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/hex.h>
22 #include <linux/init.h>
23 #include <linux/netdevice.h>
24 #include <linux/etherdevice.h>
25 #include <linux/ctype.h>
26 #include <linux/ethtool.h>
27 #include <linux/workqueue.h>
28 #include <linux/mii.h>
29 #include <linux/usb.h>
30 #include <linux/usb/usbnet.h>
31 #include <linux/slab.h>
32 #include <linux/kernel.h>
33 #include <linux/pm_runtime.h>
34
35 /*-------------------------------------------------------------------------*/
36
37 /*
38 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
39 * Several dozen bytes of IPv4 data can fit in two such transactions.
40 * One maximum size Ethernet packet takes twenty four of them.
41 * For high speed, each frame comfortably fits almost 36 max size
42 * Ethernet packets (so queues should be bigger).
43 *
44 * The goal is to let the USB host controller be busy for 5msec or
45 * more before an irq is required, under load. Jumbograms change
46 * the equation.
47 */
48 #define MAX_QUEUE_MEMORY (60 * 1518)
49 #define RX_QLEN(dev) ((dev)->rx_qlen)
50 #define TX_QLEN(dev) ((dev)->tx_qlen)
51
52 // reawaken network queue this soon after stopping; else watchdog barks
53 #define TX_TIMEOUT_JIFFIES (5*HZ)
54
55 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
56 * us (it polls at HZ/4 usually) before we report too many false errors.
57 */
58 #define THROTTLE_JIFFIES (HZ/8)
59
60 // between wakeups
61 #define UNLINK_TIMEOUT_MS 3
62
63 /*-------------------------------------------------------------------------*/
64
65 /* use ethtool to change the level for any given device */
66 static int msg_level = -1;
67 module_param (msg_level, int, 0);
68 MODULE_PARM_DESC (msg_level, "Override default message level");
69
70 /*-------------------------------------------------------------------------*/
71
72 static const char * const usbnet_event_names[] = {
73 [EVENT_TX_HALT] = "EVENT_TX_HALT",
74 [EVENT_RX_HALT] = "EVENT_RX_HALT",
75 [EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
76 [EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
77 [EVENT_LINK_RESET] = "EVENT_LINK_RESET",
78 [EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
79 [EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
80 [EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
81 [EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
82 [EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
83 [EVENT_RX_KILL] = "EVENT_RX_KILL",
84 [EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
85 [EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
86 [EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
87 };
88
89 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)90 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
91 {
92 int tmp;
93 struct usb_host_interface *alt = NULL;
94 struct usb_host_endpoint *in = NULL, *out = NULL;
95 struct usb_host_endpoint *status = NULL;
96
97 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
98 unsigned ep;
99
100 in = out = status = NULL;
101 alt = intf->altsetting + tmp;
102
103 /* take the first altsetting with in-bulk + out-bulk;
104 * remember any status endpoint, just in case;
105 * ignore other endpoints and altsettings.
106 */
107 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
108 struct usb_host_endpoint *e;
109 int intr = 0;
110
111 e = alt->endpoint + ep;
112
113 /* ignore endpoints which cannot transfer data */
114 if (!usb_endpoint_maxp(&e->desc))
115 continue;
116
117 switch (e->desc.bmAttributes) {
118 case USB_ENDPOINT_XFER_INT:
119 if (!usb_endpoint_dir_in(&e->desc))
120 continue;
121 intr = 1;
122 fallthrough;
123 case USB_ENDPOINT_XFER_BULK:
124 break;
125 default:
126 continue;
127 }
128 if (usb_endpoint_dir_in(&e->desc)) {
129 if (!intr && !in)
130 in = e;
131 else if (intr && !status)
132 status = e;
133 } else {
134 if (!out)
135 out = e;
136 }
137 }
138 if (in && out)
139 break;
140 }
141 if (!alt || !in || !out)
142 return -EINVAL;
143
144 if (alt->desc.bAlternateSetting != 0 ||
145 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
146 tmp = usb_set_interface(dev->udev, alt->desc.bInterfaceNumber,
147 alt->desc.bAlternateSetting);
148 if (tmp < 0)
149 return tmp;
150 }
151
152 dev->in = usb_rcvbulkpipe(dev->udev,
153 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
154 dev->out = usb_sndbulkpipe(dev->udev,
155 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
156 dev->status = status;
157 return 0;
158 }
159 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
160
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)161 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
162 {
163 u8 addr[ETH_ALEN];
164 int tmp = -1, ret;
165 unsigned char buf [13];
166
167 ret = usb_string(dev->udev, iMACAddress, buf, sizeof(buf));
168 if (ret == 12)
169 tmp = hex2bin(addr, buf, 6);
170 if (tmp < 0) {
171 dev_dbg(&dev->udev->dev,
172 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
173 if (ret >= 0)
174 ret = -EINVAL;
175 return ret;
176 }
177 eth_hw_addr_set(dev->net, addr);
178 return 0;
179 }
180 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
181
usbnet_needs_usb_name_format(struct usbnet * dev,struct net_device * net)182 static bool usbnet_needs_usb_name_format(struct usbnet *dev, struct net_device *net)
183 {
184 /* Point to point devices which don't have a real MAC address
185 * (or report a fake local one) have historically used the usb%d
186 * naming. Preserve this..
187 */
188 return (dev->driver_info->flags & FLAG_POINTTOPOINT) != 0 &&
189 (is_zero_ether_addr(net->dev_addr) ||
190 is_local_ether_addr(net->dev_addr));
191 }
192
intr_complete(struct urb * urb)193 static void intr_complete(struct urb *urb)
194 {
195 struct usbnet *dev = urb->context;
196 int status = urb->status;
197
198 switch (status) {
199 /* success */
200 case 0:
201 dev->driver_info->status(dev, urb);
202 break;
203
204 /* software-driven interface shutdown */
205 case -ENOENT: /* urb killed */
206 case -ESHUTDOWN: /* hardware gone */
207 netif_dbg(dev, ifdown, dev->net,
208 "intr shutdown, code %d\n", status);
209 return;
210
211 /* NOTE: not throttling like RX/TX, since this endpoint
212 * already polls infrequently
213 */
214 default:
215 netdev_dbg(dev->net, "intr status %d\n", status);
216 break;
217 }
218
219 status = usb_submit_urb(urb, GFP_ATOMIC);
220 if (status != 0)
221 netif_err(dev, timer, dev->net,
222 "intr resubmit --> %d\n", status);
223 }
224
init_status(struct usbnet * dev,struct usb_interface * intf)225 static int init_status(struct usbnet *dev, struct usb_interface *intf)
226 {
227 char *buf = NULL;
228 unsigned pipe = 0;
229 unsigned maxp;
230 unsigned period;
231
232 if (!dev->driver_info->status)
233 return 0;
234
235 pipe = usb_rcvintpipe(dev->udev,
236 dev->status->desc.bEndpointAddress
237 & USB_ENDPOINT_NUMBER_MASK);
238 maxp = usb_maxpacket(dev->udev, pipe);
239
240 /* avoid 1 msec chatter: min 8 msec poll rate */
241 period = max ((int) dev->status->desc.bInterval,
242 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
243
244 buf = kmalloc(maxp, GFP_KERNEL);
245 if (buf) {
246 dev->interrupt = usb_alloc_urb(0, GFP_KERNEL);
247 if (!dev->interrupt) {
248 kfree(buf);
249 return -ENOMEM;
250 } else {
251 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
252 buf, maxp, intr_complete, dev, period);
253 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
254 dev_dbg(&intf->dev,
255 "status ep%din, %d bytes period %d\n",
256 usb_pipeendpoint(pipe), maxp, period);
257 }
258 }
259 return 0;
260 }
261
262 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)263 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
264 {
265 int ret = 0;
266
267 WARN_ON_ONCE(dev->interrupt == NULL);
268 if (dev->interrupt) {
269 mutex_lock(&dev->interrupt_mutex);
270
271 if (++dev->interrupt_count == 1)
272 ret = usb_submit_urb(dev->interrupt, mem_flags);
273
274 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
275 dev->interrupt_count);
276 mutex_unlock(&dev->interrupt_mutex);
277 }
278 return ret;
279 }
280 EXPORT_SYMBOL_GPL(usbnet_status_start);
281
282 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)283 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
284 {
285 int ret = 0;
286
287 mutex_lock(&dev->interrupt_mutex);
288 if (dev->interrupt_count) {
289 ret = usb_submit_urb(dev->interrupt, mem_flags);
290 dev_dbg(&dev->udev->dev,
291 "submitted interrupt URB for resume\n");
292 }
293 mutex_unlock(&dev->interrupt_mutex);
294 return ret;
295 }
296
297 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)298 void usbnet_status_stop(struct usbnet *dev)
299 {
300 if (dev->interrupt) {
301 mutex_lock(&dev->interrupt_mutex);
302 WARN_ON(dev->interrupt_count == 0);
303
304 if (dev->interrupt_count && --dev->interrupt_count == 0)
305 usb_kill_urb(dev->interrupt);
306
307 dev_dbg(&dev->udev->dev,
308 "decremented interrupt URB count to %d\n",
309 dev->interrupt_count);
310 mutex_unlock(&dev->interrupt_mutex);
311 }
312 }
313 EXPORT_SYMBOL_GPL(usbnet_status_stop);
314
315 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)316 static void __usbnet_status_stop_force(struct usbnet *dev)
317 {
318 if (dev->interrupt) {
319 mutex_lock(&dev->interrupt_mutex);
320 usb_kill_urb(dev->interrupt);
321 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
322 mutex_unlock(&dev->interrupt_mutex);
323 }
324 }
325
326 /* Passes this packet up the stack, updating its accounting.
