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 int 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 return -EPROTO;
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 return -EALREADY;
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 return -EPROTO;
578 }
579
580 usbnet_skb_return(dev, skb);
581 return 0;
582 }
583
584 /*-------------------------------------------------------------------------*/
585
rx_complete(struct urb * urb)586 static void rx_complete (struct urb *urb)
587 {
588 struct sk_buff *skb = (struct sk_buff *) urb->context;
589 struct skb_data *entry = (struct skb_data *) skb->cb;
590 struct usbnet *dev = entry->dev;
591 int urb_status = urb->status;
592 enum skb_state state;
593
594 skb_put (skb, urb->actual_length);
595 state = rx_done;
596 entry->urb = NULL;
597
598 switch (urb_status) {
599 /* success */
600 case 0:
601 break;
602
603 /* stalls need manual reset. this is rare ... except that
604 * when going through USB 2.0 TTs, unplug appears this way.
605 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
606 * storm, recovering as needed.
607 */
608 case -EPIPE:
609 dev->net->stats.rx_errors++;
610 usbnet_defer_kevent (dev, EVENT_RX_HALT);
611 fallthrough;
612
613 /* software-driven interface shutdown */
614 case -ECONNRESET: /* async unlink */
615 case -ESHUTDOWN: /* hardware gone */
616 netif_dbg(dev, ifdown, dev->net,
617 "rx shutdown, code %d\n", urb_status);
618 goto block;
619
620 /* we get controller i/o faults during hub_wq disconnect() delays.
621 * throttle down resubmits, to avoid log floods; just temporarily,
622 * so we still recover when the fault isn't a hub_wq delay.
623 */
624 case -EPROTO:
625 case -ETIME:
626 case -EILSEQ:
627 dev->net->stats.rx_errors++;
628 if (!timer_pending (&dev->delay)) {
629 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
630 netif_dbg(dev, link, dev->net,
631 "rx throttle %d\n", urb_status);
632 }
633 block:
634 state = rx_cleanup;
635 entry->urb = urb;
636 urb = NULL;
637 break;
638
639 /* data overrun ... flush fifo? */
640 case -EOVERFLOW:
641 dev->net->stats.rx_over_errors++;
642 fallthrough;
643
644 default:
645 state = rx_cleanup;
646 dev->net->stats.rx_errors++;
647 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
648 break;
649 }
650
651 /* stop rx if packet error rate is high */
652 if (++dev->pkt_cnt > 30) {
653 dev->pkt_cnt = 0;
654 dev->pkt_err = 0;
655 } else {
656 if (state == rx_cleanup)
657 dev->pkt_err++;
658 if (dev->pkt_err > 20)
659 set_bit(EVENT_RX_KILL, &dev->flags);
660 }
661
662 state = defer_bh(dev, skb, &dev->rxq, state);
663
664 if (urb) {
665 if (netif_running (dev->net) &&
666 !test_bit (EVENT_RX_HALT, &dev->flags) &&
667 state != unlink_start) {
668 rx_submit (dev, urb, GFP_ATOMIC);
669 usb_mark_last_busy(dev->udev);
670 return;
671 }
672 usb_free_urb (urb);
673 }
674 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
675 }
676
677 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)678 void usbnet_pause_rx(struct usbnet *dev)
679 {
680 set_bit(EVENT_RX_PAUSED, &dev->flags);
681
682 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
683 }
684 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
685
usbnet_resume_rx(struct usbnet * dev)686 void usbnet_resume_rx(struct usbnet *dev)
687 {
688 struct sk_buff *skb;
689 int num = 0;
690
691 clear_bit(EVENT_RX_PAUSED, &dev->flags);
692
693 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
694 usbnet_skb_return(dev, skb);
695 num++;
696 }
697
698 tasklet_schedule(&dev->bh);
699
700 netif_dbg(dev, rx_status, dev->net,
701 "paused rx queue disabled, %d skbs requeued\n", num);
702 }
703 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
704
usbnet_purge_paused_rxq(struct usbnet * dev)705 void usbnet_purge_paused_rxq(struct usbnet *dev)
706 {
707 skb_queue_purge(&dev->rxq_pause);
708 }
709 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
710
711 /*-------------------------------------------------------------------------*/
712
713 // unlink pending rx/tx; completion handlers do all other cleanup
714
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)715 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
716 {
717 unsigned long flags;
718 struct sk_buff *skb;
719 int count = 0;
720
721 spin_lock_irqsave (&q->lock, flags);
722 while (!skb_queue_empty(q)) {
723 struct skb_data *entry;
724 struct urb *urb;
725 int retval;
726
727 skb_queue_walk(q, skb) {
728 entry = (struct skb_data *) skb->cb;
729 if (entry->state != unlink_start)
730 goto found;
731 }
732 break;
733 found:
734 entry->state = unlink_start;
735 urb = entry->urb;
736
737 /*
738 * Get reference count of the URB to avoid it to be
739 * freed during usb_unlink_urb, which may trigger
740 * use-after-free problem inside usb_unlink_urb since
741 * usb_unlink_urb is always racing with .complete
742 * handler(include defer_bh).
