1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * USB Network driver infrastructure
4 * Copyright (C) 2000-2005 by David Brownell
5 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
6 */
7
8 /*
9 * This is a generic "USB networking" framework that works with several
10 * kinds of full and high speed networking devices: host-to-host cables,
11 * smart usb peripherals, and actual Ethernet adapters.
12 *
13 * These devices usually differ in terms of control protocols (if they
14 * even have one!) and sometimes they define new framing to wrap or batch
15 * Ethernet packets. Otherwise, they talk to USB pretty much the same,
16 * so interface (un)binding, endpoint I/O queues, fault handling, and other
17 * issues can usefully be addressed by this framework.
18 */
19
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/ctype.h>
25 #include <linux/ethtool.h>
26 #include <linux/workqueue.h>
27 #include <linux/mii.h>
28 #include <linux/usb.h>
29 #include <linux/usb/usbnet.h>
30 #include <linux/slab.h>
31 #include <linux/kernel.h>
32 #include <linux/pm_runtime.h>
33
34 /*-------------------------------------------------------------------------*/
35
36 /*
37 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
38 * Several dozen bytes of IPv4 data can fit in two such transactions.
39 * One maximum size Ethernet packet takes twenty four of them.
40 * For high speed, each frame comfortably fits almost 36 max size
41 * Ethernet packets (so queues should be bigger).
42 *
43 * The goal is to let the USB host controller be busy for 5msec or
44 * more before an irq is required, under load. Jumbograms change
45 * the equation.
46 */
47 #define MAX_QUEUE_MEMORY (60 * 1518)
48 #define RX_QLEN(dev) ((dev)->rx_qlen)
49 #define TX_QLEN(dev) ((dev)->tx_qlen)
50
51 // reawaken network queue this soon after stopping; else watchdog barks
52 #define TX_TIMEOUT_JIFFIES (5*HZ)
53
54 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
55 * us (it polls at HZ/4 usually) before we report too many false errors.
56 */
57 #define THROTTLE_JIFFIES (HZ/8)
58
59 // between wakeups
60 #define UNLINK_TIMEOUT_MS 3
61
62 /*-------------------------------------------------------------------------*/
63
64 /* use ethtool to change the level for any given device */
65 static int msg_level = -1;
66 module_param (msg_level, int, 0);
67 MODULE_PARM_DESC (msg_level, "Override default message level");
68
69 /*-------------------------------------------------------------------------*/
70
71 static const char * const usbnet_event_names[] = {
72 [EVENT_TX_HALT] = "EVENT_TX_HALT",
73 [EVENT_RX_HALT] = "EVENT_RX_HALT",
74 [EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
75 [EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
76 [EVENT_LINK_RESET] = "EVENT_LINK_RESET",
77 [EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
78 [EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
79 [EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
80 [EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
81 [EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
82 [EVENT_RX_KILL] = "EVENT_RX_KILL",
83 [EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
84 [EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
85 [EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
86 };
87
88 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)89 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
90 {
91 int tmp;
92 struct usb_host_interface *alt = NULL;
93 struct usb_host_endpoint *in = NULL, *out = NULL;
94 struct usb_host_endpoint *status = NULL;
95
96 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
97 unsigned ep;
98
99 in = out = status = NULL;
100 alt = intf->altsetting + tmp;
101
102 /* take the first altsetting with in-bulk + out-bulk;
103 * remember any status endpoint, just in case;
104 * ignore other endpoints and altsettings.
105 */
106 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
107 struct usb_host_endpoint *e;
108 int intr = 0;
109
110 e = alt->endpoint + ep;
111
112 /* ignore endpoints which cannot transfer data */
113 if (!usb_endpoint_maxp(&e->desc))
114 continue;
115
116 switch (e->desc.bmAttributes) {
117 case USB_ENDPOINT_XFER_INT:
118 if (!usb_endpoint_dir_in(&e->desc))
119 continue;
120 intr = 1;
121 fallthrough;
122 case USB_ENDPOINT_XFER_BULK:
123 break;
124 default:
125 continue;
126 }
127 if (usb_endpoint_dir_in(&e->desc)) {
128 if (!intr && !in)
129 in = e;
130 else if (intr && !status)
131 status = e;
132 } else {
133 if (!out)
134 out = e;
135 }
136 }
137 if (in && out)
138 break;
139 }
140 if (!alt || !in || !out)
141 return -EINVAL;
142
143 if (alt->desc.bAlternateSetting != 0 ||
144 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
145 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
146 alt->desc.bAlternateSetting);
147 if (tmp < 0)
148 return tmp;
149 }
150
151 dev->in = usb_rcvbulkpipe (dev->udev,
152 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
153 dev->out = usb_sndbulkpipe (dev->udev,
154 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
155 dev->status = status;
156 return 0;
157 }
158 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
159
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)160 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
161 {
162 u8 addr[ETH_ALEN];
163 int tmp = -1, ret;
164 unsigned char buf [13];
165
166 ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
167 if (ret == 12)
168 tmp = hex2bin(addr, buf, 6);
169 if (tmp < 0) {
170 dev_dbg(&dev->udev->dev,
171 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
172 if (ret >= 0)
173 ret = -EINVAL;
174 return ret;
175 }
176 eth_hw_addr_set(dev->net, addr);
177 return 0;
178 }
179 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
180
intr_complete(struct urb * urb)181 static void intr_complete (struct urb *urb)
182 {
183 struct usbnet *dev = urb->context;
184 int status = urb->status;
185
186 switch (status) {
187 /* success */
188 case 0:
189 dev->driver_info->status(dev, urb);
190 break;
191
192 /* software-driven interface shutdown */
193 case -ENOENT: /* urb killed */
194 case -ESHUTDOWN: /* hardware gone */
195 netif_dbg(dev, ifdown, dev->net,
196 "intr shutdown, code %d\n", status);
197 return;
198
199 /* NOTE: not throttling like RX/TX, since this endpoint
200 * already polls infrequently
201 */
202 default:
203 netdev_dbg(dev->net, "intr status %d\n", status);
204 break;
205 }
206
207 status = usb_submit_urb (urb, GFP_ATOMIC);
208 if (status != 0)
209 netif_err(dev, timer, dev->net,
210 "intr resubmit --> %d\n", status);
211 }
212
init_status(struct usbnet * dev,struct usb_interface * intf)213 static int init_status (struct usbnet *dev, struct usb_interface *intf)
214 {
215 char *buf = NULL;
216 unsigned pipe = 0;
217 unsigned maxp;
218 unsigned period;
219
220 if (!dev->driver_info->status)
221 return 0;
222
223 pipe = usb_rcvintpipe (dev->udev,
224 dev->status->desc.bEndpointAddress
225 & USB_ENDPOINT_NUMBER_MASK);
226 maxp = usb_maxpacket(dev->udev, pipe);
227
228 /* avoid 1 msec chatter: min 8 msec poll rate */
229 period = max ((int) dev->status->desc.bInterval,
230 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
231
232 buf = kmalloc (maxp, GFP_KERNEL);
233 if (buf) {
234 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
235 if (!dev->interrupt) {
236 kfree (buf);
237 return -ENOMEM;
238 } else {
239 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
240 buf, maxp, intr_complete, dev, period);
241 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
242 dev_dbg(&intf->dev,
243 "status ep%din, %d bytes period %d\n",
244 usb_pipeendpoint(pipe), maxp, period);
245 }
246 }
247 return 0;
248 }
249
250 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)251 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
252 {
253 int ret = 0;
254
255 WARN_ON_ONCE(dev->interrupt == NULL);
256 if (dev->interrupt) {
257 mutex_lock(&dev->interrupt_mutex);
258
259 if (++dev->interrupt_count == 1)
260 ret = usb_submit_urb(dev->interrupt, mem_flags);
261
262 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
263 dev->interrupt_count);
264 mutex_unlock(&dev->interrupt_mutex);
265 }
266 return ret;
267 }
268 EXPORT_SYMBOL_GPL(usbnet_status_start);
269
270 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)271 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
272 {
273 int ret = 0;
274
275 mutex_lock(&dev->interrupt_mutex);
276 if (dev->interrupt_count) {
277 ret = usb_submit_urb(dev->interrupt, mem_flags);
278 dev_dbg(&dev->udev->dev,
279 "submitted interrupt URB for resume\n");
280 }
281 mutex_unlock(&dev->interrupt_mutex);
282 return ret;
283 }
284
285 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)286 void usbnet_status_stop(struct usbnet *dev)
287 {
288 if (dev->interrupt) {
289 mutex_lock(&dev->interrupt_mutex);
290 WARN_ON(dev->interrupt_count == 0);
291
292 if (dev->interrupt_count && --dev->interrupt_count == 0)
293 usb_kill_urb(dev->interrupt);
294
295 dev_dbg(&dev->udev->dev,
296 "decremented interrupt URB count to %d\n",
297 dev->interrupt_count);
298 mutex_unlock(&dev->interrupt_mutex);
299 }
300 }
301 EXPORT_SYMBOL_GPL(usbnet_status_stop);
302
303 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)304 static void __usbnet_status_stop_force(struct usbnet *dev)
305 {
306 if (dev->interrupt) {
307 mutex_lock(&dev->interrupt_mutex);
308 usb_kill_urb(dev->interrupt);
309 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
310 mutex_unlock(&dev->interrupt_mutex);
311 }
312 }
313
314 /* Passes this packet up the stack, updating its accounting.