327 * Some link protocols batch packets, so their rx_fixup paths
328 * can return clones as well as just modify the original skb.
329 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)330 void usbnet_skb_return(struct usbnet *dev, struct sk_buff *skb)
331 {
332 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
333 unsigned long flags;
334 int status;
335
336 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
337 skb_queue_tail(&dev->rxq_pause, skb);
338 return;
339 }
340
341 /* only update if unset to allow minidriver rx_fixup override */
342 if (skb->protocol == 0)
343 skb->protocol = eth_type_trans(skb, dev->net);
344
345 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
346 u64_stats_inc(&stats64->rx_packets);
347 u64_stats_add(&stats64->rx_bytes, skb->len);
348 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
349
350 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
351 skb->len + sizeof(struct ethhdr), skb->protocol);
352 memset(skb->cb, 0, sizeof(struct skb_data));
353
354 if (skb_defer_rx_timestamp(skb))
355 return;
356
357 status = netif_rx (skb);
358 if (status != NET_RX_SUCCESS)
359 netif_dbg(dev, rx_err, dev->net,
360 "netif_rx status %d\n", status);
361 }
362 EXPORT_SYMBOL_GPL(usbnet_skb_return);
363
364 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)365 void usbnet_update_max_qlen(struct usbnet *dev)
366 {
367 enum usb_device_speed speed = dev->udev->speed;
368
369 if (!dev->rx_urb_size || !dev->hard_mtu)
370 goto insanity;
371 switch (speed) {
372 case USB_SPEED_HIGH:
373 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
374 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
375 break;
376 case USB_SPEED_SUPER:
377 case USB_SPEED_SUPER_PLUS:
378 /*
379 * Not take default 5ms qlen for super speed HC to
380 * save memory, and iperf tests show 2.5ms qlen can
381 * work well
382 */
383 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
384 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
385 break;
386 default:
387 insanity:
388 dev->rx_qlen = dev->tx_qlen = 4;
389 }
390 }
391 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
392
393
394 /*-------------------------------------------------------------------------
395 *
396 * Network Device Driver (peer link to "Host Device", from USB host)
397 *
398 *-------------------------------------------------------------------------*/
399
usbnet_change_mtu(struct net_device * net,int new_mtu)400 int usbnet_change_mtu(struct net_device *net, int new_mtu)
401 {
402 struct usbnet *dev = netdev_priv(net);
403 int ll_mtu = new_mtu + net->hard_header_len;
404 int old_hard_mtu = dev->hard_mtu;
405 int old_rx_urb_size = dev->rx_urb_size;
406
407 // no second zero-length packet read wanted after mtu-sized packets
408 if ((ll_mtu % dev->maxpacket) == 0)
409 return -EDOM;
410 WRITE_ONCE(net->mtu, new_mtu);
411
412 dev->hard_mtu = net->mtu + net->hard_header_len;
413 if (dev->rx_urb_size == old_hard_mtu) {
414 dev->rx_urb_size = dev->hard_mtu;
415 if (dev->rx_urb_size > old_rx_urb_size) {
416 usbnet_pause_rx(dev);
417 usbnet_unlink_rx_urbs(dev);
418 usbnet_resume_rx(dev);
419 }
420 }
421
422 /* max qlen depend on hard_mtu and rx_urb_size */
423 usbnet_update_max_qlen(dev);
424
425 return 0;
426 }
427 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
428
429 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)430 static void __usbnet_queue_skb(struct sk_buff_head *list,
431 struct sk_buff *newsk, enum skb_state state)
432 {
433 struct skb_data *entry = (struct skb_data *) newsk->cb;
434
435 __skb_queue_tail(list, newsk);
436 entry->state = state;
437 }
438
439 /*-------------------------------------------------------------------------*/
440
441 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
442 * completion callbacks. 2.5 should have fixed those bugs...
443 */
444
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)445 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
446 struct sk_buff_head *list, enum skb_state state)
447 {
448 unsigned long flags;
449 enum skb_state old_state;
450 struct skb_data *entry = (struct skb_data *) skb->cb;
451
452 spin_lock_irqsave(&list->lock, flags);
453 old_state = entry->state;
454 entry->state = state;
455 __skb_unlink(skb, list);
456
457 /* defer_bh() is never called with list == &dev->done.
458 * spin_lock_nested() tells lockdep that it is OK to take
459 * dev->done.lock here with list->lock held.
460 */
461 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
462
463 __skb_queue_tail(&dev->done, skb);
464 if (dev->done.qlen == 1)
465 queue_work(system_bh_wq, &dev->bh_work);
466 spin_unlock(&dev->done.lock);
467 spin_unlock_irqrestore(&list->lock, flags);
468 return old_state;
469 }
470
471 /* some work can't be done in tasklets, so we use keventd
472 *
473 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
474 * but tasklet_schedule() doesn't. hope the failure is rare.
475 */
usbnet_defer_kevent(struct usbnet * dev,int work)476 void usbnet_defer_kevent(struct usbnet *dev, int work)
477 {
478 set_bit (work, &dev->flags);
479 if (!usbnet_going_away(dev)) {
480 if (!schedule_work(&dev->kevent))
481 netdev_dbg(dev->net,
482 "kevent %s may have been dropped\n",
483 usbnet_event_names[work]);
484 else
485 netdev_dbg(dev->net,
486 "kevent %s scheduled\n", usbnet_event_names[work]);
487 }
488 }
489 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
490
491 /*-------------------------------------------------------------------------*/
492
493 static void rx_complete(struct urb *urb);
494
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)495 static int rx_submit(struct usbnet *dev, struct urb *urb, gfp_t flags)
496 {
497 struct sk_buff *skb;
498 struct skb_data *entry;
499 int retval = 0;
500 unsigned long lockflags;
501 size_t size = dev->rx_urb_size;
502
503 /* prevent rx skb allocation when error ratio is high */
504 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
505 usb_free_urb(urb);
506 return -ENOLINK;
507 }
508
509 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
510 skb = __netdev_alloc_skb(dev->net, size, flags);
511 else
512 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
513 if (!skb) {
514 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
515 usbnet_defer_kevent(dev, EVENT_RX_MEMORY);
516 usb_free_urb(urb);
517 return -ENOMEM;
518 }
519
520 entry = (struct skb_data *) skb->cb;
521 entry->urb = urb;
522 entry->dev = dev;
523 entry->length = 0;
524
525 usb_fill_bulk_urb(urb, dev->udev, dev->in,
526 skb->data, size, rx_complete, skb);
527
528 spin_lock_irqsave(&dev->rxq.lock, lockflags);
529
530 if (netif_running(dev->net) &&
531 netif_device_present(dev->net) &&
532 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
533 !test_bit(EVENT_RX_HALT, &dev->flags) &&
534 !test_bit(EVENT_DEV_ASLEEP, &dev->flags) &&
535 !usbnet_going_away(dev)) {
536 switch (retval = usb_submit_urb(urb, GFP_ATOMIC)) {
537 case -EPIPE:
538 usbnet_defer_kevent(dev, EVENT_RX_HALT);
539 break;
540 case -ENOMEM:
541 usbnet_defer_kevent(dev, EVENT_RX_MEMORY);
542 break;
543 case -ENODEV:
544 netif_dbg(dev, ifdown, dev->net, "device gone\n");
545 netif_device_detach(dev->net);
546 break;
547 case -EHOSTUNREACH:
548 retval = -ENOLINK;
549 break;
550 default:
551 netif_dbg(dev, rx_err, dev->net,
552 "rx submit, %d\n", retval);
553 queue_work(system_bh_wq, &dev->bh_work);
554 break;
555 case 0:
556 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
557 }
558 } else {
559 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
560 retval = -ENOLINK;
561 }
562 spin_unlock_irqrestore(&dev->rxq.lock, lockflags);
563 if (retval) {
564 dev_kfree_skb_any(skb);
565 usb_free_urb(urb);
566 }
567 return retval;
568 }
569
570
571 /*-------------------------------------------------------------------------*/
572
rx_process(struct usbnet * dev,struct sk_buff * skb)573 static inline int rx_process(struct usbnet *dev, struct sk_buff *skb)
574 {
575 if (dev->driver_info->rx_fixup &&
576 !dev->driver_info->rx_fixup(dev, skb)) {
577 /* With RX_ASSEMBLE, rx_fixup() must update counters */
578 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
579 dev->net->stats.rx_errors++;
580 return -EPROTO;
581 }
582 // else network stack removes extra byte if we forced a short packet
583
584 /* all data was already cloned from skb inside the driver */
585 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
586 return -EALREADY;
587
588 if (skb->len < ETH_HLEN) {
589 dev->net->stats.rx_errors++;
590 dev->net->stats.rx_length_errors++;
591 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
592 return -EPROTO;
593 }
594
595 usbnet_skb_return(dev, skb);
596 return 0;
597 }
598
599 /*-------------------------------------------------------------------------*/
600
rx_complete(struct urb * urb)601 static void rx_complete(struct urb *urb)
602 {
603 struct sk_buff *skb = (struct sk_buff *) urb->context;
604 struct skb_data *entry = (struct skb_data *) skb->cb;
605 struct usbnet *dev = entry->dev;
606 int urb_status = urb->status;
607 enum skb_state state;
608
609 skb_put(skb, urb->actual_length);
610 state = rx_done;
611 entry->urb = NULL;
612
613 switch (urb_status) {
614 /* success */
615 case 0:
616 break;
617
618 /* stalls need manual reset. this is rare ... except that
619 * when going through USB 2.0 TTs, unplug appears this way.
