1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * USB Network driver infrastructure
4 * Copyright (C) 2000-2005 by David Brownell
5 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
6 */
7
8 /*
9 * This is a generic "USB networking" framework that works with several
10 * kinds of full and high speed networking devices: host-to-host cables,
11 * smart usb peripherals, and actual Ethernet adapters.
12 *
13 * These devices usually differ in terms of control protocols (if they
14 * even have one!) and sometimes they define new framing to wrap or batch
15 * Ethernet packets. Otherwise, they talk to USB pretty much the same,
16 * so interface (un)binding, endpoint I/O queues, fault handling, and other
17 * issues can usefully be addressed by this framework.
18 */
19
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/ctype.h>
25 #include <linux/ethtool.h>
26 #include <linux/workqueue.h>
27 #include <linux/mii.h>
28 #include <linux/usb.h>
29 #include <linux/usb/usbnet.h>
30 #include <linux/slab.h>
31 #include <linux/kernel.h>
32 #include <linux/pm_runtime.h>
33
34 /*-------------------------------------------------------------------------*/
35
36 /*
37 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
38 * Several dozen bytes of IPv4 data can fit in two such transactions.
39 * One maximum size Ethernet packet takes twenty four of them.
40 * For high speed, each frame comfortably fits almost 36 max size
41 * Ethernet packets (so queues should be bigger).
42 *
43 * The goal is to let the USB host controller be busy for 5msec or
44 * more before an irq is required, under load. Jumbograms change
45 * the equation.
46 */
47 #define MAX_QUEUE_MEMORY (60 * 1518)
48 #define RX_QLEN(dev) ((dev)->rx_qlen)
49 #define TX_QLEN(dev) ((dev)->tx_qlen)
50
51 // reawaken network queue this soon after stopping; else watchdog barks
52 #define TX_TIMEOUT_JIFFIES (5*HZ)
53
54 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
55 * us (it polls at HZ/4 usually) before we report too many false errors.
56 */
57 #define THROTTLE_JIFFIES (HZ/8)
58
59 // between wakeups
60 #define UNLINK_TIMEOUT_MS 3
61
62 /*-------------------------------------------------------------------------*/
63
64 /* use ethtool to change the level for any given device */
65 static int msg_level = -1;
66 module_param (msg_level, int, 0);
67 MODULE_PARM_DESC (msg_level, "Override default message level");
68
69 /*-------------------------------------------------------------------------*/
70
71 static const char * const usbnet_event_names[] = {
72 [EVENT_TX_HALT] = "EVENT_TX_HALT",
73 [EVENT_RX_HALT] = "EVENT_RX_HALT",
74 [EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
75 [EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
76 [EVENT_LINK_RESET] = "EVENT_LINK_RESET",
77 [EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
78 [EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
79 [EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
80 [EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
81 [EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
82 [EVENT_RX_KILL] = "EVENT_RX_KILL",
83 [EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
84 [EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
85 [EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
86 };
87
88 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)89 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
90 {
91 int tmp;
92 struct usb_host_interface *alt = NULL;
93 struct usb_host_endpoint *in = NULL, *out = NULL;
94 struct usb_host_endpoint *status = NULL;
95
96 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
97 unsigned ep;
98
99 in = out = status = NULL;
100 alt = intf->altsetting + tmp;
101
102 /* take the first altsetting with in-bulk + out-bulk;
103 * remember any status endpoint, just in case;
104 * ignore other endpoints and altsettings.
105 */
106 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
107 struct usb_host_endpoint *e;
108 int intr = 0;
109
110 e = alt->endpoint + ep;
111
112 /* ignore endpoints which cannot transfer data */
113 if (!usb_endpoint_maxp(&e->desc))
114 continue;
115
116 switch (e->desc.bmAttributes) {
117 case USB_ENDPOINT_XFER_INT:
118 if (!usb_endpoint_dir_in(&e->desc))
119 continue;
120 intr = 1;
121 fallthrough;
122 case USB_ENDPOINT_XFER_BULK:
123 break;
124 default:
125 continue;
126 }
127 if (usb_endpoint_dir_in(&e->desc)) {
128 if (!intr && !in)
129 in = e;
130 else if (intr && !status)
131 status = e;
132 } else {
133 if (!out)
134 out = e;
135 }
136 }
137 if (in && out)
138 break;
139 }
140 if (!alt || !in || !out)
141 return -EINVAL;
142
143 if (alt->desc.bAlternateSetting != 0 ||
144 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
145 tmp = usb_set_interface(dev->udev, alt->desc.bInterfaceNumber,
146 alt->desc.bAlternateSetting);
147 if (tmp < 0)
148 return tmp;
149 }
150
151 dev->in = usb_rcvbulkpipe(dev->udev,
152 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
153 dev->out = usb_sndbulkpipe(dev->udev,
154 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
155 dev->status = status;
156 return 0;
157 }
158 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
159
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)160 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
161 {
162 u8 addr[ETH_ALEN];
163 int tmp = -1, ret;
164 unsigned char buf [13];
165
166 ret = usb_string(dev->udev, iMACAddress, buf, sizeof(buf));
167 if (ret == 12)
168 tmp = hex2bin(addr, buf, 6);
169 if (tmp < 0) {
170 dev_dbg(&dev->udev->dev,
171 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
172 if (ret >= 0)
173 ret = -EINVAL;
174 return ret;
175 }
176 eth_hw_addr_set(dev->net, addr);
177 return 0;
178 }
179 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
180
usbnet_needs_usb_name_format(struct usbnet * dev,struct net_device * net)181 static bool usbnet_needs_usb_name_format(struct usbnet *dev, struct net_device *net)
182 {
183 /* Point to point devices which don't have a real MAC address
184 * (or report a fake local one) have historically used the usb%d
185 * naming. Preserve this..
186 */
187 return (dev->driver_info->flags & FLAG_POINTTOPOINT) != 0 &&
188 (is_zero_ether_addr(net->dev_addr) ||
189 is_local_ether_addr(net->dev_addr));
190 }
191
intr_complete(struct urb * urb)192 static void intr_complete(struct urb *urb)
193 {
194 struct usbnet *dev = urb->context;
195 int status = urb->status;
196
197 switch (status) {
198 /* success */
199 case 0:
200 dev->driver_info->status(dev, urb);
201 break;
202
203 /* software-driven interface shutdown */
204 case -ENOENT: /* urb killed */
205 case -ESHUTDOWN: /* hardware gone */
206 netif_dbg(dev, ifdown, dev->net,
207 "intr shutdown, code %d\n", status);
208 return;
209
210 /* NOTE: not throttling like RX/TX, since this endpoint
211 * already polls infrequently
212 */
213 default:
214 netdev_dbg(dev->net, "intr status %d\n", status);
215 break;
216 }
217
218 status = usb_submit_urb(urb, GFP_ATOMIC);
219 if (status != 0)
220 netif_err(dev, timer, dev->net,
221 "intr resubmit --> %d\n", status);
222 }
223
init_status(struct usbnet * dev,struct usb_interface * intf)224 static int init_status(struct usbnet *dev, struct usb_interface *intf)
225 {
226 char *buf = NULL;
227 unsigned pipe = 0;
228 unsigned maxp;
229 unsigned period;
230
231 if (!dev->driver_info->status)
232 return 0;
233
234 pipe = usb_rcvintpipe(dev->udev,
235 dev->status->desc.bEndpointAddress
236 & USB_ENDPOINT_NUMBER_MASK);
237 maxp = usb_maxpacket(dev->udev, pipe);
238
239 /* avoid 1 msec chatter: min 8 msec poll rate */
240 period = max ((int) dev->status->desc.bInterval,
241 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
242
243 buf = kmalloc(maxp, GFP_KERNEL);
244 if (buf) {
245 dev->interrupt = usb_alloc_urb(0, GFP_KERNEL);
246 if (!dev->interrupt) {
247 kfree(buf);
248 return -ENOMEM;
249 } else {
250 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
251 buf, maxp, intr_complete, dev, period);
252 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
253 dev_dbg(&intf->dev,
254 "status ep%din, %d bytes period %d\n",
255 usb_pipeendpoint(pipe), maxp, period);
256 }
257 }
258 return 0;
259 }
260
261 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)262 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
263 {
264 int ret = 0;
265
266 WARN_ON_ONCE(dev->interrupt == NULL);
267 if (dev->interrupt) {
268 mutex_lock(&dev->interrupt_mutex);
269
270 if (++dev->interrupt_count == 1)
271 ret = usb_submit_urb(dev->interrupt, mem_flags);
272
273 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
274 dev->interrupt_count);
275 mutex_unlock(&dev->interrupt_mutex);
276 }
277 return ret;
278 }
279 EXPORT_SYMBOL_GPL(usbnet_status_start);
280
281 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)282 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
283 {
284 int ret = 0;
285
286 mutex_lock(&dev->interrupt_mutex);
287 if (dev->interrupt_count) {
288 ret = usb_submit_urb(dev->interrupt, mem_flags);
289 dev_dbg(&dev->udev->dev,
290 "submitted interrupt URB for resume\n");
291 }
292 mutex_unlock(&dev->interrupt_mutex);
293 return ret;
294 }
295
296 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)297 void usbnet_status_stop(struct usbnet *dev)
298 {
299 if (dev->interrupt) {
300 mutex_lock(&dev->interrupt_mutex);
301 WARN_ON(dev->interrupt_count == 0);
302
303 if (dev->interrupt_count && --dev->interrupt_count == 0)
304 usb_kill_urb(dev->interrupt);
305
306 dev_dbg(&dev->udev->dev,
307 "decremented interrupt URB count to %d\n",
308 dev->interrupt_count);
309 mutex_unlock(&dev->interrupt_mutex);
310 }
311 }
312 EXPORT_SYMBOL_GPL(usbnet_status_stop);
313
314 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)315 static void __usbnet_status_stop_force(struct usbnet *dev)
316 {
317 if (dev->interrupt) {
318 mutex_lock(&dev->interrupt_mutex);
319 usb_kill_urb(dev->interrupt);
320 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
321 mutex_unlock(&dev->interrupt_mutex);
322 }
323 }
324
325 /* Passes this packet up the stack, updating its accounting.
