K2.6 patches and update.

[tomato.git] / release / src-rt / emf / emf / emfc.c

/*
 * Efficient Multicast Forwarding Layer: This module does the efficient
 * layer 2 forwarding of multicast streams, i.e., forward the streams
 * only on to the ports that have corresponding group members there by
 * reducing the bandwidth utilization and latency. It uses the information
 * updated by IGMP Snooping layer to do the optimal forwarding. This file
 * contains the common code routines of EMFL.
 *
 * Copyright (C) 2010, Broadcom Corporation
 * All Rights Reserved.
 * 
 * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Broadcom Corporation;
 * the contents of this file may not be disclosed to third parties, copied
 * or duplicated in any form, in whole or in part, without the prior
 * written permission of Broadcom Corporation.
 *
 * $Id: emfc.c 241182 2011-02-17 21:50:03Z gmo $
 */
#include <typedefs.h>
#include <bcmdefs.h>
#include <bcmendian.h>
#include <proto/ethernet.h>
#include <proto/bcmip.h>
#include <osl.h>
#if defined(linux)
#include <osl_linux.h>
#else /* defined(osl_xx) */
#error "Unsupported osl"
#endif /* defined(osl_xx) */
#include <bcmutils.h>
#include "clist.h"
#include "emf_cfg.h"
#include "emfc_export.h"
#include "emfc.h"
#include "emf_export.h"

/* BH-enabled helpers */
#define EMF_RELOCK(lock) do {           \
        OSL_UNLOCK(lock);               \
        spin_lock(&((lock)->slock));    \
} while (0)
#define OSL_RELOCK(lock) do {           \
        spin_unlock(&((lock)->slock));  \
        OSL_LOCK(lock);                 \
} while (0)

static CLIST_DECL_INIT(emfc_list_head);
static osl_lock_t emfc_list_lock;

static emfc_info_t *
emfc_instance_find(char *inst_id)
{
        emfc_info_t *emfc;
        clist_head_t *ptr;

        if (inst_id == NULL)
        {
                EMF_ERROR("Invalid instance id string\n");
                return (NULL);
        }

        OSL_LOCK(emfc_list_lock);

        for (ptr = emfc_list_head.next; ptr != &emfc_list_head;
             ptr = ptr->next)
        {
                emfc = clist_entry(ptr, emfc_info_t, emfc_list);

                if (strcmp(inst_id, emfc->inst_id) == 0)
                {
                        OSL_UNLOCK(emfc_list_lock);
                        return (emfc);
                }
        }

        OSL_UNLOCK(emfc_list_lock);

        return (NULL);
}

/*
 * Description: This function is called by the IGMP snooper layer to
 *              register snooper instance with EMFL.
 *
 * Input:       inst_id - Instance identier used to associate EMF
 *                        and IGMP snooper instances.
 *              emfc    - EMFL Common code global instance handle
 *              snooper - Contains snooper specific parameters and
 *                        event callback functions. These functions
 *                        are called by EMFL on events like IGMP
 *                        packet receive, EMF enable and disable.
 *                        The snooper parameter needs to global or
 *                        persistent.
 *
 * Return:      SUCCESS or FAILURE
 */
int32
emfc_igmp_snooper_register(int8 *inst_id, emfc_info_t **emfc, emfc_snooper_t *snooper)
{
        /* Invalid input */
        if (snooper == NULL)
        {
                EMF_ERROR("Snooper parameter should be non NULL\n");
                return (FAILURE);
        }

        if (emfc == NULL)
        {
                EMF_ERROR("EMF handle should be non NULL\n");
                return (FAILURE);
        }

        /* Validate the instance id */
        if ((*emfc = emfc_instance_find(inst_id)) == NULL)
        {
                EMF_ERROR("EMF Instance doesn't exist\n");
                return (FAILURE);
        }

        if (snooper->input_fn == NULL)
        {
                EMF_ERROR("Snooper input function should be non NULL\n");
                return (FAILURE);
        }

        (*emfc)->snooper = snooper;

        return (SUCCESS);
}

/*
 * Description: This function is called by the IGMP snooper layer
 *              to unregister snooper instance.
 *
 * Input:       handle  - Handle returned during registration.
 *              snooper - Contains snooper specific parameters and
 */
void
emfc_igmp_snooper_unregister(emfc_info_t *emfc)
{
        if (emfc == NULL)
        {
                EMF_ERROR("Unregistering using invalid handle\n");
                return;
        }

        emfc->snooper = NULL;

        return;
}

/*
 * Description: This function handles the unregistered frame forwarding.
 *              IGMP frames are forwarded on router ports. Data frames
 *              are flooded on to user configured UFFP.
 *
 * Input:       emfc    - EMFC Global instance data
 *              sdu     - Pointer to packet buffer.
 *              ifp     - Interface on which the packet arrived.
 *              dest_ip - Multicast destination IP address
 *              rt_port - TRUE when the packet is received from IP
 *                        Stack otherwise FALSE.
 *
 * Return:      EMF_TAKEN - EMF has taken the ownership of the packet.
 *              EMF_NOP   - No processing needed by EMF, just return
 *                          the packet back.
 *              EMF_DROP  - Drop and free the packet.
 */
static uint32
emfc_unreg_frame_handle(emfc_info_t *emfc, void *sdu, void *ifp, uint8 proto,
                        uint32 dest_ip, bool rt_port)
{
        emfc_iflist_t *ptr;
        void *sdu_clone;
        uint32 mcast_flooded = 0;

        /* Forward the frame on to router port */
        if (!rt_port)
        {
                EMF_DEBUG("Sending frame on to router port\n");

                if ((sdu_clone = PKTDUP(emfc->osh, sdu)) == NULL)
                {
                        EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_dropped,
                                             mcast_data_dropped);
                        return (EMF_DROP);
                }

                emfc->wrapper.sendup_fn(emfc->emfi, sdu_clone);

                EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_sentup,
                                     mcast_data_sentup);
        }

        OSL_LOCK(emfc->iflist_lock);

        /* Flood the frame on to user specified ports */
        for (ptr = emfc->iflist_head; ptr != NULL; ptr = ptr->next)
        {
                int32 res;

                /* Dont forward the frame on to the port on which it
                 * was received.
                 */
                if (ifp == ptr->ifp)
                        continue;

                if (proto == IP_PROT_IGMP)
                {
                        /* Dont forward IGMP frame if the port is not router port */
                        if (ptr->rtport_ref == 0)
                                continue;
                }
                else
                {
                        /* Dont forward data frame if the port is neither router
                         * port nor uffp
                         */
                        if ((ptr->rtport_ref + ptr->uffp_ref) == 0)
                                continue;
                }

                if ((sdu_clone = PKTDUP(emfc->osh, sdu)) == NULL)
                {
                        EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_dropped,
                                             mcast_data_dropped);
                        OSL_UNLOCK(emfc->iflist_lock);
                        return (EMF_DROP);
                }

