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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 int i;
174
175 vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name,
176 xen_netback_dbg_root);
177 for (i = 0; i < vif->num_queues; ++i) {
178 char filename[sizeof("io_ring_q") + 4];
179
180 snprintf(filename, sizeof(filename), "io_ring_q%d", i);
181 debugfs_create_file(filename, 0600, vif->xenvif_dbg_root,
182 &vif->queues[i],
183 &xenvif_dbg_io_ring_ops_fops);
184 }
185
186 if (vif->ctrl_irq)
187 debugfs_create_file("ctrl", 0400, vif->xenvif_dbg_root, vif,
188 &xenvif_ctrl_fops);
189}
190
191static void xenvif_debugfs_delif(struct xenvif *vif)
192{
193 debugfs_remove_recursive(vif->xenvif_dbg_root);
194 vif->xenvif_dbg_root = NULL;
195}
196#endif
197
198
199
200
201
202
203static int netback_uevent(struct xenbus_device *xdev,
204 struct kobj_uevent_env *env)
205{
206 struct backend_info *be = dev_get_drvdata(&xdev->dev);
207
208 if (!be)
209 return 0;
210
211 if (add_uevent_var(env, "script=%s", be->hotplug_script))
212 return -ENOMEM;
213
214 if (!be->vif)
215 return 0;
216
217 return add_uevent_var(env, "vif=%s", be->vif->dev->name);
218}
219
220
221static int backend_create_xenvif(struct backend_info *be)
222{
223 int err;
224 long handle;
225 struct xenbus_device *dev = be->dev;
226 struct xenvif *vif;
227
228 if (be->vif != NULL)
229 return 0;
230
231 err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
232 if (err != 1) {
233 xenbus_dev_fatal(dev, err, "reading handle");
234 return (err < 0) ? err : -EINVAL;
235 }
236
237 vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
238 if (IS_ERR(vif)) {
239 err = PTR_ERR(vif);
240 xenbus_dev_fatal(dev, err, "creating interface");
241 return err;
242 }
243 be->vif = vif;
244 vif->be = be;
245
246 kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
247 return 0;
248}
249
250static void backend_disconnect(struct backend_info *be)
251{
252 struct xenvif *vif = be->vif;
253
254 if (vif) {
255 unsigned int num_queues = vif->num_queues;
256 unsigned int queue_index;
257
258 xen_unregister_watchers(vif);
259 xenbus_rm(XBT_NIL, be->dev->nodename, "hotplug-status");
260#ifdef CONFIG_DEBUG_FS
261 xenvif_debugfs_delif(vif);
262#endif
263 xenvif_disconnect_data(vif);
264
265
266
267
268 vif->num_queues = 0;
269 synchronize_net();
270
271 for (queue_index = 0; queue_index < num_queues; ++queue_index)
272 xenvif_deinit_queue(&vif->queues[queue_index]);
273
274 vfree(vif->queues);
275 vif->queues = NULL;
276
277 xenvif_disconnect_ctrl(vif);
278 }
279}
280
281static void backend_connect(struct backend_info *be)
282{
283 if (be->vif)
284 connect(be);
285}
286
287static inline void backend_switch_state(struct backend_info *be,
288 enum xenbus_state state)
289{
290 struct xenbus_device *dev = be->dev;
291
292 pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state));
293 be->state = state;
294
295
296
297
298 if (!be->have_hotplug_status_watch)
299 xenbus_switch_state(dev, state);
300}
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321
322static void set_backend_state(struct backend_info *be,
323 enum xenbus_state state)
324{
325 while (be->state != state) {
326 switch (be->state) {
327 case XenbusStateInitialising:
328 switch (state) {
329 case XenbusStateInitWait:
330 case XenbusStateConnected:
331 case XenbusStateClosing:
332 backend_switch_state(be, XenbusStateInitWait);
333 break;
334 case XenbusStateClosed:
