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9#include "common.h"
10#include <linux/vmalloc.h>
11#include <linux/rtnetlink.h>
12
13static int connect_data_rings(struct backend_info *be,
14 struct xenvif_queue *queue);
15static void connect(struct backend_info *be);
16static int read_xenbus_vif_flags(struct backend_info *be);
17static int backend_create_xenvif(struct backend_info *be);
18static void unregister_hotplug_status_watch(struct backend_info *be);
19static void xen_unregister_watchers(struct xenvif *vif);
20static void set_backend_state(struct backend_info *be,
21 enum xenbus_state state);
22
23#ifdef CONFIG_DEBUG_FS
24struct dentry *xen_netback_dbg_root = NULL;
25
26static int xenvif_read_io_ring(struct seq_file *m, void *v)
27{
28 struct xenvif_queue *queue = m->private;
29 struct xen_netif_tx_back_ring *tx_ring = &queue->tx;
30 struct xen_netif_rx_back_ring *rx_ring = &queue->rx;
31 struct netdev_queue *dev_queue;
32
33 if (tx_ring->sring) {
34 struct xen_netif_tx_sring *sring = tx_ring->sring;
35
36 seq_printf(m, "Queue %d\nTX: nr_ents %u\n", queue->id,
37 tx_ring->nr_ents);
38 seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
39 sring->req_prod,
40 sring->req_prod - sring->rsp_prod,
41 tx_ring->req_cons,
42 tx_ring->req_cons - sring->rsp_prod,
43 sring->req_event,
44 sring->req_event - sring->rsp_prod);
45 seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n",
46 sring->rsp_prod,
47 tx_ring->rsp_prod_pvt,
48 tx_ring->rsp_prod_pvt - sring->rsp_prod,
49 sring->rsp_event,
50 sring->rsp_event - sring->rsp_prod);
51 seq_printf(m, "pending prod %u pending cons %u nr_pending_reqs %u\n",
52 queue->pending_prod,
53 queue->pending_cons,
54 nr_pending_reqs(queue));
55 seq_printf(m, "dealloc prod %u dealloc cons %u dealloc_queue %u\n\n",
56 queue->dealloc_prod,
57 queue->dealloc_cons,
58 queue->dealloc_prod - queue->dealloc_cons);
59 }
60
61 if (rx_ring->sring) {
62 struct xen_netif_rx_sring *sring = rx_ring->sring;
63
64 seq_printf(m, "RX: nr_ents %u\n", rx_ring->nr_ents);
65 seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n",
66 sring->req_prod,
67 sring->req_prod - sring->rsp_prod,
68 rx_ring->req_cons,
69 rx_ring->req_cons - sring->rsp_prod,
70 sring->req_event,
71 sring->req_event - sring->rsp_prod);
72 seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n\n",
73 sring->rsp_prod,
74 rx_ring->rsp_prod_pvt,
75 rx_ring->rsp_prod_pvt - sring->rsp_prod,
76 sring->rsp_event,
77 sring->rsp_event - sring->rsp_prod);
78 }
79
80 seq_printf(m, "NAPI state: %lx NAPI weight: %d TX queue len %u\n"
81 "Credit timer_pending: %d, credit: %lu, usec: %lu\n"
82 "remaining: %lu, expires: %lu, now: %lu\n",
83 queue->napi.state, queue->napi.weight,
84 skb_queue_len(&queue->tx_queue),
85 timer_pending(&queue->credit_timeout),
86 queue->credit_bytes,
87 queue->credit_usec,
88 queue->remaining_credit,
89 queue->credit_timeout.expires,
90 jiffies);
91
92 dev_queue = netdev_get_tx_queue(queue->vif->dev, queue->id);
93
94 seq_printf(m, "\nRx internal queue: len %u max %u pkts %u %s\n",
95 queue->rx_queue_len, queue->rx_queue_max,
96 skb_queue_len(&queue->rx_queue),
97 netif_tx_queue_stopped(dev_queue) ? "stopped" : "running");
98
99 return 0;
100}
101
102#define XENVIF_KICK_STR "kick"
103#define BUFFER_SIZE 32
104
105static ssize_t
106xenvif_write_io_ring(struct file *filp, const char __user *buf, size_t count,
107 loff_t *ppos)
108{
109 struct xenvif_queue *queue =
110 ((struct seq_file *)filp->private_data)->private;
111 int len;
112 char write[BUFFER_SIZE];
113
114
