xref: /openbmc/linux/drivers/usb/core/devio.c (revision f7777dcc)
1 /*****************************************************************************/
2 
3 /*
4  *      devio.c  --  User space communication with USB devices.
5  *
6  *      Copyright (C) 1999-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
7  *
8  *      This program is free software; you can redistribute it and/or modify
9  *      it under the terms of the GNU General Public License as published by
10  *      the Free Software Foundation; either version 2 of the License, or
11  *      (at your option) any later version.
12  *
13  *      This program is distributed in the hope that it will be useful,
14  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *      GNU General Public License for more details.
17  *
18  *      You should have received a copy of the GNU General Public License
19  *      along with this program; if not, write to the Free Software
20  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  *
22  *  This file implements the usbfs/x/y files, where
23  *  x is the bus number and y the device number.
24  *
25  *  It allows user space programs/"drivers" to communicate directly
26  *  with USB devices without intervening kernel driver.
27  *
28  *  Revision history
29  *    22.12.1999   0.1   Initial release (split from proc_usb.c)
30  *    04.01.2000   0.2   Turned into its own filesystem
31  *    30.09.2005   0.3   Fix user-triggerable oops in async URB delivery
32  *    			 (CAN-2005-3055)
33  */
34 
35 /*****************************************************************************/
36 
37 #include <linux/fs.h>
38 #include <linux/mm.h>
39 #include <linux/slab.h>
40 #include <linux/signal.h>
41 #include <linux/poll.h>
42 #include <linux/module.h>
43 #include <linux/string.h>
44 #include <linux/usb.h>
45 #include <linux/usbdevice_fs.h>
46 #include <linux/usb/hcd.h>	/* for usbcore internals */
47 #include <linux/cdev.h>
48 #include <linux/notifier.h>
49 #include <linux/security.h>
50 #include <linux/user_namespace.h>
51 #include <linux/scatterlist.h>
52 #include <linux/uaccess.h>
53 #include <asm/byteorder.h>
54 #include <linux/moduleparam.h>
55 
56 #include "usb.h"
57 
58 #define USB_MAXBUS			64
59 #define USB_DEVICE_MAX			(USB_MAXBUS * 128)
60 #define USB_SG_SIZE			16384 /* split-size for large txs */
61 
62 /* Mutual exclusion for removal, open, and release */
63 DEFINE_MUTEX(usbfs_mutex);
64 
65 struct dev_state {
66 	struct list_head list;      /* state list */
67 	struct usb_device *dev;
68 	struct file *file;
69 	spinlock_t lock;            /* protects the async urb lists */
70 	struct list_head async_pending;
71 	struct list_head async_completed;
72 	wait_queue_head_t wait;     /* wake up if a request completed */
73 	unsigned int discsignr;
74 	struct pid *disc_pid;
75 	const struct cred *cred;
76 	void __user *disccontext;
77 	unsigned long ifclaimed;
78 	u32 secid;
79 	u32 disabled_bulk_eps;
80 };
81 
82 struct async {
83 	struct list_head asynclist;
84 	struct dev_state *ps;
85 	struct pid *pid;
86 	const struct cred *cred;
87 	unsigned int signr;
88 	unsigned int ifnum;
89 	void __user *userbuffer;
90 	void __user *userurb;
91 	struct urb *urb;
92 	unsigned int mem_usage;
93 	int status;
94 	u32 secid;
95 	u8 bulk_addr;
96 	u8 bulk_status;
97 };
98 
99 static bool usbfs_snoop;
100 module_param(usbfs_snoop, bool, S_IRUGO | S_IWUSR);
101 MODULE_PARM_DESC(usbfs_snoop, "true to log all usbfs traffic");
102 
103 #define snoop(dev, format, arg...)				\
104 	do {							\
105 		if (usbfs_snoop)				\
106 			dev_info(dev , format , ## arg);	\
107 	} while (0)
108 
109 enum snoop_when {
110 	SUBMIT, COMPLETE
111 };
112 
113 #define USB_DEVICE_DEV		MKDEV(USB_DEVICE_MAJOR, 0)
114 
115 /* Limit on the total amount of memory we can allocate for transfers */
116 static unsigned usbfs_memory_mb = 16;
117 module_param(usbfs_memory_mb, uint, 0644);
118 MODULE_PARM_DESC(usbfs_memory_mb,
119 		"maximum MB allowed for usbfs buffers (0 = no limit)");
120 
121 /* Hard limit, necessary to avoid aithmetic overflow */
122 #define USBFS_XFER_MAX		(UINT_MAX / 2 - 1000000)
123 
124 static atomic_t usbfs_memory_usage;	/* Total memory currently allocated */
125 
126 /* Check whether it's okay to allocate more memory for a transfer */
127 static int usbfs_increase_memory_usage(unsigned amount)
128 {
129 	unsigned lim;
130 
131 	/*
132 	 * Convert usbfs_memory_mb to bytes, avoiding overflows.
133 	 * 0 means use the hard limit (effectively unlimited).
134 	 */
135 	lim = ACCESS_ONCE(usbfs_memory_mb);
136 	if (lim == 0 || lim > (USBFS_XFER_MAX >> 20))
137 		lim = USBFS_XFER_MAX;
138 	else
139 		lim <<= 20;
140 
141 	atomic_add(amount, &usbfs_memory_usage);
142 	if (atomic_read(&usbfs_memory_usage) <= lim)
143 		return 0;
144 	atomic_sub(amount, &usbfs_memory_usage);
145 	return -ENOMEM;
146 }
147 
148 /* Memory for a transfer is being deallocated */
149 static void usbfs_decrease_memory_usage(unsigned amount)
150 {
151 	atomic_sub(amount, &usbfs_memory_usage);
152 }
153 
154 static int connected(struct dev_state *ps)
155 {
156 	return (!list_empty(&ps->list) &&
157 			ps->dev->state != USB_STATE_NOTATTACHED);
158 }
159 
160 static loff_t usbdev_lseek(struct file *file, loff_t offset, int orig)
161 {
162 	loff_t ret;
163 
164 	mutex_lock(&file_inode(file)->i_mutex);
165 
166 	switch (orig) {
167 	case 0:
168 		file->f_pos = offset;
169 		ret = file->f_pos;
170 		break;
171 	case 1:
172 		file->f_pos += offset;
173 		ret = file->f_pos;
174 		break;
175 	case 2:
176 	default:
177 		ret = -EINVAL;
178 	}
179 
180 	mutex_unlock(&file_inode(file)->i_mutex);
181 	return ret;
182 }
183 
184 static ssize_t usbdev_read(struct file *file, char __user *buf, size_t nbytes,
185 			   loff_t *ppos)
186 {
187 	struct dev_state *ps = file->private_data;
188 	struct usb_device *dev = ps->dev;
189 	ssize_t ret = 0;
190 	unsigned len;
191 	loff_t pos;
192 	int i;
193 
194 	pos = *ppos;
195 	usb_lock_device(dev);
196 	if (!connected(ps)) {
197 		ret = -ENODEV;
198 		goto err;
199 	} else if (pos < 0) {
200 		ret = -EINVAL;
201 		goto err;
202 	}
203 
204 	if (pos < sizeof(struct usb_device_descriptor)) {
205 		/* 18 bytes - fits on the stack */
206 		struct usb_device_descriptor temp_desc;
207 
208 		memcpy(&temp_desc, &dev->descriptor, sizeof(dev->descriptor));
209 		le16_to_cpus(&temp_desc.bcdUSB);
210 		le16_to_cpus(&temp_desc.idVendor);
211 		le16_to_cpus(&temp_desc.idProduct);
212 		le16_to_cpus(&temp_desc.bcdDevice);
213 
214 		len = sizeof(struct usb_device_descriptor) - pos;
215 		if (len > nbytes)
216 			len = nbytes;
217 		if (copy_to_user(buf, ((char *)&temp_desc) + pos, len)) {
218 			ret = -EFAULT;
219 			goto err;
220 		}
221 
222 		*ppos += len;
223 		buf += len;
224 		nbytes -= len;
225 		ret += len;
226 	}
227 
228 	pos = sizeof(struct usb_device_descriptor);
229 	for (i = 0; nbytes && i < dev->descriptor.bNumConfigurations; i++) {
230 		struct usb_config_descriptor *config =
231 			(struct usb_config_descriptor *)dev->rawdescriptors[i];
232 		unsigned int length = le16_to_cpu(config->wTotalLength);
233 
234 		if (*ppos < pos + length) {
235 
236 			/* The descriptor may claim to be longer than it
237 			 * really is.  Here is the actual allocated length. */
238 			unsigned alloclen =
239 				le16_to_cpu(dev->config[i].desc.wTotalLength);
240 
241 			len = length - (*ppos - pos);
242 			if (len > nbytes)
243 				len = nbytes;
244 
245 			/* Simply don't write (skip over) unallocated parts */
246 			if (alloclen > (*ppos - pos)) {
247 				alloclen -= (*ppos - pos);
248 				if (copy_to_user(buf,
249 				    dev->rawdescriptors[i] + (*ppos - pos),
250 				    min(len, alloclen))) {
251 					ret = -EFAULT;
252 					goto err;
253 				}
254 			}
255 
256 			*ppos += len;
257 			buf += len;
258 			nbytes -= len;
259 			ret += len;
260 		}
261 
262 		pos += length;
263 	}
264 
265 err:
266 	usb_unlock_device(dev);
267 	return ret;
268 }
269 
270 /*
271  * async list handling
272  */
273 
274 static struct async *alloc_async(unsigned int numisoframes)
275 {
276 	struct async *as;
277 
278 	as = kzalloc(sizeof(struct async), GFP_KERNEL);
279 	if (!as)
280 		return NULL;
281 	as->urb = usb_alloc_urb(numisoframes, GFP_KERNEL);
282 	if (!as->urb) {
283 		kfree(as);
284 		return NULL;
285 	}
286 	return as;
287 }
288 
289 static void free_async(struct async *as)
290 {
291 	int i;
292 
293 	put_pid(as->pid);
294 	if (as->cred)
295 		put_cred(as->cred);
296 	for (i = 0; i < as->urb->num_sgs; i++) {
297 		if (sg_page(&as->urb->sg[i]))
298 			kfree(sg_virt(&as->urb->sg[i]));
299 	}
300 	kfree(as->urb->sg);
301 	kfree(as->urb->transfer_buffer);
302 	kfree(as->urb->setup_packet);
303 	usb_free_urb(as->urb);
304 	usbfs_decrease_memory_usage(as->mem_usage);
305 	kfree(as);
306 }
307 
