irlmp.c

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/*********************************************************************
 *
 * Filename:      irlmp.c
 * Version:       1.0
 * Description:   IrDA Link Management Protocol (LMP) layer
 * Status:        Stable.
 * Author:        Dag Brattli <[email protected]>
 * Created at:    Sun Aug 17 20:54:32 1997
 * Modified at:   Wed Jan  5 11:26:03 2000
 * Modified by:   Dag Brattli <[email protected]>
 *
 *     Copyright (c) 1998-2000 Dag Brattli <[email protected]>,
 *     All Rights Reserved.
 *     Copyright (c) 2000-2003 Jean Tourrilhes <[email protected]>
 *
 *     This program is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of
 *     the License, or (at your option) any later version.
 *
 *     Neither Dag Brattli nor University of Tromsø admit liability nor
 *     provide warranty for any of this software. This material is
 *     provided "AS-IS" and at no charge.
 *
 ********************************************************************/

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/random.h>
#include <linux/seq_file.h>

#include <net/irda/irda.h>
#include <net/irda/timer.h>
#include <net/irda/qos.h>
#include <net/irda/irlap.h>
#include <net/irda/iriap.h>
#include <net/irda/irlmp.h>
#include <net/irda/irlmp_frame.h>

#include <asm/unaligned.h>

static __u8 irlmp_find_free_slsap(void);
static int irlmp_slsap_inuse(__u8 slsap_sel);

/* Master structure */
struct irlmp_cb *irlmp = NULL;

/* These can be altered by the sysctl interface */
int  sysctl_discovery         = 0;
int  sysctl_discovery_timeout = 3; /* 3 seconds by default */
int  sysctl_discovery_slots   = 6; /* 6 slots by default */
int  sysctl_lap_keepalive_time = LM_IDLE_TIMEOUT * 1000 / HZ;
char sysctl_devname[65];

const char *irlmp_reasons[] = {
    "ERROR, NOT USED",
    "LM_USER_REQUEST",
    "LM_LAP_DISCONNECT",
    "LM_CONNECT_FAILURE",
    "LM_LAP_RESET",
    "LM_INIT_DISCONNECT",
    "ERROR, NOT USED",
};

/*
 * Function irlmp_init (void)
 *
 *    Create (allocate) the main IrLMP structure
 *
 */
int __init irlmp_init(void)
{
    IRDA_DEBUG(1, "%s()\n", __func__);
    /* Initialize the irlmp structure. */
    irlmp = kzalloc( sizeof(struct irlmp_cb), GFP_KERNEL);
    if (irlmp == NULL)
        return -ENOMEM;

    irlmp->magic = LMP_MAGIC;

    irlmp->clients = hashbin_new(HB_LOCK);
    irlmp->services = hashbin_new(HB_LOCK);
    irlmp->links = hashbin_new(HB_LOCK);
    irlmp->unconnected_lsaps = hashbin_new(HB_LOCK);
    irlmp->cachelog = hashbin_new(HB_NOLOCK);

    if ((irlmp->clients == NULL) ||
        (irlmp->services == NULL) ||
        (irlmp->links == NULL) ||
        (irlmp->unconnected_lsaps == NULL) ||
        (irlmp->cachelog == NULL)) {
        return -ENOMEM;
    }

    spin_lock_init(&irlmp->cachelog->hb_spinlock);

    irlmp->last_lsap_sel = 0x0f; /* Reserved 0x00-0x0f */
    strcpy(sysctl_devname, "Linux");

    init_timer(&irlmp->discovery_timer);

    /* Do discovery every 3 seconds, conditionally */
    if (sysctl_discovery)
        irlmp_start_discovery_timer(irlmp,
                        sysctl_discovery_timeout*HZ);

    return 0;
}

/*
 * Function irlmp_cleanup (void)
 *
 *    Remove IrLMP layer
 *
 */
void irlmp_cleanup(void)
{
    /* Check for main structure */
    IRDA_ASSERT(irlmp != NULL, return;);
    IRDA_ASSERT(irlmp->magic == LMP_MAGIC, return;);

    del_timer(&irlmp->discovery_timer);

    hashbin_delete(irlmp->links, (FREE_FUNC) kfree);
    hashbin_delete(irlmp->unconnected_lsaps, (FREE_FUNC) kfree);
    hashbin_delete(irlmp->clients, (FREE_FUNC) kfree);
    hashbin_delete(irlmp->services, (FREE_FUNC) kfree);
    hashbin_delete(irlmp->cachelog, (FREE_FUNC) kfree);

    /* De-allocate main structure */
    kfree(irlmp);
    irlmp = NULL;
}

/*
 * Function irlmp_open_lsap (slsap, notify)
 *
 *   Register with IrLMP and create a local LSAP,
 *   returns handle to LSAP.
 */
struct lsap_cb *irlmp_open_lsap(__u8 slsap_sel, notify_t *notify, __u8 pid)
{
    struct lsap_cb *self;

    IRDA_ASSERT(notify != NULL, return NULL;);
    IRDA_ASSERT(irlmp != NULL, return NULL;);
    IRDA_ASSERT(irlmp->magic == LMP_MAGIC, return NULL;);
    IRDA_ASSERT(notify->instance != NULL, return NULL;);

    /*  Does the client care which Source LSAP selector it gets?  */
    if (slsap_sel == LSAP_ANY) {
        slsap_sel = irlmp_find_free_slsap();
        if (!slsap_sel)
            return NULL;
    } else if (irlmp_slsap_inuse(slsap_sel))
        return NULL;

    /* Allocate new instance of a LSAP connection */
    self = kzalloc(sizeof(struct lsap_cb), GFP_ATOMIC);
    if (self == NULL) {
        IRDA_ERROR("%s: can't allocate memory\n", __func__);
        return NULL;
    }

    self->magic = LMP_LSAP_MAGIC;
    self->slsap_sel = slsap_sel;

    /* Fix connectionless LSAP's */
    if (slsap_sel == LSAP_CONNLESS) {
#ifdef CONFIG_IRDA_ULTRA
        self->dlsap_sel = LSAP_CONNLESS;
        self->pid = pid;
#endif /* CONFIG_IRDA_ULTRA */
    } else
        self->dlsap_sel = LSAP_ANY;
    /* self->connected = FALSE; -> already NULL via memset() */

    init_timer(&self->watchdog_timer);

    self->notify = *notify;

    self->lsap_state = LSAP_DISCONNECTED;

    /* Insert into queue of unconnected LSAPs */
    hashbin_insert(irlmp->unconnected_lsaps, (irda_queue_t *) self,
               (long) self, NULL);

    return self;
}
EXPORT_SYMBOL(irlmp_open_lsap);

/*
 * Function __irlmp_close_lsap (self)
 *
 *    Remove an instance of LSAP
 */
static void __irlmp_close_lsap(struct lsap_cb *self)
{
    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);

    /*
     *  Set some of the variables to preset values
     */
    self->magic = 0;
    del_timer(&self->watchdog_timer); /* Important! */

    if (self->conn_skb)
        dev_kfree_skb(self->conn_skb);

    kfree(self);
}

/*
 * Function irlmp_close_lsap (self)
 *
 *    Close and remove LSAP
 *
 */
void irlmp_close_lsap(struct lsap_cb *self)
{
    struct lap_cb *lap;
    struct lsap_cb *lsap = NULL;

    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);

    /*
     *  Find out if we should remove this LSAP from a link or from the
     *  list of unconnected lsaps (not associated with a link)
     */
    lap = self->lap;
    if (lap) {
        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);
        /* We might close a LSAP before it has completed the
         * connection setup. In those case, higher layers won't
         * send a proper disconnect request. Harmless, except
         * that we will forget to close LAP... - Jean II */
        if(self->lsap_state != LSAP_DISCONNECTED) {
            self->lsap_state = LSAP_DISCONNECTED;
            irlmp_do_lap_event(self->lap,
                       LM_LAP_DISCONNECT_REQUEST, NULL);
        }
        /* Now, remove from the link */
        lsap = hashbin_remove(lap->lsaps, (long) self, NULL);
#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
        lap->cache.valid = FALSE;
#endif
    }
    self->lap = NULL;
    /* Check if we found the LSAP! If not then try the unconnected lsaps */
    if (!lsap) {
        lsap = hashbin_remove(irlmp->unconnected_lsaps, (long) self,
                      NULL);
    }
    if (!lsap) {
        IRDA_DEBUG(0,
             "%s(), Looks like somebody has removed me already!\n",
               __func__);
        return;
    }
    __irlmp_close_lsap(self);
}
EXPORT_SYMBOL(irlmp_close_lsap);

