text: /*****************************************************************************/
  
  /*
   *      devio.c  --  User space communication with USB devices.
   *
   *      Copyright (C) 1999-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
   *
   *      This program is free software; you can redistribute it and/or modify
   *      it under the terms of the GNU General Public License as published by
   *      the Free Software Foundation; either version 2 of the License, or
   *      (at your option) any later version.
   *
   *      This program is distributed in the hope that it will be useful,
   *      but WITHOUT ANY WARRANTY; without even the implied warranty of
   *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *      GNU General Public License for more details.
   *
   *      You should have received a copy of the GNU General Public License
   *      along with this program; if not, write to the Free Software
   *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   *
   *  This file implements the usbfs/x/y files, where
   *  x is the bus number and y the device number.
   *
   *  It allows user space programs/"drivers" to communicate directly
   *  with USB devices without intervening kernel driver.
   *
   *  Revision history
   *    22.12.1999   0.1   Initial release (split from proc_usb.c)
   *    04.01.2000   0.2   Turned into its own filesystem
   *    30.09.2005   0.3   Fix user-triggerable oops in async URB delivery
   *    			 (CAN-2005-3055)
   */
  
  /*****************************************************************************/
  
  #include <linux/fs.h>
  #include <linux/mm.h>
  #include <linux/slab.h>
  #include <linux/signal.h>
  #include <linux/poll.h>
  #include <linux/module.h>
  #include <linux/usb.h>
  #include <linux/usbdevice_fs.h>
  #include <linux/usb/hcd.h>	/* for usbcore internals */
  #include <linux/cdev.h>
  #include <linux/notifier.h>
  #include <linux/security.h>
  #include <linux/user_namespace.h>
  #include <linux/scatterlist.h>
  #include <asm/uaccess.h>
  #include <asm/byteorder.h>
  #include <linux/moduleparam.h>
  
  #include "usb.h"
  
  #define USB_MAXBUS			64
  #define USB_DEVICE_MAX			USB_MAXBUS * 128
  #define USB_SG_SIZE			16384 /* split-size for large txs */
  
  /* Mutual exclusion for removal, open, and release */
  DEFINE_MUTEX(usbfs_mutex);
  
  struct dev_state {
  	struct list_head list;      /* state list */
  	struct usb_device *dev;
  	struct file *file;
  	spinlock_t lock;            /* protects the async urb lists */
  	struct list_head async_pending;
  	struct list_head async_completed;
  	wait_queue_head_t wait;     /* wake up if a request completed */
  	unsigned int discsignr;
  	struct pid *disc_pid;
  	const struct cred *cred;
  	void __user *disccontext;
  	unsigned long ifclaimed;
  	u32 secid;
  	u32 disabled_bulk_eps;
  };
  
  struct async {
  	struct list_head asynclist;
  	struct dev_state *ps;
  	struct pid *pid;
  	const struct cred *cred;
  	unsigned int signr;
  	unsigned int ifnum;
  	void __user *userbuffer;
  	void __user *userurb;
  	struct urb *urb;
  	unsigned int mem_usage;
  	int status;
  	u32 secid;
  	u8 bulk_addr;
  	u8 bulk_status;
  };
  
  static bool usbfs_snoop;
  module_param(usbfs_snoop, bool, S_IRUGO | S_IWUSR);
  MODULE_PARM_DESC(usbfs_snoop, "true to log all usbfs traffic");
  
  #define snoop(dev, format, arg...)				\
  	do {							\
  		if (usbfs_snoop)				\
  			dev_info(dev , format , ## arg);	\
  	} while (0)
  
  enum snoop_when {
  	SUBMIT, COMPLETE
  };
  
  #define USB_DEVICE_DEV		MKDEV(USB_DEVICE_MAJOR, 0)
  
  /* Limit on the total amount of memory we can allocate for transfers */
  static unsigned usbfs_memory_mb = 16;
  module_param(usbfs_memory_mb, uint, 0644);
  MODULE_PARM_DESC(usbfs_memory_mb,
  		"maximum MB allowed for usbfs buffers (0 = no limit)");
  
  /* Hard limit, necessary to avoid aithmetic overflow */
  #define USBFS_XFER_MAX		(UINT_MAX / 2 - 1000000)
  
  static atomic_t usbfs_memory_usage;	/* Total memory currently allocated */
  
  /* Check whether it's okay to allocate more memory for a transfer */
  static int usbfs_increase_memory_usage(unsigned amount)
  {
  	unsigned lim;
  
  	/*
  	 * Convert usbfs_memory_mb to bytes, avoiding overflows.
  	 * 0 means use the hard limit (effectively unlimited).
  	 */
  	lim = ACCESS_ONCE(usbfs_memory_mb);
  	if (lim == 0 || lim > (USBFS_XFER_MAX >> 20))
  		lim = USBFS_XFER_MAX;
  	else
  		lim <<= 20;
  
  	atomic_add(amount, &usbfs_memory_usage);
  	if (atomic_read(&usbfs_memory_usage) <= lim)
  		return 0;
  	atomic_sub(amount, &usbfs_memory_usage);
  	return -ENOMEM;
  }
  
  /* Memory for a transfer is being deallocated */
  static void usbfs_decrease_memory_usage(unsigned amount)
  {
  	atomic_sub(amount, &usbfs_memory_usage);
  }
  
  static int connected(struct dev_state *ps)
  {
  	return (!list_empty(&ps->list) &&
  			ps->dev->state != USB_STATE_NOTATTACHED);
  }
  
  static loff_t usbdev_lseek(struct file *file, loff_t offset, int orig)
  {
  	loff_t ret;
  
  	mutex_lock(&file->f_dentry->d_inode->i_mutex);
  
  	switch (orig) {
  	case 0:
  		file->f_pos = offset;
  		ret = file->f_pos;
  		break;
  	case 1:
  		file->f_pos += offset;
  		ret = file->f_pos;
  		break;
  	case 2:
  	default:
  		ret = -EINVAL;
  	}
  
  	mutex_unlock(&file->f_dentry->d_inode->i_mutex);
  	return ret;
  }
  
  static ssize_t usbdev_read(struct file *file, char __user *buf, size_t nbytes,
  			   loff_t *ppos)
  {
  	struct dev_state *ps = file->private_data;
  	struct usb_device *dev = ps->dev;
  	ssize_t ret = 0;
  	unsigned len;
  	loff_t pos;
  	int i;
  
  	pos = *ppos;
  	usb_lock_device(dev);
  	if (!connected(ps)) {
  		ret = -ENODEV;
  		goto err;
  	} else if (pos < 0) {
  		ret = -EINVAL;
  		goto err;
  	}
  
  	if (pos < sizeof(struct usb_device_descriptor)) {
  		/* 18 bytes - fits on the stack */
  		struct usb_device_descriptor temp_desc;
  
  		memcpy(&temp_desc, &dev->descriptor, sizeof(dev->descriptor));
  		le16_to_cpus(&temp_desc.bcdUSB);
  		le16_to_cpus(&temp_desc.idVendor);
  		le16_to_cpus(&temp_desc.idProduct);
  		le16_to_cpus(&temp_desc.bcdDevice);
  
  		len = sizeof(struct usb_device_descriptor) - pos;
  		if (len > nbytes)
  			len = nbytes;
  		if (copy_to_user(buf, ((char *)&temp_desc) + pos, len)) {
  			ret = -EFAULT;
  			goto err;
  		}
  
  		*ppos += len;
  		buf += len;
  		nbytes -= len;
  		ret += len;
  	}
  
  	pos = sizeof(struct usb_device_descriptor);
  	for (i = 0; nbytes && i < dev->descriptor.bNumConfigurations; i++) {
  		struct usb_config_descriptor *config =
  			(struct usb_config_descriptor *)dev->rawdescriptors[i];
  		unsigned int length = le16_to_cpu(config->wTotalLength);
  
  		if (*ppos < pos + length) {
  
  			/* The descriptor may claim to be longer than it
  			 * really is.  Here is the actual allocated length. */
  			unsigned alloclen =
  				le16_to_cpu(dev->config[i].desc.wTotalLength);
  
  			len = length - (*ppos - pos);
  			if (len > nbytes)
  				len = nbytes;
  
  			/* Simply don't write (skip over) unallocated parts */
  			if (alloclen > (*ppos - pos)) {
  				alloclen -= (*ppos - pos);
  				if (copy_to_user(buf,
  				    dev->rawdescriptors[i] + (*ppos - pos),
  				    min(len, alloclen))) {
  					ret = -EFAULT;
  					goto err;
  				}
  			}
  