308 static void async_newpending(struct async *as)
309 {
310 	struct dev_state *ps = as->ps;
311 	unsigned long flags;
312 
313 	spin_lock_irqsave(&ps->lock, flags);
314 	list_add_tail(&as->asynclist, &ps->async_pending);
315 	spin_unlock_irqrestore(&ps->lock, flags);
316 }
317 
318 static void async_removepending(struct async *as)
319 {
320 	struct dev_state *ps = as->ps;
321 	unsigned long flags;
322 
323 	spin_lock_irqsave(&ps->lock, flags);
324 	list_del_init(&as->asynclist);
325 	spin_unlock_irqrestore(&ps->lock, flags);
326 }
327 
328 static struct async *async_getcompleted(struct dev_state *ps)
329 {
330 	unsigned long flags;
331 	struct async *as = NULL;
332 
333 	spin_lock_irqsave(&ps->lock, flags);
334 	if (!list_empty(&ps->async_completed)) {
335 		as = list_entry(ps->async_completed.next, struct async,
336 				asynclist);
337 		list_del_init(&as->asynclist);
338 	}
339 	spin_unlock_irqrestore(&ps->lock, flags);
340 	return as;
341 }
342 
343 static struct async *async_getpending(struct dev_state *ps,
344 					     void __user *userurb)
345 {
346 	struct async *as;
347 
348 	list_for_each_entry(as, &ps->async_pending, asynclist)
349 		if (as->userurb == userurb) {
350 			list_del_init(&as->asynclist);
351 			return as;
352 		}
353 
354 	return NULL;
355 }
356 
357 static void snoop_urb(struct usb_device *udev,
358 		void __user *userurb, int pipe, unsigned length,
359 		int timeout_or_status, enum snoop_when when,
360 		unsigned char *data, unsigned data_len)
361 {
362 	static const char *types[] = {"isoc", "int", "ctrl", "bulk"};
363 	static const char *dirs[] = {"out", "in"};
364 	int ep;
365 	const char *t, *d;
366 
367 	if (!usbfs_snoop)
368 		return;
369 
370 	ep = usb_pipeendpoint(pipe);
371 	t = types[usb_pipetype(pipe)];
372 	d = dirs[!!usb_pipein(pipe)];
373 
374 	if (userurb) {		/* Async */
375 		if (when == SUBMIT)
376 			dev_info(&udev->dev, "userurb %p, ep%d %s-%s, "
377 					"length %u\n",
378 					userurb, ep, t, d, length);
379 		else
380 			dev_info(&udev->dev, "userurb %p, ep%d %s-%s, "
381 					"actual_length %u status %d\n",
382 					userurb, ep, t, d, length,
383 					timeout_or_status);
384 	} else {
385 		if (when == SUBMIT)
386 			dev_info(&udev->dev, "ep%d %s-%s, length %u, "
387 					"timeout %d\n",
388 					ep, t, d, length, timeout_or_status);
389 		else
390 			dev_info(&udev->dev, "ep%d %s-%s, actual_length %u, "
391 					"status %d\n",
392 					ep, t, d, length, timeout_or_status);
393 	}
394 
395 	if (data && data_len > 0) {
396 		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
397 			data, data_len, 1);
398 	}
399 }
400 
401 static void snoop_urb_data(struct urb *urb, unsigned len)
402 {
403 	int i, size;
404 
405 	if (!usbfs_snoop)
406 		return;
407 
408 	if (urb->num_sgs == 0) {
409 		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
410 			urb->transfer_buffer, len, 1);
411 		return;
412 	}
413 
414 	for (i = 0; i < urb->num_sgs && len; i++) {
415 		size = (len > USB_SG_SIZE) ? USB_SG_SIZE : len;
416 		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
417 			sg_virt(&urb->sg[i]), size, 1);
418 		len -= size;
419 	}
420 }
421 
422 static int copy_urb_data_to_user(u8 __user *userbuffer, struct urb *urb)
423 {
424 	unsigned i, len, size;
425 
426 	if (urb->number_of_packets > 0)		/* Isochronous */
427 		len = urb->transfer_buffer_length;
428 	else					/* Non-Isoc */
429 		len = urb->actual_length;
430 
431 	if (urb->num_sgs == 0) {
432 		if (copy_to_user(userbuffer, urb->transfer_buffer, len))
433 			return -EFAULT;
434 		return 0;
435 	}
436 
437 	for (i = 0; i < urb->num_sgs && len; i++) {
438 		size = (len > USB_SG_SIZE) ? USB_SG_SIZE : len;
439 		if (copy_to_user(userbuffer, sg_virt(&urb->sg[i]), size))
440 			return -EFAULT;
441 		userbuffer += size;
442 		len -= size;
443 	}
444 
445 	return 0;
446 }
447 
448 #define AS_CONTINUATION	1
449 #define AS_UNLINK	2
450 
451 static void cancel_bulk_urbs(struct dev_state *ps, unsigned bulk_addr)
452 __releases(ps->lock)
453 __acquires(ps->lock)
454 {
455 	struct urb *urb;
456 	struct async *as;
457 
458 	/* Mark all the pending URBs that match bulk_addr, up to but not
459 	 * including the first one without AS_CONTINUATION.  If such an
460 	 * URB is encountered then a new transfer has already started so
461 	 * the endpoint doesn't need to be disabled; otherwise it does.
462 	 */
463 	list_for_each_entry(as, &ps->async_pending, asynclist) {
464 		if (as->bulk_addr == bulk_addr) {
465 			if (as->bulk_status != AS_CONTINUATION)
466 				goto rescan;
467 			as->bulk_status = AS_UNLINK;
468 			as->bulk_addr = 0;
469 		}
470 	}
471 	ps->disabled_bulk_eps |= (1 << bulk_addr);
472 
473 	/* Now carefully unlink all the marked pending URBs */
474  rescan:
475 	list_for_each_entry(as, &ps->async_pending, asynclist) {
476 		if (as->bulk_status == AS_UNLINK) {
477 			as->bulk_status = 0;		/* Only once */
478 			urb = as->urb;
479 			usb_get_urb(urb);
480 			spin_unlock(&ps->lock);		/* Allow completions */
481 			usb_unlink_urb(urb);
482 			usb_put_urb(urb);
483 			spin_lock(&ps->lock);
484 			goto rescan;
485 		}
486 	}
487 }
488 
489 static void async_completed(struct urb *urb)
490 {
491 	struct async *as = urb->context;
492 	struct dev_state *ps = as->ps;
493 	struct siginfo sinfo;
494 	struct pid *pid = NULL;
495 	u32 secid = 0;
496 	const struct cred *cred = NULL;
497 	int signr;
498 
499 	spin_lock(&ps->lock);
500 	list_move_tail(&as->asynclist, &ps->async_completed);
501 	as->status = urb->status;
502 	signr = as->signr;
503 	if (signr) {
504 		sinfo.si_signo = as->signr;
505 		sinfo.si_errno = as->status;
506 		sinfo.si_code = SI_ASYNCIO;
507 		sinfo.si_addr = as->userurb;
508 		pid = get_pid(as->pid);
509 		cred = get_cred(as->cred);
510 		secid = as->secid;
511 	}
512 	snoop(&urb->dev->dev, "urb complete\n");
513 	snoop_urb(urb->dev, as->userurb, urb->pipe, urb->actual_length,
514 			as->status, COMPLETE, NULL, 0);
515 	if ((urb->transfer_flags & URB_DIR_MASK) == USB_DIR_IN)
516 		snoop_urb_data(urb, urb->actual_length);
517 
518 	if (as->status < 0 && as->bulk_addr && as->status != -ECONNRESET &&
519 			as->status != -ENOENT)
520 		cancel_bulk_urbs(ps, as->bulk_addr);
521 	spin_unlock(&ps->lock);
522 
523 	if (signr) {
524 		kill_pid_info_as_cred(sinfo.si_signo, &sinfo, pid, cred, secid);
525 		put_pid(pid);
526 		put_cred(cred);
527 	}
528 
529 	wake_up(&ps->wait);
530 }
531 
532 static void destroy_async(struct dev_state *ps, struct list_head *list)
533 {
534 	struct urb *urb;
535 	struct async *as;
536 	unsigned long flags;
537 
538 	spin_lock_irqsave(&ps->lock, flags);
539 	while (!list_empty(list)) {
540 		as = list_entry(list->next, struct async, asynclist);
541 		list_del_init(&as->asynclist);
542 		urb = as->urb;
543 		usb_get_urb(urb);
544 
545 		/* drop the spinlock so the completion handler can run */
546 		spin_unlock_irqrestore(&ps->lock, flags);
547 		usb_kill_urb(urb);
548 		usb_put_urb(urb);
549 		spin_lock_irqsave(&ps->lock, flags);
550 	}
551 	spin_unlock_irqrestore(&ps->lock, flags);
552 }
553 
554 static void destroy_async_on_interface(struct dev_state *ps,
555 				       unsigned int ifnum)
556 {
557 	struct list_head *p, *q, hitlist;
558 	unsigned long flags;
559 
560 	INIT_LIST_HEAD(&hitlist);
561 	spin_lock_irqsave(&ps->lock, flags);
562 	list_for_each_safe(p, q, &ps->async_pending)
563 		if (ifnum == list_entry(p, struct async, asynclist)->ifnum)
564 			list_move_tail(p, &hitlist);
565 	spin_unlock_irqrestore(&ps->lock, flags);
566 	destroy_async(ps, &hitlist);
567 }
568 
569 static void destroy_all_async(struct dev_state *ps)
570 {
571 	destroy_async(ps, &ps->async_pending);
572 }
573 
574 /*
575  * interface claims are made only at the request of user level code,
576  * which can also release them (explicitly or by closing files).
577  * they're also undone when devices disconnect.
578  */
579 
580 static int driver_probe(struct usb_interface *intf,
581 			const struct usb_device_id *id)
582 {
583 	return -ENODEV;
584 }
585 
586 static void driver_disconnect(struct usb_interface *intf)
587 {
588 	struct dev_state *ps = usb_get_intfdata(intf);
589 	unsigned int ifnum = intf->altsetting->desc.bInterfaceNumber;
590 
591 	if (!ps)
592 		return;
593 
594 	/* NOTE:  this relies on usbcore having canceled and completed
595 	 * all pending I/O requests; 2.6 does that.
596 	 */
597 
598 	if (likely(ifnum < 8*sizeof(ps->ifclaimed)))
599 		clear_bit(ifnum, &ps->ifclaimed);
600 	else
601 		dev_warn(&intf->dev, "interface number %u out of range\n",
602 			 ifnum);
603 
604 	usb_set_intfdata(intf, NULL);
605 
606 	/* force async requests to complete */
607 	destroy_async_on_interface(ps, ifnum);
608 }
609 
610 /* The following routines are merely placeholders.  There is no way
611  * to inform a user task about suspend or resumes.