115 if (*ppos != 0)
116 return 0;
117 if (count >= sizeof(write))
118 return -ENOSPC;
119
120 len = simple_write_to_buffer(write,
121 sizeof(write) - 1,
122 ppos,
123 buf,
124 count);
125 if (len < 0)
126 return len;
127
128 write[len] = '\0';
129
130 if (!strncmp(write, XENVIF_KICK_STR, sizeof(XENVIF_KICK_STR) - 1))
131 xenvif_interrupt(0, (void *)queue);
132 else {
133 pr_warn("Unknown command to io_ring_q%d. Available: kick\n",
134 queue->id);
135 count = -EINVAL;
136 }
137 return count;
138}
139
140static int xenvif_io_ring_open(struct inode *inode, struct file *filp)
141{
142 int ret;
143 void *queue = NULL;
144
145 if (inode->i_private)
146 queue = inode->i_private;
147 ret = single_open(filp, xenvif_read_io_ring, queue);
148 filp->f_mode |= FMODE_PWRITE;
149 return ret;
150}
151
152static const struct file_operations xenvif_dbg_io_ring_ops_fops = {
153 .owner = THIS_MODULE,
154 .open = xenvif_io_ring_open,
155 .read = seq_read,
156 .llseek = seq_lseek,
157 .release = single_release,
158 .write = xenvif_write_io_ring,
159};
160
161static int xenvif_ctrl_show(struct seq_file *m, void *v)
162{
163 struct xenvif *vif = m->private;
164
165 xenvif_dump_hash_info(vif, m);
166
167 return 0;
168}
169DEFINE_SHOW_ATTRIBUTE(xenvif_ctrl);
170
171static void xenvif_debugfs_addif(struct xenvif *vif)
172{
173 struct dentry *pfile;
174 int i;
175
176 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
177 return;
178
179 vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name,
180 xen_netback_dbg_root);
181 if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root)) {
182 for (i = 0; i < vif->num_queues; ++i) {
183 char filename[sizeof("io_ring_q") + 4];
184
185 snprintf(filename, sizeof(filename), "io_ring_q%d", i);
186 pfile = debugfs_create_file(filename,
187 0600,
188 vif->xenvif_dbg_root,
189 &vif->queues[i],
190 &xenvif_dbg_io_ring_ops_fops);
191 if (IS_ERR_OR_NULL(pfile))
192 pr_warn("Creation of io_ring file returned %ld!\n",
193 PTR_ERR(pfile));
194 }
195
196 if (vif->ctrl_irq) {
197 pfile = debugfs_create_file("ctrl",
198 0400,
199 vif->xenvif_dbg_root,
200 vif,
201 &xenvif_ctrl_fops);
202 if (IS_ERR_OR_NULL(pfile))
203 pr_warn("Creation of ctrl file returned %ld!\n",
204 PTR_ERR(pfile));
205 }
206 } else
207 netdev_warn(vif->dev,
208 "Creation of vif debugfs dir returned %ld!\n",
209 PTR_ERR(vif->xenvif_dbg_root));
210}
211
212static void xenvif_debugfs_delif(struct xenvif *vif)
213{
214 if (IS_ERR_OR_NULL(xen_netback_dbg_root))
215 return;
216
217 debugfs_remove_recursive(vif->xenvif_dbg_root);
218 vif->xenvif_dbg_root = NULL;
219}
220#endif
221
222static int netback_remove(struct xenbus_device *dev)
223{
224 struct backend_info *be = dev_get_drvdata(&dev->dev);
225
226 set_backend_state(be, XenbusStateClosed);
227
228 unregister_hotplug_status_watch(be);
229 if (be->vif) {
230 kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
231 xen_unregister_watchers(be->vif);
232 xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
233 xenvif_free(be->vif);
234 be->vif = NULL;
235 }
236 kfree(be->hotplug_script);
237 kfree(be);
238 dev_set_drvdata(&dev->dev, NULL);
239 return 0;
240}
241
242
243
244
245
246
247static int netback_probe(struct xenbus_device *dev,
248 const struct xenbus_device_id *id)
249{
250 const char *message;
251 struct xenbus_transaction xbt;
252 int err;
253 int sg;
254 const char *script;
255 struct backend_info *be = kzalloc(sizeof(struct backend_info),
256 GFP_KERNEL);
257 if (!be) {
258 xenbus_dev_fatal(dev, -ENOMEM,
259 "allocating backend structure");