315 * Some link protocols batch packets, so their rx_fixup paths
316 * can return clones as well as just modify the original skb.
317 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)318 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
319 {
320 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
321 unsigned long flags;
322 int status;
323
324 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
325 skb_queue_tail(&dev->rxq_pause, skb);
326 return;
327 }
328
329 /* only update if unset to allow minidriver rx_fixup override */
330 if (skb->protocol == 0)
331 skb->protocol = eth_type_trans (skb, dev->net);
332
333 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
334 u64_stats_inc(&stats64->rx_packets);
335 u64_stats_add(&stats64->rx_bytes, skb->len);
336 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
337
338 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
339 skb->len + sizeof (struct ethhdr), skb->protocol);
340 memset (skb->cb, 0, sizeof (struct skb_data));
341
342 if (skb_defer_rx_timestamp(skb))
343 return;
344
345 status = netif_rx (skb);
346 if (status != NET_RX_SUCCESS)
347 netif_dbg(dev, rx_err, dev->net,
348 "netif_rx status %d\n", status);
349 }
350 EXPORT_SYMBOL_GPL(usbnet_skb_return);
351
352 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)353 void usbnet_update_max_qlen(struct usbnet *dev)
354 {
355 enum usb_device_speed speed = dev->udev->speed;
356
357 if (!dev->rx_urb_size || !dev->hard_mtu)
358 goto insanity;
359 switch (speed) {
360 case USB_SPEED_HIGH:
361 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
362 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
363 break;
364 case USB_SPEED_SUPER:
365 case USB_SPEED_SUPER_PLUS:
366 /*
367 * Not take default 5ms qlen for super speed HC to
368 * save memory, and iperf tests show 2.5ms qlen can
369 * work well
370 */
371 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
372 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
373 break;
374 default:
375 insanity:
376 dev->rx_qlen = dev->tx_qlen = 4;
377 }
378 }
379 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
380
381
382 /*-------------------------------------------------------------------------
383 *
384 * Network Device Driver (peer link to "Host Device", from USB host)
385 *
386 *-------------------------------------------------------------------------*/
387
usbnet_change_mtu(struct net_device * net,int new_mtu)388 int usbnet_change_mtu (struct net_device *net, int new_mtu)
389 {
390 struct usbnet *dev = netdev_priv(net);
391 int ll_mtu = new_mtu + net->hard_header_len;
392 int old_hard_mtu = dev->hard_mtu;
393 int old_rx_urb_size = dev->rx_urb_size;
394
395 // no second zero-length packet read wanted after mtu-sized packets
396 if ((ll_mtu % dev->maxpacket) == 0)
397 return -EDOM;
398 net->mtu = new_mtu;
399
400 dev->hard_mtu = net->mtu + net->hard_header_len;
401 if (dev->rx_urb_size == old_hard_mtu) {
402 dev->rx_urb_size = dev->hard_mtu;
403 if (dev->rx_urb_size > old_rx_urb_size) {
404 usbnet_pause_rx(dev);
405 usbnet_unlink_rx_urbs(dev);
406 usbnet_resume_rx(dev);
407 }
408 }
409
410 /* max qlen depend on hard_mtu and rx_urb_size */
411 usbnet_update_max_qlen(dev);
412
413 return 0;
414 }
415 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
416
417 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)418 static void __usbnet_queue_skb(struct sk_buff_head *list,
419 struct sk_buff *newsk, enum skb_state state)
420 {
421 struct skb_data *entry = (struct skb_data *) newsk->cb;
422
423 __skb_queue_tail(list, newsk);
424 entry->state = state;
425 }
426
427 /*-------------------------------------------------------------------------*/
428
429 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
430 * completion callbacks. 2.5 should have fixed those bugs...
431 */
432
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)433 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
434 struct sk_buff_head *list, enum skb_state state)
435 {
436 unsigned long flags;
437 enum skb_state old_state;
438 struct skb_data *entry = (struct skb_data *) skb->cb;
439
440 spin_lock_irqsave(&list->lock, flags);
441 old_state = entry->state;
442 entry->state = state;
443 __skb_unlink(skb, list);
444
445 /* defer_bh() is never called with list == &dev->done.
446 * spin_lock_nested() tells lockdep that it is OK to take
447 * dev->done.lock here with list->lock held.
448 */
449 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
450
451 __skb_queue_tail(&dev->done, skb);
452 if (dev->done.qlen == 1)
453 tasklet_schedule(&dev->bh);
454 spin_unlock(&dev->done.lock);
455 spin_unlock_irqrestore(&list->lock, flags);
456 return old_state;
457 }
458
459 /* some work can't be done in tasklets, so we use keventd
460 *
461 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
462 * but tasklet_schedule() doesn't. hope the failure is rare.
463 */
usbnet_defer_kevent(struct usbnet * dev,int work)464 void usbnet_defer_kevent (struct usbnet *dev, int work)
465 {
466 set_bit (work, &dev->flags);
467 if (!usbnet_going_away(dev)) {
468 if (!schedule_work(&dev->kevent))
469 netdev_dbg(dev->net,
470 "kevent %s may have been dropped\n",
471 usbnet_event_names[work]);
472 else
473 netdev_dbg(dev->net,
474 "kevent %s scheduled\n", usbnet_event_names[work]);
475 }
476 }
477 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
478
479 /*-------------------------------------------------------------------------*/
480
481 static void rx_complete (struct urb *urb);
482
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)483 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
484 {
485 struct sk_buff *skb;
486 struct skb_data *entry;
487 int retval = 0;
488 unsigned long lockflags;
489 size_t size = dev->rx_urb_size;
490
491 /* prevent rx skb allocation when error ratio is high */
492 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
493 usb_free_urb(urb);
494 return -ENOLINK;
495 }
496
497 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
498 skb = __netdev_alloc_skb(dev->net, size, flags);
499 else
500 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
501 if (!skb) {
502 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
503 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
504 usb_free_urb (urb);
505 return -ENOMEM;
506 }
507
508 entry = (struct skb_data *) skb->cb;
509 entry->urb = urb;
510 entry->dev = dev;
511 entry->length = 0;
512
513 usb_fill_bulk_urb (urb, dev->udev, dev->in,
514 skb->data, size, rx_complete, skb);
515
516 spin_lock_irqsave (&dev->rxq.lock, lockflags);
517
518 if (netif_running (dev->net) &&
519 netif_device_present (dev->net) &&
520 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
521 !test_bit (EVENT_RX_HALT, &dev->flags) &&
522 !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
523 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
524 case -EPIPE:
525 usbnet_defer_kevent (dev, EVENT_RX_HALT);
526 break;
527 case -ENOMEM:
528 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
529 break;
530 case -ENODEV:
531 netif_dbg(dev, ifdown, dev->net, "device gone\n");
532 netif_device_detach (dev->net);
533 break;
534 case -EHOSTUNREACH:
535 retval = -ENOLINK;
536 break;
537 default:
538 netif_dbg(dev, rx_err, dev->net,
539 "rx submit, %d\n", retval);
540 tasklet_schedule (&dev->bh);
541 break;
542 case 0:
543 if (!usbnet_going_away(dev))
544 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
545 }
546 } else {
547 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
548 retval = -ENOLINK;
549 }
550 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
551 if (retval) {
552 dev_kfree_skb_any (skb);
553 usb_free_urb (urb);
554 }
555 return retval;
556 }
557
558
559 /*-------------------------------------------------------------------------*/
560
rx_process(struct usbnet * dev,struct sk_buff * skb)561 static inline int rx_process(struct usbnet *dev, struct sk_buff *skb)
562 {
563 if (dev->driver_info->rx_fixup &&
564 !dev->driver_info->rx_fixup (dev, skb)) {
565 /* With RX_ASSEMBLE, rx_fixup() must update counters */
566 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
567 dev->net->stats.rx_errors++;
568 return -EPROTO;
569 }
570 // else network stack removes extra byte if we forced a short packet
571
572 /* all data was already cloned from skb inside the driver */
573 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
574 return -EALREADY;
575
576 if (skb->len < ETH_HLEN) {
577 dev->net->stats.rx_errors++;
578 dev->net->stats.rx_length_errors++;
579 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
580 return -EPROTO;
581 }
582
583 usbnet_skb_return(dev, skb);
584 return 0;
585 }
586
587 /*-------------------------------------------------------------------------*/
588
rx_complete(struct urb * urb)589 static void rx_complete (struct urb *urb)
590 {
591 struct sk_buff *skb = (struct sk_buff *) urb->context;
592 struct skb_data *entry = (struct skb_data *) skb->cb;
593 struct usbnet *dev = entry->dev;
594 int urb_status = urb->status;
595 enum skb_state state;
596
597 skb_put (skb, urb->actual_length);
598 state = rx_done;
599 entry->urb = NULL;
600
601 switch (urb_status) {
602 /* success */
603 case 0:
604 break;
605
606 /* stalls need manual reset. this is rare ... except that
607 * when going through USB 2.0 TTs, unplug appears this way.
