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 netdev_reset_queue(net);
835
836 netif_info(dev, ifdown, dev->net,
837 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
838 net->stats.rx_packets, net->stats.tx_packets,
839 net->stats.rx_errors, net->stats.tx_errors);
840
841 /* to not race resume */
842 pm = usb_autopm_get_interface(dev->intf);
843 /* allow minidriver to stop correctly (wireless devices to turn off
844 * radio etc) */
845 if (info->stop) {
846 retval = info->stop(dev);
847 if (retval < 0)
848 netif_info(dev, ifdown, dev->net,
849 "stop fail (%d) usbnet usb-%s-%s, %s\n",
850 retval,
851 dev->udev->bus->bus_name, dev->udev->devpath,
852 info->description);
853 }
854
855 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
856 usbnet_terminate_urbs(dev);
857
858 usbnet_status_stop(dev);
859
860 usbnet_purge_paused_rxq(dev);
861
862 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
863
864 /* deferred work (timer, softirq, task) must also stop */
865 dev->flags = 0;
866 timer_delete_sync(&dev->delay);
867 cancel_work_sync(&dev->bh_work);
868 cancel_work_sync(&dev->kevent);
869
870 /* We have cyclic dependencies. Those calls are needed
871 * to break a cycle. We cannot fall into the gaps because
872 * we have a flag
873 */
874 cancel_work_sync(&dev->bh_work);
875 timer_delete_sync(&dev->delay);
876 cancel_work_sync(&dev->kevent);
877
878 if (!pm)
879 usb_autopm_put_interface(dev->intf);
880
881 if (info->manage_power && mpn)
882 info->manage_power(dev, 0);
883 else
884 usb_autopm_put_interface(dev->intf);
885
886 return 0;
887 }
888 EXPORT_SYMBOL_GPL(usbnet_stop);
889
890 /*-------------------------------------------------------------------------*/
891
892 // posts reads, and enables write queuing
893
894 // precondition: never called in_interrupt
895
usbnet_open(struct net_device * net)896 int usbnet_open(struct net_device *net)
897 {
898 struct usbnet *dev = netdev_priv(net);
899 int retval;
900 const struct driver_info *info = dev->driver_info;
901
902 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
903 netif_info(dev, ifup, dev->net,
904 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
905 retval,
906 dev->udev->bus->bus_name,
907 dev->udev->devpath,
908 info->description);
909 goto done_nopm;
910 }
911
912 // put into "known safe" state
913 if (info->reset) {
914 retval = info->reset(dev);
915 if (retval < 0) {
916 netif_info(dev, ifup, dev->net,
917 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
918 retval,
919 dev->udev->bus->bus_name,
920 dev->udev->devpath,
921 info->description);
922 goto done;
923 }
924 }
925
926 /* hard_mtu or rx_urb_size may change in reset() */
927 usbnet_update_max_qlen(dev);
928
929 // insist peer be connected
930 if (info->check_connect) {
931 retval = info->check_connect(dev);
932 if (retval < 0) {
933 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
934 goto done;
935 }
936 }
937
938 /* start any status interrupt transfer */
939 if (dev->interrupt) {
940 retval = usbnet_status_start(dev, GFP_KERNEL);
941 if (retval < 0) {
942 netif_err(dev, ifup, dev->net,
943 "intr submit %d\n", retval);
944 goto done;
945 }
946 }
947
948 set_bit(EVENT_DEV_OPEN, &dev->flags);
949 netdev_reset_queue(net);
950 netif_start_queue (net);
951 netif_info(dev, ifup, dev->net,
952 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
953 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
954 dev->net->mtu,
955 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
956 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
957 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
958 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
959 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
960 "simple");
961
962 /* reset rx error state */
963 dev->pkt_cnt = 0;
964 dev->pkt_err = 0;
965 clear_bit(EVENT_RX_KILL, &dev->flags);
966
967 // delay posting reads until we're fully open
968 queue_work(system_bh_wq, &dev->bh_work);
969 if (info->manage_power) {
970 retval = info->manage_power(dev, 1);
971 if (retval < 0) {
972 retval = 0;
973 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
974 } else {
975 usb_autopm_put_interface(dev->intf);
976 }
977 }
978 return retval;
979 done:
980 usb_autopm_put_interface(dev->intf);
981 done_nopm:
982 return retval;
983 }
984 EXPORT_SYMBOL_GPL(usbnet_open);
985
986 /*-------------------------------------------------------------------------*/
987
988 /* ethtool methods; minidrivers may need to add some more, but
989 * they'll probably want to use this base set.
990 */
991
992 /* These methods are written on the assumption that the device
993 * uses MII
994 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)995 int usbnet_get_link_ksettings_mii(struct net_device *net,
996 struct ethtool_link_ksettings *cmd)
997 {
998 struct usbnet *dev = netdev_priv(net);
999
1000 if (!dev->mii.mdio_read)
1001 return -EOPNOTSUPP;
1002
1003 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
1004
1005 return 0;
1006 }
1007 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
1008
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)1009 int usbnet_get_link_ksettings_internal(struct net_device *net,
1010 struct ethtool_link_ksettings *cmd)
1011 {
1012 struct usbnet *dev = netdev_priv(net);
1013
1014 /* the assumption that speed is equal on tx and rx
1015 * is deeply engrained into the networking layer.
1016 * For wireless stuff it is not true.
1017 * We assume that rx_speed matters more.
1018 */
1019 if (dev->rx_speed != SPEED_UNSET)
1020 cmd->base.speed = dev->rx_speed / 1000000;
1021 else if (dev->tx_speed != SPEED_UNSET)
1022 cmd->base.speed = dev->tx_speed / 1000000;
1023 else
1024 cmd->base.speed = SPEED_UNKNOWN;
1025
1026 /* The standard "Universal Serial Bus Class Definitions
1027 * for Communications Devices v1.2" does not specify
1028 * anything about duplex status.
1029 * So set it DUPLEX_UNKNOWN instead of default DUPLEX_HALF.