335 backend_switch_state(be, XenbusStateClosed);
336 break;
337 default:
338 BUG();
339 }
340 break;
341 case XenbusStateClosed:
342 switch (state) {
343 case XenbusStateInitWait:
344 case XenbusStateConnected:
345 backend_switch_state(be, XenbusStateInitWait);
346 break;
347 case XenbusStateClosing:
348 backend_switch_state(be, XenbusStateClosing);
349 break;
350 default:
351 BUG();
352 }
353 break;
354 case XenbusStateInitWait:
355 switch (state) {
356 case XenbusStateConnected:
357 backend_connect(be);
358 backend_switch_state(be, XenbusStateConnected);
359 break;
360 case XenbusStateClosing:
361 case XenbusStateClosed:
362 backend_switch_state(be, XenbusStateClosing);
363 break;
364 default:
365 BUG();
366 }
367 break;
368 case XenbusStateConnected:
369 switch (state) {
370 case XenbusStateInitWait:
371 case XenbusStateClosing:
372 case XenbusStateClosed:
373 backend_disconnect(be);
374 backend_switch_state(be, XenbusStateClosing);
375 break;
376 default:
377 BUG();
378 }
379 break;
380 case XenbusStateClosing:
381 switch (state) {
382 case XenbusStateInitWait:
383 case XenbusStateConnected:
384 case XenbusStateClosed:
385 backend_switch_state(be, XenbusStateClosed);
386 break;
387 default:
388 BUG();
389 }
390 break;
391 default:
392 BUG();
393 }
394 }
395}
396
397static void read_xenbus_frontend_xdp(struct backend_info *be,
398 struct xenbus_device *dev)
399{
400 struct xenvif *vif = be->vif;
401 u16 headroom;
402 int err;
403
404 err = xenbus_scanf(XBT_NIL, dev->otherend,
405 "xdp-headroom", "%hu", &headroom);
406 if (err != 1) {
407 vif->xdp_headroom = 0;
408 return;
409 }
410 if (headroom > XEN_NETIF_MAX_XDP_HEADROOM)
411 headroom = XEN_NETIF_MAX_XDP_HEADROOM;
412 vif->xdp_headroom = headroom;
413}
414
415
416
417
418static void frontend_changed(struct xenbus_device *dev,
419 enum xenbus_state frontend_state)
420{
421 struct backend_info *be = dev_get_drvdata(&dev->dev);
422
423 pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state));
424
425 be->frontend_state = frontend_state;
426
427 switch (frontend_state) {
428 case XenbusStateInitialising:
429 set_backend_state(be, XenbusStateInitWait);
430 break;
431
432 case XenbusStateInitialised:
433 break;
434
435 case XenbusStateConnected:
436 set_backend_state(be, XenbusStateConnected);
437 break;
438
439 case XenbusStateReconfiguring:
440 read_xenbus_frontend_xdp(be, dev);
441 xenbus_switch_state(dev, XenbusStateReconfigured);
442 break;
443
444 case XenbusStateClosing:
445 set_backend_state(be, XenbusStateClosing);
446 break;
447
448 case XenbusStateClosed:
449 set_backend_state(be, XenbusStateClosed);
450 if (xenbus_dev_is_online(dev))
451 break;
452 fallthrough;
453 case XenbusStateUnknown:
454 set_backend_state(be, XenbusStateClosed);
455 device_unregister(&dev->dev);
456 break;
457
458 default:
459 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
460 frontend_state);
461 break;
462 }
463}
464
465
466static void xen_net_read_rate(struct xenbus_device *dev,
467 unsigned long *bytes, unsigned long *usec)
468{
469 char *s, *e;
470 unsigned long b, u;
471 char *ratestr;
472
473
474 *bytes = ~0UL;
475 *usec = 0;
476
477 ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
478 if (IS_ERR(ratestr))
479 return;
480
481 s = ratestr;
482 b = simple_strtoul(s, &e, 10);
483 if ((s == e) || (*e != ','))
484 goto fail;
485
486 s = e + 1;
487 u = simple_strtoul(s, &e, 10);
488 if ((s == e) || (*e != '\0'))
