p80211req.c

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/* src/p80211/p80211req.c
*
* Request/Indication/MacMgmt interface handling functions
*
* Copyright (C) 1999 AbsoluteValue Systems, Inc.  All Rights Reserved.
* --------------------------------------------------------------------
*
* linux-wlan
*
*   The contents of this file are subject to the Mozilla Public
*   License Version 1.1 (the "License"); you may not use this file
*   except in compliance with the License. You may obtain a copy of
*   the License at http://www.mozilla.org/MPL/
*
*   Software distributed under the License is distributed on an "AS
*   IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
*   implied. See the License for the specific language governing
*   rights and limitations under the License.
*
*   Alternatively, the contents of this file may be used under the
*   terms of the GNU Public License version 2 (the "GPL"), in which
*   case the provisions of the GPL are applicable instead of the
*   above.  If you wish to allow the use of your version of this file
*   only under the terms of the GPL and not to allow others to use
*   your version of this file under the MPL, indicate your decision
*   by deleting the provisions above and replace them with the notice
*   and other provisions required by the GPL.  If you do not delete
*   the provisions above, a recipient may use your version of this
*   file under either the MPL or the GPL.
*
* --------------------------------------------------------------------
*
* Inquiries regarding the linux-wlan Open Source project can be
* made directly to:
*
* AbsoluteValue Systems Inc.
* [e-mail]
* http://www.linux-wlan.com
*
* --------------------------------------------------------------------
*
* Portions of the development of this software were funded by 
* Intersil Corporation as part of PRISM(R) chipset product development.
*
* --------------------------------------------------------------------
*
* This file contains the functions, types, and macros to support the
* MLME request interface that's implemented via the device ioctls.
* 
* --------------------------------------------------------------------
*/

/*================================================================*/
/* System Includes */

#define __NO_VERSION__		/* prevent the static definition */

#include <linux/config.h>
#include <linux/version.h>
#include <wlan/wlan_compat.h>

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <net/sock.h>
#include <linux/netlink.h>

/*================================================================*/
/* Project Includes */

#include <wlan/version.h>
#include <wlan/p80211types.h>
#include <wlan/p80211hdr.h>
#include <wlan/p80211mgmt.h>
#include <wlan/p80211conv.h>
#include <wlan/p80211msg.h>
#include <wlan/p80211netdev.h>
#include <wlan/p80211ioctl.h>
#include <wlan/p80211metadef.h>

/*================================================================*/
/* Local Constants */

/* Maximum amount of time we'll wait for a request to complete */
#define P80211REQ_MAXTIME	3*HZ	/* 3 seconds */

/*================================================================*/
/* Local Macros */

/*================================================================*/
/* Local Types */

typedef void (*timerfunc_t)(unsigned long);


/*================================================================*/
/* Local Static Definitions */

/* Netlink interface(s) */
static struct sock	*nl_indicate = NULL;

/*================================================================*/
/* Local Function Declarations */

static void p80211req_timerfunc(wlandevice_t *wlandev);
static void p80211req_handlemsg( wlandevice_t *wlandev, p80211msg_t *msg);
#ifdef CONFIG_NETLINK
static void p80211ind_rx(struct sock *sk, int len);
#endif

/*================================================================*/
/* Function Definitions */


/*----------------------------------------------------------------
* p80211req_dorequest
*
* Handles an MLME reqest/confirm message.
* 
* Arguments:
*	wlandev		WLAN device struct
*	msgbuf		Buffer containing a request message
*
* Returns: 
*	0 on success, an errno otherwise
*	
* Call context:
*	Potentially blocks the caller, so it's a good idea to 
*	not call this function from an interrupt context.
----------------------------------------------------------------*/
int p80211req_dorequest( wlandevice_t *wlandev, UINT8 *msgbuf)
{
	int		result = 0;
	int		retval;
	p80211msg_t	*msg = (p80211msg_t*)msgbuf;

	DBFENTER;

	/* Check to make sure the MSD is running */
	if ( 
	!((wlandev->msdstate == WLAN_MSD_HWPRESENT &&
	msg->msgcode == DIDmsg_lnxreq_ifstate) ||
	wlandev->msdstate == WLAN_MSD_RUNNING || 
	wlandev->msdstate == WLAN_MSD_FWLOAD) ) {
		return -ENODEV;
	}

	/* Check for busy status */
	if ( test_and_set_bit(1, &(wlandev->request_pending))) {
		return -EBUSY;
	}

	wlandev->curr_msg = msg;

	/* Allow p80211 to look at msg and handle if desired. */
	/* So far, all p80211 msgs are immediate, no waitq/timer necessary */
	/* This may change. */
	p80211req_handlemsg(wlandev, msg);

	/* Pass it down to wlandev via wlandev->mlmerequest */
	if ( wlandev->mlmerequest != NULL ) {
		retval = (*(wlandev->mlmerequest))(wlandev, msg);

		if (retval < 0) {
			/* wlandev is still chewing on it, time to block */
			/* set up wait_q and timeout */
			init_timer(&wlandev->reqtimer);
			wlandev->reqtimer.data = (unsigned long)wlandev;
			wlandev->reqtimer.function = 
				(timerfunc_t)p80211req_timerfunc;
			wlandev->reqtimer.expires = jiffies + P80211REQ_MAXTIME;
			add_timer(&wlandev->reqtimer);

			/* Now, do an interruptible_sleep, */
			/* we'll be awakened by: a signal to the process, */
			/* cmdtimerfunc (timeout), or p80211req_confirm */
			interruptible_sleep_on(&(wlandev->reqwq));