1030 */
1031 cmd->base.duplex = DUPLEX_UNKNOWN;
1032
1033 return 0;
1034 }
1035 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1036
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1037 int usbnet_set_link_ksettings_mii(struct net_device *net,
1038 const struct ethtool_link_ksettings *cmd)
1039 {
1040 struct usbnet *dev = netdev_priv(net);
1041 int retval;
1042
1043 if (!dev->mii.mdio_write)
1044 return -EOPNOTSUPP;
1045
1046 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1047
1048 /* link speed/duplex might have changed */
1049 if (dev->driver_info->link_reset)
1050 dev->driver_info->link_reset(dev);
1051
1052 /* hard_mtu or rx_urb_size may change in link_reset() */
1053 usbnet_update_max_qlen(dev);
1054
1055 return retval;
1056 }
1057 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1058
usbnet_get_link(struct net_device * net)1059 u32 usbnet_get_link(struct net_device *net)
1060 {
1061 struct usbnet *dev = netdev_priv(net);
1062
1063 /* If a check_connect is defined, return its result */
1064 if (dev->driver_info->check_connect)
1065 return dev->driver_info->check_connect(dev) == 0;
1066
1067 /* if the device has mii operations, use those */
1068 if (dev->mii.mdio_read)
1069 return mii_link_ok(&dev->mii);
1070
1071 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1072 return ethtool_op_get_link(net);
1073 }
1074 EXPORT_SYMBOL_GPL(usbnet_get_link);
1075
usbnet_nway_reset(struct net_device * net)1076 int usbnet_nway_reset(struct net_device *net)
1077 {
1078 struct usbnet *dev = netdev_priv(net);
1079
1080 if (!dev->mii.mdio_write)
1081 return -EOPNOTSUPP;
1082
1083 return mii_nway_restart(&dev->mii);
1084 }
1085 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1086
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1087 void usbnet_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
1088 {
1089 struct usbnet *dev = netdev_priv(net);
1090
1091 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1092 strscpy(info->fw_version, dev->driver_info->description,
1093 sizeof(info->fw_version));
1094 usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
1095 }
1096 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1097
usbnet_get_msglevel(struct net_device * net)1098 u32 usbnet_get_msglevel(struct net_device *net)
1099 {
1100 struct usbnet *dev = netdev_priv(net);
1101
1102 return dev->msg_enable;
1103 }
1104 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1105
usbnet_set_msglevel(struct net_device * net,u32 level)1106 void usbnet_set_msglevel(struct net_device *net, u32 level)
1107 {
1108 struct usbnet *dev = netdev_priv(net);
1109
1110 dev->msg_enable = level;
1111 }
1112 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1113
1114 /* drivers may override default ethtool_ops in their bind() routine */
1115 static const struct ethtool_ops usbnet_ethtool_ops = {
1116 .get_link = usbnet_get_link,
1117 .nway_reset = usbnet_nway_reset,
1118 .get_drvinfo = usbnet_get_drvinfo,
1119 .get_msglevel = usbnet_get_msglevel,
1120 .set_msglevel = usbnet_set_msglevel,
1121 .get_ts_info = ethtool_op_get_ts_info,
1122 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1123 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1124 };
1125
1126 /*-------------------------------------------------------------------------*/
1127
__handle_link_change(struct usbnet * dev)1128 static void __handle_link_change(struct usbnet *dev)
1129 {
1130 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1131 return;
1132
1133 if (test_and_clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags))
1134 netif_carrier_on(dev->net);
1135
1136 if (!netif_carrier_ok(dev->net)) {
1137 /* kill URBs for reading packets to save bus bandwidth */
1138 unlink_urbs(dev, &dev->rxq);
1139
1140 /*
1141 * tx_timeout will unlink URBs for sending packets and
1142 * tx queue is stopped by netcore after link becomes off
1143 */
1144 } else {
1145 /* submitting URBs for reading packets */
1146 queue_work(system_bh_wq, &dev->bh_work);
1147 }
1148
1149 /* hard_mtu or rx_urb_size may change during link change */
1150 usbnet_update_max_qlen(dev);
1151
1152 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1153 }
1154
usbnet_set_rx_mode(struct net_device * net)1155 void usbnet_set_rx_mode(struct net_device *net)
1156 {
1157 struct usbnet *dev = netdev_priv(net);
1158
1159 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1160 }
1161 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1162
__handle_set_rx_mode(struct usbnet * dev)1163 static void __handle_set_rx_mode(struct usbnet *dev)
1164 {
1165 if (dev->driver_info->set_rx_mode)
1166 (dev->driver_info->set_rx_mode)(dev);
1167
1168 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1169 }
1170
1171 /* work that cannot be done in interrupt context uses keventd.
1172 *
1173 * NOTE: with 2.5 we could do more of this using completion callbacks,
1174 * especially now that control transfers can be queued.