260 return -ENOMEM;
261 }
262
263 be->dev = dev;
264 dev_set_drvdata(&dev->dev, be);
265
266 be->state = XenbusStateInitialising;
267 err = xenbus_switch_state(dev, XenbusStateInitialising);
268 if (err)
269 goto fail;
270
271 sg = 1;
272
273 do {
274 err = xenbus_transaction_start(&xbt);
275 if (err) {
276 xenbus_dev_fatal(dev, err, "starting transaction");
277 goto fail;
278 }
279
280 err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
281 if (err) {
282 message = "writing feature-sg";
283 goto abort_transaction;
284 }
285
286 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
287 "%d", sg);
288 if (err) {
289 message = "writing feature-gso-tcpv4";
290 goto abort_transaction;
291 }
292
293 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
294 "%d", sg);
295 if (err) {
296 message = "writing feature-gso-tcpv6";
297 goto abort_transaction;
298 }
299
300
301 err = xenbus_printf(xbt, dev->nodename,
302 "feature-ipv6-csum-offload",
303 "%d", 1);
304 if (err) {
305 message = "writing feature-ipv6-csum-offload";
306 goto abort_transaction;
307 }
308
309
310 err = xenbus_printf(xbt, dev->nodename,
311 "feature-rx-copy", "%d", 1);
312 if (err) {
313 message = "writing feature-rx-copy";
314 goto abort_transaction;
315 }
316
317
318
319
320
321 err = xenbus_printf(xbt, dev->nodename,
322 "feature-rx-flip", "%d", 0);
323 if (err) {
324 message = "writing feature-rx-flip";
325 goto abort_transaction;
326 }
327
328
329 err = xenbus_printf(xbt, dev->nodename,
330 "feature-multicast-control", "%d", 1);
331 if (err) {
332 message = "writing feature-multicast-control";
333 goto abort_transaction;
334 }
335
336 err = xenbus_printf(xbt, dev->nodename,
337 "feature-dynamic-multicast-control",
338 "%d", 1);
339 if (err) {
340 message = "writing feature-dynamic-multicast-control";
341 goto abort_transaction;
342 }
343
344 err = xenbus_transaction_end(xbt, 0);
345 } while (err == -EAGAIN);
346
347 if (err) {
348 xenbus_dev_fatal(dev, err, "completing transaction");
349 goto fail;
350 }
351
352
353
354
355
356 err = xenbus_printf(XBT_NIL, dev->nodename,
357 "feature-split-event-channels",
358 "%u", separate_tx_rx_irq);
359 if (err)
360 pr_debug("Error writing feature-split-event-channels\n");
361
362
363 err = xenbus_printf(XBT_NIL, dev->nodename,
364 "multi-queue-max-queues", "%u", xenvif_max_queues);
365 if (err)
366 pr_debug("Error writing multi-queue-max-queues\n");
367
368 err = xenbus_printf(XBT_NIL, dev->nodename,
369 "feature-ctrl-ring",
370 "%u", true);
371 if (err)
372 pr_debug("Error writing feature-ctrl-ring\n");
373
374 script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
375 if (IS_ERR(script)) {
376 err = PTR_ERR(script);
377 xenbus_dev_fatal(dev, err, "reading script");
378 goto fail;
379 }
380
381 be->hotplug_script = script;
382
383
384
385 err = backend_create_xenvif(be);
386 if (err)
387 goto fail;
388
389 return 0;
390
391abort_transaction:
392 xenbus_transaction_end(xbt, 1);
393 xenbus_dev_fatal(dev, err, "%s", message);
394fail:
395 pr_debug("failed\n");
396 netback_remove(dev);
397 return err;
398}
399
400
401
402
403
404
405
406static int netback_uevent(struct xenbus_device *xdev,
407 struct kobj_uevent_env *env)
408{
409 struct backend_info *be = dev_get_drvdata(&xdev->dev);
410
411 if (!be)
412 return 0;
413
414 if (add_uevent_var(env, "script=%s", be->hotplug_script))
415 return -ENOMEM;
416
417 if (!be->vif)
418 return 0;
419
420 return add_uevent_var(env, "vif=%s", be->vif->dev->name);
421}
422
423
424static int backend_create_xenvif(struct backend_info *be)