743 */
744 usb_get_urb(urb);
745 spin_unlock_irqrestore(&q->lock, flags);
746 // during some PM-driven resume scenarios,
747 // these (async) unlinks complete immediately
748 retval = usb_unlink_urb (urb);
749 if (retval != -EINPROGRESS && retval != 0)
750 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
751 else
752 count++;
753 usb_put_urb(urb);
754 spin_lock_irqsave(&q->lock, flags);
755 }
756 spin_unlock_irqrestore (&q->lock, flags);
757 return count;
758 }
759
760 // Flush all pending rx urbs
761 // minidrivers may need to do this when the MTU changes
762
usbnet_unlink_rx_urbs(struct usbnet * dev)763 void usbnet_unlink_rx_urbs(struct usbnet *dev)
764 {
765 if (netif_running(dev->net)) {
766 (void) unlink_urbs (dev, &dev->rxq);
767 tasklet_schedule(&dev->bh);
768 }
769 }
770 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
771
772 /*-------------------------------------------------------------------------*/
773
wait_skb_queue_empty(struct sk_buff_head * q)774 static void wait_skb_queue_empty(struct sk_buff_head *q)
775 {
776 unsigned long flags;
777
778 spin_lock_irqsave(&q->lock, flags);
779 while (!skb_queue_empty(q)) {
780 spin_unlock_irqrestore(&q->lock, flags);
781 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
782 set_current_state(TASK_UNINTERRUPTIBLE);
783 spin_lock_irqsave(&q->lock, flags);
784 }
785 spin_unlock_irqrestore(&q->lock, flags);
786 }
787
788 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)789 static void usbnet_terminate_urbs(struct usbnet *dev)
790 {
791 DECLARE_WAITQUEUE(wait, current);
792 int temp;
793
794 /* ensure there are no more active urbs */
795 add_wait_queue(&dev->wait, &wait);
796 set_current_state(TASK_UNINTERRUPTIBLE);
797 temp = unlink_urbs(dev, &dev->txq) +
798 unlink_urbs(dev, &dev->rxq);
799
800 /* maybe wait for deletions to finish. */
801 wait_skb_queue_empty(&dev->rxq);
802 wait_skb_queue_empty(&dev->txq);
803 wait_skb_queue_empty(&dev->done);
804 netif_dbg(dev, ifdown, dev->net,
805 "waited for %d urb completions\n", temp);
806 set_current_state(TASK_RUNNING);
807 remove_wait_queue(&dev->wait, &wait);
808 }
809
usbnet_stop(struct net_device * net)810 int usbnet_stop (struct net_device *net)
811 {
812 struct usbnet *dev = netdev_priv(net);
813 const struct driver_info *info = dev->driver_info;
814 int retval, pm, mpn;
815
816 clear_bit(EVENT_DEV_OPEN, &dev->flags);
817 netif_stop_queue (net);
818
819 netif_info(dev, ifdown, dev->net,
820 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
821 net->stats.rx_packets, net->stats.tx_packets,
822 net->stats.rx_errors, net->stats.tx_errors);
823
824 /* to not race resume */
825 pm = usb_autopm_get_interface(dev->intf);
826 /* allow minidriver to stop correctly (wireless devices to turn off
827 * radio etc) */
828 if (info->stop) {
829 retval = info->stop(dev);
830 if (retval < 0)
831 netif_info(dev, ifdown, dev->net,
832 "stop fail (%d) usbnet usb-%s-%s, %s\n",
833 retval,
834 dev->udev->bus->bus_name, dev->udev->devpath,
835 info->description);
836 }
837
838 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
839 usbnet_terminate_urbs(dev);
840
841 usbnet_status_stop(dev);
842
843 usbnet_purge_paused_rxq(dev);
844
845 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
846
847 /* deferred work (timer, softirq, task) must also stop */
848 dev->flags = 0;
849 del_timer_sync (&dev->delay);
850 tasklet_kill (&dev->bh);
851 cancel_work_sync(&dev->kevent);
852 if (!pm)
853 usb_autopm_put_interface(dev->intf);
854
855 if (info->manage_power && mpn)
856 info->manage_power(dev, 0);
857 else
858 usb_autopm_put_interface(dev->intf);
859
860 return 0;
861 }
862 EXPORT_SYMBOL_GPL(usbnet_stop);
863
864 /*-------------------------------------------------------------------------*/
865
866 // posts reads, and enables write queuing
867
868 // precondition: never called in_interrupt
869
usbnet_open(struct net_device * net)870 int usbnet_open (struct net_device *net)
871 {
872 struct usbnet *dev = netdev_priv(net);
873 int retval;
874 const struct driver_info *info = dev->driver_info;
875
876 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
877 netif_info(dev, ifup, dev->net,
878 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
879 retval,
880 dev->udev->bus->bus_name,
881 dev->udev->devpath,
882 info->description);
883 goto done_nopm;
884 }
885
886 // put into "known safe" state
887 if (info->reset && (retval = info->reset (dev)) < 0) {
888 netif_info(dev, ifup, dev->net,
889 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
890 retval,
891 dev->udev->bus->bus_name,
892 dev->udev->devpath,
893 info->description);
894 goto done;
895 }
896
897 /* hard_mtu or rx_urb_size may change in reset() */
898 usbnet_update_max_qlen(dev);
899
900 // insist peer be connected
901 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
902 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
903 goto done;
904 }
905
906 /* start any status interrupt transfer */
907 if (dev->interrupt) {
908 retval = usbnet_status_start(dev, GFP_KERNEL);
909 if (retval < 0) {
910 netif_err(dev, ifup, dev->net,
911 "intr submit %d\n", retval);
912 goto done;
913 }
914 }
915
916 set_bit(EVENT_DEV_OPEN, &dev->flags);
917 netif_start_queue (net);
918 netif_info(dev, ifup, dev->net,
919 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
920 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
921 dev->net->mtu,
922 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
923 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
924 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
925 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
926 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
927 "simple");
928
929 /* reset rx error state */
930 dev->pkt_cnt = 0;
931 dev->pkt_err = 0;
932 clear_bit(EVENT_RX_KILL, &dev->flags);
933
934 // delay posting reads until we're fully open
935 tasklet_schedule (&dev->bh);
936 if (info->manage_power) {
937 retval = info->manage_power(dev, 1);
938 if (retval < 0) {
939 retval = 0;
940 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
941 } else {
942 usb_autopm_put_interface(dev->intf);
943 }
944 }
945 return retval;
946 done:
947 usb_autopm_put_interface(dev->intf);
948 done_nopm:
949 return retval;
950 }
951 EXPORT_SYMBOL_GPL(usbnet_open);
952
953 /*-------------------------------------------------------------------------*/
954
955 /* ethtool methods; minidrivers may need to add some more, but
956 * they'll probably want to use this base set.
957 */
958
959 /* These methods are written on the assumption that the device
960 * uses MII
961 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)962 int usbnet_get_link_ksettings_mii(struct net_device *net,
963 struct ethtool_link_ksettings *cmd)
964 {
965 struct usbnet *dev = netdev_priv(net);
966
967 if (!dev->mii.mdio_read)
968 return -EOPNOTSUPP;
969
970 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
971
972 return 0;
973 }
974 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
975
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)976 int usbnet_get_link_ksettings_internal(struct net_device *net,
977 struct ethtool_link_ksettings *cmd)
978 {
979 struct usbnet *dev = netdev_priv(net);
980
981 /* the assumption that speed is equal on tx and rx
982 * is deeply engrained into the networking layer.
983 * For wireless stuff it is not true.
984 * We assume that rx_speed matters more.