/*
 * Function irlmp_register_irlap (saddr, notify)
 *
 *    Register IrLAP layer with IrLMP. There is possible to have multiple
 *    instances of the IrLAP layer, each connected to different IrDA ports
 *
 */
void irlmp_register_link(struct irlap_cb *irlap, __u32 saddr, notify_t *notify)
{
    struct lap_cb *lap;

    IRDA_ASSERT(irlmp != NULL, return;);
    IRDA_ASSERT(irlmp->magic == LMP_MAGIC, return;);
    IRDA_ASSERT(notify != NULL, return;);

    /*
     *  Allocate new instance of a LSAP connection
     */
    lap = kzalloc(sizeof(struct lap_cb), GFP_KERNEL);
    if (lap == NULL) {
        IRDA_ERROR("%s: unable to kmalloc\n", __func__);
        return;
    }

    lap->irlap = irlap;
    lap->magic = LMP_LAP_MAGIC;
    lap->saddr = saddr;
    lap->daddr = DEV_ADDR_ANY;
#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
    lap->cache.valid = FALSE;
#endif
    lap->lsaps = hashbin_new(HB_LOCK);
    if (lap->lsaps == NULL) {
        IRDA_WARNING("%s(), unable to kmalloc lsaps\n", __func__);
        kfree(lap);
        return;
    }

    lap->lap_state = LAP_STANDBY;

    init_timer(&lap->idle_timer);

    /*
     *  Insert into queue of LMP links
     */
    hashbin_insert(irlmp->links, (irda_queue_t *) lap, lap->saddr, NULL);

    /*
     *  We set only this variable so IrLAP can tell us on which link the
     *  different events happened on
     */
    irda_notify_init(notify);
    notify->instance = lap;
}

/*
 * Function irlmp_unregister_irlap (saddr)
 *
 *    IrLAP layer has been removed!
 *
 */
void irlmp_unregister_link(__u32 saddr)
{
    struct lap_cb *link;

    IRDA_DEBUG(4, "%s()\n", __func__);

    /* We must remove ourselves from the hashbin *first*. This ensure
     * that no more LSAPs will be open on this link and no discovery
     * will be triggered anymore. Jean II */
    link = hashbin_remove(irlmp->links, saddr, NULL);
    if (link) {
        IRDA_ASSERT(link->magic == LMP_LAP_MAGIC, return;);

        /* Kill all the LSAPs on this link. Jean II */
        link->reason = LAP_DISC_INDICATION;
        link->daddr = DEV_ADDR_ANY;
        irlmp_do_lap_event(link, LM_LAP_DISCONNECT_INDICATION, NULL);

        /* Remove all discoveries discovered at this link */
        irlmp_expire_discoveries(irlmp->cachelog, link->saddr, TRUE);

        /* Final cleanup */
        del_timer(&link->idle_timer);
        link->magic = 0;
        hashbin_delete(link->lsaps, (FREE_FUNC) __irlmp_close_lsap);
        kfree(link);
    }
}

/*
 * Function irlmp_connect_request (handle, dlsap, userdata)
 *
 *    Connect with a peer LSAP
 *
 */
int irlmp_connect_request(struct lsap_cb *self, __u8 dlsap_sel,
              __u32 saddr, __u32 daddr,
              struct qos_info *qos, struct sk_buff *userdata)
{
    struct sk_buff *tx_skb = userdata;
    struct lap_cb *lap;
    struct lsap_cb *lsap;
    int ret;

    IRDA_ASSERT(self != NULL, return -EBADR;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -EBADR;);

    IRDA_DEBUG(2,
          "%s(), slsap_sel=%02x, dlsap_sel=%02x, saddr=%08x, daddr=%08x\n",
          __func__, self->slsap_sel, dlsap_sel, saddr, daddr);

    if (test_bit(0, &self->connected)) {
        ret = -EISCONN;
        goto err;
    }

    /* Client must supply destination device address */
    if (!daddr) {
        ret = -EINVAL;
        goto err;
    }

    /* Any userdata? */
    if (tx_skb == NULL) {
        tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
        if (!tx_skb)
            return -ENOMEM;

        skb_reserve(tx_skb, LMP_MAX_HEADER);
    }

    /* Make room for MUX control header (3 bytes) */
    IRDA_ASSERT(skb_headroom(tx_skb) >= LMP_CONTROL_HEADER, return -1;);
    skb_push(tx_skb, LMP_CONTROL_HEADER);

    self->dlsap_sel = dlsap_sel;

    /*
     * Find the link to where we should try to connect since there may
     * be more than one IrDA port on this machine. If the client has
     * passed us the saddr (and already knows which link to use), then
     * we use that to find the link, if not then we have to look in the
     * discovery log and check if any of the links has discovered a
     * device with the given daddr
     */
    if ((!saddr) || (saddr == DEV_ADDR_ANY)) {
        discovery_t *discovery;
        unsigned long flags;

        spin_lock_irqsave(&irlmp->cachelog->hb_spinlock, flags);
        if (daddr != DEV_ADDR_ANY)
            discovery = hashbin_find(irlmp->cachelog, daddr, NULL);
        else {
            IRDA_DEBUG(2, "%s(), no daddr\n", __func__);
            discovery = (discovery_t *)
                hashbin_get_first(irlmp->cachelog);
        }

        if (discovery) {
            saddr = discovery->data.saddr;
            daddr = discovery->data.daddr;
        }
        spin_unlock_irqrestore(&irlmp->cachelog->hb_spinlock, flags);
    }
    lap = hashbin_lock_find(irlmp->links, saddr, NULL);
    if (lap == NULL) {
        IRDA_DEBUG(1, "%s(), Unable to find a usable link!\n", __func__);
        ret = -EHOSTUNREACH;
        goto err;
    }

    /* Check if LAP is disconnected or already connected */
    if (lap->daddr == DEV_ADDR_ANY)
        lap->daddr = daddr;
    else if (lap->daddr != daddr) {
        /* Check if some LSAPs are active on this LAP */
        if (HASHBIN_GET_SIZE(lap->lsaps) == 0) {
            /* No active connection, but LAP hasn't been
             * disconnected yet (waiting for timeout in LAP).
             * Maybe we could give LAP a bit of help in this case.
             */
            IRDA_DEBUG(0, "%s(), sorry, but I'm waiting for LAP to timeout!\n", __func__);
            ret = -EAGAIN;
            goto err;
        }

        /* LAP is already connected to a different node, and LAP
         * can only talk to one node at a time */
        IRDA_DEBUG(0, "%s(), sorry, but link is busy!\n", __func__);
        ret = -EBUSY;
        goto err;
    }

    self->lap = lap;

    /*
     *  Remove LSAP from list of unconnected LSAPs and insert it into the
     *  list of connected LSAPs for the particular link
     */
    lsap = hashbin_remove(irlmp->unconnected_lsaps, (long) self, NULL);

    IRDA_ASSERT(lsap != NULL, return -1;);
    IRDA_ASSERT(lsap->magic == LMP_LSAP_MAGIC, return -1;);
    IRDA_ASSERT(lsap->lap != NULL, return -1;);
    IRDA_ASSERT(lsap->lap->magic == LMP_LAP_MAGIC, return -1;);

    hashbin_insert(self->lap->lsaps, (irda_queue_t *) self, (long) self,
               NULL);

    set_bit(0, &self->connected);   /* TRUE */

    /*
     *  User supplied qos specifications?
     */
    if (qos)
        self->qos = *qos;

    irlmp_do_lsap_event(self, LM_CONNECT_REQUEST, tx_skb);

    /* Drop reference count - see irlap_data_request(). */
    dev_kfree_skb(tx_skb);

    return 0;

err:
    /* Cleanup */
    if(tx_skb)
        dev_kfree_skb(tx_skb);
    return ret;
}
EXPORT_SYMBOL(irlmp_connect_request);

/*
 * Function irlmp_connect_indication (self)
 *
 *    Incoming connection
 *
 */
void irlmp_connect_indication(struct lsap_cb *self, struct sk_buff *skb)
{
    int max_seg_size;
    int lap_header_size;
    int max_header_size;

