net/core/wireless.c - pub/scm/linux/kernel/git/tglx/history - Git at Google

 /*
  * This file implement the Wireless Extensions APIs.
  *
  * Authors :	Jean Tourrilhes - HPL - <jt@hpl.hp.com>
  * Copyright (c) 1997-2001 Jean Tourrilhes, All Rights Reserved.
  *
  * (As all part of the Linux kernel, this file is GPL)
  */

 /************************** DOCUMENTATION **************************/
 /*
  * API definition :
  * --------------
  * See <linux/wireless.h> for details of the APIs and the rest.
  *
  * History :
  * -------
  *
  * v1 - 5.12.01 - Jean II
  *	o Created this file.
  *
  * v2 - 13.12.01 - Jean II
  *	o Move /proc/net/wireless stuff from net/core/dev.c to here
  *	o Make Wireless Extension IOCTLs go through here
  *	o Added iw_handler handling ;-)
  *	o Added standard ioctl description
  *	o Initial dumb commit strategy based on orinoco.c
  */

 /***************************** INCLUDES *****************************/

 #include <asm/uaccess.h>		/* copy_to_user() */
 #include <linux/config.h>		/* Not needed ??? */
 #include <linux/types.h>		/* off_t */
 #include <linux/netdevice.h>		/* struct ifreq, dev_get_by_name() */

 #include <linux/wireless.h>		/* Pretty obvious */
 #include <net/iw_handler.h>		/* New driver API */

 /**************************** CONSTANTS ****************************/

 /* This will be turned on later on... */
 #undef WE_STRICT_WRITE		/* Check write buffer size */

 /* Debuging stuff */
 #undef WE_IOCTL_DEBUG		/* Debug IOCTL API */

 /************************* GLOBAL VARIABLES *************************/
 /*
  * You should not use global variables, because or re-entrancy.
  * On our case, it's only const, so it's OK...
  */
 static const struct iw_ioctl_description	standard_ioctl[] = {
 	/* SIOCSIWCOMMIT (internal) */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCGIWNAME */
 	{ IW_HEADER_TYPE_CHAR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWNWID */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
 	/* SIOCGIWNWID */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWFREQ */
 	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
 	/* SIOCGIWFREQ */
 	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWMODE */
 	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
 	/* SIOCGIWMODE */
 	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWSENS */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWSENS */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWRANGE */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCGIWRANGE */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, sizeof(struct iw_range), IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWPRIV */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCGIWPRIV (handled directly by us) */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCSIWSTATS */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCGIWSTATS (handled directly by us) */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWSPY */
 	{ IW_HEADER_TYPE_POINT, 0, sizeof(struct sockaddr), 0, IW_MAX_SPY, 0},
 	/* SIOCGIWSPY */
 	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_SPY, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCSIWAP */
 	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, 0},
 	/* SIOCGIWAP */
 	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCGIWAPLIST */
 	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_AP, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCSIWESSID */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_EVENT},
 	/* SIOCGIWESSID */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_DUMP},
 	/* SIOCSIWNICKN */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
 	/* SIOCGIWNICKN */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* -- hole -- */
 	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
 	/* SIOCSIWRATE */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWRATE */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWRTS */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWRTS */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWFRAG */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWFRAG */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWTXPOW */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWTXPOW */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWRETRY */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWRETRY */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCSIWENCODE */
 	{ IW_HEADER_TYPE_POINT, 4, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT},
 	/* SIOCGIWENCODE */
 	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT},
 	/* SIOCSIWPOWER */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 	/* SIOCGIWPOWER */
 	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
 };

 /* Size (in bytes) of the various private data types */
 char priv_type_size[] = { 0, 1, 1, 0, 4, 4, 0, 0 };

 /************************ COMMON SUBROUTINES ************************/
 /*
  * Stuff that may be used in various place or doesn't fit in one
  * of the section below.
  */

 /* ---------------------------------------------------------------- */
 /*
  * Return the driver handler associated with a specific Wireless Extension.
  * Called from various place, so make sure it remains efficient.
  */
 static inline iw_handler get_handler(struct net_device *dev,
 				     unsigned int cmd)
 {
 	unsigned int	index;		/* MUST be unsigned */

 	/* Check if we have some wireless handlers defined */
 	if(dev->wireless_handlers == NULL)
 		return NULL;

 	/* Try as a standard command */
 	index = cmd - SIOCIWFIRST;
 	if(index < dev->wireless_handlers->num_standard)
 		return dev->wireless_handlers->standard[index];

 	/* Try as a private command */
 	index = cmd - SIOCIWFIRSTPRIV;
 	if(index < dev->wireless_handlers->num_private)
 		return dev->wireless_handlers->private[index];

 	/* Not found */
 	return NULL;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Get statistics out of the driver
  */
 static inline struct iw_statistics *get_wireless_stats(struct net_device *dev)
 {
 	return (dev->get_wireless_stats ?
 		dev->get_wireless_stats(dev) :
 		(struct iw_statistics *) NULL);
 	/* In the future, get_wireless_stats may move from 'struct net_device'
 	 * to 'struct iw_handler_def', to de-bloat struct net_device.
 	 * Definitely worse a thought... */
 }