985 */
986 if (dev->rx_speed != SPEED_UNSET)
987 cmd->base.speed = dev->rx_speed / 1000000;
988 else if (dev->tx_speed != SPEED_UNSET)
989 cmd->base.speed = dev->tx_speed / 1000000;
990 else
991 cmd->base.speed = SPEED_UNKNOWN;
992
993 return 0;
994 }
995 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
996
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)997 int usbnet_set_link_ksettings_mii(struct net_device *net,
998 const struct ethtool_link_ksettings *cmd)
999 {
1000 struct usbnet *dev = netdev_priv(net);
1001 int retval;
1002
1003 if (!dev->mii.mdio_write)
1004 return -EOPNOTSUPP;
1005
1006 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1007
1008 /* link speed/duplex might have changed */
1009 if (dev->driver_info->link_reset)
1010 dev->driver_info->link_reset(dev);
1011
1012 /* hard_mtu or rx_urb_size may change in link_reset() */
1013 usbnet_update_max_qlen(dev);
1014
1015 return retval;
1016 }
1017 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1018
usbnet_get_link(struct net_device * net)1019 u32 usbnet_get_link (struct net_device *net)
1020 {
1021 struct usbnet *dev = netdev_priv(net);
1022
1023 /* If a check_connect is defined, return its result */
1024 if (dev->driver_info->check_connect)
1025 return dev->driver_info->check_connect (dev) == 0;
1026
1027 /* if the device has mii operations, use those */
1028 if (dev->mii.mdio_read)
1029 return mii_link_ok(&dev->mii);
1030
1031 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1032 return ethtool_op_get_link(net);
1033 }
1034 EXPORT_SYMBOL_GPL(usbnet_get_link);
1035
usbnet_nway_reset(struct net_device * net)1036 int usbnet_nway_reset(struct net_device *net)
1037 {
1038 struct usbnet *dev = netdev_priv(net);
1039
1040 if (!dev->mii.mdio_write)
1041 return -EOPNOTSUPP;
1042
1043 return mii_nway_restart(&dev->mii);
1044 }
1045 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1046
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1047 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1048 {
1049 struct usbnet *dev = netdev_priv(net);
1050
1051 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1052 strscpy(info->fw_version, dev->driver_info->description,
1053 sizeof(info->fw_version));
1054 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1055 }
1056 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1057
usbnet_get_msglevel(struct net_device * net)1058 u32 usbnet_get_msglevel (struct net_device *net)
1059 {
1060 struct usbnet *dev = netdev_priv(net);
1061
1062 return dev->msg_enable;
1063 }
1064 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1065
usbnet_set_msglevel(struct net_device * net,u32 level)1066 void usbnet_set_msglevel (struct net_device *net, u32 level)
1067 {
1068 struct usbnet *dev = netdev_priv(net);
1069
1070 dev->msg_enable = level;
1071 }
1072 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1073
1074 /* drivers may override default ethtool_ops in their bind() routine */
1075 static const struct ethtool_ops usbnet_ethtool_ops = {
1076 .get_link = usbnet_get_link,
1077 .nway_reset = usbnet_nway_reset,
1078 .get_drvinfo = usbnet_get_drvinfo,
1079 .get_msglevel = usbnet_get_msglevel,
1080 .set_msglevel = usbnet_set_msglevel,
1081 .get_ts_info = ethtool_op_get_ts_info,
1082 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1083 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1084 };
1085
1086 /*-------------------------------------------------------------------------*/
1087
__handle_link_change(struct usbnet * dev)1088 static void __handle_link_change(struct usbnet *dev)
1089 {
1090 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1091 return;
1092
1093 if (!netif_carrier_ok(dev->net)) {
1094 /* kill URBs for reading packets to save bus bandwidth */
1095 unlink_urbs(dev, &dev->rxq);
1096
1097 /*
1098 * tx_timeout will unlink URBs for sending packets and
1099 * tx queue is stopped by netcore after link becomes off
1100 */
1101 } else {
1102 /* submitting URBs for reading packets */
1103 tasklet_schedule(&dev->bh);
1104 }
1105
1106 /* hard_mtu or rx_urb_size may change during link change */
1107 usbnet_update_max_qlen(dev);
1108
1109 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1110 }
1111
usbnet_set_rx_mode(struct net_device * net)1112 void usbnet_set_rx_mode(struct net_device *net)
1113 {
1114 struct usbnet *dev = netdev_priv(net);
1115
1116 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1117 }
1118 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1119
__handle_set_rx_mode(struct usbnet * dev)1120 static void __handle_set_rx_mode(struct usbnet *dev)
1121 {
1122 if (dev->driver_info->set_rx_mode)
1123 (dev->driver_info->set_rx_mode)(dev);
1124
1125 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1126 }
1127
1128 /* work that cannot be done in interrupt context uses keventd.
1129 *
1130 * NOTE: with 2.5 we could do more of this using completion callbacks,
1131 * especially now that control transfers can be queued.