608 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
609 * storm, recovering as needed.
610 */
611 case -EPIPE:
612 dev->net->stats.rx_errors++;
613 usbnet_defer_kevent (dev, EVENT_RX_HALT);
614 fallthrough;
615
616 /* software-driven interface shutdown */
617 case -ECONNRESET: /* async unlink */
618 case -ESHUTDOWN: /* hardware gone */
619 netif_dbg(dev, ifdown, dev->net,
620 "rx shutdown, code %d\n", urb_status);
621 goto block;
622
623 /* we get controller i/o faults during hub_wq disconnect() delays.
624 * throttle down resubmits, to avoid log floods; just temporarily,
625 * so we still recover when the fault isn't a hub_wq delay.
626 */
627 case -EPROTO:
628 case -ETIME:
629 case -EILSEQ:
630 dev->net->stats.rx_errors++;
631 if (!timer_pending (&dev->delay)) {
632 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
633 netif_dbg(dev, link, dev->net,
634 "rx throttle %d\n", urb_status);
635 }
636 block:
637 state = rx_cleanup;
638 entry->urb = urb;
639 urb = NULL;
640 break;
641
642 /* data overrun ... flush fifo? */
643 case -EOVERFLOW:
644 dev->net->stats.rx_over_errors++;
645 fallthrough;
646
647 default:
648 state = rx_cleanup;
649 dev->net->stats.rx_errors++;
650 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
651 break;
652 }
653
654 /* stop rx if packet error rate is high */
655 if (++dev->pkt_cnt > 30) {
656 dev->pkt_cnt = 0;
657 dev->pkt_err = 0;
658 } else {
659 if (state == rx_cleanup)
660 dev->pkt_err++;
661 if (dev->pkt_err > 20)
662 set_bit(EVENT_RX_KILL, &dev->flags);
663 }
664
665 state = defer_bh(dev, skb, &dev->rxq, state);
666
667 if (urb) {
668 if (netif_running (dev->net) &&
669 !test_bit (EVENT_RX_HALT, &dev->flags) &&
670 state != unlink_start) {
671 rx_submit (dev, urb, GFP_ATOMIC);
672 usb_mark_last_busy(dev->udev);
673 return;
674 }
675 usb_free_urb (urb);
676 }
677 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
678 }
679
680 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)681 void usbnet_pause_rx(struct usbnet *dev)
682 {
683 set_bit(EVENT_RX_PAUSED, &dev->flags);
684
685 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
686 }
687 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
688
usbnet_resume_rx(struct usbnet * dev)689 void usbnet_resume_rx(struct usbnet *dev)
690 {
691 struct sk_buff *skb;
692 int num = 0;
693
694 clear_bit(EVENT_RX_PAUSED, &dev->flags);
695
696 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
697 usbnet_skb_return(dev, skb);
698 num++;
699 }
700
701 tasklet_schedule(&dev->bh);
702
703 netif_dbg(dev, rx_status, dev->net,
704 "paused rx queue disabled, %d skbs requeued\n", num);
705 }
706 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
707
usbnet_purge_paused_rxq(struct usbnet * dev)708 void usbnet_purge_paused_rxq(struct usbnet *dev)
709 {
710 skb_queue_purge(&dev->rxq_pause);
711 }
712 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
713
714 /*-------------------------------------------------------------------------*/
715
716 // unlink pending rx/tx; completion handlers do all other cleanup
717
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)718 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
719 {
720 unsigned long flags;
721 struct sk_buff *skb;
722 int count = 0;
723
724 spin_lock_irqsave (&q->lock, flags);
725 while (!skb_queue_empty(q)) {
726 struct skb_data *entry;
727 struct urb *urb;
728 int retval;
729
730 skb_queue_walk(q, skb) {
731 entry = (struct skb_data *) skb->cb;
732 if (entry->state != unlink_start)
733 goto found;
734 }
735 break;
736 found:
737 entry->state = unlink_start;
738 urb = entry->urb;
739
740 /*
741 * Get reference count of the URB to avoid it to be
742 * freed during usb_unlink_urb, which may trigger
743 * use-after-free problem inside usb_unlink_urb since
744 * usb_unlink_urb is always racing with .complete
745 * handler(include defer_bh).
746 */
747 usb_get_urb(urb);
748 spin_unlock_irqrestore(&q->lock, flags);
749 // during some PM-driven resume scenarios,
750 // these (async) unlinks complete immediately
751 retval = usb_unlink_urb (urb);
752 if (retval != -EINPROGRESS && retval != 0)
753 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
754 else
755 count++;
756 usb_put_urb(urb);
757 spin_lock_irqsave(&q->lock, flags);
758 }
759 spin_unlock_irqrestore (&q->lock, flags);
760 return count;
761 }
762
763 // Flush all pending rx urbs
764 // minidrivers may need to do this when the MTU changes
765
usbnet_unlink_rx_urbs(struct usbnet * dev)766 void usbnet_unlink_rx_urbs(struct usbnet *dev)
767 {
768 if (netif_running(dev->net)) {
769 (void) unlink_urbs (dev, &dev->rxq);
770 tasklet_schedule(&dev->bh);
771 }
772 }
773 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
774
775 /*-------------------------------------------------------------------------*/
776
wait_skb_queue_empty(struct sk_buff_head * q)777 static void wait_skb_queue_empty(struct sk_buff_head *q)
778 {
779 unsigned long flags;
780
781 spin_lock_irqsave(&q->lock, flags);
782 while (!skb_queue_empty(q)) {
783 spin_unlock_irqrestore(&q->lock, flags);
784 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
785 set_current_state(TASK_UNINTERRUPTIBLE);
786 spin_lock_irqsave(&q->lock, flags);
787 }
788 spin_unlock_irqrestore(&q->lock, flags);
789 }
790
791 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)792 static void usbnet_terminate_urbs(struct usbnet *dev)
793 {
794 DECLARE_WAITQUEUE(wait, current);
795 int temp;
796
797 /* ensure there are no more active urbs */
798 add_wait_queue(&dev->wait, &wait);
799 set_current_state(TASK_UNINTERRUPTIBLE);
800 temp = unlink_urbs(dev, &dev->txq) +
801 unlink_urbs(dev, &dev->rxq);
802
803 /* maybe wait for deletions to finish. */
804 wait_skb_queue_empty(&dev->rxq);
805 wait_skb_queue_empty(&dev->txq);
806 wait_skb_queue_empty(&dev->done);
807 netif_dbg(dev, ifdown, dev->net,
808 "waited for %d urb completions\n", temp);
809 set_current_state(TASK_RUNNING);
810 remove_wait_queue(&dev->wait, &wait);
811 }
812
usbnet_stop(struct net_device * net)813 int usbnet_stop (struct net_device *net)
814 {
815 struct usbnet *dev = netdev_priv(net);
816 const struct driver_info *info = dev->driver_info;
817 int retval, pm, mpn;
818
819 clear_bit(EVENT_DEV_OPEN, &dev->flags);
820 netif_stop_queue (net);
821
822 netif_info(dev, ifdown, dev->net,
823 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
824 net->stats.rx_packets, net->stats.tx_packets,
825 net->stats.rx_errors, net->stats.tx_errors);
826
827 /* to not race resume */
828 pm = usb_autopm_get_interface(dev->intf);
829 /* allow minidriver to stop correctly (wireless devices to turn off
830 * radio etc) */
831 if (info->stop) {
832 retval = info->stop(dev);
833 if (retval < 0)
834 netif_info(dev, ifdown, dev->net,
835 "stop fail (%d) usbnet usb-%s-%s, %s\n",
836 retval,
837 dev->udev->bus->bus_name, dev->udev->devpath,
838 info->description);
839 }
840
841 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
842 usbnet_terminate_urbs(dev);
843
844 usbnet_status_stop(dev);
845
846 usbnet_purge_paused_rxq(dev);
847
848 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
849
850 /* deferred work (timer, softirq, task) must also stop */
851 dev->flags = 0;
852 del_timer_sync(&dev->delay);
853 tasklet_kill(&dev->bh);
854 cancel_work_sync(&dev->kevent);
855
856 /* We have cyclic dependencies. Those calls are needed
857 * to break a cycle. We cannot fall into the gaps because
858 * we have a flag
859 */
860 tasklet_kill(&dev->bh);
861 del_timer_sync(&dev->delay);
862 cancel_work_sync(&dev->kevent);
863
864 if (!pm)
865 usb_autopm_put_interface(dev->intf);
866
867 if (info->manage_power && mpn)
868 info->manage_power(dev, 0);
869 else
870 usb_autopm_put_interface(dev->intf);
871
872 return 0;
873 }
874 EXPORT_SYMBOL_GPL(usbnet_stop);
875
876 /*-------------------------------------------------------------------------*/
877
878 // posts reads, and enables write queuing
879
880 // precondition: never called in_interrupt
881
usbnet_open(struct net_device * net)882 int usbnet_open (struct net_device *net)
883 {
884 struct usbnet *dev = netdev_priv(net);
885 int retval;
886 const struct driver_info *info = dev->driver_info;
887