    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);
    IRDA_ASSERT(skb != NULL, return;);
    IRDA_ASSERT(self->lap != NULL, return;);

    IRDA_DEBUG(2, "%s(), slsap_sel=%02x, dlsap_sel=%02x\n",
           __func__, self->slsap_sel, self->dlsap_sel);

    /* Note : self->lap is set in irlmp_link_data_indication(),
     * (case CONNECT_CMD:) because we have no way to set it here.
     * Similarly, self->dlsap_sel is usually set in irlmp_find_lsap().
     * Jean II */

    self->qos = *self->lap->qos;

    max_seg_size = self->lap->qos->data_size.value-LMP_HEADER;
    lap_header_size = IRLAP_GET_HEADER_SIZE(self->lap->irlap);
    max_header_size = LMP_HEADER + lap_header_size;

    /* Hide LMP_CONTROL_HEADER header from layer above */
    skb_pull(skb, LMP_CONTROL_HEADER);

    if (self->notify.connect_indication) {
        /* Don't forget to refcount it - see irlap_driver_rcv(). */
        skb_get(skb);
        self->notify.connect_indication(self->notify.instance, self,
                        &self->qos, max_seg_size,
                        max_header_size, skb);
    }
}

/*
 * Function irlmp_connect_response (handle, userdata)
 *
 *    Service user is accepting connection
 *
 */
int irlmp_connect_response(struct lsap_cb *self, struct sk_buff *userdata)
{
    IRDA_ASSERT(self != NULL, return -1;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);
    IRDA_ASSERT(userdata != NULL, return -1;);

    /* We set the connected bit and move the lsap to the connected list
     * in the state machine itself. Jean II */

    IRDA_DEBUG(2, "%s(), slsap_sel=%02x, dlsap_sel=%02x\n",
           __func__, self->slsap_sel, self->dlsap_sel);

    /* Make room for MUX control header (3 bytes) */
    IRDA_ASSERT(skb_headroom(userdata) >= LMP_CONTROL_HEADER, return -1;);
    skb_push(userdata, LMP_CONTROL_HEADER);

    irlmp_do_lsap_event(self, LM_CONNECT_RESPONSE, userdata);

    /* Drop reference count - see irlap_data_request(). */
    dev_kfree_skb(userdata);

    return 0;
}
EXPORT_SYMBOL(irlmp_connect_response);

/*
 * Function irlmp_connect_confirm (handle, skb)
 *
 *    LSAP connection confirmed peer device!
 */
void irlmp_connect_confirm(struct lsap_cb *self, struct sk_buff *skb)
{
    int max_header_size;
    int lap_header_size;
    int max_seg_size;

    IRDA_DEBUG(3, "%s()\n", __func__);

    IRDA_ASSERT(skb != NULL, return;);
    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);
    IRDA_ASSERT(self->lap != NULL, return;);

    self->qos = *self->lap->qos;

    max_seg_size    = self->lap->qos->data_size.value-LMP_HEADER;
    lap_header_size = IRLAP_GET_HEADER_SIZE(self->lap->irlap);
    max_header_size = LMP_HEADER + lap_header_size;

    IRDA_DEBUG(2, "%s(), max_header_size=%d\n",
           __func__, max_header_size);

    /* Hide LMP_CONTROL_HEADER header from layer above */
    skb_pull(skb, LMP_CONTROL_HEADER);

    if (self->notify.connect_confirm) {
        /* Don't forget to refcount it - see irlap_driver_rcv() */
        skb_get(skb);
        self->notify.connect_confirm(self->notify.instance, self,
                         &self->qos, max_seg_size,
                         max_header_size, skb);
    }
}

/*
 * Function irlmp_dup (orig, instance)
 *
 *    Duplicate LSAP, can be used by servers to confirm a connection on a
 *    new LSAP so it can keep listening on the old one.
 *
 */
struct lsap_cb *irlmp_dup(struct lsap_cb *orig, void *instance)
{
    struct lsap_cb *new;
    unsigned long flags;

    IRDA_DEBUG(1, "%s()\n", __func__);

    spin_lock_irqsave(&irlmp->unconnected_lsaps->hb_spinlock, flags);

    /* Only allowed to duplicate unconnected LSAP's, and only LSAPs
     * that have received a connect indication. Jean II */
    if ((!hashbin_find(irlmp->unconnected_lsaps, (long) orig, NULL)) ||
        (orig->lap == NULL)) {
        IRDA_DEBUG(0, "%s(), invalid LSAP (wrong state)\n",
               __func__);
        spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock,
                       flags);
        return NULL;
    }

    /* Allocate a new instance */
    new = kmemdup(orig, sizeof(*new), GFP_ATOMIC);
    if (!new)  {
        IRDA_DEBUG(0, "%s(), unable to kmalloc\n", __func__);
        spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock,
                       flags);
        return NULL;
    }
    /* new->lap = orig->lap; => done in the memcpy() */
    /* new->slsap_sel = orig->slsap_sel; => done in the memcpy() */
    new->conn_skb = NULL;

    spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);

    /* Not everything is the same */
    new->notify.instance = instance;

    init_timer(&new->watchdog_timer);

    hashbin_insert(irlmp->unconnected_lsaps, (irda_queue_t *) new,
               (long) new, NULL);

#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
    /* Make sure that we invalidate the LSAP cache */
    new->lap->cache.valid = FALSE;
#endif /* CONFIG_IRDA_CACHE_LAST_LSAP */

    return new;
}

/*
 * Function irlmp_disconnect_request (handle, userdata)
 *
 *    The service user is requesting disconnection, this will not remove the
 *    LSAP, but only mark it as disconnected
 */
int irlmp_disconnect_request(struct lsap_cb *self, struct sk_buff *userdata)
{
    struct lsap_cb *lsap;

    IRDA_ASSERT(self != NULL, return -1;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);
    IRDA_ASSERT(userdata != NULL, return -1;);

    /* Already disconnected ?
     * There is a race condition between irlmp_disconnect_indication()
     * and us that might mess up the hashbins below. This fixes it.
     * Jean II */
    if (! test_and_clear_bit(0, &self->connected)) {
        IRDA_DEBUG(0, "%s(), already disconnected!\n", __func__);
        dev_kfree_skb(userdata);
        return -1;
    }

    skb_push(userdata, LMP_CONTROL_HEADER);

    /*
     *  Do the event before the other stuff since we must know
     *  which lap layer that the frame should be transmitted on
     */
    irlmp_do_lsap_event(self, LM_DISCONNECT_REQUEST, userdata);

    /* Drop reference count - see irlap_data_request(). */
    dev_kfree_skb(userdata);

    /*
     *  Remove LSAP from list of connected LSAPs for the particular link
     *  and insert it into the list of unconnected LSAPs
     */
    IRDA_ASSERT(self->lap != NULL, return -1;);
    IRDA_ASSERT(self->lap->magic == LMP_LAP_MAGIC, return -1;);
    IRDA_ASSERT(self->lap->lsaps != NULL, return -1;);

    lsap = hashbin_remove(self->lap->lsaps, (long) self, NULL);
#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
    self->lap->cache.valid = FALSE;
#endif

    IRDA_ASSERT(lsap != NULL, return -1;);
    IRDA_ASSERT(lsap->magic == LMP_LSAP_MAGIC, return -1;);
    IRDA_ASSERT(lsap == self, return -1;);

    hashbin_insert(irlmp->unconnected_lsaps, (irda_queue_t *) self,
               (long) self, NULL);

    /* Reset some values */
    self->dlsap_sel = LSAP_ANY;
    self->lap = NULL;

    return 0;
}
EXPORT_SYMBOL(irlmp_disconnect_request);

/*
 * Function irlmp_disconnect_indication (reason, userdata)
 *
 *    LSAP is being closed!
 */
void irlmp_disconnect_indication(struct lsap_cb *self, LM_REASON reason,
                 struct sk_buff *skb)
{
    struct lsap_cb *lsap;

    IRDA_DEBUG(1, "%s(), reason=%s\n", __func__, irlmp_reasons[reason]);
    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);

    IRDA_DEBUG(3, "%s(), slsap_sel=%02x, dlsap_sel=%02x\n",
           __func__, self->slsap_sel, self->dlsap_sel);

    /* Already disconnected ?
     * There is a race condition between irlmp_disconnect_request()
     * and us that might mess up the hashbins below. This fixes it.
     * Jean II */
    if (! test_and_clear_bit(0, &self->connected)) {
        IRDA_DEBUG(0, "%s(), already disconnected!\n", __func__);
        return;
    }