1132 */
1133 static void
usbnet_deferred_kevent(struct work_struct * work)1134 usbnet_deferred_kevent (struct work_struct *work)
1135 {
1136 struct usbnet *dev =
1137 container_of(work, struct usbnet, kevent);
1138 int status;
1139
1140 /* usb_clear_halt() needs a thread context */
1141 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1142 unlink_urbs (dev, &dev->txq);
1143 status = usb_autopm_get_interface(dev->intf);
1144 if (status < 0)
1145 goto fail_pipe;
1146 status = usb_clear_halt (dev->udev, dev->out);
1147 usb_autopm_put_interface(dev->intf);
1148 if (status < 0 &&
1149 status != -EPIPE &&
1150 status != -ESHUTDOWN) {
1151 if (netif_msg_tx_err (dev))
1152 fail_pipe:
1153 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1154 status);
1155 } else {
1156 clear_bit (EVENT_TX_HALT, &dev->flags);
1157 if (status != -ESHUTDOWN)
1158 netif_wake_queue (dev->net);
1159 }
1160 }
1161 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1162 unlink_urbs (dev, &dev->rxq);
1163 status = usb_autopm_get_interface(dev->intf);
1164 if (status < 0)
1165 goto fail_halt;
1166 status = usb_clear_halt (dev->udev, dev->in);
1167 usb_autopm_put_interface(dev->intf);
1168 if (status < 0 &&
1169 status != -EPIPE &&
1170 status != -ESHUTDOWN) {
1171 if (netif_msg_rx_err (dev))
1172 fail_halt:
1173 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1174 status);
1175 } else {
1176 clear_bit (EVENT_RX_HALT, &dev->flags);
1177 tasklet_schedule (&dev->bh);
1178 }
1179 }
1180
1181 /* tasklet could resubmit itself forever if memory is tight */
1182 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1183 struct urb *urb = NULL;
1184 int resched = 1;
1185
1186 if (netif_running (dev->net))
1187 urb = usb_alloc_urb (0, GFP_KERNEL);
1188 else
1189 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1190 if (urb != NULL) {
1191 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1192 status = usb_autopm_get_interface(dev->intf);
1193 if (status < 0) {
1194 usb_free_urb(urb);
1195 goto fail_lowmem;
1196 }
1197 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1198 resched = 0;
1199 usb_autopm_put_interface(dev->intf);
1200 fail_lowmem:
1201 if (resched)
1202 tasklet_schedule (&dev->bh);
1203 }
1204 }
1205
1206 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1207 const struct driver_info *info = dev->driver_info;
1208 int retval = 0;
1209
1210 clear_bit (EVENT_LINK_RESET, &dev->flags);
1211 status = usb_autopm_get_interface(dev->intf);
1212 if (status < 0)
1213 goto skip_reset;
1214 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1215 usb_autopm_put_interface(dev->intf);
1216 skip_reset:
1217 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1218 retval,
1219 dev->udev->bus->bus_name,
1220 dev->udev->devpath,
1221 info->description);
1222 } else {
1223 usb_autopm_put_interface(dev->intf);
1224 }
1225
1226 /* handle link change from link resetting */
1227 __handle_link_change(dev);
1228 }
1229
1230 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1231 __handle_link_change(dev);
1232
1233 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1234 __handle_set_rx_mode(dev);
1235
1236
1237 if (dev->flags)
1238 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1239 }
1240
1241 /*-------------------------------------------------------------------------*/
1242
tx_complete(struct urb * urb)1243 static void tx_complete (struct urb *urb)
1244 {
1245 struct sk_buff *skb = (struct sk_buff *) urb->context;
1246 struct skb_data *entry = (struct skb_data *) skb->cb;
1247 struct usbnet *dev = entry->dev;
1248
1249 if (urb->status == 0) {
1250 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1251 unsigned long flags;
1252
1253 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1254 u64_stats_add(&stats64->tx_packets, entry->packets);
1255 u64_stats_add(&stats64->tx_bytes, entry->length);
1256 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1257 } else {
1258 dev->net->stats.tx_errors++;
1259
1260 switch (urb->status) {
1261 case -EPIPE:
1262 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1263 break;
1264
1265 /* software-driven interface shutdown */
1266 case -ECONNRESET: // async unlink
1267 case -ESHUTDOWN: // hardware gone
1268 break;
1269
1270 /* like rx, tx gets controller i/o faults during hub_wq
1271 * delays and so it uses the same throttling mechanism.
1272 */
1273 case -EPROTO:
1274 case -ETIME:
1275 case -EILSEQ:
1276 usb_mark_last_busy(dev->udev);
1277 if (!timer_pending (&dev->delay)) {
1278 mod_timer (&dev->delay,
1279 jiffies + THROTTLE_JIFFIES);
1280 netif_dbg(dev, link, dev->net,
1281 "tx throttle %d\n", urb->status);
1282 }
1283 netif_stop_queue (dev->net);
1284 break;
1285 default:
1286 netif_dbg(dev, tx_err, dev->net,
1287 "tx err %d\n", entry->urb->status);
1288 break;
1289 }
1290 }
1291
1292 usb_autopm_put_interface_async(dev->intf);
1293 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1294 }
1295
1296 /*-------------------------------------------------------------------------*/
1297
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1298 void usbnet_tx_timeout (struct net_device *net, unsigned int txqueue)
1299 {
1300 struct usbnet *dev = netdev_priv(net);
1301
1302 unlink_urbs (dev, &dev->txq);
1303 tasklet_schedule (&dev->bh);
1304 /* this needs to be handled individually because the generic layer
1305 * doesn't know what is sufficient and could not restore private
1306 * information if a remedy of an unconditional reset were used.
1307 */
1308 if (dev->driver_info->recover)
1309 (dev->driver_info->recover)(dev);
1310 }
1311 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1312
1313 /*-------------------------------------------------------------------------*/
1314
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1315 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1316 {
1317 unsigned num_sgs, total_len = 0;
1318 int i, s = 0;
1319
1320 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1321 if (num_sgs == 1)
1322 return 0;
1323
1324 /* reserve one for zero packet */
1325 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1326 GFP_ATOMIC);
1327 if (!urb->sg)
1328 return -ENOMEM;
1329
1330 urb->num_sgs = num_sgs;
1331 sg_init_table(urb->sg, urb->num_sgs + 1);
1332
1333 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1334 total_len += skb_headlen(skb);
1335
1336 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1337 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1338
1339 total_len += skb_frag_size(f);
1340 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1341 skb_frag_off(f));
1342 }
1343 urb->transfer_buffer_length = total_len;
1344
1345 return 1;
1346 }
1347
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1348 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1349 struct net_device *net)
1350 {
1351 struct usbnet *dev = netdev_priv(net);
1352 unsigned int length;
1353 struct urb *urb = NULL;
1354 struct skb_data *entry;
1355 const struct driver_info *info = dev->driver_info;
1356 unsigned long flags;
1357 int retval;
1358
1359 if (skb)
1360 skb_tx_timestamp(skb);
1361
1362 // some devices want funky USB-level framing, for
1363 // win32 driver (usually) and/or hardware quirks
1364 if (info->tx_fixup) {
1365 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1366 if (!skb) {
1367 /* packet collected; minidriver waiting for more */
1368 if (info->flags & FLAG_MULTI_PACKET)
1369 goto not_drop;
1370 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1371 goto drop;
1372 }
1373 }
1374
1375 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1376 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1377 goto drop;
1378 }
1379
1380 entry = (struct skb_data *) skb->cb;
1381 entry->urb = urb;
1382 entry->dev = dev;
1383
1384 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1385 skb->data, skb->len, tx_complete, skb);
1386 if (dev->can_dma_sg) {
1387 if (build_dma_sg(skb, urb) < 0)
1388 goto drop;
1389 }
1390 length = urb->transfer_buffer_length;
1391
1392 /* don't assume the hardware handles USB_ZERO_PACKET
1393 * NOTE: strictly conforming cdc-ether devices should expect
1394 * the ZLP here, but ignore the one-byte packet.
1395 * NOTE2: CDC NCM specification is different from CDC ECM when
1396 * handling ZLP/short packets, so cdc_ncm driver will make short
1397 * packet itself if needed.
