();
635 }
636 }
637}
638
639
640
641
642static void frontend_changed(struct xenbus_device *dev,
643 enum xenbus_state frontend_state)
644{
645 struct backend_info *be = dev_get_drvdata(&dev->dev);
646
647 pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
648
649 be->frontend_state = frontend_state;
650
651 switch (frontend_state) {
652 case XenbusStateInitialising:
653 set_backend_state(be, XenbusStateInitWait);
654 break;
655
656 case XenbusStateInitialised:
657 break;
658
659 case XenbusStateConnected:
660 set_backend_state(be, XenbusStateConnected);
661 break;
662
663 case XenbusStateClosing:
664 set_backend_state(be, XenbusStateClosing);
665 break;
666
667 case XenbusStateClosed:
668 set_backend_state(be, XenbusStateClosed);
669 if (xenbus_dev_is_online(dev))
670 break;
671
672 case XenbusStateUnknown:
673 set_backend_state(be, XenbusStateClosed);
674 device_unregister(&dev->dev);
675 break;
676
677 default:
678 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
679 frontend_state);
680 break;
681 }
682}
683
684
685static void xen_net_read_rate(struct xenbus_device *dev,
686 unsigned long *bytes, unsigned long *usec)
687{
688 char *s, *e;
689 unsigned long b, u;
690 char *ratestr;
691
692
693 *bytes = ~0UL;
694 *usec = 0;
695
696 ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
697 if (IS_ERR(ratestr))
698 return;
699
700 s = ratestr;
701 b = simple_strtoul(s, &e, 10);
702 if ((s == e) || (*e != ','))
703 goto fail;
704
705 s = e + 1;
706 u = simple_strtoul(s, &e, 10);
707 if ((s == e) || (*e != '\0'))
708 goto fail;
709
710 *bytes = b;
711 *usec = u;
712
713 kfree(ratestr);
714 return;
715
716 fail:
717 pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
718 kfree(ratestr);
719}
720
721static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
722{
723 char *s, *e, *macstr;
724 int i;
725
726 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
727 if (IS_ERR(macstr))
728 return PTR_ERR(macstr);
729
730 for (i = 0; i < ETH_ALEN; i++) {
731 mac[i] = simple_strtoul(s, &e, 16);
732 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
733 kfree(macstr);
734 return -ENOENT;
735 }
736 s = e+1;
737 }
738
739 kfree(macstr);
740 return 0;
741}
742
743static void xen_net_rate_changed(struct xenbus_watch *watch,
744 const char *path, const char *token)
745{
746 struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
747 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
748 unsigned long credit_bytes;
749 unsigned long credit_usec;
750 unsigned int queue_index;
751
752 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
753 for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
754 struct xenvif_queue *queue = &vif->queues[queue_index];
755
756 queue->credit_bytes = credit_bytes;
757 queue->credit_usec = credit_usec;
758 if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
759 queue->remaining_credit > queue->credit_bytes) {
760 queue->remaining_credit = queue->credit_bytes;
761 }
762 }
763}
764
765static int xen_register_credit_watch(struct xenbus_device *dev,
766 struct xenvif *vif)
767{
768 int err = 0;
769 char *node;
770 unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
771
772 if (vif->credit_watch.node)
773 return -EADDRINUSE;
774
775 node = kmalloc(maxlen, GFP_KERNEL);
776 if (!node)
777 return -ENOMEM;
778 snprintf(node, maxlen, "%s/rate", dev->nodename);
779 vif->credit_watch.node = node;
780 vif->credit_watch.callback = xen_net_rate_changed;
781 err = register_xenbus_watch(&vif->credit_watch);
782 if (err) {
783 pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
