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 (!schedule_work (&dev->kevent))
468 netdev_dbg(dev->net, "kevent %s may have been dropped\n", usbnet_event_names[work]);
469 else
470 netdev_dbg(dev->net, "kevent %s scheduled\n", usbnet_event_names[work]);
471 }
472 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
473
474 /*-------------------------------------------------------------------------*/
475
476 static void rx_complete (struct urb *urb);
477
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)478 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
479 {
480 struct sk_buff *skb;
481 struct skb_data *entry;
482 int retval = 0;
483 unsigned long lockflags;
484 size_t size = dev->rx_urb_size;
485
486 /* prevent rx skb allocation when error ratio is high */
487 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
488 usb_free_urb(urb);
489 return -ENOLINK;
490 }
491
492 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
493 skb = __netdev_alloc_skb(dev->net, size, flags);
494 else
495 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
496 if (!skb) {
497 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
498 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
499 usb_free_urb (urb);
500 return -ENOMEM;
501 }
502
503 entry = (struct skb_data *) skb->cb;
504 entry->urb = urb;
505 entry->dev = dev;
506 entry->length = 0;
507
508 usb_fill_bulk_urb (urb, dev->udev, dev->in,
509 skb->data, size, rx_complete, skb);
510
511 spin_lock_irqsave (&dev->rxq.lock, lockflags);
512
513 if (netif_running (dev->net) &&
514 netif_device_present (dev->net) &&
515 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
516 !test_bit (EVENT_RX_HALT, &dev->flags) &&
517 !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
518 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
519 case -EPIPE:
520 usbnet_defer_kevent (dev, EVENT_RX_HALT);
521 break;
522 case -ENOMEM:
523 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
524 break;
525 case -ENODEV:
526 netif_dbg(dev, ifdown, dev->net, "device gone\n");
527 netif_device_detach (dev->net);
528 break;
529 case -EHOSTUNREACH:
530 retval = -ENOLINK;
531 break;
532 default:
533 netif_dbg(dev, rx_err, dev->net,
534 "rx submit, %d\n", retval);
535 tasklet_schedule (&dev->bh);
536 break;
537 case 0:
538 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
539 }
540 } else {
541 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
542 retval = -ENOLINK;
543 }
544 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
545 if (retval) {
546 dev_kfree_skb_any (skb);
547 usb_free_urb (urb);
548 }
549 return retval;
550 }
551
552
553 /*-------------------------------------------------------------------------*/
554
rx_process(struct usbnet * dev,struct sk_buff * skb)555 static inline int rx_process(struct usbnet *dev, struct sk_buff *skb)
556 {
557 if (dev->driver_info->rx_fixup &&
558 !dev->driver_info->rx_fixup (dev, skb)) {
559 /* With RX_ASSEMBLE, rx_fixup() must update counters */
560 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
561 dev->net->stats.rx_errors++;
562 return -EPROTO;
563 }
564 // else network stack removes extra byte if we forced a short packet
565
566 /* all data was already cloned from skb inside the driver */
567 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
568 return -EALREADY;
569
570 if (skb->len < ETH_HLEN) {
571 dev->net->stats.rx_errors++;
572 dev->net->stats.rx_length_errors++;
573 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
574 return -EPROTO;
575 }
576
577 usbnet_skb_return(dev, skb);
578 return 0;
579 }
580
581 /*-------------------------------------------------------------------------*/
582
rx_complete(struct urb * urb)583 static void rx_complete (struct urb *urb)
584 {
585 struct sk_buff *skb = (struct sk_buff *) urb->context;
586 struct skb_data *entry = (struct skb_data *) skb->cb;
587 struct usbnet *dev = entry->dev;
588 int urb_status = urb->status;
589 enum skb_state state;
590
591 skb_put (skb, urb->actual_length);
592 state = rx_done;
593 entry->urb = NULL;
594
595 switch (urb_status) {
596 /* success */
597 case 0:
598 break;
599
600 /* stalls need manual reset. this is rare ... except that
601 * when going through USB 2.0 TTs, unplug appears this way.
602 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
603 * storm, recovering as needed.
604 */
605 case -EPIPE:
606 dev->net->stats.rx_errors++;
607 usbnet_defer_kevent (dev, EVENT_RX_HALT);
608 fallthrough;
609
610 /* software-driven interface shutdown */
611 case -ECONNRESET: /* async unlink */
612 case -ESHUTDOWN: /* hardware gone */
613 netif_dbg(dev, ifdown, dev->net,
614 "rx shutdown, code %d\n", urb_status);
615 goto block;
616
617 /* we get controller i/o faults during hub_wq disconnect() delays.
618 * throttle down resubmits, to avoid log floods; just temporarily,
619 * so we still recover when the fault isn't a hub_wq delay.