1398 */
1399 if (length % dev->maxpacket == 0) {
1400 if (!(info->flags & FLAG_SEND_ZLP)) {
1401 if (!(info->flags & FLAG_MULTI_PACKET)) {
1402 length++;
1403 if (skb_tailroom(skb) && !urb->num_sgs) {
1404 skb->data[skb->len] = 0;
1405 __skb_put(skb, 1);
1406 } else if (urb->num_sgs)
1407 sg_set_buf(&urb->sg[urb->num_sgs++],
1408 dev->padding_pkt, 1);
1409 }
1410 } else
1411 urb->transfer_flags |= URB_ZERO_PACKET;
1412 }
1413 urb->transfer_buffer_length = length;
1414
1415 if (info->flags & FLAG_MULTI_PACKET) {
1416 /* Driver has set number of packets and a length delta.
1417 * Calculate the complete length and ensure that it's
1418 * positive.
1419 */
1420 entry->length += length;
1421 if (WARN_ON_ONCE(entry->length <= 0))
1422 entry->length = length;
1423 } else {
1424 usbnet_set_skb_tx_stats(skb, 1, length);
1425 }
1426
1427 spin_lock_irqsave(&dev->txq.lock, flags);
1428 retval = usb_autopm_get_interface_async(dev->intf);
1429 if (retval < 0) {
1430 spin_unlock_irqrestore(&dev->txq.lock, flags);
1431 goto drop;
1432 }
1433 if (netif_queue_stopped(net)) {
1434 usb_autopm_put_interface_async(dev->intf);
1435 spin_unlock_irqrestore(&dev->txq.lock, flags);
1436 goto drop;
1437 }
1438
1439 #ifdef CONFIG_PM
1440 /* if this triggers the device is still a sleep */
1441 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1442 /* transmission will be done in resume */
1443 usb_anchor_urb(urb, &dev->deferred);
1444 /* no use to process more packets */
1445 netif_stop_queue(net);
1446 usb_put_urb(urb);
1447 spin_unlock_irqrestore(&dev->txq.lock, flags);
1448 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1449 goto deferred;
1450 }
1451 #endif
1452
1453 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1454 case -EPIPE:
1455 netif_stop_queue (net);
1456 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1457 usb_autopm_put_interface_async(dev->intf);
1458 break;
1459 default:
1460 usb_autopm_put_interface_async(dev->intf);
1461 netif_dbg(dev, tx_err, dev->net,
1462 "tx: submit urb err %d\n", retval);
1463 break;
1464 case 0:
1465 netif_trans_update(net);
1466 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1467 if (dev->txq.qlen >= TX_QLEN (dev))
1468 netif_stop_queue (net);
1469 }
1470 spin_unlock_irqrestore (&dev->txq.lock, flags);
1471
1472 if (retval) {
1473 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1474 drop:
1475 dev->net->stats.tx_dropped++;
1476 not_drop:
1477 if (skb)
1478 dev_kfree_skb_any (skb);
1479 if (urb) {
1480 kfree(urb->sg);
1481 usb_free_urb(urb);
1482 }
1483 } else
1484 netif_dbg(dev, tx_queued, dev->net,
1485 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1486 #ifdef CONFIG_PM
1487 deferred:
1488 #endif
1489 return NETDEV_TX_OK;
1490 }
1491 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1492
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1493 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1494 {
1495 struct urb *urb;
1496 int i;
1497 int ret = 0;
1498
1499 /* don't refill the queue all at once */
1500 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1501 urb = usb_alloc_urb(0, flags);
1502 if (urb != NULL) {
1503 ret = rx_submit(dev, urb, flags);
1504 if (ret)
1505 goto err;
1506 } else {
1507 ret = -ENOMEM;
1508 goto err;
1509 }
1510 }
1511 err:
1512 return ret;
1513 }
1514
usb_free_skb(struct sk_buff * skb)1515 static inline void usb_free_skb(struct sk_buff *skb)
1516 {
1517 struct skb_data *entry = (struct skb_data *)skb->cb;
1518
1519 usb_free_urb(entry->urb);
1520 dev_kfree_skb(skb);
1521 }
1522
1523 /*-------------------------------------------------------------------------*/
1524
1525 // tasklet (work deferred from completions, in_irq) or timer
1526
usbnet_bh(struct timer_list * t)1527 static void usbnet_bh (struct timer_list *t)
1528 {
1529 struct usbnet *dev = from_timer(dev, t, delay);
1530 struct sk_buff *skb;
1531 struct skb_data *entry;
1532
1533 while ((skb = skb_dequeue (&dev->done))) {
1534 entry = (struct skb_data *) skb->cb;
1535 switch (entry->state) {
1536 case rx_done:
1537 if (rx_process(dev, skb))
1538 usb_free_skb(skb);
1539 continue;
1540 case tx_done:
1541 kfree(entry->urb->sg);
1542 fallthrough;
1543 case rx_cleanup:
1544 usb_free_skb(skb);
1545 continue;
1546 default:
1547 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1548 }
1549 }
1550
1551 /* restart RX again after disabling due to high error rate */
1552 clear_bit(EVENT_RX_KILL, &dev->flags);
1553
1554 /* waiting for all pending urbs to complete?
1555 * only then can we forgo submitting anew
1556 */
1557 if (waitqueue_active(&dev->wait)) {
1558 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1559 wake_up_all(&dev->wait);
1560
1561 // or are we maybe short a few urbs?