620 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
621 * storm, recovering as needed.
622 */
623 case -EPIPE:
624 dev->net->stats.rx_errors++;
625 usbnet_defer_kevent(dev, EVENT_RX_HALT);
626 fallthrough;
627
628 /* software-driven interface shutdown */
629 case -ECONNRESET: /* async unlink */
630 case -ESHUTDOWN: /* hardware gone */
631 netif_dbg(dev, ifdown, dev->net,
632 "rx shutdown, code %d\n", urb_status);
633 goto block;
634
635 /* we get controller i/o faults during hub_wq disconnect() delays.
636 * throttle down resubmits, to avoid log floods; just temporarily,
637 * so we still recover when the fault isn't a hub_wq delay.
638 */
639 case -EPROTO:
640 case -ETIME:
641 case -EILSEQ:
642 dev->net->stats.rx_errors++;
643 if (!timer_pending(&dev->delay)) {
644 mod_timer(&dev->delay, jiffies + THROTTLE_JIFFIES);
645 netif_dbg(dev, link, dev->net,
646 "rx throttle %d\n", urb_status);
647 }
648 block:
649 state = rx_cleanup;
650 entry->urb = urb;
651 urb = NULL;
652 break;
653
654 /* data overrun ... flush fifo? */
655 case -EOVERFLOW:
656 dev->net->stats.rx_over_errors++;
657 fallthrough;
658
659 default:
660 state = rx_cleanup;
661 dev->net->stats.rx_errors++;
662 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
663 break;
664 }
665
666 /* stop rx if packet error rate is high */
667 if (++dev->pkt_cnt > 30) {
668 dev->pkt_cnt = 0;
669 dev->pkt_err = 0;
670 } else {
671 if (state == rx_cleanup)
672 dev->pkt_err++;
673 if (dev->pkt_err > 20)
674 set_bit(EVENT_RX_KILL, &dev->flags);
675 }
676
677 state = defer_bh(dev, skb, &dev->rxq, state);
678
679 if (urb) {
680 if (netif_running(dev->net) &&
681 !test_bit(EVENT_RX_HALT, &dev->flags) &&
682 state != unlink_start) {
683 rx_submit(dev, urb, GFP_ATOMIC);
684 usb_mark_last_busy(dev->udev);
685 return;
686 }
687 usb_free_urb(urb);
688 }
689 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
690 }
691
692 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)693 void usbnet_pause_rx(struct usbnet *dev)
694 {
695 set_bit(EVENT_RX_PAUSED, &dev->flags);
696
697 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
698 }
699 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
700
usbnet_resume_rx(struct usbnet * dev)701 void usbnet_resume_rx(struct usbnet *dev)
702 {
703 struct sk_buff *skb;
704 int num = 0;
705
706 local_bh_disable();
707 clear_bit(EVENT_RX_PAUSED, &dev->flags);
708
709 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
710 usbnet_skb_return(dev, skb);
711 num++;
712 }
713
714 queue_work(system_bh_wq, &dev->bh_work);
715 local_bh_enable();
716
717 netif_dbg(dev, rx_status, dev->net,
718 "paused rx queue disabled, %d skbs requeued\n", num);
719 }
720 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
721
usbnet_purge_paused_rxq(struct usbnet * dev)722 void usbnet_purge_paused_rxq(struct usbnet *dev)
723 {
724 skb_queue_purge(&dev->rxq_pause);
725 }
726 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
727
728 /*-------------------------------------------------------------------------*/
729
730 // unlink pending rx/tx; completion handlers do all other cleanup
731
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)732 static int unlink_urbs(struct usbnet *dev, struct sk_buff_head *q)
733 {
734 unsigned long flags;
735 struct sk_buff *skb;
736 int count = 0;
737
738 spin_lock_irqsave (&q->lock, flags);
739 while (!skb_queue_empty(q)) {
740 struct skb_data *entry;
741 struct urb *urb;
742 int retval;
743
744 skb_queue_walk(q, skb) {
745 entry = (struct skb_data *) skb->cb;
746 if (entry->state != unlink_start)
747 goto found;
748 }
749 break;
750 found:
751 entry->state = unlink_start;
752 urb = entry->urb;
753
754 /*
755 * Get reference count of the URB to avoid it to be
756 * freed during usb_unlink_urb, which may trigger
757 * use-after-free problem inside usb_unlink_urb since
758 * usb_unlink_urb is always racing with .complete
759 * handler(include defer_bh).
760 */
761 usb_get_urb(urb);
762 spin_unlock_irqrestore(&q->lock, flags);
763 // during some PM-driven resume scenarios,
764 // these (async) unlinks complete immediately
765 retval = usb_unlink_urb(urb);
766 if (retval != -EINPROGRESS && retval != 0)
767 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
768 else
769 count++;
770 usb_put_urb(urb);
771 spin_lock_irqsave(&q->lock, flags);
772 }
773 spin_unlock_irqrestore(&q->lock, flags);
774 return count;
775 }
776
777 // Flush all pending rx urbs
778 // minidrivers may need to do this when the MTU changes
779
usbnet_unlink_rx_urbs(struct usbnet * dev)780 void usbnet_unlink_rx_urbs(struct usbnet *dev)
781 {
782 if (netif_running(dev->net)) {
783 (void) unlink_urbs (dev, &dev->rxq);
784 queue_work(system_bh_wq, &dev->bh_work);
785 }
786 }
787 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
788
789 /*-------------------------------------------------------------------------*/
790
wait_skb_queue_empty(struct sk_buff_head * q)791 static void wait_skb_queue_empty(struct sk_buff_head *q)
792 {
793 unsigned long flags;
794
795 spin_lock_irqsave(&q->lock, flags);
796 while (!skb_queue_empty(q)) {
797 spin_unlock_irqrestore(&q->lock, flags);
798 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
799 set_current_state(TASK_UNINTERRUPTIBLE);
800 spin_lock_irqsave(&q->lock, flags);
801 }
802 spin_unlock_irqrestore(&q->lock, flags);
803 }
804
805 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)806 static void usbnet_terminate_urbs(struct usbnet *dev)
807 {
808 DECLARE_WAITQUEUE(wait, current);
809 int temp;
810
811 /* ensure there are no more active urbs */
812 add_wait_queue(&dev->wait, &wait);
813 set_current_state(TASK_UNINTERRUPTIBLE);
814 temp = unlink_urbs(dev, &dev->txq) +
815 unlink_urbs(dev, &dev->rxq);
816
817 /* maybe wait for deletions to finish. */
818 wait_skb_queue_empty(&dev->rxq);
819 wait_skb_queue_empty(&dev->txq);
820 wait_skb_queue_empty(&dev->done);
821 netif_dbg(dev, ifdown, dev->net,
822 "waited for %d urb completions\n", temp);
823 set_current_state(TASK_RUNNING);
824 remove_wait_queue(&dev->wait, &wait);
825 }
826
usbnet_stop(struct net_device * net)827 int usbnet_stop(struct net_device *net)
828 {
829 struct usbnet *dev = netdev_priv(net);
830 const struct driver_info *info = dev->driver_info;
831 int retval, pm, mpn;
832
833 clear_bit(EVENT_DEV_OPEN, &dev->flags);
834 netif_stop_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 netdev_reset_queue(net);
879
880 if (!pm)
881 usb_autopm_put_interface(dev->intf);
882
883 if (info->manage_power && mpn)
884 info->manage_power(dev, 0);
885 else
886 usb_autopm_put_interface(dev->intf);
887
888 return 0;
889 }
890 EXPORT_SYMBOL_GPL(usbnet_stop);
891
892 /*-------------------------------------------------------------------------*/
893
894 // posts reads, and enables write queuing
895
896 // precondition: never called in_interrupt
897
usbnet_open(struct net_device * net)898 int usbnet_open(struct net_device *net)
899 {
900 struct usbnet *dev = netdev_priv(net);
901 int retval;
902 const struct driver_info *info = dev->driver_info;
903
904 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
905 netif_info(dev, ifup, dev->net,
906 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
907 retval,
908 dev->udev->bus->bus_name,
909 dev->udev->devpath,
910 info->description);
911 goto done_nopm;
912 }
913
914 // put into "known safe" state
915 if (info->reset) {
916 retval = info->reset(dev);
917 if (retval < 0) {
918 netif_info(dev, ifup, dev->net,
919 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
920 retval,
921 dev->udev->bus->bus_name,
922 dev->udev->devpath,
923 info->description);
924 goto done;
925 }
926 }
927
928 /* hard_mtu or rx_urb_size may change in reset() */
929 usbnet_update_max_qlen(dev);
930
931 // insist peer be connected
932 if (info->check_connect) {
933 retval = info->check_connect(dev);
934 if (retval < 0) {
935 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
936 goto done;
937 }
938 }
939
940 /* start any status interrupt transfer */
941 if (dev->interrupt) {
942 retval = usbnet_status_start(dev, GFP_KERNEL);
943 if (retval < 0) {
944 netif_err(dev, ifup, dev->net,
945 "intr submit %d\n", retval);
946 goto done;
947 }
948 }
949
950 set_bit(EVENT_DEV_OPEN, &dev->flags);
951 netdev_reset_queue(net);
952 netif_start_queue (net);
953 netif_info(dev, ifup, dev->net,
954 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
955 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
956 dev->net->mtu,
957 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
958 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
959 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
960 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
961 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
962 "simple");
963
964 /* reset rx error state */
965 dev->pkt_cnt = 0;
966 dev->pkt_err = 0;
967 clear_bit(EVENT_RX_KILL, &dev->flags);
968
969 // delay posting reads until we're fully open
970 queue_work(system_bh_wq, &dev->bh_work);
971 if (info->manage_power) {
972 retval = info->manage_power(dev, 1);
973 if (retval < 0) {
974 retval = 0;
975 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
976 } else {
977 usb_autopm_put_interface(dev->intf);
978 }
979 }
980 return retval;
981 done:
982 usb_autopm_put_interface(dev->intf);
983 done_nopm:
984 return retval;
985 }
986 EXPORT_SYMBOL_GPL(usbnet_open);
987
988 /*-------------------------------------------------------------------------*/
989
990 /* ethtool methods; minidrivers may need to add some more, but
991 * they'll probably want to use this base set.