888 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
889 netif_info(dev, ifup, dev->net,
890 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
891 retval,
892 dev->udev->bus->bus_name,
893 dev->udev->devpath,
894 info->description);
895 goto done_nopm;
896 }
897
898 // put into "known safe" state
899 if (info->reset && (retval = info->reset (dev)) < 0) {
900 netif_info(dev, ifup, dev->net,
901 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
902 retval,
903 dev->udev->bus->bus_name,
904 dev->udev->devpath,
905 info->description);
906 goto done;
907 }
908
909 /* hard_mtu or rx_urb_size may change in reset() */
910 usbnet_update_max_qlen(dev);
911
912 // insist peer be connected
913 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
914 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
915 goto done;
916 }
917
918 /* start any status interrupt transfer */
919 if (dev->interrupt) {
920 retval = usbnet_status_start(dev, GFP_KERNEL);
921 if (retval < 0) {
922 netif_err(dev, ifup, dev->net,
923 "intr submit %d\n", retval);
924 goto done;
925 }
926 }
927
928 set_bit(EVENT_DEV_OPEN, &dev->flags);
929 netif_start_queue (net);
930 netif_info(dev, ifup, dev->net,
931 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
932 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
933 dev->net->mtu,
934 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
935 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
936 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
937 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
938 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
939 "simple");
940
941 /* reset rx error state */
942 dev->pkt_cnt = 0;
943 dev->pkt_err = 0;
944 clear_bit(EVENT_RX_KILL, &dev->flags);
945
946 // delay posting reads until we're fully open
947 tasklet_schedule (&dev->bh);
948 if (info->manage_power) {
949 retval = info->manage_power(dev, 1);
950 if (retval < 0) {
951 retval = 0;
952 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
953 } else {
954 usb_autopm_put_interface(dev->intf);
955 }
956 }
957 return retval;
958 done:
959 usb_autopm_put_interface(dev->intf);
960 done_nopm:
961 return retval;
962 }
963 EXPORT_SYMBOL_GPL(usbnet_open);
964
965 /*-------------------------------------------------------------------------*/
966
967 /* ethtool methods; minidrivers may need to add some more, but
968 * they'll probably want to use this base set.
969 */
970
971 /* These methods are written on the assumption that the device
972 * uses MII
973 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)974 int usbnet_get_link_ksettings_mii(struct net_device *net,
975 struct ethtool_link_ksettings *cmd)
976 {
977 struct usbnet *dev = netdev_priv(net);
978
979 if (!dev->mii.mdio_read)
980 return -EOPNOTSUPP;
981
982 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
983
984 return 0;
985 }
986 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
987
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)988 int usbnet_get_link_ksettings_internal(struct net_device *net,
989 struct ethtool_link_ksettings *cmd)
990 {
991 struct usbnet *dev = netdev_priv(net);
992
993 /* the assumption that speed is equal on tx and rx
994 * is deeply engrained into the networking layer.
995 * For wireless stuff it is not true.
996 * We assume that rx_speed matters more.
997 */
998 if (dev->rx_speed != SPEED_UNSET)
999 cmd->base.speed = dev->rx_speed / 1000000;
1000 else if (dev->tx_speed != SPEED_UNSET)
1001 cmd->base.speed = dev->tx_speed / 1000000;
1002 else
1003 cmd->base.speed = SPEED_UNKNOWN;
1004
1005 return 0;
1006 }
1007 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1008
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1009 int usbnet_set_link_ksettings_mii(struct net_device *net,
1010 const struct ethtool_link_ksettings *cmd)
1011 {
1012 struct usbnet *dev = netdev_priv(net);
1013 int retval;
1014
1015 if (!dev->mii.mdio_write)
1016 return -EOPNOTSUPP;
1017
1018 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1019
1020 /* link speed/duplex might have changed */
1021 if (dev->driver_info->link_reset)
1022 dev->driver_info->link_reset(dev);
1023
1024 /* hard_mtu or rx_urb_size may change in link_reset() */
1025 usbnet_update_max_qlen(dev);
1026
1027 return retval;
1028 }
1029 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1030
usbnet_get_link(struct net_device * net)1031 u32 usbnet_get_link (struct net_device *net)
1032 {
1033 struct usbnet *dev = netdev_priv(net);
1034
1035 /* If a check_connect is defined, return its result */
1036 if (dev->driver_info->check_connect)
1037 return dev->driver_info->check_connect (dev) == 0;
1038
1039 /* if the device has mii operations, use those */
1040 if (dev->mii.mdio_read)
1041 return mii_link_ok(&dev->mii);
1042
1043 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1044 return ethtool_op_get_link(net);
1045 }
1046 EXPORT_SYMBOL_GPL(usbnet_get_link);
1047
usbnet_nway_reset(struct net_device * net)1048 int usbnet_nway_reset(struct net_device *net)
1049 {
1050 struct usbnet *dev = netdev_priv(net);
1051
1052 if (!dev->mii.mdio_write)
1053 return -EOPNOTSUPP;
1054
1055 return mii_nway_restart(&dev->mii);
1056 }
1057 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1058
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1059 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1060 {
1061 struct usbnet *dev = netdev_priv(net);
1062
1063 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1064 strscpy(info->fw_version, dev->driver_info->description,
1065 sizeof(info->fw_version));
1066 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1067 }
1068 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1069
usbnet_get_msglevel(struct net_device * net)1070 u32 usbnet_get_msglevel (struct net_device *net)
1071 {
1072 struct usbnet *dev = netdev_priv(net);
1073
1074 return dev->msg_enable;
1075 }
1076 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1077
usbnet_set_msglevel(struct net_device * net,u32 level)1078 void usbnet_set_msglevel (struct net_device *net, u32 level)
1079 {
1080 struct usbnet *dev = netdev_priv(net);
1081
1082 dev->msg_enable = level;
1083 }
1084 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1085
1086 /* drivers may override default ethtool_ops in their bind() routine */
1087 static const struct ethtool_ops usbnet_ethtool_ops = {
1088 .get_link = usbnet_get_link,
1089 .nway_reset = usbnet_nway_reset,
1090 .get_drvinfo = usbnet_get_drvinfo,
1091 .get_msglevel = usbnet_get_msglevel,
1092 .set_msglevel = usbnet_set_msglevel,
1093 .get_ts_info = ethtool_op_get_ts_info,
1094 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1095 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1096 };
1097
1098 /*-------------------------------------------------------------------------*/
1099
__handle_link_change(struct usbnet * dev)1100 static void __handle_link_change(struct usbnet *dev)
1101 {
1102 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1103 return;
1104
1105 if (!netif_carrier_ok(dev->net)) {
1106 /* kill URBs for reading packets to save bus bandwidth */
1107 unlink_urbs(dev, &dev->rxq);
1108
1109 /*
1110 * tx_timeout will unlink URBs for sending packets and
1111 * tx queue is stopped by netcore after link becomes off
1112 */
1113 } else {
1114 /* submitting URBs for reading packets */
1115 tasklet_schedule(&dev->bh);
1116 }
1117
1118 /* hard_mtu or rx_urb_size may change during link change */
1119 usbnet_update_max_qlen(dev);
1120
1121 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1122 }
1123
usbnet_set_rx_mode(struct net_device * net)1124 void usbnet_set_rx_mode(struct net_device *net)
1125 {
1126 struct usbnet *dev = netdev_priv(net);
1127
1128 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1129 }
1130 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1131
__handle_set_rx_mode(struct usbnet * dev)1132 static void __handle_set_rx_mode(struct usbnet *dev)
1133 {
1134 if (dev->driver_info->set_rx_mode)
1135 (dev->driver_info->set_rx_mode)(dev);
1136
1137 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1138 }
1139
1140 /* work that cannot be done in interrupt context uses keventd.