1562 } else if (netif_running (dev->net) &&
1563 netif_device_present (dev->net) &&
1564 netif_carrier_ok(dev->net) &&
1565 !timer_pending(&dev->delay) &&
1566 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1567 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1568 int temp = dev->rxq.qlen;
1569
1570 if (temp < RX_QLEN(dev)) {
1571 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1572 return;
1573 if (temp != dev->rxq.qlen)
1574 netif_dbg(dev, link, dev->net,
1575 "rxqlen %d --> %d\n",
1576 temp, dev->rxq.qlen);
1577 if (dev->rxq.qlen < RX_QLEN(dev))
1578 tasklet_schedule (&dev->bh);
1579 }
1580 if (dev->txq.qlen < TX_QLEN (dev))
1581 netif_wake_queue (dev->net);
1582 }
1583 }
1584
usbnet_bh_tasklet(struct tasklet_struct * t)1585 static void usbnet_bh_tasklet(struct tasklet_struct *t)
1586 {
1587 struct usbnet *dev = from_tasklet(dev, t, bh);
1588
1589 usbnet_bh(&dev->delay);
1590 }
1591
1592
1593 /*-------------------------------------------------------------------------
1594 *
1595 * USB Device Driver support
1596 *
1597 *-------------------------------------------------------------------------*/
1598
1599 // precondition: never called in_interrupt
1600
usbnet_disconnect(struct usb_interface * intf)1601 void usbnet_disconnect (struct usb_interface *intf)
1602 {
1603 struct usbnet *dev;
1604 struct usb_device *xdev;
1605 struct net_device *net;
1606 struct urb *urb;
1607
1608 dev = usb_get_intfdata(intf);
1609 usb_set_intfdata(intf, NULL);
1610 if (!dev)
1611 return;
1612
1613 xdev = interface_to_usbdev (intf);
1614
1615 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1616 intf->dev.driver->name,
1617 xdev->bus->bus_name, xdev->devpath,
1618 dev->driver_info->description);
1619
1620 net = dev->net;
1621 unregister_netdev (net);
1622
1623 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1624 dev_kfree_skb(urb->context);
1625 kfree(urb->sg);
1626 usb_free_urb(urb);
1627 }
1628
1629 if (dev->driver_info->unbind)
1630 dev->driver_info->unbind(dev, intf);
1631
1632 usb_kill_urb(dev->interrupt);
1633 usb_free_urb(dev->interrupt);
1634 kfree(dev->padding_pkt);
1635
1636 free_percpu(net->tstats);
1637 free_netdev(net);
1638 }
1639 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1640
1641 static const struct net_device_ops usbnet_netdev_ops = {
1642 .ndo_open = usbnet_open,
1643 .ndo_stop = usbnet_stop,
1644 .ndo_start_xmit = usbnet_start_xmit,
1645 .ndo_tx_timeout = usbnet_tx_timeout,
1646 .ndo_set_rx_mode = usbnet_set_rx_mode,
1647 .ndo_change_mtu = usbnet_change_mtu,
1648 .ndo_get_stats64 = dev_get_tstats64,
1649 .ndo_set_mac_address = eth_mac_addr,
1650 .ndo_validate_addr = eth_validate_addr,
1651 };
1652
1653 /*-------------------------------------------------------------------------*/
1654
1655 // precondition: never called in_interrupt
1656
1657 static struct device_type wlan_type = {
1658 .name = "wlan",
1659 };
1660
1661 static struct device_type wwan_type = {
1662 .name = "wwan",
1663 };
1664
1665 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1666 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1667 {
1668 struct usbnet *dev;
1669 struct net_device *net;
1670 struct usb_host_interface *interface;
1671 const struct driver_info *info;
1672 struct usb_device *xdev;
1673 int status;
1674 const char *name;
1675 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1676
1677 /* usbnet already took usb runtime pm, so have to enable the feature
1678 * for usb interface, otherwise usb_autopm_get_interface may return
1679 * failure if RUNTIME_PM is enabled.
1680 */
1681 if (!driver->supports_autosuspend) {
1682 driver->supports_autosuspend = 1;
1683 pm_runtime_enable(&udev->dev);
1684 }
1685
1686 name = udev->dev.driver->name;
1687 info = (const struct driver_info *) prod->driver_info;
1688 if (!info) {
1689 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1690 return -ENODEV;
1691 }
1692 xdev = interface_to_usbdev (udev);
1693 interface = udev->cur_altsetting;
1694
1695 status = -ENOMEM;
1696
1697 // set up our own records
1698 net = alloc_etherdev(sizeof(*dev));
1699 if (!net)
1700 goto out;
1701
1702 /* netdev_printk() needs this so do it as early as possible */
1703 SET_NETDEV_DEV(net, &udev->dev);
1704
1705 dev = netdev_priv(net);
1706 dev->udev = xdev;
1707 dev->intf = udev;
1708 dev->driver_info = info;
1709 dev->driver_name = name;
1710 dev->rx_speed = SPEED_UNSET;
1711 dev->tx_speed = SPEED_UNSET;
1712
1713 net->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1714 if (!net->tstats)
1715 goto out0;
1716
1717 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1718 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1719 init_waitqueue_head(&dev->wait);
1720 skb_queue_head_init (&dev->rxq);
1721 skb_queue_head_init (&dev->txq);
1722 skb_queue_head_init (&dev->done);
1723 skb_queue_head_init(&dev->rxq_pause);
1724 tasklet_setup(&dev->bh, usbnet_bh_tasklet);
1725 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1726 init_usb_anchor(&dev->deferred);
1727 timer_setup(&dev->delay, usbnet_bh, 0);
1728 mutex_init (&dev->phy_mutex);
1729 mutex_init(&dev->interrupt_mutex);
1730 dev->interrupt_count = 0;
1731
1732 dev->net = net;
1733 strscpy(net->name, "usb%d", sizeof(net->name));
1734 eth_hw_addr_set(net, node_id);
1735
1736 /* rx and tx sides can use different message sizes;
1737 * bind() should set rx_urb_size in that case.
1738 */
1739 dev->hard_mtu = net->mtu + net->hard_header_len;
1740 net->min_mtu = 0;
1741 net->max_mtu = ETH_MAX_MTU;
1742
1743 net->netdev_ops = &usbnet_netdev_ops;
1744 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1745 net->ethtool_ops = &usbnet_ethtool_ops;
1746
1747 // allow device-specific bind/init procedures
1748 // NOTE net->name still not usable ...
1749 if (info->bind) {
1750 status = info->bind (dev, udev);
1751 if (status < 0)
1752 goto out1;
1753
1754 // heuristic: "usb%d" for links we know are two-host,
1755 // else "eth%d" when there's reasonable doubt. userspace
1756 // can rename the link if it knows better.
