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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 if (be->vif) {
496 xen_unregister_watchers(be->vif);
497#ifdef CONFIG_DEBUG_FS
498 xenvif_debugfs_delif(be->vif);
499#endif
500 xenvif_disconnect_data(be->vif);
501 xenvif_disconnect_ctrl(be->vif);
502 }
503}
504
505static void backend_connect(struct backend_info *be)
506{
507 if (be->vif)
508 connect(be);
509}
510
511static inline void backend_switch_state(struct backend_info *be,
512 enum xenbus_state state)
513{
514 struct xenbus_device *dev = be->dev;
515
516 pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
517 be->state = state;
518
519
520
521
522 if (!be->have_hotplug_status_watch)
523 xenbus_switch_state(dev, state);
524}
525
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545
546static void set_backend_state(struct backend_info *be,
547 enum xenbus_state state)
548{
549 while (be->state != state) {
550 switch (be->state) {
551 case XenbusStateInitialising:
552 switch (state) {
553 case XenbusStateInitWait:
554 case XenbusStateConnected:
555 case XenbusStateClosing:
556 backend_switch_state(be, XenbusStateInitWait);
557 break;
558 case XenbusStateClosed:
559 backend_switch_state(be, XenbusStateClosed);
560 break;
561 default:
562 BUG();
563 }
564 break;
565 case XenbusStateClosed:
566 switch (state) {
567 case XenbusStateInitWait:
568 case XenbusStateConnected:
569 backend_switch_state(be, XenbusStateInitWait);
570 break;
571 case XenbusStateClosing:
572 backend_switch_state(be, XenbusStateClosing);
573 break;
574 default:
575 BUG();
576 }
577 break;
578 case XenbusStateInitWait:
579 switch (state) {
580 case XenbusStateConnected:
581 backend_connect(be);
582 backend_switch_state(be, XenbusStateConnected);
583 break;
584 case XenbusStateClosing:
585 case XenbusStateClosed:
586 backend_switch_state(be, XenbusStateClosing);
587 break;
588 default:
589 BUG();
590 }
591 break;
592 case XenbusStateConnected:
593 switch (state) {
594 case XenbusStateInitWait:
595 case XenbusStateClosing:
596 case XenbusStateClosed:
597 backend_disconnect(be);
598 backend_switch_state(be, XenbusStateClosing);
599 break;
600 default:
601 BUG();
602 }
603 break;
604 case XenbusStateClosing:
605 switch (state) {
606 case XenbusStateInitWait:
607 case XenbusStateConnected:
608 case XenbusStateClosed:
609 backend_switch_state(be, XenbusStateClosed);
610 break;
611 default:
612 BUG();
613 }
614 break;
615 default:
616 BUG();
617 }
618 }
619}
620
621
622
623
624static void frontend_changed(struct xenbus_device *dev,
625 enum xenbus_state frontend_state)
626{
627 struct backend_info *be = dev_get_drvdata(&dev->dev);
628
629 pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
630
631 be->frontend_state = frontend_state;
632
633 switch (frontend_state) {
634 case XenbusStateInitialising:
635 set_backend_state(be, XenbusStateInitWait);
636 break;
637
638 case XenbusStateInitialised:
639 break;
640
641 case XenbusStateConnected:
642 set_backend_state(be, XenbusStateConnected);
643 break;
644
645 case XenbusStateClosing:
646 set_backend_state(be, XenbusStateClosing);
647 break;
648
649 case XenbusStateClosed:
650 set_backend_state(be, XenbusStateClosed);
651 if (xenbus_dev_is_online(dev))
652 break;
653
654 case XenbusStateUnknown:
655 set_backend_state(be, XenbusStateClosed);
656 device_unregister(&dev->dev);
657 break;
658
659 default:
660 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
661 frontend_state);
662 break;
663 }
664}
665
666
667static void xen_net_read_rate(struct xenbus_device *dev,
668 unsigned long *bytes, unsigned long *usec)
669{
670 char *s, *e;
671 unsigned long b, u;
672 char *ratestr;
673
674
675 *bytes = ~0UL;
676 *usec = 0;
677
678 ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
679 if (IS_ERR(ratestr))
680 return;
681
682 s = ratestr;
683 b = simple_strtoul(s, &e, 10);
684 if ((s == e) || (*e != ','))
685 goto fail;
686
687 s = e + 1;
688 u = simple_strtoul(s, &e, 10);
689 if ((s == e) || (*e != '\0'))
690 goto fail;
691
692 *bytes = b;
693 *usec = u;
694
695 kfree(ratestr);
696 return;
697
698 fail:
699 pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
700 kfree(ratestr);
701}
702
703static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
704{
705 char *s, *e, *macstr;
706 int i;
707
708 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
709 if (IS_ERR(macstr))
710 return PTR_ERR(macstr);
711
712 for (i = 0; i < ETH_ALEN; i++) {
713 mac[i] = simple_strtoul(s, &e, 16);
714 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
715 kfree(macstr);
716 return -ENOENT;
717 }
718 s = e+1;
719 }
720
721 kfree(macstr);
722 return 0;
723}
724
725static void xen_net_rate_changed(struct xenbus_watch *watch,
726 const char **vec, unsigned int len)
727{
728 struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
729 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
730 unsigned long credit_bytes;
731 unsigned long credit_usec;
732 unsigned int queue_index;
733
734 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
735 for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
736 struct xenvif_queue *queue = &vif->queues[queue_index];
737
738 queue->credit_bytes = credit_bytes;
739 queue->credit_usec = credit_usec;
740 if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
741 queue->remaining_credit > queue->credit_bytes) {
742 queue->remaining_credit = queue->credit_bytes;
743 }
744 }
745}
746
747static int xen_register_credit_watch(struct xenbus_device *dev,
748 struct xenvif *vif)
749{
750 int err = 0;
751 char *node;
752 unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
753
754 if (vif->credit_watch.node)
755 return -EADDRINUSE;
756
757 node = kmalloc(maxlen, GFP_KERNEL);
758 if (!node)
759 return -ENOMEM;
760 snprintf(node, maxlen, "%s/rate", dev->nodename);
761 vif->credit_watch.node = node;
762 vif->credit_watch.callback = xen_net_rate_changed;
763 err = register_xenbus_watch(&vif->credit_watch);
764 if (err) {
765 pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
766 kfree(node);
767 vif->credit_watch.node = NULL;
768 vif->credit_watch.callback = NULL;
769 }
770 return err;
771}
772
773static void xen_unregister_credit_watch(struct xenvif *vif)
774{
775 if (vif->credit_watch.node) {
776 unregister_xenbus_watch(&vif->credit_watch);
777 kfree(vif->credit_watch.node);
778 vif->credit_watch.node = NULL;
779 }
780}
781
782static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
783 const char **vec, unsigned int len)
784{
785 struct xenvif *vif = container_of(watch, struct xenvif,
786 mcast_ctrl_watch);
787 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
788 int val;
789
790 if (xenbus_scanf(XBT_NIL, dev->otherend,
791 "request-multicast-control", "%d", &val) < 0)
792 val = 0;
793 vif->multicast_control = !!val;
794}
795