425{
426 int err;
427 long handle;
428 struct xenbus_device *dev = be->dev;
429 struct xenvif *vif;
430
431 if (be->vif != NULL)
432 return 0;
433
434 err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
435 if (err != 1) {
436 xenbus_dev_fatal(dev, err, "reading handle");
437 return (err < 0) ? err : -EINVAL;
438 }
439
440 vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
441 if (IS_ERR(vif)) {
442 err = PTR_ERR(vif);
443 xenbus_dev_fatal(dev, err, "creating interface");
444 return err;
445 }
446 be->vif = vif;
447 vif->be = be;
448
449 kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
450 return 0;
451}
452
453static void backend_disconnect(struct backend_info *be)
454{
455 struct xenvif *vif = be->vif;
456
457 if (vif) {
458 unsigned int num_queues = vif->num_queues;
459 unsigned int queue_index;
460
461 xen_unregister_watchers(vif);
462#ifdef CONFIG_DEBUG_FS
463 xenvif_debugfs_delif(vif);
464#endif
465 xenvif_disconnect_data(vif);
466
467
468
469
470 vif->num_queues = 0;
471 synchronize_net();
472
473 for (queue_index = 0; queue_index < num_queues; ++queue_index)
474 xenvif_deinit_queue(&vif->queues[queue_index]);
475
476 vfree(vif->queues);
477 vif->queues = NULL;
478
479 xenvif_disconnect_ctrl(vif);
480 }
481}
482
483static void backend_connect(struct backend_info *be)
484{
485 if (be->vif)
486 connect(be);
487}
488
489static inline void backend_switch_state(struct backend_info *be,
490 enum xenbus_state state)
491{
492 struct xenbus_device *dev = be->dev;
493
494 pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
495 be->state = state;
496
497
498
499
500 if (!be->have_hotplug_status_watch)
501 xenbus_switch_state(dev, state);
502}
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523
524static void set_backend_state(struct backend_info *be,
525 enum xenbus_state state)
526{
527 while (be->state != state) {
528 switch (be->state) {
529 case XenbusStateInitialising:
530 switch (state) {
531 case XenbusStateInitWait:
532 case XenbusStateConnected:
533 case XenbusStateClosing:
534 backend_switch_state(be, XenbusStateInitWait);
535 break;
536 case XenbusStateClosed:
537 backend_switch_state(be, XenbusStateClosed);
538 break;
539 default:
540 BUG();
541 }
542 break;
543 case XenbusStateClosed:
544 switch (state) {
545 case XenbusStateInitWait:
546 case XenbusStateConnected:
547 backend_switch_state(be, XenbusStateInitWait);
548 break;
549 case XenbusStateClosing:
550 backend_switch_state(be, XenbusStateClosing);
551 break;
552 default:
553 BUG();
554 }
555 break;
556 case XenbusStateInitWait:
557 switch (state) {
558 case XenbusStateConnected:
559 backend_connect(be);
560 backend_switch_state(be, XenbusStateConnected);
561 break;
562 case XenbusStateClosing:
563 case XenbusStateClosed:
564 backend_switch_state(be, XenbusStateClosing);
565 break;
566 default:
567 BUG();
568 }
569 break;
570 case XenbusStateConnected:
571 switch (state) {
572 case XenbusStateInitWait:
573 case XenbusStateClosing:
574 case XenbusStateClosed:
575 backend_disconnect(be);
576 backend_switch_state(be, XenbusStateClosing);
577 break;
578 default:
579 BUG();
580 }
581 break;
582 case XenbusStateClosing:
583 switch (state) {
584 case XenbusStateInitWait:
585 case XenbusStateConnected:
586 case XenbusStateClosed:
587 backend_switch_state(be, XenbusStateClosed);
588 break;
589 default:
590 BUG();
591 }
592 break;
593 default:
594 BUG();
595 }
596 }
597}
598
599
600
601
602static void frontend_changed(struct xenbus_device *dev,
603 enum xenbus_state frontend_state)