1175 */
1176 static void
usbnet_deferred_kevent(struct work_struct * work)1177 usbnet_deferred_kevent(struct work_struct *work)
1178 {
1179 struct usbnet *dev =
1180 container_of(work, struct usbnet, kevent);
1181 int status;
1182
1183 /* usb_clear_halt() needs a thread context */
1184 if (test_bit(EVENT_TX_HALT, &dev->flags)) {
1185 unlink_urbs(dev, &dev->txq);
1186 status = usb_autopm_get_interface(dev->intf);
1187 if (status < 0)
1188 goto fail_pipe;
1189 status = usb_clear_halt(dev->udev, dev->out);
1190 usb_autopm_put_interface(dev->intf);
1191 if (status < 0 &&
1192 status != -EPIPE &&
1193 status != -ESHUTDOWN) {
1194 if (netif_msg_tx_err(dev))
1195 fail_pipe:
1196 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1197 status);
1198 } else {
1199 clear_bit(EVENT_TX_HALT, &dev->flags);
1200 if (status != -ESHUTDOWN)
1201 netif_wake_queue(dev->net);
1202 }
1203 }
1204 if (test_bit(EVENT_RX_HALT, &dev->flags)) {
1205 unlink_urbs(dev, &dev->rxq);
1206 status = usb_autopm_get_interface(dev->intf);
1207 if (status < 0)
1208 goto fail_halt;
1209 status = usb_clear_halt(dev->udev, dev->in);
1210 usb_autopm_put_interface(dev->intf);
1211 if (status < 0 &&
1212 status != -EPIPE &&
1213 status != -ESHUTDOWN) {
1214 if (netif_msg_rx_err(dev))
1215 fail_halt:
1216 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1217 status);
1218 } else {
1219 clear_bit(EVENT_RX_HALT, &dev->flags);
1220 if (!usbnet_going_away(dev))
1221 queue_work(system_bh_wq, &dev->bh_work);
1222 }
1223 }
1224
1225 /* work could resubmit itself forever if memory is tight */
1226 if (test_bit(EVENT_RX_MEMORY, &dev->flags)) {
1227 struct urb *urb = NULL;
1228 int resched = 1;
1229
1230 if (netif_running(dev->net))
1231 urb = usb_alloc_urb(0, GFP_KERNEL);
1232 else
1233 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1234 if (urb != NULL) {
1235 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1236 status = usb_autopm_get_interface(dev->intf);
1237 if (status < 0) {
1238 usb_free_urb(urb);
1239 goto fail_lowmem;
1240 }
1241 if (rx_submit(dev, urb, GFP_KERNEL) == -ENOLINK)
1242 resched = 0;
1243 usb_autopm_put_interface(dev->intf);
1244 fail_lowmem:
1245 if (resched)
1246 if (!usbnet_going_away(dev))
1247 queue_work(system_bh_wq, &dev->bh_work);
1248 }
1249 }
1250
1251 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1252 const struct driver_info *info = dev->driver_info;
1253 int retval = 0;
1254
1255 clear_bit(EVENT_LINK_RESET, &dev->flags);
1256 status = usb_autopm_get_interface(dev->intf);
1257 if (status < 0)
1258 goto skip_reset;
1259 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1260 usb_autopm_put_interface(dev->intf);
1261 skip_reset:
1262 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1263 retval,
1264 dev->udev->bus->bus_name,
1265 dev->udev->devpath,
1266 info->description);
1267 } else {
1268 usb_autopm_put_interface(dev->intf);
1269 }
1270
1271 /* handle link change from link resetting */
1272 __handle_link_change(dev);
1273 }
1274
1275 if (test_bit(EVENT_LINK_CHANGE, &dev->flags))
1276 __handle_link_change(dev);
1277
1278 if (test_bit(EVENT_SET_RX_MODE, &dev->flags))
1279 __handle_set_rx_mode(dev);
1280
1281
1282 if (dev->flags)
1283 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1284 }
1285
1286 /*-------------------------------------------------------------------------*/
1287
tx_complete(struct urb * urb)1288 static void tx_complete(struct urb *urb)
1289 {
1290 struct sk_buff *skb = (struct sk_buff *) urb->context;
1291 struct skb_data *entry = (struct skb_data *) skb->cb;
1292 struct usbnet *dev = entry->dev;
1293
1294 if (urb->status == 0) {
1295 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1296 unsigned long flags;
1297
1298 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1299 u64_stats_add(&stats64->tx_packets, entry->packets);
1300 u64_stats_add(&stats64->tx_bytes, entry->length);
1301 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1302 } else {
1303 dev->net->stats.tx_errors++;
1304
1305 switch (urb->status) {
1306 case -EPIPE:
1307 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1308 break;
1309
1310 /* software-driven interface shutdown */
1311 case -ECONNRESET: // async unlink
1312 case -ESHUTDOWN: // hardware gone
1313 break;
1314
1315 /* like rx, tx gets controller i/o faults during hub_wq
1316 * delays and so it uses the same throttling mechanism.
1317 */
1318 case -EPROTO:
1319 case -ETIME:
1320 case -EILSEQ:
1321 usb_mark_last_busy(dev->udev);
1322 if (!timer_pending(&dev->delay)) {
1323 mod_timer(&dev->delay,
1324 jiffies + THROTTLE_JIFFIES);
1325 netif_dbg(dev, link, dev->net,
1326 "tx throttle %d\n", urb->status);
1327 }
1328 netif_stop_queue(dev->net);
1329 break;
1330 default:
1331 netif_dbg(dev, tx_err, dev->net,
1332 "tx err %d\n", entry->urb->status);
1333 break;
1334 }
1335 }
1336
1337 usb_autopm_put_interface_async(dev->intf);
1338 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1339 }
1340
1341 /*-------------------------------------------------------------------------*/
1342
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1343 void usbnet_tx_timeout(struct net_device *net, unsigned int txqueue)
1344 {
1345 struct usbnet *dev = netdev_priv(net);
1346
1347 unlink_urbs(dev, &dev->txq);
1348 queue_work(system_bh_wq, &dev->bh_work);
1349 /* this needs to be handled individually because the generic layer
1350 * doesn't know what is sufficient and could not restore private
1351 * information if a remedy of an unconditional reset were used.