  			*ppos += len;
  			buf += len;
  			nbytes -= len;
  			ret += len;
  		}
  
  		pos += length;
  	}
  
  err:
  	usb_unlock_device(dev);
  	return ret;
  }
  
  /*
   * async list handling
   */
  
  static struct async *alloc_async(unsigned int numisoframes)
  {
  	struct async *as;
  
  	as = kzalloc(sizeof(struct async), GFP_KERNEL);
  	if (!as)
  		return NULL;
  	as->urb = usb_alloc_urb(numisoframes, GFP_KERNEL);
  	if (!as->urb) {
  		kfree(as);
  		return NULL;
  	}
  	return as;
  }
  
  static void free_async(struct async *as)
  {
  	int i;
  
  	put_pid(as->pid);
  	if (as->cred)
  		put_cred(as->cred);
  	for (i = 0; i < as->urb->num_sgs; i++) {
  		if (sg_page(&as->urb->sg[i]))
  			kfree(sg_virt(&as->urb->sg[i]));
  	}
  	kfree(as->urb->sg);
  	kfree(as->urb->transfer_buffer);
  	kfree(as->urb->setup_packet);
  	usb_free_urb(as->urb);
  	usbfs_decrease_memory_usage(as->mem_usage);
  	kfree(as);
  }
  
  static void async_newpending(struct async *as)
  {
  	struct dev_state *ps = as->ps;
  	unsigned long flags;
  
  	spin_lock_irqsave(&ps->lock, flags);
  	list_add_tail(&as->asynclist, &ps->async_pending);
  	spin_unlock_irqrestore(&ps->lock, flags);
  }
  
  static void async_removepending(struct async *as)
  {
  	struct dev_state *ps = as->ps;
  	unsigned long flags;
  
  	spin_lock_irqsave(&ps->lock, flags);
  	list_del_init(&as->asynclist);
  	spin_unlock_irqrestore(&ps->lock, flags);
  }
  
  static struct async *async_getcompleted(struct dev_state *ps)
  {
  	unsigned long flags;
  	struct async *as = NULL;
  
  	spin_lock_irqsave(&ps->lock, flags);
  	if (!list_empty(&ps->async_completed)) {
  		as = list_entry(ps->async_completed.next, struct async,
  				asynclist);
  		list_del_init(&as->asynclist);
  	}
  	spin_unlock_irqrestore(&ps->lock, flags);
  	return as;
  }
  
  static struct async *async_getpending(struct dev_state *ps,
  					     void __user *userurb)
  {
  	struct async *as;
  
  	list_for_each_entry(as, &ps->async_pending, asynclist)
  		if (as->userurb == userurb) {
  			list_del_init(&as->asynclist);
  			return as;
  		}
  
  	return NULL;
  }
  
  static void snoop_urb(struct usb_device *udev,
  		void __user *userurb, int pipe, unsigned length,
  		int timeout_or_status, enum snoop_when when,
  		unsigned char *data, unsigned data_len)
  {
  	static const char *types[] = {"isoc", "int", "ctrl", "bulk"};
  	static const char *dirs[] = {"out", "in"};
  	int ep;
  	const char *t, *d;
  
  	if (!usbfs_snoop)
  		return;
  
  	ep = usb_pipeendpoint(pipe);
  	t = types[usb_pipetype(pipe)];
  	d = dirs[!!usb_pipein(pipe)];
  
  	if (userurb) {		/* Async */
  		if (when == SUBMIT)
  			dev_info(&udev->dev, "userurb %p, ep%d %s-%s, "
  					"length %u\n",
  					userurb, ep, t, d, length);
  		else
  			dev_info(&udev->dev, "userurb %p, ep%d %s-%s, "
  					"actual_length %u status %d\n",
  					userurb, ep, t, d, length,
  					timeout_or_status);
  	} else {
  		if (when == SUBMIT)
  			dev_info(&udev->dev, "ep%d %s-%s, length %u, "
  					"timeout %d\n",
  					ep, t, d, length, timeout_or_status);
  		else
  			dev_info(&udev->dev, "ep%d %s-%s, actual_length %u, "
  					"status %d\n",
  					ep, t, d, length, timeout_or_status);
  	}
  
  	if (data && data_len > 0) {
  		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
  			data, data_len, 1);
  	}
  }
  
  static void snoop_urb_data(struct urb *urb, unsigned len)
  {
  	int i, size;
  
  	if (!usbfs_snoop)
  		return;
  
  	if (urb->num_sgs == 0) {
  		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
  			urb->transfer_buffer, len, 1);
  		return;
  	}
  
  	for (i = 0; i < urb->num_sgs && len; i++) {
  		size = (len > USB_SG_SIZE) ? USB_SG_SIZE : len;
  		print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_NONE, 32, 1,
  			sg_virt(&urb->sg[i]), size, 1);
  		len -= size;
  	}
  }
  
  static int copy_urb_data_to_user(u8 __user *userbuffer, struct urb *urb)
  {
  	unsigned i, len, size;
  
  	if (urb->number_of_packets > 0)		/* Isochronous */
  		len = urb->transfer_buffer_length;
  	else					/* Non-Isoc */
  		len = urb->actual_length;
  
  	if (urb->num_sgs == 0) {
  		if (copy_to_user(userbuffer, urb->transfer_buffer, len))
  			return -EFAULT;
  		return 0;
  	}
  
  	for (i = 0; i < urb->num_sgs && len; i++) {
  		size = (len > USB_SG_SIZE) ? USB_SG_SIZE : len;
  		if (copy_to_user(userbuffer, sg_virt(&urb->sg[i]), size))
  			return -EFAULT;
  		userbuffer += size;
  		len -= size;
  	}
  
  	return 0;
  }
  
  #define AS_CONTINUATION	1
  #define AS_UNLINK	2
  
  static void cancel_bulk_urbs(struct dev_state *ps, unsigned bulk_addr)
  __releases(ps->lock)
  __acquires(ps->lock)
  {
  	struct urb *urb;
  	struct async *as;
  
  	/* Mark all the pending URBs that match bulk_addr, up to but not
  	 * including the first one without AS_CONTINUATION.  If such an
  	 * URB is encountered then a new transfer has already started so
  	 * the endpoint doesn't need to be disabled; otherwise it does.
  	 */
  	list_for_each_entry(as, &ps->async_pending, asynclist) {
  		if (as->bulk_addr == bulk_addr) {
  			if (as->bulk_status != AS_CONTINUATION)
  				goto rescan;
  			as->bulk_status = AS_UNLINK;
  			as->bulk_addr = 0;
  		}
  	}
  	ps->disabled_bulk_eps |= (1 << bulk_addr);
  
  	/* Now carefully unlink all the marked pending URBs */
   rescan:
  	list_for_each_entry(as, &ps->async_pending, asynclist) {
  		if (as->bulk_status == AS_UNLINK) {
  			as->bulk_status = 0;		/* Only once */
  			urb = as->urb;
  			usb_get_urb(urb);
  			spin_unlock(&ps->lock);		/* Allow completions */
  			usb_unlink_urb(urb);
  			usb_put_urb(urb);
  			spin_lock(&ps->lock);
  			goto rescan;
  		}
  	}
  }
  
  static void async_completed(struct urb *urb)
  {
  	struct async *as = urb->context;
  	struct dev_state *ps = as->ps;
  	struct siginfo sinfo;
  	struct pid *pid = NULL;
  	u32 secid = 0;
  	const struct cred *cred = NULL;
  	int signr;
  
  	spin_lock(&ps->lock);
  	list_move_tail(&as->asynclist, &ps->async_completed);
  	as->status = urb->status;
  	signr = as->signr;
  	if (signr) {
  		sinfo.si_signo = as->signr;
  		sinfo.si_errno = as->status;
  		sinfo.si_code = SI_ASYNCIO;
  		sinfo.si_addr = as->userurb;
  		pid = get_pid(as->pid);
  		cred = get_cred(as->cred);
  		secid = as->secid;
  	}
  	snoop(&urb->dev->dev, "urb complete\n");
  	snoop_urb(urb->dev, as->userurb, urb->pipe, urb->actual_length,
  			as->status, COMPLETE, NULL, 0);
  	if ((urb->transfer_flags & URB_DIR_MASK) == USB_DIR_IN)
  		snoop_urb_data(urb, urb->actual_length);
  
  	if (as->status < 0 && as->bulk_addr && as->status != -ECONNRESET &&
  			as->status != -ENOENT)
  		cancel_bulk_urbs(ps, as->bulk_addr);
  	spin_unlock(&ps->lock);
  
  	if (signr) {
  		kill_pid_info_as_cred(sinfo.si_signo, &sinfo, pid, cred, secid);
  		put_pid(pid);
  		put_cred(cred);
  	}
  
  	wake_up(&ps->wait);
  }
  
  static void destroy_async(struct dev_state *ps, struct list_head *list)
  {
  	struct urb *urb;
  	struct async *as;
  	unsigned long flags;
  
  	spin_lock_irqsave(&ps->lock, flags);
  	while (!list_empty(list)) {
  		as = list_entry(list->next, struct async, asynclist);
  		list_del_init(&as->asynclist);
  		urb = as->urb;
  		usb_get_urb(urb);
  
  		/* drop the spinlock so the completion handler can run */
  		spin_unlock_irqrestore(&ps->lock, flags);
  		usb_kill_urb(urb);
  		usb_put_urb(urb);
  		spin_lock_irqsave(&ps->lock, flags);
  	}
  	spin_unlock_irqrestore(&ps->lock, flags);
  }
  
  static void destroy_async_on_interface(struct dev_state *ps,
  				       unsigned int ifnum)
  {
  	struct list_head *p, *q, hitlist;
  	unsigned long flags;
  
  	INIT_LIST_HEAD(&hitlist);
  	spin_lock_irqsave(&ps->lock, flags);
  	list_for_each_safe(p, q, &ps->async_pending)
  		if (ifnum == list_entry(p, struct async, asynclist)->ifnum)
  			list_move_tail(p, &hitlist);
  	spin_unlock_irqrestore(&ps->lock, flags);
  	destroy_async(ps, &hitlist);
  }
  
  static void destroy_all_async(struct dev_state *ps)
  {
  	destroy_async(ps, &ps->async_pending);
  }
  
  /*
   * interface claims are made only at the request of user level code,
   * which can also release them (explicitly or by closing files).
   * they're also undone when devices disconnect.
   */
  
  static int driver_probe(struct usb_interface *intf,
  			const struct usb_device_id *id)
  {
  	return -ENODEV;
  }
  
  static void driver_disconnect(struct usb_interface *intf)
  {
  	struct dev_state *ps = usb_get_intfdata(intf);
  	unsigned int ifnum = intf->altsetting->desc.bInterfaceNumber;
  
  	if (!ps)
  		return;
  