326 * Some link protocols batch packets, so their rx_fixup paths
327 * can return clones as well as just modify the original skb.
328 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)329 void usbnet_skb_return(struct usbnet *dev, struct sk_buff *skb)
330 {
331 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
332 unsigned long flags;
333 int status;
334
335 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
336 skb_queue_tail(&dev->rxq_pause, skb);
337 return;
338 }
339
340 /* only update if unset to allow minidriver rx_fixup override */
341 if (skb->protocol == 0)
342 skb->protocol = eth_type_trans(skb, dev->net);
343
344 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
345 u64_stats_inc(&stats64->rx_packets);
346 u64_stats_add(&stats64->rx_bytes, skb->len);
347 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
348
349 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
350 skb->len + sizeof(struct ethhdr), skb->protocol);
351 memset(skb->cb, 0, sizeof(struct skb_data));
352
353 if (skb_defer_rx_timestamp(skb))
354 return;
355
356 status = netif_rx (skb);
357 if (status != NET_RX_SUCCESS)
358 netif_dbg(dev, rx_err, dev->net,
359 "netif_rx status %d\n", status);
360 }
361 EXPORT_SYMBOL_GPL(usbnet_skb_return);
362
363 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)364 void usbnet_update_max_qlen(struct usbnet *dev)
365 {
366 enum usb_device_speed speed = dev->udev->speed;
367
368 if (!dev->rx_urb_size || !dev->hard_mtu)
369 goto insanity;
370 switch (speed) {
371 case USB_SPEED_HIGH:
372 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
373 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
374 break;
375 case USB_SPEED_SUPER:
376 case USB_SPEED_SUPER_PLUS:
377 /*
378 * Not take default 5ms qlen for super speed HC to
379 * save memory, and iperf tests show 2.5ms qlen can
380 * work well
381 */
382 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
383 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
384 break;
385 default:
386 insanity:
387 dev->rx_qlen = dev->tx_qlen = 4;
388 }
389 }
390 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
391
392
393 /*-------------------------------------------------------------------------
394 *
395 * Network Device Driver (peer link to "Host Device", from USB host)
396 *
397 *-------------------------------------------------------------------------*/
398
usbnet_change_mtu(struct net_device * net,int new_mtu)399 int usbnet_change_mtu(struct net_device *net, int new_mtu)
400 {
401 struct usbnet *dev = netdev_priv(net);
402 int ll_mtu = new_mtu + net->hard_header_len;
403 int old_hard_mtu = dev->hard_mtu;
404 int old_rx_urb_size = dev->rx_urb_size;
405
406 // no second zero-length packet read wanted after mtu-sized packets
407 if ((ll_mtu % dev->maxpacket) == 0)
408 return -EDOM;
409 WRITE_ONCE(net->mtu, new_mtu);
410
411 dev->hard_mtu = net->mtu + net->hard_header_len;
412 if (dev->rx_urb_size == old_hard_mtu) {
413 dev->rx_urb_size = dev->hard_mtu;
414 if (dev->rx_urb_size > old_rx_urb_size) {
415 usbnet_pause_rx(dev);
416 usbnet_unlink_rx_urbs(dev);
417 usbnet_resume_rx(dev);
418 }
419 }
420
421 /* max qlen depend on hard_mtu and rx_urb_size */
422 usbnet_update_max_qlen(dev);
423
424 return 0;
425 }
426 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
427
428 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)429 static void __usbnet_queue_skb(struct sk_buff_head *list,
430 struct sk_buff *newsk, enum skb_state state)
431 {
432 struct skb_data *entry = (struct skb_data *) newsk->cb;
433
434 __skb_queue_tail(list, newsk);
435 entry->state = state;
436 }
437
438 /*-------------------------------------------------------------------------*/
439
440 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
441 * completion callbacks. 2.5 should have fixed those bugs...
442 */
443
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)444 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
445 struct sk_buff_head *list, enum skb_state state)
446 {
447 unsigned long flags;
448 enum skb_state old_state;
449 struct skb_data *entry = (struct skb_data *) skb->cb;
450
451 spin_lock_irqsave(&list->lock, flags);
452 old_state = entry->state;
453 entry->state = state;
454 __skb_unlink(skb, list);
455
456 /* defer_bh() is never called with list == &dev->done.
457 * spin_lock_nested() tells lockdep that it is OK to take
458 * dev->done.lock here with list->lock held.
459 */
460 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
461
462 __skb_queue_tail(&dev->done, skb);
463 if (dev->done.qlen == 1)
464 queue_work(system_bh_wq, &dev->bh_work);
465 spin_unlock(&dev->done.lock);
466 spin_unlock_irqrestore(&list->lock, flags);
467 return old_state;
468 }
469
470 /* some work can't be done in tasklets, so we use keventd
471 *
472 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
473 * but tasklet_schedule() doesn't. hope the failure is rare.
474 */
usbnet_defer_kevent(struct usbnet * dev,int work)475 void usbnet_defer_kevent(struct usbnet *dev, int work)
476 {
477 set_bit (work, &dev->flags);
478 if (!usbnet_going_away(dev)) {
479 if (!schedule_work(&dev->kevent))
480 netdev_dbg(dev->net,
481 "kevent %s may have been dropped\n",
482 usbnet_event_names[work]);
483 else
484 netdev_dbg(dev->net,
485 "kevent %s scheduled\n", usbnet_event_names[work]);
486 }
487 }
488 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
489
490 /*-------------------------------------------------------------------------*/
491
492 static void rx_complete(struct urb *urb);
493
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)494 static int rx_submit(struct usbnet *dev, struct urb *urb, gfp_t flags)
495 {
496 struct sk_buff *skb;
497 struct skb_data *entry;
498 int retval = 0;
499 unsigned long lockflags;
500 size_t size = dev->rx_urb_size;
501
502 /* prevent rx skb allocation when error ratio is high */
503 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
504 usb_free_urb(urb);
505 return -ENOLINK;
506 }
507
508 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
509 skb = __netdev_alloc_skb(dev->net, size, flags);
510 else
511 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
512 if (!skb) {
513 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
514 usbnet_defer_kevent(dev, EVENT_RX_MEMORY);
515 usb_free_urb(urb);
516 return -ENOMEM;
517 }
518
519 entry = (struct skb_data *) skb->cb;
520 entry->urb = urb;
521 entry->dev = dev;
522 entry->length = 0;
523
524 usb_fill_bulk_urb(urb, dev->udev, dev->in,
525 skb->data, size, rx_complete, skb);
526
527 spin_lock_irqsave(&dev->rxq.lock, lockflags);
528
529 if (netif_running(dev->net) &&
530 netif_device_present(dev->net) &&
531 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
532 !test_bit(EVENT_RX_HALT, &dev->flags) &&
533 !test_bit(EVENT_DEV_ASLEEP, &dev->flags) &&
534 !usbnet_going_away(dev)) {
535 switch (retval = usb_submit_urb(urb, GFP_ATOMIC)) {
536 case -EPIPE:
537 usbnet_defer_kevent(dev, EVENT_RX_HALT);
538 break;
539 case -ENOMEM:
540 usbnet_defer_kevent(dev, EVENT_RX_MEMORY);
541 break;
542 case -ENODEV:
543 netif_dbg(dev, ifdown, dev->net, "device gone\n");
544 netif_device_detach(dev->net);
545 break;
546 case -EHOSTUNREACH:
547 retval = -ENOLINK;
548 break;
549 default:
550 netif_dbg(dev, rx_err, dev->net,
551 "rx submit, %d\n", retval);
552 queue_work(system_bh_wq, &dev->bh_work);
553 break;
554 case 0:
555 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
556 }
557 } else {
558 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
559 retval = -ENOLINK;
560 }
561 spin_unlock_irqrestore(&dev->rxq.lock, lockflags);
562 if (retval) {
563 dev_kfree_skb_any(skb);
564 usb_free_urb(urb);
565 }
566 return retval;
567 }
568
569
570 /*-------------------------------------------------------------------------*/
571
rx_process(struct usbnet * dev,struct sk_buff * skb)572 static inline int rx_process(struct usbnet *dev, struct sk_buff *skb)
573 {
574 if (dev->driver_info->rx_fixup &&
575 !dev->driver_info->rx_fixup(dev, skb)) {
576 /* With RX_ASSEMBLE, rx_fixup() must update counters */
577 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
578 dev->net->stats.rx_errors++;
579 return -EPROTO;
580 }
581 // else network stack removes extra byte if we forced a short packet
582
583 /* all data was already cloned from skb inside the driver */
584 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
585 return -EALREADY;
586
587 if (skb->len < ETH_HLEN) {
588 dev->net->stats.rx_errors++;
589 dev->net->stats.rx_length_errors++;
590 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
591 return -EPROTO;
592 }
593
594 usbnet_skb_return(dev, skb);
595 return 0;
596 }
597
598 /*-------------------------------------------------------------------------*/
599
rx_complete(struct urb * urb)600 static void rx_complete(struct urb *urb)
601 {
602 struct sk_buff *skb = (struct sk_buff *) urb->context;
603 struct skb_data *entry = (struct skb_data *) skb->cb;
604 struct usbnet *dev = entry->dev;
605 int urb_status = urb->status;
606 enum skb_state state;
607
608 skb_put(skb, urb->actual_length);
609 state = rx_done;
610 entry->urb = NULL;
611
612 switch (urb_status) {
613 /* success */
614 case 0:
615 break;
616
617 /* stalls need manual reset. this is rare ... except that
618 * when going through USB 2.0 TTs, unplug appears this way.