1141 *
1142 * NOTE: with 2.5 we could do more of this using completion callbacks,
1143 * especially now that control transfers can be queued.
1144 */
1145 static void
usbnet_deferred_kevent(struct work_struct * work)1146 usbnet_deferred_kevent (struct work_struct *work)
1147 {
1148 struct usbnet *dev =
1149 container_of(work, struct usbnet, kevent);
1150 int status;
1151
1152 /* usb_clear_halt() needs a thread context */
1153 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1154 unlink_urbs (dev, &dev->txq);
1155 status = usb_autopm_get_interface(dev->intf);
1156 if (status < 0)
1157 goto fail_pipe;
1158 status = usb_clear_halt (dev->udev, dev->out);
1159 usb_autopm_put_interface(dev->intf);
1160 if (status < 0 &&
1161 status != -EPIPE &&
1162 status != -ESHUTDOWN) {
1163 if (netif_msg_tx_err (dev))
1164 fail_pipe:
1165 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1166 status);
1167 } else {
1168 clear_bit (EVENT_TX_HALT, &dev->flags);
1169 if (status != -ESHUTDOWN)
1170 netif_wake_queue (dev->net);
1171 }
1172 }
1173 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1174 unlink_urbs (dev, &dev->rxq);
1175 status = usb_autopm_get_interface(dev->intf);
1176 if (status < 0)
1177 goto fail_halt;
1178 status = usb_clear_halt (dev->udev, dev->in);
1179 usb_autopm_put_interface(dev->intf);
1180 if (status < 0 &&
1181 status != -EPIPE &&
1182 status != -ESHUTDOWN) {
1183 if (netif_msg_rx_err (dev))
1184 fail_halt:
1185 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1186 status);
1187 } else {
1188 clear_bit (EVENT_RX_HALT, &dev->flags);
1189 if (!usbnet_going_away(dev))
1190 tasklet_schedule(&dev->bh);
1191 }
1192 }
1193
1194 /* tasklet could resubmit itself forever if memory is tight */
1195 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1196 struct urb *urb = NULL;
1197 int resched = 1;
1198
1199 if (netif_running (dev->net))
1200 urb = usb_alloc_urb (0, GFP_KERNEL);
1201 else
1202 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1203 if (urb != NULL) {
1204 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1205 status = usb_autopm_get_interface(dev->intf);
1206 if (status < 0) {
1207 usb_free_urb(urb);
1208 goto fail_lowmem;
1209 }
1210 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1211 resched = 0;
1212 usb_autopm_put_interface(dev->intf);
1213 fail_lowmem:
1214 if (resched)
1215 if (!usbnet_going_away(dev))
1216 tasklet_schedule(&dev->bh);
1217 }
1218 }
1219
1220 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1221 const struct driver_info *info = dev->driver_info;
1222 int retval = 0;
1223
1224 clear_bit (EVENT_LINK_RESET, &dev->flags);
1225 status = usb_autopm_get_interface(dev->intf);
1226 if (status < 0)
1227 goto skip_reset;
1228 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1229 usb_autopm_put_interface(dev->intf);
1230 skip_reset:
1231 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1232 retval,
1233 dev->udev->bus->bus_name,
1234 dev->udev->devpath,
1235 info->description);
1236 } else {
1237 usb_autopm_put_interface(dev->intf);
1238 }
1239
1240 /* handle link change from link resetting */
1241 __handle_link_change(dev);
1242 }
1243
1244 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1245 __handle_link_change(dev);
1246
1247 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1248 __handle_set_rx_mode(dev);
1249
1250
1251 if (dev->flags)
1252 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1253 }
1254
1255 /*-------------------------------------------------------------------------*/
1256
tx_complete(struct urb * urb)1257 static void tx_complete (struct urb *urb)
1258 {
1259 struct sk_buff *skb = (struct sk_buff *) urb->context;
1260 struct skb_data *entry = (struct skb_data *) skb->cb;
1261 struct usbnet *dev = entry->dev;
1262
1263 if (urb->status == 0) {
1264 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1265 unsigned long flags;
1266
1267 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1268 u64_stats_add(&stats64->tx_packets, entry->packets);
1269 u64_stats_add(&stats64->tx_bytes, entry->length);
1270 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1271 } else {
1272 dev->net->stats.tx_errors++;
1273
1274 switch (urb->status) {
1275 case -EPIPE:
1276 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1277 break;
1278
1279 /* software-driven interface shutdown */
1280 case -ECONNRESET: // async unlink
1281 case -ESHUTDOWN: // hardware gone
1282 break;
1283
1284 /* like rx, tx gets controller i/o faults during hub_wq
1285 * delays and so it uses the same throttling mechanism.
1286 */
1287 case -EPROTO:
1288 case -ETIME:
1289 case -EILSEQ:
1290 usb_mark_last_busy(dev->udev);
1291 if (!timer_pending (&dev->delay)) {
1292 mod_timer (&dev->delay,
1293 jiffies + THROTTLE_JIFFIES);
1294 netif_dbg(dev, link, dev->net,
1295 "tx throttle %d\n", urb->status);
1296 }
1297 netif_stop_queue (dev->net);
1298 break;
1299 default:
1300 netif_dbg(dev, tx_err, dev->net,
1301 "tx err %d\n", entry->urb->status);
1302 break;
1303 }
1304 }
1305
1306 usb_autopm_put_interface_async(dev->intf);
1307 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1308 }
1309
1310 /*-------------------------------------------------------------------------*/
1311
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1312 void usbnet_tx_timeout (struct net_device *net, unsigned int txqueue)
1313 {
1314 struct usbnet *dev = netdev_priv(net);
1315
1316 unlink_urbs (dev, &dev->txq);
1317 tasklet_schedule (&dev->bh);
1318 /* this needs to be handled individually because the generic layer
1319 * doesn't know what is sufficient and could not restore private
1320 * information if a remedy of an unconditional reset were used.
1321 */
1322 if (dev->driver_info->recover)
1323 (dev->driver_info->recover)(dev);
1324 }
1325 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1326
1327 /*-------------------------------------------------------------------------*/
1328
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1329 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1330 {
1331 unsigned num_sgs, total_len = 0;
1332 int i, s = 0;
1333
1334 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1335 if (num_sgs == 1)
1336 return 0;
1337
1338 /* reserve one for zero packet */
1339 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1340 GFP_ATOMIC);
1341 if (!urb->sg)
1342 return -ENOMEM;
1343
1344 urb->num_sgs = num_sgs;
1345 sg_init_table(urb->sg, urb->num_sgs + 1);
1346
1347 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1348 total_len += skb_headlen(skb);
1349
1350 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1351 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1352
1353 total_len += skb_frag_size(f);
1354 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1355 skb_frag_off(f));
1356 }
1357 urb->transfer_buffer_length = total_len;
1358
1359 return 1;
1360 }
1361
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1362 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1363 struct net_device *net)
1364 {
1365 struct usbnet *dev = netdev_priv(net);
1366 unsigned int length;
1367 struct urb *urb = NULL;
1368 struct skb_data *entry;
1369 const struct driver_info *info = dev->driver_info;
1370 unsigned long flags;
1371 int retval;
1372
1373 if (skb)
1374 skb_tx_timestamp(skb);
1375
1376 // some devices want funky USB-level framing, for
1377 // win32 driver (usually) and/or hardware quirks
1378 if (info->tx_fixup) {
1379 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1380 if (!skb) {
1381 /* packet collected; minidriver waiting for more */
1382 if (info->flags & FLAG_MULTI_PACKET)
1383 goto not_drop;
1384 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1385 goto drop;
1386 }
1387 }
1388
1389 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1390 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1391 goto drop;
1392 }
1393
1394 entry = (struct skb_data *) skb->cb;
1395 entry->urb = urb;
1396 entry->dev = dev;
1397
1398 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1399 skb->data, skb->len, tx_complete, skb);
1400 if (dev->can_dma_sg) {
1401 if (build_dma_sg(skb, urb) < 0)
1402 goto drop;
1403 }
1404 length = urb->transfer_buffer_length;
1405
1406 /* don't assume the hardware handles USB_ZERO_PACKET
1407 * NOTE: strictly conforming cdc-ether devices should expect
1408 * the ZLP here, but ignore the one-byte packet.
1409 * NOTE2: CDC NCM specification is different from CDC ECM when
1410 * handling ZLP/short packets, so cdc_ncm driver will make short
1411 * packet itself if needed.
