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