619 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
620 * storm, recovering as needed.
621 */
622 case -EPIPE:
623 dev->net->stats.rx_errors++;
624 usbnet_defer_kevent(dev, EVENT_RX_HALT);
625 fallthrough;
626
627 /* software-driven interface shutdown */
628 case -ECONNRESET: /* async unlink */
629 case -ESHUTDOWN: /* hardware gone */
630 netif_dbg(dev, ifdown, dev->net,
631 "rx shutdown, code %d\n", urb_status);
632 goto block;
633
634 /* we get controller i/o faults during hub_wq disconnect() delays.
635 * throttle down resubmits, to avoid log floods; just temporarily,
636 * so we still recover when the fault isn't a hub_wq delay.
637 */
638 case -EPROTO:
639 case -ETIME:
640 case -EILSEQ:
641 dev->net->stats.rx_errors++;
642 if (!timer_pending(&dev->delay)) {
643 mod_timer(&dev->delay, jiffies + THROTTLE_JIFFIES);
644 netif_dbg(dev, link, dev->net,
645 "rx throttle %d\n", urb_status);
646 }
647 block:
648 state = rx_cleanup;
649 entry->urb = urb;
650 urb = NULL;
651 break;
652
653 /* data overrun ... flush fifo? */
654 case -EOVERFLOW:
655 dev->net->stats.rx_over_errors++;
656 fallthrough;
657
658 default:
659 state = rx_cleanup;
660 dev->net->stats.rx_errors++;
661 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
662 break;
663 }
664
665 /* stop rx if packet error rate is high */
666 if (++dev->pkt_cnt > 30) {
667 dev->pkt_cnt = 0;
668 dev->pkt_err = 0;
669 } else {
670 if (state == rx_cleanup)
671 dev->pkt_err++;
672 if (dev->pkt_err > 20)
673 set_bit(EVENT_RX_KILL, &dev->flags);
674 }
675
676 state = defer_bh(dev, skb, &dev->rxq, state);
677
678 if (urb) {
679 if (netif_running(dev->net) &&
680 !test_bit(EVENT_RX_HALT, &dev->flags) &&
681 state != unlink_start) {
682 rx_submit(dev, urb, GFP_ATOMIC);
683 usb_mark_last_busy(dev->udev);
684 return;
685 }
686 usb_free_urb(urb);
687 }
688 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
689 }
690
691 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)692 void usbnet_pause_rx(struct usbnet *dev)
693 {
694 set_bit(EVENT_RX_PAUSED, &dev->flags);
695
696 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
697 }
698 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
699
usbnet_resume_rx(struct usbnet * dev)700 void usbnet_resume_rx(struct usbnet *dev)
701 {
702 struct sk_buff *skb;
703 int num = 0;
704
705 local_bh_disable();
706 clear_bit(EVENT_RX_PAUSED, &dev->flags);
707
708 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
709 usbnet_skb_return(dev, skb);
710 num++;
711 }
712
713 queue_work(system_bh_wq, &dev->bh_work);
714 local_bh_enable();
715
716 netif_dbg(dev, rx_status, dev->net,
717 "paused rx queue disabled, %d skbs requeued\n", num);
718 }
719 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
720
usbnet_purge_paused_rxq(struct usbnet * dev)721 void usbnet_purge_paused_rxq(struct usbnet *dev)
722 {
723 skb_queue_purge(&dev->rxq_pause);
724 }
725 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
726
727 /*-------------------------------------------------------------------------*/
728
729 // unlink pending rx/tx; completion handlers do all other cleanup
730
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)731 static int unlink_urbs(struct usbnet *dev, struct sk_buff_head *q)
732 {
733 unsigned long flags;
734 struct sk_buff *skb;
735 int count = 0;
736
737 spin_lock_irqsave (&q->lock, flags);
738 while (!skb_queue_empty(q)) {
739 struct skb_data *entry;
740 struct urb *urb;
741 int retval;
742
743 skb_queue_walk(q, skb) {
744 entry = (struct skb_data *) skb->cb;
745 if (entry->state != unlink_start)
746 goto found;
747 }
748 break;
749 found:
750 entry->state = unlink_start;
751 urb = entry->urb;
752
753 /*
754 * Get reference count of the URB to avoid it to be
755 * freed during usb_unlink_urb, which may trigger
756 * use-after-free problem inside usb_unlink_urb since
757 * usb_unlink_urb is always racing with .complete
758 * handler(include defer_bh).
759 */
760 usb_get_urb(urb);
761 spin_unlock_irqrestore(&q->lock, flags);
762 // during some PM-driven resume scenarios,
763 // these (async) unlinks complete immediately
764 retval = usb_unlink_urb(urb);
765 if (retval != -EINPROGRESS && retval != 0)
766 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
767 else
768 count++;
769 usb_put_urb(urb);
770 spin_lock_irqsave(&q->lock, flags);
771 }
772 spin_unlock_irqrestore(&q->lock, flags);
773 return count;
774 }
775
776 // Flush all pending rx urbs
777 // minidrivers may need to do this when the MTU changes
778
usbnet_unlink_rx_urbs(struct usbnet * dev)779 void usbnet_unlink_rx_urbs(struct usbnet *dev)
780 {
781 if (netif_running(dev->net)) {
782 (void) unlink_urbs (dev, &dev->rxq);
783 queue_work(system_bh_wq, &dev->bh_work);
784 }
785 }
786 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
787
788 /*-------------------------------------------------------------------------*/
789
wait_skb_queue_empty(struct sk_buff_head * q)790 static void wait_skb_queue_empty(struct sk_buff_head *q)
791 {
792 unsigned long flags;
793
794 spin_lock_irqsave(&q->lock, flags);
795 while (!skb_queue_empty(q)) {
796 spin_unlock_irqrestore(&q->lock, flags);
797 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
798 set_current_state(TASK_UNINTERRUPTIBLE);
799 spin_lock_irqsave(&q->lock, flags);
800 }
801 spin_unlock_irqrestore(&q->lock, flags);
802 }
803
804 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)805 static void usbnet_terminate_urbs(struct usbnet *dev)
806 {
807 DECLARE_WAITQUEUE(wait, current);
808 int temp;
809
810 /* ensure there are no more active urbs */
811 add_wait_queue(&dev->wait, &wait);
812 set_current_state(TASK_UNINTERRUPTIBLE);
813 temp = unlink_urbs(dev, &dev->txq) +
814 unlink_urbs(dev, &dev->rxq);
815
816 /* maybe wait for deletions to finish. */
817 wait_skb_queue_empty(&dev->rxq);
818 wait_skb_queue_empty(&dev->txq);
819 wait_skb_queue_empty(&dev->done);
820 netif_dbg(dev, ifdown, dev->net,
821 "waited for %d urb completions\n", temp);
822 set_current_state(TASK_RUNNING);
823 remove_wait_queue(&dev->wait, &wait);
824 }
825
usbnet_stop(struct net_device * net)826 int usbnet_stop(struct net_device *net)
827 {
828 struct usbnet *dev = netdev_priv(net);
829 const struct driver_info *info = dev->driver_info;
830 int retval, pm, mpn;
831
832 clear_bit(EVENT_DEV_OPEN, &dev->flags);
833 netif_stop_queue(net);
834
835 netif_info(dev, ifdown, dev->net,
836 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
837 net->stats.rx_packets, net->stats.tx_packets,
838 net->stats.rx_errors, net->stats.tx_errors);
839
840 /* to not race resume */
841 pm = usb_autopm_get_interface(dev->intf);
842 /* allow minidriver to stop correctly (wireless devices to turn off
843 * radio etc) */
844 if (info->stop) {
845 retval = info->stop(dev);
846 if (retval < 0)
847 netif_info(dev, ifdown, dev->net,
848 "stop fail (%d) usbnet usb-%s-%s, %s\n",
849 retval,
850 dev->udev->bus->bus_name, dev->udev->devpath,
851 info->description);
852 }
853
854 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
855 usbnet_terminate_urbs(dev);
856
857 usbnet_status_stop(dev);
858
859 usbnet_purge_paused_rxq(dev);
860
861 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
862
863 /* deferred work (timer, softirq, task) must also stop */
864 dev->flags = 0;
865 timer_delete_sync(&dev->delay);
866 cancel_work_sync(&dev->bh_work);
867 cancel_work_sync(&dev->kevent);
868
869 /* We have cyclic dependencies. Those calls are needed
870 * to break a cycle. We cannot fall into the gaps because
871 * we have a flag
872 */
873 cancel_work_sync(&dev->bh_work);
874 timer_delete_sync(&dev->delay);
875 cancel_work_sync(&dev->kevent);
876
877 netdev_reset_queue(net);
878
879 if (!pm)
880 usb_autopm_put_interface(dev->intf);
881
882 if (info->manage_power && mpn)
883 info->manage_power(dev, 0);
884 else
885 usb_autopm_put_interface(dev->intf);
886
887 return 0;
888 }
889 EXPORT_SYMBOL_GPL(usbnet_stop);
890
891 /*-------------------------------------------------------------------------*/
892
893 // posts reads, and enables write queuing
894
895 // precondition: never called in_interrupt
896
usbnet_open(struct net_device * net)897 int usbnet_open(struct net_device *net)
898 {
899 struct usbnet *dev = netdev_priv(net);
900 int retval;
901 const struct driver_info *info = dev->driver_info;
902
903 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
904 netif_info(dev, ifup, dev->net,
905 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
906 retval,
907 dev->udev->bus->bus_name,