1352 */
1353 if (dev->driver_info->recover)
1354 (dev->driver_info->recover)(dev);
1355 }
1356 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1357
1358 /*-------------------------------------------------------------------------*/
1359
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1360 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1361 {
1362 unsigned num_sgs, total_len = 0;
1363 int i, s = 0;
1364
1365 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1366 if (num_sgs == 1)
1367 return 0;
1368
1369 /* reserve one for zero packet */
1370 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1371 GFP_ATOMIC);
1372 if (!urb->sg)
1373 return -ENOMEM;
1374
1375 urb->num_sgs = num_sgs;
1376 sg_init_table(urb->sg, urb->num_sgs + 1);
1377
1378 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1379 total_len += skb_headlen(skb);
1380
1381 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1382 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1383
1384 total_len += skb_frag_size(f);
1385 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1386 skb_frag_off(f));
1387 }
1388 urb->transfer_buffer_length = total_len;
1389
1390 return 1;
1391 }
1392
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1393 netdev_tx_t usbnet_start_xmit(struct sk_buff *skb, struct net_device *net)
1394 {
1395 struct usbnet *dev = netdev_priv(net);
1396 unsigned int length;
1397 struct urb *urb = NULL;
1398 struct skb_data *entry;
1399 const struct driver_info *info = dev->driver_info;
1400 unsigned long flags;
1401 int retval;
1402
1403 if (skb)
1404 skb_tx_timestamp(skb);
1405
1406 // some devices want funky USB-level framing, for
1407 // win32 driver (usually) and/or hardware quirks
1408 if (info->tx_fixup) {
1409 skb = info->tx_fixup(dev, skb, GFP_ATOMIC);
1410 if (!skb) {
1411 /* packet collected; minidriver waiting for more */
1412 if (info->flags & FLAG_MULTI_PACKET)
1413 goto not_drop;
1414 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1415 goto drop;
1416 }
1417 }
1418
1419 urb = usb_alloc_urb(0, GFP_ATOMIC);
1420 if (!urb) {
1421 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1422 goto drop;
1423 }
1424
1425 entry = (struct skb_data *) skb->cb;
1426 entry->urb = urb;
1427 entry->dev = dev;
1428
1429 usb_fill_bulk_urb(urb, dev->udev, dev->out,
1430 skb->data, skb->len, tx_complete, skb);
1431 if (dev->can_dma_sg) {
1432 if (build_dma_sg(skb, urb) < 0)
1433 goto drop;
1434 }
1435 length = urb->transfer_buffer_length;
1436
1437 /* don't assume the hardware handles USB_ZERO_PACKET
1438 * NOTE: strictly conforming cdc-ether devices should expect
1439 * the ZLP here, but ignore the one-byte packet.
1440 * NOTE2: CDC NCM specification is different from CDC ECM when
1441 * handling ZLP/short packets, so cdc_ncm driver will make short
1442 * packet itself if needed.
1443 */
1444 if (length % dev->maxpacket == 0) {
1445 if (!(info->flags & FLAG_SEND_ZLP)) {
1446 if (!(info->flags & FLAG_MULTI_PACKET)) {
1447 length++;
1448 if (skb_tailroom(skb) && !urb->num_sgs) {
1449 skb->data[skb->len] = 0;
1450 __skb_put(skb, 1);
1451 } else if (urb->num_sgs)
1452 sg_set_buf(&urb->sg[urb->num_sgs++],
1453 dev->padding_pkt, 1);
1454 }
1455 } else
1456 urb->transfer_flags |= URB_ZERO_PACKET;
1457 }
1458 urb->transfer_buffer_length = length;
1459
1460 if (info->flags & FLAG_MULTI_PACKET) {
1461 /* Driver has set number of packets and a length delta.
1462 * Calculate the complete length and ensure that it's
1463 * positive.
1464 */
1465 entry->length += length;
1466 if (WARN_ON_ONCE(entry->length <= 0))
1467 entry->length = length;
1468 } else {
1469 usbnet_set_skb_tx_stats(skb, 1, length);
1470 }
1471
1472 spin_lock_irqsave(&dev->txq.lock, flags);
1473 retval = usb_autopm_get_interface_async(dev->intf);
1474 if (retval < 0) {
1475 spin_unlock_irqrestore(&dev->txq.lock, flags);
1476 goto drop;
1477 }
1478 if (netif_queue_stopped(net)) {
1479 usb_autopm_put_interface_async(dev->intf);
1480 spin_unlock_irqrestore(&dev->txq.lock, flags);
1481 goto drop;
1482 }
1483
1484 #ifdef CONFIG_PM
1485 /* if this triggers the device is still a sleep */
1486 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1487 /* transmission will be done in resume */
1488 usb_anchor_urb(urb, &dev->deferred);
1489 /* no use to process more packets */
1490 netif_stop_queue(net);
1491 usb_put_urb(urb);
1492 spin_unlock_irqrestore(&dev->txq.lock, flags);
1493 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1494 goto deferred;
1495 }
1496 #endif
1497
1498 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1499 case -EPIPE:
1500 netif_stop_queue(net);
1501 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1502 usb_autopm_put_interface_async(dev->intf);
1503 break;
1504 default:
1505 usb_autopm_put_interface_async(dev->intf);
1506 netif_dbg(dev, tx_err, dev->net,
1507 "tx: submit urb err %d\n", retval);
1508 break;
1509 case 0:
1510 netif_trans_update(net);
1511 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1512 netdev_sent_queue(net, skb->len);
1513 if (dev->txq.qlen >= TX_QLEN (dev))
1514 netif_stop_queue (net);
1515 }
1516 spin_unlock_irqrestore(&dev->txq.lock, flags);
1517
1518 if (retval) {
1519 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1520 drop:
1521 dev->net->stats.tx_dropped++;
1522 not_drop:
1523 if (skb)
1524 dev_kfree_skb_any(skb);
1525 if (urb) {
1526 kfree(urb->sg);
1527 usb_free_urb(urb);
1528 }
1529 } else
1530 netif_dbg(dev, tx_queued, dev->net,
1531 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1532 #ifdef CONFIG_PM
1533 deferred:
1534 #endif
1535 return NETDEV_TX_OK;
1536 }
1537 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1538
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1539 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1540 {
1541 struct urb *urb;
1542 int i;
1543 int ret = 0;
1544
1545 /* don't refill the queue all at once */
1546 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1547 urb = usb_alloc_urb(0, flags);
1548 if (urb != NULL) {
1549 ret = rx_submit(dev, urb, flags);
1550 if (ret)
1551 goto err;
1552 } else {
1553 ret = -ENOMEM;
1554 goto err;
1555 }
1556 }
1557 err:
1558 return ret;
1559 }
1560
usb_free_skb(struct sk_buff * skb)1561 static inline void usb_free_skb(struct sk_buff *skb)
1562 {
1563 struct skb_data *entry = (struct skb_data *)skb->cb;
1564
1565 usb_free_urb(entry->urb);
1566 dev_kfree_skb(skb);
1567 }
1568
1569 /*-------------------------------------------------------------------------*/
1570
1571 // work (work deferred from completions, in_irq) or timer
1572
usbnet_bh(struct timer_list * t)1573 static void usbnet_bh(struct timer_list *t)
1574 {
1575 struct usbnet *dev = timer_container_of(dev, t, delay);
1576 unsigned int bytes_compl = 0, pkts_compl = 0;
1577 struct sk_buff *skb;
1578 struct skb_data *entry;
1579
1580 while ((skb = skb_dequeue (&dev->done))) {
1581 entry = (struct skb_data *) skb->cb;
1582 switch (entry->state) {
1583 case rx_done:
1584 if (rx_process(dev, skb))
1585 usb_free_skb(skb);
1586 continue;
1587 case tx_done:
1588 bytes_compl += skb->len;
1589 pkts_compl++;
1590 kfree(entry->urb->sg);
1591 fallthrough;
1592 case rx_cleanup:
1593 usb_free_skb(skb);
1594 continue;
1595 default:
1596 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1597 }
1598 }
1599
1600 spin_lock_bh(&dev->bql_spinlock);
1601 netdev_completed_queue(dev->net, pkts_compl, bytes_compl);
1602 spin_unlock_bh(&dev->bql_spinlock);
1603
1604 /* restart RX again after disabling due to high error rate */
1605 clear_bit(EVENT_RX_KILL, &dev->flags);
1606
1607 /* waiting for all pending urbs to complete?