                EMF_RELOCK(emfc->iflist_lock);
                res = emfc->wrapper.forward_fn(emfc->emfi, sdu_clone, dest_ip,
                                ptr->ifp, rt_port);
                OSL_RELOCK(emfc->iflist_lock);
                if (res != SUCCESS)
                {
                        EMF_INFO("Unable to flood the unreg frame on to %s\n",
                                 DEV_IFNAME(ptr->ifp));
                        EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_dropped,
                                             mcast_data_dropped);
                }

                mcast_flooded++;
        }

        OSL_UNLOCK(emfc->iflist_lock);

        if (mcast_flooded > 0)
        {
                EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_fwd,
                                     mcast_data_flooded);
        }
        else
        {
                if (rt_port)
                {
                        EMFC_PROT_STATS_INCR(emfc, proto, igmp_frames_dropped,
                                             mcast_data_dropped);
                }
        }

        PKTFREE(emfc->osh, sdu, FALSE);

        return (EMF_TAKEN);
}

/*
 * Description: This function is called from the registered OS hook
 *              points once for every frame. This function does the
 *              MFDB lookup, packet cloning and frame forwarding.
 *
 * Input:       emfc    - EMFC Global instance data
 *              sdu     - Pointer to packet buffer.
 *              ifp     - Interface on which the packet arrived.
 *              iph     - Pointer to start of IP header.
 *              rt_port - TRUE when the packet is received from IP
 *                        Stack otherwise FALSE.
 *
 * Return:      EMF_NOP   - No processing needed by EMF, just return
 *                          the packet back.
 *              EMF_TAKEN - EMF has taken the ownership of the packet.
 *              EMF_DROP  - Drop and free the packet.
 */
uint32
emfc_input(emfc_info_t *emfc, void *sdu, void *ifp, uint8 *iph, bool rt_port)
{
        uint32 dest_ip;

        EMF_DEBUG("Received frame with dest ip %d.%d.%d.%d\n",
                  iph[IPV4_DEST_IP_OFFSET], iph[IPV4_DEST_IP_OFFSET + 1],
                  iph[IPV4_DEST_IP_OFFSET + 2], iph[IPV4_DEST_IP_OFFSET + 3]);

        dest_ip = ntoh32(*((uint32 *)(iph + IPV4_DEST_IP_OFFSET)));

        /* No processing is required if the received frame is unicast or
         * broadcast, when EMF is disabled. Send the frame back to bridge.
         */
        if ((!IP_ISMULTI(dest_ip)) || (!emfc->emf_enable))
        {
                EMF_DEBUG("Unicast frame recevied/EMF disabled\n");
                return (EMF_NOP);
        }

        /* Non-IPv4 multicast packets are not handled */
        if (IP_VER(iph) != IP_VER_4)
        {
                EMF_INFO("Non-IPv4 multicast packets will be flooded\n");
                return (EMF_NOP);
        }

        /* Check the protocol type of multicast frame */
        if ((IPV4_PROT(iph) == IP_PROT_IGMP) && (emfc->snooper != NULL))
        {
                int32 action;

                EMF_DEBUG("Received IGMP frame type %d\n", *(iph + IPV4_HLEN(iph)));

                EMFC_STATS_INCR(emfc, igmp_frames);

                /* IGMP packet received from LAN or IP Stack. Call the IGMP
                 * Snooping function. Based on the IGMP packet type it may
                 * add/delete MFDB entry.  Also the function return value
                 * tells whether to drop, forward, or flood the frame.
                 */
                ASSERT(emfc->snooper->input_fn);
                action = emfc->snooper->input_fn(emfc->snooper, ifp, iph,
                                                 iph + IPV4_HLEN(iph), rt_port);

                switch (action)
                {
                        case EMF_DROP:
                                EMF_INFO("Dropping the IGMP frame\n");
                                return (EMF_DROP);

                        case EMF_SENDUP:
                                emfc->wrapper.sendup_fn(emfc->emfi, sdu);
                                EMFC_STATS_INCR(emfc, igmp_frames_sentup);
                                return (EMF_TAKEN);

                        case EMF_FORWARD:
                                return (emfc_unreg_frame_handle(emfc, sdu, ifp,
                                                                IPV4_PROT(iph),
                                                                dest_ip, rt_port));

                        case EMF_FLOOD:
                                EMF_DEBUG("Returning the IGMP frame to bridge\n");
                                EMFC_STATS_INCR(emfc, igmp_frames_fwd);
                                break;

                        default:
                                EMF_ERROR("Unknown return value from IGMP Snooper\n");
                                EMFC_STATS_INCR(emfc, igmp_frames_fwd);
                                break;
                }

                return (EMF_NOP);
        }
        else
        {
                clist_head_t *ptr;
                emfc_mgrp_t *mgrp;
                emfc_mi_t *mi;
                void *sdu_clone;
                int32 res;

                EMF_DEBUG("Received frame with proto %d\n", IPV4_PROT(iph));

                EMFC_STATS_INCR(emfc, mcast_data_frames);

                /* Packets with destination IP address in the range 224.0.0.x
                 * must be forwarded on all ports. Similarly UPnP specific
                 * protocol traffic such as SSDP must be forwarded on to all
                 * the ports.
                 */
                if (MCAST_ADDR_LINKLOCAL(dest_ip) || MCAST_ADDR_UPNP_SSDP(dest_ip))
                {
                        EMF_DEBUG("Flooding the frames with link-local/ssdp address\n");
                        return (EMF_NOP);
                }

                OSL_LOCK(emfc->fdb_lock);

                /* Do the MFDB lookup to determine the destination port(s)
                 * to forward the frame.
                 */
                mgrp = emfc_mfdb_group_find(emfc, dest_ip);

                /* If no matching MFDB entry is found send the frame back to 
                 * bridge module so that it floods on to all the ports.
                 */
                if (mgrp == NULL)
                {
                        OSL_UNLOCK(emfc->fdb_lock);
                        EMF_DEBUG("MFDB Group entry not found\n");
                        return (emfc_unreg_frame_handle(emfc, sdu, ifp,
                                                        IPV4_PROT(iph),
                                                        dest_ip, rt_port));
                }

                ASSERT(!clist_empty(&mgrp->mi_head));