612  */
613 static int driver_suspend(struct usb_interface *intf, pm_message_t msg)
614 {
615 	return 0;
616 }
617 
618 static int driver_resume(struct usb_interface *intf)
619 {
620 	return 0;
621 }
622 
623 struct usb_driver usbfs_driver = {
624 	.name =		"usbfs",
625 	.probe =	driver_probe,
626 	.disconnect =	driver_disconnect,
627 	.suspend =	driver_suspend,
628 	.resume =	driver_resume,
629 };
630 
631 static int claimintf(struct dev_state *ps, unsigned int ifnum)
632 {
633 	struct usb_device *dev = ps->dev;
634 	struct usb_interface *intf;
635 	int err;
636 
637 	if (ifnum >= 8*sizeof(ps->ifclaimed))
638 		return -EINVAL;
639 	/* already claimed */
640 	if (test_bit(ifnum, &ps->ifclaimed))
641 		return 0;
642 
643 	intf = usb_ifnum_to_if(dev, ifnum);
644 	if (!intf)
645 		err = -ENOENT;
646 	else
647 		err = usb_driver_claim_interface(&usbfs_driver, intf, ps);
648 	if (err == 0)
649 		set_bit(ifnum, &ps->ifclaimed);
650 	return err;
651 }
652 
653 static int releaseintf(struct dev_state *ps, unsigned int ifnum)
654 {
655 	struct usb_device *dev;
656 	struct usb_interface *intf;
657 	int err;
658 
659 	err = -EINVAL;
660 	if (ifnum >= 8*sizeof(ps->ifclaimed))
661 		return err;
662 	dev = ps->dev;
663 	intf = usb_ifnum_to_if(dev, ifnum);
664 	if (!intf)
665 		err = -ENOENT;
666 	else if (test_and_clear_bit(ifnum, &ps->ifclaimed)) {
667 		usb_driver_release_interface(&usbfs_driver, intf);
668 		err = 0;
669 	}
670 	return err;
671 }
672 
673 static int checkintf(struct dev_state *ps, unsigned int ifnum)
674 {
675 	if (ps->dev->state != USB_STATE_CONFIGURED)
676 		return -EHOSTUNREACH;
677 	if (ifnum >= 8*sizeof(ps->ifclaimed))
678 		return -EINVAL;
679 	if (test_bit(ifnum, &ps->ifclaimed))
680 		return 0;
681 	/* if not yet claimed, claim it for the driver */
682 	dev_warn(&ps->dev->dev, "usbfs: process %d (%s) did not claim "
683 		 "interface %u before use\n", task_pid_nr(current),
684 		 current->comm, ifnum);
685 	return claimintf(ps, ifnum);
686 }
687 
688 static int findintfep(struct usb_device *dev, unsigned int ep)
689 {
690 	unsigned int i, j, e;
691 	struct usb_interface *intf;
692 	struct usb_host_interface *alts;
693 	struct usb_endpoint_descriptor *endpt;
694 
695 	if (ep & ~(USB_DIR_IN|0xf))
696 		return -EINVAL;
697 	if (!dev->actconfig)
698 		return -ESRCH;
699 	for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
700 		intf = dev->actconfig->interface[i];
701 		for (j = 0; j < intf->num_altsetting; j++) {
702 			alts = &intf->altsetting[j];
703 			for (e = 0; e < alts->desc.bNumEndpoints; e++) {
704 				endpt = &alts->endpoint[e].desc;
705 				if (endpt->bEndpointAddress == ep)
706 					return alts->desc.bInterfaceNumber;
707 			}
708 		}
709 	}
710 	return -ENOENT;
711 }
712 
713 static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype,
714 			   unsigned int request, unsigned int index)
715 {
716 	int ret = 0;
717 	struct usb_host_interface *alt_setting;
718 
719 	if (ps->dev->state != USB_STATE_UNAUTHENTICATED
720 	 && ps->dev->state != USB_STATE_ADDRESS
721 	 && ps->dev->state != USB_STATE_CONFIGURED)
722 		return -EHOSTUNREACH;
723 	if (USB_TYPE_VENDOR == (USB_TYPE_MASK & requesttype))
724 		return 0;
725 
726 	/*
727 	 * check for the special corner case 'get_device_id' in the printer
728 	 * class specification, which we always want to allow as it is used
729 	 * to query things like ink level, etc.
730 	 */
731 	if (requesttype == 0xa1 && request == 0) {
732 		alt_setting = usb_find_alt_setting(ps->dev->actconfig,
733 						   index >> 8, index & 0xff);
734 		if (alt_setting
735 		 && alt_setting->desc.bInterfaceClass == USB_CLASS_PRINTER)
736 			return 0;
737 	}
738 
739 	index &= 0xff;
740 	switch (requesttype & USB_RECIP_MASK) {
741 	case USB_RECIP_ENDPOINT:
742 		if ((index & ~USB_DIR_IN) == 0)
743 			return 0;
744 		ret = findintfep(ps->dev, index);
745 		if (ret < 0) {
746 			/*
747 			 * Some not fully compliant Win apps seem to get
748 			 * index wrong and have the endpoint number here
749 			 * rather than the endpoint address (with the
750 			 * correct direction). Win does let this through,
751 			 * so we'll not reject it here but leave it to
752 			 * the device to not break KVM. But we warn.
753 			 */
754 			ret = findintfep(ps->dev, index ^ 0x80);
755 			if (ret >= 0)
756 				dev_info(&ps->dev->dev,
757 					"%s: process %i (%s) requesting ep %02x but needs %02x\n",
758 					__func__, task_pid_nr(current),
759 					current->comm, index, index ^ 0x80);
760 		}
761 		if (ret >= 0)
762 			ret = checkintf(ps, ret);
763 		break;
764 
765 	case USB_RECIP_INTERFACE:
766 		ret = checkintf(ps, index);
767 		break;
768 	}
769 	return ret;
770 }
771 
772 static int match_devt(struct device *dev, void *data)
773 {
774 	return dev->devt == (dev_t) (unsigned long) data;
775 }
776 
777 static struct usb_device *usbdev_lookup_by_devt(dev_t devt)
778 {
779 	struct device *dev;
780 
781 	dev = bus_find_device(&usb_bus_type, NULL,
782 			      (void *) (unsigned long) devt, match_devt);
783 	if (!dev)
784 		return NULL;
785 	return container_of(dev, struct usb_device, dev);
786 }
787 
788 /*
789  * file operations
790  */
791 static int usbdev_open(struct inode *inode, struct file *file)
792 {
793 	struct usb_device *dev = NULL;
794 	struct dev_state *ps;
795 	int ret;
796 
797 	ret = -ENOMEM;
798 	ps = kmalloc(sizeof(struct dev_state), GFP_KERNEL);
799 	if (!ps)
800 		goto out_free_ps;
801 
802 	ret = -ENODEV;
803 
804 	/* Protect against simultaneous removal or release */
805 	mutex_lock(&usbfs_mutex);
806 
807 	/* usbdev device-node */
808 	if (imajor(inode) == USB_DEVICE_MAJOR)
809 		dev = usbdev_lookup_by_devt(inode->i_rdev);
810 
811 	mutex_unlock(&usbfs_mutex);
812 
813 	if (!dev)
814 		goto out_free_ps;
815 
816 	usb_lock_device(dev);
817 	if (dev->state == USB_STATE_NOTATTACHED)
818 		goto out_unlock_device;
819 
820 	ret = usb_autoresume_device(dev);
821 	if (ret)
822 		goto out_unlock_device;
823 
824 	ps->dev = dev;
825 	ps->file = file;
826 	spin_lock_init(&ps->lock);
827 	INIT_LIST_HEAD(&ps->list);
828 	INIT_LIST_HEAD(&ps->async_pending);
829 	INIT_LIST_HEAD(&ps->async_completed);
830 	init_waitqueue_head(&ps->wait);
831 	ps->discsignr = 0;
832 	ps->disc_pid = get_pid(task_pid(current));
833 	ps->cred = get_current_cred();
834 	ps->disccontext = NULL;
835 	ps->ifclaimed = 0;
836 	security_task_getsecid(current, &ps->secid);
837 	smp_wmb();
838 	list_add_tail(&ps->list, &dev->filelist);
839 	file->private_data = ps;
840 	usb_unlock_device(dev);
841 	snoop(&dev->dev, "opened by process %d: %s\n", task_pid_nr(current),
842 			current->comm);
843 	return ret;
844 
845  out_unlock_device:
846 	usb_unlock_device(dev);
847 	usb_put_dev(dev);
848  out_free_ps:
849 	kfree(ps);
850 	return ret;
851 }
852 
853 static int usbdev_release(struct inode *inode, struct file *file)
854 {
855 	struct dev_state *ps = file->private_data;
856 	struct usb_device *dev = ps->dev;
857 	unsigned int ifnum;
858 	struct async *as;
859 
860 	usb_lock_device(dev);
861 	usb_hub_release_all_ports(dev, ps);
862 
863 	list_del_init(&ps->list);
864 
865 	for (ifnum = 0; ps->ifclaimed && ifnum < 8*sizeof(ps->ifclaimed);
866 			ifnum++) {
867 		if (test_bit(ifnum, &ps->ifclaimed))
868 			releaseintf(ps, ifnum);
869 	}
870 	destroy_all_async(ps);
871 	usb_autosuspend_device(dev);
872 	usb_unlock_device(dev);
873 	usb_put_dev(dev);
874 	put_pid(ps->disc_pid);
875 	put_cred(ps->cred);
876 
877 	as = async_getcompleted(ps);
878 	while (as) {
879 		free_async(as);
880 		as = async_getcompleted(ps);
881 	}
882 	kfree(ps);
883 	return 0;
884 }
885 
886 static int proc_control(struct dev_state *ps, void __user *arg)
887 {
888 	struct usb_device *dev = ps->dev;