 /* ---------------------------------------------------------------- */
 /*
  * Call the commit handler in the driver
  * (if exist and if conditions are right)
  *
  * Note : our current commit strategy is currently pretty dumb,
  * but we will be able to improve on that...
  * The goal is to try to agreagate as many changes as possible
  * before doing the commit. Drivers that will define a commit handler
  * are usually those that need a reset after changing parameters, so
  * we want to minimise the number of reset.
  * A cool idea is to use a timer : at each "set" command, we re-set the
  * timer, when the timer eventually fires, we call the driver.
  * Hopefully, more on that later.
  *
  * Also, I'm waiting to see how many people will complain about the
  * netif_running(dev) test. I'm open on that one...
  * Hopefully, the driver will remember to do a commit in "open()" ;-)
  */
 static inline int call_commit_handler(struct net_device *	dev)
 {
 	if((netif_running(dev)) &&
 	   (dev->wireless_handlers->standard[0] != NULL)) {
 		/* Call the commit handler on the driver */
 		return dev->wireless_handlers->standard[0](dev, NULL,
 							   NULL, NULL);
 	} else
 		return 0;		/* Command completed successfully */
 }

 /* ---------------------------------------------------------------- */
 /*
  * Number of private arguments
  */
 static inline int get_priv_size(__u16	args)
 {
 	int	num = args & IW_PRIV_SIZE_MASK;
 	int	type = (args & IW_PRIV_TYPE_MASK) >> 12;

 	return num * priv_type_size[type];
 }


 /******************** /proc/net/wireless SUPPORT ********************/
 /*
  * The /proc/net/wireless file is a human readable user-space interface
  * exporting various wireless specific statistics from the wireless devices.
  * This is the most popular part of the Wireless Extensions ;-)
  *
  * This interface is a pure clone of /proc/net/dev (in net/core/dev.c).
  * The content of the file is basically the content of "struct iw_statistics".
  */

 #ifdef CONFIG_PROC_FS

 /* ---------------------------------------------------------------- */
 /*
  * Print one entry (line) of /proc/net/wireless
  */
 static inline int sprintf_wireless_stats(char *buffer, struct net_device *dev)
 {
 	/* Get stats from the driver */
 	struct iw_statistics *stats;
 	int size;

 	stats = get_wireless_stats(dev);
 	if (stats != (struct iw_statistics *) NULL) {
 		size = sprintf(buffer,
 			       "%6s: %04x  %3d%c  %3d%c  %3d%c  %6d %6d %6d %6d %6d   %6d\n",
 			       dev->name,
 			       stats->status,
 			       stats->qual.qual,
 			       stats->qual.updated & 1 ? '.' : ' ',
 			       stats->qual.level,
 			       stats->qual.updated & 2 ? '.' : ' ',
 			       stats->qual.noise,
 			       stats->qual.updated & 4 ? '.' : ' ',
 			       stats->discard.nwid,
 			       stats->discard.code,
 			       stats->discard.fragment,
 			       stats->discard.retries,
 			       stats->discard.misc,
 			       stats->miss.beacon);
 		stats->qual.updated = 0;
 	}
 	else
 		size = 0;

 	return size;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Print info for /proc/net/wireless (print all entries)
  */
 int dev_get_wireless_info(char * buffer, char **start, off_t offset,
 			  int length)
 {
 	int		len = 0;
 	off_t		begin = 0;
 	off_t		pos = 0;
 	int		size;

 	struct net_device *	dev;

 	size = sprintf(buffer,
 		       "Inter-| sta-|   Quality        |   Discarded packets               | Missed\n"
 		       " face | tus | link level noise |  nwid  crypt   frag  retry   misc | beacon\n"
 			);

 	pos += size;
 	len += size;

 	read_lock(&dev_base_lock);
 	for (dev = dev_base; dev != NULL; dev = dev->next) {
 		size = sprintf_wireless_stats(buffer + len, dev);
 		len += size;
 		pos = begin + len;

 		if (pos < offset) {
 			len = 0;
 			begin = pos;
 		}
 		if (pos > offset + length)
 			break;
 	}
 	read_unlock(&dev_base_lock);

 	*start = buffer + (offset - begin);	/* Start of wanted data */
 	len -= (offset - begin);		/* Start slop */
 	if (len > length)
 		len = length;			/* Ending slop */
 	if (len < 0)
 		len = 0;

 	return len;
 }
 #endif	/* CONFIG_PROC_FS */

 /************************** IOCTL SUPPORT **************************/
 /*
  * The original user space API to configure all those Wireless Extensions
  * is through IOCTLs.
  * In there, we check if we need to call the new driver API (iw_handler)
  * or just call the driver ioctl handler.
  */

 /* ---------------------------------------------------------------- */
 /*
  *	Allow programatic access to /proc/net/wireless even if /proc
  *	doesn't exist... Also more efficient...
  */
 static inline int dev_iwstats(struct net_device *dev, struct ifreq *ifr)
 {
 	/* Get stats from the driver */
 	struct iw_statistics *stats;

 	stats = get_wireless_stats(dev);
 	if (stats != (struct iw_statistics *) NULL) {
 		struct iwreq *	wrq = (struct iwreq *)ifr;

 		/* Copy statistics to the user buffer */
 		if(copy_to_user(wrq->u.data.pointer, stats,
 				sizeof(struct iw_statistics)))
 			return -EFAULT;

 		/* Check if we need to clear the update flag */
 		if(wrq->u.data.flags != 0)
 			stats->qual.updated = 0;
 		return 0;
 	} else
 		return -EOPNOTSUPP;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Export the driver private handler definition
  * They will be picked up by tools like iwpriv...
  */
 static inline int ioctl_export_private(struct net_device *	dev,
 				       struct ifreq *		ifr)
 {
 	struct iwreq *				iwr = (struct iwreq *) ifr;

 	/* Check if the driver has something to export */
 	if((dev->wireless_handlers->num_private_args == 0) ||
 	   (dev->wireless_handlers->private_args == NULL))
 		return -EOPNOTSUPP;