  	/* NOTE:  this relies on usbcore having canceled and completed
  	 * all pending I/O requests; 2.6 does that.
  	 */
  
  	if (likely(ifnum < 8*sizeof(ps->ifclaimed)))
  		clear_bit(ifnum, &ps->ifclaimed);
  	else
  		dev_warn(&intf->dev, "interface number %u out of range\n",
  			 ifnum);
  
  	usb_set_intfdata(intf, NULL);
  
  	/* force async requests to complete */
  	destroy_async_on_interface(ps, ifnum);
  }
  
  /* The following routines are merely placeholders.  There is no way
   * to inform a user task about suspend or resumes.
   */
  static int driver_suspend(struct usb_interface *intf, pm_message_t msg)
  {
  	return 0;
  }
  
  static int driver_resume(struct usb_interface *intf)
  {
  	return 0;
  }
  
  struct usb_driver usbfs_driver = {
  	.name =		"usbfs",
  	.probe =	driver_probe,
  	.disconnect =	driver_disconnect,
  	.suspend =	driver_suspend,
  	.resume =	driver_resume,
  };
  
  static int claimintf(struct dev_state *ps, unsigned int ifnum)
  {
  	struct usb_device *dev = ps->dev;
  	struct usb_interface *intf;
  	int err;
  
  	if (ifnum >= 8*sizeof(ps->ifclaimed))
  		return -EINVAL;
  	/* already claimed */
  	if (test_bit(ifnum, &ps->ifclaimed))
  		return 0;
  
  	intf = usb_ifnum_to_if(dev, ifnum);
  	if (!intf)
  		err = -ENOENT;
  	else
  		err = usb_driver_claim_interface(&usbfs_driver, intf, ps);
  	if (err == 0)
  		set_bit(ifnum, &ps->ifclaimed);
  	return err;
  }
  
  static int releaseintf(struct dev_state *ps, unsigned int ifnum)
  {
  	struct usb_device *dev;
  	struct usb_interface *intf;
  	int err;
  
  	err = -EINVAL;
  	if (ifnum >= 8*sizeof(ps->ifclaimed))
  		return err;
  	dev = ps->dev;
  	intf = usb_ifnum_to_if(dev, ifnum);
  	if (!intf)
  		err = -ENOENT;
  	else if (test_and_clear_bit(ifnum, &ps->ifclaimed)) {
  		usb_driver_release_interface(&usbfs_driver, intf);
  		err = 0;
  	}
  	return err;
  }
  
  static int checkintf(struct dev_state *ps, unsigned int ifnum)
  {
  	if (ps->dev->state != USB_STATE_CONFIGURED)
  		return -EHOSTUNREACH;
  	if (ifnum >= 8*sizeof(ps->ifclaimed))
  		return -EINVAL;
  	if (test_bit(ifnum, &ps->ifclaimed))
  		return 0;
  	/* if not yet claimed, claim it for the driver */
  	dev_warn(&ps->dev->dev, "usbfs: process %d (%s) did not claim "
  		 "interface %u before use\n", task_pid_nr(current),
  		 current->comm, ifnum);
  	return claimintf(ps, ifnum);
  }
  
  static int findintfep(struct usb_device *dev, unsigned int ep)
  {
  	unsigned int i, j, e;
  	struct usb_interface *intf;
  	struct usb_host_interface *alts;
  	struct usb_endpoint_descriptor *endpt;
  
  	if (ep & ~(USB_DIR_IN|0xf))
  		return -EINVAL;
  	if (!dev->actconfig)
  		return -ESRCH;
  	for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
  		intf = dev->actconfig->interface[i];
  		for (j = 0; j < intf->num_altsetting; j++) {
  			alts = &intf->altsetting[j];
  			for (e = 0; e < alts->desc.bNumEndpoints; e++) {
  				endpt = &alts->endpoint[e].desc;
  				if (endpt->bEndpointAddress == ep)
  					return alts->desc.bInterfaceNumber;
  			}
  		}
  	}
  	return -ENOENT;
  }
  
  static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype,
  			   unsigned int request, unsigned int index)
  {
  	int ret = 0;
  	struct usb_host_interface *alt_setting;
  
  	if (ps->dev->state != USB_STATE_UNAUTHENTICATED
  	 && ps->dev->state != USB_STATE_ADDRESS
  	 && ps->dev->state != USB_STATE_CONFIGURED)
  		return -EHOSTUNREACH;
  	if (USB_TYPE_VENDOR == (USB_TYPE_MASK & requesttype))
  		return 0;
  
  	/*
  	 * check for the special corner case 'get_device_id' in the printer
  	 * class specification, where wIndex is (interface << 8 | altsetting)
  	 * instead of just interface
  	 */
  	if (requesttype == 0xa1 && request == 0) {
  		alt_setting = usb_find_alt_setting(ps->dev->actconfig,
  						   index >> 8, index & 0xff);
  		if (alt_setting
  		 && alt_setting->desc.bInterfaceClass == USB_CLASS_PRINTER)
  			index >>= 8;
  	}
  
  	index &= 0xff;
  	switch (requesttype & USB_RECIP_MASK) {
  	case USB_RECIP_ENDPOINT:
  		ret = findintfep(ps->dev, index);
  		if (ret >= 0)
  			ret = checkintf(ps, ret);
  		break;
  
  	case USB_RECIP_INTERFACE:
  		ret = checkintf(ps, index);
  		break;
  	}
  	return ret;
  }
  
  static int match_devt(struct device *dev, void *data)
  {
  	return dev->devt == (dev_t) (unsigned long) data;
  }
  
  static struct usb_device *usbdev_lookup_by_devt(dev_t devt)
  {
  	struct device *dev;
  
  	dev = bus_find_device(&usb_bus_type, NULL,
  			      (void *) (unsigned long) devt, match_devt);
  	if (!dev)
  		return NULL;
  	return container_of(dev, struct usb_device, dev);
  }
  
  /*
   * file operations
   */
  static int usbdev_open(struct inode *inode, struct file *file)
  {
  	struct usb_device *dev = NULL;
  	struct dev_state *ps;
  	int ret;
  
  	ret = -ENOMEM;
  	ps = kmalloc(sizeof(struct dev_state), GFP_KERNEL);
  	if (!ps)
  		goto out_free_ps;
  
  	ret = -ENODEV;
  
  	/* Protect against simultaneous removal or release */
  	mutex_lock(&usbfs_mutex);
  
  	/* usbdev device-node */
  	if (imajor(inode) == USB_DEVICE_MAJOR)
  		dev = usbdev_lookup_by_devt(inode->i_rdev);
  
  	mutex_unlock(&usbfs_mutex);
  
  	if (!dev)
  		goto out_free_ps;
  
  	usb_lock_device(dev);
  	if (dev->state == USB_STATE_NOTATTACHED)
  		goto out_unlock_device;
  
  	ret = usb_autoresume_device(dev);
  	if (ret)
  		goto out_unlock_device;
  
  	ps->dev = dev;
  	ps->file = file;
  	spin_lock_init(&ps->lock);
  	INIT_LIST_HEAD(&ps->list);
  	INIT_LIST_HEAD(&ps->async_pending);
  	INIT_LIST_HEAD(&ps->async_completed);
  	init_waitqueue_head(&ps->wait);
  	ps->discsignr = 0;
  	ps->disc_pid = get_pid(task_pid(current));
  	ps->cred = get_current_cred();
  	ps->disccontext = NULL;
  	ps->ifclaimed = 0;
  	security_task_getsecid(current, &ps->secid);
  	smp_wmb();
  	list_add_tail(&ps->list, &dev->filelist);
  	file->private_data = ps;
  	usb_unlock_device(dev);
  	snoop(&dev->dev, "opened by process %d: %s\n", task_pid_nr(current),
  			current->comm);
  	return ret;
  
   out_unlock_device:
  	usb_unlock_device(dev);
  	usb_put_dev(dev);
   out_free_ps:
  	kfree(ps);
  	return ret;
  }
  
  static int usbdev_release(struct inode *inode, struct file *file)
  {
  	struct dev_state *ps = file->private_data;
  	struct usb_device *dev = ps->dev;
  	unsigned int ifnum;
  	struct async *as;
  
  	usb_lock_device(dev);
  	usb_hub_release_all_ports(dev, ps);
  
  	list_del_init(&ps->list);
  
  	for (ifnum = 0; ps->ifclaimed && ifnum < 8*sizeof(ps->ifclaimed);
  			ifnum++) {
  		if (test_bit(ifnum, &ps->ifclaimed))
  			releaseintf(ps, ifnum);
  	}
  	destroy_all_async(ps);
  	usb_autosuspend_device(dev);
  	usb_unlock_device(dev);
  	usb_put_dev(dev);
  	put_pid(ps->disc_pid);
  	put_cred(ps->cred);
  
  	as = async_getcompleted(ps);
  	while (as) {
  		free_async(as);
  		as = async_getcompleted(ps);
  	}
  	kfree(ps);
  	return 0;
  }
  
  static int proc_control(struct dev_state *ps, void __user *arg)
  {
  	struct usb_device *dev = ps->dev;
  	struct usbdevfs_ctrltransfer ctrl;
  	unsigned int tmo;
  	unsigned char *tbuf;
  	unsigned wLength;
  	int i, pipe, ret;
  