604{
605 struct backend_info *be = dev_get_drvdata(&dev->dev);
606
607 pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
608
609 be->frontend_state = frontend_state;
610
611 switch (frontend_state) {
612 case XenbusStateInitialising:
613 set_backend_state(be, XenbusStateInitWait);
614 break;
615
616 case XenbusStateInitialised:
617 break;
618
619 case XenbusStateConnected:
620 set_backend_state(be, XenbusStateConnected);
621 break;
622
623 case XenbusStateClosing:
624 set_backend_state(be, XenbusStateClosing);
625 break;
626
627 case XenbusStateClosed:
628 set_backend_state(be, XenbusStateClosed);
629 if (xenbus_dev_is_online(dev))
630 break;
631
632 case XenbusStateUnknown:
633 set_backend_state(be, XenbusStateClosed);
634 device_unregister(&dev->dev);
635 break;
636
637 default:
638 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
639 frontend_state);
640 break;
641 }
642}
643
644
645static void xen_net_read_rate(struct xenbus_device *dev,
646 unsigned long *bytes, unsigned long *usec)
647{
648 char *s, *e;
649 unsigned long b, u;
650 char *ratestr;
651
652
653 *bytes = ~0UL;
654 *usec = 0;
655
656 ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
657 if (IS_ERR(ratestr))
658 return;
659
660 s = ratestr;
661 b = simple_strtoul(s, &e, 10);
662 if ((s == e) || (*e != ','))
663 goto fail;
664
665 s = e + 1;
666 u = simple_strtoul(s, &e, 10);
667 if ((s == e) || (*e != '\0'))
668 goto fail;
669
670 *bytes = b;
671 *usec = u;
672
673 kfree(ratestr);
674 return;
675
676 fail:
677 pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
678 kfree(ratestr);
679}
680
681static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
682{
683 char *s, *e, *macstr;
684 int i;
685
686 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
687 if (IS_ERR(macstr))
688 return PTR_ERR(macstr);
689
690 for (i = 0; i < ETH_ALEN; i++) {
691 mac[i] = simple_strtoul(s, &e, 16);
692 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
693 kfree(macstr);
694 return -ENOENT;
695 }
696 s = e+1;
697 }
698
699 kfree(macstr);
700 return 0;
701}
702
703static void xen_net_rate_changed(struct xenbus_watch *watch,
704 const char *path, const char *token)
705{
706 struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
707 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
708 unsigned long credit_bytes;
709 unsigned long credit_usec;
710 unsigned int queue_index;
711
712 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
713 for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
714 struct xenvif_queue *queue = &vif->queues[queue_index];
715
716 queue->credit_bytes = credit_bytes;
717 queue->credit_usec = credit_usec;
718 if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
719 queue->remaining_credit > queue->credit_bytes) {
720 queue->remaining_credit = queue->credit_bytes;
721 }
722 }
723}
724
725static int xen_register_credit_watch(struct xenbus_device *dev,
726 struct xenvif *vif)
727{
728 int err = 0;
729 char *node;
730 unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
731
732 if (vif->credit_watch.node)
733 return -EADDRINUSE;
734
735 node = kmalloc(maxlen, GFP_KERNEL);
736 if (!node)
737 return -ENOMEM;
738 snprintf(node, maxlen, "%s/rate", dev->nodename);
739 vif->credit_watch.node = node;
740 vif->credit_watch.callback = xen_net_rate_changed;
741 err = register_xenbus_watch(&vif->credit_watch);
742 if (err) {
743 pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
744 kfree(node);
745 vif->credit_watch.node = NULL;
746 vif->credit_watch.callback = NULL;
747 }