 	/* Check NULL pointer */
 	if(iwr->u.data.pointer == NULL)
 		return -EFAULT;
 #ifdef WE_STRICT_WRITE
 	/* Check if there is enough buffer up there */
 	if(iwr->u.data.length < (SIOCIWLASTPRIV - SIOCIWFIRSTPRIV + 1))
 		return -E2BIG;
 #endif	/* WE_STRICT_WRITE */

 	/* Set the number of available ioctls. */
 	iwr->u.data.length = dev->wireless_handlers->num_private_args;

 	/* Copy structure to the user buffer. */
 	if (copy_to_user(iwr->u.data.pointer,
 			 dev->wireless_handlers->private_args,
 			 sizeof(struct iw_priv_args) * iwr->u.data.length))
 		return -EFAULT;

 	return 0;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Wrapper to call a standard Wireless Extension handler.
  * We do various checks and also take care of moving data between
  * user space and kernel space.
  */
 static inline int ioctl_standard_call(struct net_device *	dev,
 				      struct ifreq *		ifr,
 				      unsigned int		cmd,
 				      iw_handler		handler)
 {
 	struct iwreq *				iwr = (struct iwreq *) ifr;
 	const struct iw_ioctl_description *	descr;
 	struct iw_request_info			info;
 	int					ret = -EINVAL;

 	/* Get the description of the IOCTL */
 	descr = &(standard_ioctl[cmd - SIOCIWFIRST]);

 #ifdef WE_IOCTL_DEBUG
 	printk(KERN_DEBUG "%s : Found standard handler for 0x%04X\n",
 	       ifr->ifr_name, cmd);
 	printk(KERN_DEBUG "Header type : %d, token type : %d, token_size : %d, max_token : %d\n", descr->header_type, descr->token_type, descr->token_size, descr->max_tokens);
 #endif	/* WE_IOCTL_DEBUG */

 	/* Prepare the call */
 	info.cmd = cmd;
 	info.flags = 0;

 	/* Check if we have a pointer to user space data or not */
 	if(descr->header_type != IW_HEADER_TYPE_POINT) {
 		/* No extra arguments. Trivial to handle */
 		ret = handler(dev, &info, &(iwr->u), NULL);
 	} else {
 		char *	extra;
 		int	err;

 		/* Check what user space is giving us */
 		if(IW_IS_SET(cmd)) {
 			/* Check NULL pointer */
 			if((iwr->u.data.pointer == NULL) &&
 			   (iwr->u.data.length != 0))
 				return -EFAULT;
 			/* Check if number of token fits within bounds */
 			if(iwr->u.data.length > descr->max_tokens)
 				return -E2BIG;
 			if(iwr->u.data.length < descr->min_tokens)
 				return -EINVAL;
 		} else {
 			/* Check NULL pointer */
 			if(iwr->u.data.pointer == NULL)
 				return -EFAULT;
 #ifdef WE_STRICT_WRITE
 			/* Check if there is enough buffer up there */
 			if(iwr->u.data.length < descr->max_tokens)
 				return -E2BIG;
 #endif	/* WE_STRICT_WRITE */
 		}

 #ifdef WE_IOCTL_DEBUG
 		printk(KERN_DEBUG "Malloc %d bytes\n",
 		       descr->max_tokens * descr->token_size);
 #endif	/* WE_IOCTL_DEBUG */

 		/* Always allocate for max space. Easier, and won't last
 		 * long... */
 		extra = kmalloc(descr->max_tokens * descr->token_size,
 				GFP_KERNEL);
 		if (extra == NULL) {
 			return -ENOMEM;
 		}

 		/* If it is a SET, get all the extra data in here */
 		if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
 			err = copy_from_user(extra, iwr->u.data.pointer,
 					     iwr->u.data.length *
 					     descr->token_size);
 			if (err) {
 				kfree(extra);
 				return -EFAULT;
 			}
 #ifdef WE_IOCTL_DEBUG
 			printk(KERN_DEBUG "Got %d bytes\n",
 			       iwr->u.data.length * descr->token_size);
 #endif	/* WE_IOCTL_DEBUG */
 		}

 		/* Call the handler */
 		ret = handler(dev, &info, &(iwr->u), extra);

 		/* If we have something to return to the user */
 		if (!ret && IW_IS_GET(cmd)) {
 			err = copy_to_user(iwr->u.data.pointer, extra,
 					   iwr->u.data.length *
 					   descr->token_size);
 			if (err)
 				ret =  -EFAULT;
 #ifdef WE_IOCTL_DEBUG
 			printk(KERN_DEBUG "Wrote %d bytes\n",
 			       iwr->u.data.length * descr->token_size);
 #endif	/* WE_IOCTL_DEBUG */
 		}

 		/* Cleanup - I told you it wasn't that long ;-) */
 		kfree(extra);
 	}

 	/* Call commit handler if needed and defined */
 	if(ret == -EIWCOMMIT)
 		ret = call_commit_handler(dev);

 	/* Here, we will generate the appropriate event if needed */

 	return ret;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Wrapper to call a private Wireless Extension handler.
  * We do various checks and also take care of moving data between
  * user space and kernel space.
  * It's not as nice and slimline as the standard wrapper. The cause
  * is struct iw_priv_args, which was not really designed for the
  * job we are going here.
  *
  * IMPORTANT : This function prevent to set and get data on the same
  * IOCTL and enforce the SET/GET convention. Not doing it would be
  * far too hairy...
  * If you need to set and get data at the same time, please don't use
  * a iw_handler but process it in your ioctl handler (i.e. use the
  * old driver API).
  */
 static inline int ioctl_private_call(struct net_device *	dev,
 				     struct ifreq *		ifr,
 				     unsigned int		cmd,
 				     iw_handler		handler)
 {
 	struct iwreq *			iwr = (struct iwreq *) ifr;
 	struct iw_priv_args *		descr = NULL;
 	struct iw_request_info		info;
 	int				extra_size = 0;
 	int				i;
 	int				ret = -EINVAL;