1757 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1758 ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1759 (net->dev_addr [0] & 0x02) == 0))
1760 strscpy(net->name, "eth%d", sizeof(net->name));
1761 /* WLAN devices should always be named "wlan%d" */
1762 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1763 strscpy(net->name, "wlan%d", sizeof(net->name));
1764 /* WWAN devices should always be named "wwan%d" */
1765 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1766 strscpy(net->name, "wwan%d", sizeof(net->name));
1767
1768 /* devices that cannot do ARP */
1769 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1770 net->flags |= IFF_NOARP;
1771
1772 /* maybe the remote can't receive an Ethernet MTU */
1773 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1774 net->mtu = dev->hard_mtu - net->hard_header_len;
1775 } else if (!info->in || !info->out)
1776 status = usbnet_get_endpoints (dev, udev);
1777 else {
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 }
1788 if (status >= 0 && dev->status)
1789 status = init_status (dev, udev);
1790 if (status < 0)
1791 goto out3;
1792
1793 if (!dev->rx_urb_size)
1794 dev->rx_urb_size = dev->hard_mtu;
1795 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1796 if (dev->maxpacket == 0) {
1797 /* that is a broken device */
1798 status = -ENODEV;
1799 goto out4;
1800 }
1801
1802 /* let userspace know we have a random address */
1803 if (ether_addr_equal(net->dev_addr, node_id))
1804 net->addr_assign_type = NET_ADDR_RANDOM;
1805
1806 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1807 SET_NETDEV_DEVTYPE(net, &wlan_type);
1808 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1809 SET_NETDEV_DEVTYPE(net, &wwan_type);
1810
1811 /* initialize max rx_qlen and tx_qlen */
1812 usbnet_update_max_qlen(dev);
1813
1814 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1815 !(info->flags & FLAG_MULTI_PACKET)) {
1816 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1817 if (!dev->padding_pkt) {
1818 status = -ENOMEM;
1819 goto out4;
1820 }
1821 }
1822
1823 status = register_netdev (net);
1824 if (status)
1825 goto out5;
1826 netif_info(dev, probe, dev->net,
1827 "register '%s' at usb-%s-%s, %s, %pM\n",
1828 udev->dev.driver->name,
1829 xdev->bus->bus_name, xdev->devpath,
1830 dev->driver_info->description,
1831 net->dev_addr);
1832
1833 // ok, it's ready to go.
1834 usb_set_intfdata (udev, dev);
1835
1836 netif_device_attach (net);
1837
1838 if (dev->driver_info->flags & FLAG_LINK_INTR)
1839 usbnet_link_change(dev, 0, 0);
1840
1841 return 0;
1842
1843 out5:
1844 kfree(dev->padding_pkt);
1845 out4:
1846 usb_free_urb(dev->interrupt);
1847 out3:
1848 if (info->unbind)
1849 info->unbind (dev, udev);
1850 out1:
1851 /* subdrivers must undo all they did in bind() if they
1852 * fail it, but we may fail later and a deferred kevent
1853 * may trigger an error resubmitting itself and, worse,
1854 * schedule a timer. So we kill it all just in case.
1855 */
1856 cancel_work_sync(&dev->kevent);
1857 del_timer_sync(&dev->delay);
1858 free_percpu(net->tstats);
1859 out0:
1860 free_netdev(net);
1861 out:
1862 return status;
1863 }
1864 EXPORT_SYMBOL_GPL(usbnet_probe);
1865
1866 /*-------------------------------------------------------------------------*/
1867
1868 /*
1869 * suspend the whole driver as soon as the first interface is suspended
1870 * resume only when the last interface is resumed
1871 */
1872
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1873 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1874 {
1875 struct usbnet *dev = usb_get_intfdata(intf);
1876
1877 if (!dev->suspend_count++) {
1878 spin_lock_irq(&dev->txq.lock);
1879 /* don't autosuspend while transmitting */
1880 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1881 dev->suspend_count--;
1882 spin_unlock_irq(&dev->txq.lock);
1883 return -EBUSY;
1884 } else {
1885 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1886 spin_unlock_irq(&dev->txq.lock);
1887 }
1888 /*
1889 * accelerate emptying of the rx and queues, to avoid
1890 * having everything error out.
1891 */
1892 netif_device_detach (dev->net);
1893 usbnet_terminate_urbs(dev);
1894 __usbnet_status_stop_force(dev);
1895
1896 /*
1897 * reattach so runtime management can use and
1898 * wake the device
1899 */
1900 netif_device_attach (dev->net);
1901 }
1902 return 0;
1903 }
1904 EXPORT_SYMBOL_GPL(usbnet_suspend);
1905
usbnet_resume(struct usb_interface * intf)1906 int usbnet_resume (struct usb_interface *intf)
1907 {
1908 struct usbnet *dev = usb_get_intfdata(intf);
1909 struct sk_buff *skb;
1910 struct urb *res;
1911 int retval;
1912
1913 if (!--dev->suspend_count) {
1914 /* resume interrupt URB if it was previously submitted */
1915 __usbnet_status_start_force(dev, GFP_NOIO);
1916
1917 spin_lock_irq(&dev->txq.lock);
1918 while ((res = usb_get_from_anchor(&dev->deferred))) {
1919
1920 skb = (struct sk_buff *)res->context;
1921 retval = usb_submit_urb(res, GFP_ATOMIC);
1922 if (retval < 0) {
1923 dev_kfree_skb_any(skb);
1924 kfree(res->sg);
1925 usb_free_urb(res);
1926 usb_autopm_put_interface_async(dev->intf);
1927 } else {
1928 netif_trans_update(dev->net);
1929 __skb_queue_tail(&dev->txq, skb);
1930 }
1931 }
1932
1933 smp_mb();
1934 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1935 spin_unlock_irq(&dev->txq.lock);
1936
1937 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1938 /* handle remote wakeup ASAP
1939 * we cannot race against stop
1940 */
1941 if (netif_device_present(dev->net) &&
1942 !timer_pending(&dev->delay) &&
1943 !test_bit(EVENT_RX_HALT, &dev->flags))
1944 rx_alloc_submit(dev, GFP_NOIO);
1945
1946 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1947 netif_tx_wake_all_queues(dev->net);
1948 tasklet_schedule (&dev->bh);
1949 }
1950 }
1951
1952 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1953 usb_autopm_get_interface_no_resume(intf);
1954
1955 return 0;
1956 }
1957 EXPORT_SYMBOL_GPL(usbnet_resume);
1958
1959 /*
1960 * Either a subdriver implements manage_power, then it is assumed to always
1961 * be ready to be suspended or it reports the readiness to be suspended
1962 * explicitly
1963 */
usbnet_device_suggests_idle(struct usbnet * dev)1964 void usbnet_device_suggests_idle(struct usbnet *dev)
1965 {
1966 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1967 dev->intf->needs_remote_wakeup = 1;
1968 usb_autopm_put_interface_async(dev->intf);
1969 }
1970 }
1971 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1972
1973 /*
1974 * For devices that can do without special commands
1975 */
usbnet_manage_power(struct usbnet * dev,int on)1976 int usbnet_manage_power(struct usbnet *dev, int on)
1977 {
1978 dev->intf->needs_remote_wakeup = on;
1979 return 0;
1980 }
1981 EXPORT_SYMBOL(usbnet_manage_power);
1982
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)1983 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1984 {
1985 /* update link after link is reseted */
1986 if (link && !need_reset)
1987 netif_carrier_on(dev->net);
1988 else
1989 netif_carrier_off(dev->net);
1990
1991 if (need_reset && link)
1992 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1993 else
1994 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1995 }
1996 EXPORT_SYMBOL(usbnet_link_change);
1997
1998 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)1999 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2000 u16 value, u16 index, void *data, u16 size)
2001 {
2002 void *buf = NULL;
2003 int err = -ENOMEM;
2004
2005 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2006 " value=0x%04x index=0x%04x size=%d\n",
2007 cmd, reqtype, value, index, size);
2008
2009 if (size) {
2010 buf = kmalloc(size, GFP_NOIO);
2011 if (!buf)
2012 goto out;
2013 }
2014
2015 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2016 cmd, reqtype, value, index, buf, size,
2017 USB_CTRL_GET_TIMEOUT);
2018 if (err > 0 && err <= size) {
2019 if (data)
2020 memcpy(data, buf, err);
2021 else
2022 netdev_dbg(dev->net,
2023 "Huh? Data requested but thrown away.\n");
2024 }
2025 kfree(buf);
2026 out:
2027 return err;
2028 }
2029
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2030 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2031 u16 value, u16 index, const void *data,
2032 u16 size)
2033 {
2034 void *buf = NULL;
2035 int err = -ENOMEM;
2036
2037 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2038 " value=0x%04x index=0x%04x size=%d\n",
2039 cmd, reqtype, value, index, size);
2040
2041 if (data) {
2042 buf = kmemdup(data, size, GFP_NOIO);
2043 if (!buf)
2044 goto out;
2045 } else {
2046 if (size) {
2047 WARN_ON_ONCE(1);
2048 err = -EINVAL;
2049 goto out;
2050 }
2051 }
2052
2053 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2054 cmd, reqtype, value, index, buf, size,
2055 USB_CTRL_SET_TIMEOUT);
2056 kfree(buf);
2057
2058 out:
2059 return err;
2060 }
2061
2062 /*
2063 * The function can't be called inside suspend/resume callback,
2064 * otherwise deadlock will be caused.