    /*
     *  Remove association between this LSAP and the link it used
     */
    IRDA_ASSERT(self->lap != NULL, return;);
    IRDA_ASSERT(self->lap->lsaps != NULL, return;);

    lsap = hashbin_remove(self->lap->lsaps, (long) self, NULL);
#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
    self->lap->cache.valid = FALSE;
#endif

    IRDA_ASSERT(lsap != NULL, return;);
    IRDA_ASSERT(lsap == self, return;);
    hashbin_insert(irlmp->unconnected_lsaps, (irda_queue_t *) lsap,
               (long) lsap, NULL);

    self->dlsap_sel = LSAP_ANY;
    self->lap = NULL;

    /*
     *  Inform service user
     */
    if (self->notify.disconnect_indication) {
        /* Don't forget to refcount it - see irlap_driver_rcv(). */
        if(skb)
            skb_get(skb);
        self->notify.disconnect_indication(self->notify.instance,
                           self, reason, skb);
    } else {
        IRDA_DEBUG(0, "%s(), no handler\n", __func__);
    }
}

/*
 * Function irlmp_do_expiry (void)
 *
 *    Do a cleanup of the discovery log (remove old entries)
 *
 * Note : separate from irlmp_do_discovery() so that we can handle
 * passive discovery properly.
 */
void irlmp_do_expiry(void)
{
    struct lap_cb *lap;

    /*
     * Expire discovery on all links which are *not* connected.
     * On links which are connected, we can't do discovery
     * anymore and can't refresh the log, so we freeze the
     * discovery log to keep info about the device we are
     * connected to.
     * This info is mandatory if we want irlmp_connect_request()
     * to work properly. - Jean II
     */
    lap = (struct lap_cb *) hashbin_get_first(irlmp->links);
    while (lap != NULL) {
        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);

        if (lap->lap_state == LAP_STANDBY) {
            /* Expire discoveries discovered on this link */
            irlmp_expire_discoveries(irlmp->cachelog, lap->saddr,
                         FALSE);
        }
        lap = (struct lap_cb *) hashbin_get_next(irlmp->links);
    }
}

/*
 * Function irlmp_do_discovery (nslots)
 *
 *    Do some discovery on all links
 *
 * Note : log expiry is done above.
 */
void irlmp_do_discovery(int nslots)
{
    struct lap_cb *lap;
    __u16 *data_hintsp;

    /* Make sure the value is sane */
    if ((nslots != 1) && (nslots != 6) && (nslots != 8) && (nslots != 16)){
        IRDA_WARNING("%s: invalid value for number of slots!\n",
                 __func__);
        nslots = sysctl_discovery_slots = 8;
    }

    /* Construct new discovery info to be used by IrLAP, */
    data_hintsp = (__u16 *) irlmp->discovery_cmd.data.hints;
    put_unaligned(irlmp->hints.word, data_hintsp);

    /*
     *  Set character set for device name (we use ASCII), and
     *  copy device name. Remember to make room for a \0 at the
     *  end
     */
    irlmp->discovery_cmd.data.charset = CS_ASCII;
    strncpy(irlmp->discovery_cmd.data.info, sysctl_devname,
        NICKNAME_MAX_LEN);
    irlmp->discovery_cmd.name_len = strlen(irlmp->discovery_cmd.data.info);
    irlmp->discovery_cmd.nslots = nslots;

    /*
     * Try to send discovery packets on all links
     */
    lap = (struct lap_cb *) hashbin_get_first(irlmp->links);
    while (lap != NULL) {
        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);

        if (lap->lap_state == LAP_STANDBY) {
            /* Try to discover */
            irlmp_do_lap_event(lap, LM_LAP_DISCOVERY_REQUEST,
                       NULL);
        }
        lap = (struct lap_cb *) hashbin_get_next(irlmp->links);
    }
}

/*
 * Function irlmp_discovery_request (nslots)
 *
 *    Do a discovery of devices in front of the computer
 *
 * If the caller has registered a client discovery callback, this
 * allow him to receive the full content of the discovery log through
 * this callback (as normally he will receive only new discoveries).
 */
void irlmp_discovery_request(int nslots)
{
    /* Return current cached discovery log (in full) */
    irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_LOG);

    /*
     * Start a single discovery operation if discovery is not already
     * running
     */
    if (!sysctl_discovery) {
        /* Check if user wants to override the default */
        if (nslots == DISCOVERY_DEFAULT_SLOTS)
            nslots = sysctl_discovery_slots;

        irlmp_do_discovery(nslots);
        /* Note : we never do expiry here. Expiry will run on the
         * discovery timer regardless of the state of sysctl_discovery
         * Jean II */
    }
}
EXPORT_SYMBOL(irlmp_discovery_request);

/*
 * Function irlmp_get_discoveries (pn, mask, slots)
 *
 *    Return the current discovery log
 *
 * If discovery is not enabled, you should call this function again
 * after 1 or 2 seconds (i.e. after discovery has been done).
 */
struct irda_device_info *irlmp_get_discoveries(int *pn, __u16 mask, int nslots)
{
    /* If discovery is not enabled, it's likely that the discovery log
     * will be empty. So, we trigger a single discovery, so that next
     * time the user call us there might be some results in the log.
     * Jean II
     */
    if (!sysctl_discovery) {
        /* Check if user wants to override the default */
        if (nslots == DISCOVERY_DEFAULT_SLOTS)
            nslots = sysctl_discovery_slots;

        /* Start discovery - will complete sometime later */
        irlmp_do_discovery(nslots);
        /* Note : we never do expiry here. Expiry will run on the
         * discovery timer regardless of the state of sysctl_discovery
         * Jean II */
    }

    /* Return current cached discovery log */
    return irlmp_copy_discoveries(irlmp->cachelog, pn, mask, TRUE);
}
EXPORT_SYMBOL(irlmp_get_discoveries);

/*
 * Function irlmp_notify_client (log)
 *
 *    Notify all about discovered devices
 *
 * Clients registered with IrLMP are :
 *  o IrComm
 *  o IrLAN
 *  o Any socket (in any state - ouch, that may be a lot !)
 * The client may have defined a callback to be notified in case of
 * partial/selective discovery based on the hints that it passed to IrLMP.
 */
static inline void
irlmp_notify_client(irlmp_client_t *client,
            hashbin_t *log, DISCOVERY_MODE mode)
{
    discinfo_t *discoveries;    /* Copy of the discovery log */
    int number;         /* Number of nodes in the log */
    int i;

    IRDA_DEBUG(3, "%s()\n", __func__);

    /* Check if client wants or not partial/selective log (optimisation) */
    if (!client->disco_callback)
        return;

    /*
     * Locking notes :
     * the old code was manipulating the log directly, which was
     * very racy. Now, we use copy_discoveries, that protects
     * itself while dumping the log for us.
     * The overhead of the copy is compensated by the fact that
     * we only pass new discoveries in normal mode and don't
     * pass the same old entry every 3s to the caller as we used
     * to do (virtual function calling is expensive).
     * Jean II
     */

    /*
     * Now, check all discovered devices (if any), and notify client
     * only about the services that the client is interested in
     * We also notify only about the new devices unless the caller
     * explicitly request a dump of the log. Jean II
     */
    discoveries = irlmp_copy_discoveries(log, &number,
                         client->hint_mask.word,
                         (mode == DISCOVERY_LOG));
    /* Check if the we got some results */
    if (discoveries == NULL)
        return; /* No nodes discovered */

    /* Pass all entries to the listener */
    for(i = 0; i < number; i++)
        client->disco_callback(&(discoveries[i]), mode, client->priv);

    /* Free up our buffer */
    kfree(discoveries);
}

/*
 * Function irlmp_discovery_confirm ( self, log)
 *
 *    Some device(s) answered to our discovery request! Check to see which
 *    device it is, and give indication to the client(s)
 *
 */
void irlmp_discovery_confirm(hashbin_t *log, DISCOVERY_MODE mode)
{
    irlmp_client_t *client;
    irlmp_client_t *client_next;

    IRDA_DEBUG(3, "%s()\n", __func__);

    IRDA_ASSERT(log != NULL, return;);

    if (!(HASHBIN_GET_SIZE(log)))
        return;

