xref: /system/wlan/ti/wilink_6_1/stad/src/Sta_Management/siteHash.c

/*
 * siteHash.c
 *
 * Copyright(c) 1998 - 2009 Texas Instruments. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Texas Instruments nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** \file siteHash.c
 *  \brief Site Hash implementation
 *
 *  \see siteHash.h
 */

/****************************************************************************/
/*																			*/
/*		MODULE:	siteHash.c													*/
/*    PURPOSE:	Site Hash implementation 									*/
/*																			*/
/***************************************************************************/

#define __FILE_ID__  FILE_ID_84
#include "tidef.h"
#include "report.h"
#include "osApi.h"
#include "siteMgrApi.h"
#include "siteHash.h"
#include "smeApi.h"


/****************************************************************************************************************

	This file implements the site hash mechanism. This mechanism is used for faster access to the sites information.
	It is compound of the following:
		1.	hash function	-	which maps the 4 last bits of the BSSID to an entry in the hash table.
		2.	hash table		-	each entry in the table points to a linked list of site entries
		3.	site table		-	each entry holds a site information

	In order to find a site in the site table, we operate the hash function on the site's BSSID.
	We receive a hash entry. We go over the linked list pointed by this hash entry until we find the site entry.
*****************************************************************************************************************/

#define WLAN_NUM_OF_MISSED_SACNS_BEFORE_AGING 2


/********************************************/
/*		Functions Implementations			*/
/********************************************/
/************************************************************************
 *                        siteMgr_resetSiteTable						*
 ************************************************************************
DESCRIPTION: reset the following things:
				-	Mgmt parameters structure
				-	Site table
				-	Hash table
				-	Primary site pointer
				-	Number of sites

INPUT:      hSiteMgr				-	Handle to site mgr


OUTPUT:

RETURN:     TI_OK

************************************************************************/
TI_STATUS siteMgr_resetSiteTable(TI_HANDLE	hSiteMgr, siteTablesParams_t	*pSiteTableParams)
{
	int i;
	siteMgr_t		*pSiteMgr = (siteMgr_t *)hSiteMgr;

	os_memoryZero(pSiteMgr->hOs, &pSiteTableParams->siteTable[0], sizeof(siteEntry_t)*pSiteTableParams->maxNumOfSites);

	for (i = 0; i < pSiteTableParams->maxNumOfSites; i++)
	{
		pSiteTableParams->siteTable[i].index = i;
		pSiteTableParams->siteTable[i].siteType = SITE_NULL;
        pSiteTableParams->siteTable[i].beaconRecv = TI_FALSE;
        pSiteTableParams->siteTable[i].dtimPeriod = 1;
	}

	pSiteTableParams->numOfSites = 0;

	pSiteMgr->pSitesMgmtParams->pPrimarySite = NULL;

	return TI_OK;
}

/************************************************************************
 *                        findSiteEntry									*
 ************************************************************************
DESCRIPTION: Perform the following things:
			-	Compute the site's hash entry based on the site BSSID and hash function
			-	Look fotr the site entry in the linked list pointed by the hash entry
			-	If the site is found in the site table, returns a pointer to the site entry
			-	If the site is not found, return NULL.

INPUT:      pSiteMgr	-	Handle to site mgr
			mac			-	The site BSSID


OUTPUT:

RETURN:     Pointer to the site entry if site found, NULL otherwise

************************************************************************/
siteEntry_t	*findSiteEntry(siteMgr_t		*pSiteMgr,
				           TMacAddr 		*mac)
{
    siteTablesParams_t      *pCurrentSiteTable = pSiteMgr->pSitesMgmtParams->pCurrentSiteTable;
	siteEntry_t             *pSiteEntry;
    TI_UINT8                 tableIndex=2, i;


    do
	{
        tableIndex--;
		for (i = 0; i < pCurrentSiteTable->maxNumOfSites; i++)
	    {
			pSiteEntry = &(pCurrentSiteTable->siteTable[i]);

	    	if (MAC_EQUAL (pSiteEntry->bssid, *mac))
	    	{
TRACE6(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "FIND success, bssid: %X-%X-%X-%X-%X-%X\n\n", (*mac)[0], (*mac)[1], (*mac)[2], (*mac)[3], (*mac)[4], (*mac)[5]);
	    		return pSiteEntry;
	    	}