908 dev->udev->devpath,
909 info->description);
910 goto done_nopm;
911 }
912
913 // put into "known safe" state
914 if (info->reset) {
915 retval = info->reset(dev);
916 if (retval < 0) {
917 netif_info(dev, ifup, dev->net,
918 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
919 retval,
920 dev->udev->bus->bus_name,
921 dev->udev->devpath,
922 info->description);
923 goto done;
924 }
925 }
926
927 /* hard_mtu or rx_urb_size may change in reset() */
928 usbnet_update_max_qlen(dev);
929
930 // insist peer be connected
931 if (info->check_connect) {
932 retval = info->check_connect(dev);
933 if (retval < 0) {
934 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
935 goto done;
936 }
937 }
938
939 /* start any status interrupt transfer */
940 if (dev->interrupt) {
941 retval = usbnet_status_start(dev, GFP_KERNEL);
942 if (retval < 0) {
943 netif_err(dev, ifup, dev->net,
944 "intr submit %d\n", retval);
945 goto done;
946 }
947 }
948
949 set_bit(EVENT_DEV_OPEN, &dev->flags);
950 netdev_reset_queue(net);
951 netif_start_queue (net);
952 netif_info(dev, ifup, dev->net,
953 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
954 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
955 dev->net->mtu,
956 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
957 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
958 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
959 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
960 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
961 "simple");
962
963 /* reset rx error state */
964 dev->pkt_cnt = 0;
965 dev->pkt_err = 0;
966 clear_bit(EVENT_RX_KILL, &dev->flags);
967
968 // delay posting reads until we're fully open
969 queue_work(system_bh_wq, &dev->bh_work);
970 if (info->manage_power) {
971 retval = info->manage_power(dev, 1);
972 if (retval < 0) {
973 retval = 0;
974 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
975 } else {
976 usb_autopm_put_interface(dev->intf);
977 }
978 }
979 return retval;
980 done:
981 usb_autopm_put_interface(dev->intf);
982 done_nopm:
983 return retval;
984 }
985 EXPORT_SYMBOL_GPL(usbnet_open);
986
987 /*-------------------------------------------------------------------------*/
988
989 /* ethtool methods; minidrivers may need to add some more, but
990 * they'll probably want to use this base set.
991 */
992
993 /* These methods are written on the assumption that the device
994 * uses MII
995 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)996 int usbnet_get_link_ksettings_mii(struct net_device *net,
997 struct ethtool_link_ksettings *cmd)
998 {
999 struct usbnet *dev = netdev_priv(net);
1000
1001 if (!dev->mii.mdio_read)
1002 return -EOPNOTSUPP;
1003
1004 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
1005
1006 return 0;
1007 }
1008 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
1009
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)1010 int usbnet_get_link_ksettings_internal(struct net_device *net,
1011 struct ethtool_link_ksettings *cmd)
1012 {
1013 struct usbnet *dev = netdev_priv(net);
1014
1015 /* the assumption that speed is equal on tx and rx
1016 * is deeply engrained into the networking layer.
1017 * For wireless stuff it is not true.
1018 * We assume that rx_speed matters more.
1019 */
1020 if (dev->rx_speed != SPEED_UNSET)
1021 cmd->base.speed = dev->rx_speed / 1000000;
1022 else if (dev->tx_speed != SPEED_UNSET)
1023 cmd->base.speed = dev->tx_speed / 1000000;
1024 else
1025 cmd->base.speed = SPEED_UNKNOWN;
1026
1027 /* The standard "Universal Serial Bus Class Definitions
1028 * for Communications Devices v1.2" does not specify
1029 * anything about duplex status.
1030 * So set it DUPLEX_UNKNOWN instead of default DUPLEX_HALF.
1031 */
1032 cmd->base.duplex = DUPLEX_UNKNOWN;
1033
1034 return 0;
1035 }
1036 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1037
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1038 int usbnet_set_link_ksettings_mii(struct net_device *net,
1039 const struct ethtool_link_ksettings *cmd)
1040 {
1041 struct usbnet *dev = netdev_priv(net);
1042 int retval;
1043
1044 if (!dev->mii.mdio_write)
1045 return -EOPNOTSUPP;
1046
1047 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1048
1049 /* link speed/duplex might have changed */
1050 if (dev->driver_info->link_reset)
1051 dev->driver_info->link_reset(dev);
1052
1053 /* hard_mtu or rx_urb_size may change in link_reset() */
1054 usbnet_update_max_qlen(dev);
1055
1056 return retval;
1057 }
1058 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1059
usbnet_get_link(struct net_device * net)1060 u32 usbnet_get_link(struct net_device *net)
1061 {
1062 struct usbnet *dev = netdev_priv(net);
1063
1064 /* If a check_connect is defined, return its result */
1065 if (dev->driver_info->check_connect)
1066 return dev->driver_info->check_connect(dev) == 0;
1067
1068 /* if the device has mii operations, use those */
1069 if (dev->mii.mdio_read)
1070 return mii_link_ok(&dev->mii);
1071
1072 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1073 return ethtool_op_get_link(net);
1074 }
1075 EXPORT_SYMBOL_GPL(usbnet_get_link);
1076
usbnet_nway_reset(struct net_device * net)1077 int usbnet_nway_reset(struct net_device *net)
1078 {
1079 struct usbnet *dev = netdev_priv(net);
1080
1081 if (!dev->mii.mdio_write)
1082 return -EOPNOTSUPP;
1083
1084 return mii_nway_restart(&dev->mii);
1085 }
1086 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1087
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1088 void usbnet_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
1089 {
1090 struct usbnet *dev = netdev_priv(net);
1091
1092 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1093 strscpy(info->fw_version, dev->driver_info->description,
1094 sizeof(info->fw_version));
1095 usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
1096 }
1097 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1098
usbnet_get_msglevel(struct net_device * net)1099 u32 usbnet_get_msglevel(struct net_device *net)
1100 {
1101 struct usbnet *dev = netdev_priv(net);
1102
1103 return dev->msg_enable;
1104 }
1105 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1106
usbnet_set_msglevel(struct net_device * net,u32 level)1107 void usbnet_set_msglevel(struct net_device *net, u32 level)
1108 {
1109 struct usbnet *dev = netdev_priv(net);
1110
1111 dev->msg_enable = level;
1112 }
1113 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1114
1115 /* drivers may override default ethtool_ops in their bind() routine */
1116 static const struct ethtool_ops usbnet_ethtool_ops = {
1117 .get_link = usbnet_get_link,
1118 .nway_reset = usbnet_nway_reset,
1119 .get_drvinfo = usbnet_get_drvinfo,
1120 .get_msglevel = usbnet_get_msglevel,
1121 .set_msglevel = usbnet_set_msglevel,
1122 .get_ts_info = ethtool_op_get_ts_info,
1123 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1124 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1125 };
1126
1127 /*-------------------------------------------------------------------------*/
1128
__handle_link_change(struct usbnet * dev)1129 static void __handle_link_change(struct usbnet *dev)
1130 {
1131 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1132 return;
1133
1134 if (test_and_clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags))
1135 netif_carrier_on(dev->net);
1136
1137 if (!netif_carrier_ok(dev->net)) {
1138 /* kill URBs for reading packets to save bus bandwidth */
1139 unlink_urbs(dev, &dev->rxq);
1140
1141 /*
1142 * tx_timeout will unlink URBs for sending packets and
1143 * tx queue is stopped by netcore after link becomes off
1144 */
1145 } else {
1146 /* submitting URBs for reading packets */
1147 queue_work(system_bh_wq, &dev->bh_work);
1148 }
1149
1150 /* hard_mtu or rx_urb_size may change during link change */
1151 usbnet_update_max_qlen(dev);
1152
1153 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1154 }
1155
usbnet_set_rx_mode(struct net_device * net)1156 void usbnet_set_rx_mode(struct net_device *net)
1157 {
1158 struct usbnet *dev = netdev_priv(net);
1159
1160 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1161 }
1162 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1163
__handle_set_rx_mode(struct usbnet * dev)1164 static void __handle_set_rx_mode(struct usbnet *dev)
1165 {
1166 if (dev->driver_info->set_rx_mode)
1167 (dev->driver_info->set_rx_mode)(dev);
1168
1169 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1170 }
1171
1172 /* work that cannot be done in interrupt context uses keventd.