889 	struct usbdevfs_ctrltransfer ctrl;
890 	unsigned int tmo;
891 	unsigned char *tbuf;
892 	unsigned wLength;
893 	int i, pipe, ret;
894 
895 	if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
896 		return -EFAULT;
897 	ret = check_ctrlrecip(ps, ctrl.bRequestType, ctrl.bRequest,
898 			      ctrl.wIndex);
899 	if (ret)
900 		return ret;
901 	wLength = ctrl.wLength;		/* To suppress 64k PAGE_SIZE warning */
902 	if (wLength > PAGE_SIZE)
903 		return -EINVAL;
904 	ret = usbfs_increase_memory_usage(PAGE_SIZE + sizeof(struct urb) +
905 			sizeof(struct usb_ctrlrequest));
906 	if (ret)
907 		return ret;
908 	tbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
909 	if (!tbuf) {
910 		ret = -ENOMEM;
911 		goto done;
912 	}
913 	tmo = ctrl.timeout;
914 	snoop(&dev->dev, "control urb: bRequestType=%02x "
915 		"bRequest=%02x wValue=%04x "
916 		"wIndex=%04x wLength=%04x\n",
917 		ctrl.bRequestType, ctrl.bRequest,
918 		__le16_to_cpup(&ctrl.wValue),
919 		__le16_to_cpup(&ctrl.wIndex),
920 		__le16_to_cpup(&ctrl.wLength));
921 	if (ctrl.bRequestType & 0x80) {
922 		if (ctrl.wLength && !access_ok(VERIFY_WRITE, ctrl.data,
923 					       ctrl.wLength)) {
924 			ret = -EINVAL;
925 			goto done;
926 		}
927 		pipe = usb_rcvctrlpipe(dev, 0);
928 		snoop_urb(dev, NULL, pipe, ctrl.wLength, tmo, SUBMIT, NULL, 0);
929 
930 		usb_unlock_device(dev);
931 		i = usb_control_msg(dev, pipe, ctrl.bRequest,
932 				    ctrl.bRequestType, ctrl.wValue, ctrl.wIndex,
933 				    tbuf, ctrl.wLength, tmo);
934 		usb_lock_device(dev);
935 		snoop_urb(dev, NULL, pipe, max(i, 0), min(i, 0), COMPLETE,
936 			  tbuf, max(i, 0));
937 		if ((i > 0) && ctrl.wLength) {
938 			if (copy_to_user(ctrl.data, tbuf, i)) {
939 				ret = -EFAULT;
940 				goto done;
941 			}
942 		}
943 	} else {
944 		if (ctrl.wLength) {
945 			if (copy_from_user(tbuf, ctrl.data, ctrl.wLength)) {
946 				ret = -EFAULT;
947 				goto done;
948 			}
949 		}
950 		pipe = usb_sndctrlpipe(dev, 0);
951 		snoop_urb(dev, NULL, pipe, ctrl.wLength, tmo, SUBMIT,
952 			tbuf, ctrl.wLength);
953 
954 		usb_unlock_device(dev);
955 		i = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), ctrl.bRequest,
956 				    ctrl.bRequestType, ctrl.wValue, ctrl.wIndex,
957 				    tbuf, ctrl.wLength, tmo);
958 		usb_lock_device(dev);
959 		snoop_urb(dev, NULL, pipe, max(i, 0), min(i, 0), COMPLETE, NULL, 0);
960 	}
961 	if (i < 0 && i != -EPIPE) {
962 		dev_printk(KERN_DEBUG, &dev->dev, "usbfs: USBDEVFS_CONTROL "
963 			   "failed cmd %s rqt %u rq %u len %u ret %d\n",
964 			   current->comm, ctrl.bRequestType, ctrl.bRequest,
965 			   ctrl.wLength, i);
966 	}
967 	ret = i;
968  done:
969 	free_page((unsigned long) tbuf);
970 	usbfs_decrease_memory_usage(PAGE_SIZE + sizeof(struct urb) +
971 			sizeof(struct usb_ctrlrequest));
972 	return ret;
973 }
974 
975 static int proc_bulk(struct dev_state *ps, void __user *arg)
976 {
977 	struct usb_device *dev = ps->dev;
978 	struct usbdevfs_bulktransfer bulk;
979 	unsigned int tmo, len1, pipe;
980 	int len2;
981 	unsigned char *tbuf;
982 	int i, ret;
983 
984 	if (copy_from_user(&bulk, arg, sizeof(bulk)))
985 		return -EFAULT;
986 	ret = findintfep(ps->dev, bulk.ep);
987 	if (ret < 0)
988 		return ret;
989 	ret = checkintf(ps, ret);
990 	if (ret)
991 		return ret;
992 	if (bulk.ep & USB_DIR_IN)
993 		pipe = usb_rcvbulkpipe(dev, bulk.ep & 0x7f);
994 	else
995 		pipe = usb_sndbulkpipe(dev, bulk.ep & 0x7f);
996 	if (!usb_maxpacket(dev, pipe, !(bulk.ep & USB_DIR_IN)))
997 		return -EINVAL;
998 	len1 = bulk.len;
999 	if (len1 >= USBFS_XFER_MAX)
1000 		return -EINVAL;
1001 	ret = usbfs_increase_memory_usage(len1 + sizeof(struct urb));
1002 	if (ret)
1003 		return ret;
1004 	if (!(tbuf = kmalloc(len1, GFP_KERNEL))) {
1005 		ret = -ENOMEM;
1006 		goto done;
1007 	}
1008 	tmo = bulk.timeout;
1009 	if (bulk.ep & 0x80) {
1010 		if (len1 && !access_ok(VERIFY_WRITE, bulk.data, len1)) {
1011 			ret = -EINVAL;
1012 			goto done;
1013 		}
1014 		snoop_urb(dev, NULL, pipe, len1, tmo, SUBMIT, NULL, 0);
1015 
1016 		usb_unlock_device(dev);
1017 		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
1018 		usb_lock_device(dev);
1019 		snoop_urb(dev, NULL, pipe, len2, i, COMPLETE, tbuf, len2);
1020 
1021 		if (!i && len2) {
1022 			if (copy_to_user(bulk.data, tbuf, len2)) {
1023 				ret = -EFAULT;
1024 				goto done;
1025 			}
1026 		}
1027 	} else {
1028 		if (len1) {
1029 			if (copy_from_user(tbuf, bulk.data, len1)) {
1030 				ret = -EFAULT;
1031 				goto done;
1032 			}
1033 		}
1034 		snoop_urb(dev, NULL, pipe, len1, tmo, SUBMIT, tbuf, len1);
1035 
1036 		usb_unlock_device(dev);
1037 		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
1038 		usb_lock_device(dev);
1039 		snoop_urb(dev, NULL, pipe, len2, i, COMPLETE, NULL, 0);
1040 	}
1041 	ret = (i < 0 ? i : len2);
1042  done:
1043 	kfree(tbuf);
1044 	usbfs_decrease_memory_usage(len1 + sizeof(struct urb));
1045 	return ret;
1046 }
1047 
1048 static int proc_resetep(struct dev_state *ps, void __user *arg)
1049 {
1050 	unsigned int ep;
1051 	int ret;
1052 
1053 	if (get_user(ep, (unsigned int __user *)arg))
1054 		return -EFAULT;
1055 	ret = findintfep(ps->dev, ep);
1056 	if (ret < 0)
1057 		return ret;
1058 	ret = checkintf(ps, ret);
1059 	if (ret)
1060 		return ret;
1061 	usb_reset_endpoint(ps->dev, ep);
1062 	return 0;
1063 }
1064 
1065 static int proc_clearhalt(struct dev_state *ps, void __user *arg)
1066 {
1067 	unsigned int ep;
1068 	int pipe;
1069 	int ret;
1070 
1071 	if (get_user(ep, (unsigned int __user *)arg))
1072 		return -EFAULT;
1073 	ret = findintfep(ps->dev, ep);
1074 	if (ret < 0)
1075 		return ret;
1076 	ret = checkintf(ps, ret);
1077 	if (ret)
1078 		return ret;
1079 	if (ep & USB_DIR_IN)
1080 		pipe = usb_rcvbulkpipe(ps->dev, ep & 0x7f);
1081 	else
1082 		pipe = usb_sndbulkpipe(ps->dev, ep & 0x7f);
1083 
1084 	return usb_clear_halt(ps->dev, pipe);
1085 }
1086 
1087 static int proc_getdriver(struct dev_state *ps, void __user *arg)
1088 {
1089 	struct usbdevfs_getdriver gd;
1090 	struct usb_interface *intf;
1091 	int ret;
1092 
1093 	if (copy_from_user(&gd, arg, sizeof(gd)))
1094 		return -EFAULT;
1095 	intf = usb_ifnum_to_if(ps->dev, gd.interface);
1096 	if (!intf || !intf->dev.driver)
1097 		ret = -ENODATA;
1098 	else {
1099 		strlcpy(gd.driver, intf->dev.driver->name,
1100 				sizeof(gd.driver));
1101 		ret = (copy_to_user(arg, &gd, sizeof(gd)) ? -EFAULT : 0);
1102 	}
1103 	return ret;
1104 }
1105 
1106 static int proc_connectinfo(struct dev_state *ps, void __user *arg)
1107 {
1108 	struct usbdevfs_connectinfo ci = {
1109 		.devnum = ps->dev->devnum,
1110 		.slow = ps->dev->speed == USB_SPEED_LOW
1111 	};
1112 
1113 	if (copy_to_user(arg, &ci, sizeof(ci)))
1114 		return -EFAULT;
1115 	return 0;
1116 }
1117 
1118 static int proc_resetdevice(struct dev_state *ps)
1119 {
1120 	return usb_reset_device(ps->dev);
1121 }
1122 
1123 static int proc_setintf(struct dev_state *ps, void __user *arg)
1124 {
1125 	struct usbdevfs_setinterface setintf;
1126 	int ret;
1127 
1128 	if (copy_from_user(&setintf, arg, sizeof(setintf)))
1129 		return -EFAULT;
1130 	if ((ret = checkintf(ps, setintf.interface)))
1131 		return ret;
1132 	return usb_set_interface(ps->dev, setintf.interface,
1133 			setintf.altsetting);
1134 }
1135 
1136 static int proc_setconfig(struct dev_state *ps, void __user *arg)
1137 {
1138 	int u;
1139 	int status = 0;
1140 	struct usb_host_config *actconfig;
1141 
1142 	if (get_user(u, (int __user *)arg))
1143 		return -EFAULT;
1144 
1145 	actconfig = ps->dev->actconfig;
1146 
1147 	/* Don't touch the device if any interfaces are claimed.
1148 	 * It could interfere with other drivers' operations, and if
1149 	 * an interface is claimed by usbfs it could easily deadlock.