  	if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
  		return -EFAULT;
  	ret = check_ctrlrecip(ps, ctrl.bRequestType, ctrl.bRequest,
  			      ctrl.wIndex);
  	if (ret)
  		return ret;
  	wLength = ctrl.wLength;		/* To suppress 64k PAGE_SIZE warning */
  	if (wLength > PAGE_SIZE)
  		return -EINVAL;
  	ret = usbfs_increase_memory_usage(PAGE_SIZE + sizeof(struct urb) +
  			sizeof(struct usb_ctrlrequest));
  	if (ret)
  		return ret;
  	tbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
  	if (!tbuf) {
  		ret = -ENOMEM;
  		goto done;
  	}
  	tmo = ctrl.timeout;
  	snoop(&dev->dev, "control urb: bRequestType=%02x "
  		"bRequest=%02x wValue=%04x "
  		"wIndex=%04x wLength=%04x\n",
  		ctrl.bRequestType, ctrl.bRequest,
  		__le16_to_cpup(&ctrl.wValue),
  		__le16_to_cpup(&ctrl.wIndex),
  		__le16_to_cpup(&ctrl.wLength));
  	if (ctrl.bRequestType & 0x80) {
  		if (ctrl.wLength && !access_ok(VERIFY_WRITE, ctrl.data,
  					       ctrl.wLength)) {
  			ret = -EINVAL;
  			goto done;
  		}
  		pipe = usb_rcvctrlpipe(dev, 0);
  		snoop_urb(dev, NULL, pipe, ctrl.wLength, tmo, SUBMIT, NULL, 0);
  
  		usb_unlock_device(dev);
  		i = usb_control_msg(dev, pipe, ctrl.bRequest,
  				    ctrl.bRequestType, ctrl.wValue, ctrl.wIndex,
  				    tbuf, ctrl.wLength, tmo);
  		usb_lock_device(dev);
  		snoop_urb(dev, NULL, pipe, max(i, 0), min(i, 0), COMPLETE,
  			  tbuf, max(i, 0));
  		if ((i > 0) && ctrl.wLength) {
  			if (copy_to_user(ctrl.data, tbuf, i)) {
  				ret = -EFAULT;
  				goto done;
  			}
  		}
  	} else {
  		if (ctrl.wLength) {
  			if (copy_from_user(tbuf, ctrl.data, ctrl.wLength)) {
  				ret = -EFAULT;
  				goto done;
  			}
  		}
  		pipe = usb_sndctrlpipe(dev, 0);
  		snoop_urb(dev, NULL, pipe, ctrl.wLength, tmo, SUBMIT,
  			tbuf, ctrl.wLength);
  
  		usb_unlock_device(dev);
  		i = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), ctrl.bRequest,
  				    ctrl.bRequestType, ctrl.wValue, ctrl.wIndex,
  				    tbuf, ctrl.wLength, tmo);
  		usb_lock_device(dev);
  		snoop_urb(dev, NULL, pipe, max(i, 0), min(i, 0), COMPLETE, NULL, 0);
  	}
  	if (i < 0 && i != -EPIPE) {
  		dev_printk(KERN_DEBUG, &dev->dev, "usbfs: USBDEVFS_CONTROL "
  			   "failed cmd %s rqt %u rq %u len %u ret %d\n",
  			   current->comm, ctrl.bRequestType, ctrl.bRequest,
  			   ctrl.wLength, i);
  	}
  	ret = i;
   done:
  	free_page((unsigned long) tbuf);
  	usbfs_decrease_memory_usage(PAGE_SIZE + sizeof(struct urb) +
  			sizeof(struct usb_ctrlrequest));
  	return ret;
  }
  
  static int proc_bulk(struct dev_state *ps, void __user *arg)
  {
  	struct usb_device *dev = ps->dev;
  	struct usbdevfs_bulktransfer bulk;
  	unsigned int tmo, len1, pipe;
  	int len2;
  	unsigned char *tbuf;
  	int i, ret;
  
  	if (copy_from_user(&bulk, arg, sizeof(bulk)))
  		return -EFAULT;
  	ret = findintfep(ps->dev, bulk.ep);
  	if (ret < 0)
  		return ret;
  	ret = checkintf(ps, ret);
  	if (ret)
  		return ret;
  	if (bulk.ep & USB_DIR_IN)
  		pipe = usb_rcvbulkpipe(dev, bulk.ep & 0x7f);
  	else
  		pipe = usb_sndbulkpipe(dev, bulk.ep & 0x7f);
  	if (!usb_maxpacket(dev, pipe, !(bulk.ep & USB_DIR_IN)))
  		return -EINVAL;
  	len1 = bulk.len;
  	if (len1 >= USBFS_XFER_MAX)
  		return -EINVAL;
  	ret = usbfs_increase_memory_usage(len1 + sizeof(struct urb));
  	if (ret)
  		return ret;
  	if (!(tbuf = kmalloc(len1, GFP_KERNEL))) {
  		ret = -ENOMEM;
  		goto done;
  	}
  	tmo = bulk.timeout;
  	if (bulk.ep & 0x80) {
  		if (len1 && !access_ok(VERIFY_WRITE, bulk.data, len1)) {
  			ret = -EINVAL;
  			goto done;
  		}
  		snoop_urb(dev, NULL, pipe, len1, tmo, SUBMIT, NULL, 0);
  
  		usb_unlock_device(dev);
  		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
  		usb_lock_device(dev);
  		snoop_urb(dev, NULL, pipe, len2, i, COMPLETE, tbuf, len2);
  
  		if (!i && len2) {
  			if (copy_to_user(bulk.data, tbuf, len2)) {
  				ret = -EFAULT;
  				goto done;
  			}
  		}
  	} else {
  		if (len1) {
  			if (copy_from_user(tbuf, bulk.data, len1)) {
  				ret = -EFAULT;
  				goto done;
  			}
  		}
  		snoop_urb(dev, NULL, pipe, len1, tmo, SUBMIT, tbuf, len1);
  
  		usb_unlock_device(dev);
  		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
  		usb_lock_device(dev);
  		snoop_urb(dev, NULL, pipe, len2, i, COMPLETE, NULL, 0);
  	}
  	ret = (i < 0 ? i : len2);
   done:
  	kfree(tbuf);
  	usbfs_decrease_memory_usage(len1 + sizeof(struct urb));
  	return ret;
  }
  
  static int proc_resetep(struct dev_state *ps, void __user *arg)
  {
  	unsigned int ep;
  	int ret;
  
  	if (get_user(ep, (unsigned int __user *)arg))
  		return -EFAULT;
  	ret = findintfep(ps->dev, ep);
  	if (ret < 0)
  		return ret;
  	ret = checkintf(ps, ret);
  	if (ret)
  		return ret;
  	usb_reset_endpoint(ps->dev, ep);
  	return 0;
  }
  
  static int proc_clearhalt(struct dev_state *ps, void __user *arg)
  {
  	unsigned int ep;
  	int pipe;
  	int ret;
  
  	if (get_user(ep, (unsigned int __user *)arg))
  		return -EFAULT;
  	ret = findintfep(ps->dev, ep);
  	if (ret < 0)
  		return ret;
  	ret = checkintf(ps, ret);
  	if (ret)
  		return ret;
  	if (ep & USB_DIR_IN)
  		pipe = usb_rcvbulkpipe(ps->dev, ep & 0x7f);
  	else
  		pipe = usb_sndbulkpipe(ps->dev, ep & 0x7f);
  
  	return usb_clear_halt(ps->dev, pipe);
  }
  
  static int proc_getdriver(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_getdriver gd;
  	struct usb_interface *intf;
  	int ret;
  
  	if (copy_from_user(&gd, arg, sizeof(gd)))
  		return -EFAULT;
  	intf = usb_ifnum_to_if(ps->dev, gd.interface);
  	if (!intf || !intf->dev.driver)
  		ret = -ENODATA;
  	else {
  		strncpy(gd.driver, intf->dev.driver->name,
  				sizeof(gd.driver));
  		ret = (copy_to_user(arg, &gd, sizeof(gd)) ? -EFAULT : 0);
  	}
  	return ret;
  }
  
  static int proc_connectinfo(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_connectinfo ci = {
  		.devnum = ps->dev->devnum,
  		.slow = ps->dev->speed == USB_SPEED_LOW
  	};
  
  	if (copy_to_user(arg, &ci, sizeof(ci)))
  		return -EFAULT;
  	return 0;
  }
  
  static int proc_resetdevice(struct dev_state *ps)
  {
  	return usb_reset_device(ps->dev);
  }
  
  static int proc_setintf(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_setinterface setintf;
  	int ret;
  
  	if (copy_from_user(&setintf, arg, sizeof(setintf)))
  		return -EFAULT;
  	if ((ret = checkintf(ps, setintf.interface)))
  		return ret;
  	return usb_set_interface(ps->dev, setintf.interface,
  			setintf.altsetting);
  }
  
  static int proc_setconfig(struct dev_state *ps, void __user *arg)
  {
  	int u;
  	int status = 0;
  	struct usb_host_config *actconfig;
  
  	if (get_user(u, (int __user *)arg))
  		return -EFAULT;
  
  	actconfig = ps->dev->actconfig;
  
  	/* Don't touch the device if any interfaces are claimed.
  	 * It could interfere with other drivers' operations, and if
  	 * an interface is claimed by usbfs it could easily deadlock.
  	 */
  	if (actconfig) {
  		int i;
  
  		for (i = 0; i < actconfig->desc.bNumInterfaces; ++i) {
  			if (usb_interface_claimed(actconfig->interface[i])) {
  				dev_warn(&ps->dev->dev,
  					"usbfs: interface %d claimed by %s "
  					"while '%s' sets config #%d\n",
  					actconfig->interface[i]
  						->cur_altsetting
  						->desc.bInterfaceNumber,
  					actconfig->interface[i]
  						->dev.driver->name,
  					current->comm, u);
  				status = -EBUSY;
  				break;
  			}
  		}
  	}
  