992 */
993
994 /* These methods are written on the assumption that the device
995 * uses MII
996 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)997 int usbnet_get_link_ksettings_mii(struct net_device *net,
998 struct ethtool_link_ksettings *cmd)
999 {
1000 struct usbnet *dev = netdev_priv(net);
1001
1002 if (!dev->mii.mdio_read)
1003 return -EOPNOTSUPP;
1004
1005 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
1006
1007 return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
1010
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)1011 int usbnet_get_link_ksettings_internal(struct net_device *net,
1012 struct ethtool_link_ksettings *cmd)
1013 {
1014 struct usbnet *dev = netdev_priv(net);
1015
1016 /* the assumption that speed is equal on tx and rx
1017 * is deeply engrained into the networking layer.
1018 * For wireless stuff it is not true.
1019 * We assume that rx_speed matters more.
1020 */
1021 if (dev->rx_speed != SPEED_UNSET)
1022 cmd->base.speed = dev->rx_speed / 1000000;
1023 else if (dev->tx_speed != SPEED_UNSET)
1024 cmd->base.speed = dev->tx_speed / 1000000;
1025 else
1026 cmd->base.speed = SPEED_UNKNOWN;
1027
1028 /* The standard "Universal Serial Bus Class Definitions
1029 * for Communications Devices v1.2" does not specify
1030 * anything about duplex status.
1031 * So set it DUPLEX_UNKNOWN instead of default DUPLEX_HALF.
1032 */
1033 cmd->base.duplex = DUPLEX_UNKNOWN;
1034
1035 return 0;
1036 }
1037 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1038
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1039 int usbnet_set_link_ksettings_mii(struct net_device *net,
1040 const struct ethtool_link_ksettings *cmd)
1041 {
1042 struct usbnet *dev = netdev_priv(net);
1043 int retval;
1044
1045 if (!dev->mii.mdio_write)
1046 return -EOPNOTSUPP;
1047
1048 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1049
1050 /* link speed/duplex might have changed */
1051 if (dev->driver_info->link_reset)
1052 dev->driver_info->link_reset(dev);
1053
1054 /* hard_mtu or rx_urb_size may change in link_reset() */
1055 usbnet_update_max_qlen(dev);
1056
1057 return retval;
1058 }
1059 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1060
usbnet_get_link(struct net_device * net)1061 u32 usbnet_get_link(struct net_device *net)
1062 {
1063 struct usbnet *dev = netdev_priv(net);
1064
1065 /* If a check_connect is defined, return its result */
1066 if (dev->driver_info->check_connect)
1067 return dev->driver_info->check_connect(dev) == 0;
1068
1069 /* if the device has mii operations, use those */
1070 if (dev->mii.mdio_read)
1071 return mii_link_ok(&dev->mii);
1072
1073 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1074 return ethtool_op_get_link(net);
1075 }
1076 EXPORT_SYMBOL_GPL(usbnet_get_link);
1077
usbnet_nway_reset(struct net_device * net)1078 int usbnet_nway_reset(struct net_device *net)
1079 {
1080 struct usbnet *dev = netdev_priv(net);
1081
1082 if (!dev->mii.mdio_write)
1083 return -EOPNOTSUPP;
1084
1085 return mii_nway_restart(&dev->mii);
1086 }
1087 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1088
usbnet_mii_ioctl(struct net_device * net,struct ifreq * rq,int cmd)1089 int usbnet_mii_ioctl(struct net_device *net, struct ifreq *rq, int cmd)
1090 {
1091 struct usbnet *dev = netdev_priv(net);
1092
1093 return generic_mii_ioctl(&dev->mii, if_mii(rq), cmd, NULL);
1094 }
1095 EXPORT_SYMBOL_GPL(usbnet_mii_ioctl);
1096
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1097 void usbnet_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
1098 {
1099 struct usbnet *dev = netdev_priv(net);
1100
1101 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1102 strscpy(info->fw_version, dev->driver_info->description,
1103 sizeof(info->fw_version));
1104 usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
1105 }
1106 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1107
usbnet_get_msglevel(struct net_device * net)1108 u32 usbnet_get_msglevel(struct net_device *net)
1109 {
1110 struct usbnet *dev = netdev_priv(net);
1111
1112 return dev->msg_enable;
1113 }
1114 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1115
usbnet_set_msglevel(struct net_device * net,u32 level)1116 void usbnet_set_msglevel(struct net_device *net, u32 level)
1117 {
1118 struct usbnet *dev = netdev_priv(net);
1119
1120 dev->msg_enable = level;
1121 }
1122 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1123
1124 /* drivers may override default ethtool_ops in their bind() routine */
1125 static const struct ethtool_ops usbnet_ethtool_ops = {
1126 .get_link = usbnet_get_link,
1127 .nway_reset = usbnet_nway_reset,
1128 .get_drvinfo = usbnet_get_drvinfo,
1129 .get_msglevel = usbnet_get_msglevel,
1130 .set_msglevel = usbnet_set_msglevel,
1131 .get_ts_info = ethtool_op_get_ts_info,
1132 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1133 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1134 };
1135
1136 /*-------------------------------------------------------------------------*/
1137
__handle_link_change(struct usbnet * dev)1138 static void __handle_link_change(struct usbnet *dev)
1139 {
1140 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1141 return;
1142
1143 if (test_and_clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags))
1144 netif_carrier_on(dev->net);
1145
1146 if (!netif_carrier_ok(dev->net)) {
1147 /* kill URBs for reading packets to save bus bandwidth */
1148 unlink_urbs(dev, &dev->rxq);
1149
1150 /*
1151 * tx_timeout will unlink URBs for sending packets and
1152 * tx queue is stopped by netcore after link becomes off
1153 */
1154 } else {
1155 /* submitting URBs for reading packets */
1156 queue_work(system_bh_wq, &dev->bh_work);
1157 }
1158
1159 /* hard_mtu or rx_urb_size may change during link change */
1160 usbnet_update_max_qlen(dev);
1161
1162 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1163 }
1164
usbnet_set_rx_mode(struct net_device * net)1165 void usbnet_set_rx_mode(struct net_device *net)
1166 {
1167 struct usbnet *dev = netdev_priv(net);
1168
1169 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1170 }
1171 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1172
__handle_set_rx_mode(struct usbnet * dev)1173 static void __handle_set_rx_mode(struct usbnet *dev)
1174 {
1175 if (dev->driver_info->set_rx_mode)
1176 (dev->driver_info->set_rx_mode)(dev);
1177
1178 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1179 }
1180
1181 /* work that cannot be done in interrupt context uses keventd.
1182 *
1183 * NOTE: with 2.5 we could do more of this using completion callbacks,
1184 * especially now that control transfers can be queued.