489 goto fail;
490
491 *bytes = b;
492 *usec = u;
493
494 kfree(ratestr);
495 return;
496
497 fail:
498 pr_warn("Failed to parse network rate limit. Traffic unlimited.\n");
499 kfree(ratestr);
500}
501
502static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
503{
504 char *s, *e, *macstr;
505 int i;
506
507 macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
508 if (IS_ERR(macstr))
509 return PTR_ERR(macstr);
510
511 for (i = 0; i < ETH_ALEN; i++) {
512 mac[i] = simple_strtoul(s, &e, 16);
513 if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
514 kfree(macstr);
515 return -ENOENT;
516 }
517 s = e+1;
518 }
519
520 kfree(macstr);
521 return 0;
522}
523
524static void xen_net_rate_changed(struct xenbus_watch *watch,
525 const char *path, const char *token)
526{
527 struct xenvif *vif = container_of(watch, struct xenvif, credit_watch);
528 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
529 unsigned long credit_bytes;
530 unsigned long credit_usec;
531 unsigned int queue_index;
532
533 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
534 for (queue_index = 0; queue_index < vif->num_queues; queue_index++) {
535 struct xenvif_queue *queue = &vif->queues[queue_index];
536
537 queue->credit_bytes = credit_bytes;
538 queue->credit_usec = credit_usec;
539 if (!mod_timer_pending(&queue->credit_timeout, jiffies) &&
540 queue->remaining_credit > queue->credit_bytes) {
541 queue->remaining_credit = queue->credit_bytes;
542 }
543 }
544}
545
546static int xen_register_credit_watch(struct xenbus_device *dev,
547 struct xenvif *vif)
548{
549 int err = 0;
550 char *node;
551 unsigned maxlen = strlen(dev->nodename) + sizeof("/rate");
552
553 if (vif->credit_watch.node)
554 return -EADDRINUSE;
555
556 node = kmalloc(maxlen, GFP_KERNEL);
557 if (!node)
558 return -ENOMEM;
559 snprintf(node, maxlen, "%s/rate", dev->nodename);
560 vif->credit_watch.node = node;
561 vif->credit_watch.will_handle = NULL;
562 vif->credit_watch.callback = xen_net_rate_changed;
563 err = register_xenbus_watch(&vif->credit_watch);
564 if (err) {
565 pr_err("Failed to set watcher %s\n", vif->credit_watch.node);
566 kfree(node);
567 vif->credit_watch.node = NULL;
568 vif->credit_watch.will_handle = NULL;
569 vif->credit_watch.callback = NULL;
570 }
571 return err;
572}
573
574static void xen_unregister_credit_watch(struct xenvif *vif)
575{
576 if (vif->credit_watch.node) {
577 unregister_xenbus_watch(&vif->credit_watch);
578 kfree(vif->credit_watch.node);
579 vif->credit_watch.node = NULL;
580 }
581}
582
583static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
584 const char *path, const char *token)
585{
586 struct xenvif *vif = container_of(watch, struct xenvif,
587 mcast_ctrl_watch);
588 struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
589
590 vif->multicast_control = !!xenbus_read_unsigned(dev->otherend,
591 "request-multicast-control", 0);
592}
593
594static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
595 struct xenvif *vif)
596{
597 int err = 0;
598 char *node;
599 unsigned maxlen = strlen(dev->otherend) +
600 sizeof("/request-multicast-control");
601
602 if (vif->mcast_ctrl_watch.node) {
603 pr_err_ratelimited("Watch is already registered\n");
604 return -EADDRINUSE;
605 }
606
607 node = kmalloc(maxlen, GFP_KERNEL);
608 if (!node) {
609 pr_err("Failed to allocate memory for watch\n");
610 return -ENOMEM;
611 }
612 snprintf(node, maxlen, "%s/request-multicast-control",