	    }
	   if ((pSiteMgr->pDesiredParams->siteMgrDesiredDot11Mode == DOT11_DUAL_MODE) && (tableIndex==1))
	   {   /* change site table */
	       if (pCurrentSiteTable == &pSiteMgr->pSitesMgmtParams->dot11BG_sitesTables)
              {
                  pCurrentSiteTable = (siteTablesParams_t *)&pSiteMgr->pSitesMgmtParams->dot11A_sitesTables;
              }
	       else
              {
                  pCurrentSiteTable = &pSiteMgr->pSitesMgmtParams->dot11BG_sitesTables;
              }
	   }

    } while (tableIndex>0);



TRACE6(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "FIND failure, bssid: %X-%X-%X-%X-%X-%X\n\n", (*mac)[0], (*mac)[1], (*mac)[2], (*mac)[3], (*mac)[4], (*mac)[5]);


	return NULL;
}

/************************************************************************
 *                        findAndInsertSiteEntry									*
 ************************************************************************
DESCRIPTION: Perform the following things:
			-	Compute the site's hash entry based on the site BSSID and hash function
			-	Look for the site entry in the linked list pointed by the hash entry
			-	If the site is found in the site table, returns a pointer to the site entry
			-	If the site is not found in the site table, tries to add the site
				-	If succeeds, returns a pointer to the site entry
				-	Otherwise, returns NULL

INPUT:      pSiteMgr	-	Handle to site mgr
			mac			-	The site BSSID
            band        -   The site band


OUTPUT:

RETURN:     Pointer to the site entry if site found/inserted, NULL otherwise

************************************************************************/
siteEntry_t	*findAndInsertSiteEntry(siteMgr_t		*pSiteMgr,
									TMacAddr    	*mac,
                                    ERadioBand      band)
{
	TI_UINT8             i, emptySiteIndex=0, nextSite2Remove=0;
	siteEntry_t         *pSiteEntry, *pPrimarySite=pSiteMgr->pSitesMgmtParams->pPrimarySite;
	sitesMgmtParams_t   *pSitesMgmtParams  = pSiteMgr->pSitesMgmtParams;
	siteTablesParams_t  *pCurrentSiteTable;
    TI_BOOL              firstEmptySiteFound = TI_FALSE;
    TI_UINT32            oldestTS;


    /* choose site table according to AP's band */
    if ( RADIO_BAND_2_4_GHZ == band )
    {
        pCurrentSiteTable = &(pSitesMgmtParams->dot11BG_sitesTables);
    }
    else if (RADIO_BAND_5_0_GHZ == band)
    {
        pCurrentSiteTable = (siteTablesParams_t*) &(pSitesMgmtParams->dot11A_sitesTables);
    }
    else
    {
        TRACE1(pSiteMgr->hReport, REPORT_SEVERITY_ERROR, "Bad band: %d\n\n", band);
        pCurrentSiteTable = &(pSitesMgmtParams->dot11BG_sitesTables);
    }

    /* Set the first TS to a site which is not the Primary site */
    if (pPrimarySite != &(pCurrentSiteTable->siteTable[0]))
	{
        oldestTS = pCurrentSiteTable->siteTable[0].localTimeStamp;
    }
    else
		{
        oldestTS = pCurrentSiteTable->siteTable[1].localTimeStamp;
		}

    /* Loop all the sites till the desired MAC is found */
    for (i = 0; i < pCurrentSiteTable->maxNumOfSites; i++)
    {
        pSiteEntry = &(pCurrentSiteTable->siteTable[i]);

        if (MAC_EQUAL (pSiteEntry->bssid, *mac))
		{

            TRACE6(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "FIND success, bssid: %X-%X-%X-%X-%X-%X\n\n", (*mac)[0], (*mac)[1], (*mac)[2], (*mac)[3], (*mac)[4], (*mac)[5]);

            return pSiteEntry;
        }
        else if (pSiteEntry->siteType == SITE_NULL)
        {   /* Save the first empty site, in case the
            desired MAC is not found */
            if (!firstEmptySiteFound)
            {
                emptySiteIndex = i;
                firstEmptySiteFound=TI_TRUE;
            }