620 */
621 case -EPROTO:
622 case -ETIME:
623 case -EILSEQ:
624 dev->net->stats.rx_errors++;
625 if (!timer_pending (&dev->delay)) {
626 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
627 netif_dbg(dev, link, dev->net,
628 "rx throttle %d\n", urb_status);
629 }
630 block:
631 state = rx_cleanup;
632 entry->urb = urb;
633 urb = NULL;
634 break;
635
636 /* data overrun ... flush fifo? */
637 case -EOVERFLOW:
638 dev->net->stats.rx_over_errors++;
639 fallthrough;
640
641 default:
642 state = rx_cleanup;
643 dev->net->stats.rx_errors++;
644 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
645 break;
646 }
647
648 /* stop rx if packet error rate is high */
649 if (++dev->pkt_cnt > 30) {
650 dev->pkt_cnt = 0;
651 dev->pkt_err = 0;
652 } else {
653 if (state == rx_cleanup)
654 dev->pkt_err++;
655 if (dev->pkt_err > 20)
656 set_bit(EVENT_RX_KILL, &dev->flags);
657 }
658
659 state = defer_bh(dev, skb, &dev->rxq, state);
660
661 if (urb) {
662 if (netif_running (dev->net) &&
663 !test_bit (EVENT_RX_HALT, &dev->flags) &&
664 state != unlink_start) {
665 rx_submit (dev, urb, GFP_ATOMIC);
666 usb_mark_last_busy(dev->udev);
667 return;
668 }
669 usb_free_urb (urb);
670 }
671 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
672 }
673
674 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)675 void usbnet_pause_rx(struct usbnet *dev)
676 {
677 set_bit(EVENT_RX_PAUSED, &dev->flags);
678
679 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
680 }
681 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
682
usbnet_resume_rx(struct usbnet * dev)683 void usbnet_resume_rx(struct usbnet *dev)
684 {
685 struct sk_buff *skb;
686 int num = 0;
687
688 clear_bit(EVENT_RX_PAUSED, &dev->flags);
689
690 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
691 usbnet_skb_return(dev, skb);
692 num++;
693 }
694
695 tasklet_schedule(&dev->bh);
696
697 netif_dbg(dev, rx_status, dev->net,
698 "paused rx queue disabled, %d skbs requeued\n", num);
699 }
700 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
701
usbnet_purge_paused_rxq(struct usbnet * dev)702 void usbnet_purge_paused_rxq(struct usbnet *dev)
703 {
704 skb_queue_purge(&dev->rxq_pause);
705 }
706 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
707
708 /*-------------------------------------------------------------------------*/
709
710 // unlink pending rx/tx; completion handlers do all other cleanup
711
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)712 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
713 {
714 unsigned long flags;
715 struct sk_buff *skb;
716 int count = 0;
717
718 spin_lock_irqsave (&q->lock, flags);
719 while (!skb_queue_empty(q)) {
720 struct skb_data *entry;
721 struct urb *urb;
722 int retval;
723
724 skb_queue_walk(q, skb) {
725 entry = (struct skb_data *) skb->cb;
726 if (entry->state != unlink_start)
727 goto found;
728 }
729 break;
730 found:
731 entry->state = unlink_start;
732 urb = entry->urb;
733
734 /*
735 * Get reference count of the URB to avoid it to be
736 * freed during usb_unlink_urb, which may trigger
737 * use-after-free problem inside usb_unlink_urb since
738 * usb_unlink_urb is always racing with .complete
739 * handler(include defer_bh).
740 */
741 usb_get_urb(urb);
742 spin_unlock_irqrestore(&q->lock, flags);
743 // during some PM-driven resume scenarios,
744 // these (async) unlinks complete immediately
745 retval = usb_unlink_urb (urb);
746 if (retval != -EINPROGRESS && retval != 0)
747 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
748 else
749 count++;
750 usb_put_urb(urb);
751 spin_lock_irqsave(&q->lock, flags);
752 }
753 spin_unlock_irqrestore (&q->lock, flags);
754 return count;
755 }
756
757 // Flush all pending rx urbs
758 // minidrivers may need to do this when the MTU changes
759
usbnet_unlink_rx_urbs(struct usbnet * dev)760 void usbnet_unlink_rx_urbs(struct usbnet *dev)
761 {
762 if (netif_running(dev->net)) {
763 (void) unlink_urbs (dev, &dev->rxq);
764 tasklet_schedule(&dev->bh);
765 }
766 }
767 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
768
769 /*-------------------------------------------------------------------------*/
770
wait_skb_queue_empty(struct sk_buff_head * q)771 static void wait_skb_queue_empty(struct sk_buff_head *q)
772 {
773 unsigned long flags;
774
775 spin_lock_irqsave(&q->lock, flags);
776 while (!skb_queue_empty(q)) {
777 spin_unlock_irqrestore(&q->lock, flags);
778 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
779 set_current_state(TASK_UNINTERRUPTIBLE);
780 spin_lock_irqsave(&q->lock, flags);
781 }
782 spin_unlock_irqrestore(&q->lock, flags);
783 }
784
785 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)786 static void usbnet_terminate_urbs(struct usbnet *dev)
787 {
788 DECLARE_WAITQUEUE(wait, current);
789 int temp;
790
791 /* ensure there are no more active urbs */