1185 */
1186 static void
usbnet_deferred_kevent(struct work_struct * work)1187 usbnet_deferred_kevent(struct work_struct *work)
1188 {
1189 struct usbnet *dev =
1190 container_of(work, struct usbnet, kevent);
1191 int status;
1192
1193 /* usb_clear_halt() needs a thread context */
1194 if (test_bit(EVENT_TX_HALT, &dev->flags)) {
1195 unlink_urbs(dev, &dev->txq);
1196 status = usb_autopm_get_interface(dev->intf);
1197 if (status < 0)
1198 goto fail_pipe;
1199 status = usb_clear_halt(dev->udev, dev->out);
1200 usb_autopm_put_interface(dev->intf);
1201 if (status < 0 &&
1202 status != -EPIPE &&
1203 status != -ESHUTDOWN) {
1204 if (netif_msg_tx_err(dev))
1205 fail_pipe:
1206 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1207 status);
1208 } else {
1209 clear_bit(EVENT_TX_HALT, &dev->flags);
1210 if (status != -ESHUTDOWN)
1211 netif_wake_queue(dev->net);
1212 }
1213 }
1214 if (test_bit(EVENT_RX_HALT, &dev->flags)) {
1215 unlink_urbs(dev, &dev->rxq);
1216 status = usb_autopm_get_interface(dev->intf);
1217 if (status < 0)
1218 goto fail_halt;
1219 status = usb_clear_halt(dev->udev, dev->in);
1220 usb_autopm_put_interface(dev->intf);
1221 if (status < 0 &&
1222 status != -EPIPE &&
1223 status != -ESHUTDOWN) {
1224 if (netif_msg_rx_err(dev))
1225 fail_halt:
1226 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1227 status);
1228 } else {
1229 clear_bit(EVENT_RX_HALT, &dev->flags);
1230 if (!usbnet_going_away(dev))
1231 queue_work(system_bh_wq, &dev->bh_work);
1232 }
1233 }
1234
1235 /* work could resubmit itself forever if memory is tight */
1236 if (test_bit(EVENT_RX_MEMORY, &dev->flags)) {
1237 struct urb *urb = NULL;
1238 int resched = 1;
1239
1240 if (netif_running(dev->net))
1241 urb = usb_alloc_urb(0, GFP_KERNEL);
1242 else
1243 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1244 if (urb != NULL) {
1245 clear_bit(EVENT_RX_MEMORY, &dev->flags);
1246 status = usb_autopm_get_interface(dev->intf);
1247 if (status < 0) {
1248 usb_free_urb(urb);
1249 goto fail_lowmem;
1250 }
1251 if (rx_submit(dev, urb, GFP_KERNEL) == -ENOLINK)
1252 resched = 0;
1253 usb_autopm_put_interface(dev->intf);
1254 fail_lowmem:
1255 if (resched)
1256 if (!usbnet_going_away(dev))
1257 queue_work(system_bh_wq, &dev->bh_work);
1258 }
1259 }
1260
1261 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1262 const struct driver_info *info = dev->driver_info;
1263 int retval = 0;
1264
1265 clear_bit(EVENT_LINK_RESET, &dev->flags);
1266 status = usb_autopm_get_interface(dev->intf);
1267 if (status < 0)
1268 goto skip_reset;
1269 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1270 usb_autopm_put_interface(dev->intf);
1271 skip_reset:
1272 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1273 retval,
1274 dev->udev->bus->bus_name,
1275 dev->udev->devpath,
1276 info->description);
1277 } else {
1278 usb_autopm_put_interface(dev->intf);
1279 }
1280
1281 /* handle link change from link resetting */
1282 __handle_link_change(dev);
1283 }
1284
1285 if (test_bit(EVENT_LINK_CHANGE, &dev->flags))
1286 __handle_link_change(dev);
1287
1288 if (test_bit(EVENT_SET_RX_MODE, &dev->flags))
1289 __handle_set_rx_mode(dev);
1290
1291
1292 if (dev->flags)
1293 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1294 }
1295
1296 /*-------------------------------------------------------------------------*/
1297
tx_complete(struct urb * urb)1298 static void tx_complete(struct urb *urb)
1299 {
1300 struct sk_buff *skb = (struct sk_buff *) urb->context;
1301 struct skb_data *entry = (struct skb_data *) skb->cb;
1302 struct usbnet *dev = entry->dev;
1303
1304 if (urb->status == 0) {
1305 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1306 unsigned long flags;
1307
1308 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1309 u64_stats_add(&stats64->tx_packets, entry->packets);
1310 u64_stats_add(&stats64->tx_bytes, entry->length);
1311 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1312 } else {
1313 dev->net->stats.tx_errors++;
1314
1315 switch (urb->status) {
1316 case -EPIPE:
1317 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1318 break;
1319
1320 /* software-driven interface shutdown */
1321 case -ECONNRESET: // async unlink
1322 case -ESHUTDOWN: // hardware gone
1323 break;
1324
1325 /* like rx, tx gets controller i/o faults during hub_wq
1326 * delays and so it uses the same throttling mechanism.
1327 */
1328 case -EPROTO:
1329 case -ETIME:
1330 case -EILSEQ:
1331 usb_mark_last_busy(dev->udev);
1332 if (!timer_pending(&dev->delay)) {
1333 mod_timer(&dev->delay,
1334 jiffies + THROTTLE_JIFFIES);
1335 netif_dbg(dev, link, dev->net,
1336 "tx throttle %d\n", urb->status);
1337 }
1338 netif_stop_queue(dev->net);
1339 break;
1340 default:
1341 netif_dbg(dev, tx_err, dev->net,
1342 "tx err %d\n", entry->urb->status);
1343 break;
1344 }
1345 }
1346
1347 usb_autopm_put_interface_async(dev->intf);
1348 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1349 }
1350
1351 /*-------------------------------------------------------------------------*/
1352
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1353 void usbnet_tx_timeout(struct net_device *net, unsigned int txqueue)
1354 {
1355 struct usbnet *dev = netdev_priv(net);
1356
1357 unlink_urbs(dev, &dev->txq);
1358 queue_work(system_bh_wq, &dev->bh_work);
1359 /* this needs to be handled individually because the generic layer
1360 * doesn't know what is sufficient and could not restore private
1361 * information if a remedy of an unconditional reset were used.
1362 */
1363 if (dev->driver_info->recover)
1364 (dev->driver_info->recover)(dev);
1365 }
1366 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1367
1368 /*-------------------------------------------------------------------------*/
1369
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1370 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1371 {
1372 unsigned num_sgs, total_len = 0;
1373 int i, s = 0;
1374
1375 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1376 if (num_sgs == 1)
1377 return 0;
1378
1379 /* reserve one for zero packet */
1380 urb->sg = kmalloc_objs(struct scatterlist, num_sgs + 1, GFP_ATOMIC);
1381 if (!urb->sg)
1382 return -ENOMEM;
1383
1384 urb->num_sgs = num_sgs;
1385 sg_init_table(urb->sg, urb->num_sgs + 1);
1386
1387 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1388 total_len += skb_headlen(skb);
1389
1390 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1391 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1392
1393 total_len += skb_frag_size(f);
1394 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1395 skb_frag_off(f));
1396 }
1397 urb->transfer_buffer_length = total_len;
1398
1399 return 1;
1400 }
1401
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1402 netdev_tx_t usbnet_start_xmit(struct sk_buff *skb, struct net_device *net)
1403 {
1404 struct usbnet *dev = netdev_priv(net);
1405 unsigned int length;
1406 struct urb *urb = NULL;
1407 struct skb_data *entry;
1408 const struct driver_info *info = dev->driver_info;
1409 unsigned long flags;
1410 int retval;
1411
1412 if (skb)
1413 skb_tx_timestamp(skb);
1414
1415 // some devices want funky USB-level framing, for
1416 // win32 driver (usually) and/or hardware quirks
1417 if (info->tx_fixup) {
1418 skb = info->tx_fixup(dev, skb, GFP_ATOMIC);
1419 if (!skb) {
1420 /* packet collected; minidriver waiting for more */
1421 if (info->flags & FLAG_MULTI_PACKET)
1422 goto not_drop;
1423 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1424 goto drop;
1425 }
1426 }
1427
1428 urb = usb_alloc_urb(0, GFP_ATOMIC);
1429 if (!urb) {
1430 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1431 goto drop;
1432 }
1433
1434 entry = (struct skb_data *) skb->cb;
1435 entry->urb = urb;
1436 entry->dev = dev;
1437
1438 usb_fill_bulk_urb(urb, dev->udev, dev->out,
1439 skb->data, skb->len, tx_complete, skb);
1440 if (dev->can_dma_sg) {
1441 if (build_dma_sg(skb, urb) < 0)
1442 goto drop;
1443 }
1444 length = urb->transfer_buffer_length;
1445
1446 /* don't assume the hardware handles USB_ZERO_PACKET
1447 * NOTE: strictly conforming cdc-ether devices should expect
1448 * the ZLP here, but ignore the one-byte packet.
1449 * NOTE2: CDC NCM specification is different from CDC ECM when
1450 * handling ZLP/short packets, so cdc_ncm driver will make short
1451 * packet itself if needed.