1150 	 */
1151 	if (actconfig) {
1152 		int i;
1153 
1154 		for (i = 0; i < actconfig->desc.bNumInterfaces; ++i) {
1155 			if (usb_interface_claimed(actconfig->interface[i])) {
1156 				dev_warn(&ps->dev->dev,
1157 					"usbfs: interface %d claimed by %s "
1158 					"while '%s' sets config #%d\n",
1159 					actconfig->interface[i]
1160 						->cur_altsetting
1161 						->desc.bInterfaceNumber,
1162 					actconfig->interface[i]
1163 						->dev.driver->name,
1164 					current->comm, u);
1165 				status = -EBUSY;
1166 				break;
1167 			}
1168 		}
1169 	}
1170 
1171 	/* SET_CONFIGURATION is often abused as a "cheap" driver reset,
1172 	 * so avoid usb_set_configuration()'s kick to sysfs
1173 	 */
1174 	if (status == 0) {
1175 		if (actconfig && actconfig->desc.bConfigurationValue == u)
1176 			status = usb_reset_configuration(ps->dev);
1177 		else
1178 			status = usb_set_configuration(ps->dev, u);
1179 	}
1180 
1181 	return status;
1182 }
1183 
1184 static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
1185 			struct usbdevfs_iso_packet_desc __user *iso_frame_desc,
1186 			void __user *arg)
1187 {
1188 	struct usbdevfs_iso_packet_desc *isopkt = NULL;
1189 	struct usb_host_endpoint *ep;
1190 	struct async *as = NULL;
1191 	struct usb_ctrlrequest *dr = NULL;
1192 	unsigned int u, totlen, isofrmlen;
1193 	int i, ret, is_in, num_sgs = 0, ifnum = -1;
1194 	void *buf;
1195 
1196 	if (uurb->flags & ~(USBDEVFS_URB_ISO_ASAP |
1197 				USBDEVFS_URB_SHORT_NOT_OK |
1198 				USBDEVFS_URB_BULK_CONTINUATION |
1199 				USBDEVFS_URB_NO_FSBR |
1200 				USBDEVFS_URB_ZERO_PACKET |
1201 				USBDEVFS_URB_NO_INTERRUPT))
1202 		return -EINVAL;
1203 	if (uurb->buffer_length > 0 && !uurb->buffer)
1204 		return -EINVAL;
1205 	if (!(uurb->type == USBDEVFS_URB_TYPE_CONTROL &&
1206 	    (uurb->endpoint & ~USB_ENDPOINT_DIR_MASK) == 0)) {
1207 		ifnum = findintfep(ps->dev, uurb->endpoint);
1208 		if (ifnum < 0)
1209 			return ifnum;
1210 		ret = checkintf(ps, ifnum);
1211 		if (ret)
1212 			return ret;
1213 	}
1214 	if ((uurb->endpoint & USB_ENDPOINT_DIR_MASK) != 0) {
1215 		is_in = 1;
1216 		ep = ps->dev->ep_in[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
1217 	} else {
1218 		is_in = 0;
1219 		ep = ps->dev->ep_out[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
1220 	}
1221 	if (!ep)
1222 		return -ENOENT;
1223 
1224 	u = 0;
1225 	switch(uurb->type) {
1226 	case USBDEVFS_URB_TYPE_CONTROL:
1227 		if (!usb_endpoint_xfer_control(&ep->desc))
1228 			return -EINVAL;
1229 		/* min 8 byte setup packet */
1230 		if (uurb->buffer_length < 8)
1231 			return -EINVAL;
1232 		dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
1233 		if (!dr)
1234 			return -ENOMEM;
1235 		if (copy_from_user(dr, uurb->buffer, 8)) {
1236 			ret = -EFAULT;
1237 			goto error;
1238 		}
1239 		if (uurb->buffer_length < (le16_to_cpup(&dr->wLength) + 8)) {
1240 			ret = -EINVAL;
1241 			goto error;
1242 		}
1243 		ret = check_ctrlrecip(ps, dr->bRequestType, dr->bRequest,
1244 				      le16_to_cpup(&dr->wIndex));
1245 		if (ret)
1246 			goto error;
1247 		uurb->number_of_packets = 0;
1248 		uurb->buffer_length = le16_to_cpup(&dr->wLength);
1249 		uurb->buffer += 8;
1250 		if ((dr->bRequestType & USB_DIR_IN) && uurb->buffer_length) {
1251 			is_in = 1;
1252 			uurb->endpoint |= USB_DIR_IN;
1253 		} else {
1254 			is_in = 0;
1255 			uurb->endpoint &= ~USB_DIR_IN;
1256 		}
1257 		snoop(&ps->dev->dev, "control urb: bRequestType=%02x "
1258 			"bRequest=%02x wValue=%04x "
1259 			"wIndex=%04x wLength=%04x\n",
1260 			dr->bRequestType, dr->bRequest,
1261 			__le16_to_cpup(&dr->wValue),
1262 			__le16_to_cpup(&dr->wIndex),
1263 			__le16_to_cpup(&dr->wLength));
1264 		u = sizeof(struct usb_ctrlrequest);
1265 		break;
1266 
1267 	case USBDEVFS_URB_TYPE_BULK:
1268 		switch (usb_endpoint_type(&ep->desc)) {
1269 		case USB_ENDPOINT_XFER_CONTROL:
1270 		case USB_ENDPOINT_XFER_ISOC:
1271 			return -EINVAL;
1272 		case USB_ENDPOINT_XFER_INT:
1273 			/* allow single-shot interrupt transfers */
1274 			uurb->type = USBDEVFS_URB_TYPE_INTERRUPT;
1275 			goto interrupt_urb;
1276 		}
1277 		uurb->number_of_packets = 0;
1278 		num_sgs = DIV_ROUND_UP(uurb->buffer_length, USB_SG_SIZE);
1279 		if (num_sgs == 1 || num_sgs > ps->dev->bus->sg_tablesize)
1280 			num_sgs = 0;
1281 		break;
1282 
1283 	case USBDEVFS_URB_TYPE_INTERRUPT:
1284 		if (!usb_endpoint_xfer_int(&ep->desc))
1285 			return -EINVAL;
1286  interrupt_urb:
1287 		uurb->number_of_packets = 0;
1288 		break;
1289 
1290 	case USBDEVFS_URB_TYPE_ISO:
1291 		/* arbitrary limit */
1292 		if (uurb->number_of_packets < 1 ||
1293 		    uurb->number_of_packets > 128)
1294 			return -EINVAL;
1295 		if (!usb_endpoint_xfer_isoc(&ep->desc))
1296 			return -EINVAL;
1297 		isofrmlen = sizeof(struct usbdevfs_iso_packet_desc) *
1298 				   uurb->number_of_packets;
1299 		if (!(isopkt = kmalloc(isofrmlen, GFP_KERNEL)))
1300 			return -ENOMEM;
1301 		if (copy_from_user(isopkt, iso_frame_desc, isofrmlen)) {
1302 			ret = -EFAULT;
1303 			goto error;
1304 		}
1305 		for (totlen = u = 0; u < uurb->number_of_packets; u++) {
1306 			/*
1307 			 * arbitrary limit need for USB 3.0
1308 			 * bMaxBurst (0~15 allowed, 1~16 packets)
1309 			 * bmAttributes (bit 1:0, mult 0~2, 1~3 packets)
1310 			 * sizemax: 1024 * 16 * 3 = 49152
1311 			 */
1312 			if (isopkt[u].length > 49152) {
1313 				ret = -EINVAL;
1314 				goto error;
1315 			}
1316 			totlen += isopkt[u].length;
1317 		}
1318 		u *= sizeof(struct usb_iso_packet_descriptor);
1319 		uurb->buffer_length = totlen;
1320 		break;
1321 
1322 	default:
1323 		return -EINVAL;
1324 	}
1325 
1326 	if (uurb->buffer_length >= USBFS_XFER_MAX) {
1327 		ret = -EINVAL;
1328 		goto error;
1329 	}
1330 	if (uurb->buffer_length > 0 &&
1331 			!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ,
1332 				uurb->buffer, uurb->buffer_length)) {
1333 		ret = -EFAULT;
1334 		goto error;
1335 	}
1336 	as = alloc_async(uurb->number_of_packets);
1337 	if (!as) {
1338 		ret = -ENOMEM;
1339 		goto error;
1340 	}
1341 
1342 	u += sizeof(struct async) + sizeof(struct urb) + uurb->buffer_length +
1343 	     num_sgs * sizeof(struct scatterlist);
1344 	ret = usbfs_increase_memory_usage(u);
1345 	if (ret)
1346 		goto error;
1347 	as->mem_usage = u;
1348 
1349 	if (num_sgs) {
1350 		as->urb->sg = kmalloc(num_sgs * sizeof(struct scatterlist),
1351 				      GFP_KERNEL);
1352 		if (!as->urb->sg) {
1353 			ret = -ENOMEM;
1354 			goto error;
1355 		}
1356 		as->urb->num_sgs = num_sgs;
1357 		sg_init_table(as->urb->sg, as->urb->num_sgs);
1358 
1359 		totlen = uurb->buffer_length;
1360 		for (i = 0; i < as->urb->num_sgs; i++) {
1361 			u = (totlen > USB_SG_SIZE) ? USB_SG_SIZE : totlen;
1362 			buf = kmalloc(u, GFP_KERNEL);
1363 			if (!buf) {
1364 				ret = -ENOMEM;
1365 				goto error;
1366 			}
1367 			sg_set_buf(&as->urb->sg[i], buf, u);
1368 
1369 			if (!is_in) {
1370 				if (copy_from_user(buf, uurb->buffer, u)) {
1371 					ret = -EFAULT;
1372 					goto error;
1373 				}
1374 				uurb->buffer += u;
1375 			}
1376 			totlen -= u;
1377 		}
1378 	} else if (uurb->buffer_length > 0) {
1379 		as->urb->transfer_buffer = kmalloc(uurb->buffer_length,
1380 				GFP_KERNEL);
1381 		if (!as->urb->transfer_buffer) {
1382 			ret = -ENOMEM;
1383 			goto error;
1384 		}
1385 
1386 		if (!is_in) {
1387 			if (copy_from_user(as->urb->transfer_buffer,
1388 					   uurb->buffer,
1389 					   uurb->buffer_length)) {
1390 				ret = -EFAULT;
1391 				goto error;
1392 			}
1393 		} else if (uurb->type == USBDEVFS_URB_TYPE_ISO) {
1394 			/*
1395 			 * Isochronous input data may end up being
1396 			 * discontiguous if some of the packets are short.
1397 			 * Clear the buffer so that the gaps don't leak
1398 			 * kernel data to userspace.
1399 			 */
1400 			memset(as->urb->transfer_buffer, 0,
1401 					uurb->buffer_length);
1402 		}
1403 	}
1404 	as->urb->dev = ps->dev;
1405 	as->urb->pipe = (uurb->type << 30) |
1406 			__create_pipe(ps->dev, uurb->endpoint & 0xf) |
1407 			(uurb->endpoint & USB_DIR_IN);
1408 
1409 	/* This tedious sequence is necessary because the URB_* flags
1410 	 * are internal to the kernel and subject to change, whereas
1411 	 * the USBDEVFS_URB_* flags are a user API and must not be changed.
1412 	 */
1413 	u = (is_in ? URB_DIR_IN : URB_DIR_OUT);
1414 	if (uurb->flags & USBDEVFS_URB_ISO_ASAP)
1415 		u |= URB_ISO_ASAP;
1416 	if (uurb->flags & USBDEVFS_URB_SHORT_NOT_OK)
1417 		u |= URB_SHORT_NOT_OK;
1418 	if (uurb->flags & USBDEVFS_URB_NO_FSBR)
1419 		u |= URB_NO_FSBR;
1420 	if (uurb->flags & USBDEVFS_URB_ZERO_PACKET)
1421 		u |= URB_ZERO_PACKET;
1422 	if (uurb->flags & USBDEVFS_URB_NO_INTERRUPT)
1423 		u |= URB_NO_INTERRUPT;
1424 	as->urb->transfer_flags = u;
1425 
1426 	as->urb->transfer_buffer_length = uurb->buffer_length;
1427 	as->urb->setup_packet = (unsigned char *)dr;
1428 	dr = NULL;
1429 	as->urb->start_frame = uurb->start_frame;
1430 	as->urb->number_of_packets = uurb->number_of_packets;
1431 	if (uurb->type == USBDEVFS_URB_TYPE_ISO ||
1432 			ps->dev->speed == USB_SPEED_HIGH)
1433 		as->urb->interval = 1 << min(15, ep->desc.bInterval - 1);
1434 	else
1435 		as->urb->interval = ep->desc.bInterval;
1436 	as->urb->context = as;
1437 	as->urb->complete = async_completed;
1438 	for (totlen = u = 0; u < uurb->number_of_packets; u++) {
1439 		as->urb->iso_frame_desc[u].offset = totlen;
1440 		as->urb->iso_frame_desc[u].length = isopkt[u].length;
1441 		totlen += isopkt[u].length;
1442 	}
1443 	kfree(isopkt);
1444 	isopkt = NULL;
1445 	as->ps = ps;
1446 	as->userurb = arg;
1447 	if (is_in && uurb->buffer_length > 0)
1448 		as->userbuffer = uurb->buffer;
1449 	else
1450 		as->userbuffer = NULL;
1451 	as->signr = uurb->signr;
1452 	as->ifnum = ifnum;
1453 	as->pid = get_pid(task_pid(current));
1454 	as->cred = get_current_cred();
1455 	security_task_getsecid(current, &as->secid);
1456 	snoop_urb(ps->dev, as->userurb, as->urb->pipe,
1457 			as->urb->transfer_buffer_length, 0, SUBMIT,
1458 			NULL, 0);
1459 	if (!is_in)
1460 		snoop_urb_data(as->urb, as->urb->transfer_buffer_length);
1461 
1462 	async_newpending(as);
1463 
1464 	if (usb_endpoint_xfer_bulk(&ep->desc)) {
1465 		spin_lock_irq(&ps->lock);
1466 
1467 		/* Not exactly the endpoint address; the direction bit is
1468 		 * shifted to the 0x10 position so that the value will be
1469 		 * between 0 and 31.