784 kfree(node);
785 vif->credit_watch.node = NULL;
786 vif->credit_watch.callback = NULL;
787 }
788 return err;
789}
790
791static void xen_unregister_credit_watch(struct xenvif *vif)
792{
793 if (vif->credit_watch.node) {
794 unregister_xenbus_watch(&vif->credit_watch);
795 kfree(vif->credit_watch.node);
796 vif->credit_watch.node = NULL;
797 }
798}
799
800static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
801 const char *path, const char *token)
802{
803 struct xenvif *vif = container_of(watch, struct xenvif,
804 mcast_ctrl_watch);
805 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
806
807 vif->multicast_control = !!xenbus_read_unsigned(dev->otherend,
808 "request-multicast-control", 0);
809}
810
811static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
812 struct xenvif *vif)
813{
814 int err = 0;
815 char *node;
816 unsigned maxlen = strlen(dev->otherend) +
817 sizeof("/request-multicast-control");
818
819 if (vif->mcast_ctrl_watch.node) {
820 pr_err_ratelimited("Watch is already registered\n");
821 return -EADDRINUSE;
822 }
823
824 node = kmalloc(maxlen, GFP_KERNEL);
825 if (!node) {
826 pr_err("Failed to allocate memory for watch\n");
827 return -ENOMEM;
828 }
829 snprintf(node, maxlen, "%s/request-multicast-control",
830 dev->otherend);
831 vif->mcast_ctrl_watch.node = node;
832 vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
833 err = register_xenbus_watch(&vif->mcast_ctrl_watch);
834 if (err) {
835 pr_err("Failed to set watcher %s\n",
836 vif->mcast_ctrl_watch.node);
837 kfree(node);
838 vif->mcast_ctrl_watch.node = NULL;
839 vif->mcast_ctrl_watch.callback = NULL;
840 }
841 return err;
842}
843
844static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
845{
846 if (vif->mcast_ctrl_watch.node) {
847 unregister_xenbus_watch(&vif->mcast_ctrl_watch);
848 kfree(vif->mcast_ctrl_watch.node);
849 vif->mcast_ctrl_watch.node = NULL;
850 }
851}
852
853static void xen_register_watchers(struct xenbus_device *dev,
854 struct xenvif *vif)
855{
856 xen_register_credit_watch(dev, vif);
857 xen_register_mcast_ctrl_watch(dev, vif);
858}
859
860static void xen_unregister_watchers(struct xenvif *vif)
861{
862 xen_unregister_mcast_ctrl_watch(vif);
863 xen_unregister_credit_watch(vif);
864}
865
866static void unregister_hotplug_status_watch(struct backend_info *be)
867{
868 if (be->have_hotplug_status_watch) {
869 unregister_xenbus_watch(&be->hotplug_status_watch);
870 kfree(be->hotplug_status_watch.node);
871 }
872 be->have_hotplug_status_watch = 0;
873}
874
875static void hotplug_status_changed(struct xenbus_watch *watch,
876 const char *path,
877 const char *token)
878{
879 struct backend_info *be = container_of(watch,
880 struct backend_info,
881 hotplug_status_watch);
882 char *str;
883 unsigned int len;
884
885 str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
886 if (IS_ERR(str))
887 return;
888 if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
889
890 xenbus_switch_state(be->dev, be->state);
891
892
893 unregister_hotplug_status_watch(be);
894 }
895 kfree(str);
896}
897
898static int connect_ctrl_ring(struct backend_info *be)
899{
900 struct xenbus_device *dev = be->dev;
901 struct xenvif *vif = be->vif;
902 unsigned int val;
903 grant_ref_t ring_ref;
904 unsigned int evtchn;
905 int err;
906
907 err = xenbus_scanf(XBT_NIL, dev->otherend,
908 "ctrl-ring-ref", "%u", &val);
909 if (err < 0)
910 goto done;
911
912 ring_ref = val;
913
914 err = xenbus_scanf(XBT_NIL, dev->otherend,
915 "event-channel-ctrl", "%u", &val);
916 if (err < 0) {
917 xenbus_dev_fatal(dev, err,