1412 */
1413 if (length % dev->maxpacket == 0) {
1414 if (!(info->flags & FLAG_SEND_ZLP)) {
1415 if (!(info->flags & FLAG_MULTI_PACKET)) {
1416 length++;
1417 if (skb_tailroom(skb) && !urb->num_sgs) {
1418 skb->data[skb->len] = 0;
1419 __skb_put(skb, 1);
1420 } else if (urb->num_sgs)
1421 sg_set_buf(&urb->sg[urb->num_sgs++],
1422 dev->padding_pkt, 1);
1423 }
1424 } else
1425 urb->transfer_flags |= URB_ZERO_PACKET;
1426 }
1427 urb->transfer_buffer_length = length;
1428
1429 if (info->flags & FLAG_MULTI_PACKET) {
1430 /* Driver has set number of packets and a length delta.
1431 * Calculate the complete length and ensure that it's
1432 * positive.
1433 */
1434 entry->length += length;
1435 if (WARN_ON_ONCE(entry->length <= 0))
1436 entry->length = length;
1437 } else {
1438 usbnet_set_skb_tx_stats(skb, 1, length);
1439 }
1440
1441 spin_lock_irqsave(&dev->txq.lock, flags);
1442 retval = usb_autopm_get_interface_async(dev->intf);
1443 if (retval < 0) {
1444 spin_unlock_irqrestore(&dev->txq.lock, flags);
1445 goto drop;
1446 }
1447 if (netif_queue_stopped(net)) {
1448 usb_autopm_put_interface_async(dev->intf);
1449 spin_unlock_irqrestore(&dev->txq.lock, flags);
1450 goto drop;
1451 }
1452
1453 #ifdef CONFIG_PM
1454 /* if this triggers the device is still a sleep */
1455 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1456 /* transmission will be done in resume */
1457 usb_anchor_urb(urb, &dev->deferred);
1458 /* no use to process more packets */
1459 netif_stop_queue(net);
1460 usb_put_urb(urb);
1461 spin_unlock_irqrestore(&dev->txq.lock, flags);
1462 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1463 goto deferred;
1464 }
1465 #endif
1466
1467 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1468 case -EPIPE:
1469 netif_stop_queue (net);
1470 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1471 usb_autopm_put_interface_async(dev->intf);
1472 break;
1473 default:
1474 usb_autopm_put_interface_async(dev->intf);
1475 netif_dbg(dev, tx_err, dev->net,
1476 "tx: submit urb err %d\n", retval);
1477 break;
1478 case 0:
1479 netif_trans_update(net);
1480 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1481 if (dev->txq.qlen >= TX_QLEN (dev))
1482 netif_stop_queue (net);
1483 }
1484 spin_unlock_irqrestore (&dev->txq.lock, flags);
1485
1486 if (retval) {
1487 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1488 drop:
1489 dev->net->stats.tx_dropped++;
1490 not_drop:
1491 if (skb)
1492 dev_kfree_skb_any (skb);
1493 if (urb) {
1494 kfree(urb->sg);
1495 usb_free_urb(urb);
1496 }
1497 } else
1498 netif_dbg(dev, tx_queued, dev->net,
1499 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1500 #ifdef CONFIG_PM
1501 deferred:
1502 #endif
1503 return NETDEV_TX_OK;
1504 }
1505 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1506
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1507 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1508 {
1509 struct urb *urb;
1510 int i;
1511 int ret = 0;
1512
1513 /* don't refill the queue all at once */
1514 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1515 urb = usb_alloc_urb(0, flags);
1516 if (urb != NULL) {
1517 ret = rx_submit(dev, urb, flags);
1518 if (ret)
1519 goto err;
1520 } else {
1521 ret = -ENOMEM;
1522 goto err;
1523 }
1524 }
1525 err:
1526 return ret;
1527 }
1528
usb_free_skb(struct sk_buff * skb)1529 static inline void usb_free_skb(struct sk_buff *skb)
1530 {
1531 struct skb_data *entry = (struct skb_data *)skb->cb;
1532
1533 usb_free_urb(entry->urb);
1534 dev_kfree_skb(skb);
1535 }
1536
1537 /*-------------------------------------------------------------------------*/
1538
1539 // tasklet (work deferred from completions, in_irq) or timer
1540
usbnet_bh(struct timer_list * t)1541 static void usbnet_bh (struct timer_list *t)
1542 {
1543 struct usbnet *dev = from_timer(dev, t, delay);
1544 struct sk_buff *skb;
1545 struct skb_data *entry;
1546
1547 while ((skb = skb_dequeue (&dev->done))) {
1548 entry = (struct skb_data *) skb->cb;
1549 switch (entry->state) {
1550 case rx_done:
1551 if (rx_process(dev, skb))
1552 usb_free_skb(skb);
1553 continue;
1554 case tx_done:
1555 kfree(entry->urb->sg);
1556 fallthrough;
1557 case rx_cleanup:
1558 usb_free_skb(skb);
1559 continue;
1560 default:
1561 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1562 }
1563 }
1564
1565 /* restart RX again after disabling due to high error rate */
1566 clear_bit(EVENT_RX_KILL, &dev->flags);
1567
1568 /* waiting for all pending urbs to complete?
1569 * only then can we forgo submitting anew
1570 */
1571 if (waitqueue_active(&dev->wait)) {
1572 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1573 wake_up_all(&dev->wait);
1574
1575 // or are we maybe short a few urbs?
1576 } else if (netif_running (dev->net) &&
1577 netif_device_present (dev->net) &&
1578 netif_carrier_ok(dev->net) &&
1579 !usbnet_going_away(dev) &&
1580 !timer_pending(&dev->delay) &&
1581 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1582 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1583 int temp = dev->rxq.qlen;
1584
1585 if (temp < RX_QLEN(dev)) {
1586 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1587 return;
1588 if (temp != dev->rxq.qlen)
1589 netif_dbg(dev, link, dev->net,
1590 "rxqlen %d --> %d\n",
1591 temp, dev->rxq.qlen);
1592 if (dev->rxq.qlen < RX_QLEN(dev))
1593 tasklet_schedule (&dev->bh);
1594 }
1595 if (dev->txq.qlen < TX_QLEN (dev))
1596 netif_wake_queue (dev->net);
1597 }
1598 }
1599
usbnet_bh_tasklet(struct tasklet_struct * t)1600 static void usbnet_bh_tasklet(struct tasklet_struct *t)
1601 {
1602 struct usbnet *dev = from_tasklet(dev, t, bh);
1603
1604 usbnet_bh(&dev->delay);
1605 }
1606
1607
1608 /*-------------------------------------------------------------------------
1609 *
1610 * USB Device Driver support
1611 *
1612 *-------------------------------------------------------------------------*/
1613
1614 // precondition: never called in_interrupt
1615
usbnet_disconnect(struct usb_interface * intf)1616 void usbnet_disconnect (struct usb_interface *intf)
1617 {
1618 struct usbnet *dev;
1619 struct usb_device *xdev;
1620 struct net_device *net;
1621 struct urb *urb;
1622
1623 dev = usb_get_intfdata(intf);
1624 usb_set_intfdata(intf, NULL);
1625 if (!dev)
1626 return;
1627 usbnet_mark_going_away(dev);
1628
1629 xdev = interface_to_usbdev (intf);
1630
1631 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1632 intf->dev.driver->name,
1633 xdev->bus->bus_name, xdev->devpath,
1634 dev->driver_info->description);
1635
1636 net = dev->net;
1637 unregister_netdev (net);
1638
1639 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1640 dev_kfree_skb(urb->context);
1641 kfree(urb->sg);
1642 usb_free_urb(urb);
1643 }
1644
1645 if (dev->driver_info->unbind)
1646 dev->driver_info->unbind(dev, intf);
1647
1648 usb_kill_urb(dev->interrupt);
1649 usb_free_urb(dev->interrupt);
1650 kfree(dev->padding_pkt);
1651
1652 free_percpu(net->tstats);
1653 free_netdev(net);
1654 }
1655 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1656
1657 static const struct net_device_ops usbnet_netdev_ops = {
1658 .ndo_open = usbnet_open,
1659 .ndo_stop = usbnet_stop,
1660 .ndo_start_xmit = usbnet_start_xmit,
1661 .ndo_tx_timeout = usbnet_tx_timeout,
1662 .ndo_set_rx_mode = usbnet_set_rx_mode,
1663 .ndo_change_mtu = usbnet_change_mtu,
1664 .ndo_get_stats64 = dev_get_tstats64,
1665 .ndo_set_mac_address = eth_mac_addr,
1666 .ndo_validate_addr = eth_validate_addr,
1667 };
1668
1669 /*-------------------------------------------------------------------------*/
1670
1671 // precondition: never called in_interrupt
1672
1673 static struct device_type wlan_type = {
1674 .name = "wlan",
1675 };
1676
1677 static struct device_type wwan_type = {
1678 .name = "wwan",
1679 };
1680
1681 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1682 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1683 {
1684 struct usbnet *dev;
1685 struct net_device *net;
1686 struct usb_host_interface *interface;
1687 const struct driver_info *info;
1688 struct usb_device *xdev;
1689 int status;
1690 const char *name;
1691 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1692
1693 /* usbnet already took usb runtime pm, so have to enable the feature
1694 * for usb interface, otherwise usb_autopm_get_interface may return
1695 * failure if RUNTIME_PM is enabled.