  	/* SET_CONFIGURATION is often abused as a "cheap" driver reset,
  	 * so avoid usb_set_configuration()'s kick to sysfs
  	 */
  	if (status == 0) {
  		if (actconfig && actconfig->desc.bConfigurationValue == u)
  			status = usb_reset_configuration(ps->dev);
  		else
  			status = usb_set_configuration(ps->dev, u);
  	}
  
  	return status;
  }
  
  static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
  			struct usbdevfs_iso_packet_desc __user *iso_frame_desc,
  			void __user *arg)
  {
  	struct usbdevfs_iso_packet_desc *isopkt = NULL;
  	struct usb_host_endpoint *ep;
  	struct async *as = NULL;
  	struct usb_ctrlrequest *dr = NULL;
  	unsigned int u, totlen, isofrmlen;
  	int i, ret, is_in, num_sgs = 0, ifnum = -1;
  	void *buf;
  
  	if (uurb->flags & ~(USBDEVFS_URB_ISO_ASAP |
  				USBDEVFS_URB_SHORT_NOT_OK |
  				USBDEVFS_URB_BULK_CONTINUATION |
  				USBDEVFS_URB_NO_FSBR |
  				USBDEVFS_URB_ZERO_PACKET |
  				USBDEVFS_URB_NO_INTERRUPT))
  		return -EINVAL;
  	if (uurb->buffer_length > 0 && !uurb->buffer)
  		return -EINVAL;
  	if (!(uurb->type == USBDEVFS_URB_TYPE_CONTROL &&
  	    (uurb->endpoint & ~USB_ENDPOINT_DIR_MASK) == 0)) {
  		ifnum = findintfep(ps->dev, uurb->endpoint);
  		if (ifnum < 0)
  			return ifnum;
  		ret = checkintf(ps, ifnum);
  		if (ret)
  			return ret;
  	}
  	if ((uurb->endpoint & USB_ENDPOINT_DIR_MASK) != 0) {
  		is_in = 1;
  		ep = ps->dev->ep_in[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
  	} else {
  		is_in = 0;
  		ep = ps->dev->ep_out[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
  	}
  	if (!ep)
  		return -ENOENT;
  
  	u = 0;
  	switch(uurb->type) {
  	case USBDEVFS_URB_TYPE_CONTROL:
  		if (!usb_endpoint_xfer_control(&ep->desc))
  			return -EINVAL;
  		/* min 8 byte setup packet */
  		if (uurb->buffer_length < 8)
  			return -EINVAL;
  		dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
  		if (!dr)
  			return -ENOMEM;
  		if (copy_from_user(dr, uurb->buffer, 8)) {
  			ret = -EFAULT;
  			goto error;
  		}
  		if (uurb->buffer_length < (le16_to_cpup(&dr->wLength) + 8)) {
  			ret = -EINVAL;
  			goto error;
  		}
  		ret = check_ctrlrecip(ps, dr->bRequestType, dr->bRequest,
  				      le16_to_cpup(&dr->wIndex));
  		if (ret)
  			goto error;
  		uurb->number_of_packets = 0;
  		uurb->buffer_length = le16_to_cpup(&dr->wLength);
  		uurb->buffer += 8;
  		if ((dr->bRequestType & USB_DIR_IN) && uurb->buffer_length) {
  			is_in = 1;
  			uurb->endpoint |= USB_DIR_IN;
  		} else {
  			is_in = 0;
  			uurb->endpoint &= ~USB_DIR_IN;
  		}
  		snoop(&ps->dev->dev, "control urb: bRequestType=%02x "
  			"bRequest=%02x wValue=%04x "
  			"wIndex=%04x wLength=%04x\n",
  			dr->bRequestType, dr->bRequest,
  			__le16_to_cpup(&dr->wValue),
  			__le16_to_cpup(&dr->wIndex),
  			__le16_to_cpup(&dr->wLength));
  		u = sizeof(struct usb_ctrlrequest);
  		break;
  
  	case USBDEVFS_URB_TYPE_BULK:
  		switch (usb_endpoint_type(&ep->desc)) {
  		case USB_ENDPOINT_XFER_CONTROL:
  		case USB_ENDPOINT_XFER_ISOC:
  			return -EINVAL;
  		case USB_ENDPOINT_XFER_INT:
  			/* allow single-shot interrupt transfers */
  			uurb->type = USBDEVFS_URB_TYPE_INTERRUPT;
  			goto interrupt_urb;
  		}
  		uurb->number_of_packets = 0;
  		num_sgs = DIV_ROUND_UP(uurb->buffer_length, USB_SG_SIZE);
  		if (num_sgs == 1 || num_sgs > ps->dev->bus->sg_tablesize)
  			num_sgs = 0;
  		break;
  
  	case USBDEVFS_URB_TYPE_INTERRUPT:
  		if (!usb_endpoint_xfer_int(&ep->desc))
  			return -EINVAL;
   interrupt_urb:
  		uurb->number_of_packets = 0;
  		break;
  
  	case USBDEVFS_URB_TYPE_ISO:
  		/* arbitrary limit */
  		if (uurb->number_of_packets < 1 ||
  		    uurb->number_of_packets > 128)
  			return -EINVAL;
  		if (!usb_endpoint_xfer_isoc(&ep->desc))
  			return -EINVAL;
  		isofrmlen = sizeof(struct usbdevfs_iso_packet_desc) *
  				   uurb->number_of_packets;
  		if (!(isopkt = kmalloc(isofrmlen, GFP_KERNEL)))
  			return -ENOMEM;
  		if (copy_from_user(isopkt, iso_frame_desc, isofrmlen)) {
  			ret = -EFAULT;
  			goto error;
  		}
  		for (totlen = u = 0; u < uurb->number_of_packets; u++) {
  			/* arbitrary limit,
  			 * sufficient for USB 2.0 high-bandwidth iso */
  			if (isopkt[u].length > 8192) {
  				ret = -EINVAL;
  				goto error;
  			}
  			totlen += isopkt[u].length;
  		}
  		u *= sizeof(struct usb_iso_packet_descriptor);
  		uurb->buffer_length = totlen;
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	if (uurb->buffer_length >= USBFS_XFER_MAX) {
  		ret = -EINVAL;
  		goto error;
  	}
  	if (uurb->buffer_length > 0 &&
  			!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ,
  				uurb->buffer, uurb->buffer_length)) {
  		ret = -EFAULT;
  		goto error;
  	}
  	as = alloc_async(uurb->number_of_packets);
  	if (!as) {
  		ret = -ENOMEM;
  		goto error;
  	}
  
  	u += sizeof(struct async) + sizeof(struct urb) + uurb->buffer_length +
  	     num_sgs * sizeof(struct scatterlist);
  	ret = usbfs_increase_memory_usage(u);
  	if (ret)
  		goto error;
  	as->mem_usage = u;
  
  	if (num_sgs) {
  		as->urb->sg = kmalloc(num_sgs * sizeof(struct scatterlist),
  				      GFP_KERNEL);
  		if (!as->urb->sg) {
  			ret = -ENOMEM;
  			goto error;
  		}
  		as->urb->num_sgs = num_sgs;
  		sg_init_table(as->urb->sg, as->urb->num_sgs);
  
  		totlen = uurb->buffer_length;
  		for (i = 0; i < as->urb->num_sgs; i++) {
  			u = (totlen > USB_SG_SIZE) ? USB_SG_SIZE : totlen;
  			buf = kmalloc(u, GFP_KERNEL);
  			if (!buf) {
  				ret = -ENOMEM;
  				goto error;
  			}
  			sg_set_buf(&as->urb->sg[i], buf, u);
  
  			if (!is_in) {
  				if (copy_from_user(buf, uurb->buffer, u)) {
  					ret = -EFAULT;
  					goto error;
  				}
  				uurb->buffer += u;
  			}
  			totlen -= u;
  		}
  	} else if (uurb->buffer_length > 0) {
  		as->urb->transfer_buffer = kmalloc(uurb->buffer_length,
  				GFP_KERNEL);
  		if (!as->urb->transfer_buffer) {
  			ret = -ENOMEM;
  			goto error;
  		}
  
  		if (!is_in) {
  			if (copy_from_user(as->urb->transfer_buffer,
  					   uurb->buffer,
  					   uurb->buffer_length)) {
  				ret = -EFAULT;
  				goto error;
  			}
  		} else if (uurb->type == USBDEVFS_URB_TYPE_ISO) {
  			/*
  			 * Isochronous input data may end up being
  			 * discontiguous if some of the packets are short.
  			 * Clear the buffer so that the gaps don't leak
  			 * kernel data to userspace.
  			 */
  			memset(as->urb->transfer_buffer, 0,
  					uurb->buffer_length);
  		}
  	}
  	as->urb->dev = ps->dev;
  	as->urb->pipe = (uurb->type << 30) |
  			__create_pipe(ps->dev, uurb->endpoint & 0xf) |
  			(uurb->endpoint & USB_DIR_IN);
  