1452 */
1453 if (length % dev->maxpacket == 0) {
1454 if (!(info->flags & FLAG_SEND_ZLP)) {
1455 if (!(info->flags & FLAG_MULTI_PACKET)) {
1456 length++;
1457 if (skb_tailroom(skb) && !urb->num_sgs) {
1458 skb->data[skb->len] = 0;
1459 __skb_put(skb, 1);
1460 } else if (urb->num_sgs)
1461 sg_set_buf(&urb->sg[urb->num_sgs++],
1462 dev->padding_pkt, 1);
1463 }
1464 } else
1465 urb->transfer_flags |= URB_ZERO_PACKET;
1466 }
1467 urb->transfer_buffer_length = length;
1468
1469 if (info->flags & FLAG_MULTI_PACKET) {
1470 /* Driver has set number of packets and a length delta.
1471 * Calculate the complete length and ensure that it's
1472 * positive.
1473 */
1474 entry->length += length;
1475 if (WARN_ON_ONCE(entry->length <= 0))
1476 entry->length = length;
1477 } else {
1478 usbnet_set_skb_tx_stats(skb, 1, length);
1479 }
1480
1481 spin_lock_irqsave(&dev->txq.lock, flags);
1482 retval = usb_autopm_get_interface_async(dev->intf);
1483 if (retval < 0) {
1484 spin_unlock_irqrestore(&dev->txq.lock, flags);
1485 goto drop;
1486 }
1487 if (netif_queue_stopped(net)) {
1488 usb_autopm_put_interface_async(dev->intf);
1489 spin_unlock_irqrestore(&dev->txq.lock, flags);
1490 goto drop;
1491 }
1492
1493 #ifdef CONFIG_PM
1494 /* if this triggers the device is still a sleep */
1495 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1496 /* transmission will be done in resume */
1497 usb_anchor_urb(urb, &dev->deferred);
1498 /* no use to process more packets */
1499 netif_stop_queue(net);
1500 usb_put_urb(urb);
1501 spin_unlock_irqrestore(&dev->txq.lock, flags);
1502 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1503 goto deferred;
1504 }
1505 #endif
1506
1507 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1508 case -EPIPE:
1509 netif_stop_queue(net);
1510 usbnet_defer_kevent(dev, EVENT_TX_HALT);
1511 usb_autopm_put_interface_async(dev->intf);
1512 break;
1513 default:
1514 usb_autopm_put_interface_async(dev->intf);
1515 netif_dbg(dev, tx_err, dev->net,
1516 "tx: submit urb err %d\n", retval);
1517 break;
1518 case 0:
1519 netif_trans_update(net);
1520 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1521 netdev_sent_queue(net, skb->len);
1522 if (dev->txq.qlen >= TX_QLEN (dev))
1523 netif_stop_queue (net);
1524 }
1525 spin_unlock_irqrestore(&dev->txq.lock, flags);
1526
1527 if (retval) {
1528 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1529 drop:
1530 dev->net->stats.tx_dropped++;
1531 not_drop:
1532 if (skb)
1533 dev_kfree_skb_any(skb);
1534 if (urb) {
1535 kfree(urb->sg);
1536 usb_free_urb(urb);
1537 }
1538 } else
1539 netif_dbg(dev, tx_queued, dev->net,
1540 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1541 #ifdef CONFIG_PM
1542 deferred:
1543 #endif
1544 return NETDEV_TX_OK;
1545 }
1546 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1547
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1548 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1549 {
1550 struct urb *urb;
1551 int i;
1552 int ret = 0;
1553
1554 /* don't refill the queue all at once */
1555 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1556 urb = usb_alloc_urb(0, flags);
1557 if (urb != NULL) {
1558 ret = rx_submit(dev, urb, flags);
1559 if (ret)
1560 goto err;
1561 } else {
1562 ret = -ENOMEM;
1563 goto err;
1564 }
1565 }
1566 err:
1567 return ret;
1568 }
1569
usb_free_skb(struct sk_buff * skb)1570 static inline void usb_free_skb(struct sk_buff *skb)
1571 {
1572 struct skb_data *entry = (struct skb_data *)skb->cb;
1573
1574 usb_free_urb(entry->urb);
1575 dev_kfree_skb(skb);
1576 }
1577
1578 /*-------------------------------------------------------------------------*/
1579
1580 // work (work deferred from completions, in_irq) or timer
1581
usbnet_bh(struct timer_list * t)1582 static void usbnet_bh(struct timer_list *t)
1583 {
1584 struct usbnet *dev = timer_container_of(dev, t, delay);
1585 unsigned int bytes_compl = 0, pkts_compl = 0;
1586 struct sk_buff *skb;
1587 struct skb_data *entry;
1588
1589 while ((skb = skb_dequeue (&dev->done))) {
1590 entry = (struct skb_data *) skb->cb;
1591 switch (entry->state) {
1592 case rx_done:
1593 if (rx_process(dev, skb))
1594 usb_free_skb(skb);
1595 continue;
1596 case tx_done:
1597 bytes_compl += skb->len;
1598 pkts_compl++;
1599 kfree(entry->urb->sg);
1600 fallthrough;
1601 case rx_cleanup:
1602 usb_free_skb(skb);
1603 continue;
1604 default:
1605 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1606 }
1607 }
1608
1609 spin_lock_bh(&dev->bql_spinlock);
1610 netdev_completed_queue(dev->net, pkts_compl, bytes_compl);
1611 spin_unlock_bh(&dev->bql_spinlock);
1612
1613 /* restart RX again after disabling due to high error rate */
1614 clear_bit(EVENT_RX_KILL, &dev->flags);
1615
1616 /* waiting for all pending urbs to complete?
1617 * only then can we forgo submitting anew
1618 */
1619 if (waitqueue_active(&dev->wait)) {
1620 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1621 wake_up_all(&dev->wait);
1622
1623 // or are we maybe short a few urbs?
1624 } else if (netif_running (dev->net) &&
1625 netif_device_present (dev->net) &&
1626 netif_carrier_ok(dev->net) &&
1627 !usbnet_going_away(dev) &&
1628 !timer_pending(&dev->delay) &&
1629 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1630 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1631 int temp = dev->rxq.qlen;
1632
1633 if (temp < RX_QLEN(dev)) {
1634 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1635 return;
1636 if (temp != dev->rxq.qlen)
1637 netif_dbg(dev, link, dev->net,
1638 "rxqlen %d --> %d\n",
1639 temp, dev->rxq.qlen);
1640 if (dev->rxq.qlen < RX_QLEN(dev))
1641 queue_work(system_bh_wq, &dev->bh_work);
1642 }
1643 if (dev->txq.qlen < TX_QLEN (dev))
1644 netif_wake_queue(dev->net);
1645 }
1646 }
1647
usbnet_bh_work(struct work_struct * work)1648 static void usbnet_bh_work(struct work_struct *work)
1649 {
1650 struct usbnet *dev = from_work(dev, work, bh_work);
1651
1652 usbnet_bh(&dev->delay);
1653 }
1654
1655
1656 /*-------------------------------------------------------------------------
1657 *
1658 * USB Device Driver support
1659 *
1660 *-------------------------------------------------------------------------*/
1661
1662 // precondition: never called in_interrupt
1663
usbnet_disconnect(struct usb_interface * intf)1664 void usbnet_disconnect(struct usb_interface *intf)
1665 {
1666 struct usbnet *dev;
1667 struct usb_device *xdev;
1668 struct net_device *net;
1669 struct urb *urb;
1670
1671 dev = usb_get_intfdata(intf);
1672 usb_set_intfdata(intf, NULL);
1673 if (!dev)
1674 return;
1675 usbnet_mark_going_away(dev);
1676
1677 xdev = interface_to_usbdev(intf);
1678
1679 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1680 intf->dev.driver->name,
1681 xdev->bus->bus_name, xdev->devpath,
1682 dev->driver_info->description);
1683
1684 net = dev->net;
1685 unregister_netdev(net);
1686
1687 cancel_work_sync(&dev->kevent);
1688
1689 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1690 dev_kfree_skb(urb->context);
1691 kfree(urb->sg);
1692 usb_free_urb(urb);
1693 }
1694
1695 if (dev->driver_info->unbind)
1696 dev->driver_info->unbind(dev, intf);
1697
1698 usb_kill_urb(dev->interrupt);
1699 usb_free_urb(dev->interrupt);
1700 kfree(dev->padding_pkt);
1701
1702 free_netdev(net);
1703 }
1704 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1705
1706 static const struct net_device_ops usbnet_netdev_ops = {
1707 .ndo_open = usbnet_open,
1708 .ndo_stop = usbnet_stop,
1709 .ndo_start_xmit = usbnet_start_xmit,
1710 .ndo_tx_timeout = usbnet_tx_timeout,
1711 .ndo_set_rx_mode = usbnet_set_rx_mode,
1712 .ndo_change_mtu = usbnet_change_mtu,
1713 .ndo_set_mac_address = eth_mac_addr,
1714 .ndo_validate_addr = eth_validate_addr,
1715 };
1716
1717 /*-------------------------------------------------------------------------*/
1718
1719 // precondition: never called in_interrupt
1720
1721 static const struct device_type wlan_type = {
1722 .name = "wlan",
1723 };
1724
1725 static const struct device_type wwan_type = {
1726 .name = "wwan",
1727 };
1728
1729 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1730 usbnet_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1731 {
1732 struct usbnet *dev;
1733 struct net_device *net;
1734 struct usb_host_interface *interface;
1735 const struct driver_info *info;
1736 struct usb_device *xdev;
1737 int status;
1738 const char *name;
1739 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1740
1741 /* usbnet already took usb runtime pm, so have to enable the feature
1742 * for usb interface, otherwise usb_autopm_get_interface may return
1743 * failure if RUNTIME_PM is enabled.