1696 */
1697 if (!driver->supports_autosuspend) {
1698 driver->supports_autosuspend = 1;
1699 pm_runtime_enable(&udev->dev);
1700 }
1701
1702 name = udev->dev.driver->name;
1703 info = (const struct driver_info *) prod->driver_info;
1704 if (!info) {
1705 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1706 return -ENODEV;
1707 }
1708 xdev = interface_to_usbdev (udev);
1709 interface = udev->cur_altsetting;
1710
1711 status = -ENOMEM;
1712
1713 // set up our own records
1714 net = alloc_etherdev(sizeof(*dev));
1715 if (!net)
1716 goto out;
1717
1718 /* netdev_printk() needs this so do it as early as possible */
1719 SET_NETDEV_DEV(net, &udev->dev);
1720
1721 dev = netdev_priv(net);
1722 dev->udev = xdev;
1723 dev->intf = udev;
1724 dev->driver_info = info;
1725 dev->driver_name = name;
1726 dev->rx_speed = SPEED_UNSET;
1727 dev->tx_speed = SPEED_UNSET;
1728
1729 net->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1730 if (!net->tstats)
1731 goto out0;
1732
1733 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1734 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1735 init_waitqueue_head(&dev->wait);
1736 skb_queue_head_init (&dev->rxq);
1737 skb_queue_head_init (&dev->txq);
1738 skb_queue_head_init (&dev->done);
1739 skb_queue_head_init(&dev->rxq_pause);
1740 tasklet_setup(&dev->bh, usbnet_bh_tasklet);
1741 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1742 init_usb_anchor(&dev->deferred);
1743 timer_setup(&dev->delay, usbnet_bh, 0);
1744 mutex_init (&dev->phy_mutex);
1745 mutex_init(&dev->interrupt_mutex);
1746 dev->interrupt_count = 0;
1747
1748 dev->net = net;
1749 strscpy(net->name, "usb%d", sizeof(net->name));
1750
1751 /* rx and tx sides can use different message sizes;
1752 * bind() should set rx_urb_size in that case.
1753 */
1754 dev->hard_mtu = net->mtu + net->hard_header_len;
1755 net->min_mtu = 0;
1756 net->max_mtu = ETH_MAX_MTU;
1757
1758 net->netdev_ops = &usbnet_netdev_ops;
1759 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1760 net->ethtool_ops = &usbnet_ethtool_ops;
1761
1762 // allow device-specific bind/init procedures
1763 // NOTE net->name still not usable ...
1764 if (info->bind) {
1765 status = info->bind (dev, udev);
1766 if (status < 0)
1767 goto out1;
1768
1769 // heuristic: "usb%d" for links we know are two-host,
1770 // else "eth%d" when there's reasonable doubt. userspace
1771 // can rename the link if it knows better.
1772 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1773 ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1774 (net->dev_addr [0] & 0x02) == 0))
1775 strscpy(net->name, "eth%d", sizeof(net->name));
1776 /* WLAN devices should always be named "wlan%d" */
1777 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1778 strscpy(net->name, "wlan%d", sizeof(net->name));
1779 /* WWAN devices should always be named "wwan%d" */
1780 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1781 strscpy(net->name, "wwan%d", sizeof(net->name));
1782
1783 /* devices that cannot do ARP */
1784 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1785 net->flags |= IFF_NOARP;
1786
1787 /* maybe the remote can't receive an Ethernet MTU */
1788 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1789 net->mtu = dev->hard_mtu - net->hard_header_len;
1790 } else if (!info->in || !info->out)
1791 status = usbnet_get_endpoints (dev, udev);
1792 else {
1793 u8 ep_addrs[3] = {
1794 info->in + USB_DIR_IN, info->out + USB_DIR_OUT, 0
1795 };
1796
1797 dev->in = usb_rcvbulkpipe (xdev, info->in);
1798 dev->out = usb_sndbulkpipe (xdev, info->out);
1799 if (!(info->flags & FLAG_NO_SETINT))
1800 status = usb_set_interface (xdev,
1801 interface->desc.bInterfaceNumber,
1802 interface->desc.bAlternateSetting);
1803 else
1804 status = 0;
1805
1806 if (status == 0 && !usb_check_bulk_endpoints(udev, ep_addrs))
1807 status = -EINVAL;
1808 }
1809 if (status >= 0 && dev->status)
1810 status = init_status (dev, udev);
1811 if (status < 0)
1812 goto out3;
1813
1814 if (!dev->rx_urb_size)
1815 dev->rx_urb_size = dev->hard_mtu;
1816 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1817 if (dev->maxpacket == 0) {
1818 /* that is a broken device */
1819 status = -ENODEV;
1820 goto out4;
1821 }
1822
1823 /* this flags the device for user space */
1824 if (!is_valid_ether_addr(net->dev_addr))
1825 eth_hw_addr_random(net);
1826
1827 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1828 SET_NETDEV_DEVTYPE(net, &wlan_type);
1829 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1830 SET_NETDEV_DEVTYPE(net, &wwan_type);
1831
1832 /* initialize max rx_qlen and tx_qlen */
1833 usbnet_update_max_qlen(dev);
1834
1835 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1836 !(info->flags & FLAG_MULTI_PACKET)) {
1837 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1838 if (!dev->padding_pkt) {
1839 status = -ENOMEM;
1840 goto out4;
1841 }
1842 }
1843
1844 status = register_netdev (net);
1845 if (status)
1846 goto out5;
1847 netif_info(dev, probe, dev->net,
1848 "register '%s' at usb-%s-%s, %s, %pM\n",
1849 udev->dev.driver->name,
1850 xdev->bus->bus_name, xdev->devpath,
1851 dev->driver_info->description,
1852 net->dev_addr);
1853
1854 // ok, it's ready to go.
1855 usb_set_intfdata (udev, dev);
1856
1857 netif_device_attach (net);
1858
1859 if (dev->driver_info->flags & FLAG_LINK_INTR)
1860 usbnet_link_change(dev, 0, 0);
1861
1862 return 0;
1863
1864 out5:
1865 kfree(dev->padding_pkt);
1866 out4:
1867 usb_free_urb(dev->interrupt);
1868 out3:
1869 if (info->unbind)
1870 info->unbind (dev, udev);
1871 out1:
1872 /* subdrivers must undo all they did in bind() if they
1873 * fail it, but we may fail later and a deferred kevent
1874 * may trigger an error resubmitting itself and, worse,
1875 * schedule a timer. So we kill it all just in case.
1876 */
1877 cancel_work_sync(&dev->kevent);
1878 del_timer_sync(&dev->delay);
1879 free_percpu(net->tstats);
1880 out0:
1881 free_netdev(net);
1882 out:
1883 return status;
1884 }
1885 EXPORT_SYMBOL_GPL(usbnet_probe);
1886
1887 /*-------------------------------------------------------------------------*/
1888
1889 /*
1890 * suspend the whole driver as soon as the first interface is suspended
1891 * resume only when the last interface is resumed
1892 */
1893
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1894 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1895 {
1896 struct usbnet *dev = usb_get_intfdata(intf);
1897
1898 if (!dev->suspend_count++) {
1899 spin_lock_irq(&dev->txq.lock);
1900 /* don't autosuspend while transmitting */
1901 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1902 dev->suspend_count--;
1903 spin_unlock_irq(&dev->txq.lock);
1904 return -EBUSY;
1905 } else {
1906 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1907 spin_unlock_irq(&dev->txq.lock);
1908 }
1909 /*
1910 * accelerate emptying of the rx and queues, to avoid
1911 * having everything error out.