748 return err;
749}
750
751static void xen_unregister_credit_watch(struct xenvif *vif)
752{
753 if (vif->credit_watch.node) {
754 unregister_xenbus_watch(&vif->credit_watch);
755 kfree(vif->credit_watch.node);
756 vif->credit_watch.node = NULL;
757 }
758}
759
760static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
761 const char *path, const char *token)
762{
763 struct xenvif *vif = container_of(watch, struct xenvif,
764 mcast_ctrl_watch);
765 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
766
767 vif->multicast_control = !!xenbus_read_unsigned(dev->otherend,
768 "request-multicast-control", 0);
769}
770
771static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
772 struct xenvif *vif)
773{
774 int err = 0;
775 char *node;
776 unsigned maxlen = strlen(dev->otherend) +
777 sizeof("/request-multicast-control");
778
779 if (vif->mcast_ctrl_watch.node) {
780 pr_err_ratelimited("Watch is already registered\n");
781 return -EADDRINUSE;
782 }
783
784 node = kmalloc(maxlen, GFP_KERNEL);
785 if (!node) {
786 pr_err("Failed to allocate memory for watch\n");
787 return -ENOMEM;
788 }
789 snprintf(node, maxlen, "%s/request-multicast-control",
790 dev->otherend);
791 vif->mcast_ctrl_watch.node = node;
792 vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
793 err = register_xenbus_watch(&vif->mcast_ctrl_watch);
794 if (err) {
795 pr_err("Failed to set watcher %s\n",
796 vif->mcast_ctrl_watch.node);
797 kfree(node);
798 vif->mcast_ctrl_watch.node = NULL;
799 vif->mcast_ctrl_watch.callback = NULL;
800 }
801 return err;
802}
803
804static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
805{
806 if (vif->mcast_ctrl_watch.node) {
807 unregister_xenbus_watch(&vif->mcast_ctrl_watch);
808 kfree(vif->mcast_ctrl_watch.node);
809 vif->mcast_ctrl_watch.node = NULL;
810 }
811}
812
813static void xen_register_watchers(struct xenbus_device *dev,
814 struct xenvif *vif)
815{
816 xen_register_credit_watch(dev, vif);
817 xen_register_mcast_ctrl_watch(dev, vif);
818}
819
820static void xen_unregister_watchers(struct xenvif *vif)
821{
822 xen_unregister_mcast_ctrl_watch(vif);
823 xen_unregister_credit_watch(vif);
824}
825
826static void unregister_hotplug_status_watch(struct backend_info *be)
827{
828 if (be->have_hotplug_status_watch) {
829 unregister_xenbus_watch(&be->hotplug_status_watch);
830 kfree(be->hotplug_status_watch.node);
831 }
832 be->have_hotplug_status_watch = 0;
833}
834
835static void hotplug_status_changed(struct xenbus_watch *watch,
836 const char *path,
837 const char *token)
838{
839 struct backend_info *be = container_of(watch,
840 struct backend_info,
841 hotplug_status_watch);
842 char *str;
843 unsigned int len;
844
845 str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
846 if (IS_ERR(str))
847 return;
848 if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
849
850 xenbus_switch_state(be->dev, be->state);
851
852
853 unregister_hotplug_status_watch(be);
854 }
855 kfree(str);
856}
857
858static int connect_ctrl_ring(struct backend_info *be)
859{
860 struct xenbus_device *dev = be->dev;
861 struct xenvif *vif = be->vif;
862 unsigned int val;
863 grant_ref_t ring_ref;
864 unsigned int evtchn;
865 int err;
866
867 err = xenbus_scanf(XBT_NIL, dev->otherend,
868 "ctrl-ring-ref", "%u", &val);
869 if (err < 0)
870 goto done;
871
872 ring_ref = val;
873
874 err = xenbus_scanf(XBT_NIL, dev->otherend,
875 "event-channel-ctrl", "%u", &val);
876 if (err < 0) {
877 xenbus_dev_fatal(dev, err,
878 "reading %s/event-channel-ctrl",
879 dev->otherend);