                /* If the data frame is received from one of the bridge
                 * ports then a copy has to be sent up to the router port.
                 */
                if (!rt_port)
                {
                        EMF_DEBUG("Sending to router port\n");

                        if ((sdu_clone = PKTDUP(emfc->osh, sdu)) == NULL)
                        {
                                OSL_UNLOCK(emfc->fdb_lock);
                                EMFC_STATS_INCR(emfc, mcast_data_dropped);
                                return (EMF_DROP);
                        }

                        EMF_RELOCK(emfc->fdb_lock);
                        emfc->wrapper.sendup_fn(emfc->emfi, sdu_clone);
                        OSL_RELOCK(emfc->fdb_lock);
                        EMFC_STATS_INCR(emfc, mcast_data_sentup);
                }

                /* Data frame received from LAN or IP Stack (WAN). Clone 
                 * the buffer and send on all but the last interface.
                 */
                for (ptr = mgrp->mi_head.next;
                     ptr != mgrp->mi_head.prev; ptr = ptr->next)
                {
                        mi = clist_entry(ptr, emfc_mi_t, mi_list);

                        /* Dont forward the frame on to the port on which it
                         * was received.
                         */
                        if (ifp == mi->mi_mhif->mhif_ifp)
                                continue;

                        EMF_DEBUG("Cloning the buffer for forwarding\n");

                        if ((sdu_clone = PKTDUP(emfc->osh, sdu)) == NULL)
                        {
                                OSL_UNLOCK(emfc->fdb_lock);
                                EMFC_STATS_INCR(emfc, mcast_data_dropped);
                                return (EMF_DROP);
                        }

                        EMF_RELOCK(emfc->fdb_lock);
                        res = emfc->wrapper.forward_fn(emfc->emfi, sdu_clone,
                                    dest_ip, mi->mi_mhif->mhif_ifp, rt_port);
                        OSL_RELOCK(emfc->fdb_lock);
                        res ? EMFC_STATS_INCR(emfc, mcast_data_dropped) :
                                    mi->mi_mhif->mhif_data_fwd++,
                                    mi->mi_data_fwd++;
                }

                /* Send the last frame without cloning */
                mi = clist_entry(ptr, emfc_mi_t, mi_list);

                /* Dont forward the frame on to the port on which it was received */
                if (ifp != mi->mi_mhif->mhif_ifp)
                {
                        EMF_DEBUG("Sending the original packet buffer\n");

                        EMF_RELOCK(emfc->fdb_lock);
                        res = emfc->wrapper.forward_fn(emfc->emfi, sdu, dest_ip,
                                    mi->mi_mhif->mhif_ifp, rt_port);
                        OSL_RELOCK(emfc->fdb_lock);
                        res ? EMFC_STATS_INCR(emfc, mcast_data_dropped) :
                                    mi->mi_mhif->mhif_data_fwd++,
                                    mi->mi_data_fwd++;
                }
                else
                {
                        EMF_DEBUG("Freeing the original packet buffer\n");
                        PKTFREE(emfc->osh, sdu, FALSE);
                }

                EMFC_STATS_INCR(emfc, mcast_data_fwd);

                OSL_UNLOCK(emfc->fdb_lock);

                return (EMF_TAKEN);
        }
}

/*
 * Description: This function initializes the MFDB. MFDB group
 *              entries are organized as a hash table with chaining
 *              for collision resolution. Each MFDB group entry
 *              points to the chain of MFDB interface entries that are
 *              members of the group.
 *
 * Input:       emfc - EMFL Common code global data handle
 */
static void
emfc_mfdb_init(emfc_info_t *emfc)
{
        int32 i;

        /* Initialize the multicast forwarding database */
        for (i = 0; i < MFDB_HASHT_SIZE; i++)
        {
                clist_init_head(&emfc->mgrp_fdb[i]);
        }

        /* Initialize the multicast interface list. This list contains
         * all the interfaces that have multicast group members. Entries in
         * this list are never expired/deleted. Each entry maintains stats
         * specific to the interface.
         */
        emfc->mhif_head = NULL;

        return;
}

/*
 * Description: This function does the MFDB lookup to locate interface
 *              entry of the specified group.
 *
 * Input:       emfc - EMFL Common code global data handle
 *              mgrp - Pointer to multicast group entry of MFDB
 *              ifp  - Interface pointer to locate.
 *
 * Return:      Returns pointer to the MFDB interface entry, NULL
 *              otherwise.
 */
static emfc_mi_t *
emfc_mfdb_mi_entry_find(emfc_info_t *emfc, emfc_mgrp_t *mgrp, void *ifp)
{
        emfc_mi_t *mi;
        clist_head_t *ptr;

        ASSERT(mgrp);

        for (ptr = mgrp->mi_head.next;
             ptr != &mgrp->mi_head; ptr = ptr->next)
        {
                mi = clist_entry(ptr, emfc_mi_t, mi_list);
                if (ifp == mi->mi_mhif->mhif_ifp)
                {
                        return (mi);
                }
        }

        return (NULL);
}

/*
 * Description: This function does the MFDB lookup to locate a multicast
 *              group entry.
 *
 * Input:       emfc    - EMFL Common code global data handle
 *              mgrp_ip - Multicast group address of the entry.
 *
 * Return:      Returns NULL is no group entry is found. Otherwise
 *              returns pointer to the MFDB group entry.
 */
static emfc_mgrp_t *
emfc_mfdb_group_find(emfc_info_t *emfc, uint32 mgrp_ip)
{
        uint32 hash;
        emfc_mgrp_t *mgrp;
        clist_head_t *ptr;

        ASSERT(IP_ISMULTI(mgrp_ip));

        /* Do the cache lookup first. Since the multicast video traffic
         * is bursty in nature there is a good chance that the cache
         * hit ratio will be good. If during the testing we find that
         * the hit ratio is not as good then this single entry cache
         * mechanism will be removed.
         */
        if (mgrp_ip == emfc->mgrp_cache_ip)
        {
                EMFC_STATS_INCR(emfc, mfdb_cache_hits);
                return (emfc->mgrp_cache);
        }

        EMFC_STATS_INCR(emfc, mfdb_cache_misses);

        hash = MFDB_MGRP_HASH(mgrp_ip);

        for (ptr = emfc->mgrp_fdb[hash].next;
             ptr != &emfc->mgrp_fdb[hash];
             ptr = ptr->next)
        {
                mgrp = clist_entry(ptr, emfc_mgrp_t, mgrp_hlist);

