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