880 goto fail;
881 }
882
883 evtchn = val;
884
885 err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
886 if (err) {
887 xenbus_dev_fatal(dev, err,
888 "mapping shared-frame %u port %u",
889 ring_ref, evtchn);
890 goto fail;
891 }
892
893done:
894 return 0;
895
896fail:
897 return err;
898}
899
900static void connect(struct backend_info *be)
901{
902 int err;
903 struct xenbus_device *dev = be->dev;
904 unsigned long credit_bytes, credit_usec;
905 unsigned int queue_index;
906 unsigned int requested_num_queues;
907 struct xenvif_queue *queue;
908
909
910
911
912 requested_num_queues = xenbus_read_unsigned(dev->otherend,
913 "multi-queue-num-queues", 1);
914 if (requested_num_queues > xenvif_max_queues) {
915
916 xenbus_dev_fatal(dev, -EINVAL,
917 "guest requested %u queues, exceeding the maximum of %u.",
918 requested_num_queues, xenvif_max_queues);
919 return;
920 }
921
922 err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
923 if (err) {
924 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
925 return;
926 }
927
928 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
929 xen_unregister_watchers(be->vif);
930 xen_register_watchers(dev, be->vif);
931 read_xenbus_vif_flags(be);
932
933 err = connect_ctrl_ring(be);
934 if (err) {
935 xenbus_dev_fatal(dev, err, "connecting control ring");
936 return;
937 }
938
939
940 be->vif->queues = vzalloc(array_size(requested_num_queues,
941 sizeof(struct xenvif_queue)));
942 if (!be->vif->queues) {
943 xenbus_dev_fatal(dev, -ENOMEM,
944 "allocating queues");
945 return;
946 }
947
948 be->vif->num_queues = requested_num_queues;
949 be->vif->stalled_queues = requested_num_queues;
950
951 for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
952 queue = &be->vif->queues[queue_index];
953 queue->vif = be->vif;
954 queue->id = queue_index;
955 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
956 be->vif->dev->name, queue->id);
957
958 err = xenvif_init_queue(queue);
959 if (err) {
960
961
962
963
964
965
966 be->vif->num_queues = queue_index;
967 goto err;
968 }
969
970 queue->credit_bytes = credit_bytes;
971 queue->remaining_credit = credit_bytes;
972 queue->credit_usec = credit_usec;
973
974 err = connect_data_rings(be, queue);
975 if (err) {
976
977
978
979
980
981 xenvif_deinit_queue(queue);
982 be->vif->num_queues = queue_index;
983 goto err;
984 }
985 }
986
987#ifdef CONFIG_DEBUG_FS
988 xenvif_debugfs_addif(be->vif);
989#endif
990
991
992
993
994 rtnl_lock();
995 netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
996 netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
997 rtnl_unlock();
998
999 xenvif_carrier_on(be->vif);
1000
1001 unregister_hotplug_status_watch(be);
1002 err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
1003 hotplug_status_changed,
1004 "%s/%s", dev->nodename, "hotplug-status");
1005 if (!err)
1006 be->have_hotplug_status_watch = 1;
1007
1008 netif_tx_wake_all_queues(be->vif->dev);
1009
1010 return;
1011
1012err:
1013 if (be->vif->num_queues > 0)
1014 xenvif_disconnect_data(be->vif);
1015 for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
1016 xenvif_deinit_queue(&be->vif->queues[queue_index]);
1017 vfree(be->vif->queues);
1018 be->vif->queues = NULL;
1019 be->vif->num_queues = 0;
1020 xenvif_disconnect_ctrl(be->vif);
1021 return;
1022}
1023
1024
1025static int connect_data_rings(struct backend_info *be,
1026 struct xenvif_queue *queue)
1027{
1028 struct xenbus_device *dev = be->dev;
1029 unsigned int num_queues = queue->vif->num_queues;
1030 unsigned long tx_ring_ref, rx_ring_ref;