1744 */
1745 if (!driver->supports_autosuspend) {
1746 driver->supports_autosuspend = 1;
1747 pm_runtime_enable(&udev->dev);
1748 }
1749
1750 name = udev->dev.driver->name;
1751 info = (const struct driver_info *) prod->driver_info;
1752 if (!info) {
1753 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1754 return -ENODEV;
1755 }
1756 xdev = interface_to_usbdev(udev);
1757 interface = udev->cur_altsetting;
1758
1759 status = -ENOMEM;
1760
1761 // set up our own records
1762 net = alloc_etherdev(sizeof(*dev));
1763 if (!net)
1764 goto out;
1765
1766 /* netdev_printk() needs this so do it as early as possible */
1767 SET_NETDEV_DEV(net, &udev->dev);
1768
1769 dev = netdev_priv(net);
1770 dev->udev = xdev;
1771 dev->intf = udev;
1772 dev->driver_info = info;
1773 dev->driver_name = name;
1774 dev->rx_speed = SPEED_UNSET;
1775 dev->tx_speed = SPEED_UNSET;
1776
1777 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1778 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1779 init_waitqueue_head(&dev->wait);
1780 skb_queue_head_init (&dev->rxq);
1781 skb_queue_head_init (&dev->txq);
1782 skb_queue_head_init (&dev->done);
1783 skb_queue_head_init(&dev->rxq_pause);
1784 spin_lock_init(&dev->bql_spinlock);
1785 INIT_WORK(&dev->bh_work, usbnet_bh_work);
1786 INIT_WORK(&dev->kevent, usbnet_deferred_kevent);
1787 init_usb_anchor(&dev->deferred);
1788 timer_setup(&dev->delay, usbnet_bh, 0);
1789 mutex_init(&dev->phy_mutex);
1790 mutex_init(&dev->interrupt_mutex);
1791 dev->interrupt_count = 0;
1792
1793 dev->net = net;
1794 strscpy(net->name, "usb%d", sizeof(net->name));
1795
1796 /* rx and tx sides can use different message sizes;
1797 * bind() should set rx_urb_size in that case.
1798 */
1799 dev->hard_mtu = net->mtu + net->hard_header_len;
1800 net->min_mtu = 0;
1801 net->max_mtu = ETH_MAX_MTU;
1802
1803 net->netdev_ops = &usbnet_netdev_ops;
1804 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1805 net->ethtool_ops = &usbnet_ethtool_ops;
1806 net->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1807
1808 // allow device-specific bind/init procedures
1809 // NOTE net->name still not usable ...
1810 if (info->bind) {
1811 status = info->bind(dev, udev);
1812 if (status < 0)
1813 goto out1;
1814
1815 /* heuristic: rename to "eth%d" if we are not sure this link
1816 * is two-host (these links keep "usb%d")
1817 */
1818 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1819 !usbnet_needs_usb_name_format(dev, net))
1820 strscpy(net->name, "eth%d", sizeof(net->name));
1821 /* WLAN devices should always be named "wlan%d" */
1822 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1823 strscpy(net->name, "wlan%d", sizeof(net->name));
1824 /* WWAN devices should always be named "wwan%d" */
1825 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1826 strscpy(net->name, "wwan%d", sizeof(net->name));
1827
1828 /* devices that cannot do ARP */
1829 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1830 net->flags |= IFF_NOARP;
1831
1832 if (net->max_mtu > (dev->hard_mtu - net->hard_header_len))
1833 net->max_mtu = dev->hard_mtu - net->hard_header_len;
1834
1835 if (net->mtu > net->max_mtu)
1836 net->mtu = net->max_mtu;
1837
1838 } else if (!info->in || !info->out)
1839 status = usbnet_get_endpoints(dev, udev);
1840 else {
1841 u8 ep_addrs[3] = {
1842 info->in + USB_DIR_IN, info->out + USB_DIR_OUT, 0
1843 };
1844
1845 dev->in = usb_rcvbulkpipe(xdev, info->in);
1846 dev->out = usb_sndbulkpipe(xdev, info->out);
1847 if (!(info->flags & FLAG_NO_SETINT))
1848 status = usb_set_interface(xdev,
1849 interface->desc.bInterfaceNumber,
1850 interface->desc.bAlternateSetting);
1851 else
1852 status = 0;
1853
1854 if (status == 0 && !usb_check_bulk_endpoints(udev, ep_addrs))
1855 status = -EINVAL;
1856 }
1857 if (status >= 0 && dev->status)
1858 status = init_status(dev, udev);
1859 if (status < 0)
1860 goto out3;
1861
1862 if (!dev->rx_urb_size)
1863 dev->rx_urb_size = dev->hard_mtu;
1864 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1865 if (dev->maxpacket == 0) {
1866 /* that is a broken device */
1867 status = -ENODEV;
1868 goto out4;
1869 }
1870
1871 /* this flags the device for user space */
1872 if (!is_valid_ether_addr(net->dev_addr))
1873 eth_hw_addr_random(net);
1874
1875 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1876 SET_NETDEV_DEVTYPE(net, &wlan_type);
1877 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1878 SET_NETDEV_DEVTYPE(net, &wwan_type);
1879
1880 /* initialize max rx_qlen and tx_qlen */
1881 usbnet_update_max_qlen(dev);
1882
1883 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1884 !(info->flags & FLAG_MULTI_PACKET)) {
1885 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1886 if (!dev->padding_pkt) {
1887 status = -ENOMEM;
1888 goto out4;
1889 }
1890 }
1891
1892 status = register_netdev(net);
1893 if (status)
1894 goto out5;
1895 netif_info(dev, probe, dev->net,
1896 "register '%s' at usb-%s-%s, %s, %pM\n",
1897 udev->dev.driver->name,
1898 xdev->bus->bus_name, xdev->devpath,
1899 dev->driver_info->description,
1900 net->dev_addr);
1901
1902 // ok, it's ready to go.
1903 usb_set_intfdata(udev, dev);
1904
1905 netif_device_attach(net);
1906
1907 if (dev->driver_info->flags & FLAG_LINK_INTR)
1908 usbnet_link_change(dev, 0, 0);
1909
1910 return 0;
1911
1912 out5:
1913 kfree(dev->padding_pkt);
1914 out4:
1915 usb_free_urb(dev->interrupt);
1916 out3:
1917 if (info->unbind)
1918 info->unbind(dev, udev);
1919 out1:
1920 /* subdrivers must undo all they did in bind() if they
1921 * fail it, but we may fail later and a deferred kevent
1922 * may trigger an error resubmitting itself and, worse,
1923 * schedule a timer. So we kill it all just in case.
1924 */
1925 usbnet_mark_going_away(dev);
1926 cancel_work_sync(&dev->kevent);
1927 timer_delete_sync(&dev->delay);
1928 free_netdev(net);
1929 out:
1930 return status;
1931 }
1932 EXPORT_SYMBOL_GPL(usbnet_probe);
1933
1934 /*-------------------------------------------------------------------------*/
1935
1936 /*
1937 * suspend the whole driver as soon as the first interface is suspended
1938 * resume only when the last interface is resumed
1939 */
1940
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1941 int usbnet_suspend(struct usb_interface *intf, pm_message_t message)
1942 {
1943 struct usbnet *dev = usb_get_intfdata(intf);
1944
1945 if (!dev->suspend_count++) {
1946 spin_lock_irq(&dev->txq.lock);
1947 /* don't autosuspend while transmitting */
1948 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1949 dev->suspend_count--;
1950 spin_unlock_irq(&dev->txq.lock);
1951 return -EBUSY;
1952 } else {
1953 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1954 spin_unlock_irq(&dev->txq.lock);
1955 }
1956 /*
1957 * accelerate emptying of the rx and queues, to avoid
1958 * having everything error out.