  	/* This tedious sequence is necessary because the URB_* flags
  	 * are internal to the kernel and subject to change, whereas
  	 * the USBDEVFS_URB_* flags are a user API and must not be changed.
  	 */
  	u = (is_in ? URB_DIR_IN : URB_DIR_OUT);
  	if (uurb->flags & USBDEVFS_URB_ISO_ASAP)
  		u |= URB_ISO_ASAP;
  	if (uurb->flags & USBDEVFS_URB_SHORT_NOT_OK)
  		u |= URB_SHORT_NOT_OK;
  	if (uurb->flags & USBDEVFS_URB_NO_FSBR)
  		u |= URB_NO_FSBR;
  	if (uurb->flags & USBDEVFS_URB_ZERO_PACKET)
  		u |= URB_ZERO_PACKET;
  	if (uurb->flags & USBDEVFS_URB_NO_INTERRUPT)
  		u |= URB_NO_INTERRUPT;
  	as->urb->transfer_flags = u;
  
  	as->urb->transfer_buffer_length = uurb->buffer_length;
  	as->urb->setup_packet = (unsigned char *)dr;
  	dr = NULL;
  	as->urb->start_frame = uurb->start_frame;
  	as->urb->number_of_packets = uurb->number_of_packets;
  	if (uurb->type == USBDEVFS_URB_TYPE_ISO ||
  			ps->dev->speed == USB_SPEED_HIGH)
  		as->urb->interval = 1 << min(15, ep->desc.bInterval - 1);
  	else
  		as->urb->interval = ep->desc.bInterval;
  	as->urb->context = as;
  	as->urb->complete = async_completed;
  	for (totlen = u = 0; u < uurb->number_of_packets; u++) {
  		as->urb->iso_frame_desc[u].offset = totlen;
  		as->urb->iso_frame_desc[u].length = isopkt[u].length;
  		totlen += isopkt[u].length;
  	}
  	kfree(isopkt);
  	isopkt = NULL;
  	as->ps = ps;
  	as->userurb = arg;
  	if (is_in && uurb->buffer_length > 0)
  		as->userbuffer = uurb->buffer;
  	else
  		as->userbuffer = NULL;
  	as->signr = uurb->signr;
  	as->ifnum = ifnum;
  	as->pid = get_pid(task_pid(current));
  	as->cred = get_current_cred();
  	security_task_getsecid(current, &as->secid);
  	snoop_urb(ps->dev, as->userurb, as->urb->pipe,
  			as->urb->transfer_buffer_length, 0, SUBMIT,
  			NULL, 0);
  	if (!is_in)
  		snoop_urb_data(as->urb, as->urb->transfer_buffer_length);
  
  	async_newpending(as);
  
  	if (usb_endpoint_xfer_bulk(&ep->desc)) {
  		spin_lock_irq(&ps->lock);
  
  		/* Not exactly the endpoint address; the direction bit is
  		 * shifted to the 0x10 position so that the value will be
  		 * between 0 and 31.
  		 */
  		as->bulk_addr = usb_endpoint_num(&ep->desc) |
  			((ep->desc.bEndpointAddress & USB_ENDPOINT_DIR_MASK)
  				>> 3);
  
  		/* If this bulk URB is the start of a new transfer, re-enable
  		 * the endpoint.  Otherwise mark it as a continuation URB.
  		 */
  		if (uurb->flags & USBDEVFS_URB_BULK_CONTINUATION)
  			as->bulk_status = AS_CONTINUATION;
  		else
  			ps->disabled_bulk_eps &= ~(1 << as->bulk_addr);
  
  		/* Don't accept continuation URBs if the endpoint is
  		 * disabled because of an earlier error.
  		 */
  		if (ps->disabled_bulk_eps & (1 << as->bulk_addr))
  			ret = -EREMOTEIO;
  		else
  			ret = usb_submit_urb(as->urb, GFP_ATOMIC);
  		spin_unlock_irq(&ps->lock);
  	} else {
  		ret = usb_submit_urb(as->urb, GFP_KERNEL);
  	}
  
  	if (ret) {
  		dev_printk(KERN_DEBUG, &ps->dev->dev,
  			   "usbfs: usb_submit_urb returned %d\n", ret);
  		snoop_urb(ps->dev, as->userurb, as->urb->pipe,
  				0, ret, COMPLETE, NULL, 0);
  		async_removepending(as);
  		goto error;
  	}
  	return 0;
  
   error:
  	kfree(isopkt);
  	kfree(dr);
  	if (as)
  		free_async(as);
  	return ret;
  }
  
  static int proc_submiturb(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_urb uurb;
  
  	if (copy_from_user(&uurb, arg, sizeof(uurb)))
  		return -EFAULT;
  
  	return proc_do_submiturb(ps, &uurb,
  			(((struct usbdevfs_urb __user *)arg)->iso_frame_desc),
  			arg);
  }
  
  static int proc_unlinkurb(struct dev_state *ps, void __user *arg)
  {
  	struct urb *urb;
  	struct async *as;
  	unsigned long flags;
  
  	spin_lock_irqsave(&ps->lock, flags);
  	as = async_getpending(ps, arg);
  	if (!as) {
  		spin_unlock_irqrestore(&ps->lock, flags);
  		return -EINVAL;
  	}
  
  	urb = as->urb;
  	usb_get_urb(urb);
  	spin_unlock_irqrestore(&ps->lock, flags);
  
  	usb_kill_urb(urb);
  	usb_put_urb(urb);
  
  	return 0;
  }
  
  static int processcompl(struct async *as, void __user * __user *arg)
  {
  	struct urb *urb = as->urb;
  	struct usbdevfs_urb __user *userurb = as->userurb;
  	void __user *addr = as->userurb;
  	unsigned int i;
  
  	if (as->userbuffer && urb->actual_length) {
  		if (copy_urb_data_to_user(as->userbuffer, urb))
  			goto err_out;
  	}
  	if (put_user(as->status, &userurb->status))
  		goto err_out;
  	if (put_user(urb->actual_length, &userurb->actual_length))
  		goto err_out;
  	if (put_user(urb->error_count, &userurb->error_count))
  		goto err_out;
  
  	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
  		for (i = 0; i < urb->number_of_packets; i++) {
  			if (put_user(urb->iso_frame_desc[i].actual_length,
  				     &userurb->iso_frame_desc[i].actual_length))
  				goto err_out;
  			if (put_user(urb->iso_frame_desc[i].status,
  				     &userurb->iso_frame_desc[i].status))
  				goto err_out;
  		}
  	}
  
  	if (put_user(addr, (void __user * __user *)arg))
  		return -EFAULT;
  	return 0;
  
  err_out:
  	return -EFAULT;
  }
  
  static struct async *reap_as(struct dev_state *ps)
  {
  	DECLARE_WAITQUEUE(wait, current);
  	struct async *as = NULL;
  	struct usb_device *dev = ps->dev;
  
  	add_wait_queue(&ps->wait, &wait);
  	for (;;) {
  		__set_current_state(TASK_INTERRUPTIBLE);
  		as = async_getcompleted(ps);
  		if (as)
  			break;
  		if (signal_pending(current))
  			break;
  		usb_unlock_device(dev);
  		schedule();
  		usb_lock_device(dev);
  	}
  	remove_wait_queue(&ps->wait, &wait);
  	set_current_state(TASK_RUNNING);
  	return as;
  }
  
  static int proc_reapurb(struct dev_state *ps, void __user *arg)
  {
  	struct async *as = reap_as(ps);
  	if (as) {
  		int retval = processcompl(as, (void __user * __user *)arg);
  		free_async(as);
  		return retval;
  	}
  	if (signal_pending(current))
  		return -EINTR;
  	return -EIO;
  }
  
  static int proc_reapurbnonblock(struct dev_state *ps, void __user *arg)
  {
  	int retval;
  	struct async *as;
  
  	as = async_getcompleted(ps);
  	retval = -EAGAIN;
  	if (as) {
  		retval = processcompl(as, (void __user * __user *)arg);
  		free_async(as);
  	}
  	return retval;
  }
  
  #ifdef CONFIG_COMPAT
  static int proc_control_compat(struct dev_state *ps,
  				struct usbdevfs_ctrltransfer32 __user *p32)
  {
          struct usbdevfs_ctrltransfer __user *p;
          __u32 udata;
          p = compat_alloc_user_space(sizeof(*p));
          if (copy_in_user(p, p32, (sizeof(*p32) - sizeof(compat_caddr_t))) ||
              get_user(udata, &p32->data) ||
  	    put_user(compat_ptr(udata), &p->data))
  		return -EFAULT;
          return proc_control(ps, p);
  }
  
  static int proc_bulk_compat(struct dev_state *ps,
  			struct usbdevfs_bulktransfer32 __user *p32)
  {
          struct usbdevfs_bulktransfer __user *p;
          compat_uint_t n;
          compat_caddr_t addr;
  
          p = compat_alloc_user_space(sizeof(*p));
  
          if (get_user(n, &p32->ep) || put_user(n, &p->ep) ||
              get_user(n, &p32->len) || put_user(n, &p->len) ||
              get_user(n, &p32->timeout) || put_user(n, &p->timeout) ||
              get_user(addr, &p32->data) || put_user(compat_ptr(addr), &p->data))
                  return -EFAULT;
  
          return proc_bulk(ps, p);
  }
  static int proc_disconnectsignal_compat(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_disconnectsignal32 ds;
  
  	if (copy_from_user(&ds, arg, sizeof(ds)))
  		return -EFAULT;
  	ps->discsignr = ds.signr;
  	ps->disccontext = compat_ptr(ds.context);
  	return 0;
  }
  
  static int get_urb32(struct usbdevfs_urb *kurb,
  		     struct usbdevfs_urb32 __user *uurb)
  {
  	__u32  uptr;
  	if (!access_ok(VERIFY_READ, uurb, sizeof(*uurb)) ||
  	    __get_user(kurb->type, &uurb->type) ||
  	    __get_user(kurb->endpoint, &uurb->endpoint) ||
  	    __get_user(kurb->status, &uurb->status) ||
  	    __get_user(kurb->flags, &uurb->flags) ||
  	    __get_user(kurb->buffer_length, &uurb->buffer_length) ||
  	    __get_user(kurb->actual_length, &uurb->actual_length) ||
  	    __get_user(kurb->start_frame, &uurb->start_frame) ||
  	    __get_user(kurb->number_of_packets, &uurb->number_of_packets) ||
  	    __get_user(kurb->error_count, &uurb->error_count) ||
  	    __get_user(kurb->signr, &uurb->signr))
  		return -EFAULT;
  
  	if (__get_user(uptr, &uurb->buffer))
  		return -EFAULT;
  	kurb->buffer = compat_ptr(uptr);
  	if (__get_user(uptr, &uurb->usercontext))
  		return -EFAULT;
  	kurb->usercontext = compat_ptr(uptr);
  
  	return 0;
  }
  
  static int proc_submiturb_compat(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_urb uurb;
  
  	if (get_urb32(&uurb, (struct usbdevfs_urb32 __user *)arg))
  		return -EFAULT;
  
  	return proc_do_submiturb(ps, &uurb,
  			((struct usbdevfs_urb32 __user *)arg)->iso_frame_desc,
  			arg);
  }
  
  static int processcompl_compat(struct async *as, void __user * __user *arg)
  {
  	struct urb *urb = as->urb;
  	struct usbdevfs_urb32 __user *userurb = as->userurb;
  	void __user *addr = as->userurb;
  	unsigned int i;
  
  	if (as->userbuffer && urb->actual_length) {
  		if (copy_urb_data_to_user(as->userbuffer, urb))
  			return -EFAULT;
  	}
  	if (put_user(as->status, &userurb->status))
  		return -EFAULT;
  	if (put_user(urb->actual_length, &userurb->actual_length))
  		return -EFAULT;
  	if (put_user(urb->error_count, &userurb->error_count))
  		return -EFAULT;
  