        }
        if ((oldestTS > pSiteEntry->localTimeStamp) &&
            (pSiteEntry != pPrimarySite))
        {   /* Save the oldest site's index, according to TS */
            oldestTS = pSiteEntry->localTimeStamp;
            nextSite2Remove = i;
        }
	}


    if ((!firstEmptySiteFound) || (pCurrentSiteTable->numOfSites>=pCurrentSiteTable->maxNumOfSites))
	{
		/* No NULL entry has been found. Remove the oldest site */
        pSiteEntry =  &(pCurrentSiteTable->siteTable[nextSite2Remove]);
        TRACE9(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "INSERT failure, no free entry!, numOfSites=%d, removing site index=%d,\n                                bssid: %X-%X-%X-%X-%X-%X, ts=%d \n", pCurrentSiteTable->numOfSites, nextSite2Remove, pSiteEntry->bssid[0], pSiteEntry->bssid[1], pSiteEntry->bssid[2], pSiteEntry->bssid[3], pSiteEntry->bssid[4], pSiteEntry->bssid[5], pSiteEntry->localTimeStamp);
        removeSiteEntry(pSiteMgr, pCurrentSiteTable, pSiteEntry);
        emptySiteIndex = nextSite2Remove;

	}


	pCurrentSiteTable->numOfSites++;

	pSiteEntry = &(pCurrentSiteTable->siteTable[emptySiteIndex]);

	/* fill the entry with the station mac */
	MAC_COPY (pSiteEntry->bssid, *mac);

    /* Some parameters have to be initialized immediately after entry allocation */

    if(pSiteMgr->siteMgrOperationalMode == DOT11_G_MODE)
        pSiteEntry->currentSlotTime = pSiteMgr->pDesiredParams->siteMgrDesiredSlotTime;

TRACE8(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "INSERT success, bssid: %X-%X-%X-%X-%X-%X, band=%d, index=%d\n\n", (*mac)[0], (*mac)[1], (*mac)[2], (*mac)[3], (*mac)[4], (*mac)[5], band, emptySiteIndex);


	return pSiteEntry;
}

/************************************************************************
 *                        removeSiteEntry								*
 ************************************************************************
DESCRIPTION: Removes the site entry from the site table

INPUT:      pSiteMgr		   - Handle to site mgr
            pCurrSiteTblParams - Pointer to current site table parameters
            hashPtr			   - Pointer to the site entry


OUTPUT:

RETURN:

************************************************************************/
void removeSiteEntry(siteMgr_t  *pSiteMgr,
                     siteTablesParams_t  *pCurrSiteTblParams,
                     siteEntry_t         *pSiteEntry)
{
	TI_UINT8			index;

	if (pSiteEntry == NULL)
	{
TRACE0(pSiteMgr->hReport, REPORT_SEVERITY_ERROR, "REMOVAL failure, site is NULL\n\n");
		return;
	}

	if (pCurrSiteTblParams->numOfSites == 0)
	{
TRACE0(pSiteMgr->hReport, REPORT_SEVERITY_ERROR, "REMOVAL failure, site table is empty\n\n");
		return;
	}

TRACE6(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "removeSiteEntry REMOVE ssid=, bssid= 0x%x-0x%x-0x%x-0x%x-0x%x-0x%x\n\n",			   pSiteEntry->bssid[0], pSiteEntry->bssid[1], pSiteEntry->bssid[2],			   pSiteEntry->bssid[3], pSiteEntry->bssid[4], pSiteEntry->bssid[5] );

	pCurrSiteTblParams->numOfSites--;

	/* Now remove (exclude) hashPtr entry from the linked list */

TRACE6(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, "REMOVAL success, bssid: %X-%X-%X-%X-%X-%X\n\n", pSiteEntry->bssid[0], pSiteEntry->bssid[1], pSiteEntry->bssid[2], pSiteEntry->bssid[3], pSiteEntry->bssid[4], pSiteEntry->bssid[5]);
TRACE1(pSiteMgr->hReport, REPORT_SEVERITY_INFORMATION, " SITE TABLE remaining entries number  %d \n", pCurrSiteTblParams->numOfSites);

	/* Clean the rest of the entry structure */
	index = pSiteEntry->index;     /* keep the index of the siteTable entry */
	os_memoryZero(pSiteMgr->hOs, pSiteEntry, sizeof(siteEntry_t));

    /* This is not required!!!! - Remove!!*/
	pSiteEntry->dtimPeriod = 1;
	pSiteEntry->siteType = SITE_NULL;
	pSiteEntry->index = index;   /* restore the index of the siteTable */

	/* if removing previous primary site - update the link */
	if (pSiteEntry == pSiteMgr->pSitesMgmtParams->pPrevPrimarySite)
	{
		pSiteMgr->pSitesMgmtParams->pPrevPrimarySite = NULL;
	}

	return;
}