792 add_wait_queue(&dev->wait, &wait);
793 set_current_state(TASK_UNINTERRUPTIBLE);
794 temp = unlink_urbs(dev, &dev->txq) +
795 unlink_urbs(dev, &dev->rxq);
796
797 /* maybe wait for deletions to finish. */
798 wait_skb_queue_empty(&dev->rxq);
799 wait_skb_queue_empty(&dev->txq);
800 wait_skb_queue_empty(&dev->done);
801 netif_dbg(dev, ifdown, dev->net,
802 "waited for %d urb completions\n", temp);
803 set_current_state(TASK_RUNNING);
804 remove_wait_queue(&dev->wait, &wait);
805 }
806
usbnet_stop(struct net_device * net)807 int usbnet_stop (struct net_device *net)
808 {
809 struct usbnet *dev = netdev_priv(net);
810 const struct driver_info *info = dev->driver_info;
811 int retval, pm, mpn;
812
813 clear_bit(EVENT_DEV_OPEN, &dev->flags);
814 netif_stop_queue (net);
815
816 netif_info(dev, ifdown, dev->net,
817 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
818 net->stats.rx_packets, net->stats.tx_packets,
819 net->stats.rx_errors, net->stats.tx_errors);
820
821 /* to not race resume */
822 pm = usb_autopm_get_interface(dev->intf);
823 /* allow minidriver to stop correctly (wireless devices to turn off
824 * radio etc) */
825 if (info->stop) {
826 retval = info->stop(dev);
827 if (retval < 0)
828 netif_info(dev, ifdown, dev->net,
829 "stop fail (%d) usbnet usb-%s-%s, %s\n",
830 retval,
831 dev->udev->bus->bus_name, dev->udev->devpath,
832 info->description);
833 }
834
835 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
836 usbnet_terminate_urbs(dev);
837
838 usbnet_status_stop(dev);
839
840 usbnet_purge_paused_rxq(dev);
841
842 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
843
844 /* deferred work (timer, softirq, task) must also stop */
845 dev->flags = 0;
846 del_timer_sync (&dev->delay);
847 tasklet_kill (&dev->bh);
848 cancel_work_sync(&dev->kevent);
849 if (!pm)
850 usb_autopm_put_interface(dev->intf);
851
852 if (info->manage_power && mpn)
853 info->manage_power(dev, 0);
854 else
855 usb_autopm_put_interface(dev->intf);
856
857 return 0;
858 }
859 EXPORT_SYMBOL_GPL(usbnet_stop);
860
861 /*-------------------------------------------------------------------------*/
862
863 // posts reads, and enables write queuing
864
865 // precondition: never called in_interrupt
866
usbnet_open(struct net_device * net)867 int usbnet_open (struct net_device *net)
868 {
869 struct usbnet *dev = netdev_priv(net);
870 int retval;
871 const struct driver_info *info = dev->driver_info;
872
873 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
874 netif_info(dev, ifup, dev->net,
875 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
876 retval,
877 dev->udev->bus->bus_name,
878 dev->udev->devpath,
879 info->description);
880 goto done_nopm;
881 }
882
883 // put into "known safe" state
884 if (info->reset && (retval = info->reset (dev)) < 0) {
885 netif_info(dev, ifup, dev->net,
886 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
887 retval,
888 dev->udev->bus->bus_name,
889 dev->udev->devpath,
890 info->description);
891 goto done;
892 }
893
894 /* hard_mtu or rx_urb_size may change in reset() */
895 usbnet_update_max_qlen(dev);
896
897 // insist peer be connected
898 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
899 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
900 goto done;
901 }
902
903 /* start any status interrupt transfer */
904 if (dev->interrupt) {
905 retval = usbnet_status_start(dev, GFP_KERNEL);
906 if (retval < 0) {
907 netif_err(dev, ifup, dev->net,
908 "intr submit %d\n", retval);
909 goto done;
910 }
911 }
912
913 set_bit(EVENT_DEV_OPEN, &dev->flags);
914 netif_start_queue (net);
915 netif_info(dev, ifup, dev->net,
916 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
917 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
918 dev->net->mtu,
919 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
920 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
921 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
922 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
923 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
924 "simple");
925
926 /* reset rx error state */
927 dev->pkt_cnt = 0;
928 dev->pkt_err = 0;
929 clear_bit(EVENT_RX_KILL, &dev->flags);
930
931 // delay posting reads until we're fully open
932 tasklet_schedule (&dev->bh);
933 if (info->manage_power) {
934 retval = info->manage_power(dev, 1);
935 if (retval < 0) {
936 retval = 0;
937 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
938 } else {
939 usb_autopm_put_interface(dev->intf);
940 }
941 }
942 return retval;
943 done:
944 usb_autopm_put_interface(dev->intf);
945 done_nopm:
946 return retval;
947 }
948 EXPORT_SYMBOL_GPL(usbnet_open);
949
950 /*-------------------------------------------------------------------------*/
951
952 /* ethtool methods; minidrivers may need to add some more, but
953 * they'll probably want to use this base set.
