ozproto.c

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/* -----------------------------------------------------------------------------
 * Copyright (c) 2011 Ozmo Inc
 * Released under the GNU General Public License Version 2 (GPLv2).
 * -----------------------------------------------------------------------------
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/timer.h>
#include <linux/sched.h>
#include <linux/netdevice.h>
#include <linux/errno.h>
#include <linux/ieee80211.h>
#include "ozconfig.h"
#include "ozprotocol.h"
#include "ozeltbuf.h"
#include "ozpd.h"
#include "ozproto.h"
#include "ozusbsvc.h"
#include "oztrace.h"
#include "ozappif.h"
#include "ozevent.h"
#include <asm/unaligned.h>
#include <linux/uaccess.h>
#include <net/psnap.h>
/*------------------------------------------------------------------------------
 */
#define OZ_CF_CONN_SUCCESS  1
#define OZ_CF_CONN_FAILURE  2

#define OZ_DO_STOP      1
#define OZ_DO_SLEEP     2

/* States of the timer.
 */
#define OZ_TIMER_IDLE       0
#define OZ_TIMER_SET        1
#define OZ_TIMER_IN_HANDLER 2

#define OZ_MAX_TIMER_POOL_SIZE  16

/*------------------------------------------------------------------------------
 */
struct oz_binding {
    struct packet_type ptype;
    char name[OZ_MAX_BINDING_LEN];
    struct oz_binding *next;
};

struct oz_timer {
    struct list_head link;
    struct oz_pd *pd;
    unsigned long due_time;
    int type;
};
/*------------------------------------------------------------------------------
 * Static external variables.
 */
static DEFINE_SPINLOCK(g_polling_lock);
static LIST_HEAD(g_pd_list);
static struct oz_binding *g_binding ;
static DEFINE_SPINLOCK(g_binding_lock);
static struct sk_buff_head g_rx_queue;
static u8 g_session_id;
static u16 g_apps = 0x1;
static int g_processing_rx;
static struct timer_list g_timer;
static struct oz_timer *g_cur_timer;
static struct list_head *g_timer_pool;
static int g_timer_pool_count;
static int g_timer_state = OZ_TIMER_IDLE;
static LIST_HEAD(g_timer_list);
/*------------------------------------------------------------------------------
 */
static void oz_protocol_timer_start(void);
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static u8 oz_get_new_session_id(u8 exclude)
{
    if (++g_session_id == 0)
        g_session_id = 1;
    if (g_session_id == exclude) {
        if (++g_session_id == 0)
            g_session_id = 1;
    }
    return g_session_id;
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static void oz_send_conn_rsp(struct oz_pd *pd, u8 status)
{
    struct sk_buff *skb;
    struct net_device *dev = pd->net_dev;
    struct oz_hdr *oz_hdr;
    struct oz_elt *elt;
    struct oz_elt_connect_rsp *body;
    int sz = sizeof(struct oz_hdr) + sizeof(struct oz_elt) +
            sizeof(struct oz_elt_connect_rsp);
    skb = alloc_skb(sz + OZ_ALLOCATED_SPACE(dev), GFP_ATOMIC);
    if (skb == 0)
        return;
    skb_reserve(skb, LL_RESERVED_SPACE(dev));
    skb_reset_network_header(skb);
    oz_hdr = (struct oz_hdr *)skb_put(skb, sz);
    elt = (struct oz_elt *)(oz_hdr+1);
    body = (struct oz_elt_connect_rsp *)(elt+1);
    skb->dev = dev;
    skb->protocol = htons(OZ_ETHERTYPE);
    /* Fill in device header */
    if (dev_hard_header(skb, dev, OZ_ETHERTYPE, pd->mac_addr,
            dev->dev_addr, skb->len) < 0) {
        kfree_skb(skb);
        return;
    }
    oz_hdr->control = (OZ_PROTOCOL_VERSION<<OZ_VERSION_SHIFT);
    oz_hdr->last_pkt_num = 0;
    put_unaligned(0, &oz_hdr->pkt_num);
    oz_event_log(OZ_EVT_CONNECT_RSP, 0, 0, 0, 0);
    elt->type = OZ_ELT_CONNECT_RSP;
    elt->length = sizeof(struct oz_elt_connect_rsp);
    memset(body, 0, sizeof(struct oz_elt_connect_rsp));
    body->status = status;
    if (status == 0) {
        body->mode = pd->mode;
        body->session_id = pd->session_id;
        put_unaligned(cpu_to_le16(pd->total_apps), &body->apps);
    }
    oz_trace("TX: OZ_ELT_CONNECT_RSP %d", status);
    dev_queue_xmit(skb);
    return;
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static void pd_set_keepalive(struct oz_pd *pd, u8 kalive)
{
    unsigned long keep_alive = kalive & OZ_KALIVE_VALUE_MASK;