                /* Compare group address */
                if (mgrp_ip == mgrp->mgrp_ip)
                {
                        EMF_MFDB("Multicast Group entry %d.%d.%d.%d found\n",
                                 (mgrp_ip >> 24), ((mgrp_ip >> 16) & 0xff),
                                 ((mgrp_ip >> 8) & 0xff), (mgrp_ip & 0xff));
                        emfc->mgrp_cache = mgrp;
                        emfc->mgrp_cache_ip = mgrp_ip;
                        return (mgrp);
                }
        }

        return (NULL);
}

/*
 * Add the entry if not present otherwise return the pointer to
 * the entry.
 */
emfc_mhif_t *
emfc_mfdb_mhif_add(emfc_info_t *emfc, void *ifp)
{
        emfc_mhif_t *ptr, *mhif;

        for (ptr = emfc->mhif_head; ptr != NULL; ptr = ptr->next)
        {
                if (ptr->mhif_ifp == ifp)
                {
                        return (ptr);
                }
        }

        /* Add new entry */
        mhif = MALLOC(emfc->osh, sizeof(emfc_mhif_t));
        if (mhif == NULL)
        {
                EMF_ERROR("Failed to alloc mem size %d for mhif entry\n",
                          sizeof(emfc_mhif_t));
                return (NULL);
        }

        mhif->mhif_ifp = ifp;
        mhif->mhif_data_fwd = 0;
        mhif->next = emfc->mhif_head;
        emfc->mhif_head = mhif;

        return (mhif);
}

/*
 * Description: This function does the MFDB lookup to locate a interface
 *              entry of the specified multicast group.
 *
 * Input:       emfc    - EMFL Common code global data handle
 *              mgrp_ip - Multicast group IP address of the entry.
 *              ifp     - Pointer to the interface on which the member
 *                        is present.
 *
 * Return:      Returns NULL is no interface entry is found. Otherwise
 *              returns pointer to the MFDB interface entry.
 */
emfc_mi_t *
emfc_mfdb_membership_find(emfc_info_t *emfc, uint32 mgrp_ip, void *ifp)
{
        emfc_mi_t *mi;
        emfc_mgrp_t *mgrp;

        ASSERT(IP_ISMULTI(mgrp_ip));

        OSL_LOCK(emfc->fdb_lock);

        /* Find group entry */
        mgrp = emfc_mfdb_group_find(emfc, mgrp_ip);

        if (mgrp != NULL)
        {
                /* Find interface entry */
                mi = emfc_mfdb_mi_entry_find(emfc, mgrp, ifp);
                if (mi != NULL)
                {
                        EMF_MFDB("Interface entry %d.%d.%d.%d:%p found\n",
                                 (mgrp_ip >> 24), ((mgrp_ip >> 16) & 0xff),
                                 ((mgrp_ip >> 8) & 0xff), (mgrp_ip & 0xff), ifp);
                        return (mi);
                }
        }

        OSL_UNLOCK(emfc->fdb_lock);

        EMF_MFDB("Interface entry %x %p not found\n", mgrp_ip, ifp);

        return (NULL);
}

/*
 * Description: This function is called by IGMP Snooper when it wants
 *              to add MFDB entry or refresh the entry. This function
 *              is also called by the management application to add a
 *              static MFDB entry.
 *
 *              If the MFDB entry is not present, it allocates group
 *              entry, interface entry and links them together.
 *
 * Input:       Same as above function.
 *
 * Return:      SUCCESS or FAILURE
 */
int32
emfc_mfdb_membership_add(emfc_info_t *emfc, uint32 mgrp_ip, void *ifp)
{
        uint32 hash;
        emfc_mgrp_t *mgrp;
        emfc_mi_t *mi;

        ASSERT(IP_ISMULTI(mgrp_ip));

        OSL_LOCK(emfc->fdb_lock);

        /* If the group entry doesn't exist, add a new entry and update
         * the member/interface information.
         */
        mgrp = emfc_mfdb_group_find(emfc, mgrp_ip);

        if (mgrp == NULL)
        {
                /* Allocate and initialize multicast group entry */
                mgrp = MALLOC(emfc->osh, sizeof(emfc_mgrp_t));
                if (mgrp == NULL)
                {
                        EMF_ERROR("Failed to alloc mem size %d for group entry\n",
                                  sizeof(emfc_mgrp_t));
                        OSL_UNLOCK(emfc->fdb_lock);
                        return (FAILURE);
                }

                mgrp->mgrp_ip = mgrp_ip;
                clist_init_head(&mgrp->mi_head);

                EMF_MFDB("Adding group entry %d.%d.%d.%d\n",
                         (mgrp_ip >> 24), ((mgrp_ip >> 16) & 0xff),
                         ((mgrp_ip >> 8) & 0xff), (mgrp_ip & 0xff));

                /* Add the group entry to hash table */
                hash = MFDB_MGRP_HASH(mgrp_ip);
                clist_add_head(&emfc->mgrp_fdb[hash], &mgrp->mgrp_hlist);
        }
        else
        {
                mi = emfc_mfdb_mi_entry_find(emfc, mgrp, ifp);

                /* Update the ref count */
                if (mi != NULL)
                {
                        mi->mi_ref++;
                        OSL_UNLOCK(emfc->fdb_lock);
                        return (SUCCESS);
                }
        }

        EMF_MFDB("Adding interface entry for interface %p\n", ifp);

        /* Allocate and initialize multicast interface entry */
        mi = MALLOC(emfc->osh, sizeof(emfc_mi_t));
        if (mi == NULL)
        {
                EMF_ERROR("Failed to allocated memory %d for interface entry\n",
                          sizeof(emfc_mi_t));
                if (clist_empty(&mgrp->mi_head))
                {
                        clist_delete(&mgrp->mgrp_hlist);
                        emfc->mgrp_cache_ip = ((emfc->mgrp_cache == mgrp) ?
                                               0 : emfc->mgrp_cache_ip);
                        MFREE(emfc->osh, mgrp, sizeof(emfc_mgrp_t));
                }
                OSL_UNLOCK(emfc->fdb_lock);
                return (FAILURE);
        }

        /* Initialize the multicast interface list entry */
        mi->mi_ref = 1;
        mi->mi_mhif = emfc_mfdb_mhif_add(emfc, ifp);
        mi->mi_data_fwd = 0;

        /* Add the multicast interface entry */
        clist_add_head(&mgrp->mi_head, &mi->mi_list);