954 */
955
956 /* These methods are written on the assumption that the device
957 * uses MII
958 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)959 int usbnet_get_link_ksettings_mii(struct net_device *net,
960 struct ethtool_link_ksettings *cmd)
961 {
962 struct usbnet *dev = netdev_priv(net);
963
964 if (!dev->mii.mdio_read)
965 return -EOPNOTSUPP;
966
967 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
968
969 return 0;
970 }
971 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
972
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)973 int usbnet_get_link_ksettings_internal(struct net_device *net,
974 struct ethtool_link_ksettings *cmd)
975 {
976 struct usbnet *dev = netdev_priv(net);
977
978 /* the assumption that speed is equal on tx and rx
979 * is deeply engrained into the networking layer.
980 * For wireless stuff it is not true.
981 * We assume that rx_speed matters more.
982 */
983 if (dev->rx_speed != SPEED_UNSET)
984 cmd->base.speed = dev->rx_speed / 1000000;
985 else if (dev->tx_speed != SPEED_UNSET)
986 cmd->base.speed = dev->tx_speed / 1000000;
987 else
988 cmd->base.speed = SPEED_UNKNOWN;
989
990 return 0;
991 }
992 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
993
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)994 int usbnet_set_link_ksettings_mii(struct net_device *net,
995 const struct ethtool_link_ksettings *cmd)
996 {
997 struct usbnet *dev = netdev_priv(net);
998 int retval;
999
1000 if (!dev->mii.mdio_write)
1001 return -EOPNOTSUPP;
1002
1003 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1004
1005 /* link speed/duplex might have changed */
1006 if (dev->driver_info->link_reset)
1007 dev->driver_info->link_reset(dev);
1008
1009 /* hard_mtu or rx_urb_size may change in link_reset() */
1010 usbnet_update_max_qlen(dev);
1011
1012 return retval;
1013 }
1014 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1015
usbnet_get_link(struct net_device * net)1016 u32 usbnet_get_link (struct net_device *net)
1017 {
1018 struct usbnet *dev = netdev_priv(net);
1019
1020 /* If a check_connect is defined, return its result */
1021 if (dev->driver_info->check_connect)
1022 return dev->driver_info->check_connect (dev) == 0;
1023
1024 /* if the device has mii operations, use those */
1025 if (dev->mii.mdio_read)
1026 return mii_link_ok(&dev->mii);
1027
1028 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1029 return ethtool_op_get_link(net);
1030 }
1031 EXPORT_SYMBOL_GPL(usbnet_get_link);
1032
usbnet_nway_reset(struct net_device * net)1033 int usbnet_nway_reset(struct net_device *net)
1034 {
1035 struct usbnet *dev = netdev_priv(net);
1036
1037 if (!dev->mii.mdio_write)
1038 return -EOPNOTSUPP;
1039
1040 return mii_nway_restart(&dev->mii);
1041 }
1042 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1043
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1044 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1045 {
1046 struct usbnet *dev = netdev_priv(net);
1047
1048 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1049 strscpy(info->fw_version, dev->driver_info->description,
1050 sizeof(info->fw_version));
1051 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1052 }
1053 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1054
usbnet_get_msglevel(struct net_device * net)1055 u32 usbnet_get_msglevel (struct net_device *net)
1056 {
1057 struct usbnet *dev = netdev_priv(net);
1058
1059 return dev->msg_enable;
1060 }
1061 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1062
usbnet_set_msglevel(struct net_device * net,u32 level)1063 void usbnet_set_msglevel (struct net_device *net, u32 level)
1064 {
1065 struct usbnet *dev = netdev_priv(net);
1066
1067 dev->msg_enable = level;
1068 }
1069 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1070
1071 /* drivers may override default ethtool_ops in their bind() routine */
1072 static const struct ethtool_ops usbnet_ethtool_ops = {
1073 .get_link = usbnet_get_link,
1074 .nway_reset = usbnet_nway_reset,
1075 .get_drvinfo = usbnet_get_drvinfo,
1076 .get_msglevel = usbnet_get_msglevel,
1077 .set_msglevel = usbnet_set_msglevel,
1078 .get_ts_info = ethtool_op_get_ts_info,
1079 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1080 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1081 };
1082
1083 /*-------------------------------------------------------------------------*/
1084
__handle_link_change(struct usbnet * dev)1085 static void __handle_link_change(struct usbnet *dev)
1086 {
1087 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1088 return;
1089
1090 if (!netif_carrier_ok(dev->net)) {
1091 /* kill URBs for reading packets to save bus bandwidth */
1092 unlink_urbs(dev, &dev->rxq);
1093
1094 /*
1095 * tx_timeout will unlink URBs for sending packets and
1096 * tx queue is stopped by netcore after link becomes off
1097 */
1098 } else {
1099 /* submitting URBs for reading packets */
1100 tasklet_schedule(&dev->bh);
1101 }
1102
1103 /* hard_mtu or rx_urb_size may change during link change */
1104 usbnet_update_max_qlen(dev);
1105
1106 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1107 }
1108
usbnet_set_rx_mode(struct net_device * net)1109 void usbnet_set_rx_mode(struct net_device *net)
1110 {
1111 struct usbnet *dev = netdev_priv(net);
1112
1113 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1114 }
1115 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1116
__handle_set_rx_mode(struct usbnet * dev)1117 static void __handle_set_rx_mode(struct usbnet *dev)
1118 {
1119 if (dev->driver_info->set_rx_mode)
1120 (dev->driver_info->set_rx_mode)(dev);
1121
1122 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1123 }
1124
1125 /* work that cannot be done in interrupt context uses keventd.