    switch (kalive & OZ_KALIVE_TYPE_MASK) {
    case OZ_KALIVE_SPECIAL:
        pd->keep_alive_j =
            oz_ms_to_jiffies(keep_alive * 1000*60*60*24*20);
        break;
    case OZ_KALIVE_SECS:
        pd->keep_alive_j = oz_ms_to_jiffies(keep_alive*1000);
        break;
    case OZ_KALIVE_MINS:
        pd->keep_alive_j = oz_ms_to_jiffies(keep_alive*1000*60);
        break;
    case OZ_KALIVE_HOURS:
        pd->keep_alive_j = oz_ms_to_jiffies(keep_alive*1000*60*60);
        break;
    default:
        pd->keep_alive_j = 0;
    }
    oz_trace("Keepalive = %lu jiffies\n", pd->keep_alive_j);
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static void pd_set_presleep(struct oz_pd *pd, u8 presleep)
{
    if (presleep)
        pd->presleep_j = oz_ms_to_jiffies(presleep*100);
    else
        pd->presleep_j = OZ_PRESLEEP_TOUT_J;
    oz_trace("Presleep time = %lu jiffies\n", pd->presleep_j);
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static struct oz_pd *oz_connect_req(struct oz_pd *cur_pd, struct oz_elt *elt,
            u8 *pd_addr, struct net_device *net_dev)
{
    struct oz_pd *pd;
    struct oz_elt_connect_req *body =
            (struct oz_elt_connect_req *)(elt+1);
    u8 rsp_status = OZ_STATUS_SUCCESS;
    u8 stop_needed = 0;
    u16 new_apps = g_apps;
    struct net_device *old_net_dev = 0;
    struct oz_pd *free_pd = 0;
    if (cur_pd) {
        pd = cur_pd;
        spin_lock_bh(&g_polling_lock);
    } else {
        struct oz_pd *pd2 = 0;
        struct list_head *e;
        pd = oz_pd_alloc(pd_addr);
        if (pd == 0)
            return 0;
        pd->last_rx_time_j = jiffies;
        spin_lock_bh(&g_polling_lock);
        list_for_each(e, &g_pd_list) {
            pd2 = container_of(e, struct oz_pd, link);
            if (memcmp(pd2->mac_addr, pd_addr, ETH_ALEN) == 0) {
                free_pd = pd;
                pd = pd2;
                break;
            }
        }
        if (pd != pd2)
            list_add_tail(&pd->link, &g_pd_list);
    }
    if (pd == 0) {
        spin_unlock_bh(&g_polling_lock);
        return 0;
    }
    if (pd->net_dev != net_dev) {
        old_net_dev = pd->net_dev;
        dev_hold(net_dev);
        pd->net_dev = net_dev;
    }
    oz_trace("Host vendor: %d\n", body->host_vendor);
    pd->max_tx_size = OZ_MAX_TX_SIZE;
    pd->mode = body->mode;
    pd->pd_info = body->pd_info;
    if (pd->mode & OZ_F_ISOC_NO_ELTS) {
        pd->ms_per_isoc = body->ms_per_isoc;
        if (!pd->ms_per_isoc)
            pd->ms_per_isoc = 4;

        switch (body->ms_isoc_latency & OZ_LATENCY_MASK) {
        case OZ_ONE_MS_LATENCY:
            pd->isoc_latency = (body->ms_isoc_latency &
                    ~OZ_LATENCY_MASK) / pd->ms_per_isoc;
            break;
        case OZ_TEN_MS_LATENCY:
            pd->isoc_latency = ((body->ms_isoc_latency &
                ~OZ_LATENCY_MASK) * 10) / pd->ms_per_isoc;
            break;
        default:
            pd->isoc_latency = OZ_MAX_TX_QUEUE_ISOC;
        }
    }
    if (body->max_len_div16)
        pd->max_tx_size = ((u16)body->max_len_div16)<<4;
    oz_trace("Max frame:%u Ms per isoc:%u\n",
        pd->max_tx_size, pd->ms_per_isoc);
    pd->max_stream_buffering = 3*1024;
    pd->timeout_time_j = jiffies + OZ_CONNECTION_TOUT_J;
    pd->pulse_period_j = OZ_QUANTUM_J;
    pd_set_presleep(pd, body->presleep);
    pd_set_keepalive(pd, body->keep_alive);