796static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
797 struct xenvif *vif)
798{
799 int err = 0;
800 char *node;
801 unsigned maxlen = strlen(dev->otherend) +
802 sizeof("/request-multicast-control");
803
804 if (vif->mcast_ctrl_watch.node) {
805 pr_err_ratelimited("Watch is already registered\n");
806 return -EADDRINUSE;
807 }
808
809 node = kmalloc(maxlen, GFP_KERNEL);
810 if (!node) {
811 pr_err("Failed to allocate memory for watch\n");
812 return -ENOMEM;
813 }
814 snprintf(node, maxlen, "%s/request-multicast-control",
815 dev->otherend);
816 vif->mcast_ctrl_watch.node = node;
817 vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
818 err = register_xenbus_watch(&vif->mcast_ctrl_watch);
819 if (err) {
820 pr_err("Failed to set watcher %s\n",
821 vif->mcast_ctrl_watch.node);
822 kfree(node);
823 vif->mcast_ctrl_watch.node = NULL;
824 vif->mcast_ctrl_watch.callback = NULL;
825 }
826 return err;
827}
828
829static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
830{
831 if (vif->mcast_ctrl_watch.node) {
832 unregister_xenbus_watch(&vif->mcast_ctrl_watch);
833 kfree(vif->mcast_ctrl_watch.node);
834 vif->mcast_ctrl_watch.node = NULL;
835 }
836}
837
838static void xen_register_watchers(struct xenbus_device *dev,
839 struct xenvif *vif)
840{
841 xen_register_credit_watch(dev, vif);
842 xen_register_mcast_ctrl_watch(dev, vif);
843}
844
845static void xen_unregister_watchers(struct xenvif *vif)
846{
847 xen_unregister_mcast_ctrl_watch(vif);
848 xen_unregister_credit_watch(vif);
849}
850
851static void unregister_hotplug_status_watch(struct backend_info *be)
852{
853 if (be->have_hotplug_status_watch) {
854 unregister_xenbus_watch(&be->hotplug_status_watch);
855 kfree(be->hotplug_status_watch.node);
856 }
857 be->have_hotplug_status_watch = 0;
858}
859
860static void hotplug_status_changed(struct xenbus_watch *watch,
861 const char **vec,
862 unsigned int vec_size)
863{
864 struct backend_info *be = container_of(watch,
865 struct backend_info,
866 hotplug_status_watch);
867 char *str;
868 unsigned int len;
869
870 str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
871 if (IS_ERR(str))
872 return;
873 if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
874
875 xenbus_switch_state(be->dev, be->state);
876
877
878 unregister_hotplug_status_watch(be);
879 }
880 kfree(str);
881}
882
883static int connect_ctrl_ring(struct backend_info *be)
884{
885 struct xenbus_device *dev = be->dev;
886 struct xenvif *vif = be->vif;
887 unsigned int val;
888 grant_ref_t ring_ref;
889 unsigned int evtchn;
890 int err;
891
892 err = xenbus_gather(XBT_NIL, dev->otherend,
893 "ctrl-ring-ref", "%u", &val, NULL);
894 if (err)
895 goto done;
896
897 ring_ref = val;
898
899 err = xenbus_gather(XBT_NIL, dev->otherend,
900 "event-channel-ctrl", "%u", &val, NULL);
901 if (err) {
902 xenbus_dev_fatal(dev, err,
903 "reading %s/event-channel-ctrl",
904 dev->otherend);
905 goto fail;
906 }
907
908 evtchn = val;
909
910 err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
911 if (err) {
912 xenbus_dev_fatal(dev, err,
913 "mapping shared-frame %u port %u",
914 ring_ref, evtchn);
915 goto fail;
916 }
917
918done:
919 return 0;
920
921fail:
922 return err;
923}
924
925static void connect(struct backend_info *be)
926{
927 int err;
928 struct xenbus_device *dev = be->dev;
929 unsigned long credit_bytes, credit_usec;
930 unsigned int queue_index;
931 unsigned int requested_num_queues;