1173 *
1174 * NOTE: with 2.5 we could do more of this using completion callbacks,
1175 * especially now that control transfers can be queued.
1176 */
1177 static void
usbnet_deferred_kevent(struct work_struct * work)1178 usbnet_deferred_kevent(struct work_struct *work)
1179 {
1180 struct usbnet *dev =
1181 container_of(work, struct usbnet, kevent);
1182 int status;
1183
1184 /* usb_clear_halt() needs a thread context */
1185 if (test_bit(EVENT_TX_HALT, &dev->flags)) {
1186 unlink_urbs(dev, &dev->txq);
1187 status = usb_autopm_get_interface(dev->intf);
1188 if (status < 0)
1189 goto fail_pipe;
1190 status = usb_clear_halt(dev->udev, dev->out);
1191 usb_autopm_put_interface(dev->intf);
1192 if (status < 0 &&
1193 status != -EPIPE &&
1194 status != -ESHUTDOWN) {
1195 if (netif_msg_tx_err(dev))
1196 fail_pipe:
1197 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1198 status);
1199 } else {
1200 clear_bit(EVENT_TX_HALT, &dev->flags);
1201 if (status != -ESHUTDOWN)
1202 netif_wake_queue(dev->net);
1203 }
1204 }
1205 if (test_bit(EVENT_RX_HALT, &dev->flags)) {
1206 unlink_urbs(dev, &dev->rxq);
1207 status = usb_autopm_get_interface(dev->intf);
1208 if (status < 0)
1209 goto fail_halt;
1210 status = usb_clear_halt(dev->udev, dev->in);
1211 usb_autopm_put_interface(dev->intf);
1212 if (status < 0 &&
1213 status != -EPIPE &&
1214 status != -ESHUTDOWN) {
1215 if (netif_msg_rx_err(dev))
1216 fail_halt:
1217 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1218 status);
1219 } else {
1220 clear_bit(EVENT_RX_HALT, &dev->flags);
1221 if (!usbnet_going_away(dev))
1222 queue_work(system_bh_wq, &dev->bh_work);
1223 }
1224 }
1225
1226 /* work could resubmit itself forever if memory is tight */
1227 if (test_bit(EVENT_RX_MEMORY, &dev->flags)) {
1228 struct urb *urb = NULL;
1229 int resched = 1;
1230
1231 if (netif_running(dev->net))
1232 urb = usb_alloc_urb(0, GFP_KERNEL);
1233 else
1234 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1235 if (urb != NULL) {
1236 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1237 status = usb_autopm_get_interface(dev->intf);
1238 if (status < 0) {
1239 usb_free_urb(urb);
1240 goto fail_lowmem;
1241 }
1242 if (rx_submit(dev, urb, GFP_KERNEL) == -ENOLINK)
1243 resched = 0;
1244 usb_autopm_put_interface(dev->intf);
1245 fail_lowmem:
1246 if (resched)
1247 if (!usbnet_going_away(dev))
1248 queue_work(system_bh_wq, &dev->bh_work);
1249 }
1250 }
1251
1252 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1253 const struct driver_info *info = dev->driver_info;
1254 int retval = 0;
1255
1256 clear_bit(EVENT_LINK_RESET, &dev->flags);
1257 status = usb_autopm_get_interface(dev->intf);
1258 if (status < 0)
1259 goto skip_reset;
1260 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1261 usb_autopm_put_interface(dev->intf);
1262 skip_reset:
1263 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1264 retval,
1265 dev->udev->bus->bus_name,
1266 dev->udev->devpath,
1267 info->description);
1268 } else {
1269 usb_autopm_put_interface(dev->intf);
1270 }
1271
1272 /* handle link change from link resetting */
1273 __handle_link_change(dev);
1274 }
1275
1276 if (test_bit(EVENT_LINK_CHANGE, &dev->flags))
1277 __handle_link_change(dev);
1278
1279 if (test_bit(EVENT_SET_RX_MODE, &dev->flags))
1280 __handle_set_rx_mode(dev);
1281
1282
1283 if (dev->flags)
1284 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1285 }
1286
1287 /*-------------------------------------------------------------------------*/
1288
tx_complete(struct urb * urb)1289 static void tx_complete(struct urb *urb)
1290 {
1291 struct sk_buff *skb = (struct sk_buff *) urb->context;
1292 struct skb_data *entry = (struct skb_data *) skb->cb;
1293 struct usbnet *dev = entry->dev;
1294
1295 if (urb->status == 0) {
1296 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1297 unsigned long flags;
1298
1299 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1300 u64_stats_add(&stats64->tx_packets, entry->packets);
1301 u64_stats_add(&stats64->tx_bytes, entry->length);
1302 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1303 } else {
1304 dev->net->stats.tx_errors++;
1305
1306 switch (urb->status) {
1307 case -EPIPE:
1308 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1309 break;
1310
1311 /* software-driven interface shutdown */
1312 case -ECONNRESET: // async unlink
1313 case -ESHUTDOWN: // hardware gone
1314 break;
1315
1316 /* like rx, tx gets controller i/o faults during hub_wq
1317 * delays and so it uses the same throttling mechanism.
1318 */
1319 case -EPROTO:
1320 case -ETIME:
1321 case -EILSEQ:
1322 usb_mark_last_busy(dev->udev);
1323 if (!timer_pending(&dev->delay)) {
1324 mod_timer(&dev->delay,
1325 jiffies + THROTTLE_JIFFIES);
1326 netif_dbg(dev, link, dev->net,
1327 "tx throttle %d\n", urb->status);
1328 }
1329 netif_stop_queue(dev->net);
1330 break;
1331 default:
1332 netif_dbg(dev, tx_err, dev->net,
1333 "tx err %d\n", entry->urb->status);
1334 break;
1335 }
1336 }
1337
1338 usb_autopm_put_interface_async(dev->intf);
1339 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1340 }
1341
1342 /*-------------------------------------------------------------------------*/
1343
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1344 void usbnet_tx_timeout(struct net_device *net, unsigned int txqueue)
1345 {
1346 struct usbnet *dev = netdev_priv(net);
1347
1348 unlink_urbs(dev, &dev->txq);
1349 queue_work(system_bh_wq, &dev->bh_work);
1350 /* this needs to be handled individually because the generic layer
1351 * doesn't know what is sufficient and could not restore private
1352 * information if a remedy of an unconditional reset were used.
1353 */
1354 if (dev->driver_info->recover)
1355 (dev->driver_info->recover)(dev);
1356 }
1357 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1358
1359 /*-------------------------------------------------------------------------*/
1360
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1361 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1362 {
1363 unsigned num_sgs, total_len = 0;
1364 int i, s = 0;
1365
1366 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1367 if (num_sgs == 1)
1368 return 0;
1369
1370 /* reserve one for zero packet */
1371 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1372 GFP_ATOMIC);
1373 if (!urb->sg)
1374 return -ENOMEM;
1375
1376 urb->num_sgs = num_sgs;
1377 sg_init_table(urb->sg, urb->num_sgs + 1);
1378
1379 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1380 total_len += skb_headlen(skb);
1381
1382 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1383 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1384
1385 total_len += skb_frag_size(f);
1386 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1387 skb_frag_off(f));
1388 }
1389 urb->transfer_buffer_length = total_len;
1390
1391 return 1;
1392 }
1393
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1394 netdev_tx_t usbnet_start_xmit(struct sk_buff *skb, struct net_device *net)
1395 {
1396 struct usbnet *dev = netdev_priv(net);
1397 unsigned int length;
1398 struct urb *urb = NULL;
1399 struct skb_data *entry;
1400 const struct driver_info *info = dev->driver_info;
1401 unsigned long flags;
1402 int retval;
1403
1404 if (skb)
1405 skb_tx_timestamp(skb);
1406
1407 // some devices want funky USB-level framing, for
1408 // win32 driver (usually) and/or hardware quirks
1409 if (info->tx_fixup) {
1410 skb = info->tx_fixup(dev, skb, GFP_ATOMIC);
1411 if (!skb) {
1412 /* packet collected; minidriver waiting for more */
1413 if (info->flags & FLAG_MULTI_PACKET)
1414 goto not_drop;
1415 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1416 goto drop;
1417 }
1418 }
1419
1420 urb = usb_alloc_urb(0, GFP_ATOMIC);
1421 if (!urb) {
1422 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1423 goto drop;
1424 }
1425
1426 entry = (struct skb_data *) skb->cb;
1427 entry->urb = urb;
1428 entry->dev = dev;
1429
1430 usb_fill_bulk_urb(urb, dev->udev, dev->out,
1431 skb->data, skb->len, tx_complete, skb);
1432 if (dev->can_dma_sg) {
1433 if (build_dma_sg(skb, urb) < 0)
1434 goto drop;
1435 }
1436 length = urb->transfer_buffer_length;
1437
1438 /* don't assume the hardware handles USB_ZERO_PACKET
1439 * NOTE: strictly conforming cdc-ether devices should expect
1440 * the ZLP here, but ignore the one-byte packet.