			/* If sleep return is via signal */
			if ( signal_pending(current) ) {
				WLAN_LOG_DEBUG0(2,"req unblocked via signal\n");
				/* stop request, clean up */
				del_timer(&wlandev->reqtimer);
				result = -EINTR;
			} else {
				/* If timeout */
				if ( wlandev->reqtimer.expires == 0 )
				{
					WLAN_LOG_DEBUG0(2,
						"req unblocked via timeout\n");
					/* stop request, clean up request */
					result = -ETIME;
				} else {
					/* Success, clean up timer */
					del_timer(&wlandev->reqtimer);
					wlandev->reqtimer.expires=0;
					result = 0;
				}
			}
		} else {
			result = -retval;  /* retval shld be a positive errno */
		}
	}

	wlandev->curr_msg = NULL;
	clear_bit( 1, &(wlandev->request_pending));
	DBFEXIT;
	return result;	/* if result==0, msg->status still may contain an err */
}


/*----------------------------------------------------------------
* p80211req_timerfunc
*
* Timer function for request timeouts.
* 
* Arguments:
*	wlandev		WLAN device struct
*
* Returns: 
*	nothing
*	
* Call context:
*	Timer interrupt
----------------------------------------------------------------*/
void p80211req_timerfunc(wlandevice_t *wlandev)
{
	wlandev->reqtimer.expires = 0;
	if (wlandev->request_pending != 0) {
		wake_up_interruptible(&(wlandev->reqwq));
	}
}


/*----------------------------------------------------------------
* p80211req_handlemsg
*
* p80211 message handler.  Primarily looks for messages that
* belong to p80211 and then dispatches the appropriate response.
* TODO: we don't do anything yet.  Once the linuxMIB is better
*	defined we'll need a get/set handler.  
* 
* Arguments:
*	wlandev		WLAN device struct
*	msg		message structure
*
* Returns: 
*	nothing (any results are set in the status field of the msg)
*	
* Call context:
*	Process thread
----------------------------------------------------------------*/
void p80211req_handlemsg( wlandevice_t *wlandev, p80211msg_t *msg)
{
	return;
}


/*----------------------------------------------------------------
* p80211req_confirm
*
* Called by the MSD when an asynch request is finished.  Our
* primary job here is to unblock the _dorequest function above.
* 
* Arguments:
*	wlandev		WLAN device struct
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void	p80211req_confirm(wlandevice_t *wlandev)
{
	DBFENTER;

	if ( wlandev->request_pending != 0 ){
		wake_up_interruptible(&(wlandev->reqwq));
	}

	DBFEXIT;
	return;
}


#ifdef CONFIG_NETLINK
/*----------------------------------------------------------------
* p80211indicate_init
*
* Called during the p80211 startup to set up the netlink interfaces
* for sniffing and indication messages.
* 
* Arguments:
*	none
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void p80211indicate_init(void)
{
	DBFENTER;
	nl_indicate = 
		netlink_kernel_create( P80211_NL_SOCK_IND, &p80211ind_rx);
	if ( nl_indicate == NULL ) {
		WLAN_LOG_DEBUG0(2,"Failed to create indicate netlink i/f.\n");
	}
	DBFEXIT;
	return;
}


/*----------------------------------------------------------------
* p80211indicate_shutdown
*
* Called during the p80211 unload to get rid of our netlink 
* interface.
* 
* Arguments:
*	none
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void p80211indicate_shutdown(void)
{
	struct sock	*nl;
	DBFENTER;
	nl = nl_indicate;
	nl_indicate = NULL;
	if ( nl != NULL && nl->socket != NULL) {
		sock_release(nl->socket);
	}
	DBFEXIT;
	return;
}


/*----------------------------------------------------------------
* p80211ind_rx
*
* Called by netlink when a message comes down.  We currently don't
* support message from userland via netlink, so this is a empty
* function.
* 
* Arguments:
*	sk		netlink sock
*	len		msg len
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void p80211ind_rx(struct sock *sk, int len)
{
	return;
}


/*----------------------------------------------------------------
* p80211ind_mlme
*
* Called by the MSD to deliver an mlme type indication message.
* 
* Arguments:
*	wlandev		WLAN device struct
*	skb		skb containing message to deliver
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void p80211ind_mlme( wlandevice_t *wlandev, struct sk_buff *skb)
{
	DBFENTER;
	if ( nl_indicate != NULL ) {

/* TODO: Look at queuing mlme indications when requests are pending. */

		netlink_broadcast(nl_indicate, 
			skb, 0, P80211_NL_MCAST_GRP_MLME, GFP_ATOMIC);
	} else {
		WLAN_LOG_DEBUG0(2,"Can't send indicate msg, no netlink i/f\n");
	}
	DBFEXIT;
	return;
}

/*----------------------------------------------------------------
* p80211ind_distribution
*
* Called by the MSD to deliver a distribution system type 
* indication message.
* 
* Arguments:
*	wlandev		WLAN device struct
*	skb		skb containing message to deliver
*
* Returns: 
*	nothing
*	
* Call context:
*	Any
----------------------------------------------------------------*/
void p80211ind_distribution( wlandevice_t *wlandev, struct sk_buff *skb)
{
	DBFENTER;
	if ( nl_indicate != NULL ) {
/*
		skb = alloc_skb(len, GFP_ATOMIC);
		skb_put(skb, len);
		memcpy(skb->data, msg, len);
*/
		netlink_broadcast(nl_indicate, 
			skb, 0, P80211_NL_MCAST_GRP_DIST, GFP_ATOMIC);
	} else {
		WLAN_LOG_DEBUG0(2,"Can't send indicate msg, no netlink i/f\n");
	}
	DBFEXIT;
	return;
}
#endif /* CONFIG_NETLINK */