932 struct xenvif_queue *queue;
933
934
935
936
937 err = xenbus_scanf(XBT_NIL, dev->otherend,
938 "multi-queue-num-queues",
939 "%u", &requested_num_queues);
940 if (err < 0) {
941 requested_num_queues = 1;
942 } else if (requested_num_queues > xenvif_max_queues) {
943
944 xenbus_dev_fatal(dev, err,
945 "guest requested %u queues, exceeding the maximum of %u.",
946 requested_num_queues, xenvif_max_queues);
947 return;
948 }
949
950 err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
951 if (err) {
952 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
953 return;
954 }
955
956 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
957 xen_unregister_watchers(be->vif);
958 xen_register_watchers(dev, be->vif);
959 read_xenbus_vif_flags(be);
960
961 err = connect_ctrl_ring(be);
962 if (err) {
963 xenbus_dev_fatal(dev, err, "connecting control ring");
964 return;
965 }
966
967
968 be->vif->queues = vzalloc(requested_num_queues *
969 sizeof(struct xenvif_queue));
970 if (!be->vif->queues) {
971 xenbus_dev_fatal(dev, -ENOMEM,
972 "allocating queues");
973 return;
974 }
975
976 be->vif->num_queues = requested_num_queues;
977 be->vif->stalled_queues = requested_num_queues;
978
979 for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
980 queue = &be->vif->queues[queue_index];
981 queue->vif = be->vif;
982 queue->id = queue_index;
983 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
984 be->vif->dev->name, queue->id);
985
986 err = xenvif_init_queue(queue);
987 if (err) {
988
989
990
991
992
993
994 be->vif->num_queues = queue_index;
995 goto err;
996 }
997
998 queue->credit_bytes = credit_bytes;
999 queue->remaining_credit = credit_bytes;
1000 queue->credit_usec = credit_usec;
1001
1002 err = connect_data_rings(be, queue);
1003 if (err) {
1004
1005
1006
1007
1008
1009 xenvif_deinit_queue(queue);
1010 be->vif->num_queues = queue_index;
1011 goto err;
1012 }
1013 }
1014
1015#ifdef CONFIG_DEBUG_FS
1016 xenvif_debugfs_addif(be->vif);
1017#endif
1018
1019
1020
1021
1022 rtnl_lock();
1023 netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
1024 netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
1025 rtnl_unlock();
1026
1027 xenvif_carrier_on(be->vif);
1028
1029 unregister_hotplug_status_watch(be);
1030 err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
1031 hotplug_status_changed,
1032 "%s/%s", dev->nodename, "hotplug-status");
1033 if (!err)
1034 be->have_hotplug_status_watch = 1;
1035
1036 netif_tx_wake_all_queues(be->vif->dev);
1037
1038 return;
1039
1040err:
1041 if (be->vif->num_queues > 0)
1042 xenvif_disconnect_data(be->vif);
1043 vfree(be->vif->queues);
1044 be->vif->queues = NULL;
1045 be->vif->num_queues = 0;
1046 xenvif_disconnect_ctrl(be->vif);
1047 return;
1048}
1049
1050
1051static int connect_data_rings(struct backend_info *be,
1052 struct xenvif_queue *queue)
1053{
1054 struct xenbus_device *dev = be->dev;
1055 unsigned int num_queues = queue->vif->num_queues;
1056 unsigned long tx_ring_ref, rx_ring_ref;
1057 unsigned int tx_evtchn, rx_evtchn;
1058 int err;
1059 char *xspath;
1060 size_t xspathsize;
1061 const size_t xenstore_path_ext_size = 11;
1062
1063
1064
1065
1066
1067
1068
1069 if (num_queues == 1) {
1070 xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
1071 if (!xspath) {
1072 xenbus_dev_fatal(dev, -ENOMEM,
1073 "reading ring references");
1074 return -ENOMEM;
1075 }
1076 strcpy(xspath, dev->otherend);