1441 * NOTE2: CDC NCM specification is different from CDC ECM when
1442 * handling ZLP/short packets, so cdc_ncm driver will make short
1443 * packet itself if needed.
1444 */
1445 if (length % dev->maxpacket == 0) {
1446 if (!(info->flags & FLAG_SEND_ZLP)) {
1447 if (!(info->flags & FLAG_MULTI_PACKET)) {
1448 length++;
1449 if (skb_tailroom(skb) && !urb->num_sgs) {
1450 skb->data[skb->len] = 0;
1451 __skb_put(skb, 1);
1452 } else if (urb->num_sgs)
1453 sg_set_buf(&urb->sg[urb->num_sgs++],
1454 dev->padding_pkt, 1);
1455 }
1456 } else
1457 urb->transfer_flags |= URB_ZERO_PACKET;
1458 }
1459 urb->transfer_buffer_length = length;
1460
1461 if (info->flags & FLAG_MULTI_PACKET) {
1462 /* Driver has set number of packets and a length delta.
1463 * Calculate the complete length and ensure that it's
1464 * positive.
1465 */
1466 entry->length += length;
1467 if (WARN_ON_ONCE(entry->length <= 0))
1468 entry->length = length;
1469 } else {
1470 usbnet_set_skb_tx_stats(skb, 1, length);
1471 }
1472
1473 spin_lock_irqsave(&dev->txq.lock, flags);
1474 retval = usb_autopm_get_interface_async(dev->intf);
1475 if (retval < 0) {
1476 spin_unlock_irqrestore(&dev->txq.lock, flags);
1477 goto drop;
1478 }
1479 if (netif_queue_stopped(net)) {
1480 usb_autopm_put_interface_async(dev->intf);
1481 spin_unlock_irqrestore(&dev->txq.lock, flags);
1482 goto drop;
1483 }
1484
1485 #ifdef CONFIG_PM
1486 /* if this triggers the device is still a sleep */
1487 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1488 /* transmission will be done in resume */
1489 usb_anchor_urb(urb, &dev->deferred);
1490 /* no use to process more packets */
1491 netif_stop_queue(net);
1492 usb_put_urb(urb);
1493 spin_unlock_irqrestore(&dev->txq.lock, flags);
1494 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1495 goto deferred;
1496 }
1497 #endif
1498
1499 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1500 case -EPIPE:
1501 netif_stop_queue(net);
1502 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1503 usb_autopm_put_interface_async(dev->intf);
1504 break;
1505 default:
1506 usb_autopm_put_interface_async(dev->intf);
1507 netif_dbg(dev, tx_err, dev->net,
1508 "tx: submit urb err %d\n", retval);
1509 break;
1510 case 0:
1511 netif_trans_update(net);
1512 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1513 netdev_sent_queue(net, skb->len);
1514 if (dev->txq.qlen >= TX_QLEN (dev))
1515 netif_stop_queue (net);
1516 }
1517 spin_unlock_irqrestore(&dev->txq.lock, flags);
1518
1519 if (retval) {
1520 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1521 drop:
1522 dev->net->stats.tx_dropped++;
1523 not_drop:
1524 if (skb)
1525 dev_kfree_skb_any(skb);
1526 if (urb) {
1527 kfree(urb->sg);
1528 usb_free_urb(urb);
1529 }
1530 } else
1531 netif_dbg(dev, tx_queued, dev->net,
1532 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1533 #ifdef CONFIG_PM
1534 deferred:
1535 #endif
1536 return NETDEV_TX_OK;
1537 }
1538 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1539
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1540 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1541 {
1542 struct urb *urb;
1543 int i;
1544 int ret = 0;
1545
1546 /* don't refill the queue all at once */
1547 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1548 urb = usb_alloc_urb(0, flags);
1549 if (urb != NULL) {
1550 ret = rx_submit(dev, urb, flags);
1551 if (ret)
1552 goto err;
1553 } else {
1554 ret = -ENOMEM;
1555 goto err;
1556 }
1557 }
1558 err:
1559 return ret;
1560 }
1561
usb_free_skb(struct sk_buff * skb)1562 static inline void usb_free_skb(struct sk_buff *skb)
1563 {
1564 struct skb_data *entry = (struct skb_data *)skb->cb;
1565
1566 usb_free_urb(entry->urb);
1567 dev_kfree_skb(skb);
1568 }
1569
1570 /*-------------------------------------------------------------------------*/
1571
1572 // work (work deferred from completions, in_irq) or timer
1573
usbnet_bh(struct timer_list * t)1574 static void usbnet_bh(struct timer_list *t)
1575 {
1576 struct usbnet *dev = timer_container_of(dev, t, delay);
1577 unsigned int bytes_compl = 0, pkts_compl = 0;
1578 struct sk_buff *skb;
1579 struct skb_data *entry;
1580
1581 while ((skb = skb_dequeue (&dev->done))) {
1582 entry = (struct skb_data *) skb->cb;
1583 switch (entry->state) {
1584 case rx_done:
1585 if (rx_process(dev, skb))
1586 usb_free_skb(skb);
1587 continue;
1588 case tx_done:
1589 bytes_compl += skb->len;
1590 pkts_compl++;
1591 kfree(entry->urb->sg);
1592 fallthrough;
1593 case rx_cleanup:
1594 usb_free_skb(skb);
1595 continue;
1596 default:
1597 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1598 }
1599 }
1600
1601 spin_lock_bh(&dev->bql_spinlock);
1602 netdev_completed_queue(dev->net, pkts_compl, bytes_compl);
1603 spin_unlock_bh(&dev->bql_spinlock);
1604
1605 /* restart RX again after disabling due to high error rate */
1606 clear_bit(EVENT_RX_KILL, &dev->flags);
1607
1608 /* waiting for all pending urbs to complete?
1609 * only then can we forgo submitting anew
1610 */
1611 if (waitqueue_active(&dev->wait)) {
1612 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1613 wake_up_all(&dev->wait);
1614
1615 // or are we maybe short a few urbs?
1616 } else if (netif_running (dev->net) &&
1617 netif_device_present (dev->net) &&
1618 netif_carrier_ok(dev->net) &&
1619 !usbnet_going_away(dev) &&
1620 !timer_pending(&dev->delay) &&
1621 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1622 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1623 int temp = dev->rxq.qlen;
1624
1625 if (temp < RX_QLEN(dev)) {
1626 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1627 return;
1628 if (temp != dev->rxq.qlen)
1629 netif_dbg(dev, link, dev->net,
1630 "rxqlen %d --> %d\n",
1631 temp, dev->rxq.qlen);
1632 if (dev->rxq.qlen < RX_QLEN(dev))
1633 queue_work(system_bh_wq, &dev->bh_work);
1634 }
1635 if (dev->txq.qlen < TX_QLEN (dev))
1636 netif_wake_queue(dev->net);
1637 }
1638 }
1639
usbnet_bh_work(struct work_struct * work)1640 static void usbnet_bh_work(struct work_struct *work)
1641 {
1642 struct usbnet *dev = from_work(dev, work, bh_work);
1643
1644 usbnet_bh(&dev->delay);
1645 }
1646
1647
1648 /*-------------------------------------------------------------------------
1649 *
1650 * USB Device Driver support
1651 *
1652 *-------------------------------------------------------------------------*/
1653
1654 // precondition: never called in_interrupt
1655
usbnet_disconnect(struct usb_interface * intf)1656 void usbnet_disconnect(struct usb_interface *intf)
1657 {
1658 struct usbnet *dev;
1659 struct usb_device *xdev;
1660 struct net_device *net;
1661 struct urb *urb;
1662
1663 dev = usb_get_intfdata(intf);
1664 usb_set_intfdata(intf, NULL);
1665 if (!dev)
1666 return;
1667 usbnet_mark_going_away(dev);
1668
1669 xdev = interface_to_usbdev(intf);
1670
1671 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1672 intf->dev.driver->name,
1673 xdev->bus->bus_name, xdev->devpath,
1674 dev->driver_info->description);
1675
1676 net = dev->net;
1677 unregister_netdev(net);
1678
1679 cancel_work_sync(&dev->kevent);
1680
1681 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1682 dev_kfree_skb(urb->context);
1683 kfree(urb->sg);
1684 usb_free_urb(urb);
1685 }
1686
1687 if (dev->driver_info->unbind)
1688 dev->driver_info->unbind(dev, intf);
1689
1690 usb_kill_urb(dev->interrupt);
1691 usb_free_urb(dev->interrupt);
1692 kfree(dev->padding_pkt);
1693
1694 free_netdev(net);
1695 }
1696 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1697
1698 static const struct net_device_ops usbnet_netdev_ops = {
1699 .ndo_open = usbnet_open,
1700 .ndo_stop = usbnet_stop,
1701 .ndo_start_xmit = usbnet_start_xmit,
1702 .ndo_tx_timeout = usbnet_tx_timeout,
1703 .ndo_set_rx_mode = usbnet_set_rx_mode,
1704 .ndo_change_mtu = usbnet_change_mtu,
1705 .ndo_set_mac_address = eth_mac_addr,
1706 .ndo_validate_addr = eth_validate_addr,
1707 };
1708
1709 /*-------------------------------------------------------------------------*/
1710
1711 // precondition: never called in_interrupt
1712
1713 static const struct device_type wlan_type = {
1714 .name = "wlan",
1715 };
1716
1717 static const struct device_type wwan_type = {
1718 .name = "wwan",
1719 };
1720
1721 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1722 usbnet_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1723 {
1724 struct usbnet *dev;
1725 struct net_device *net;
1726 struct usb_host_interface *interface;
1727 const struct driver_info *info;
1728 struct usb_device *xdev;
1729 int status;
1730 const char *name;
1731 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1732
1733 /* usbnet already took usb runtime pm, so have to enable the feature
1734 * for usb interface, otherwise usb_autopm_get_interface may return
1735 * failure if RUNTIME_PM is enabled.