1031 unsigned int tx_evtchn, rx_evtchn;
1032 int err;
1033 char *xspath;
1034 size_t xspathsize;
1035 const size_t xenstore_path_ext_size = 11;
1036
1037
1038
1039
1040
1041
1042
1043 if (num_queues == 1) {
1044 xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
1045 if (!xspath) {
1046 xenbus_dev_fatal(dev, -ENOMEM,
1047 "reading ring references");
1048 return -ENOMEM;
1049 }
1050 strcpy(xspath, dev->otherend);
1051 } else {
1052 xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
1053 xspath = kzalloc(xspathsize, GFP_KERNEL);
1054 if (!xspath) {
1055 xenbus_dev_fatal(dev, -ENOMEM,
1056 "reading ring references");
1057 return -ENOMEM;
1058 }
1059 snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
1060 queue->id);
1061 }
1062
1063 err = xenbus_gather(XBT_NIL, xspath,
1064 "tx-ring-ref", "%lu", &tx_ring_ref,
1065 "rx-ring-ref", "%lu", &rx_ring_ref, NULL);
1066 if (err) {
1067 xenbus_dev_fatal(dev, err,
1068 "reading %s/ring-ref",
1069 xspath);
1070 goto err;
1071 }
1072
1073
1074 err = xenbus_gather(XBT_NIL, xspath,
1075 "event-channel-tx", "%u", &tx_evtchn,
1076 "event-channel-rx", "%u", &rx_evtchn, NULL);
1077 if (err < 0) {
1078 err = xenbus_scanf(XBT_NIL, xspath,
1079 "event-channel", "%u", &tx_evtchn);
1080 if (err < 0) {
1081 xenbus_dev_fatal(dev, err,
1082 "reading %s/event-channel(-tx/rx)",
1083 xspath);
1084 goto err;
1085 }
1086 rx_evtchn = tx_evtchn;
1087 }
1088
1089
1090 err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
1091 tx_evtchn, rx_evtchn);
1092 if (err) {
1093 xenbus_dev_fatal(dev, err,
1094 "mapping shared-frames %lu/%lu port tx %u rx %u",
1095 tx_ring_ref, rx_ring_ref,
1096 tx_evtchn, rx_evtchn);
1097 goto err;
1098 }
1099
1100 err = 0;
1101err:
1102 kfree(xspath);
1103 return err;
1104}
1105
1106static int read_xenbus_vif_flags(struct backend_info *be)
1107{
1108 struct xenvif *vif = be->vif;
1109 struct xenbus_device *dev = be->dev;
1110 unsigned int rx_copy;
1111 int err;
1112
1113 err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
1114 &rx_copy);
1115 if (err == -ENOENT) {
1116 err = 0;
1117 rx_copy = 0;
1118 }
1119 if (err < 0) {
1120 xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
1121 dev->otherend);
1122 return err;
1123 }
1124 if (!rx_copy)
1125 return -EOPNOTSUPP;
1126
1127 if (!xenbus_read_unsigned(dev->otherend, "feature-rx-notify", 0)) {
1128
1129
1130
1131
1132 be->vif->drain_timeout = msecs_to_jiffies(30);
1133 be->vif->stall_timeout = 0;
1134 }
1135
1136 vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0);
1137
1138 vif->gso_mask = 0;
1139
1140 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0))
1141 vif->gso_mask |= GSO_BIT(TCPV4);
1142
1143 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv6", 0))
1144 vif->gso_mask |= GSO_BIT(TCPV6);
1145
1146 vif->ip_csum = !xenbus_read_unsigned(dev->otherend,
1147 "feature-no-csum-offload", 0);
1148
1149 vif->ipv6_csum = !!xenbus_read_unsigned(dev->otherend,
1150 "feature-ipv6-csum-offload", 0);
1151
1152 return 0;
1153}
1154
1155static const struct xenbus_device_id netback_ids[] = {
1156 { "vif" },
1157 { "" }
1158};
1159
1160static struct xenbus_driver netback_driver = {
1161 .ids = netback_ids,
1162 .probe = netback_probe,
1163 .remove = netback_remove,
1164 .uevent = netback_uevent,
1165 .otherend_changed = frontend_changed,
1166};
1167
1168int xenvif_xenbus_init(void)
1169{
1170 return xenbus_register_backend(&netback_driver);
1171}
1172
1173void xenvif_xenbus_fini(void)
1174{
1175 return xenbus_unregister_driver(&netback_driver);
1176}
1177