1959 */
1960 netif_device_detach(dev->net);
1961 usbnet_terminate_urbs(dev);
1962 __usbnet_status_stop_force(dev);
1963
1964 /*
1965 * reattach so runtime management can use and
1966 * wake the device
1967 */
1968 netif_device_attach(dev->net);
1969 }
1970 return 0;
1971 }
1972 EXPORT_SYMBOL_GPL(usbnet_suspend);
1973
usbnet_resume(struct usb_interface * intf)1974 int usbnet_resume(struct usb_interface *intf)
1975 {
1976 struct usbnet *dev = usb_get_intfdata(intf);
1977 struct sk_buff *skb;
1978 struct urb *res;
1979 int retval;
1980
1981 if (!--dev->suspend_count) {
1982 /* resume interrupt URB if it was previously submitted */
1983 __usbnet_status_start_force(dev, GFP_NOIO);
1984
1985 spin_lock_irq(&dev->txq.lock);
1986 while ((res = usb_get_from_anchor(&dev->deferred))) {
1987
1988 skb = (struct sk_buff *)res->context;
1989 retval = usb_submit_urb(res, GFP_ATOMIC);
1990 if (retval < 0) {
1991 dev_kfree_skb_any(skb);
1992 kfree(res->sg);
1993 usb_free_urb(res);
1994 usb_autopm_put_interface_async(dev->intf);
1995 } else {
1996 netif_trans_update(dev->net);
1997 __skb_queue_tail(&dev->txq, skb);
1998 netdev_sent_queue(dev->net, skb->len);
1999 }
2000 }
2001
2002 smp_mb();
2003 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
2004 spin_unlock_irq(&dev->txq.lock);
2005
2006 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
2007 /* handle remote wakeup ASAP
2008 * we cannot race against stop
2009 */
2010 if (netif_device_present(dev->net) &&
2011 !timer_pending(&dev->delay) &&
2012 !test_bit(EVENT_RX_HALT, &dev->flags))
2013 rx_alloc_submit(dev, GFP_NOIO);
2014
2015 if (!(dev->txq.qlen >= TX_QLEN(dev)))
2016 netif_tx_wake_all_queues(dev->net);
2017 queue_work(system_bh_wq, &dev->bh_work);
2018 }
2019 }
2020
2021 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
2022 usb_autopm_get_interface_no_resume(intf);
2023
2024 return 0;
2025 }
2026 EXPORT_SYMBOL_GPL(usbnet_resume);
2027
2028 /*
2029 * Either a subdriver implements manage_power, then it is assumed to always
2030 * be ready to be suspended or it reports the readiness to be suspended
2031 * explicitly
2032 */
usbnet_device_suggests_idle(struct usbnet * dev)2033 void usbnet_device_suggests_idle(struct usbnet *dev)
2034 {
2035 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
2036 dev->intf->needs_remote_wakeup = 1;
2037 usb_autopm_put_interface_async(dev->intf);
2038 }
2039 }
2040 EXPORT_SYMBOL(usbnet_device_suggests_idle);
2041
2042 /*
2043 * For devices that can do without special commands
2044 */
usbnet_manage_power(struct usbnet * dev,int on)2045 int usbnet_manage_power(struct usbnet *dev, int on)
2046 {
2047 dev->intf->needs_remote_wakeup = on;
2048 return 0;
2049 }
2050 EXPORT_SYMBOL(usbnet_manage_power);
2051
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)2052 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
2053 {
2054 /* update link after link is reseted */
2055 if (link && !need_reset) {
2056 set_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2057 } else {
2058 clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2059 netif_carrier_off(dev->net);
2060 }
2061
2062 if (need_reset && link)
2063 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
2064 else
2065 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
2066 }
2067 EXPORT_SYMBOL(usbnet_link_change);
2068
2069 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2070 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2071 u16 value, u16 index, void *data, u16 size)
2072 {
2073 void *buf = NULL;
2074 int err = -ENOMEM;
2075
2076 netdev_dbg(dev->net, "usbnet_read_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 (size) {
2081 buf = kmalloc(size, GFP_NOIO);
2082 if (!buf)
2083 goto out;
2084 }
2085
2086 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2087 cmd, reqtype, value, index, buf, size,
2088 USB_CTRL_GET_TIMEOUT);
2089 if (err > 0 && err <= size) {
2090 if (data)
2091 memcpy(data, buf, err);
2092 else
2093 netdev_dbg(dev->net,
2094 "Huh? Data requested but thrown away.\n");
2095 }
2096 kfree(buf);
2097 out:
2098 return err;
2099 }
2100
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2101 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2102 u16 value, u16 index, const void *data,
2103 u16 size)
2104 {
2105 void *buf = NULL;
2106 int err = -ENOMEM;
2107
2108 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2109 " value=0x%04x index=0x%04x size=%d\n",
2110 cmd, reqtype, value, index, size);
2111
2112 if (data) {
2113 buf = kmemdup(data, size, GFP_NOIO);
2114 if (!buf)
2115 goto out;
2116 } else {
2117 if (size) {
2118 WARN_ON_ONCE(1);
2119 err = -EINVAL;
2120 goto out;
2121 }
2122 }
2123
2124 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2125 cmd, reqtype, value, index, buf, size,
2126 USB_CTRL_SET_TIMEOUT);
2127 kfree(buf);
2128
2129 out:
2130 return err;
2131 }
2132
2133 /*
2134 * The function can't be called inside suspend/resume callback,
2135 * otherwise deadlock will be caused.
2136 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2137 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2138 u16 value, u16 index, void *data, u16 size)
2139 {
2140 int ret;
2141
2142 if (usb_autopm_get_interface(dev->intf) < 0)
2143 return -ENODEV;
2144 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2145 data, size);
2146 usb_autopm_put_interface(dev->intf);
2147 return ret;
2148 }
2149 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2150
2151 /*
2152 * The function can't be called inside suspend/resume callback,
2153 * otherwise deadlock will be caused.
2154 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2155 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2156 u16 value, u16 index, const void *data, u16 size)
2157 {
2158 int ret;
2159
2160 if (usb_autopm_get_interface(dev->intf) < 0)
2161 return -ENODEV;
2162 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2163 data, size);
2164 usb_autopm_put_interface(dev->intf);
2165 return ret;
2166 }
2167 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2168
2169 /*
2170 * The function can be called inside suspend/resume callback safely
2171 * and should only be called by suspend/resume callback generally.
2172 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2173 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2174 u16 value, u16 index, void *data, u16 size)
2175 {
2176 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2177 data, size);
2178 }
2179 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2180
2181 /*
2182 * The function can be called inside suspend/resume callback safely
2183 * and should only be called by suspend/resume callback generally.
2184 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2185 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2186 u16 value, u16 index, const void *data,
2187 u16 size)
2188 {
2189 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2190 data, size);
2191 }
2192 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2193
usbnet_async_cmd_cb(struct urb * urb)2194 static void usbnet_async_cmd_cb(struct urb *urb)
2195 {
2196 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2197 int status = urb->status;
2198
2199 if (status < 0)
2200 dev_dbg(&urb->dev->dev, "%s failed with %d",
2201 __func__, status);
2202
2203 kfree(req);
2204 usb_free_urb(urb);
2205 }
2206
2207 /*
2208 * The caller must make sure that device can't be put into suspend
2209 * state until the control URB completes.
2210 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2211 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2212 u16 value, u16 index, const void *data, u16 size)
2213 {
2214 struct usb_ctrlrequest *req;
2215 struct urb *urb;
2216 int err = -ENOMEM;
2217 void *buf = NULL;
2218
2219 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2220 " value=0x%04x index=0x%04x size=%d\n",
2221 cmd, reqtype, value, index, size);
2222
2223 urb = usb_alloc_urb(0, GFP_ATOMIC);
2224 if (!urb)
2225 goto fail;
2226
2227 if (data) {
2228 buf = kmemdup(data, size, GFP_ATOMIC);
2229 if (!buf) {
2230 netdev_err(dev->net, "Error allocating buffer"
2231 " in %s!\n", __func__);
2232 goto fail_free_urb;
2233 }
2234 }
2235
2236 req = kmalloc_obj(struct usb_ctrlrequest, GFP_ATOMIC);
2237 if (!req)
2238 goto fail_free_buf;
2239
2240 req->bRequestType = reqtype;
2241 req->bRequest = cmd;
2242 req->wValue = cpu_to_le16(value);
2243 req->wIndex = cpu_to_le16(index);
2244 req->wLength = cpu_to_le16(size);
2245
2246 usb_fill_control_urb(urb, dev->udev,
2247 usb_sndctrlpipe(dev->udev, 0),
2248 (void *)req, buf, size,
2249 usbnet_async_cmd_cb, req);
2250 urb->transfer_flags |= URB_FREE_BUFFER;
2251
2252 err = usb_submit_urb(urb, GFP_ATOMIC);
2253 if (err < 0) {
2254 netdev_err(dev->net, "Error submitting the control"
2255 " message: status=%d\n", err);
2256 goto fail_free_all;
2257 }
2258 return 0;
2259
2260 fail_free_all:
2261 kfree(req);
2262 fail_free_buf:
2263 kfree(buf);
2264 /*
2265 * avoid a double free
2266 * needed because the flag can be set only
2267 * after filling the URB
2268 */
2269 urb->transfer_flags = 0;
2270 fail_free_urb:
2271 usb_free_urb(urb);
2272 fail:
2273 return err;
2274
2275 }
2276 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2277 /*-------------------------------------------------------------------------*/
2278
usbnet_init(void)2279 static int __init usbnet_init(void)
2280 {
2281 /* Compiler should optimize this out. */
2282 BUILD_BUG_ON(
2283 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2284
2285 return 0;
2286 }
2287 module_init(usbnet_init);
2288
usbnet_exit(void)2289 static void __exit usbnet_exit(void)
2290 {
2291 }
2292 module_exit(usbnet_exit);
2293
2294 MODULE_AUTHOR("David Brownell");
2295 MODULE_DESCRIPTION("USB network driver framework");
2296 MODULE_LICENSE("GPL");
2297