1736 */
1737 if (!driver->supports_autosuspend) {
1738 driver->supports_autosuspend = 1;
1739 pm_runtime_enable(&udev->dev);
1740 }
1741
1742 name = udev->dev.driver->name;
1743 info = (const struct driver_info *) prod->driver_info;
1744 if (!info) {
1745 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1746 return -ENODEV;
1747 }
1748 xdev = interface_to_usbdev(udev);
1749 interface = udev->cur_altsetting;
1750
1751 status = -ENOMEM;
1752
1753 // set up our own records
1754 net = alloc_etherdev(sizeof(*dev));
1755 if (!net)
1756 goto out;
1757
1758 /* netdev_printk() needs this so do it as early as possible */
1759 SET_NETDEV_DEV(net, &udev->dev);
1760
1761 dev = netdev_priv(net);
1762 dev->udev = xdev;
1763 dev->intf = udev;
1764 dev->driver_info = info;
1765 dev->driver_name = name;
1766 dev->rx_speed = SPEED_UNSET;
1767 dev->tx_speed = SPEED_UNSET;
1768
1769 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1770 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1771 init_waitqueue_head(&dev->wait);
1772 skb_queue_head_init (&dev->rxq);
1773 skb_queue_head_init (&dev->txq);
1774 skb_queue_head_init (&dev->done);
1775 skb_queue_head_init(&dev->rxq_pause);
1776 spin_lock_init(&dev->bql_spinlock);
1777 INIT_WORK(&dev->bh_work, usbnet_bh_work);
1778 INIT_WORK(&dev->kevent, usbnet_deferred_kevent);
1779 init_usb_anchor(&dev->deferred);
1780 timer_setup(&dev->delay, usbnet_bh, 0);
1781 mutex_init(&dev->phy_mutex);
1782 mutex_init(&dev->interrupt_mutex);
1783 dev->interrupt_count = 0;
1784
1785 dev->net = net;
1786 strscpy(net->name, "usb%d", sizeof(net->name));
1787
1788 /* rx and tx sides can use different message sizes;
1789 * bind() should set rx_urb_size in that case.
1790 */
1791 dev->hard_mtu = net->mtu + net->hard_header_len;
1792 net->min_mtu = 0;
1793 net->max_mtu = ETH_MAX_MTU;
1794
1795 net->netdev_ops = &usbnet_netdev_ops;
1796 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1797 net->ethtool_ops = &usbnet_ethtool_ops;
1798 net->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1799
1800 // allow device-specific bind/init procedures
1801 // NOTE net->name still not usable ...
1802 if (info->bind) {
1803 status = info->bind(dev, udev);
1804 if (status < 0)
1805 goto out1;
1806
1807 /* heuristic: rename to "eth%d" if we are not sure this link
1808 * is two-host (these links keep "usb%d")
1809 */
1810 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1811 !usbnet_needs_usb_name_format(dev, net))
1812 strscpy(net->name, "eth%d", sizeof(net->name));
1813 /* WLAN devices should always be named "wlan%d" */
1814 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1815 strscpy(net->name, "wlan%d", sizeof(net->name));
1816 /* WWAN devices should always be named "wwan%d" */
1817 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1818 strscpy(net->name, "wwan%d", sizeof(net->name));
1819
1820 /* devices that cannot do ARP */
1821 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1822 net->flags |= IFF_NOARP;
1823
1824 /* maybe the remote can't receive an Ethernet MTU */
1825 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1826 net->mtu = dev->hard_mtu - net->hard_header_len;
1827 } else if (!info->in || !info->out)
1828 status = usbnet_get_endpoints(dev, udev);
1829 else {
1830 u8 ep_addrs[3] = {
1831 info->in + USB_DIR_IN, info->out + USB_DIR_OUT, 0
1832 };
1833
1834 dev->in = usb_rcvbulkpipe(xdev, info->in);
1835 dev->out = usb_sndbulkpipe(xdev, info->out);
1836 if (!(info->flags & FLAG_NO_SETINT))
1837 status = usb_set_interface(xdev,
1838 interface->desc.bInterfaceNumber,
1839 interface->desc.bAlternateSetting);
1840 else
1841 status = 0;
1842
1843 if (status == 0 && !usb_check_bulk_endpoints(udev, ep_addrs))
1844 status = -EINVAL;
1845 }
1846 if (status >= 0 && dev->status)
1847 status = init_status(dev, udev);
1848 if (status < 0)
1849 goto out3;
1850
1851 if (!dev->rx_urb_size)
1852 dev->rx_urb_size = dev->hard_mtu;
1853 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1854 if (dev->maxpacket == 0) {
1855 /* that is a broken device */
1856 status = -ENODEV;
1857 goto out4;
1858 }
1859
1860 /* this flags the device for user space */
1861 if (!is_valid_ether_addr(net->dev_addr))
1862 eth_hw_addr_random(net);
1863
1864 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1865 SET_NETDEV_DEVTYPE(net, &wlan_type);
1866 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1867 SET_NETDEV_DEVTYPE(net, &wwan_type);
1868
1869 /* initialize max rx_qlen and tx_qlen */
1870 usbnet_update_max_qlen(dev);
1871
1872 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1873 !(info->flags & FLAG_MULTI_PACKET)) {
1874 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1875 if (!dev->padding_pkt) {
1876 status = -ENOMEM;
1877 goto out4;
1878 }
1879 }
1880
1881 status = register_netdev(net);
1882 if (status)
1883 goto out5;
1884 netif_info(dev, probe, dev->net,
1885 "register '%s' at usb-%s-%s, %s, %pM\n",
1886 udev->dev.driver->name,
1887 xdev->bus->bus_name, xdev->devpath,
1888 dev->driver_info->description,
1889 net->dev_addr);
1890
1891 // ok, it's ready to go.
1892 usb_set_intfdata(udev, dev);
1893
1894 netif_device_attach(net);
1895
1896 if (dev->driver_info->flags & FLAG_LINK_INTR)
1897 usbnet_link_change(dev, 0, 0);
1898
1899 return 0;
1900
1901 out5:
1902 kfree(dev->padding_pkt);
1903 out4:
1904 usb_free_urb(dev->interrupt);
1905 out3:
1906 if (info->unbind)
1907 info->unbind(dev, udev);
1908 out1:
1909 /* subdrivers must undo all they did in bind() if they
1910 * fail it, but we may fail later and a deferred kevent
1911 * may trigger an error resubmitting itself and, worse,
1912 * schedule a timer. So we kill it all just in case.
1913 */
1914 usbnet_mark_going_away(dev);
1915 cancel_work_sync(&dev->kevent);
1916 timer_delete_sync(&dev->delay);
1917 free_netdev(net);
1918 out:
1919 return status;
1920 }
1921 EXPORT_SYMBOL_GPL(usbnet_probe);
1922
1923 /*-------------------------------------------------------------------------*/
1924
1925 /*
1926 * suspend the whole driver as soon as the first interface is suspended
1927 * resume only when the last interface is resumed
1928 */
1929
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1930 int usbnet_suspend(struct usb_interface *intf, pm_message_t message)
1931 {
1932 struct usbnet *dev = usb_get_intfdata(intf);
1933
1934 if (!dev->suspend_count++) {
1935 spin_lock_irq(&dev->txq.lock);
1936 /* don't autosuspend while transmitting */
1937 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1938 dev->suspend_count--;
1939 spin_unlock_irq(&dev->txq.lock);
1940 return -EBUSY;
1941 } else {
1942 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1943 spin_unlock_irq(&dev->txq.lock);
1944 }
1945 /*
1946 * accelerate emptying of the rx and queues, to avoid
1947 * having everything error out.