        OSL_UNLOCK(emfc->fdb_lock);

        return (SUCCESS);
}

/*
 * Description: This function is called by the IGMP snooper layer
 *              to delete the MFDB entry. It deletes the group
 *              entry also if the interface entry is last in the
 *              group.
 *
 * Input:       Same as above function.
 *
 * Return:      SUCCESS or FAILURE
 */
int32
emfc_mfdb_membership_del(emfc_info_t *emfc, uint32 mgrp_ip, void *ifp)
{
        emfc_mi_t *mi;
        emfc_mgrp_t *mgrp;

        OSL_LOCK(emfc->fdb_lock);

        /* Find group entry */
        mgrp = emfc_mfdb_group_find(emfc, mgrp_ip);

        if (mgrp == NULL)
        {
                OSL_UNLOCK(emfc->fdb_lock);
                return (FAILURE);
        }

        /* Find interface entry */
        mi = emfc_mfdb_mi_entry_find(emfc, mgrp, ifp);

        if (mi == NULL)
        {
                OSL_UNLOCK(emfc->fdb_lock);
                return (FAILURE);
        }

        EMF_MFDB("Deleting MFDB interface entry for interface %p\n", ifp);

        /* Delete the interface entry when ref count reaches zero */
        mi->mi_ref--;
        if (mi->mi_ref != 0)
        {
                OSL_UNLOCK(emfc->fdb_lock);
                return (SUCCESS);
        }
        else
        {
                EMF_MFDB("Deleting interface entry %p\n", mi->mi_mhif->mhif_ifp);
                clist_delete(&mi->mi_list);
        }

        /* If the member being deleted is last node in the interface list, 
         * delete the group entry also.
         */
        if (clist_empty(&mgrp->mi_head))
        {
                EMF_MFDB("Deleting group entry of %d.%d.%d.%d too\n",
                         (mgrp_ip >> 24), ((mgrp_ip >> 16) & 0xff),
                         ((mgrp_ip >> 8) & 0xff), (mgrp_ip & 0xff));

                clist_delete(&mgrp->mgrp_hlist);
                emfc->mgrp_cache_ip = ((emfc->mgrp_cache == mgrp) ?
                                       0 : emfc->mgrp_cache_ip);
                MFREE(emfc->osh, mgrp, sizeof(emfc_mgrp_t));
        }

        MFREE(emfc->osh, mi, sizeof(emfc_mi_t));

        OSL_UNLOCK(emfc->fdb_lock);

        return (SUCCESS);
}

/*
 * Description: This function clears the group interval timers and
 *              deletes the group and interface entries of the MFDB.
 *
 * Input:       emfc     - EMFL Common code global data handle
 */
void
emfc_mfdb_clear(emfc_info_t *emfc)
{
        uint32 i;
        emfc_mgrp_t *mgrp;
        emfc_mi_t *mi;
        clist_head_t *ptr1, *ptr2, *tmp1, *tmp2;

        OSL_LOCK(emfc->fdb_lock);

        /* Delete all the group entries */
        for (i = 0; i < MFDB_HASHT_SIZE; i++)
        {
                for (ptr1 = emfc->mgrp_fdb[i].next;
                     ptr1 != &emfc->mgrp_fdb[i]; ptr1 = tmp1)
                {
                        mgrp = clist_entry(ptr1, emfc_mgrp_t, mgrp_hlist);

                        /* Delete all interface entries */
                        for (ptr2 = mgrp->mi_head.next;
                             ptr2 != &mgrp->mi_head; ptr2 = tmp2)
                        {
                                mi = clist_entry(ptr2, emfc_mi_t, mi_list);

                                tmp2 = ptr2->next;
                                EMF_MFDB("Deleting interface entry %p\n", mi);
                                clist_delete(ptr2);
                                MFREE(emfc->osh, mi, sizeof(emfc_mi_t));
                        }

                        tmp1 = ptr1->next;

                        /* Delete the group entry when there are no more interface
                         * entries for this group.
                         */
                        clist_delete(ptr1);
                        MFREE(emfc->osh, mgrp, sizeof(emfc_mgrp_t));
                }
        }

        emfc->mgrp_cache_ip = 0;

        OSL_UNLOCK(emfc->fdb_lock);

        return;
}

/*
 * EMFC Interface List cleanup
 */
static void
emfc_iflist_clear(emfc_info_t *emfc)
{
        emfc_iflist_t *ptr, *temp;

        OSL_LOCK(emfc->iflist_lock);

        ptr = emfc->iflist_head;
        while (ptr != NULL)
        {
                temp = ptr->next;
                MFREE(emfc->osh, ptr, sizeof(emfc_iflist_t));
                ptr = temp;
        }

        emfc->iflist_head = NULL;

        OSL_UNLOCK(emfc->iflist_lock);

        return;
}

/*
 * Description:  This function is called to enable/disable the efficient
 *               multicast forwarding feature. When the config operation
 *               cannot be completed respective status is returned.
 *
 * Input:        emfc - EMFL Common code global data handle
 *
 * Input/Output: cfg  - Pointer to configuration request data. It contains
 *                      the command id, operation type, corresponding
 *                      arguments and output status.
 */
static void
emfc_cfg_emf_enable(emfc_info_t *emfc, emf_cfg_request_t *cfg)
{
        bool emf_enable;

        EMF_DEBUG("Operation type: %d\n", cfg->oper_type);

        switch (cfg->oper_type)
        {
                case EMFCFG_OPER_TYPE_GET:
                        *(bool *)cfg->arg = emfc->emf_enable;
                        cfg->size = sizeof(bool);
                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_OPER_TYPE_SET:
                        /* Enable or disable EMF */
                        emf_enable = (*(bool *)cfg->arg ? TRUE : FALSE);
                        if (emfc->emf_enable == emf_enable)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size = sprintf(cfg->arg,
                                                    "Duplicate configuration request\n");
                                break;
                        }

                        emfc->emf_enable = emf_enable;

                        if (emfc->emf_enable)
                        {
                                /* Register the hooks to start receiving multicast frames */
                                if (emfc->wrapper.hooks_register_fn(emfc->emfi) != SUCCESS)
                                {
                                        cfg->status = EMFCFG_STATUS_FAILURE;
                                        cfg->size = sprintf(cfg->arg,
                                                            "Duplicate hooks registration\n");
                                        break;
                                }

                                /* Call the registered EMF enable entry point function */
                                if (emfc->snooper && emfc->snooper->emf_enable_fn != NULL)
                                {
                                        EMF_DEBUG("Calling the EMF enable function\n");
                                        emfc->snooper->emf_enable_fn(emfc->snooper);
                                }
                        }
                        else
                        {
                                /* Call the registered EMF disable entry point function */
                                if (emfc->snooper && emfc->snooper->emf_disable_fn != NULL)
                                {
                                        EMF_DEBUG("Calling the EMF disable function\n");
                                        emfc->snooper->emf_disable_fn(emfc->snooper);
                                }