613 dev->otherend);
614 vif->mcast_ctrl_watch.node = node;
615 vif->mcast_ctrl_watch.will_handle = NULL;
616 vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
617 err = register_xenbus_watch(&vif->mcast_ctrl_watch);
618 if (err) {
619 pr_err("Failed to set watcher %s\n",
620 vif->mcast_ctrl_watch.node);
621 kfree(node);
622 vif->mcast_ctrl_watch.node = NULL;
623 vif->mcast_ctrl_watch.will_handle = NULL;
624 vif->mcast_ctrl_watch.callback = NULL;
625 }
626 return err;
627}
628
629static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
630{
631 if (vif->mcast_ctrl_watch.node) {
632 unregister_xenbus_watch(&vif->mcast_ctrl_watch);
633 kfree(vif->mcast_ctrl_watch.node);
634 vif->mcast_ctrl_watch.node = NULL;
635 }
636}
637
638static void xen_register_watchers(struct xenbus_device *dev,
639 struct xenvif *vif)
640{
641 xen_register_credit_watch(dev, vif);
642 xen_register_mcast_ctrl_watch(dev, vif);
643}
644
645static void xen_unregister_watchers(struct xenvif *vif)
646{
647 xen_unregister_mcast_ctrl_watch(vif);
648 xen_unregister_credit_watch(vif);
649}
650
651static void unregister_hotplug_status_watch(struct backend_info *be)
652{
653 if (be->have_hotplug_status_watch) {
654 unregister_xenbus_watch(&be->hotplug_status_watch);
655 kfree(be->hotplug_status_watch.node);
656 }
657 be->have_hotplug_status_watch = 0;
658}
659
660static void hotplug_status_changed(struct xenbus_watch *watch,
661 const char *path,
662 const char *token)
663{
664 struct backend_info *be = container_of(watch,
665 struct backend_info,
666 hotplug_status_watch);
667 char *str;
668 unsigned int len;
669
670 str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len);
671 if (IS_ERR(str))
672 return;
673 if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) {
674
675 xenbus_switch_state(be->dev, be->state);
676
677
678 unregister_hotplug_status_watch(be);
679 }
680 kfree(str);
681}
682
683static int connect_ctrl_ring(struct backend_info *be)
684{
685 struct xenbus_device *dev = be->dev;
686 struct xenvif *vif = be->vif;
687 unsigned int val;
688 grant_ref_t ring_ref;
689 unsigned int evtchn;
690 int err;
691
692 err = xenbus_scanf(XBT_NIL, dev->otherend,
693 "ctrl-ring-ref", "%u", &val);
694 if (err < 0)
695 goto done;
696
697 ring_ref = val;
698
699 err = xenbus_scanf(XBT_NIL, dev->otherend,
700 "event-channel-ctrl", "%u", &val);
701 if (err < 0) {
702 xenbus_dev_fatal(dev, err,
703 "reading %s/event-channel-ctrl",
704 dev->otherend);
705 goto fail;
706 }
707
708 evtchn = val;
709
710 err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
711 if (err) {
712 xenbus_dev_fatal(dev, err,
713 "mapping shared-frame %u port %u",
714 ring_ref, evtchn);
715 goto fail;
716 }
717
718done:
719 return 0;
720
721fail:
722 return err;
723}
724
725static void connect(struct backend_info *be)
726{
727 int err;
728 struct xenbus_device *dev = be->dev;
729 unsigned long credit_bytes, credit_usec;
730 unsigned int queue_index;
731 unsigned int requested_num_queues;
732 struct xenvif_queue *queue;
733
734
735
736
737 requested_num_queues = xenbus_read_unsigned(dev->otherend,
738 "multi-queue-num-queues", 1);
739 if (requested_num_queues > xenvif_max_queues) {
740
741 xenbus_dev_fatal(dev, -EINVAL,
742 "guest requested %u queues, exceeding the maximum of %u.",
743 requested_num_queues, xenvif_max_queues);
744 return;
745 }
746
747 err = xen_net_read_mac(dev, be->vif->fe_dev_addr);