1948 */
1949 netif_device_detach(dev->net);
1950 usbnet_terminate_urbs(dev);
1951 __usbnet_status_stop_force(dev);
1952
1953 /*
1954 * reattach so runtime management can use and
1955 * wake the device
1956 */
1957 netif_device_attach(dev->net);
1958 }
1959 return 0;
1960 }
1961 EXPORT_SYMBOL_GPL(usbnet_suspend);
1962
usbnet_resume(struct usb_interface * intf)1963 int usbnet_resume(struct usb_interface *intf)
1964 {
1965 struct usbnet *dev = usb_get_intfdata(intf);
1966 struct sk_buff *skb;
1967 struct urb *res;
1968 int retval;
1969
1970 if (!--dev->suspend_count) {
1971 /* resume interrupt URB if it was previously submitted */
1972 __usbnet_status_start_force(dev, GFP_NOIO);
1973
1974 spin_lock_irq(&dev->txq.lock);
1975 while ((res = usb_get_from_anchor(&dev->deferred))) {
1976
1977 skb = (struct sk_buff *)res->context;
1978 retval = usb_submit_urb(res, GFP_ATOMIC);
1979 if (retval < 0) {
1980 dev_kfree_skb_any(skb);
1981 kfree(res->sg);
1982 usb_free_urb(res);
1983 usb_autopm_put_interface_async(dev->intf);
1984 } else {
1985 netif_trans_update(dev->net);
1986 __skb_queue_tail(&dev->txq, skb);
1987 }
1988 }
1989
1990 smp_mb();
1991 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1992 spin_unlock_irq(&dev->txq.lock);
1993
1994 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1995 /* handle remote wakeup ASAP
1996 * we cannot race against stop
1997 */
1998 if (netif_device_present(dev->net) &&
1999 !timer_pending(&dev->delay) &&
2000 !test_bit(EVENT_RX_HALT, &dev->flags))
2001 rx_alloc_submit(dev, GFP_NOIO);
2002
2003 if (!(dev->txq.qlen >= TX_QLEN(dev)))
2004 netif_tx_wake_all_queues(dev->net);
2005 queue_work(system_bh_wq, &dev->bh_work);
2006 }
2007 }
2008
2009 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
2010 usb_autopm_get_interface_no_resume(intf);
2011
2012 return 0;
2013 }
2014 EXPORT_SYMBOL_GPL(usbnet_resume);
2015
2016 /*
2017 * Either a subdriver implements manage_power, then it is assumed to always
2018 * be ready to be suspended or it reports the readiness to be suspended
2019 * explicitly
2020 */
usbnet_device_suggests_idle(struct usbnet * dev)2021 void usbnet_device_suggests_idle(struct usbnet *dev)
2022 {
2023 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
2024 dev->intf->needs_remote_wakeup = 1;
2025 usb_autopm_put_interface_async(dev->intf);
2026 }
2027 }
2028 EXPORT_SYMBOL(usbnet_device_suggests_idle);
2029
2030 /*
2031 * For devices that can do without special commands
2032 */
usbnet_manage_power(struct usbnet * dev,int on)2033 int usbnet_manage_power(struct usbnet *dev, int on)
2034 {
2035 dev->intf->needs_remote_wakeup = on;
2036 return 0;
2037 }
2038 EXPORT_SYMBOL(usbnet_manage_power);
2039
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)2040 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
2041 {
2042 /* update link after link is reseted */
2043 if (link && !need_reset) {
2044 set_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2045 } else {
2046 clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2047 netif_carrier_off(dev->net);
2048 }
2049
2050 if (need_reset && link)
2051 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
2052 else
2053 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
2054 }
2055 EXPORT_SYMBOL(usbnet_link_change);
2056
2057 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2058 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2059 u16 value, u16 index, void *data, u16 size)
2060 {
2061 void *buf = NULL;
2062 int err = -ENOMEM;
2063
2064 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2065 " value=0x%04x index=0x%04x size=%d\n",
2066 cmd, reqtype, value, index, size);
2067
2068 if (size) {
2069 buf = kmalloc(size, GFP_NOIO);
2070 if (!buf)
2071 goto out;
2072 }
2073
2074 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2075 cmd, reqtype, value, index, buf, size,
2076 USB_CTRL_GET_TIMEOUT);
2077 if (err > 0 && err <= size) {
2078 if (data)
2079 memcpy(data, buf, err);
2080 else
2081 netdev_dbg(dev->net,
2082 "Huh? Data requested but thrown away.\n");
2083 }
2084 kfree(buf);
2085 out:
2086 return err;
2087 }
2088
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2089 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2090 u16 value, u16 index, const void *data,
2091 u16 size)
2092 {
2093 void *buf = NULL;
2094 int err = -ENOMEM;
2095
2096 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2097 " value=0x%04x index=0x%04x size=%d\n",
2098 cmd, reqtype, value, index, size);
2099
2100 if (data) {
2101 buf = kmemdup(data, size, GFP_NOIO);
2102 if (!buf)
2103 goto out;
2104 } else {
2105 if (size) {
2106 WARN_ON_ONCE(1);
2107 err = -EINVAL;
2108 goto out;
2109 }
2110 }
2111
2112 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2113 cmd, reqtype, value, index, buf, size,
2114 USB_CTRL_SET_TIMEOUT);
2115 kfree(buf);
2116
2117 out:
2118 return err;
2119 }
2120
2121 /*
2122 * The function can't be called inside suspend/resume callback,
2123 * otherwise deadlock will be caused.
2124 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2125 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2126 u16 value, u16 index, void *data, u16 size)
2127 {
2128 int ret;
2129
2130 if (usb_autopm_get_interface(dev->intf) < 0)
2131 return -ENODEV;
2132 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2133 data, size);
2134 usb_autopm_put_interface(dev->intf);
2135 return ret;
2136 }
2137 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2138
2139 /*
2140 * The function can't be called inside suspend/resume callback,
2141 * otherwise deadlock will be caused.
2142 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2143 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2144 u16 value, u16 index, const void *data, u16 size)
2145 {
2146 int ret;
2147
2148 if (usb_autopm_get_interface(dev->intf) < 0)
2149 return -ENODEV;
2150 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2151 data, size);
2152 usb_autopm_put_interface(dev->intf);
2153 return ret;
2154 }
2155 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2156
2157 /*
2158 * The function can be called inside suspend/resume callback safely
2159 * and should only be called by suspend/resume callback generally.
2160 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2161 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2162 u16 value, u16 index, void *data, u16 size)
2163 {
2164 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2165 data, size);
2166 }
2167 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2168
2169 /*
2170 * The function can be called inside suspend/resume callback safely
2171 * and should only be called by suspend/resume callback generally.
2172 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2173 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2174 u16 value, u16 index, const void *data,
2175 u16 size)
2176 {
2177 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2178 data, size);
2179 }
2180 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2181
usbnet_async_cmd_cb(struct urb * urb)2182 static void usbnet_async_cmd_cb(struct urb *urb)
2183 {
2184 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2185 int status = urb->status;
2186
2187 if (status < 0)
2188 dev_dbg(&urb->dev->dev, "%s failed with %d",
2189 __func__, status);
2190
2191 kfree(req);
2192 usb_free_urb(urb);
2193 }
2194
2195 /*
2196 * The caller must make sure that device can't be put into suspend
2197 * state until the control URB completes.
2198 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2199 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2200 u16 value, u16 index, const void *data, u16 size)
2201 {
2202 struct usb_ctrlrequest *req;
2203 struct urb *urb;
2204 int err = -ENOMEM;
2205 void *buf = NULL;
2206
2207 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2208 " value=0x%04x index=0x%04x size=%d\n",
2209 cmd, reqtype, value, index, size);
2210
2211 urb = usb_alloc_urb(0, GFP_ATOMIC);
2212 if (!urb)
2213 goto fail;
2214
2215 if (data) {
2216 buf = kmemdup(data, size, GFP_ATOMIC);
2217 if (!buf) {
2218 netdev_err(dev->net, "Error allocating buffer"
2219 " in %s!\n", __func__);
2220 goto fail_free_urb;
2221 }
2222 }
2223
2224 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2225 if (!req)
2226 goto fail_free_buf;
2227
2228 req->bRequestType = reqtype;
2229 req->bRequest = cmd;
2230 req->wValue = cpu_to_le16(value);
2231 req->wIndex = cpu_to_le16(index);
2232 req->wLength = cpu_to_le16(size);
2233
2234 usb_fill_control_urb(urb, dev->udev,
2235 usb_sndctrlpipe(dev->udev, 0),
2236 (void *)req, buf, size,
2237 usbnet_async_cmd_cb, req);
2238 urb->transfer_flags |= URB_FREE_BUFFER;
2239
2240 err = usb_submit_urb(urb, GFP_ATOMIC);
2241 if (err < 0) {
2242 netdev_err(dev->net, "Error submitting the control"
2243 " message: status=%d\n", err);
2244 goto fail_free_all;
2245 }
2246 return 0;
2247
2248 fail_free_all:
2249 kfree(req);
2250 fail_free_buf:
2251 kfree(buf);
2252 /*
2253 * avoid a double free
2254 * needed because the flag can be set only
2255 * after filling the URB
2256 */
2257 urb->transfer_flags = 0;
2258 fail_free_urb:
2259 usb_free_urb(urb);
2260 fail:
2261 return err;
2262
2263 }
2264 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2265 /*-------------------------------------------------------------------------*/
2266
usbnet_init(void)2267 static int __init usbnet_init(void)
2268 {
2269 /* Compiler should optimize this out. */
2270 BUILD_BUG_ON(
2271 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2272
2273 return 0;
2274 }
2275 module_init(usbnet_init);
2276
usbnet_exit(void)2277 static void __exit usbnet_exit(void)
2278 {
2279 }
2280 module_exit(usbnet_exit);
2281
2282 MODULE_AUTHOR("David Brownell");
2283 MODULE_DESCRIPTION("USB network driver framework");
2284 MODULE_LICENSE("GPL");
2285