1077 } else {
1078 xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
1079 xspath = kzalloc(xspathsize, GFP_KERNEL);
1080 if (!xspath) {
1081 xenbus_dev_fatal(dev, -ENOMEM,
1082 "reading ring references");
1083 return -ENOMEM;
1084 }
1085 snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
1086 queue->id);
1087 }
1088
1089 err = xenbus_gather(XBT_NIL, xspath,
1090 "tx-ring-ref", "%lu", &tx_ring_ref,
1091 "rx-ring-ref", "%lu", &rx_ring_ref, NULL);
1092 if (err) {
1093 xenbus_dev_fatal(dev, err,
1094 "reading %s/ring-ref",
1095 xspath);
1096 goto err;
1097 }
1098
1099
1100 err = xenbus_gather(XBT_NIL, xspath,
1101 "event-channel-tx", "%u", &tx_evtchn,
1102 "event-channel-rx", "%u", &rx_evtchn, NULL);
1103 if (err < 0) {
1104 err = xenbus_scanf(XBT_NIL, xspath,
1105 "event-channel", "%u", &tx_evtchn);
1106 if (err < 0) {
1107 xenbus_dev_fatal(dev, err,
1108 "reading %s/event-channel(-tx/rx)",
1109 xspath);
1110 goto err;
1111 }
1112 rx_evtchn = tx_evtchn;
1113 }
1114
1115
1116 err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
1117 tx_evtchn, rx_evtchn);
1118 if (err) {
1119 xenbus_dev_fatal(dev, err,
1120 "mapping shared-frames %lu/%lu port tx %u rx %u",
1121 tx_ring_ref, rx_ring_ref,
1122 tx_evtchn, rx_evtchn);
1123 goto err;
1124 }
1125
1126 err = 0;
1127err:
1128 kfree(xspath);
1129 return err;
1130}
1131
1132static int read_xenbus_vif_flags(struct backend_info *be)
1133{
1134 struct xenvif *vif = be->vif;
1135 struct xenbus_device *dev = be->dev;
1136 unsigned int rx_copy;
1137 int err, val;
1138
1139 err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
1140 &rx_copy);
1141 if (err == -ENOENT) {
1142 err = 0;
1143 rx_copy = 0;
1144 }
1145 if (err < 0) {
1146 xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
1147 dev->otherend);
1148 return err;
1149 }
1150 if (!rx_copy)
1151 return -EOPNOTSUPP;
1152
1153 if (xenbus_scanf(XBT_NIL, dev->otherend,
1154 "feature-rx-notify", "%d", &val) < 0)
1155 val = 0;
1156 if (!val) {
1157
1158
1159
1160
1161 be->vif->drain_timeout = msecs_to_jiffies(30);
1162 be->vif->stall_timeout = 0;
1163 }
1164
1165 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg",
1166 "%d", &val) < 0)
1167 val = 0;
1168 vif->can_sg = !!val;
1169
1170 vif->gso_mask = 0;
1171
1172 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4",
1173 "%d", &val) < 0)
1174 val = 0;
1175 if (val)
1176 vif->gso_mask |= GSO_BIT(TCPV4);
1177
1178 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6",
1179 "%d", &val) < 0)
1180 val = 0;
1181 if (val)
1182 vif->gso_mask |= GSO_BIT(TCPV6);
1183
1184 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload",
1185 "%d", &val) < 0)
1186 val = 0;
1187 vif->ip_csum = !val;
1188
1189 if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-ipv6-csum-offload",
1190 "%d", &val) < 0)
1191 val = 0;
1192 vif->ipv6_csum = !!val;
1193
1194 return 0;
1195}
1196
1197static const struct xenbus_device_id netback_ids[] = {
1198 { "vif" },
1199 { "" }
1200};
1201
1202static struct xenbus_driver netback_driver = {
1203 .ids = netback_ids,
1204 .probe = netback_probe,
1205 .remove = netback_remove,
1206 .uevent = netback_uevent,
1207 .otherend_changed = frontend_changed,
1208};
1209
1210int xenvif_xenbus_init(void)
1211{
1212 return xenbus_register_backend(&netback_driver);
1213}
1214
1215void xenvif_xenbus_fini(void)
1216{
1217 return xenbus_unregister_driver(&netback_driver);
1218}
1219