    new_apps &= le16_to_cpu(get_unaligned(&body->apps));
    if ((new_apps & 0x1) && (body->session_id)) {
        if (pd->session_id) {
            if (pd->session_id != body->session_id) {
                rsp_status = OZ_STATUS_SESSION_MISMATCH;
                goto done;
            }
        } else {
            new_apps &= ~0x1;  /* Resume not permitted */
            pd->session_id =
                oz_get_new_session_id(body->session_id);
        }
    } else {
        if (pd->session_id && !body->session_id) {
            rsp_status = OZ_STATUS_SESSION_TEARDOWN;
            stop_needed = 1;
        } else {
            new_apps &= ~0x1;  /* Resume not permitted */
            pd->session_id =
                oz_get_new_session_id(body->session_id);
        }
    }
done:
    if (rsp_status == OZ_STATUS_SUCCESS) {
        u16 start_apps = new_apps & ~pd->total_apps & ~0x1;
        u16 stop_apps = pd->total_apps & ~new_apps & ~0x1;
        u16 resume_apps = new_apps & pd->paused_apps  & ~0x1;
        spin_unlock_bh(&g_polling_lock);
        oz_pd_set_state(pd, OZ_PD_S_CONNECTED);
        oz_timer_delete(pd, OZ_TIMER_STOP);
        oz_trace("new_apps=0x%x total_apps=0x%x paused_apps=0x%x\n",
            new_apps, pd->total_apps, pd->paused_apps);
        if (start_apps) {
            if (oz_services_start(pd, start_apps, 0))
                rsp_status = OZ_STATUS_TOO_MANY_PDS;
        }
        if (resume_apps)
            if (oz_services_start(pd, resume_apps, 1))
                rsp_status = OZ_STATUS_TOO_MANY_PDS;
        if (stop_apps)
            oz_services_stop(pd, stop_apps, 0);
        oz_pd_request_heartbeat(pd);
    } else {
        spin_unlock_bh(&g_polling_lock);
    }
    oz_send_conn_rsp(pd, rsp_status);
    if (rsp_status != OZ_STATUS_SUCCESS) {
        if (stop_needed)
            oz_pd_stop(pd);
        oz_pd_put(pd);
        pd = 0;
    }
    if (old_net_dev)
        dev_put(old_net_dev);
    if (free_pd)
        oz_pd_destroy(free_pd);
    return pd;
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static void oz_add_farewell(struct oz_pd *pd, u8 ep_num, u8 index,
            u8 *report, u8 len)
{
    struct oz_farewell *f;
    struct oz_farewell *f2;
    int found = 0;
    f = kmalloc(sizeof(struct oz_farewell) + len - 1, GFP_ATOMIC);
    if (!f)
        return;
    f->ep_num = ep_num;
    f->index = index;
    memcpy(f->report, report, len);
    oz_trace("RX: Adding farewell report\n");
    spin_lock(&g_polling_lock);
    list_for_each_entry(f2, &pd->farewell_list, link) {
        if ((f2->ep_num == ep_num) && (f2->index == index)) {
            found = 1;
            list_del(&f2->link);
            break;
        }
    }
    list_add_tail(&f->link, &pd->farewell_list);
    spin_unlock(&g_polling_lock);
    if (found)
        kfree(f2);
}
/*------------------------------------------------------------------------------
 * Context: softirq-serialized
 */
static void oz_rx_frame(struct sk_buff *skb)
{
    u8 *mac_hdr;
    u8 *src_addr;
    struct oz_elt *elt;
    int length;
    struct oz_pd *pd = 0;
    struct oz_hdr *oz_hdr = (struct oz_hdr *)skb_network_header(skb);
    int dup = 0;
    u32 pkt_num;

    oz_event_log(OZ_EVT_RX_PROCESS, 0,
        (((u16)oz_hdr->control)<<8)|oz_hdr->last_pkt_num,
        0, oz_hdr->pkt_num);
    oz_trace2(OZ_TRACE_RX_FRAMES,
        "RX frame PN=0x%x LPN=0x%x control=0x%x\n",
        oz_hdr->pkt_num, oz_hdr->last_pkt_num, oz_hdr->control);
    mac_hdr = skb_mac_header(skb);
    src_addr = &mac_hdr[ETH_ALEN] ;
    length = skb->len;