1912 */
1913 netif_device_detach (dev->net);
1914 usbnet_terminate_urbs(dev);
1915 __usbnet_status_stop_force(dev);
1916
1917 /*
1918 * reattach so runtime management can use and
1919 * wake the device
1920 */
1921 netif_device_attach (dev->net);
1922 }
1923 return 0;
1924 }
1925 EXPORT_SYMBOL_GPL(usbnet_suspend);
1926
usbnet_resume(struct usb_interface * intf)1927 int usbnet_resume (struct usb_interface *intf)
1928 {
1929 struct usbnet *dev = usb_get_intfdata(intf);
1930 struct sk_buff *skb;
1931 struct urb *res;
1932 int retval;
1933
1934 if (!--dev->suspend_count) {
1935 /* resume interrupt URB if it was previously submitted */
1936 __usbnet_status_start_force(dev, GFP_NOIO);
1937
1938 spin_lock_irq(&dev->txq.lock);
1939 while ((res = usb_get_from_anchor(&dev->deferred))) {
1940
1941 skb = (struct sk_buff *)res->context;
1942 retval = usb_submit_urb(res, GFP_ATOMIC);
1943 if (retval < 0) {
1944 dev_kfree_skb_any(skb);
1945 kfree(res->sg);
1946 usb_free_urb(res);
1947 usb_autopm_put_interface_async(dev->intf);
1948 } else {
1949 netif_trans_update(dev->net);
1950 __skb_queue_tail(&dev->txq, skb);
1951 }
1952 }
1953
1954 smp_mb();
1955 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1956 spin_unlock_irq(&dev->txq.lock);
1957
1958 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1959 /* handle remote wakeup ASAP
1960 * we cannot race against stop
1961 */
1962 if (netif_device_present(dev->net) &&
1963 !timer_pending(&dev->delay) &&
1964 !test_bit(EVENT_RX_HALT, &dev->flags))
1965 rx_alloc_submit(dev, GFP_NOIO);
1966
1967 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1968 netif_tx_wake_all_queues(dev->net);
1969 tasklet_schedule (&dev->bh);
1970 }
1971 }
1972
1973 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1974 usb_autopm_get_interface_no_resume(intf);
1975
1976 return 0;
1977 }
1978 EXPORT_SYMBOL_GPL(usbnet_resume);
1979
1980 /*
1981 * Either a subdriver implements manage_power, then it is assumed to always
1982 * be ready to be suspended or it reports the readiness to be suspended
1983 * explicitly
1984 */
usbnet_device_suggests_idle(struct usbnet * dev)1985 void usbnet_device_suggests_idle(struct usbnet *dev)
1986 {
1987 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1988 dev->intf->needs_remote_wakeup = 1;
1989 usb_autopm_put_interface_async(dev->intf);
1990 }
1991 }
1992 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1993
1994 /*
1995 * For devices that can do without special commands
1996 */
usbnet_manage_power(struct usbnet * dev,int on)1997 int usbnet_manage_power(struct usbnet *dev, int on)
1998 {
1999 dev->intf->needs_remote_wakeup = on;
2000 return 0;
2001 }
2002 EXPORT_SYMBOL(usbnet_manage_power);
2003
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)2004 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
2005 {
2006 /* update link after link is reseted */
2007 if (link && !need_reset)
2008 netif_carrier_on(dev->net);
2009 else
2010 netif_carrier_off(dev->net);
2011
2012 if (need_reset && link)
2013 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
2014 else
2015 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
2016 }
2017 EXPORT_SYMBOL(usbnet_link_change);
2018
2019 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2020 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2021 u16 value, u16 index, void *data, u16 size)
2022 {
2023 void *buf = NULL;
2024 int err = -ENOMEM;
2025
2026 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2027 " value=0x%04x index=0x%04x size=%d\n",
2028 cmd, reqtype, value, index, size);
2029
2030 if (size) {
2031 buf = kmalloc(size, GFP_NOIO);
2032 if (!buf)
2033 goto out;
2034 }
2035
2036 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2037 cmd, reqtype, value, index, buf, size,
2038 USB_CTRL_GET_TIMEOUT);
2039 if (err > 0 && err <= size) {
2040 if (data)
2041 memcpy(data, buf, err);
2042 else
2043 netdev_dbg(dev->net,
2044 "Huh? Data requested but thrown away.\n");
2045 }
2046 kfree(buf);
2047 out:
2048 return err;
2049 }
2050
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2051 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2052 u16 value, u16 index, const void *data,
2053 u16 size)
2054 {
2055 void *buf = NULL;
2056 int err = -ENOMEM;
2057
2058 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2059 " value=0x%04x index=0x%04x size=%d\n",
2060 cmd, reqtype, value, index, size);
2061
2062 if (data) {
2063 buf = kmemdup(data, size, GFP_NOIO);
2064 if (!buf)
2065 goto out;
2066 } else {
2067 if (size) {
2068 WARN_ON_ONCE(1);
2069 err = -EINVAL;
2070 goto out;
2071 }
2072 }
2073
2074 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2075 cmd, reqtype, value, index, buf, size,
2076 USB_CTRL_SET_TIMEOUT);
2077 kfree(buf);
2078
2079 out:
2080 return err;
2081 }
2082
2083 /*
2084 * The function can't be called inside suspend/resume callback,
2085 * otherwise deadlock will be caused.
2086 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2087 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2088 u16 value, u16 index, void *data, u16 size)
2089 {
2090 int ret;
2091
2092 if (usb_autopm_get_interface(dev->intf) < 0)
2093 return -ENODEV;
2094 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2095 data, size);
2096 usb_autopm_put_interface(dev->intf);
2097 return ret;
2098 }
2099 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2100
2101 /*
2102 * The function can't be called inside suspend/resume callback,
2103 * otherwise deadlock will be caused.
2104 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2105 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2106 u16 value, u16 index, const void *data, u16 size)
2107 {
2108 int ret;
2109
2110 if (usb_autopm_get_interface(dev->intf) < 0)
2111 return -ENODEV;
2112 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2113 data, size);
2114 usb_autopm_put_interface(dev->intf);
2115 return ret;
2116 }
2117 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2118
2119 /*
2120 * The function can be called inside suspend/resume callback safely
2121 * and should only be called by suspend/resume callback generally.
2122 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2123 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2124 u16 value, u16 index, void *data, u16 size)
2125 {
2126 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2127 data, size);
2128 }
2129 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2130
2131 /*
2132 * The function can be called inside suspend/resume callback safely
2133 * and should only be called by suspend/resume callback generally.
2134 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2135 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2136 u16 value, u16 index, const void *data,
2137 u16 size)
2138 {
2139 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2140 data, size);
2141 }
2142 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2143
usbnet_async_cmd_cb(struct urb * urb)2144 static void usbnet_async_cmd_cb(struct urb *urb)
2145 {
2146 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2147 int status = urb->status;
2148
2149 if (status < 0)
2150 dev_dbg(&urb->dev->dev, "%s failed with %d",
2151 __func__, status);
2152
2153 kfree(req);
2154 usb_free_urb(urb);
2155 }
2156
2157 /*
2158 * The caller must make sure that device can't be put into suspend
2159 * state until the control URB completes.
2160 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2161 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2162 u16 value, u16 index, const void *data, u16 size)
2163 {
2164 struct usb_ctrlrequest *req;
2165 struct urb *urb;
2166 int err = -ENOMEM;
2167 void *buf = NULL;
2168
2169 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2170 " value=0x%04x index=0x%04x size=%d\n",
2171 cmd, reqtype, value, index, size);
2172
2173 urb = usb_alloc_urb(0, GFP_ATOMIC);
2174 if (!urb)
2175 goto fail;
2176
2177 if (data) {
2178 buf = kmemdup(data, size, GFP_ATOMIC);
2179 if (!buf) {
2180 netdev_err(dev->net, "Error allocating buffer"
2181 " in %s!\n", __func__);
2182 goto fail_free_urb;
2183 }
2184 }
2185
2186 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2187 if (!req)
2188 goto fail_free_buf;
2189
2190 req->bRequestType = reqtype;
2191 req->bRequest = cmd;
2192 req->wValue = cpu_to_le16(value);
2193 req->wIndex = cpu_to_le16(index);
2194 req->wLength = cpu_to_le16(size);
2195
2196 usb_fill_control_urb(urb, dev->udev,
2197 usb_sndctrlpipe(dev->udev, 0),
2198 (void *)req, buf, size,
2199 usbnet_async_cmd_cb, req);
2200 urb->transfer_flags |= URB_FREE_BUFFER;
2201
2202 err = usb_submit_urb(urb, GFP_ATOMIC);
2203 if (err < 0) {
2204 netdev_err(dev->net, "Error submitting the control"
2205 " message: status=%d\n", err);
2206 goto fail_free_all;
2207 }
2208 return 0;
2209
2210 fail_free_all:
2211 kfree(req);
2212 fail_free_buf:
2213 kfree(buf);
2214 /*
2215 * avoid a double free
2216 * needed because the flag can be set only
2217 * after filling the URB
2218 */
2219 urb->transfer_flags = 0;
2220 fail_free_urb:
2221 usb_free_urb(urb);
2222 fail:
2223 return err;
2224
2225 }
2226 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2227 /*-------------------------------------------------------------------------*/
2228
usbnet_init(void)2229 static int __init usbnet_init(void)
2230 {
2231 /* Compiler should optimize this out. */
2232 BUILD_BUG_ON(
2233 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2234
2235 return 0;
2236 }
2237 module_init(usbnet_init);
2238
usbnet_exit(void)2239 static void __exit usbnet_exit(void)
2240 {
2241 }
2242 module_exit(usbnet_exit);
2243
2244 MODULE_AUTHOR("David Brownell");
2245 MODULE_DESCRIPTION("USB network driver framework");
2246 MODULE_LICENSE("GPL");
2247