 	/* Get the description of the IOCTL */
 	for(i = 0; i < dev->wireless_handlers->num_private_args; i++)
 		if(cmd == dev->wireless_handlers->private_args[i].cmd) {
 			descr = &(dev->wireless_handlers->private_args[i]);
 			break;
 		}

 #ifdef WE_IOCTL_DEBUG
 	printk(KERN_DEBUG "%s : Found private handler for 0x%04X\n",
 	       ifr->ifr_name, cmd);
 	if(descr) {
 		printk(KERN_DEBUG "Name %s, set %X, get %X\n",
 		       descr->name, descr->set_args, descr->get_args);
 	}
 #endif	/* WE_IOCTL_DEBUG */

 	/* Compute the size of the set/get arguments */
 	if(descr != NULL) {
 		if(IW_IS_SET(cmd)) {
 			/* Size of set arguments */
 			extra_size = get_priv_size(descr->set_args);

 			/* Does it fits in iwr ? */
 			if((descr->set_args & IW_PRIV_SIZE_FIXED) &&
 			   (extra_size < IFNAMSIZ))
 				extra_size = 0;
 		} else {
 			/* Size of set arguments */
 			extra_size = get_priv_size(descr->get_args);

 			/* Does it fits in iwr ? */
 			if((descr->get_args & IW_PRIV_SIZE_FIXED) &&
 			   (extra_size < IFNAMSIZ))
 				extra_size = 0;
 		}
 	}

 	/* Prepare the call */
 	info.cmd = cmd;
 	info.flags = 0;

 	/* Check if we have a pointer to user space data or not. */
 	if(extra_size == 0) {
 		/* No extra arguments. Trivial to handle */
 		ret = handler(dev, &info, &(iwr->u), (char *) &(iwr->u));
 	} else {
 		char *	extra;
 		int	err;

 		/* Check what user space is giving us */
 		if(IW_IS_SET(cmd)) {
 			/* Check NULL pointer */
 			if((iwr->u.data.pointer == NULL) &&
 			   (iwr->u.data.length != 0))
 				return -EFAULT;

 			/* Does it fits within bounds ? */
 			if(iwr->u.data.length > (descr->set_args &
 						 IW_PRIV_SIZE_MASK))
 				return -E2BIG;
 		} else {
 			/* Check NULL pointer */
 			if(iwr->u.data.pointer == NULL)
 				return -EFAULT;
 		}

 #ifdef WE_IOCTL_DEBUG
 		printk(KERN_DEBUG "Malloc %d bytes\n", extra_size);
 #endif	/* WE_IOCTL_DEBUG */

 		/* Always allocate for max space. Easier, and won't last
 		 * long... */
 		extra = kmalloc(extra_size, GFP_KERNEL);
 		if (extra == NULL) {
 			return -ENOMEM;
 		}

 		/* If it is a SET, get all the extra data in here */
 		if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
 			err = copy_from_user(extra, iwr->u.data.pointer,
 					     extra_size);
 			if (err) {
 				kfree(extra);
 				return -EFAULT;
 			}
 #ifdef WE_IOCTL_DEBUG
 			printk(KERN_DEBUG "Got %d elem\n", iwr->u.data.length);
 #endif	/* WE_IOCTL_DEBUG */
 		}

 		/* Call the handler */
 		ret = handler(dev, &info, &(iwr->u), extra);

 		/* If we have something to return to the user */
 		if (!ret && IW_IS_GET(cmd)) {
 			err = copy_to_user(iwr->u.data.pointer, extra,
 					   extra_size);
 			if (err)
 				ret =  -EFAULT;
 #ifdef WE_IOCTL_DEBUG
 			printk(KERN_DEBUG "Wrote %d elem\n",
 			       iwr->u.data.length);
 #endif	/* WE_IOCTL_DEBUG */
 		}

 		/* Cleanup - I told you it wasn't that long ;-) */
 		kfree(extra);
 	}


 	/* Call commit handler if needed and defined */
 	if(ret == -EIWCOMMIT)
 		ret = call_commit_handler(dev);

 	return ret;
 }

 /* ---------------------------------------------------------------- */
 /*
  * Main IOCTl dispatcher. Called from the main networking code
  * (dev_ioctl() in net/core/dev.c).
  * Check the type of IOCTL and call the appropriate wrapper...
  */
 int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
 {
 	struct net_device *dev;
 	iw_handler	handler;

 	/* Permissions are already checked in dev_ioctl() before calling us.
 	 * The copy_to/from_user() of ifr is also dealt with in there */

 	/* Make sure the device exist */
 	if ((dev = __dev_get_by_name(ifr->ifr_name)) == NULL)
 		return -ENODEV;