    /* For each client - notify callback may touch client list */
    client = (irlmp_client_t *) hashbin_get_first(irlmp->clients);
    while (NULL != hashbin_find_next(irlmp->clients, (long) client, NULL,
                     (void *) &client_next) ) {
        /* Check if we should notify client */
        irlmp_notify_client(client, log, mode);

        client = client_next;
    }
}

/*
 * Function irlmp_discovery_expiry (expiry)
 *
 *  This device is no longer been discovered, and therefore it is being
 *  purged from the discovery log. Inform all clients who have
 *  registered for this event...
 *
 *  Note : called exclusively from discovery.c
 *  Note : this is no longer called under discovery spinlock, so the
 *      client can do whatever he wants in the callback.
 */
void irlmp_discovery_expiry(discinfo_t *expiries, int number)
{
    irlmp_client_t *client;
    irlmp_client_t *client_next;
    int     i;

    IRDA_DEBUG(3, "%s()\n", __func__);

    IRDA_ASSERT(expiries != NULL, return;);

    /* For each client - notify callback may touch client list */
    client = (irlmp_client_t *) hashbin_get_first(irlmp->clients);
    while (NULL != hashbin_find_next(irlmp->clients, (long) client, NULL,
                     (void *) &client_next) ) {

        /* Pass all entries to the listener */
        for(i = 0; i < number; i++) {
            /* Check if we should notify client */
            if ((client->expir_callback) &&
                (client->hint_mask.word &
                 get_unaligned((__u16 *)expiries[i].hints)
                 & 0x7f7f) )
                client->expir_callback(&(expiries[i]),
                               EXPIRY_TIMEOUT,
                               client->priv);
        }

        /* Next client */
        client = client_next;
    }
}

/*
 * Function irlmp_get_discovery_response ()
 *
 *    Used by IrLAP to get the discovery info it needs when answering
 *    discovery requests by other devices.
 */
discovery_t *irlmp_get_discovery_response(void)
{
    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(irlmp != NULL, return NULL;);

    put_unaligned(irlmp->hints.word, (__u16 *)irlmp->discovery_rsp.data.hints);

    /*
     *  Set character set for device name (we use ASCII), and
     *  copy device name. Remember to make room for a \0 at the
     *  end
     */
    irlmp->discovery_rsp.data.charset = CS_ASCII;

    strncpy(irlmp->discovery_rsp.data.info, sysctl_devname,
        NICKNAME_MAX_LEN);
    irlmp->discovery_rsp.name_len = strlen(irlmp->discovery_rsp.data.info);

    return &irlmp->discovery_rsp;
}

/*
 * Function irlmp_data_request (self, skb)
 *
 *    Send some data to peer device
 *
 * Note on skb management :
 * After calling the lower layers of the IrDA stack, we always
 * kfree() the skb, which drop the reference count (and potentially
 * destroy it).
 * IrLMP and IrLAP may queue the packet, and in those cases will need
 * to use skb_get() to keep it around.
 * Jean II
 */
int irlmp_data_request(struct lsap_cb *self, struct sk_buff *userdata)
{
    int ret;

    IRDA_ASSERT(self != NULL, return -1;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -1;);

    /* Make room for MUX header */
    IRDA_ASSERT(skb_headroom(userdata) >= LMP_HEADER, return -1;);
    skb_push(userdata, LMP_HEADER);

    ret = irlmp_do_lsap_event(self, LM_DATA_REQUEST, userdata);

    /* Drop reference count - see irlap_data_request(). */
    dev_kfree_skb(userdata);

    return ret;
}
EXPORT_SYMBOL(irlmp_data_request);

/*
 * Function irlmp_data_indication (handle, skb)
 *
 *    Got data from LAP layer so pass it up to upper layer
 *
 */
void irlmp_data_indication(struct lsap_cb *self, struct sk_buff *skb)
{
    /* Hide LMP header from layer above */
    skb_pull(skb, LMP_HEADER);

    if (self->notify.data_indication) {
        /* Don't forget to refcount it - see irlap_driver_rcv(). */
        skb_get(skb);
        self->notify.data_indication(self->notify.instance, self, skb);
    }
}

/*
 * Function irlmp_udata_request (self, skb)
 */
int irlmp_udata_request(struct lsap_cb *self, struct sk_buff *userdata)
{
    int ret;

    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(userdata != NULL, return -1;);

    /* Make room for MUX header */
    IRDA_ASSERT(skb_headroom(userdata) >= LMP_HEADER, return -1;);
    skb_push(userdata, LMP_HEADER);

    ret = irlmp_do_lsap_event(self, LM_UDATA_REQUEST, userdata);

    /* Drop reference count - see irlap_data_request(). */
    dev_kfree_skb(userdata);

    return ret;
}

/*
 * Function irlmp_udata_indication (self, skb)
 *
 *    Send unreliable data (but still within the connection)
 *
 */
void irlmp_udata_indication(struct lsap_cb *self, struct sk_buff *skb)
{
    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);
    IRDA_ASSERT(skb != NULL, return;);

    /* Hide LMP header from layer above */
    skb_pull(skb, LMP_HEADER);

    if (self->notify.udata_indication) {
        /* Don't forget to refcount it - see irlap_driver_rcv(). */
        skb_get(skb);
        self->notify.udata_indication(self->notify.instance, self,
                          skb);
    }
}

/*
 * Function irlmp_connless_data_request (self, skb)
 */
#ifdef CONFIG_IRDA_ULTRA
int irlmp_connless_data_request(struct lsap_cb *self, struct sk_buff *userdata,
                __u8 pid)
{
    struct sk_buff *clone_skb;
    struct lap_cb *lap;

    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(userdata != NULL, return -1;);

    /* Make room for MUX and PID header */
    IRDA_ASSERT(skb_headroom(userdata) >= LMP_HEADER+LMP_PID_HEADER,
            return -1;);

    /* Insert protocol identifier */
    skb_push(userdata, LMP_PID_HEADER);
    if(self != NULL)
      userdata->data[0] = self->pid;
    else
      userdata->data[0] = pid;

    /* Connectionless sockets must use 0x70 */
    skb_push(userdata, LMP_HEADER);
    userdata->data[0] = userdata->data[1] = LSAP_CONNLESS;

    /* Try to send Connectionless  packets out on all links */
    lap = (struct lap_cb *) hashbin_get_first(irlmp->links);
    while (lap != NULL) {
        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return -1;);

        clone_skb = skb_clone(userdata, GFP_ATOMIC);
        if (!clone_skb) {
            dev_kfree_skb(userdata);
            return -ENOMEM;
        }

        irlap_unitdata_request(lap->irlap, clone_skb);
        /* irlap_unitdata_request() don't increase refcount,
         * so no dev_kfree_skb() - Jean II */

        lap = (struct lap_cb *) hashbin_get_next(irlmp->links);
    }
    dev_kfree_skb(userdata);

    return 0;
}
#endif /* CONFIG_IRDA_ULTRA */

/*
 * Function irlmp_connless_data_indication (self, skb)
 *
 *    Receive unreliable data outside any connection. Mostly used by Ultra
 *
 */
#ifdef CONFIG_IRDA_ULTRA
void irlmp_connless_data_indication(struct lsap_cb *self, struct sk_buff *skb)
{
    IRDA_DEBUG(4, "%s()\n", __func__);

    IRDA_ASSERT(self != NULL, return;);
    IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;);
    IRDA_ASSERT(skb != NULL, return;);

    /* Hide LMP and PID header from layer above */
    skb_pull(skb, LMP_HEADER+LMP_PID_HEADER);

    if (self->notify.udata_indication) {
        /* Don't forget to refcount it - see irlap_driver_rcv(). */
        skb_get(skb);
        self->notify.udata_indication(self->notify.instance, self,
                          skb);
    }
}
#endif /* CONFIG_IRDA_ULTRA */

/*
 * Propagate status indication from LAP to LSAPs (via LMP)
 * This don't trigger any change of state in lap_cb, lmp_cb or lsap_cb,
 * and the event is stateless, therefore we can bypass both state machines
 * and send the event direct to the LSAP user.
 * Jean II
 */
void irlmp_status_indication(struct lap_cb *self,
                 LINK_STATUS link, LOCK_STATUS lock)
{
    struct lsap_cb *next;
    struct lsap_cb *curr;