1608 * only then can we forgo submitting anew
1609 */
1610 if (waitqueue_active(&dev->wait)) {
1611 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1612 wake_up_all(&dev->wait);
1613
1614 // or are we maybe short a few urbs?
1615 } else if (netif_running (dev->net) &&
1616 netif_device_present (dev->net) &&
1617 netif_carrier_ok(dev->net) &&
1618 !usbnet_going_away(dev) &&
1619 !timer_pending(&dev->delay) &&
1620 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1621 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1622 int temp = dev->rxq.qlen;
1623
1624 if (temp < RX_QLEN(dev)) {
1625 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1626 return;
1627 if (temp != dev->rxq.qlen)
1628 netif_dbg(dev, link, dev->net,
1629 "rxqlen %d --> %d\n",
1630 temp, dev->rxq.qlen);
1631 if (dev->rxq.qlen < RX_QLEN(dev))
1632 queue_work(system_bh_wq, &dev->bh_work);
1633 }
1634 if (dev->txq.qlen < TX_QLEN (dev))
1635 netif_wake_queue(dev->net);
1636 }
1637 }
1638
usbnet_bh_work(struct work_struct * work)1639 static void usbnet_bh_work(struct work_struct *work)
1640 {
1641 struct usbnet *dev = from_work(dev, work, bh_work);
1642
1643 usbnet_bh(&dev->delay);
1644 }
1645
1646
1647 /*-------------------------------------------------------------------------
1648 *
1649 * USB Device Driver support
1650 *
1651 *-------------------------------------------------------------------------*/
1652
1653 // precondition: never called in_interrupt
1654
usbnet_disconnect(struct usb_interface * intf)1655 void usbnet_disconnect(struct usb_interface *intf)
1656 {
1657 struct usbnet *dev;
1658 struct usb_device *xdev;
1659 struct net_device *net;
1660 struct urb *urb;
1661
1662 dev = usb_get_intfdata(intf);
1663 usb_set_intfdata(intf, NULL);
1664 if (!dev)
1665 return;
1666 usbnet_mark_going_away(dev);
1667
1668 xdev = interface_to_usbdev(intf);
1669
1670 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1671 intf->dev.driver->name,
1672 xdev->bus->bus_name, xdev->devpath,
1673 dev->driver_info->description);
1674
1675 net = dev->net;
1676 unregister_netdev(net);
1677
1678 cancel_work_sync(&dev->kevent);
1679
1680 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1681 dev_kfree_skb(urb->context);
1682 kfree(urb->sg);
1683 usb_free_urb(urb);
1684 }
1685
1686 if (dev->driver_info->unbind)
1687 dev->driver_info->unbind(dev, intf);
1688
1689 usb_kill_urb(dev->interrupt);
1690 usb_free_urb(dev->interrupt);
1691 kfree(dev->padding_pkt);
1692
1693 free_netdev(net);
1694 }
1695 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1696
1697 static const struct net_device_ops usbnet_netdev_ops = {
1698 .ndo_open = usbnet_open,
1699 .ndo_stop = usbnet_stop,
1700 .ndo_start_xmit = usbnet_start_xmit,
1701 .ndo_tx_timeout = usbnet_tx_timeout,
1702 .ndo_set_rx_mode = usbnet_set_rx_mode,
1703 .ndo_change_mtu = usbnet_change_mtu,
1704 .ndo_set_mac_address = eth_mac_addr,
1705 .ndo_validate_addr = eth_validate_addr,
1706 };
1707
1708 /*-------------------------------------------------------------------------*/
1709
1710 // precondition: never called in_interrupt
1711
1712 static const struct device_type wlan_type = {
1713 .name = "wlan",
1714 };
1715
1716 static const struct device_type wwan_type = {
1717 .name = "wwan",
1718 };
1719
1720 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1721 usbnet_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1722 {
1723 struct usbnet *dev;
1724 struct net_device *net;
1725 struct usb_host_interface *interface;
1726 const struct driver_info *info;
1727 struct usb_device *xdev;
1728 int status;
1729 const char *name;
1730 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1731
1732 /* usbnet already took usb runtime pm, so have to enable the feature
1733 * for usb interface, otherwise usb_autopm_get_interface may return
1734 * failure if RUNTIME_PM is enabled.