1126 *
1127 * NOTE: with 2.5 we could do more of this using completion callbacks,
1128 * especially now that control transfers can be queued.
1129 */
1130 static void
usbnet_deferred_kevent(struct work_struct * work)1131 usbnet_deferred_kevent (struct work_struct *work)
1132 {
1133 struct usbnet *dev =
1134 container_of(work, struct usbnet, kevent);
1135 int status;
1136
1137 /* usb_clear_halt() needs a thread context */
1138 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1139 unlink_urbs (dev, &dev->txq);
1140 status = usb_autopm_get_interface(dev->intf);
1141 if (status < 0)
1142 goto fail_pipe;
1143 status = usb_clear_halt (dev->udev, dev->out);
1144 usb_autopm_put_interface(dev->intf);
1145 if (status < 0 &&
1146 status != -EPIPE &&
1147 status != -ESHUTDOWN) {
1148 if (netif_msg_tx_err (dev))
1149 fail_pipe:
1150 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1151 status);
1152 } else {
1153 clear_bit (EVENT_TX_HALT, &dev->flags);
1154 if (status != -ESHUTDOWN)
1155 netif_wake_queue (dev->net);
1156 }
1157 }
1158 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1159 unlink_urbs (dev, &dev->rxq);
1160 status = usb_autopm_get_interface(dev->intf);
1161 if (status < 0)
1162 goto fail_halt;
1163 status = usb_clear_halt (dev->udev, dev->in);
1164 usb_autopm_put_interface(dev->intf);
1165 if (status < 0 &&
1166 status != -EPIPE &&
1167 status != -ESHUTDOWN) {
1168 if (netif_msg_rx_err (dev))
1169 fail_halt:
1170 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1171 status);
1172 } else {
1173 clear_bit (EVENT_RX_HALT, &dev->flags);
1174 tasklet_schedule (&dev->bh);
1175 }
1176 }
1177
1178 /* tasklet could resubmit itself forever if memory is tight */
1179 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1180 struct urb *urb = NULL;
1181 int resched = 1;
1182
1183 if (netif_running (dev->net))
1184 urb = usb_alloc_urb (0, GFP_KERNEL);
1185 else
1186 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1187 if (urb != NULL) {
1188 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1189 status = usb_autopm_get_interface(dev->intf);
1190 if (status < 0) {
1191 usb_free_urb(urb);
1192 goto fail_lowmem;
1193 }
1194 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1195 resched = 0;
1196 usb_autopm_put_interface(dev->intf);
1197 fail_lowmem:
1198 if (resched)
1199 tasklet_schedule (&dev->bh);
1200 }
1201 }
1202
1203 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1204 const struct driver_info *info = dev->driver_info;
1205 int retval = 0;
1206
1207 clear_bit (EVENT_LINK_RESET, &dev->flags);
1208 status = usb_autopm_get_interface(dev->intf);
1209 if (status < 0)
1210 goto skip_reset;
1211 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1212 usb_autopm_put_interface(dev->intf);
1213 skip_reset:
1214 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1215 retval,
1216 dev->udev->bus->bus_name,
1217 dev->udev->devpath,
1218 info->description);
1219 } else {
1220 usb_autopm_put_interface(dev->intf);
1221 }
1222
1223 /* handle link change from link resetting */
1224 __handle_link_change(dev);
1225 }
1226
1227 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1228 __handle_link_change(dev);
1229
1230 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1231 __handle_set_rx_mode(dev);
1232
1233
1234 if (dev->flags)
1235 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1236 }
1237
1238 /*-------------------------------------------------------------------------*/
1239
tx_complete(struct urb * urb)1240 static void tx_complete (struct urb *urb)
1241 {
1242 struct sk_buff *skb = (struct sk_buff *) urb->context;
1243 struct skb_data *entry = (struct skb_data *) skb->cb;
1244 struct usbnet *dev = entry->dev;
1245
1246 if (urb->status == 0) {
1247 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1248 unsigned long flags;
1249
1250 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1251 u64_stats_add(&stats64->tx_packets, entry->packets);
1252 u64_stats_add(&stats64->tx_bytes, entry->length);
1253 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1254 } else {
1255 dev->net->stats.tx_errors++;
1256
1257 switch (urb->status) {
1258 case -EPIPE:
1259 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1260 break;
1261
1262 /* software-driven interface shutdown */
1263 case -ECONNRESET: // async unlink
1264 case -ESHUTDOWN: // hardware gone
1265 break;
1266
1267 /* like rx, tx gets controller i/o faults during hub_wq
1268 * delays and so it uses the same throttling mechanism.