    /* Send status_indication to all LSAPs using this link */
    curr = (struct lsap_cb *) hashbin_get_first( self->lsaps);
    while (NULL != hashbin_find_next(self->lsaps, (long) curr, NULL,
                     (void *) &next) ) {
        IRDA_ASSERT(curr->magic == LMP_LSAP_MAGIC, return;);
        /*
         *  Inform service user if he has requested it
         */
        if (curr->notify.status_indication != NULL)
            curr->notify.status_indication(curr->notify.instance,
                               link, lock);
        else
            IRDA_DEBUG(2, "%s(), no handler\n", __func__);

        curr = next;
    }
}

/*
 * Receive flow control indication from LAP.
 * LAP want us to send it one more frame. We implement a simple round
 * robin scheduler between the active sockets so that we get a bit of
 * fairness. Note that the round robin is far from perfect, but it's
 * better than nothing.
 * We then poll the selected socket so that we can do synchronous
 * refilling of IrLAP (which allow to minimise the number of buffers).
 * Jean II
 */
void irlmp_flow_indication(struct lap_cb *self, LOCAL_FLOW flow)
{
    struct lsap_cb *next;
    struct lsap_cb *curr;
    int lsap_todo;

    IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
    IRDA_ASSERT(flow == FLOW_START, return;);

    /* Get the number of lsap. That's the only safe way to know
     * that we have looped around... - Jean II */
    lsap_todo = HASHBIN_GET_SIZE(self->lsaps);
    IRDA_DEBUG(4, "%s() : %d lsaps to scan\n", __func__, lsap_todo);

    /* Poll lsap in order until the queue is full or until we
     * tried them all.
     * Most often, the current LSAP will have something to send,
     * so we will go through this loop only once. - Jean II */
    while((lsap_todo--) &&
          (IRLAP_GET_TX_QUEUE_LEN(self->irlap) < LAP_HIGH_THRESHOLD)) {
        /* Try to find the next lsap we should poll. */
        next = self->flow_next;
        /* If we have no lsap, restart from first one */
        if(next == NULL)
            next = (struct lsap_cb *) hashbin_get_first(self->lsaps);
        /* Verify current one and find the next one */
        curr = hashbin_find_next(self->lsaps, (long) next, NULL,
                     (void *) &self->flow_next);
        /* Uh-oh... Paranoia */
        if(curr == NULL)
            break;
        IRDA_DEBUG(4, "%s() : curr is %p, next was %p and is now %p, still %d to go - queue len = %d\n", __func__, curr, next, self->flow_next, lsap_todo, IRLAP_GET_TX_QUEUE_LEN(self->irlap));

        /* Inform lsap user that it can send one more packet. */
        if (curr->notify.flow_indication != NULL)
            curr->notify.flow_indication(curr->notify.instance,
                             curr, flow);
        else
            IRDA_DEBUG(1, "%s(), no handler\n", __func__);
    }
}

#if 0
/*
 * Function irlmp_hint_to_service (hint)
 *
 *    Returns a list of all servics contained in the given hint bits. This
 *    function assumes that the hint bits have the size of two bytes only
 */
__u8 *irlmp_hint_to_service(__u8 *hint)
{
    __u8 *service;
    int i = 0;

    /*
     * Allocate array to store services in. 16 entries should be safe
     * since we currently only support 2 hint bytes
     */
    service = kmalloc(16, GFP_ATOMIC);
    if (!service) {
        IRDA_DEBUG(1, "%s(), Unable to kmalloc!\n", __func__);
        return NULL;
    }

    if (!hint[0]) {
        IRDA_DEBUG(1, "<None>\n");
        kfree(service);
        return NULL;
    }
    if (hint[0] & HINT_PNP)
        IRDA_DEBUG(1, "PnP Compatible ");
    if (hint[0] & HINT_PDA)
        IRDA_DEBUG(1, "PDA/Palmtop ");
    if (hint[0] & HINT_COMPUTER)
        IRDA_DEBUG(1, "Computer ");
    if (hint[0] & HINT_PRINTER) {
        IRDA_DEBUG(1, "Printer ");
        service[i++] = S_PRINTER;
    }
    if (hint[0] & HINT_MODEM)
        IRDA_DEBUG(1, "Modem ");
    if (hint[0] & HINT_FAX)
        IRDA_DEBUG(1, "Fax ");
    if (hint[0] & HINT_LAN) {
        IRDA_DEBUG(1, "LAN Access ");
        service[i++] = S_LAN;
    }
    /*
     *  Test if extension byte exists. This byte will usually be
     *  there, but this is not really required by the standard.
     *  (IrLMP p. 29)
     */
    if (hint[0] & HINT_EXTENSION) {
        if (hint[1] & HINT_TELEPHONY) {
            IRDA_DEBUG(1, "Telephony ");
            service[i++] = S_TELEPHONY;
        } if (hint[1] & HINT_FILE_SERVER)
            IRDA_DEBUG(1, "File Server ");

        if (hint[1] & HINT_COMM) {
            IRDA_DEBUG(1, "IrCOMM ");
            service[i++] = S_COMM;
        }
        if (hint[1] & HINT_OBEX) {
            IRDA_DEBUG(1, "IrOBEX ");
            service[i++] = S_OBEX;
        }
    }
    IRDA_DEBUG(1, "\n");

    /* So that client can be notified about any discovery */
    service[i++] = S_ANY;

    service[i] = S_END;

    return service;
}
#endif

static const __u16 service_hint_mapping[S_END][2] = {
    { HINT_PNP,     0 },            /* S_PNP */
    { HINT_PDA,     0 },            /* S_PDA */
    { HINT_COMPUTER,    0 },            /* S_COMPUTER */
    { HINT_PRINTER,     0 },            /* S_PRINTER */
    { HINT_MODEM,       0 },            /* S_MODEM */
    { HINT_FAX,     0 },            /* S_FAX */
    { HINT_LAN,     0 },            /* S_LAN */
    { HINT_EXTENSION,   HINT_TELEPHONY },   /* S_TELEPHONY */
    { HINT_EXTENSION,   HINT_COMM },        /* S_COMM */
    { HINT_EXTENSION,   HINT_OBEX },        /* S_OBEX */
    { 0xFF,         0xFF },         /* S_ANY */
};

/*
 * Function irlmp_service_to_hint (service)
 *
 *    Converts a service type, to a hint bit
 *
 *    Returns: a 16 bit hint value, with the service bit set
 */
__u16 irlmp_service_to_hint(int service)
{
    __u16_host_order hint;

    hint.byte[0] = service_hint_mapping[service][0];
    hint.byte[1] = service_hint_mapping[service][1];

    return hint.word;
}
EXPORT_SYMBOL(irlmp_service_to_hint);

/*
 * Function irlmp_register_service (service)
 *
 *    Register local service with IrLMP
 *
 */
void *irlmp_register_service(__u16 hints)
{
    irlmp_service_t *service;

    IRDA_DEBUG(4, "%s(), hints = %04x\n", __func__, hints);

    /* Make a new registration */
    service = kmalloc(sizeof(irlmp_service_t), GFP_ATOMIC);
    if (!service) {
        IRDA_DEBUG(1, "%s(), Unable to kmalloc!\n", __func__);
        return NULL;
    }
    service->hints.word = hints;
    hashbin_insert(irlmp->services, (irda_queue_t *) service,
               (long) service, NULL);

    irlmp->hints.word |= hints;

    return (void *)service;
}
EXPORT_SYMBOL(irlmp_register_service);

/*
 * Function irlmp_unregister_service (handle)
 *
 *    Unregister service with IrLMP.
 *
 *    Returns: 0 on success, -1 on error
 */
int irlmp_unregister_service(void *handle)
{
    irlmp_service_t *service;
    unsigned long flags;

    IRDA_DEBUG(4, "%s()\n", __func__);

    if (!handle)
        return -1;

    /* Caller may call with invalid handle (it's legal) - Jean II */
    service = hashbin_lock_find(irlmp->services, (long) handle, NULL);
    if (!service) {
        IRDA_DEBUG(1, "%s(), Unknown service!\n", __func__);
        return -1;
    }

    hashbin_remove_this(irlmp->services, (irda_queue_t *) service);
    kfree(service);

    /* Remove old hint bits */
    irlmp->hints.word = 0;