918 "reading %s/event-channel-ctrl",
919 dev->otherend);
920 goto fail;
921 }
922
923 evtchn = val;
924
925 err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
926 if (err) {
927 xenbus_dev_fatal(dev, err,
928 "mapping shared-frame %u port %u",
929 ring_ref, evtchn);
930 goto fail;
931 }
932
933done:
934 return 0;
935
936fail:
937 return err;
938}
939
940static void connect(struct backend_info *be)
941{
942 int err;
943 struct xenbus_device *dev = be->dev;
944 unsigned long credit_bytes, credit_usec;
945 unsigned int queue_index;
946 unsigned int requested_num_queues;
947 struct xenvif_queue *queue;
948
949
950
951
952 requested_num_queues = xenbus_read_unsigned(dev->otherend,
953 "multi-queue-num-queues", 1);
954 if (requested_num_queues > xenvif_max_queues) {
955
956 xenbus_dev_fatal(dev, -EINVAL,
957 "guest requested %u queues, exceeding the maximum of %u.",
958 requested_num_queues, xenvif_max_queues);
959 return;
960 }
961
962 err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
963 if (err) {
964 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
965 return;
966 }
967
968 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
969 xen_unregister_watchers(be->vif);
970 xen_register_watchers(dev, be->vif);
971 read_xenbus_vif_flags(be);
972
973 err = connect_ctrl_ring(be);
974 if (err) {
975 xenbus_dev_fatal(dev, err, "connecting control ring");
976 return;
977 }
978
979
980 be->vif->queues = vzalloc(requested_num_queues *
981 sizeof(struct xenvif_queue));
982 if (!be->vif->queues) {
983 xenbus_dev_fatal(dev, -ENOMEM,
984 "allocating queues");
985 return;
986 }
987
988 be->vif->num_queues = requested_num_queues;
989 be->vif->stalled_queues = requested_num_queues;
990
991 for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
992 queue = &be->vif->queues[queue_index];
993 queue->vif = be->vif;
994 queue->id = queue_index;
995 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
996 be->vif->dev->name, queue->id);
997
998 err = xenvif_init_queue(queue);
999 if (err) {
1000
1001
1002
1003
1004
1005
1006 be->vif->num_queues = queue_index;
1007 goto err;
1008 }
1009
1010 queue->credit_bytes = credit_bytes;
1011 queue->remaining_credit = credit_bytes;
1012 queue->credit_usec = credit_usec;
1013
1014 err = connect_data_rings(be, queue);
1015 if (err) {
1016
1017
1018
1019
1020
1021 xenvif_deinit_queue(queue);
1022 be->vif->num_queues = queue_index;
1023 goto err;
1024 }
1025 }
1026
1027#ifdef CONFIG_DEBUG_FS
1028 xenvif_debugfs_addif(be->vif);
1029#endif
1030
1031
1032
1033
1034 rtnl_lock();
1035 netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
1036 netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
1037 rtnl_unlock();
1038
1039 xenvif_carrier_on(be->vif);
1040
1041 unregister_hotplug_status_watch(be);
1042 err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
1043 hotplug_status_changed,
1044 "%s/%s", dev->nodename, "hotplug-status");
1045 if (!err)
1046 be->have_hotplug_status_watch = 1;
1047
1048 netif_tx_wake_all_queues(be->vif->dev);
1049
1050 return;
1051
1052err:
1053 if (be->vif->num_queues > 0)
1054 xenvif_disconnect_data(be->vif);
1055 for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
1056 xenvif_deinit_queue(&be->vif->queues[queue_index]);
1057 vfree(be->vif->queues);
1058 be->vif->queues = NULL;
1059 be->vif->num_queues = 0;
1060 xenvif_disconnect_ctrl(be->vif);
1061 return;
1062}
1063
1064
1065static int connect_data_rings(struct backend_info *be,
1066 struct xenvif_queue *queue)
1067{
1068 struct xenbus_device *dev = be->dev;
1069 unsigned int num_queues = queue->vif->num_queues;