  	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
  		for (i = 0; i < urb->number_of_packets; i++) {
  			if (put_user(urb->iso_frame_desc[i].actual_length,
  				     &userurb->iso_frame_desc[i].actual_length))
  				return -EFAULT;
  			if (put_user(urb->iso_frame_desc[i].status,
  				     &userurb->iso_frame_desc[i].status))
  				return -EFAULT;
  		}
  	}
  
  	if (put_user(ptr_to_compat(addr), (u32 __user *)arg))
  		return -EFAULT;
  	return 0;
  }
  
  static int proc_reapurb_compat(struct dev_state *ps, void __user *arg)
  {
  	struct async *as = reap_as(ps);
  	if (as) {
  		int retval = processcompl_compat(as, (void __user * __user *)arg);
  		free_async(as);
  		return retval;
  	}
  	if (signal_pending(current))
  		return -EINTR;
  	return -EIO;
  }
  
  static int proc_reapurbnonblock_compat(struct dev_state *ps, void __user *arg)
  {
  	int retval;
  	struct async *as;
  
  	retval = -EAGAIN;
  	as = async_getcompleted(ps);
  	if (as) {
  		retval = processcompl_compat(as, (void __user * __user *)arg);
  		free_async(as);
  	}
  	return retval;
  }
  
  
  #endif
  
  static int proc_disconnectsignal(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_disconnectsignal ds;
  
  	if (copy_from_user(&ds, arg, sizeof(ds)))
  		return -EFAULT;
  	ps->discsignr = ds.signr;
  	ps->disccontext = ds.context;
  	return 0;
  }
  
  static int proc_claiminterface(struct dev_state *ps, void __user *arg)
  {
  	unsigned int ifnum;
  
  	if (get_user(ifnum, (unsigned int __user *)arg))
  		return -EFAULT;
  	return claimintf(ps, ifnum);
  }
  
  static int proc_releaseinterface(struct dev_state *ps, void __user *arg)
  {
  	unsigned int ifnum;
  	int ret;
  
  	if (get_user(ifnum, (unsigned int __user *)arg))
  		return -EFAULT;
  	if ((ret = releaseintf(ps, ifnum)) < 0)
  		return ret;
  	destroy_async_on_interface (ps, ifnum);
  	return 0;
  }
  
  static int proc_ioctl(struct dev_state *ps, struct usbdevfs_ioctl *ctl)
  {
  	int			size;
  	void			*buf = NULL;
  	int			retval = 0;
  	struct usb_interface    *intf = NULL;
  	struct usb_driver       *driver = NULL;
  
  	/* alloc buffer */
  	if ((size = _IOC_SIZE(ctl->ioctl_code)) > 0) {
  		if ((buf = kmalloc(size, GFP_KERNEL)) == NULL)
  			return -ENOMEM;
  		if ((_IOC_DIR(ctl->ioctl_code) & _IOC_WRITE)) {
  			if (copy_from_user(buf, ctl->data, size)) {
  				kfree(buf);
  				return -EFAULT;
  			}
  		} else {
  			memset(buf, 0, size);
  		}
  	}
  
  	if (!connected(ps)) {
  		kfree(buf);
  		return -ENODEV;
  	}
  
  	if (ps->dev->state != USB_STATE_CONFIGURED)
  		retval = -EHOSTUNREACH;
  	else if (!(intf = usb_ifnum_to_if(ps->dev, ctl->ifno)))
  		retval = -EINVAL;
  	else switch (ctl->ioctl_code) {
  
  	/* disconnect kernel driver from interface */
  	case USBDEVFS_DISCONNECT:
  		if (intf->dev.driver) {
  			driver = to_usb_driver(intf->dev.driver);
  			dev_dbg(&intf->dev, "disconnect by usbfs\n");
  			usb_driver_release_interface(driver, intf);
  		} else
  			retval = -ENODATA;
  		break;
  
  	/* let kernel drivers try to (re)bind to the interface */
  	case USBDEVFS_CONNECT:
  		if (!intf->dev.driver)
  			retval = device_attach(&intf->dev);
  		else
  			retval = -EBUSY;
  		break;
  
  	/* talk directly to the interface's driver */
  	default:
  		if (intf->dev.driver)
  			driver = to_usb_driver(intf->dev.driver);
  		if (driver == NULL || driver->unlocked_ioctl == NULL) {
  			retval = -ENOTTY;
  		} else {
  			retval = driver->unlocked_ioctl(intf, ctl->ioctl_code, buf);
  			if (retval == -ENOIOCTLCMD)
  				retval = -ENOTTY;
  		}
  	}
  
  	/* cleanup and return */
  	if (retval >= 0
  			&& (_IOC_DIR(ctl->ioctl_code) & _IOC_READ) != 0
  			&& size > 0
  			&& copy_to_user(ctl->data, buf, size) != 0)
  		retval = -EFAULT;
  
  	kfree(buf);
  	return retval;
  }
  
  static int proc_ioctl_default(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_ioctl	ctrl;
  
  	if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
  		return -EFAULT;
  	return proc_ioctl(ps, &ctrl);
  }
  
  #ifdef CONFIG_COMPAT
  static int proc_ioctl_compat(struct dev_state *ps, compat_uptr_t arg)
  {
  	struct usbdevfs_ioctl32 __user *uioc;
  	struct usbdevfs_ioctl ctrl;
  	u32 udata;
  
  	uioc = compat_ptr((long)arg);
  	if (!access_ok(VERIFY_READ, uioc, sizeof(*uioc)) ||
  	    __get_user(ctrl.ifno, &uioc->ifno) ||
  	    __get_user(ctrl.ioctl_code, &uioc->ioctl_code) ||
  	    __get_user(udata, &uioc->data))
  		return -EFAULT;
  	ctrl.data = compat_ptr(udata);
  
  	return proc_ioctl(ps, &ctrl);
  }
  #endif
  
  static int proc_claim_port(struct dev_state *ps, void __user *arg)
  {
  	unsigned portnum;
  	int rc;
  
  	if (get_user(portnum, (unsigned __user *) arg))
  		return -EFAULT;
  	rc = usb_hub_claim_port(ps->dev, portnum, ps);
  	if (rc == 0)
  		snoop(&ps->dev->dev, "port %d claimed by process %d: %s\n",
  			portnum, task_pid_nr(current), current->comm);
  	return rc;
  }
  
  static int proc_release_port(struct dev_state *ps, void __user *arg)
  {
  	unsigned portnum;
  
  	if (get_user(portnum, (unsigned __user *) arg))
  		return -EFAULT;
  	return usb_hub_release_port(ps->dev, portnum, ps);
  }
  
  static int proc_get_capabilities(struct dev_state *ps, void __user *arg)
  {
  	__u32 caps;
  
  	caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM;
  	if (!ps->dev->bus->no_stop_on_short)
  		caps |= USBDEVFS_CAP_BULK_CONTINUATION;
  	if (ps->dev->bus->sg_tablesize)
  		caps |= USBDEVFS_CAP_BULK_SCATTER_GATHER;
  
  	if (put_user(caps, (__u32 __user *)arg))
  		return -EFAULT;
  
  	return 0;
  }
  
  static int proc_disconnect_claim(struct dev_state *ps, void __user *arg)
  {
  	struct usbdevfs_disconnect_claim dc;
  	struct usb_interface *intf;
  
  	if (copy_from_user(&dc, arg, sizeof(dc)))
  		return -EFAULT;
  
  	intf = usb_ifnum_to_if(ps->dev, dc.interface);
  	if (!intf)
  		return -EINVAL;
  
  	if (intf->dev.driver) {
  		struct usb_driver *driver = to_usb_driver(intf->dev.driver);
  
  		if ((dc.flags & USBDEVFS_DISCONNECT_CLAIM_IF_DRIVER) &&
  				strncmp(dc.driver, intf->dev.driver->name,
  					sizeof(dc.driver)) != 0)
  			return -EBUSY;
  
  		if ((dc.flags & USBDEVFS_DISCONNECT_CLAIM_EXCEPT_DRIVER) &&
  				strncmp(dc.driver, intf->dev.driver->name,
  					sizeof(dc.driver)) == 0)
  			return -EBUSY;
  
  		dev_dbg(&intf->dev, "disconnect by usbfs\n");
  		usb_driver_release_interface(driver, intf);
  	}
  