 	/* A bunch of special cases, then the generic case...
 	 * Note that 'cmd' is already filtered in dev_ioctl() with
 	 * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
 	switch(cmd)
 	{
 		case SIOCGIWSTATS:
 			/* Get Wireless Stats */
 			return dev_iwstats(dev, ifr);

 		case SIOCGIWPRIV:
 			/* Check if we have some wireless handlers defined */
 			if(dev->wireless_handlers != NULL) {
 				/* We export to user space the definition of
 				 * the private handler ourselves */
 				return ioctl_export_private(dev, ifr);
 			}
 			// ## Fall-through for old API ##
 		default:
 			/* Generic IOCTL */
 			/* Basic check */
 			if (!netif_device_present(dev))
 				return -ENODEV;
 			/* New driver API : try to find the handler */
 			handler = get_handler(dev, cmd);
 			if(handler != NULL) {
 				/* Standard and private are not the same */
 				if(cmd < SIOCIWFIRSTPRIV)
 					return ioctl_standard_call(dev,
 								   ifr,
 								   cmd,
 								   handler);
 				else
 					return ioctl_private_call(dev,
 								  ifr,
 								  cmd,
 								  handler);
 			}
 			/* Old driver API : call driver ioctl handler */
 			if (dev->do_ioctl) {
 				return dev->do_ioctl(dev, ifr, cmd);
 			}
 			return -EOPNOTSUPP;
 	}
 	/* Not reached */
 	return -EINVAL;
 }
	/*
	* This file implement the Wireless Extensions APIs.
	*
	* Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
	* Copyright (c) 1997-2001 Jean Tourrilhes, All Rights Reserved.
	*
	* (As all part of the Linux kernel, this file is GPL)
	*/

	/************************ DOCUMENTATION ************************/
	/*
	* API definition :
	* --------------
	* See <linux/wireless.h> for details of the APIs and the rest.
	*
	* History :
	* -------
	*
	* v1 - 5.12.01 - Jean II
	* o Created this file.
	*
	* v2 - 13.12.01 - Jean II
	* o Move /proc/net/wireless stuff from net/core/dev.c to here
	* o Make Wireless Extension IOCTLs go through here
	* o Added iw_handler handling ;-)
	* o Added standard ioctl description
	* o Initial dumb commit strategy based on orinoco.c
	*/

	/*************************** INCLUDES ***************************/

	#include <asm/uaccess.h> /* copy_to_user() */
	#include <linux/config.h> /* Not needed ??? */
	#include <linux/types.h> /* off_t */
	#include <linux/netdevice.h> /* struct ifreq, dev_get_by_name() */

	#include <linux/wireless.h> /* Pretty obvious */
	#include <net/iw_handler.h> /* New driver API */

	/************************** CONSTANTS **************************/

	/* This will be turned on later on... */
	#undef WE_STRICT_WRITE /* Check write buffer size */

	/* Debuging stuff */
	#undef WE_IOCTL_DEBUG /* Debug IOCTL API */

	/*********************** GLOBAL VARIABLES ***********************/
	/*
	* You should not use global variables, because or re-entrancy.
	* On our case, it's only const, so it's OK...
	*/
	static const struct iw_ioctl_description standard_ioctl[] = {
	/* SIOCSIWCOMMIT (internal) */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCGIWNAME */
	{ IW_HEADER_TYPE_CHAR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWNWID */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
	/* SIOCGIWNWID */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWFREQ */
	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
	/* SIOCGIWFREQ */
	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWMODE */
	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
	/* SIOCGIWMODE */
	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWSENS */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWSENS */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWRANGE */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCGIWRANGE */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, sizeof(struct iw_range), IW_DESCR_FLAG_DUMP},
	/* SIOCSIWPRIV */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCGIWPRIV (handled directly by us) */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCSIWSTATS */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCGIWSTATS (handled directly by us) */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWSPY */
	{ IW_HEADER_TYPE_POINT, 0, sizeof(struct sockaddr), 0, IW_MAX_SPY, 0},
	/* SIOCGIWSPY */
	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_SPY, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCSIWAP */
	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, 0},
	/* SIOCGIWAP */
	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCGIWAPLIST */
	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_AP, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCSIWESSID */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_EVENT},
	/* SIOCGIWESSID */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_DUMP},
	/* SIOCSIWNICKN */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
	/* SIOCGIWNICKN */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* -- hole -- */
	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
	/* SIOCSIWRATE */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWRATE */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWRTS */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWRTS */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWFRAG */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWFRAG */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWTXPOW */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWTXPOW */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWRETRY */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWRETRY */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCSIWENCODE */
	{ IW_HEADER_TYPE_POINT, 4, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_EVENT \| IW_DESCR_FLAG_RESTRICT},
	/* SIOCGIWENCODE */
	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_DUMP \| IW_DESCR_FLAG_RESTRICT},
	/* SIOCSIWPOWER */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	/* SIOCGIWPOWER */
	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
	};

	/* Size (in bytes) of the various private data types */
	char priv_type_size[] = { 0, 1, 1, 0, 4, 4, 0, 0 };

	/********************** COMMON SUBROUTINES **********************/
	/*
	* Stuff that may be used in various place or doesn't fit in one
	* of the section below.
	*/

	/* ---------------------------------------------------------------- */
	/*
	* Return the driver handler associated with a specific Wireless Extension.
	* Called from various place, so make sure it remains efficient.
	*/
	static inline iw_handler get_handler(struct net_device *dev,
	unsigned int cmd)
	{
	unsigned int index; /* MUST be unsigned */

	/* Check if we have some wireless handlers defined */
	if(dev->wireless_handlers == NULL)
	return NULL;

	/* Try as a standard command */
	index = cmd - SIOCIWFIRST;
	if(index < dev->wireless_handlers->num_standard)
	return dev->wireless_handlers->standard[index];

	/* Try as a private command */
	index = cmd - SIOCIWFIRSTPRIV;
	if(index < dev->wireless_handlers->num_private)
	return dev->wireless_handlers->private[index];