2065 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2066 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2067 u16 value, u16 index, void *data, u16 size)
2068 {
2069 int ret;
2070
2071 if (usb_autopm_get_interface(dev->intf) < 0)
2072 return -ENODEV;
2073 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2074 data, size);
2075 usb_autopm_put_interface(dev->intf);
2076 return ret;
2077 }
2078 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2079
2080 /*
2081 * The function can't be called inside suspend/resume callback,
2082 * otherwise deadlock will be caused.
2083 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2084 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2085 u16 value, u16 index, const void *data, u16 size)
2086 {
2087 int ret;
2088
2089 if (usb_autopm_get_interface(dev->intf) < 0)
2090 return -ENODEV;
2091 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2092 data, size);
2093 usb_autopm_put_interface(dev->intf);
2094 return ret;
2095 }
2096 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2097
2098 /*
2099 * The function can be called inside suspend/resume callback safely
2100 * and should only be called by suspend/resume callback generally.
2101 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2102 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2103 u16 value, u16 index, void *data, u16 size)
2104 {
2105 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2106 data, size);
2107 }
2108 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2109
2110 /*
2111 * The function can be called inside suspend/resume callback safely
2112 * and should only be called by suspend/resume callback generally.
2113 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2114 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2115 u16 value, u16 index, const void *data,
2116 u16 size)
2117 {
2118 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2119 data, size);
2120 }
2121 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2122
usbnet_async_cmd_cb(struct urb * urb)2123 static void usbnet_async_cmd_cb(struct urb *urb)
2124 {
2125 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2126 int status = urb->status;
2127
2128 if (status < 0)
2129 dev_dbg(&urb->dev->dev, "%s failed with %d",
2130 __func__, status);
2131
2132 kfree(req);
2133 usb_free_urb(urb);
2134 }
2135
2136 /*
2137 * The caller must make sure that device can't be put into suspend
2138 * state until the control URB completes.
2139 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2140 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2141 u16 value, u16 index, const void *data, u16 size)
2142 {
2143 struct usb_ctrlrequest *req;
2144 struct urb *urb;
2145 int err = -ENOMEM;
2146 void *buf = NULL;
2147
2148 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2149 " value=0x%04x index=0x%04x size=%d\n",
2150 cmd, reqtype, value, index, size);
2151
2152 urb = usb_alloc_urb(0, GFP_ATOMIC);
2153 if (!urb)
2154 goto fail;
2155
2156 if (data) {
2157 buf = kmemdup(data, size, GFP_ATOMIC);
2158 if (!buf) {
2159 netdev_err(dev->net, "Error allocating buffer"
2160 " in %s!\n", __func__);
2161 goto fail_free_urb;
2162 }
2163 }
2164
2165 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2166 if (!req)
2167 goto fail_free_buf;
2168
2169 req->bRequestType = reqtype;
2170 req->bRequest = cmd;
2171 req->wValue = cpu_to_le16(value);
2172 req->wIndex = cpu_to_le16(index);
2173 req->wLength = cpu_to_le16(size);
2174
2175 usb_fill_control_urb(urb, dev->udev,
2176 usb_sndctrlpipe(dev->udev, 0),
2177 (void *)req, buf, size,
2178 usbnet_async_cmd_cb, req);
2179 urb->transfer_flags |= URB_FREE_BUFFER;
2180
2181 err = usb_submit_urb(urb, GFP_ATOMIC);
2182 if (err < 0) {
2183 netdev_err(dev->net, "Error submitting the control"
2184 " message: status=%d\n", err);
2185 goto fail_free_all;
2186 }
2187 return 0;
2188
2189 fail_free_all:
2190 kfree(req);
2191 fail_free_buf:
2192 kfree(buf);
2193 /*
2194 * avoid a double free
2195 * needed because the flag can be set only
2196 * after filling the URB
2197 */
2198 urb->transfer_flags = 0;
2199 fail_free_urb:
2200 usb_free_urb(urb);
2201 fail:
2202 return err;
2203
2204 }
2205 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2206 /*-------------------------------------------------------------------------*/
2207
usbnet_init(void)2208 static int __init usbnet_init(void)
2209 {
2210 /* Compiler should optimize this out. */
2211 BUILD_BUG_ON(
2212 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2213
2214 eth_random_addr(node_id);
2215 return 0;
2216 }
2217 module_init(usbnet_init);
2218
usbnet_exit(void)2219 static void __exit usbnet_exit(void)
2220 {
2221 }
2222 module_exit(usbnet_exit);
2223
2224 MODULE_AUTHOR("David Brownell");
2225 MODULE_DESCRIPTION("USB network driver framework");
2226 MODULE_LICENSE("GPL");
2227