1070 unsigned long tx_ring_ref, rx_ring_ref;
1071 unsigned int tx_evtchn, rx_evtchn;
1072 int err;
1073 char *xspath;
1074 size_t xspathsize;
1075 const size_t xenstore_path_ext_size = 11;
1076
1077
1078
1079
1080
1081
1082
1083 if (num_queues == 1) {
1084 xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
1085 if (!xspath) {
1086 xenbus_dev_fatal(dev, -ENOMEM,
1087 "reading ring references");
1088 return -ENOMEM;
1089 }
1090 strcpy(xspath, dev->otherend);
1091 } else {
1092 xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
1093 xspath = kzalloc(xspathsize, GFP_KERNEL);
1094 if (!xspath) {
1095 xenbus_dev_fatal(dev, -ENOMEM,
1096 "reading ring references");
1097 return -ENOMEM;
1098 }
1099 snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
1100 queue->id);
1101 }
1102
1103 err = xenbus_gather(XBT_NIL, xspath,
1104 "tx-ring-ref", "%lu", &tx_ring_ref,
1105 "rx-ring-ref", "%lu", &rx_ring_ref, NULL);
1106 if (err) {
1107 xenbus_dev_fatal(dev, err,
1108 "reading %s/ring-ref",
1109 xspath);
1110 goto err;
1111 }
1112
1113
1114 err = xenbus_gather(XBT_NIL, xspath,
1115 "event-channel-tx", "%u", &tx_evtchn,
1116 "event-channel-rx", "%u", &rx_evtchn, NULL);
1117 if (err < 0) {
1118 err = xenbus_scanf(XBT_NIL, xspath,
1119 "event-channel", "%u", &tx_evtchn);
1120 if (err < 0) {
1121 xenbus_dev_fatal(dev, err,
1122 "reading %s/event-channel(-tx/rx)",
1123 xspath);
1124 goto err;
1125 }
1126 rx_evtchn = tx_evtchn;
1127 }
1128
1129
1130 err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
1131 tx_evtchn, rx_evtchn);
1132 if (err) {
1133 xenbus_dev_fatal(dev, err,
1134 "mapping shared-frames %lu/%lu port tx %u rx %u",
1135 tx_ring_ref, rx_ring_ref,
1136 tx_evtchn, rx_evtchn);
1137 goto err;
1138 }
1139
1140 err = 0;
1141err:
1142 kfree(xspath);
1143 return err;
1144}
1145
1146static int read_xenbus_vif_flags(struct backend_info *be)
1147{
1148 struct xenvif *vif = be->vif;
1149 struct xenbus_device *dev = be->dev;
1150 unsigned int rx_copy;
1151 int err;
1152
1153 err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
1154 &rx_copy);
1155 if (err == -ENOENT) {
1156 err = 0;
1157 rx_copy = 0;
1158 }
1159 if (err < 0) {
1160 xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
1161 dev->otherend);
1162 return err;
1163 }
1164 if (!rx_copy)
1165 return -EOPNOTSUPP;
1166
1167 if (!xenbus_read_unsigned(dev->otherend, "feature-rx-notify", 0)) {
1168
1169
1170
1171
1172 be->vif->drain_timeout = msecs_to_jiffies(30);
1173 be->vif->stall_timeout = 0;
1174 }
1175
1176 vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0);
1177
1178 vif->gso_mask = 0;
1179
1180 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0))
1181 vif->gso_mask |= GSO_BIT(TCPV4);
1182
1183 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv6", 0))
1184 vif->gso_mask |= GSO_BIT(TCPV6);
1185
1186 vif->ip_csum = !xenbus_read_unsigned(dev->otherend,
1187 "feature-no-csum-offload", 0);
1188
1189 vif->ipv6_csum = !!xenbus_read_unsigned(dev->otherend,
1190 "feature-ipv6-csum-offload", 0);
1191
1192 return 0;
1193}
1194
1195static const struct xenbus_device_id netback_ids[] = {
1196 { "vif" },
1197 { "" }
1198};
1199
1200static struct xenbus_driver netback_driver = {
1201 .ids = netback_ids,
1202 .probe = netback_probe,
1203 .remove = netback_remove,
1204 .uevent = netback_uevent,
1205 .otherend_changed = frontend_changed,
1206};
1207
1208int xenvif_xenbus_init(void)
1209{
1210 return xenbus_register_backend(&netback_driver);
1211}
1212
1213void xenvif_xenbus_fini(void)
1214{
1215 return xenbus_unregister_driver(&netback_driver);
1216}
1217