    /* Refresh current hint bits */
    spin_lock_irqsave(&irlmp->services->hb_spinlock, flags);
    service = (irlmp_service_t *) hashbin_get_first(irlmp->services);
    while (service) {
        irlmp->hints.word |= service->hints.word;

        service = (irlmp_service_t *)hashbin_get_next(irlmp->services);
    }
    spin_unlock_irqrestore(&irlmp->services->hb_spinlock, flags);
    return 0;
}
EXPORT_SYMBOL(irlmp_unregister_service);

/*
 * Function irlmp_register_client (hint_mask, callback1, callback2)
 *
 *    Register a local client with IrLMP
 *  First callback is selective discovery (based on hints)
 *  Second callback is for selective discovery expiries
 *
 *    Returns: handle > 0 on success, 0 on error
 */
void *irlmp_register_client(__u16 hint_mask, DISCOVERY_CALLBACK1 disco_clb,
                DISCOVERY_CALLBACK2 expir_clb, void *priv)
{
    irlmp_client_t *client;

    IRDA_DEBUG(1, "%s()\n", __func__);
    IRDA_ASSERT(irlmp != NULL, return NULL;);

    /* Make a new registration */
    client = kmalloc(sizeof(irlmp_client_t), GFP_ATOMIC);
    if (!client) {
        IRDA_DEBUG( 1, "%s(), Unable to kmalloc!\n", __func__);
        return NULL;
    }

    /* Register the details */
    client->hint_mask.word = hint_mask;
    client->disco_callback = disco_clb;
    client->expir_callback = expir_clb;
    client->priv = priv;

    hashbin_insert(irlmp->clients, (irda_queue_t *) client,
               (long) client, NULL);

    return (void *) client;
}
EXPORT_SYMBOL(irlmp_register_client);

/*
 * Function irlmp_update_client (handle, hint_mask, callback1, callback2)
 *
 *    Updates specified client (handle) with possibly new hint_mask and
 *    callback
 *
 *    Returns: 0 on success, -1 on error
 */
int irlmp_update_client(void *handle, __u16 hint_mask,
            DISCOVERY_CALLBACK1 disco_clb,
            DISCOVERY_CALLBACK2 expir_clb, void *priv)
{
    irlmp_client_t *client;

    if (!handle)
        return -1;

    client = hashbin_lock_find(irlmp->clients, (long) handle, NULL);
    if (!client) {
        IRDA_DEBUG(1, "%s(), Unknown client!\n", __func__);
        return -1;
    }

    client->hint_mask.word = hint_mask;
    client->disco_callback = disco_clb;
    client->expir_callback = expir_clb;
    client->priv = priv;

    return 0;
}
EXPORT_SYMBOL(irlmp_update_client);

/*
 * Function irlmp_unregister_client (handle)
 *
 *    Returns: 0 on success, -1 on error
 *
 */
int irlmp_unregister_client(void *handle)
{
    struct irlmp_client *client;

    IRDA_DEBUG(4, "%s()\n", __func__);

    if (!handle)
        return -1;

    /* Caller may call with invalid handle (it's legal) - Jean II */
    client = hashbin_lock_find(irlmp->clients, (long) handle, NULL);
    if (!client) {
        IRDA_DEBUG(1, "%s(), Unknown client!\n", __func__);
        return -1;
    }

    IRDA_DEBUG(4, "%s(), removing client!\n", __func__);
    hashbin_remove_this(irlmp->clients, (irda_queue_t *) client);
    kfree(client);

    return 0;
}
EXPORT_SYMBOL(irlmp_unregister_client);

/*
 * Function irlmp_slsap_inuse (slsap)
 *
 *    Check if the given source LSAP selector is in use
 *
 * This function is clearly not very efficient. On the mitigating side, the
 * stack make sure that in 99% of the cases, we are called only once
 * for each socket allocation. We could probably keep a bitmap
 * of the allocated LSAP, but I'm not sure the complexity is worth it.
 * Jean II
 */
static int irlmp_slsap_inuse(__u8 slsap_sel)
{
    struct lsap_cb *self;
    struct lap_cb *lap;
    unsigned long flags;

    IRDA_ASSERT(irlmp != NULL, return TRUE;);
    IRDA_ASSERT(irlmp->magic == LMP_MAGIC, return TRUE;);
    IRDA_ASSERT(slsap_sel != LSAP_ANY, return TRUE;);

    IRDA_DEBUG(4, "%s()\n", __func__);

#ifdef CONFIG_IRDA_ULTRA
    /* Accept all bindings to the connectionless LSAP */
    if (slsap_sel == LSAP_CONNLESS)
        return FALSE;
#endif /* CONFIG_IRDA_ULTRA */

    /* Valid values are between 0 and 127 (0x0-0x6F) */
    if (slsap_sel > LSAP_MAX)
        return TRUE;

    /*
     *  Check if slsap is already in use. To do this we have to loop over
     *  every IrLAP connection and check every LSAP associated with each
     *  the connection.
     */
    spin_lock_irqsave_nested(&irlmp->links->hb_spinlock, flags,
            SINGLE_DEPTH_NESTING);
    lap = (struct lap_cb *) hashbin_get_first(irlmp->links);
    while (lap != NULL) {
        IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, goto errlap;);

        /* Careful for priority inversions here !
         * irlmp->links is never taken while another IrDA
         * spinlock is held, so we are safe. Jean II */
        spin_lock(&lap->lsaps->hb_spinlock);

        /* For this IrLAP, check all the LSAPs */
        self = (struct lsap_cb *) hashbin_get_first(lap->lsaps);
        while (self != NULL) {
            IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC,
                    goto errlsap;);

            if ((self->slsap_sel == slsap_sel)) {
                IRDA_DEBUG(4, "Source LSAP selector=%02x in use\n",
                       self->slsap_sel);
                goto errlsap;
            }
            self = (struct lsap_cb*) hashbin_get_next(lap->lsaps);
        }
        spin_unlock(&lap->lsaps->hb_spinlock);

        /* Next LAP */
        lap = (struct lap_cb *) hashbin_get_next(irlmp->links);
    }
    spin_unlock_irqrestore(&irlmp->links->hb_spinlock, flags);

    /*
     * Server sockets are typically waiting for connections and
     * therefore reside in the unconnected list. We don't want
     * to give out their LSAPs for obvious reasons...
     * Jean II
     */
    spin_lock_irqsave(&irlmp->unconnected_lsaps->hb_spinlock, flags);

    self = (struct lsap_cb *) hashbin_get_first(irlmp->unconnected_lsaps);
    while (self != NULL) {
        IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, goto erruncon;);
        if ((self->slsap_sel == slsap_sel)) {
            IRDA_DEBUG(4, "Source LSAP selector=%02x in use (unconnected)\n",
                   self->slsap_sel);
            goto erruncon;
        }
        self = (struct lsap_cb*) hashbin_get_next(irlmp->unconnected_lsaps);
    }
    spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);

    return FALSE;

    /* Error exit from within one of the two nested loops.
     * Make sure we release the right spinlock in the righ order.
     * Jean II */
errlsap:
    spin_unlock(&lap->lsaps->hb_spinlock);
IRDA_ASSERT_LABEL(errlap:)
    spin_unlock_irqrestore(&irlmp->links->hb_spinlock, flags);
    return TRUE;

    /* Error exit from within the unconnected loop.
     * Just one spinlock to release... Jean II */
erruncon:
    spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);
    return TRUE;
}

/*
 * Function irlmp_find_free_slsap ()
 *
 *    Find a free source LSAP to use. This function is called if the service
 *    user has requested a source LSAP equal to LM_ANY
 */
static __u8 irlmp_find_free_slsap(void)
{
    __u8 lsap_sel;
    int wrapped = 0;

    IRDA_ASSERT(irlmp != NULL, return -1;);
    IRDA_ASSERT(irlmp->magic == LMP_MAGIC, return -1;);

    /* Most users don't really care which LSAPs they are given,
     * and therefore we automatically give them a free LSAP.
     * This function try to find a suitable LSAP, i.e. which is
     * not in use and is within the acceptable range. Jean II */

    do {
        /* Always increment to LSAP number before using it.
         * In theory, we could reuse the last LSAP number, as long
         * as it is no longer in use. Some IrDA stack do that.
         * However, the previous socket may be half closed, i.e.
         * we closed it, we think it's no longer in use, but the
         * other side did not receive our close and think it's
         * active and still send data on it.
         * This is similar to what is done with PIDs and TCP ports.
         * Also, this reduce the number of calls to irlmp_slsap_inuse()
         * which is an expensive function to call.
         * Jean II */
        irlmp->last_lsap_sel++;