1269 */
1270 case -EPROTO:
1271 case -ETIME:
1272 case -EILSEQ:
1273 usb_mark_last_busy(dev->udev);
1274 if (!timer_pending (&dev->delay)) {
1275 mod_timer (&dev->delay,
1276 jiffies + THROTTLE_JIFFIES);
1277 netif_dbg(dev, link, dev->net,
1278 "tx throttle %d\n", urb->status);
1279 }
1280 netif_stop_queue (dev->net);
1281 break;
1282 default:
1283 netif_dbg(dev, tx_err, dev->net,
1284 "tx err %d\n", entry->urb->status);
1285 break;
1286 }
1287 }
1288
1289 usb_autopm_put_interface_async(dev->intf);
1290 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1291 }
1292
1293 /*-------------------------------------------------------------------------*/
1294
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1295 void usbnet_tx_timeout (struct net_device *net, unsigned int txqueue)
1296 {
1297 struct usbnet *dev = netdev_priv(net);
1298
1299 unlink_urbs (dev, &dev->txq);
1300 tasklet_schedule (&dev->bh);
1301 /* this needs to be handled individually because the generic layer
1302 * doesn't know what is sufficient and could not restore private
1303 * information if a remedy of an unconditional reset were used.
1304 */
1305 if (dev->driver_info->recover)
1306 (dev->driver_info->recover)(dev);
1307 }
1308 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1309
1310 /*-------------------------------------------------------------------------*/
1311
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1312 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1313 {
1314 unsigned num_sgs, total_len = 0;
1315 int i, s = 0;
1316
1317 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1318 if (num_sgs == 1)
1319 return 0;
1320
1321 /* reserve one for zero packet */
1322 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1323 GFP_ATOMIC);
1324 if (!urb->sg)
1325 return -ENOMEM;
1326
1327 urb->num_sgs = num_sgs;
1328 sg_init_table(urb->sg, urb->num_sgs + 1);
1329
1330 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1331 total_len += skb_headlen(skb);
1332
1333 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1334 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1335
1336 total_len += skb_frag_size(f);
1337 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1338 skb_frag_off(f));
1339 }
1340 urb->transfer_buffer_length = total_len;
1341
1342 return 1;
1343 }
1344
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1345 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1346 struct net_device *net)
1347 {
1348 struct usbnet *dev = netdev_priv(net);
1349 unsigned int length;
1350 struct urb *urb = NULL;
1351 struct skb_data *entry;
1352 const struct driver_info *info = dev->driver_info;
1353 unsigned long flags;
1354 int retval;
1355
1356 if (skb)
1357 skb_tx_timestamp(skb);
1358
1359 // some devices want funky USB-level framing, for
1360 // win32 driver (usually) and/or hardware quirks
1361 if (info->tx_fixup) {
1362 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1363 if (!skb) {
1364 /* packet collected; minidriver waiting for more */
1365 if (info->flags & FLAG_MULTI_PACKET)
1366 goto not_drop;
1367 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1368 goto drop;
1369 }
1370 }
1371
1372 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1373 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1374 goto drop;
1375 }
1376
1377 entry = (struct skb_data *) skb->cb;
1378 entry->urb = urb;
1379 entry->dev = dev;
1380
1381 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1382 skb->data, skb->len, tx_complete, skb);
1383 if (dev->can_dma_sg) {
1384 if (build_dma_sg(skb, urb) < 0)
1385 goto drop;
1386 }
1387 length = urb->transfer_buffer_length;
1388
1389 /* don't assume the hardware handles USB_ZERO_PACKET
1390 * NOTE: strictly conforming cdc-ether devices should expect
1391 * the ZLP here, but ignore the one-byte packet.
1392 * NOTE2: CDC NCM specification is different from CDC ECM when
1393 * handling ZLP/short packets, so cdc_ncm driver will make short
1394 * packet itself if needed.
1395 */
1396 if (length % dev->maxpacket == 0) {
1397 if (!(info->flags & FLAG_SEND_ZLP)) {
1398 if (!(info->flags & FLAG_MULTI_PACKET)) {
1399 length++;
1400 if (skb_tailroom(skb) && !urb->num_sgs) {
1401 skb->data[skb->len] = 0;
1402 __skb_put(skb, 1);
1403 } else if (urb->num_sgs)
1404 sg_set_buf(&urb->sg[urb->num_sgs++],
1405 dev->padding_pkt, 1);
1406 }
1407 } else
1408 urb->transfer_flags |= URB_ZERO_PACKET;
1409 }
1410 urb->transfer_buffer_length = length;
1411
1412 if (info->flags & FLAG_MULTI_PACKET) {
1413 /* Driver has set number of packets and a length delta.
1414 * Calculate the complete length and ensure that it's
1415 * positive.