748 if (err) {
749 xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
750 return;
751 }
752
753 xen_net_read_rate(dev, &credit_bytes, &credit_usec);
754 xen_unregister_watchers(be->vif);
755 xen_register_watchers(dev, be->vif);
756 read_xenbus_vif_flags(be);
757
758 err = connect_ctrl_ring(be);
759 if (err) {
760 xenbus_dev_fatal(dev, err, "connecting control ring");
761 return;
762 }
763
764
765 be->vif->queues = vzalloc(array_size(requested_num_queues,
766 sizeof(struct xenvif_queue)));
767 if (!be->vif->queues) {
768 xenbus_dev_fatal(dev, -ENOMEM,
769 "allocating queues");
770 return;
771 }
772
773 be->vif->num_queues = requested_num_queues;
774 be->vif->stalled_queues = requested_num_queues;
775
776 for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) {
777 queue = &be->vif->queues[queue_index];
778 queue->vif = be->vif;
779 queue->id = queue_index;
780 snprintf(queue->name, sizeof(queue->name), "%s-q%u",
781 be->vif->dev->name, queue->id);
782
783 err = xenvif_init_queue(queue);
784 if (err) {
785
786
787
788
789
790
791 be->vif->num_queues = queue_index;
792 goto err;
793 }
794
795 queue->credit_bytes = credit_bytes;
796 queue->remaining_credit = credit_bytes;
797 queue->credit_usec = credit_usec;
798
799 err = connect_data_rings(be, queue);
800 if (err) {
801
802
803
804
805
806 xenvif_deinit_queue(queue);
807 be->vif->num_queues = queue_index;
808 goto err;
809 }
810 }
811
812#ifdef CONFIG_DEBUG_FS
813 xenvif_debugfs_addif(be->vif);
814#endif
815
816
817
818
819 rtnl_lock();
820 netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues);
821 netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues);
822 rtnl_unlock();
823
824 xenvif_carrier_on(be->vif);
825
826 unregister_hotplug_status_watch(be);
827 err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, NULL,
828 hotplug_status_changed,
829 "%s/%s", dev->nodename, "hotplug-status");
830 if (!err)
831 be->have_hotplug_status_watch = 1;
832
833 netif_tx_wake_all_queues(be->vif->dev);
834
835 return;
836
837err:
838 if (be->vif->num_queues > 0)
839 xenvif_disconnect_data(be->vif);
840 for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index)
841 xenvif_deinit_queue(&be->vif->queues[queue_index]);
842 vfree(be->vif->queues);
843 be->vif->queues = NULL;
844 be->vif->num_queues = 0;
845 xenvif_disconnect_ctrl(be->vif);
846 return;
847}
848
849
850static int connect_data_rings(struct backend_info *be,
851 struct xenvif_queue *queue)
852{
853 struct xenbus_device *dev = be->dev;
854 unsigned int num_queues = queue->vif->num_queues;
855 unsigned long tx_ring_ref, rx_ring_ref;
856 unsigned int tx_evtchn, rx_evtchn;
857 int err;
858 char *xspath;
859 size_t xspathsize;
860 const size_t xenstore_path_ext_size = 11;
861
862
863
864
865
866
867
868 if (num_queues == 1) {
869 xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL);
870 if (!xspath) {
871 xenbus_dev_fatal(dev, -ENOMEM,
872 "reading ring references");
873 return -ENOMEM;
874 }
875 strcpy(xspath, dev->otherend);
876 } else {
877 xspathsize = strlen(dev->otherend) + xenstore_path_ext_size;
878 xspath = kzalloc(xspathsize, GFP_KERNEL);
879 if (!xspath) {
880 xenbus_dev_fatal(dev, -ENOMEM,
881 "reading ring references");
882 return -ENOMEM;
883 }
884 snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend,
885 queue->id);
886 }
887
888 err = xenbus_gather(XBT_NIL, xspath,
889 "tx-ring-ref", "%lu", &tx_ring_ref,