                                /* Unregister the packet hooks first */
                                emfc->wrapper.hooks_unregister_fn(emfc->emfi);

                                /* Cleanup the MFDB entries */
                                emfc_mfdb_clear(emfc);

                                /* Cleanup the UFFP entries */
                                emfc_iflist_clear(emfc);
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                default:
                        cfg->status = EMFCFG_STATUS_OPER_UNKNOWN;
                        cfg->size = sprintf(cfg->arg, "Unknown operation\n");
                        break;
        }

        return;
}

/*
 * EMFL Packet Counters/Statistics
 */
int32
emfc_stats_get(emfc_info_t *emfc, emf_stats_t *emfs, uint32 size)
{
        if (emfc == NULL)
        {
                EMF_ERROR("Invalid EMFC handle passed\n");
                return (FAILURE);
        }

        if (emfs == NULL)
        {
                EMF_ERROR("Invalid buffer input\n");
                return (FAILURE);
        }

        if (size < sizeof(emf_stats_t))
        {
                EMF_ERROR("Insufficient buffer size %d\n", size);
                return (FAILURE);
        }

        *emfs = emfc->stats;

        return (SUCCESS);
}

/*
 * MFDB Listing Function
 */
int32
emfc_mfdb_list(emfc_info_t *emfc, emf_cfg_mfdb_list_t *list, uint32 size)
{
        clist_head_t *ptr1, *ptr2;
        emfc_mi_t *mi;
        emfc_mgrp_t *mgrp;
        int32 i, index = 0;

        if (emfc == NULL)
        {
                EMF_ERROR("Invalid EMFC handle passed\n");
                return (FAILURE);
        }

        if (list == NULL)
        {
                EMF_ERROR("Invalid buffer input\n");
                return (FAILURE);
        }

        for (i = 0; i < MFDB_HASHT_SIZE; i++)
        {
                for (ptr1 = emfc->mgrp_fdb[i].next;
                     ptr1 != &emfc->mgrp_fdb[i]; ptr1 = ptr1->next)
                {
                        mgrp = clist_entry(ptr1, emfc_mgrp_t, mgrp_hlist);
                        for (ptr2 = mgrp->mi_head.next;
                             ptr2 != &mgrp->mi_head; ptr2 = ptr2->next)
                        {
                                mi = clist_entry(ptr2, emfc_mi_t, mi_list);

                                list->mfdb_entry[index].mgrp_ip = mgrp->mgrp_ip;
                                strncpy(list->mfdb_entry[index].if_name,
                                        DEV_IFNAME(mi->mi_mhif->mhif_ifp), 16);
                                list->mfdb_entry[index].pkts_fwd = mi->mi_data_fwd;
                                index++;
                        }
                }
        }

        /* Update the total number of entries */
        list->num_entries = index;

        return (SUCCESS);
}

/*
 * EMFC Interface List find
 */
static emfc_iflist_t *
emfc_iflist_find(emfc_info_t *emfc, void *ifp, emfc_iflist_t **prev)
{
        emfc_iflist_t *ptr;

        OSL_LOCK(emfc->iflist_lock);

        *prev = NULL;
        for (ptr = emfc->iflist_head; ptr != NULL;
             *prev = ptr, ptr = ptr->next)
        {
                if (ptr->ifp == ifp)
                {
                        OSL_UNLOCK(emfc->iflist_lock);
                        return (ptr);
                }
        }

        OSL_UNLOCK(emfc->iflist_lock);

        return (NULL);
}

/*
 * EMFC Interface List add entry
 */
int32
emfc_iflist_add(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *iflist, *prev;

        if (ifp == NULL)
        {
                EMF_ERROR("Invalid interface identifier\n");
                return (FAILURE);
        }

        if (emfc_iflist_find(emfc, ifp, &prev) != NULL)
        {
                EMF_DEBUG("Adding duplicate interface entry\n");
                return (FAILURE);
        }

        /* Allocate and initialize UFFP entry */
        iflist = MALLOC(emfc->osh, sizeof(emfc_iflist_t));
        if (iflist == NULL)
        {
                EMF_ERROR("Failed to alloc mem size %d for interface entry\n",
                          sizeof(emfc_iflist_t));
                return (FAILURE);
        }

        iflist->ifp = ifp;
        iflist->uffp_ref = 0;
        iflist->rtport_ref = 0;

        /* Add the UFFP entry to the list */
        OSL_LOCK(emfc->iflist_lock);
        iflist->next = emfc->iflist_head;
        emfc->iflist_head = iflist;
        OSL_UNLOCK(emfc->iflist_lock);

        return (SUCCESS);
}

/*
 * EMFC Interface List delete entry
 */
int32
emfc_iflist_del(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *ptr, *prev;

        if (ifp == NULL)
        {
                EMF_ERROR("Invalid interface identifier\n");
                return (FAILURE);
        }

        if ((ptr = emfc_iflist_find(emfc, ifp, &prev)) == NULL)
        {
                EMF_ERROR("UFFP entry not found\n");
                return (FAILURE);
        }

        OSL_LOCK(emfc->iflist_lock);

        /* Delete the UFFP entry from the list */
        if (prev != NULL)
                prev->next = ptr->next;
        else
                emfc->iflist_head = ptr->next;

        OSL_UNLOCK(emfc->iflist_lock);

        MFREE(emfc->osh, ptr, sizeof(emfc_iflist_t));

        return (SUCCESS);
}

/*
 * UFFP add entry
 */
static int32
emfc_uffp_add(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *iflist, *prev;

        /* Add the interface entry if not present already */
        emfc_iflist_add(emfc, ifp);

        OSL_LOCK(emfc->iflist_lock);
        if ((iflist = emfc_iflist_find(emfc, ifp, &prev)) != NULL)
                iflist->uffp_ref++;
        OSL_UNLOCK(emfc->iflist_lock);

        return (SUCCESS);
}

/*
 * UFFP delete entry
 */
static int32
emfc_uffp_del(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *iflist, *prev;

        if ((iflist = emfc_iflist_find(emfc, ifp, &prev)) == NULL)
                return (FAILURE);