  	return claimintf(ps, dc.interface);
  }
  
  /*
   * NOTE:  All requests here that have interface numbers as parameters
   * are assuming that somehow the configuration has been prevented from
   * changing.  But there's no mechanism to ensure that...
   */
  static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
  				void __user *p)
  {
  	struct dev_state *ps = file->private_data;
  	struct inode *inode = file->f_path.dentry->d_inode;
  	struct usb_device *dev = ps->dev;
  	int ret = -ENOTTY;
  
  	if (!(file->f_mode & FMODE_WRITE))
  		return -EPERM;
  
  	usb_lock_device(dev);
  	if (!connected(ps)) {
  		usb_unlock_device(dev);
  		return -ENODEV;
  	}
  
  	switch (cmd) {
  	case USBDEVFS_CONTROL:
  		snoop(&dev->dev, "%s: CONTROL\n", __func__);
  		ret = proc_control(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_BULK:
  		snoop(&dev->dev, "%s: BULK\n", __func__);
  		ret = proc_bulk(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_RESETEP:
  		snoop(&dev->dev, "%s: RESETEP\n", __func__);
  		ret = proc_resetep(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_RESET:
  		snoop(&dev->dev, "%s: RESET\n", __func__);
  		ret = proc_resetdevice(ps);
  		break;
  
  	case USBDEVFS_CLEAR_HALT:
  		snoop(&dev->dev, "%s: CLEAR_HALT\n", __func__);
  		ret = proc_clearhalt(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_GETDRIVER:
  		snoop(&dev->dev, "%s: GETDRIVER\n", __func__);
  		ret = proc_getdriver(ps, p);
  		break;
  
  	case USBDEVFS_CONNECTINFO:
  		snoop(&dev->dev, "%s: CONNECTINFO\n", __func__);
  		ret = proc_connectinfo(ps, p);
  		break;
  
  	case USBDEVFS_SETINTERFACE:
  		snoop(&dev->dev, "%s: SETINTERFACE\n", __func__);
  		ret = proc_setintf(ps, p);
  		break;
  
  	case USBDEVFS_SETCONFIGURATION:
  		snoop(&dev->dev, "%s: SETCONFIGURATION\n", __func__);
  		ret = proc_setconfig(ps, p);
  		break;
  
  	case USBDEVFS_SUBMITURB:
  		snoop(&dev->dev, "%s: SUBMITURB\n", __func__);
  		ret = proc_submiturb(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  #ifdef CONFIG_COMPAT
  	case USBDEVFS_CONTROL32:
  		snoop(&dev->dev, "%s: CONTROL32\n", __func__);
  		ret = proc_control_compat(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_BULK32:
  		snoop(&dev->dev, "%s: BULK32\n", __func__);
  		ret = proc_bulk_compat(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_DISCSIGNAL32:
  		snoop(&dev->dev, "%s: DISCSIGNAL32\n", __func__);
  		ret = proc_disconnectsignal_compat(ps, p);
  		break;
  
  	case USBDEVFS_SUBMITURB32:
  		snoop(&dev->dev, "%s: SUBMITURB32\n", __func__);
  		ret = proc_submiturb_compat(ps, p);
  		if (ret >= 0)
  			inode->i_mtime = CURRENT_TIME;
  		break;
  
  	case USBDEVFS_REAPURB32:
  		snoop(&dev->dev, "%s: REAPURB32\n", __func__);
  		ret = proc_reapurb_compat(ps, p);
  		break;
  
  	case USBDEVFS_REAPURBNDELAY32:
  		snoop(&dev->dev, "%s: REAPURBNDELAY32\n", __func__);
  		ret = proc_reapurbnonblock_compat(ps, p);
  		break;
  
  	case USBDEVFS_IOCTL32:
  		snoop(&dev->dev, "%s: IOCTL32\n", __func__);
  		ret = proc_ioctl_compat(ps, ptr_to_compat(p));
  		break;
  #endif
  
  	case USBDEVFS_DISCARDURB:
  		snoop(&dev->dev, "%s: DISCARDURB\n", __func__);
  		ret = proc_unlinkurb(ps, p);
  		break;
  
  	case USBDEVFS_REAPURB:
  		snoop(&dev->dev, "%s: REAPURB\n", __func__);
  		ret = proc_reapurb(ps, p);
  		break;
  
  	case USBDEVFS_REAPURBNDELAY:
  		snoop(&dev->dev, "%s: REAPURBNDELAY\n", __func__);
  		ret = proc_reapurbnonblock(ps, p);
  		break;
  
  	case USBDEVFS_DISCSIGNAL:
  		snoop(&dev->dev, "%s: DISCSIGNAL\n", __func__);
  		ret = proc_disconnectsignal(ps, p);
  		break;
  
  	case USBDEVFS_CLAIMINTERFACE:
  		snoop(&dev->dev, "%s: CLAIMINTERFACE\n", __func__);
  		ret = proc_claiminterface(ps, p);
  		break;
  
  	case USBDEVFS_RELEASEINTERFACE:
  		snoop(&dev->dev, "%s: RELEASEINTERFACE\n", __func__);
  		ret = proc_releaseinterface(ps, p);
  		break;
  
  	case USBDEVFS_IOCTL:
  		snoop(&dev->dev, "%s: IOCTL\n", __func__);
  		ret = proc_ioctl_default(ps, p);
  		break;
  
  	case USBDEVFS_CLAIM_PORT:
  		snoop(&dev->dev, "%s: CLAIM_PORT\n", __func__);
  		ret = proc_claim_port(ps, p);
  		break;
  
  	case USBDEVFS_RELEASE_PORT:
  		snoop(&dev->dev, "%s: RELEASE_PORT\n", __func__);
  		ret = proc_release_port(ps, p);
  		break;
  	case USBDEVFS_GET_CAPABILITIES:
  		ret = proc_get_capabilities(ps, p);
  		break;
  	case USBDEVFS_DISCONNECT_CLAIM:
  		ret = proc_disconnect_claim(ps, p);
  		break;
  	}
  	usb_unlock_device(dev);
  	if (ret >= 0)
  		inode->i_atime = CURRENT_TIME;
  	return ret;
  }
  
  static long usbdev_ioctl(struct file *file, unsigned int cmd,
  			unsigned long arg)
  {
  	int ret;
  
  	ret = usbdev_do_ioctl(file, cmd, (void __user *)arg);
  
  	return ret;
  }
  
  #ifdef CONFIG_COMPAT
  static long usbdev_compat_ioctl(struct file *file, unsigned int cmd,
  			unsigned long arg)
  {
  	int ret;
  
  	ret = usbdev_do_ioctl(file, cmd, compat_ptr(arg));
  
  	return ret;
  }
  #endif
  
  /* No kernel lock - fine */
  static unsigned int usbdev_poll(struct file *file,
  				struct poll_table_struct *wait)
  {
  	struct dev_state *ps = file->private_data;
  	unsigned int mask = 0;
  
  	poll_wait(file, &ps->wait, wait);
  	if (file->f_mode & FMODE_WRITE && !list_empty(&ps->async_completed))
  		mask |= POLLOUT | POLLWRNORM;
  	if (!connected(ps))
  		mask |= POLLERR | POLLHUP;
  	return mask;
  }
  
  const struct file_operations usbdev_file_operations = {
  	.owner =	  THIS_MODULE,
  	.llseek =	  usbdev_lseek,
  	.read =		  usbdev_read,
  	.poll =		  usbdev_poll,
  	.unlocked_ioctl = usbdev_ioctl,
  #ifdef CONFIG_COMPAT
  	.compat_ioctl =   usbdev_compat_ioctl,
  #endif
  	.open =		  usbdev_open,
  	.release =	  usbdev_release,
  };
  
  static void usbdev_remove(struct usb_device *udev)
  {
  	struct dev_state *ps;
  	struct siginfo sinfo;
  
  	while (!list_empty(&udev->filelist)) {
  		ps = list_entry(udev->filelist.next, struct dev_state, list);
  		destroy_all_async(ps);
  		wake_up_all(&ps->wait);
  		list_del_init(&ps->list);
  		if (ps->discsignr) {
  			sinfo.si_signo = ps->discsignr;
  			sinfo.si_errno = EPIPE;
  			sinfo.si_code = SI_ASYNCIO;
  			sinfo.si_addr = ps->disccontext;
  			kill_pid_info_as_cred(ps->discsignr, &sinfo,
  					ps->disc_pid, ps->cred, ps->secid);
  		}
  	}
  }
  
  static int usbdev_notify(struct notifier_block *self,
  			       unsigned long action, void *dev)
  {
  	switch (action) {
  	case USB_DEVICE_ADD:
  		break;
  	case USB_DEVICE_REMOVE:
  		usbdev_remove(dev);
  		break;
  	}
  	return NOTIFY_OK;
  }
  
  static struct notifier_block usbdev_nb = {
  	.notifier_call = 	usbdev_notify,
  };
  
  static struct cdev usb_device_cdev;
  
  int __init usb_devio_init(void)
  {
  	int retval;
  
  	retval = register_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX,
  					"usb_device");
  	if (retval) {
  		printk(KERN_ERR "Unable to register minors for usb_device\n");
  		goto out;
  	}
  	cdev_init(&usb_device_cdev, &usbdev_file_operations);
  	retval = cdev_add(&usb_device_cdev, USB_DEVICE_DEV, USB_DEVICE_MAX);
  	if (retval) {
  		printk(KERN_ERR "Unable to get usb_device major %d\n",
  		       USB_DEVICE_MAJOR);
  		goto error_cdev;
  	}
  	usb_register_notify(&usbdev_nb);
  out:
  	return retval;
  
  error_cdev:
  	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
  	goto out;
  }
  
  void usb_devio_cleanup(void)
  {
  	usb_unregister_notify(&usbdev_nb);
  	cdev_del(&usb_device_cdev);
  	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
  }
  