1470 		 */
1471 		as->bulk_addr = usb_endpoint_num(&ep->desc) |
1472 			((ep->desc.bEndpointAddress & USB_ENDPOINT_DIR_MASK)
1473 				>> 3);
1474 
1475 		/* If this bulk URB is the start of a new transfer, re-enable
1476 		 * the endpoint.  Otherwise mark it as a continuation URB.
1477 		 */
1478 		if (uurb->flags & USBDEVFS_URB_BULK_CONTINUATION)
1479 			as->bulk_status = AS_CONTINUATION;
1480 		else
1481 			ps->disabled_bulk_eps &= ~(1 << as->bulk_addr);
1482 
1483 		/* Don't accept continuation URBs if the endpoint is
1484 		 * disabled because of an earlier error.
1485 		 */
1486 		if (ps->disabled_bulk_eps & (1 << as->bulk_addr))
1487 			ret = -EREMOTEIO;
1488 		else
1489 			ret = usb_submit_urb(as->urb, GFP_ATOMIC);
1490 		spin_unlock_irq(&ps->lock);
1491 	} else {
1492 		ret = usb_submit_urb(as->urb, GFP_KERNEL);
1493 	}
1494 
1495 	if (ret) {
1496 		dev_printk(KERN_DEBUG, &ps->dev->dev,
1497 			   "usbfs: usb_submit_urb returned %d\n", ret);
1498 		snoop_urb(ps->dev, as->userurb, as->urb->pipe,
1499 				0, ret, COMPLETE, NULL, 0);
1500 		async_removepending(as);
1501 		goto error;
1502 	}
1503 	return 0;
1504 
1505  error:
1506 	kfree(isopkt);
1507 	kfree(dr);
1508 	if (as)
1509 		free_async(as);
1510 	return ret;
1511 }
1512 
1513 static int proc_submiturb(struct dev_state *ps, void __user *arg)
1514 {
1515 	struct usbdevfs_urb uurb;
1516 
1517 	if (copy_from_user(&uurb, arg, sizeof(uurb)))
1518 		return -EFAULT;
1519 
1520 	return proc_do_submiturb(ps, &uurb,
1521 			(((struct usbdevfs_urb __user *)arg)->iso_frame_desc),
1522 			arg);
1523 }
1524 
1525 static int proc_unlinkurb(struct dev_state *ps, void __user *arg)
1526 {
1527 	struct urb *urb;
1528 	struct async *as;
1529 	unsigned long flags;
1530 
1531 	spin_lock_irqsave(&ps->lock, flags);
1532 	as = async_getpending(ps, arg);
1533 	if (!as) {
1534 		spin_unlock_irqrestore(&ps->lock, flags);
1535 		return -EINVAL;
1536 	}
1537 
1538 	urb = as->urb;
1539 	usb_get_urb(urb);
1540 	spin_unlock_irqrestore(&ps->lock, flags);
1541 
1542 	usb_kill_urb(urb);
1543 	usb_put_urb(urb);
1544 
1545 	return 0;
1546 }
1547 
1548 static int processcompl(struct async *as, void __user * __user *arg)
1549 {
1550 	struct urb *urb = as->urb;
1551 	struct usbdevfs_urb __user *userurb = as->userurb;
1552 	void __user *addr = as->userurb;
1553 	unsigned int i;
1554 
1555 	if (as->userbuffer && urb->actual_length) {
1556 		if (copy_urb_data_to_user(as->userbuffer, urb))
1557 			goto err_out;
1558 	}
1559 	if (put_user(as->status, &userurb->status))
1560 		goto err_out;
1561 	if (put_user(urb->actual_length, &userurb->actual_length))
1562 		goto err_out;
1563 	if (put_user(urb->error_count, &userurb->error_count))
1564 		goto err_out;
1565 
1566 	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1567 		for (i = 0; i < urb->number_of_packets; i++) {
1568 			if (put_user(urb->iso_frame_desc[i].actual_length,
1569 				     &userurb->iso_frame_desc[i].actual_length))
1570 				goto err_out;
1571 			if (put_user(urb->iso_frame_desc[i].status,
1572 				     &userurb->iso_frame_desc[i].status))
1573 				goto err_out;
1574 		}
1575 	}
1576 
1577 	if (put_user(addr, (void __user * __user *)arg))
1578 		return -EFAULT;
1579 	return 0;
1580 
1581 err_out:
1582 	return -EFAULT;
1583 }
1584 
1585 static struct async *reap_as(struct dev_state *ps)
1586 {
1587 	DECLARE_WAITQUEUE(wait, current);
1588 	struct async *as = NULL;
1589 	struct usb_device *dev = ps->dev;
1590 
1591 	add_wait_queue(&ps->wait, &wait);
1592 	for (;;) {
1593 		__set_current_state(TASK_INTERRUPTIBLE);
1594 		as = async_getcompleted(ps);
1595 		if (as)
1596 			break;
1597 		if (signal_pending(current))
1598 			break;
1599 		usb_unlock_device(dev);
1600 		schedule();
1601 		usb_lock_device(dev);
1602 	}
1603 	remove_wait_queue(&ps->wait, &wait);
1604 	set_current_state(TASK_RUNNING);
1605 	return as;
1606 }
1607 
1608 static int proc_reapurb(struct dev_state *ps, void __user *arg)
1609 {
1610 	struct async *as = reap_as(ps);
1611 	if (as) {
1612 		int retval = processcompl(as, (void __user * __user *)arg);
1613 		free_async(as);
1614 		return retval;
1615 	}
1616 	if (signal_pending(current))
1617 		return -EINTR;
1618 	return -EIO;
1619 }
1620 
1621 static int proc_reapurbnonblock(struct dev_state *ps, void __user *arg)
1622 {
1623 	int retval;
1624 	struct async *as;
1625 
1626 	as = async_getcompleted(ps);
1627 	retval = -EAGAIN;
1628 	if (as) {
1629 		retval = processcompl(as, (void __user * __user *)arg);
1630 		free_async(as);
1631 	}
1632 	return retval;
1633 }
1634 
1635 #ifdef CONFIG_COMPAT
1636 static int proc_control_compat(struct dev_state *ps,
1637 				struct usbdevfs_ctrltransfer32 __user *p32)
1638 {
1639         struct usbdevfs_ctrltransfer __user *p;
1640         __u32 udata;
1641         p = compat_alloc_user_space(sizeof(*p));
1642         if (copy_in_user(p, p32, (sizeof(*p32) - sizeof(compat_caddr_t))) ||
1643             get_user(udata, &p32->data) ||
1644 	    put_user(compat_ptr(udata), &p->data))
1645 		return -EFAULT;
1646         return proc_control(ps, p);
1647 }
1648 
1649 static int proc_bulk_compat(struct dev_state *ps,
1650 			struct usbdevfs_bulktransfer32 __user *p32)
1651 {
1652         struct usbdevfs_bulktransfer __user *p;
1653         compat_uint_t n;
1654         compat_caddr_t addr;
1655 
1656         p = compat_alloc_user_space(sizeof(*p));
1657 
1658         if (get_user(n, &p32->ep) || put_user(n, &p->ep) ||
1659             get_user(n, &p32->len) || put_user(n, &p->len) ||
1660             get_user(n, &p32->timeout) || put_user(n, &p->timeout) ||
1661             get_user(addr, &p32->data) || put_user(compat_ptr(addr), &p->data))
1662                 return -EFAULT;
1663 
1664         return proc_bulk(ps, p);
1665 }
1666 static int proc_disconnectsignal_compat(struct dev_state *ps, void __user *arg)
1667 {
1668 	struct usbdevfs_disconnectsignal32 ds;
1669 
1670 	if (copy_from_user(&ds, arg, sizeof(ds)))
1671 		return -EFAULT;
1672 	ps->discsignr = ds.signr;
1673 	ps->disccontext = compat_ptr(ds.context);
1674 	return 0;
1675 }
1676 
1677 static int get_urb32(struct usbdevfs_urb *kurb,
1678 		     struct usbdevfs_urb32 __user *uurb)
1679 {
1680 	__u32  uptr;
1681 	if (!access_ok(VERIFY_READ, uurb, sizeof(*uurb)) ||
1682 	    __get_user(kurb->type, &uurb->type) ||
1683 	    __get_user(kurb->endpoint, &uurb->endpoint) ||
1684 	    __get_user(kurb->status, &uurb->status) ||
1685 	    __get_user(kurb->flags, &uurb->flags) ||
1686 	    __get_user(kurb->buffer_length, &uurb->buffer_length) ||
1687 	    __get_user(kurb->actual_length, &uurb->actual_length) ||
1688 	    __get_user(kurb->start_frame, &uurb->start_frame) ||
1689 	    __get_user(kurb->number_of_packets, &uurb->number_of_packets) ||
1690 	    __get_user(kurb->error_count, &uurb->error_count) ||
1691 	    __get_user(kurb->signr, &uurb->signr))
1692 		return -EFAULT;
1693 
1694 	if (__get_user(uptr, &uurb->buffer))
1695 		return -EFAULT;
1696 	kurb->buffer = compat_ptr(uptr);
1697 	if (__get_user(uptr, &uurb->usercontext))
1698 		return -EFAULT;
1699 	kurb->usercontext = compat_ptr(uptr);
1700 
1701 	return 0;
1702 }
1703 
1704 static int proc_submiturb_compat(struct dev_state *ps, void __user *arg)
1705 {
1706 	struct usbdevfs_urb uurb;
1707 
1708 	if (get_urb32(&uurb, (struct usbdevfs_urb32 __user *)arg))
1709 		return -EFAULT;
1710 
1711 	return proc_do_submiturb(ps, &uurb,
1712 			((struct usbdevfs_urb32 __user *)arg)->iso_frame_desc,
1713 			arg);
1714 }
1715 
1716 static int processcompl_compat(struct async *as, void __user * __user *arg)
1717 {
1718 	struct urb *urb = as->urb;
1719 	struct usbdevfs_urb32 __user *userurb = as->userurb;
1720 	void __user *addr = as->userurb;
1721 	unsigned int i;
1722 
1723 	if (as->userbuffer && urb->actual_length) {