1735 */
1736 if (!driver->supports_autosuspend) {
1737 driver->supports_autosuspend = 1;
1738 pm_runtime_enable(&udev->dev);
1739 }
1740
1741 name = udev->dev.driver->name;
1742 info = (const struct driver_info *) prod->driver_info;
1743 if (!info) {
1744 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1745 return -ENODEV;
1746 }
1747 xdev = interface_to_usbdev(udev);
1748 interface = udev->cur_altsetting;
1749
1750 status = -ENOMEM;
1751
1752 // set up our own records
1753 net = alloc_etherdev(sizeof(*dev));
1754 if (!net)
1755 goto out;
1756
1757 /* netdev_printk() needs this so do it as early as possible */
1758 SET_NETDEV_DEV(net, &udev->dev);
1759
1760 dev = netdev_priv(net);
1761 dev->udev = xdev;
1762 dev->intf = udev;
1763 dev->driver_info = info;
1764 dev->driver_name = name;
1765 dev->rx_speed = SPEED_UNSET;
1766 dev->tx_speed = SPEED_UNSET;
1767
1768 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1769 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1770 init_waitqueue_head(&dev->wait);
1771 skb_queue_head_init (&dev->rxq);
1772 skb_queue_head_init (&dev->txq);
1773 skb_queue_head_init (&dev->done);
1774 skb_queue_head_init(&dev->rxq_pause);
1775 spin_lock_init(&dev->bql_spinlock);
1776 INIT_WORK(&dev->bh_work, usbnet_bh_work);
1777 INIT_WORK(&dev->kevent, usbnet_deferred_kevent);
1778 init_usb_anchor(&dev->deferred);
1779 timer_setup(&dev->delay, usbnet_bh, 0);
1780 mutex_init(&dev->phy_mutex);
1781 mutex_init(&dev->interrupt_mutex);
1782 dev->interrupt_count = 0;
1783
1784 dev->net = net;
1785 strscpy(net->name, "usb%d", sizeof(net->name));
1786
1787 /* rx and tx sides can use different message sizes;
1788 * bind() should set rx_urb_size in that case.
1789 */
1790 dev->hard_mtu = net->mtu + net->hard_header_len;
1791 net->min_mtu = 0;
1792 net->max_mtu = ETH_MAX_MTU;
1793
1794 net->netdev_ops = &usbnet_netdev_ops;
1795 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1796 net->ethtool_ops = &usbnet_ethtool_ops;
1797 net->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1798
1799 // allow device-specific bind/init procedures
1800 // NOTE net->name still not usable ...
1801 if (info->bind) {
1802 status = info->bind(dev, udev);
1803 if (status < 0)
1804 goto out1;
1805
1806 /* heuristic: rename to "eth%d" if we are not sure this link
1807 * is two-host (these links keep "usb%d")
1808 */
1809 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1810 !usbnet_needs_usb_name_format(dev, net))
1811 strscpy(net->name, "eth%d", sizeof(net->name));
1812 /* WLAN devices should always be named "wlan%d" */
1813 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1814 strscpy(net->name, "wlan%d", sizeof(net->name));
1815 /* WWAN devices should always be named "wwan%d" */
1816 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1817 strscpy(net->name, "wwan%d", sizeof(net->name));
1818
1819 /* devices that cannot do ARP */
1820 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1821 net->flags |= IFF_NOARP;
1822
1823 /* maybe the remote can't receive an Ethernet MTU */
1824 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1825 net->mtu = dev->hard_mtu - net->hard_header_len;
1826 } else if (!info->in || !info->out)
1827 status = usbnet_get_endpoints(dev, udev);
1828 else {
1829 u8 ep_addrs[3] = {
1830 info->in + USB_DIR_IN, info->out + USB_DIR_OUT, 0
1831 };
1832
1833 dev->in = usb_rcvbulkpipe(xdev, info->in);
1834 dev->out = usb_sndbulkpipe(xdev, info->out);
1835 if (!(info->flags & FLAG_NO_SETINT))
1836 status = usb_set_interface(xdev,
1837 interface->desc.bInterfaceNumber,
1838 interface->desc.bAlternateSetting);
1839 else
1840 status = 0;
1841
1842 if (status == 0 && !usb_check_bulk_endpoints(udev, ep_addrs))
1843 status = -EINVAL;
1844 }
1845 if (status >= 0 && dev->status)
1846 status = init_status(dev, udev);
1847 if (status < 0)
1848 goto out3;
1849
1850 if (!dev->rx_urb_size)
1851 dev->rx_urb_size = dev->hard_mtu;
1852 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1853 if (dev->maxpacket == 0) {
1854 /* that is a broken device */
1855 status = -ENODEV;
1856 goto out4;
1857 }
1858
1859 /* this flags the device for user space */
1860 if (!is_valid_ether_addr(net->dev_addr))
1861 eth_hw_addr_random(net);
1862
1863 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1864 SET_NETDEV_DEVTYPE(net, &wlan_type);
1865 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1866 SET_NETDEV_DEVTYPE(net, &wwan_type);
1867
1868 /* initialize max rx_qlen and tx_qlen */
1869 usbnet_update_max_qlen(dev);
1870
1871 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1872 !(info->flags & FLAG_MULTI_PACKET)) {
1873 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1874 if (!dev->padding_pkt) {
1875 status = -ENOMEM;
1876 goto out4;
1877 }
1878 }
1879
1880 status = register_netdev(net);
1881 if (status)
1882 goto out5;
1883 netif_info(dev, probe, dev->net,
1884 "register '%s' at usb-%s-%s, %s, %pM\n",
1885 udev->dev.driver->name,
1886 xdev->bus->bus_name, xdev->devpath,
1887 dev->driver_info->description,
1888 net->dev_addr);
1889
1890 // ok, it's ready to go.