890 "rx-ring-ref", "%lu", &rx_ring_ref, NULL);
891 if (err) {
892 xenbus_dev_fatal(dev, err,
893 "reading %s/ring-ref",
894 xspath);
895 goto err;
896 }
897
898
899 err = xenbus_gather(XBT_NIL, xspath,
900 "event-channel-tx", "%u", &tx_evtchn,
901 "event-channel-rx", "%u", &rx_evtchn, NULL);
902 if (err < 0) {
903 err = xenbus_scanf(XBT_NIL, xspath,
904 "event-channel", "%u", &tx_evtchn);
905 if (err < 0) {
906 xenbus_dev_fatal(dev, err,
907 "reading %s/event-channel(-tx/rx)",
908 xspath);
909 goto err;
910 }
911 rx_evtchn = tx_evtchn;
912 }
913
914
915 err = xenvif_connect_data(queue, tx_ring_ref, rx_ring_ref,
916 tx_evtchn, rx_evtchn);
917 if (err) {
918 xenbus_dev_fatal(dev, err,
919 "mapping shared-frames %lu/%lu port tx %u rx %u",
920 tx_ring_ref, rx_ring_ref,
921 tx_evtchn, rx_evtchn);
922 goto err;
923 }
924
925 err = 0;
926err:
927 kfree(xspath);
928 return err;
929}
930
931static int read_xenbus_vif_flags(struct backend_info *be)
932{
933 struct xenvif *vif = be->vif;
934 struct xenbus_device *dev = be->dev;
935 unsigned int rx_copy;
936 int err;
937
938 err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
939 &rx_copy);
940 if (err == -ENOENT) {
941 err = 0;
942 rx_copy = 0;
943 }
944 if (err < 0) {
945 xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
946 dev->otherend);
947 return err;
948 }
949 if (!rx_copy)
950 return -EOPNOTSUPP;
951
952 if (!xenbus_read_unsigned(dev->otherend, "feature-rx-notify", 0)) {
953
954
955
956
957 be->vif->drain_timeout = msecs_to_jiffies(30);
958 be->vif->stall_timeout = 0;
959 }
960
961 vif->can_sg = !!xenbus_read_unsigned(dev->otherend, "feature-sg", 0);
962
963 vif->gso_mask = 0;
964
965 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv4", 0))
966 vif->gso_mask |= GSO_BIT(TCPV4);
967
968 if (xenbus_read_unsigned(dev->otherend, "feature-gso-tcpv6", 0))
969 vif->gso_mask |= GSO_BIT(TCPV6);
970
971 vif->ip_csum = !xenbus_read_unsigned(dev->otherend,
972 "feature-no-csum-offload", 0);
973
974 vif->ipv6_csum = !!xenbus_read_unsigned(dev->otherend,
975 "feature-ipv6-csum-offload", 0);
976
977 read_xenbus_frontend_xdp(be, dev);
978
979 return 0;
980}
981
982static int netback_remove(struct xenbus_device *dev)
983{
984 struct backend_info *be = dev_get_drvdata(&dev->dev);
985
986 unregister_hotplug_status_watch(be);
987 if (be->vif) {
988 kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
989 backend_disconnect(be);
990 xenvif_free(be->vif);
991 be->vif = NULL;
992 }
993 kfree(be->hotplug_script);
994 kfree(be);
995 dev_set_drvdata(&dev->dev, NULL);
996 return 0;
997}
998
999
1000
1001
1002
1003static int netback_probe(struct xenbus_device *dev,
1004 const struct xenbus_device_id *id)
1005{
1006 const char *message;
1007 struct xenbus_transaction xbt;
1008 int err;
1009 int sg;
1010 const char *script;
1011 struct backend_info *be = kzalloc(sizeof(*be), GFP_KERNEL);
1012
1013 if (!be) {
1014 xenbus_dev_fatal(dev, -ENOMEM,
1015 "allocating backend structure");
1016 return -ENOMEM;
1017 }
1018
1019 be->dev = dev;
1020 dev_set_drvdata(&dev->dev, be);
1021
1022 sg = 1;
1023
1024 do {
1025 err = xenbus_transaction_start(&xbt);
1026 if (err) {
1027 xenbus_dev_fatal(dev, err, "starting transaction");
1028 goto fail;
1029 }
1030
1031 err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
1032 if (err) {
1033 message = "writing feature-sg";
1034 goto abort_transaction;
1035 }
1036
1037 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