        /* Check if we need to wraparound (0x70-0x7f are reserved) */
        if (irlmp->last_lsap_sel > LSAP_MAX) {
            /* 0x00-0x10 are also reserved for well know ports */
            irlmp->last_lsap_sel = 0x10;

            /* Make sure we terminate the loop */
            if (wrapped++) {
                IRDA_ERROR("%s: no more free LSAPs !\n",
                       __func__);
                return 0;
            }
        }

        /* If the LSAP is in use, try the next one.
         * Despite the autoincrement, we need to check if the lsap
         * is really in use or not, first because LSAP may be
         * directly allocated in irlmp_open_lsap(), and also because
         * we may wraparound on old sockets. Jean II */
    } while (irlmp_slsap_inuse(irlmp->last_lsap_sel));

    /* Got it ! */
    lsap_sel = irlmp->last_lsap_sel;
    IRDA_DEBUG(4, "%s(), found free lsap_sel=%02x\n",
           __func__, lsap_sel);

    return lsap_sel;
}

/*
 * Function irlmp_convert_lap_reason (lap_reason)
 *
 *    Converts IrLAP disconnect reason codes to IrLMP disconnect reason
 *    codes
 *
 */
LM_REASON irlmp_convert_lap_reason( LAP_REASON lap_reason)
{
    int reason = LM_LAP_DISCONNECT;

    switch (lap_reason) {
    case LAP_DISC_INDICATION: /* Received a disconnect request from peer */
        IRDA_DEBUG( 1, "%s(), LAP_DISC_INDICATION\n", __func__);
        reason = LM_USER_REQUEST;
        break;
    case LAP_NO_RESPONSE:    /* To many retransmits without response */
        IRDA_DEBUG( 1, "%s(), LAP_NO_RESPONSE\n", __func__);
        reason = LM_LAP_DISCONNECT;
        break;
    case LAP_RESET_INDICATION:
        IRDA_DEBUG( 1, "%s(), LAP_RESET_INDICATION\n", __func__);
        reason = LM_LAP_RESET;
        break;
    case LAP_FOUND_NONE:
    case LAP_MEDIA_BUSY:
    case LAP_PRIMARY_CONFLICT:
        IRDA_DEBUG(1, "%s(), LAP_FOUND_NONE, LAP_MEDIA_BUSY or LAP_PRIMARY_CONFLICT\n", __func__);
        reason = LM_CONNECT_FAILURE;
        break;
    default:
        IRDA_DEBUG(1, "%s(), Unknown IrLAP disconnect reason %d!\n",
               __func__, lap_reason);
        reason = LM_LAP_DISCONNECT;
        break;
    }

    return reason;
}

#ifdef CONFIG_PROC_FS

struct irlmp_iter_state {
    hashbin_t *hashbin;
};

#define LSAP_START_TOKEN    ((void *)1)
#define LINK_START_TOKEN    ((void *)2)

static void *irlmp_seq_hb_idx(struct irlmp_iter_state *iter, loff_t *off)
{
    void *element;

    spin_lock_irq(&iter->hashbin->hb_spinlock);
    for (element = hashbin_get_first(iter->hashbin);
         element != NULL;
         element = hashbin_get_next(iter->hashbin)) {
        if (!off || *off-- == 0) {
            /* NB: hashbin left locked */
            return element;
        }
    }
    spin_unlock_irq(&iter->hashbin->hb_spinlock);
    iter->hashbin = NULL;
    return NULL;
}


static void *irlmp_seq_start(struct seq_file *seq, loff_t *pos)
{
    struct irlmp_iter_state *iter = seq->private;
    void *v;
    loff_t off = *pos;

    iter->hashbin = NULL;
    if (off-- == 0)
        return LSAP_START_TOKEN;

    iter->hashbin = irlmp->unconnected_lsaps;
    v = irlmp_seq_hb_idx(iter, &off);
    if (v)
        return v;

    if (off-- == 0)
        return LINK_START_TOKEN;

    iter->hashbin = irlmp->links;
    return irlmp_seq_hb_idx(iter, &off);
}

static void *irlmp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
    struct irlmp_iter_state *iter = seq->private;

    ++*pos;

    if (v == LSAP_START_TOKEN) {        /* start of list of lsaps */
        iter->hashbin = irlmp->unconnected_lsaps;
        v = irlmp_seq_hb_idx(iter, NULL);
        return v ? v : LINK_START_TOKEN;
    }

    if (v == LINK_START_TOKEN) {        /* start of list of links */
        iter->hashbin = irlmp->links;
        return irlmp_seq_hb_idx(iter, NULL);
    }

    v = hashbin_get_next(iter->hashbin);

    if (v == NULL) {            /* no more in this hash bin */
        spin_unlock_irq(&iter->hashbin->hb_spinlock);

        if (iter->hashbin == irlmp->unconnected_lsaps)
            v =  LINK_START_TOKEN;

        iter->hashbin = NULL;
    }
    return v;
}

static void irlmp_seq_stop(struct seq_file *seq, void *v)
{
    struct irlmp_iter_state *iter = seq->private;

    if (iter->hashbin)
        spin_unlock_irq(&iter->hashbin->hb_spinlock);
}

static int irlmp_seq_show(struct seq_file *seq, void *v)
{
    const struct irlmp_iter_state *iter = seq->private;
    struct lsap_cb *self = v;

    if (v == LSAP_START_TOKEN)
        seq_puts(seq, "Unconnected LSAPs:\n");
    else if (v == LINK_START_TOKEN)
        seq_puts(seq, "\nRegistered Link Layers:\n");
    else if (iter->hashbin == irlmp->unconnected_lsaps) {
        self = v;
        IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return -EINVAL; );
        seq_printf(seq, "lsap state: %s, ",
               irlsap_state[ self->lsap_state]);
        seq_printf(seq,
               "slsap_sel: %#02x, dlsap_sel: %#02x, ",
               self->slsap_sel, self->dlsap_sel);
        seq_printf(seq, "(%s)", self->notify.name);
        seq_printf(seq, "\n");
    } else if (iter->hashbin == irlmp->links) {
        struct lap_cb *lap = v;

        seq_printf(seq, "lap state: %s, ",
               irlmp_state[lap->lap_state]);

        seq_printf(seq, "saddr: %#08x, daddr: %#08x, ",
               lap->saddr, lap->daddr);
        seq_printf(seq, "num lsaps: %d",
               HASHBIN_GET_SIZE(lap->lsaps));
        seq_printf(seq, "\n");

        /* Careful for priority inversions here !
         * All other uses of attrib spinlock are independent of
         * the object spinlock, so we are safe. Jean II */
        spin_lock(&lap->lsaps->hb_spinlock);

        seq_printf(seq, "\n  Connected LSAPs:\n");
        for (self = (struct lsap_cb *) hashbin_get_first(lap->lsaps);
             self != NULL;
             self = (struct lsap_cb *)hashbin_get_next(lap->lsaps)) {
            IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC,
                    goto outloop;);
            seq_printf(seq, "  lsap state: %s, ",
                   irlsap_state[ self->lsap_state]);
            seq_printf(seq,
                   "slsap_sel: %#02x, dlsap_sel: %#02x, ",
                   self->slsap_sel, self->dlsap_sel);
            seq_printf(seq, "(%s)", self->notify.name);
            seq_putc(seq, '\n');

        }
    IRDA_ASSERT_LABEL(outloop:)
        spin_unlock(&lap->lsaps->hb_spinlock);
        seq_putc(seq, '\n');
    } else
        return -EINVAL;

    return 0;
}

static const struct seq_operations irlmp_seq_ops = {
    .start  = irlmp_seq_start,
    .next   = irlmp_seq_next,
    .stop   = irlmp_seq_stop,
    .show   = irlmp_seq_show,
};

static int irlmp_seq_open(struct inode *inode, struct file *file)
{
    IRDA_ASSERT(irlmp != NULL, return -EINVAL;);

    return seq_open_private(file, &irlmp_seq_ops,
            sizeof(struct irlmp_iter_state));
}

const struct file_operations irlmp_seq_fops = {
    .owner      = THIS_MODULE,
    .open           = irlmp_seq_open,
    .read           = seq_read,
    .llseek         = seq_lseek,
    .release    = seq_release_private,
};

#endif /* PROC_FS */