1891 usb_set_intfdata(udev, dev);
1892
1893 netif_device_attach(net);
1894
1895 if (dev->driver_info->flags & FLAG_LINK_INTR)
1896 usbnet_link_change(dev, 0, 0);
1897
1898 return 0;
1899
1900 out5:
1901 kfree(dev->padding_pkt);
1902 out4:
1903 usb_free_urb(dev->interrupt);
1904 out3:
1905 if (info->unbind)
1906 info->unbind(dev, udev);
1907 out1:
1908 /* subdrivers must undo all they did in bind() if they
1909 * fail it, but we may fail later and a deferred kevent
1910 * may trigger an error resubmitting itself and, worse,
1911 * schedule a timer. So we kill it all just in case.
1912 */
1913 usbnet_mark_going_away(dev);
1914 cancel_work_sync(&dev->kevent);
1915 timer_delete_sync(&dev->delay);
1916 free_netdev(net);
1917 out:
1918 return status;
1919 }
1920 EXPORT_SYMBOL_GPL(usbnet_probe);
1921
1922 /*-------------------------------------------------------------------------*/
1923
1924 /*
1925 * suspend the whole driver as soon as the first interface is suspended
1926 * resume only when the last interface is resumed
1927 */
1928
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1929 int usbnet_suspend(struct usb_interface *intf, pm_message_t message)
1930 {
1931 struct usbnet *dev = usb_get_intfdata(intf);
1932
1933 if (!dev->suspend_count++) {
1934 spin_lock_irq(&dev->txq.lock);
1935 /* don't autosuspend while transmitting */
1936 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1937 dev->suspend_count--;
1938 spin_unlock_irq(&dev->txq.lock);
1939 return -EBUSY;
1940 } else {
1941 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1942 spin_unlock_irq(&dev->txq.lock);
1943 }
1944 /*
1945 * accelerate emptying of the rx and queues, to avoid
1946 * having everything error out.
1947 */
1948 netif_device_detach(dev->net);
1949 usbnet_terminate_urbs(dev);
1950 __usbnet_status_stop_force(dev);
1951
1952 /*
1953 * reattach so runtime management can use and
1954 * wake the device
1955 */
1956 netif_device_attach(dev->net);
1957 }
1958 return 0;
1959 }
1960 EXPORT_SYMBOL_GPL(usbnet_suspend);
1961
usbnet_resume(struct usb_interface * intf)1962 int usbnet_resume(struct usb_interface *intf)
1963 {
1964 struct usbnet *dev = usb_get_intfdata(intf);
1965 struct sk_buff *skb;
1966 struct urb *res;
1967 int retval;
1968
1969 if (!--dev->suspend_count) {
1970 /* resume interrupt URB if it was previously submitted */
1971 __usbnet_status_start_force(dev, GFP_NOIO);
1972
1973 spin_lock_irq(&dev->txq.lock);
1974 while ((res = usb_get_from_anchor(&dev->deferred))) {
1975
1976 skb = (struct sk_buff *)res->context;
1977 retval = usb_submit_urb(res, GFP_ATOMIC);
1978 if (retval < 0) {
1979 dev_kfree_skb_any(skb);
1980 kfree(res->sg);
1981 usb_free_urb(res);
1982 usb_autopm_put_interface_async(dev->intf);
1983 } else {
1984 netif_trans_update(dev->net);
1985 __skb_queue_tail(&dev->txq, skb);
1986 }
1987 }
1988
1989 smp_mb();
1990 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1991 spin_unlock_irq(&dev->txq.lock);
1992
1993 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1994 /* handle remote wakeup ASAP
1995 * we cannot race against stop
1996 */
1997 if (netif_device_present(dev->net) &&
1998 !timer_pending(&dev->delay) &&
1999 !test_bit(EVENT_RX_HALT, &dev->flags))
2000 rx_alloc_submit(dev, GFP_NOIO);
2001
2002 if (!(dev->txq.qlen >= TX_QLEN(dev)))
2003 netif_tx_wake_all_queues(dev->net);
2004 queue_work(system_bh_wq, &dev->bh_work);
2005 }
2006 }
2007
2008 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
2009 usb_autopm_get_interface_no_resume(intf);
2010
2011 return 0;
2012 }
2013 EXPORT_SYMBOL_GPL(usbnet_resume);
2014
2015 /*
2016 * Either a subdriver implements manage_power, then it is assumed to always
2017 * be ready to be suspended or it reports the readiness to be suspended
2018 * explicitly
2019 */
usbnet_device_suggests_idle(struct usbnet * dev)2020 void usbnet_device_suggests_idle(struct usbnet *dev)
2021 {
2022 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
2023 dev->intf->needs_remote_wakeup = 1;
2024 usb_autopm_put_interface_async(dev->intf);
2025 }
2026 }
2027 EXPORT_SYMBOL(usbnet_device_suggests_idle);
2028
2029 /*
2030 * For devices that can do without special commands
2031 */
usbnet_manage_power(struct usbnet * dev,int on)2032 int usbnet_manage_power(struct usbnet *dev, int on)
2033 {
2034 dev->intf->needs_remote_wakeup = on;
2035 return 0;
2036 }
2037 EXPORT_SYMBOL(usbnet_manage_power);
2038
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)2039 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
2040 {
2041 /* update link after link is reseted */
2042 if (link && !need_reset) {
2043 set_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2044 } else {
2045 clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2046 netif_carrier_off(dev->net);
2047 }
2048
2049 if (need_reset && link)
2050 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
2051 else
2052 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
2053 }
2054 EXPORT_SYMBOL(usbnet_link_change);
2055
2056 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2057 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2058 u16 value, u16 index, void *data, u16 size)
2059 {
2060 void *buf = NULL;
2061 int err = -ENOMEM;
2062
2063 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2064 " value=0x%04x index=0x%04x size=%d\n",
2065 cmd, reqtype, value, index, size);
2066
2067 if (size) {
2068 buf = kmalloc(size, GFP_NOIO);
2069 if (!buf)
2070 goto out;
2071 }
2072
2073 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2074 cmd, reqtype, value, index, buf, size,
2075 USB_CTRL_GET_TIMEOUT);
2076 if (err > 0 && err <= size) {
2077 if (data)
2078 memcpy(data, buf, err);
2079 else
2080 netdev_dbg(dev->net,
2081 "Huh? Data requested but thrown away.\n");
2082 }
2083 kfree(buf);
2084 out:
2085 return err;
2086 }
2087
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2088 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2089 u16 value, u16 index, const void *data,
2090 u16 size)
2091 {
2092 void *buf = NULL;
2093 int err = -ENOMEM;
2094
2095 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2096 " value=0x%04x index=0x%04x size=%d\n",
2097 cmd, reqtype, value, index, size);
2098
2099 if (data) {
2100 buf = kmemdup(data, size, GFP_NOIO);
2101 if (!buf)
2102 goto out;
2103 } else {
2104 if (size) {
2105 WARN_ON_ONCE(1);
2106 err = -EINVAL;
2107 goto out;
2108 }
2109 }
2110
2111 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2112 cmd, reqtype, value, index, buf, size,
2113 USB_CTRL_SET_TIMEOUT);
2114 kfree(buf);
2115
2116 out:
2117 return err;
2118 }
2119
2120 /*
2121 * The function can't be called inside suspend/resume callback,
2122 * otherwise deadlock will be caused.