1038 "%d", sg);
1039 if (err) {
1040 message = "writing feature-gso-tcpv4";
1041 goto abort_transaction;
1042 }
1043
1044 err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6",
1045 "%d", sg);
1046 if (err) {
1047 message = "writing feature-gso-tcpv6";
1048 goto abort_transaction;
1049 }
1050
1051
1052 err = xenbus_printf(xbt, dev->nodename,
1053 "feature-ipv6-csum-offload",
1054 "%d", 1);
1055 if (err) {
1056 message = "writing feature-ipv6-csum-offload";
1057 goto abort_transaction;
1058 }
1059
1060
1061 err = xenbus_printf(xbt, dev->nodename,
1062 "feature-rx-copy", "%d", 1);
1063 if (err) {
1064 message = "writing feature-rx-copy";
1065 goto abort_transaction;
1066 }
1067
1068
1069 err = xenbus_printf(xbt, dev->nodename,
1070 "feature-xdp-headroom", "%d",
1071 provides_xdp_headroom);
1072 if (err) {
1073 message = "writing feature-xdp-headroom";
1074 goto abort_transaction;
1075 }
1076
1077
1078
1079
1080 err = xenbus_printf(xbt, dev->nodename,
1081 "feature-rx-flip", "%d", 0);
1082 if (err) {
1083 message = "writing feature-rx-flip";
1084 goto abort_transaction;
1085 }
1086
1087
1088 err = xenbus_printf(xbt, dev->nodename,
1089 "feature-multicast-control", "%d", 1);
1090 if (err) {
1091 message = "writing feature-multicast-control";
1092 goto abort_transaction;
1093 }
1094
1095 err = xenbus_printf(xbt, dev->nodename,
1096 "feature-dynamic-multicast-control",
1097 "%d", 1);
1098 if (err) {
1099 message = "writing feature-dynamic-multicast-control";
1100 goto abort_transaction;
1101 }
1102
1103 err = xenbus_transaction_end(xbt, 0);
1104 } while (err == -EAGAIN);
1105
1106 if (err) {
1107 xenbus_dev_fatal(dev, err, "completing transaction");
1108 goto fail;
1109 }
1110
1111
1112
1113
1114 err = xenbus_printf(XBT_NIL, dev->nodename,
1115 "feature-split-event-channels",
1116 "%u", separate_tx_rx_irq);
1117 if (err)
1118 pr_debug("Error writing feature-split-event-channels\n");
1119
1120
1121 err = xenbus_printf(XBT_NIL, dev->nodename,
1122 "multi-queue-max-queues", "%u", xenvif_max_queues);
1123 if (err)
1124 pr_debug("Error writing multi-queue-max-queues\n");
1125
1126 err = xenbus_printf(XBT_NIL, dev->nodename,
1127 "feature-ctrl-ring",
1128 "%u", true);
1129 if (err)
1130 pr_debug("Error writing feature-ctrl-ring\n");
1131
1132 backend_switch_state(be, XenbusStateInitWait);
1133
1134 script = xenbus_read(XBT_NIL, dev->nodename, "script", NULL);
1135 if (IS_ERR(script)) {
1136 err = PTR_ERR(script);
1137 xenbus_dev_fatal(dev, err, "reading script");
1138 goto fail;
1139 }
1140
1141 be->hotplug_script = script;
1142
1143
1144 err = backend_create_xenvif(be);
1145 if (err)
1146 goto fail;
1147
1148 return 0;
1149
1150abort_transaction:
1151 xenbus_transaction_end(xbt, 1);
1152 xenbus_dev_fatal(dev, err, "%s", message);
1153fail:
1154 pr_debug("failed\n");
1155 netback_remove(dev);
1156 return err;
1157}
1158
1159static const struct xenbus_device_id netback_ids[] = {
1160 { "vif" },
1161 { "" }
1162};
1163
1164static struct xenbus_driver netback_driver = {
1165 .ids = netback_ids,
1166 .probe = netback_probe,
1167 .remove = netback_remove,
1168 .uevent = netback_uevent,
1169 .otherend_changed = frontend_changed,
1170 .allow_rebind = true,
1171};
1172
1173int xenvif_xenbus_init(void)
1174{
1175 return xenbus_register_backend(&netback_driver);
1176}
1177
1178void xenvif_xenbus_fini(void)
1179{
1180 return xenbus_unregister_driver(&netback_driver);
1181}
1182