1416 */
1417 entry->length += length;
1418 if (WARN_ON_ONCE(entry->length <= 0))
1419 entry->length = length;
1420 } else {
1421 usbnet_set_skb_tx_stats(skb, 1, length);
1422 }
1423
1424 spin_lock_irqsave(&dev->txq.lock, flags);
1425 retval = usb_autopm_get_interface_async(dev->intf);
1426 if (retval < 0) {
1427 spin_unlock_irqrestore(&dev->txq.lock, flags);
1428 goto drop;
1429 }
1430 if (netif_queue_stopped(net)) {
1431 usb_autopm_put_interface_async(dev->intf);
1432 spin_unlock_irqrestore(&dev->txq.lock, flags);
1433 goto drop;
1434 }
1435
1436 #ifdef CONFIG_PM
1437 /* if this triggers the device is still a sleep */
1438 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1439 /* transmission will be done in resume */
1440 usb_anchor_urb(urb, &dev->deferred);
1441 /* no use to process more packets */
1442 netif_stop_queue(net);
1443 usb_put_urb(urb);
1444 spin_unlock_irqrestore(&dev->txq.lock, flags);
1445 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1446 goto deferred;
1447 }
1448 #endif
1449
1450 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1451 case -EPIPE:
1452 netif_stop_queue (net);
1453 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1454 usb_autopm_put_interface_async(dev->intf);
1455 break;
1456 default:
1457 usb_autopm_put_interface_async(dev->intf);
1458 netif_dbg(dev, tx_err, dev->net,
1459 "tx: submit urb err %d\n", retval);
1460 break;
1461 case 0:
1462 netif_trans_update(net);
1463 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1464 if (dev->txq.qlen >= TX_QLEN (dev))
1465 netif_stop_queue (net);
1466 }
1467 spin_unlock_irqrestore (&dev->txq.lock, flags);
1468
1469 if (retval) {
1470 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1471 drop:
1472 dev->net->stats.tx_dropped++;
1473 not_drop:
1474 if (skb)
1475 dev_kfree_skb_any (skb);
1476 if (urb) {
1477 kfree(urb->sg);
1478 usb_free_urb(urb);
1479 }
1480 } else
1481 netif_dbg(dev, tx_queued, dev->net,
1482 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1483 #ifdef CONFIG_PM
1484 deferred:
1485 #endif
1486 return NETDEV_TX_OK;
1487 }
1488 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1489
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1490 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1491 {
1492 struct urb *urb;
1493 int i;
1494 int ret = 0;
1495
1496 /* don't refill the queue all at once */
1497 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1498 urb = usb_alloc_urb(0, flags);
1499 if (urb != NULL) {
1500 ret = rx_submit(dev, urb, flags);
1501 if (ret)
1502 goto err;
1503 } else {
1504 ret = -ENOMEM;
1505 goto err;
1506 }
1507 }
1508 err:
1509 return ret;
1510 }
1511
usb_free_skb(struct sk_buff * skb)1512 static inline void usb_free_skb(struct sk_buff *skb)
1513 {
1514 struct skb_data *entry = (struct skb_data *)skb->cb;
1515
1516 usb_free_urb(entry->urb);
1517 dev_kfree_skb(skb);
1518 }
1519
1520 /*-------------------------------------------------------------------------*/
1521
1522 // tasklet (work deferred from completions, in_irq) or timer
1523
usbnet_bh(struct timer_list * t)1524 static void usbnet_bh (struct timer_list *t)
1525 {
1526 struct usbnet *dev = from_timer(dev, t, delay);
1527 struct sk_buff *skb;
1528 struct skb_data *entry;
1529
1530 while ((skb = skb_dequeue (&dev->done))) {
1531 entry = (struct skb_data *) skb->cb;
1532 switch (entry->state) {
1533 case rx_done:
1534 if (rx_process(dev, skb))
1535 usb_free_skb(skb);
1536 continue;
1537 case tx_done:
1538 kfree(entry->urb->sg);
1539 fallthrough;
1540 case rx_cleanup:
1541 usb_free_skb(skb);
1542 continue;
1543 default:
1544 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1545 }
1546 }
1547
1548 /* restart RX again after disabling due to high error rate */
1549 clear_bit(EVENT_RX_KILL, &dev->flags);
1550
1551 /* waiting for all pending urbs to complete?
1552 * only then can we forgo submitting anew
1553 */
1554 if (waitqueue_active(&dev->wait)) {
1555 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1556 wake_up_all(&dev->wait);
1557
1558 // or are we maybe short a few urbs?