2123 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2124 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2125 u16 value, u16 index, void *data, u16 size)
2126 {
2127 int ret;
2128
2129 if (usb_autopm_get_interface(dev->intf) < 0)
2130 return -ENODEV;
2131 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2132 data, size);
2133 usb_autopm_put_interface(dev->intf);
2134 return ret;
2135 }
2136 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2137
2138 /*
2139 * The function can't be called inside suspend/resume callback,
2140 * otherwise deadlock will be caused.
2141 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2142 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2143 u16 value, u16 index, const void *data, u16 size)
2144 {
2145 int ret;
2146
2147 if (usb_autopm_get_interface(dev->intf) < 0)
2148 return -ENODEV;
2149 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2150 data, size);
2151 usb_autopm_put_interface(dev->intf);
2152 return ret;
2153 }
2154 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2155
2156 /*
2157 * The function can be called inside suspend/resume callback safely
2158 * and should only be called by suspend/resume callback generally.
2159 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2160 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2161 u16 value, u16 index, void *data, u16 size)
2162 {
2163 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2164 data, size);
2165 }
2166 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2167
2168 /*
2169 * The function can be called inside suspend/resume callback safely
2170 * and should only be called by suspend/resume callback generally.
2171 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2172 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2173 u16 value, u16 index, const void *data,
2174 u16 size)
2175 {
2176 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2177 data, size);
2178 }
2179 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2180
usbnet_async_cmd_cb(struct urb * urb)2181 static void usbnet_async_cmd_cb(struct urb *urb)
2182 {
2183 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2184 int status = urb->status;
2185
2186 if (status < 0)
2187 dev_dbg(&urb->dev->dev, "%s failed with %d",
2188 __func__, status);
2189
2190 kfree(req);
2191 usb_free_urb(urb);
2192 }
2193
2194 /*
2195 * The caller must make sure that device can't be put into suspend
2196 * state until the control URB completes.
2197 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2198 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2199 u16 value, u16 index, const void *data, u16 size)
2200 {
2201 struct usb_ctrlrequest *req;
2202 struct urb *urb;
2203 int err = -ENOMEM;
2204 void *buf = NULL;
2205
2206 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2207 " value=0x%04x index=0x%04x size=%d\n",
2208 cmd, reqtype, value, index, size);
2209
2210 urb = usb_alloc_urb(0, GFP_ATOMIC);
2211 if (!urb)
2212 goto fail;
2213
2214 if (data) {
2215 buf = kmemdup(data, size, GFP_ATOMIC);
2216 if (!buf) {
2217 netdev_err(dev->net, "Error allocating buffer"
2218 " in %s!\n", __func__);
2219 goto fail_free_urb;
2220 }
2221 }
2222
2223 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2224 if (!req)
2225 goto fail_free_buf;
2226
2227 req->bRequestType = reqtype;
2228 req->bRequest = cmd;
2229 req->wValue = cpu_to_le16(value);
2230 req->wIndex = cpu_to_le16(index);
2231 req->wLength = cpu_to_le16(size);
2232
2233 usb_fill_control_urb(urb, dev->udev,
2234 usb_sndctrlpipe(dev->udev, 0),
2235 (void *)req, buf, size,
2236 usbnet_async_cmd_cb, req);
2237 urb->transfer_flags |= URB_FREE_BUFFER;
2238
2239 err = usb_submit_urb(urb, GFP_ATOMIC);
2240 if (err < 0) {
2241 netdev_err(dev->net, "Error submitting the control"
2242 " message: status=%d\n", err);
2243 goto fail_free_all;
2244 }
2245 return 0;
2246
2247 fail_free_all:
2248 kfree(req);
2249 fail_free_buf:
2250 kfree(buf);
2251 /*
2252 * avoid a double free
2253 * needed because the flag can be set only
2254 * after filling the URB
2255 */
2256 urb->transfer_flags = 0;
2257 fail_free_urb:
2258 usb_free_urb(urb);
2259 fail:
2260 return err;
2261
2262 }
2263 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2264 /*-------------------------------------------------------------------------*/
2265
usbnet_init(void)2266 static int __init usbnet_init(void)
2267 {
2268 /* Compiler should optimize this out. */
2269 BUILD_BUG_ON(
2270 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2271
2272 return 0;
2273 }
2274 module_init(usbnet_init);
2275
usbnet_exit(void)2276 static void __exit usbnet_exit(void)
2277 {
2278 }
2279 module_exit(usbnet_exit);
2280
2281 MODULE_AUTHOR("David Brownell");
2282 MODULE_DESCRIPTION("USB network driver framework");
2283 MODULE_LICENSE("GPL");
2284