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