1724 		if (copy_urb_data_to_user(as->userbuffer, urb))
1725 			return -EFAULT;
1726 	}
1727 	if (put_user(as->status, &userurb->status))
1728 		return -EFAULT;
1729 	if (put_user(urb->actual_length, &userurb->actual_length))
1730 		return -EFAULT;
1731 	if (put_user(urb->error_count, &userurb->error_count))
1732 		return -EFAULT;
1733 
1734 	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1735 		for (i = 0; i < urb->number_of_packets; i++) {
1736 			if (put_user(urb->iso_frame_desc[i].actual_length,
1737 				     &userurb->iso_frame_desc[i].actual_length))
1738 				return -EFAULT;
1739 			if (put_user(urb->iso_frame_desc[i].status,
1740 				     &userurb->iso_frame_desc[i].status))
1741 				return -EFAULT;
1742 		}
1743 	}
1744 
1745 	if (put_user(ptr_to_compat(addr), (u32 __user *)arg))
1746 		return -EFAULT;
1747 	return 0;
1748 }
1749 
1750 static int proc_reapurb_compat(struct dev_state *ps, void __user *arg)
1751 {
1752 	struct async *as = reap_as(ps);
1753 	if (as) {
1754 		int retval = processcompl_compat(as, (void __user * __user *)arg);
1755 		free_async(as);
1756 		return retval;
1757 	}
1758 	if (signal_pending(current))
1759 		return -EINTR;
1760 	return -EIO;
1761 }
1762 
1763 static int proc_reapurbnonblock_compat(struct dev_state *ps, void __user *arg)
1764 {
1765 	int retval;
1766 	struct async *as;
1767 
1768 	retval = -EAGAIN;
1769 	as = async_getcompleted(ps);
1770 	if (as) {
1771 		retval = processcompl_compat(as, (void __user * __user *)arg);
1772 		free_async(as);
1773 	}
1774 	return retval;
1775 }
1776 
1777 
1778 #endif
1779 
1780 static int proc_disconnectsignal(struct dev_state *ps, void __user *arg)
1781 {
1782 	struct usbdevfs_disconnectsignal ds;
1783 
1784 	if (copy_from_user(&ds, arg, sizeof(ds)))
1785 		return -EFAULT;
1786 	ps->discsignr = ds.signr;
1787 	ps->disccontext = ds.context;
1788 	return 0;
1789 }
1790 
1791 static int proc_claiminterface(struct dev_state *ps, void __user *arg)
1792 {
1793 	unsigned int ifnum;
1794 
1795 	if (get_user(ifnum, (unsigned int __user *)arg))
1796 		return -EFAULT;
1797 	return claimintf(ps, ifnum);
1798 }
1799 
1800 static int proc_releaseinterface(struct dev_state *ps, void __user *arg)
1801 {
1802 	unsigned int ifnum;
1803 	int ret;
1804 
1805 	if (get_user(ifnum, (unsigned int __user *)arg))
1806 		return -EFAULT;
1807 	if ((ret = releaseintf(ps, ifnum)) < 0)
1808 		return ret;
1809 	destroy_async_on_interface (ps, ifnum);
1810 	return 0;
1811 }
1812 
1813 static int proc_ioctl(struct dev_state *ps, struct usbdevfs_ioctl *ctl)
1814 {
1815 	int			size;
1816 	void			*buf = NULL;
1817 	int			retval = 0;
1818 	struct usb_interface    *intf = NULL;
1819 	struct usb_driver       *driver = NULL;
1820 
1821 	/* alloc buffer */
1822 	if ((size = _IOC_SIZE(ctl->ioctl_code)) > 0) {
1823 		buf = kmalloc(size, GFP_KERNEL);
1824 		if (buf == NULL)
1825 			return -ENOMEM;
1826 		if ((_IOC_DIR(ctl->ioctl_code) & _IOC_WRITE)) {
1827 			if (copy_from_user(buf, ctl->data, size)) {
1828 				kfree(buf);
1829 				return -EFAULT;
1830 			}
1831 		} else {
1832 			memset(buf, 0, size);
1833 		}
1834 	}
1835 
1836 	if (!connected(ps)) {
1837 		kfree(buf);
1838 		return -ENODEV;
1839 	}
1840 
1841 	if (ps->dev->state != USB_STATE_CONFIGURED)
1842 		retval = -EHOSTUNREACH;
1843 	else if (!(intf = usb_ifnum_to_if(ps->dev, ctl->ifno)))
1844 		retval = -EINVAL;
1845 	else switch (ctl->ioctl_code) {
1846 
1847 	/* disconnect kernel driver from interface */
1848 	case USBDEVFS_DISCONNECT:
1849 		if (intf->dev.driver) {
1850 			driver = to_usb_driver(intf->dev.driver);
1851 			dev_dbg(&intf->dev, "disconnect by usbfs\n");
1852 			usb_driver_release_interface(driver, intf);
1853 		} else
1854 			retval = -ENODATA;
1855 		break;
1856 
1857 	/* let kernel drivers try to (re)bind to the interface */
1858 	case USBDEVFS_CONNECT:
1859 		if (!intf->dev.driver)
1860 			retval = device_attach(&intf->dev);
1861 		else
1862 			retval = -EBUSY;
1863 		break;
1864 
1865 	/* talk directly to the interface's driver */
1866 	default:
1867 		if (intf->dev.driver)
1868 			driver = to_usb_driver(intf->dev.driver);
1869 		if (driver == NULL || driver->unlocked_ioctl == NULL) {
1870 			retval = -ENOTTY;
1871 		} else {
1872 			retval = driver->unlocked_ioctl(intf, ctl->ioctl_code, buf);
1873 			if (retval == -ENOIOCTLCMD)
1874 				retval = -ENOTTY;
1875 		}
1876 	}
1877 
1878 	/* cleanup and return */
1879 	if (retval >= 0
1880 			&& (_IOC_DIR(ctl->ioctl_code) & _IOC_READ) != 0
1881 			&& size > 0
1882 			&& copy_to_user(ctl->data, buf, size) != 0)
1883 		retval = -EFAULT;
1884 
1885 	kfree(buf);
1886 	return retval;
1887 }
1888 
1889 static int proc_ioctl_default(struct dev_state *ps, void __user *arg)
1890 {
1891 	struct usbdevfs_ioctl	ctrl;
1892 
1893 	if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
1894 		return -EFAULT;
1895 	return proc_ioctl(ps, &ctrl);
1896 }
1897 
1898 #ifdef CONFIG_COMPAT
1899 static int proc_ioctl_compat(struct dev_state *ps, compat_uptr_t arg)
1900 {
1901 	struct usbdevfs_ioctl32 __user *uioc;
1902 	struct usbdevfs_ioctl ctrl;
1903 	u32 udata;
1904 
1905 	uioc = compat_ptr((long)arg);
1906 	if (!access_ok(VERIFY_READ, uioc, sizeof(*uioc)) ||
1907 	    __get_user(ctrl.ifno, &uioc->ifno) ||
1908 	    __get_user(ctrl.ioctl_code, &uioc->ioctl_code) ||
1909 	    __get_user(udata, &uioc->data))
1910 		return -EFAULT;
1911 	ctrl.data = compat_ptr(udata);
1912 
1913 	return proc_ioctl(ps, &ctrl);
1914 }
1915 #endif
1916 
1917 static int proc_claim_port(struct dev_state *ps, void __user *arg)
1918 {
1919 	unsigned portnum;
1920 	int rc;
1921 
1922 	if (get_user(portnum, (unsigned __user *) arg))
1923 		return -EFAULT;
1924 	rc = usb_hub_claim_port(ps->dev, portnum, ps);
1925 	if (rc == 0)
1926 		snoop(&ps->dev->dev, "port %d claimed by process %d: %s\n",
1927 			portnum, task_pid_nr(current), current->comm);
1928 	return rc;
1929 }
1930 
1931 static int proc_release_port(struct dev_state *ps, void __user *arg)
1932 {
1933 	unsigned portnum;
1934 
1935 	if (get_user(portnum, (unsigned __user *) arg))
1936 		return -EFAULT;
1937 	return usb_hub_release_port(ps->dev, portnum, ps);
1938 }
1939 
1940 static int proc_get_capabilities(struct dev_state *ps, void __user *arg)
1941 {
1942 	__u32 caps;
1943 
1944 	caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM;
1945 	if (!ps->dev->bus->no_stop_on_short)
1946 		caps |= USBDEVFS_CAP_BULK_CONTINUATION;
1947 	if (ps->dev->bus->sg_tablesize)
1948 		caps |= USBDEVFS_CAP_BULK_SCATTER_GATHER;
1949 
1950 	if (put_user(caps, (__u32 __user *)arg))
1951 		return -EFAULT;
1952 
1953 	return 0;
1954 }
1955 
1956 static int proc_disconnect_claim(struct dev_state *ps, void __user *arg)
1957 {
1958 	struct usbdevfs_disconnect_claim dc;
1959 	struct usb_interface *intf;
1960 
1961 	if (copy_from_user(&dc, arg, sizeof(dc)))
1962 		return -EFAULT;
1963 
1964 	intf = usb_ifnum_to_if(ps->dev, dc.interface);
1965 	if (!intf)
1966 		return -EINVAL;
1967 
1968 	if (intf->dev.driver) {
1969 		struct usb_driver *driver = to_usb_driver(intf->dev.driver);
1970 
1971 		if ((dc.flags & USBDEVFS_DISCONNECT_CLAIM_IF_DRIVER) &&
1972 				strncmp(dc.driver, intf->dev.driver->name,
1973 					sizeof(dc.driver)) != 0)
1974 			return -EBUSY;
1975 
1976 		if ((dc.flags & USBDEVFS_DISCONNECT_CLAIM_EXCEPT_DRIVER) &&
1977 				strncmp(dc.driver, intf->dev.driver->name,
1978 					sizeof(dc.driver)) == 0)
1979 			return -EBUSY;
1980 
1981 		dev_dbg(&intf->dev, "disconnect by usbfs\n");
1982 		usb_driver_release_interface(driver, intf);
1983 	}
1984 
1985 	return claimintf(ps, dc.interface);
1986 }
1987 
1988 /*
1989  * NOTE:  All requests here that have interface numbers as parameters
1990  * are assuming that somehow the configuration has been prevented from
1991  * changing.  But there's no mechanism to ensure that...