	/* Not found */
	return NULL;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Get statistics out of the driver
	*/
	static inline struct iw_statistics get_wireless_stats(struct net_device dev)
	{
	return (dev->get_wireless_stats ?
	dev->get_wireless_stats(dev) :
	(struct iw_statistics *) NULL);
	/* In the future, get_wireless_stats may move from 'struct net_device'
	* to 'struct iw_handler_def', to de-bloat struct net_device.
	* Definitely worse a thought... */
	}

	/* ---------------------------------------------------------------- */
	/*
	* Call the commit handler in the driver
	* (if exist and if conditions are right)
	*
	* Note : our current commit strategy is currently pretty dumb,
	* but we will be able to improve on that...
	* The goal is to try to agreagate as many changes as possible
	* before doing the commit. Drivers that will define a commit handler
	* are usually those that need a reset after changing parameters, so
	* we want to minimise the number of reset.
	* A cool idea is to use a timer : at each "set" command, we re-set the
	* timer, when the timer eventually fires, we call the driver.
	* Hopefully, more on that later.
	*
	* Also, I'm waiting to see how many people will complain about the
	* netif_running(dev) test. I'm open on that one...
	* Hopefully, the driver will remember to do a commit in "open()" ;-)
	*/
	static inline int call_commit_handler(struct net_device * dev)
	{
	if((netif_running(dev)) &&
	(dev->wireless_handlers->standard[0] != NULL)) {
	/* Call the commit handler on the driver */
	return dev->wireless_handlers->standard[0](dev, NULL,
	NULL, NULL);
	} else
	return 0; /* Command completed successfully */
	}

	/* ---------------------------------------------------------------- */
	/*
	* Number of private arguments
	*/
	static inline int get_priv_size(__u16 args)
	{
	int num = args & IW_PRIV_SIZE_MASK;
	int type = (args & IW_PRIV_TYPE_MASK) >> 12;

	return num * priv_type_size[type];
	}


	/****************** /proc/net/wireless SUPPORT ******************/
	/*
	* The /proc/net/wireless file is a human readable user-space interface
	* exporting various wireless specific statistics from the wireless devices.
	* This is the most popular part of the Wireless Extensions ;-)
	*
	* This interface is a pure clone of /proc/net/dev (in net/core/dev.c).
	* The content of the file is basically the content of "struct iw_statistics".
	*/

	#ifdef CONFIG_PROC_FS

	/* ---------------------------------------------------------------- */
	/*
	* Print one entry (line) of /proc/net/wireless
	*/
	static inline int sprintf_wireless_stats(char buffer, struct net_device dev)
	{
	/* Get stats from the driver */
	struct iw_statistics *stats;
	int size;

	stats = get_wireless_stats(dev);
	if (stats != (struct iw_statistics *) NULL) {
	size = sprintf(buffer,
	"%6s: %04x %3d%c %3d%c %3d%c %6d %6d %6d %6d %6d %6d\n",
	dev->name,
	stats->status,
	stats->qual.qual,
	stats->qual.updated & 1 ? '.' : ' ',
	stats->qual.level,
	stats->qual.updated & 2 ? '.' : ' ',
	stats->qual.noise,
	stats->qual.updated & 4 ? '.' : ' ',
	stats->discard.nwid,
	stats->discard.code,
	stats->discard.fragment,
	stats->discard.retries,
	stats->discard.misc,
	stats->miss.beacon);
	stats->qual.updated = 0;
	}
	else
	size = 0;

	return size;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Print info for /proc/net/wireless (print all entries)
	*/
	int dev_get_wireless_info(char * buffer, char **start, off_t offset,
	int length)
	{
	int len = 0;
	off_t begin = 0;
	off_t pos = 0;
	int size;

	struct net_device * dev;

	size = sprintf(buffer,
	"Inter-\| sta-\| Quality \| Discarded packets \| Missed\n"
	" face \| tus \| link level noise \| nwid crypt frag retry misc \| beacon\n"
	);

	pos += size;
	len += size;

	read_lock(&dev_base_lock);
	for (dev = dev_base; dev != NULL; dev = dev->next) {
	size = sprintf_wireless_stats(buffer + len, dev);
	len += size;
	pos = begin + len;

	if (pos < offset) {
	len = 0;
	begin = pos;
	}
	if (pos > offset + length)
	break;
	}
	read_unlock(&dev_base_lock);

	start = buffer + (offset - begin); / Start of wanted data */
	len -= (offset - begin); /* Start slop */
	if (len > length)
	len = length; /* Ending slop */
	if (len < 0)
	len = 0;

	return len;
	}
	#endif /* CONFIG_PROC_FS */

	/************************ IOCTL SUPPORT ************************/
	/*
	* The original user space API to configure all those Wireless Extensions
	* is through IOCTLs.
	* In there, we check if we need to call the new driver API (iw_handler)
	* or just call the driver ioctl handler.
	*/

	/* ---------------------------------------------------------------- */
	/*
	* Allow programatic access to /proc/net/wireless even if /proc
	* doesn't exist... Also more efficient...
	*/
	static inline int dev_iwstats(struct net_device dev, struct ifreq ifr)
	{
	/* Get stats from the driver */
	struct iw_statistics *stats;

	stats = get_wireless_stats(dev);
	if (stats != (struct iw_statistics *) NULL) {
	struct iwreq * wrq = (struct iwreq *)ifr;

	/* Copy statistics to the user buffer */
	if(copy_to_user(wrq->u.data.pointer, stats,
	sizeof(struct iw_statistics)))
	return -EFAULT;