        /* Delete the interface entry when flags is zero */
        OSL_LOCK(emfc->iflist_lock);
        iflist->uffp_ref--;
        if ((iflist->uffp_ref == 0) && (iflist->rtport_ref == 0))
                emfc_iflist_del(emfc, ifp);
        OSL_UNLOCK(emfc->iflist_lock);

        return (SUCCESS);
}

/*
 * UFFP Interface Listing
 */
static int32
emfc_uffp_list(emfc_info_t *emfc, emf_cfg_uffp_list_t *list, uint32 size)
{
        int32 index = 0, bytes = 0;
        emfc_iflist_t *ptr;

        for (ptr = emfc->iflist_head; ptr != NULL; ptr = ptr->next)
        {
                if (ptr->uffp_ref == 0)
                        continue;

                bytes += sizeof(emf_cfg_uffp_t);
                if (bytes > size)
                        return (FAILURE);

                strncpy(list->uffp_entry[index].if_name, DEV_IFNAME(ptr->ifp), 16);
                list->uffp_entry[index].if_name[15] = 0;
                index++;
        }

        /* Update the total number of entries */
        list->num_entries = index;

        return (SUCCESS);
}

/*
 * Description: This function is called by the IGMP Snooper to add a Router
 *              Port. Router Port is the interface on which the IGMP Snooper
 *              determines that a multicast router is present. We set a bit
 *              in the flag field of the interface list entry to mark it as
 *              router port.
 *
 * Input:       emfc - EMFC Global Instance handle
 *              ifp  - Interface pointer
 *
 * Return:      SUCCESS/FAILURE
 */
int32
emfc_rtport_add(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *iflist, *prev;

        /* Add interface list entry */
        emfc_iflist_add(emfc, ifp);

        OSL_LOCK(emfc->iflist_lock);
        if ((iflist = emfc_iflist_find(emfc, ifp, &prev)) != NULL)
                iflist->rtport_ref++;
        OSL_UNLOCK(emfc->iflist_lock);

        EMF_INFO("RTPORT %s added refcount %d\n", DEV_IFNAME(ifp), iflist->rtport_ref);

        return (SUCCESS);
}

/*
 * Description: This function is called by the IGMP Snooper to delete a
 *              Router Port. We clear the corresponding bit in the flags
 *              field to mark the port as non-router port.
 *
 * Input:       emfc - EMFC Global Instance handle
 *              ifp  - Interface pointer
 *
 * Return:      SUCCESS/FAILURE
 */
int32
emfc_rtport_del(emfc_info_t *emfc, void *ifp)
{
        emfc_iflist_t *iflist, *prev;

        if ((iflist = emfc_iflist_find(emfc, ifp, &prev)) == NULL)
        {
                EMF_ERROR("Invalid interface specified to rtport delete\n");
                return (FAILURE);
        }

        /* Delete the interface entry when flags is zero */
        OSL_LOCK(emfc->iflist_lock);
        iflist->rtport_ref--;
        if ((iflist->rtport_ref == 0) && (iflist->uffp_ref == 0))
                emfc_iflist_del(emfc, ifp);
        OSL_UNLOCK(emfc->iflist_lock);

        return (SUCCESS);
}

/*
 * RTPORT listing function
 */
static int32
emfc_rtport_list(emfc_info_t *emfc, emf_cfg_rtport_list_t *list, uint32 size)
{
        int32 index = 0, bytes = 0;
        emfc_iflist_t *ptr;

        for (ptr = emfc->iflist_head; ptr != NULL; ptr = ptr->next)
        {
                if (ptr->rtport_ref == 0)
                        continue;

                bytes += sizeof(emf_cfg_rtport_t);
                if (bytes > size)
                        return (FAILURE);

                strncpy(list->rtport_entry[index].if_name, DEV_IFNAME(ptr->ifp), 16);
                list->rtport_entry[index].if_name[15] = 0;
                index++;
        }

        /* Update the total number of entries */
        list->num_entries = index;

        return (SUCCESS);
}

/*
 * Description: This function is called from the OS Specific layer when the
 *              user issues a configuration command.
 *
 * Input/Output: Same as emfc_cfg_emf_enable.
 */
void
emfc_cfg_request_process(emfc_info_t *emfc, emf_cfg_request_t *cfg)
{
        emf_cfg_mfdb_t *mfdb;
        emf_cfg_uffp_t *uffp;
        emf_cfg_rtport_t *rtport;

        EMF_DEBUG("Command identifier: %d\n", cfg->command_id);

        switch (cfg->command_id)
        {
                case EMFCFG_CMD_EMF_ENABLE:
                        emfc_cfg_emf_enable(emfc, cfg);
                        break;

                case EMFCFG_CMD_MFDB_ADD:
                        mfdb = (emf_cfg_mfdb_t *)cfg->arg;
                        cfg->size = 0;

                        /* Add MFDB entry for this group and interface */
                        if (emfc_mfdb_membership_add(emfc, mfdb->mgrp_ip,
                                                     mfdb->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg, "Unable to add entry\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;

                        EMF_MFDB("MFDB entry %x %p added by user\n",
                                 mfdb->mgrp_ip, mfdb->if_ptr);
                        break;

                case EMFCFG_CMD_MFDB_DEL:
                        mfdb = (emf_cfg_mfdb_t *)cfg->arg;
                        cfg->size = 0;

                        /* Delete MFDB entry */
                        if (emfc_mfdb_membership_del(emfc, mfdb->mgrp_ip,
                                                     mfdb->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg, "MFDB entry not found\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;

                        EMF_MFDB("MFDB entry %x %p deleted by user\n",
                                 mfdb->mgrp_ip, mfdb->if_ptr);
                        break;

                case EMFCFG_CMD_MFDB_LIST:
                        if (emfc_mfdb_list(emfc, (emf_cfg_mfdb_list_t *)cfg->arg,
                                           cfg->size) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg, "MFDB list get failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_MFDB_CLEAR:
                        emfc_mfdb_clear(emfc);
                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_RTPORT_ADD:
                        rtport = (emf_cfg_rtport_t *)cfg->arg;
                        cfg->size = 0;

                        if (emfc_rtport_add(emfc, rtport->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg,
                                                     "Unknown interface, rtport add failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_RTPORT_DEL:
                        rtport = (emf_cfg_rtport_t *)cfg->arg;
                        cfg->size = 0;

                        if (emfc_rtport_del(emfc, rtport->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg,
                                                     "Unknown interface, rtport del failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_RTPORT_LIST:
                        if (emfc_rtport_list(emfc, (emf_cfg_rtport_list_t *)cfg->arg,
                                             cfg->size) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size = sprintf(cfg->arg, "rtport list get failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_UFFP_ADD:
                        uffp = (emf_cfg_uffp_t *)cfg->arg;
                        cfg->size = 0;