1559 } else if (netif_running (dev->net) &&
1560 netif_device_present (dev->net) &&
1561 netif_carrier_ok(dev->net) &&
1562 !timer_pending(&dev->delay) &&
1563 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1564 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1565 int temp = dev->rxq.qlen;
1566
1567 if (temp < RX_QLEN(dev)) {
1568 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1569 return;
1570 if (temp != dev->rxq.qlen)
1571 netif_dbg(dev, link, dev->net,
1572 "rxqlen %d --> %d\n",
1573 temp, dev->rxq.qlen);
1574 if (dev->rxq.qlen < RX_QLEN(dev))
1575 tasklet_schedule (&dev->bh);
1576 }
1577 if (dev->txq.qlen < TX_QLEN (dev))
1578 netif_wake_queue (dev->net);
1579 }
1580 }
1581
usbnet_bh_tasklet(struct tasklet_struct * t)1582 static void usbnet_bh_tasklet(struct tasklet_struct *t)
1583 {
1584 struct usbnet *dev = from_tasklet(dev, t, bh);
1585
1586 usbnet_bh(&dev->delay);
1587 }
1588
1589
1590 /*-------------------------------------------------------------------------
1591 *
1592 * USB Device Driver support
1593 *
1594 *-------------------------------------------------------------------------*/
1595
1596 // precondition: never called in_interrupt
1597
usbnet_disconnect(struct usb_interface * intf)1598 void usbnet_disconnect (struct usb_interface *intf)
1599 {
1600 struct usbnet *dev;
1601 struct usb_device *xdev;
1602 struct net_device *net;
1603 struct urb *urb;
1604
1605 dev = usb_get_intfdata(intf);
1606 usb_set_intfdata(intf, NULL);
1607 if (!dev)
1608 return;
1609
1610 xdev = interface_to_usbdev (intf);
1611
1612 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1613 intf->dev.driver->name,
1614 xdev->bus->bus_name, xdev->devpath,
1615 dev->driver_info->description);
1616
1617 net = dev->net;
1618 unregister_netdev (net);
1619
1620 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1621 dev_kfree_skb(urb->context);
1622 kfree(urb->sg);
1623 usb_free_urb(urb);
1624 }
1625
1626 if (dev->driver_info->unbind)
1627 dev->driver_info->unbind(dev, intf);
1628
1629 usb_kill_urb(dev->interrupt);
1630 usb_free_urb(dev->interrupt);
1631 kfree(dev->padding_pkt);
1632
1633 free_percpu(net->tstats);
1634 free_netdev(net);
1635 }
1636 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1637
1638 static const struct net_device_ops usbnet_netdev_ops = {
1639 .ndo_open = usbnet_open,
1640 .ndo_stop = usbnet_stop,
1641 .ndo_start_xmit = usbnet_start_xmit,
1642 .ndo_tx_timeout = usbnet_tx_timeout,
1643 .ndo_set_rx_mode = usbnet_set_rx_mode,
1644 .ndo_change_mtu = usbnet_change_mtu,
1645 .ndo_get_stats64 = dev_get_tstats64,
1646 .ndo_set_mac_address = eth_mac_addr,
1647 .ndo_validate_addr = eth_validate_addr,
1648 };
1649
1650 /*-------------------------------------------------------------------------*/
1651
1652 // precondition: never called in_interrupt
1653
1654 static struct device_type wlan_type = {
1655 .name = "wlan",
1656 };
1657
1658 static struct device_type wwan_type = {
1659 .name = "wwan",
1660 };
1661
1662 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1663 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1664 {
1665 struct usbnet *dev;
1666 struct net_device *net;
1667 struct usb_host_interface *interface;
1668 const struct driver_info *info;
1669 struct usb_device *xdev;
1670 int status;
1671 const char *name;
1672 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1673
1674 /* usbnet already took usb runtime pm, so have to enable the feature
1675 * for usb interface, otherwise usb_autopm_get_interface may return
1676 * failure if RUNTIME_PM is enabled.
1677 */
1678 if (!driver->supports_autosuspend) {
1679 driver->supports_autosuspend = 1;
1680 pm_runtime_enable(&udev->dev);
1681 }
1682
1683 name = udev->dev.driver->name;
1684 info = (const struct driver_info *) prod->driver_info;
1685 if (!info) {
1686 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1687 return -ENODEV;
1688 }
1689 xdev = interface_to_usbdev (udev);
1690 interface = udev->cur_altsetting;
1691
1692 status = -ENOMEM;
1693
1694 // set up our own records
1695 net = alloc_etherdev(sizeof(*dev));
1696 if (!net)
1697 goto out;
1698
1699 /* netdev_printk() needs this so do it as early as possible */
1700 SET_NETDEV_DEV(net, &udev->dev);
1701
1702 dev = netdev_priv(net);
1703 dev->udev = xdev;
1704 dev->intf = udev;
1705 dev->driver_info = info;
1706 dev->driver_name = name;
1707 dev->rx_speed = SPEED_UNSET;
1708 dev->tx_speed = SPEED_UNSET;
1709
1710 net->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1711 if (!net->tstats)
1712 goto out0;
1713
1714 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1715 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1716 init_waitqueue_head(&dev->wait);
1717 skb_queue_head_init (&dev->rxq);
1718 skb_queue_head_init (&dev->txq);
1719 skb_queue_head_init (&dev->done);
1720 skb_queue_head_init(&dev->rxq_pause);
1721 tasklet_setup(&dev->bh, usbnet_bh_tasklet);
1722 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1723 init_usb_anchor(&dev->deferred);
1724 timer_setup(&dev->delay, usbnet_bh, 0);
1725 mutex_init (&dev->phy_mutex);
1726 mutex_init(&dev->interrupt_mutex);
1727 dev->interrupt_count = 0;
1728
1729 dev->net = net;
1730 strscpy(net->name, "usb%d", sizeof(net->name));
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);
1798 if (dev->maxpacket == 0) {
1799 /* that is a broken device */
1800 status = -ENODEV;
1801 goto out4;
1802 }
1803
1804 /* this flags the device for user space */
1805 if (!is_valid_ether_addr(net->dev_addr))
1806 eth_hw_addr_random(net);
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 return 0;
2217 }
2218 module_init(usbnet_init);
2219
usbnet_exit(void)2220 static void __exit usbnet_exit(void)
2221 {
2222 }
2223 module_exit(usbnet_exit);
2224
2225 MODULE_AUTHOR("David Brownell");
2226 MODULE_DESCRIPTION("USB network driver framework");
2227 MODULE_LICENSE("GPL");
2228