	/* Check if we need to clear the update flag */
	if(wrq->u.data.flags != 0)
	stats->qual.updated = 0;
	return 0;
	} else
	return -EOPNOTSUPP;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Export the driver private handler definition
	* They will be picked up by tools like iwpriv...
	*/
	static inline int ioctl_export_private(struct net_device * dev,
	struct ifreq * ifr)
	{
	struct iwreq * iwr = (struct iwreq *) ifr;

	/* Check if the driver has something to export */
	if((dev->wireless_handlers->num_private_args == 0) \|\|
	(dev->wireless_handlers->private_args == NULL))
	return -EOPNOTSUPP;

	/* Check NULL pointer */
	if(iwr->u.data.pointer == NULL)
	return -EFAULT;
	#ifdef WE_STRICT_WRITE
	/* Check if there is enough buffer up there */
	if(iwr->u.data.length < (SIOCIWLASTPRIV - SIOCIWFIRSTPRIV + 1))
	return -E2BIG;
	#endif /* WE_STRICT_WRITE */

	/* Set the number of available ioctls. */
	iwr->u.data.length = dev->wireless_handlers->num_private_args;

	/* Copy structure to the user buffer. */
	if (copy_to_user(iwr->u.data.pointer,
	dev->wireless_handlers->private_args,
	sizeof(struct iw_priv_args) * iwr->u.data.length))
	return -EFAULT;

	return 0;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Wrapper to call a standard Wireless Extension handler.
	* We do various checks and also take care of moving data between
	* user space and kernel space.
	*/
	static inline int ioctl_standard_call(struct net_device * dev,
	struct ifreq * ifr,
	unsigned int cmd,
	iw_handler handler)
	{
	struct iwreq * iwr = (struct iwreq *) ifr;
	const struct iw_ioctl_description * descr;
	struct iw_request_info info;
	int ret = -EINVAL;

	/* Get the description of the IOCTL */
	descr = &(standard_ioctl[cmd - SIOCIWFIRST]);

	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "%s : Found standard handler for 0x%04X\n",
	ifr->ifr_name, cmd);
	printk(KERN_DEBUG "Header type : %d, token type : %d, token_size : %d, max_token : %d\n", descr->header_type, descr->token_type, descr->token_size, descr->max_tokens);
	#endif /* WE_IOCTL_DEBUG */

	/* Prepare the call */
	info.cmd = cmd;
	info.flags = 0;

	/* Check if we have a pointer to user space data or not */
	if(descr->header_type != IW_HEADER_TYPE_POINT) {
	/* No extra arguments. Trivial to handle */
	ret = handler(dev, &info, &(iwr->u), NULL);
	} else {
	char * extra;
	int err;

	/* Check what user space is giving us */
	if(IW_IS_SET(cmd)) {
	/* Check NULL pointer */
	if((iwr->u.data.pointer == NULL) &&
	(iwr->u.data.length != 0))
	return -EFAULT;
	/* Check if number of token fits within bounds */
	if(iwr->u.data.length > descr->max_tokens)
	return -E2BIG;
	if(iwr->u.data.length < descr->min_tokens)
	return -EINVAL;
	} else {
	/* Check NULL pointer */
	if(iwr->u.data.pointer == NULL)
	return -EFAULT;
	#ifdef WE_STRICT_WRITE
	/* Check if there is enough buffer up there */
	if(iwr->u.data.length < descr->max_tokens)
	return -E2BIG;
	#endif /* WE_STRICT_WRITE */
	}

	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Malloc %d bytes\n",
	descr->max_tokens * descr->token_size);
	#endif /* WE_IOCTL_DEBUG */

	/* Always allocate for max space. Easier, and won't last
	* long... */
	extra = kmalloc(descr->max_tokens * descr->token_size,
	GFP_KERNEL);
	if (extra == NULL) {
	return -ENOMEM;
	}

	/* If it is a SET, get all the extra data in here */
	if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
	err = copy_from_user(extra, iwr->u.data.pointer,
	iwr->u.data.length *
	descr->token_size);
	if (err) {
	kfree(extra);
	return -EFAULT;
	}
	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Got %d bytes\n",
	iwr->u.data.length * descr->token_size);
	#endif /* WE_IOCTL_DEBUG */
	}

	/* Call the handler */
	ret = handler(dev, &info, &(iwr->u), extra);

	/* If we have something to return to the user */
	if (!ret && IW_IS_GET(cmd)) {
	err = copy_to_user(iwr->u.data.pointer, extra,
	iwr->u.data.length *
	descr->token_size);
	if (err)
	ret = -EFAULT;
	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Wrote %d bytes\n",
	iwr->u.data.length * descr->token_size);
	#endif /* WE_IOCTL_DEBUG */
	}

	/* Cleanup - I told you it wasn't that long ;-) */
	kfree(extra);
	}

	/* Call commit handler if needed and defined */
	if(ret == -EIWCOMMIT)
	ret = call_commit_handler(dev);

	/* Here, we will generate the appropriate event if needed */

	return ret;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Wrapper to call a private Wireless Extension handler.
	* We do various checks and also take care of moving data between
	* user space and kernel space.
	* It's not as nice and slimline as the standard wrapper. The cause
	* is struct iw_priv_args, which was not really designed for the
	* job we are going here.
	*
	* IMPORTANT : This function prevent to set and get data on the same
	* IOCTL and enforce the SET/GET convention. Not doing it would be
	* far too hairy...
	* If you need to set and get data at the same time, please don't use
	* a iw_handler but process it in your ioctl handler (i.e. use the
	* old driver API).
	*/
	static inline int ioctl_private_call(struct net_device * dev,
	struct ifreq * ifr,
	unsigned int cmd,
	iw_handler handler)
	{
	struct iwreq * iwr = (struct iwreq *) ifr;
	struct iw_priv_args * descr = NULL;
	struct iw_request_info info;
	int extra_size = 0;
	int i;
	int ret = -EINVAL;