                        if (emfc_uffp_add(emfc, uffp->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg,
                                                     "Unknown interface, UFFP add failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_UFFP_DEL:
                        uffp = (emf_cfg_uffp_t *)cfg->arg;
                        cfg->size = 0;

                        if (emfc_uffp_del(emfc, uffp->if_ptr) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size += sprintf(cfg->arg,
                                                     "Unknown interface, UFFP del failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_UFFP_LIST:
                        if (emfc_uffp_list(emfc, (emf_cfg_uffp_list_t *)cfg->arg,
                                           cfg->size) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size = sprintf(cfg->arg, "UFFP list get failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                case EMFCFG_CMD_EMF_STATS:
                        if (emfc_stats_get(emfc, (emf_stats_t *)cfg->arg,
                                           cfg->size) != SUCCESS)
                        {
                                cfg->status = EMFCFG_STATUS_FAILURE;
                                cfg->size = sprintf(cfg->arg, "EMF stats get failed\n");
                                break;
                        }

                        cfg->status = EMFCFG_STATUS_SUCCESS;
                        break;

                default:
                        EMF_DEBUG("Unknown command %d\n", cfg->command_id);
                        cfg->status = EMFCFG_STATUS_CMD_UNKNOWN;
                        cfg->size = sprintf(cfg->arg, "Unknown command\n");
                        break;
        }

        return;
}

/*
 * Description: This function is called from the OS specific module init
 *              routine to create and initialize EMFC instance. This function
 *              primarily initializes the EMFL global data and MFDB.
 *
 * Input:       inst_id - Instance identier used to associate EMF
 *                        and IGMP snooper instances.
 *              emfi    - EMFL OS Specific global data handle
 *              osh     - OS abstraction layer handle
 *              wrapper - EMFC wrapper info
 *
 * Return:      emfc    - EMFL Common code global data handle
 */
emfc_info_t *
emfc_init(int8 *inst_id, void *emfi, osl_t *osh, emfc_wrapper_t *wrapper)
{
        emfc_info_t *emfc;

        EMF_DEBUG("Initializing EMFL\n");

        /* Check for the wrapper parameter */
        if (wrapper == NULL)
        {
                EMF_ERROR("emfc_init: wrapper parameter NULL\n");
                return (NULL);
        }

        /* Allocate memory */
        emfc = MALLOC(osh, sizeof(emfc_info_t));
        if (emfc == NULL)
        {
                EMF_ERROR("Failed to allocated memory size %d for MFL\n",
                          sizeof(emfc_info_t));
                return (NULL);
        }

        EMF_DEBUG("Allocated memory for EMFC info\n");

        /* Initialize the EMF global data */
        bzero(emfc, sizeof(emfc_info_t));
        emfc->osh = osh;
        emfc->emfi = emfi;
        emfc->mgrp_cache_ip = 0;
        emfc->mgrp_cache = NULL;
        emfc->iflist_head = NULL;

        /* Set EMF status as disabled */
        emfc->emf_enable = FALSE;

        /* Initialize Multicast FDB */
        emfc_mfdb_init(emfc);

        /* Create lock for MFDB access */
        emfc->fdb_lock = OSL_LOCK_CREATE("FDB Lock");
        if (emfc->fdb_lock == NULL)
        {
                MFREE(emfc->osh, emfc, sizeof(emfc_info_t));
                return (NULL);
        }

        /* Create lock for router port list access */
        emfc->iflist_lock = OSL_LOCK_CREATE("Router Port List Lock");
        if (emfc->iflist_lock == NULL)
        {
                OSL_LOCK_DESTROY(emfc->fdb_lock);
                MFREE(emfc->osh, emfc, sizeof(emfc_info_t));
                return (NULL);
        }

        /* Save the instance id */
        strncpy(emfc->inst_id, inst_id, IFNAMSIZ);
        emfc->inst_id[IFNAMSIZ - 1] = 0;

        /* Fill up the wrapper specific functions */
        emfc->wrapper.forward_fn = wrapper->forward_fn;
        emfc->wrapper.sendup_fn = wrapper->sendup_fn;
        emfc->wrapper.hooks_register_fn = wrapper->hooks_register_fn;
        emfc->wrapper.hooks_unregister_fn = wrapper->hooks_unregister_fn;

        /* Add to the EMFC instance list */
        OSL_LOCK(emfc_list_lock);
        clist_add_head(&emfc_list_head, &emfc->emfc_list);
        OSL_UNLOCK(emfc_list_lock);

        EMF_DEBUG("Initialized MFDB\n");

        return (emfc);
}

/*
 * Description: This function is called from OS specific module cleanup
 *              routine. This routine primarily clears the MFDB entries
 *              and frees the global instance data.
 *
 * Input:       emfc - EMFL global instance handle
 */
void
emfc_exit(emfc_info_t *emfc)
{
        emfc_mhif_t *ptr, *temp;

        /* Unregister the packet hooks if not already */
        emfc->wrapper.hooks_unregister_fn(emfc->emfi);

        /* Cleanup MFDB entries */
        emfc_mfdb_clear(emfc);

        /* Cleanup the interface list entries */
        emfc_iflist_clear(emfc);
        OSL_LOCK_DESTROY(emfc->iflist_lock);

        OSL_LOCK(emfc->fdb_lock);

        /* Delete interface list */
        ptr = emfc->mhif_head;
        while (ptr != NULL)
        {
                temp = ptr->next;
                MFREE(emfc->osh, ptr, sizeof(emfc_mhif_t));
                ptr = temp;
        }

        OSL_UNLOCK(emfc->fdb_lock);

        OSL_LOCK_DESTROY(emfc->fdb_lock);

        /* Delete the EMFC instance */
        OSL_LOCK(emfc_list_lock);
        clist_delete(&emfc->emfc_list);
        OSL_UNLOCK(emfc_list_lock);

        MFREE(emfc->osh, emfc, sizeof(emfc_info_t));

        EMF_DEBUG("Cleaned up EMFL, exiting common code\n");

        return;
}

/*
 * Description: This function is called from OS specific module init
 *              routine. This allocates global resources required by the
 *              common code.
 */
int32
emfc_module_init(void)
{
        /* Create lock for EMFC instance list access */
        emfc_list_lock = OSL_LOCK_CREATE("EMFC List Lock");

        if (emfc_list_lock == NULL)
        {
                EMF_ERROR("EMFC List lock create failed\n");
                return (FAILURE);
        }

        return (SUCCESS);
}

/*
 * Description: This function is called from OS specific module cleanup
 *              routine. This frees all the global resources.
 */
void
emfc_module_exit(void)
{
        OSL_LOCK_DESTROY(emfc_list_lock);
        return;
}