1992  */
1993 static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
1994 				void __user *p)
1995 {
1996 	struct dev_state *ps = file->private_data;
1997 	struct inode *inode = file_inode(file);
1998 	struct usb_device *dev = ps->dev;
1999 	int ret = -ENOTTY;
2000 
2001 	if (!(file->f_mode & FMODE_WRITE))
2002 		return -EPERM;
2003 
2004 	usb_lock_device(dev);
2005 	if (!connected(ps)) {
2006 		usb_unlock_device(dev);
2007 		return -ENODEV;
2008 	}
2009 
2010 	switch (cmd) {
2011 	case USBDEVFS_CONTROL:
2012 		snoop(&dev->dev, "%s: CONTROL\n", __func__);
2013 		ret = proc_control(ps, p);
2014 		if (ret >= 0)
2015 			inode->i_mtime = CURRENT_TIME;
2016 		break;
2017 
2018 	case USBDEVFS_BULK:
2019 		snoop(&dev->dev, "%s: BULK\n", __func__);
2020 		ret = proc_bulk(ps, p);
2021 		if (ret >= 0)
2022 			inode->i_mtime = CURRENT_TIME;
2023 		break;
2024 
2025 	case USBDEVFS_RESETEP:
2026 		snoop(&dev->dev, "%s: RESETEP\n", __func__);
2027 		ret = proc_resetep(ps, p);
2028 		if (ret >= 0)
2029 			inode->i_mtime = CURRENT_TIME;
2030 		break;
2031 
2032 	case USBDEVFS_RESET:
2033 		snoop(&dev->dev, "%s: RESET\n", __func__);
2034 		ret = proc_resetdevice(ps);
2035 		break;
2036 
2037 	case USBDEVFS_CLEAR_HALT:
2038 		snoop(&dev->dev, "%s: CLEAR_HALT\n", __func__);
2039 		ret = proc_clearhalt(ps, p);
2040 		if (ret >= 0)
2041 			inode->i_mtime = CURRENT_TIME;
2042 		break;
2043 
2044 	case USBDEVFS_GETDRIVER:
2045 		snoop(&dev->dev, "%s: GETDRIVER\n", __func__);
2046 		ret = proc_getdriver(ps, p);
2047 		break;
2048 
2049 	case USBDEVFS_CONNECTINFO:
2050 		snoop(&dev->dev, "%s: CONNECTINFO\n", __func__);
2051 		ret = proc_connectinfo(ps, p);
2052 		break;
2053 
2054 	case USBDEVFS_SETINTERFACE:
2055 		snoop(&dev->dev, "%s: SETINTERFACE\n", __func__);
2056 		ret = proc_setintf(ps, p);
2057 		break;
2058 
2059 	case USBDEVFS_SETCONFIGURATION:
2060 		snoop(&dev->dev, "%s: SETCONFIGURATION\n", __func__);
2061 		ret = proc_setconfig(ps, p);
2062 		break;
2063 
2064 	case USBDEVFS_SUBMITURB:
2065 		snoop(&dev->dev, "%s: SUBMITURB\n", __func__);
2066 		ret = proc_submiturb(ps, p);
2067 		if (ret >= 0)
2068 			inode->i_mtime = CURRENT_TIME;
2069 		break;
2070 
2071 #ifdef CONFIG_COMPAT
2072 	case USBDEVFS_CONTROL32:
2073 		snoop(&dev->dev, "%s: CONTROL32\n", __func__);
2074 		ret = proc_control_compat(ps, p);
2075 		if (ret >= 0)
2076 			inode->i_mtime = CURRENT_TIME;
2077 		break;
2078 
2079 	case USBDEVFS_BULK32:
2080 		snoop(&dev->dev, "%s: BULK32\n", __func__);
2081 		ret = proc_bulk_compat(ps, p);
2082 		if (ret >= 0)
2083 			inode->i_mtime = CURRENT_TIME;
2084 		break;
2085 
2086 	case USBDEVFS_DISCSIGNAL32:
2087 		snoop(&dev->dev, "%s: DISCSIGNAL32\n", __func__);
2088 		ret = proc_disconnectsignal_compat(ps, p);
2089 		break;
2090 
2091 	case USBDEVFS_SUBMITURB32:
2092 		snoop(&dev->dev, "%s: SUBMITURB32\n", __func__);
2093 		ret = proc_submiturb_compat(ps, p);
2094 		if (ret >= 0)
2095 			inode->i_mtime = CURRENT_TIME;
2096 		break;
2097 
2098 	case USBDEVFS_REAPURB32:
2099 		snoop(&dev->dev, "%s: REAPURB32\n", __func__);
2100 		ret = proc_reapurb_compat(ps, p);
2101 		break;
2102 
2103 	case USBDEVFS_REAPURBNDELAY32:
2104 		snoop(&dev->dev, "%s: REAPURBNDELAY32\n", __func__);
2105 		ret = proc_reapurbnonblock_compat(ps, p);
2106 		break;
2107 
2108 	case USBDEVFS_IOCTL32:
2109 		snoop(&dev->dev, "%s: IOCTL32\n", __func__);
2110 		ret = proc_ioctl_compat(ps, ptr_to_compat(p));
2111 		break;
2112 #endif
2113 
2114 	case USBDEVFS_DISCARDURB:
2115 		snoop(&dev->dev, "%s: DISCARDURB\n", __func__);
2116 		ret = proc_unlinkurb(ps, p);
2117 		break;
2118 
2119 	case USBDEVFS_REAPURB:
2120 		snoop(&dev->dev, "%s: REAPURB\n", __func__);
2121 		ret = proc_reapurb(ps, p);
2122 		break;
2123 
2124 	case USBDEVFS_REAPURBNDELAY:
2125 		snoop(&dev->dev, "%s: REAPURBNDELAY\n", __func__);
2126 		ret = proc_reapurbnonblock(ps, p);
2127 		break;
2128 
2129 	case USBDEVFS_DISCSIGNAL:
2130 		snoop(&dev->dev, "%s: DISCSIGNAL\n", __func__);
2131 		ret = proc_disconnectsignal(ps, p);
2132 		break;
2133 
2134 	case USBDEVFS_CLAIMINTERFACE:
2135 		snoop(&dev->dev, "%s: CLAIMINTERFACE\n", __func__);
2136 		ret = proc_claiminterface(ps, p);
2137 		break;
2138 
2139 	case USBDEVFS_RELEASEINTERFACE:
2140 		snoop(&dev->dev, "%s: RELEASEINTERFACE\n", __func__);
2141 		ret = proc_releaseinterface(ps, p);
2142 		break;
2143 
2144 	case USBDEVFS_IOCTL:
2145 		snoop(&dev->dev, "%s: IOCTL\n", __func__);
2146 		ret = proc_ioctl_default(ps, p);
2147 		break;
2148 
2149 	case USBDEVFS_CLAIM_PORT:
2150 		snoop(&dev->dev, "%s: CLAIM_PORT\n", __func__);
2151 		ret = proc_claim_port(ps, p);
2152 		break;
2153 
2154 	case USBDEVFS_RELEASE_PORT:
2155 		snoop(&dev->dev, "%s: RELEASE_PORT\n", __func__);
2156 		ret = proc_release_port(ps, p);
2157 		break;
2158 	case USBDEVFS_GET_CAPABILITIES:
2159 		ret = proc_get_capabilities(ps, p);
2160 		break;
2161 	case USBDEVFS_DISCONNECT_CLAIM:
2162 		ret = proc_disconnect_claim(ps, p);
2163 		break;
2164 	}
2165 	usb_unlock_device(dev);
2166 	if (ret >= 0)
2167 		inode->i_atime = CURRENT_TIME;
2168 	return ret;
2169 }
2170 
2171 static long usbdev_ioctl(struct file *file, unsigned int cmd,
2172 			unsigned long arg)
2173 {
2174 	int ret;
2175 
2176 	ret = usbdev_do_ioctl(file, cmd, (void __user *)arg);
2177 
2178 	return ret;
2179 }
2180 
2181 #ifdef CONFIG_COMPAT
2182 static long usbdev_compat_ioctl(struct file *file, unsigned int cmd,
2183 			unsigned long arg)
2184 {
2185 	int ret;
2186 
2187 	ret = usbdev_do_ioctl(file, cmd, compat_ptr(arg));
2188 
2189 	return ret;
2190 }
2191 #endif
2192 
2193 /* No kernel lock - fine */
2194 static unsigned int usbdev_poll(struct file *file,
2195 				struct poll_table_struct *wait)
2196 {
2197 	struct dev_state *ps = file->private_data;
2198 	unsigned int mask = 0;
2199 
2200 	poll_wait(file, &ps->wait, wait);
2201 	if (file->f_mode & FMODE_WRITE && !list_empty(&ps->async_completed))
2202 		mask |= POLLOUT | POLLWRNORM;
2203 	if (!connected(ps))
2204 		mask |= POLLERR | POLLHUP;
2205 	return mask;
2206 }
2207 
2208 const struct file_operations usbdev_file_operations = {
2209 	.owner =	  THIS_MODULE,
2210 	.llseek =	  usbdev_lseek,
2211 	.read =		  usbdev_read,
2212 	.poll =		  usbdev_poll,
2213 	.unlocked_ioctl = usbdev_ioctl,
2214 #ifdef CONFIG_COMPAT
2215 	.compat_ioctl =   usbdev_compat_ioctl,
2216 #endif
2217 	.open =		  usbdev_open,
2218 	.release =	  usbdev_release,
2219 };
2220 
2221 static void usbdev_remove(struct usb_device *udev)
2222 {
2223 	struct dev_state *ps;
2224 	struct siginfo sinfo;
2225 
2226 	while (!list_empty(&udev->filelist)) {
2227 		ps = list_entry(udev->filelist.next, struct dev_state, list);
2228 		destroy_all_async(ps);
2229 		wake_up_all(&ps->wait);
2230 		list_del_init(&ps->list);
2231 		if (ps->discsignr) {
2232 			sinfo.si_signo = ps->discsignr;
2233 			sinfo.si_errno = EPIPE;
2234 			sinfo.si_code = SI_ASYNCIO;
2235 			sinfo.si_addr = ps->disccontext;
2236 			kill_pid_info_as_cred(ps->discsignr, &sinfo,
2237 					ps->disc_pid, ps->cred, ps->secid);
2238 		}
2239 	}
2240 }
2241 
2242 static int usbdev_notify(struct notifier_block *self,
2243 			       unsigned long action, void *dev)
2244 {
2245 	switch (action) {
2246 	case USB_DEVICE_ADD:
2247 		break;
2248 	case USB_DEVICE_REMOVE:
2249 		usbdev_remove(dev);
2250 		break;
2251 	}
2252 	return NOTIFY_OK;
2253 }
2254 
2255 static struct notifier_block usbdev_nb = {
2256 	.notifier_call = 	usbdev_notify,
2257 };
2258 
2259 static struct cdev usb_device_cdev;
2260 
2261 int __init usb_devio_init(void)
2262 {
2263 	int retval;
2264 
2265 	retval = register_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX,
2266 					"usb_device");
2267 	if (retval) {
2268 		printk(KERN_ERR "Unable to register minors for usb_device\n");
2269 		goto out;
2270 	}
2271 	cdev_init(&usb_device_cdev, &usbdev_file_operations);
2272 	retval = cdev_add(&usb_device_cdev, USB_DEVICE_DEV, USB_DEVICE_MAX);
2273 	if (retval) {
2274 		printk(KERN_ERR "Unable to get usb_device major %d\n",
2275 		       USB_DEVICE_MAJOR);
2276 		goto error_cdev;
2277 	}
2278 	usb_register_notify(&usbdev_nb);
2279 out:
2280 	return retval;
2281 
2282 error_cdev:
2283 	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
2284 	goto out;
2285 }
2286 
2287 void usb_devio_cleanup(void)
2288 {
2289 	usb_unregister_notify(&usbdev_nb);
2290 	cdev_del(&usb_device_cdev);
2291 	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
2292 }
2293