	/* Get the description of the IOCTL */
	for(i = 0; i < dev->wireless_handlers->num_private_args; i++)
	if(cmd == dev->wireless_handlers->private_args[i].cmd) {
	descr = &(dev->wireless_handlers->private_args[i]);
	break;
	}

	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "%s : Found private handler for 0x%04X\n",
	ifr->ifr_name, cmd);
	if(descr) {
	printk(KERN_DEBUG "Name %s, set %X, get %X\n",
	descr->name, descr->set_args, descr->get_args);
	}
	#endif /* WE_IOCTL_DEBUG */

	/* Compute the size of the set/get arguments */
	if(descr != NULL) {
	if(IW_IS_SET(cmd)) {
	/* Size of set arguments */
	extra_size = get_priv_size(descr->set_args);

	/* Does it fits in iwr ? */
	if((descr->set_args & IW_PRIV_SIZE_FIXED) &&
	(extra_size < IFNAMSIZ))
	extra_size = 0;
	} else {
	/* Size of set arguments */
	extra_size = get_priv_size(descr->get_args);

	/* Does it fits in iwr ? */
	if((descr->get_args & IW_PRIV_SIZE_FIXED) &&
	(extra_size < IFNAMSIZ))
	extra_size = 0;
	}
	}

	/* Prepare the call */
	info.cmd = cmd;
	info.flags = 0;

	/* Check if we have a pointer to user space data or not. */
	if(extra_size == 0) {
	/* No extra arguments. Trivial to handle */
	ret = handler(dev, &info, &(iwr->u), (char *) &(iwr->u));
	} else {
	char * extra;
	int err;

	/* Check what user space is giving us */
	if(IW_IS_SET(cmd)) {
	/* Check NULL pointer */
	if((iwr->u.data.pointer == NULL) &&
	(iwr->u.data.length != 0))
	return -EFAULT;

	/* Does it fits within bounds ? */
	if(iwr->u.data.length > (descr->set_args &
	IW_PRIV_SIZE_MASK))
	return -E2BIG;
	} else {
	/* Check NULL pointer */
	if(iwr->u.data.pointer == NULL)
	return -EFAULT;
	}

	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Malloc %d bytes\n", extra_size);
	#endif /* WE_IOCTL_DEBUG */

	/* Always allocate for max space. Easier, and won't last
	* long... */
	extra = kmalloc(extra_size, GFP_KERNEL);
	if (extra == NULL) {
	return -ENOMEM;
	}

	/* If it is a SET, get all the extra data in here */
	if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
	err = copy_from_user(extra, iwr->u.data.pointer,
	extra_size);
	if (err) {
	kfree(extra);
	return -EFAULT;
	}
	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Got %d elem\n", iwr->u.data.length);
	#endif /* WE_IOCTL_DEBUG */
	}

	/* Call the handler */
	ret = handler(dev, &info, &(iwr->u), extra);

	/* If we have something to return to the user */
	if (!ret && IW_IS_GET(cmd)) {
	err = copy_to_user(iwr->u.data.pointer, extra,
	extra_size);
	if (err)
	ret = -EFAULT;
	#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "Wrote %d elem\n",
	iwr->u.data.length);
	#endif /* WE_IOCTL_DEBUG */
	}

	/* Cleanup - I told you it wasn't that long ;-) */
	kfree(extra);
	}


	/* Call commit handler if needed and defined */
	if(ret == -EIWCOMMIT)
	ret = call_commit_handler(dev);

	return ret;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Main IOCTl dispatcher. Called from the main networking code
	* (dev_ioctl() in net/core/dev.c).
	* Check the type of IOCTL and call the appropriate wrapper...
	*/
	int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
	{
	struct net_device *dev;
	iw_handler handler;

	/* Permissions are already checked in dev_ioctl() before calling us.
	* The copy_to/from_user() of ifr is also dealt with in there */

	/* Make sure the device exist */
	if ((dev = __dev_get_by_name(ifr->ifr_name)) == NULL)
	return -ENODEV;

	/* A bunch of special cases, then the generic case...
	* Note that 'cmd' is already filtered in dev_ioctl() with
	* (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
	switch(cmd)
	{
	case SIOCGIWSTATS:
	/* Get Wireless Stats */
	return dev_iwstats(dev, ifr);

	case SIOCGIWPRIV:
	/* Check if we have some wireless handlers defined */
	if(dev->wireless_handlers != NULL) {
	/* We export to user space the definition of
	* the private handler ourselves */
	return ioctl_export_private(dev, ifr);
	}
	// ## Fall-through for old API ##
	default:
	/* Generic IOCTL */
	/* Basic check */
	if (!netif_device_present(dev))
	return -ENODEV;
	/* New driver API : try to find the handler */
	handler = get_handler(dev, cmd);
	if(handler != NULL) {
	/* Standard and private are not the same */
	if(cmd < SIOCIWFIRSTPRIV)
	return ioctl_standard_call(dev,
	ifr,
	cmd,
	handler);
	else
	return ioctl_private_call(dev,
	ifr,
	cmd,
	handler);
	}
	/* Old driver API : call driver ioctl handler */
	if (dev->do_ioctl) {
	return dev->do_ioctl(dev, ifr, cmd);
	}
	return -EOPNOTSUPP;
	}
	/* Not reached */
	return -EINVAL;
	}