    /* Check the version field */
    if (oz_get_prot_ver(oz_hdr->control) != OZ_PROTOCOL_VERSION) {
        oz_trace("Incorrect protocol version: %d\n",
            oz_get_prot_ver(oz_hdr->control));
        goto done;
    }

    pkt_num = le32_to_cpu(get_unaligned(&oz_hdr->pkt_num));

    pd = oz_pd_find(src_addr);
    if (pd) {
        pd->last_rx_time_j = jiffies;
        oz_timer_add(pd, OZ_TIMER_TOUT,
            pd->last_rx_time_j + pd->presleep_j, 1);
        if (pkt_num != pd->last_rx_pkt_num) {
            pd->last_rx_pkt_num = pkt_num;
        } else {
            dup = 1;
            oz_trace("Duplicate frame\n");
        }
    }

    if (pd && !dup && ((pd->mode & OZ_MODE_MASK) == OZ_MODE_TRIGGERED)) {
        oz_trace2(OZ_TRACE_RX_FRAMES, "Received TRIGGER Frame\n");
        pd->last_sent_frame = &pd->tx_queue;
        if (oz_hdr->control & OZ_F_ACK) {
            /* Retire completed frames */
            oz_retire_tx_frames(pd, oz_hdr->last_pkt_num);
        }
        if ((oz_hdr->control & OZ_F_ACK_REQUESTED) &&
                (pd->state == OZ_PD_S_CONNECTED)) {
            int backlog = pd->nb_queued_frames;
            pd->trigger_pkt_num = pkt_num;
            /* Send queued frames */
            oz_send_queued_frames(pd, backlog);
        }
    }

    length -= sizeof(struct oz_hdr);
    elt = (struct oz_elt *)((u8 *)oz_hdr + sizeof(struct oz_hdr));

    while (length >= sizeof(struct oz_elt)) {
        length -= sizeof(struct oz_elt) + elt->length;
        if (length < 0)
            break;
        switch (elt->type) {
        case OZ_ELT_CONNECT_REQ:
            oz_event_log(OZ_EVT_CONNECT_REQ, 0, 0, 0, 0);
            oz_trace("RX: OZ_ELT_CONNECT_REQ\n");
            pd = oz_connect_req(pd, elt, src_addr, skb->dev);
            break;
        case OZ_ELT_DISCONNECT:
            oz_trace("RX: OZ_ELT_DISCONNECT\n");
            if (pd)
                oz_pd_sleep(pd);
            break;
        case OZ_ELT_UPDATE_PARAM_REQ: {
                struct oz_elt_update_param *body =
                    (struct oz_elt_update_param *)(elt + 1);
                oz_trace("RX: OZ_ELT_UPDATE_PARAM_REQ\n");
                if (pd && (pd->state & OZ_PD_S_CONNECTED)) {
                    spin_lock(&g_polling_lock);
                    pd_set_keepalive(pd, body->keepalive);
                    pd_set_presleep(pd, body->presleep);
                    spin_unlock(&g_polling_lock);
                }
            }
            break;
        case OZ_ELT_FAREWELL_REQ: {
                struct oz_elt_farewell *body =
                    (struct oz_elt_farewell *)(elt + 1);
                oz_trace("RX: OZ_ELT_FAREWELL_REQ\n");
                oz_add_farewell(pd, body->ep_num,
                    body->index, body->report,
                    elt->length + 1 - sizeof(*body));
            }
            break;
        case OZ_ELT_APP_DATA:
            if (pd && (pd->state & OZ_PD_S_CONNECTED)) {
                struct oz_app_hdr *app_hdr =
                    (struct oz_app_hdr *)(elt+1);
                if (dup)
                    break;
                oz_handle_app_elt(pd, app_hdr->app_id, elt);
            }
            break;
        default:
            oz_trace("RX: Unknown elt %02x\n", elt->type);
        }
        elt = oz_next_elt(elt);
    }
done:
    if (pd)
        oz_pd_put(pd);
    consume_skb(skb);
}
/*------------------------------------------------------------------------------
 * Context: process
 */
void oz_protocol_term(void)
{
    struct list_head *chain = 0;
    del_timer_sync(&g_timer);
    /* Walk the list of bindings and remove each one.
     */
    spin_lock_bh(&g_binding_lock);
    while (g_binding) {
        struct oz_binding *b = g_binding;
        g_binding = b->next;
        spin_unlock_bh(&g_binding_lock);
        dev_remove_pack(&b->ptype);
        if (b->ptype.dev)
            dev_put(b->ptype.dev);
        kfree(b);
        spin_lock_bh(&g_binding_lock);
    }
    spin_unlock_bh(&g_binding_lock);
    /* Walk the list of PDs and stop each one. This causes the PD to be
     * removed from the list so we can just pull each one from the head
     * of the list.
     */
    spin_lock_bh(&g_polling_lock);
    while (!list_empty(&g_pd_list)) {
        struct oz_pd *pd =
            list_first_entry(&g_pd_list, struct oz_pd, link);
        oz_pd_get(pd);
        spin_unlock_bh(&g_polling_lock);
        oz_pd_stop(pd);
        oz_pd_put(pd);
        spin_lock_bh(&g_polling_lock);
    }
    chain = g_timer_pool;
    g_timer_pool = 0;
    spin_unlock_bh(&g_polling_lock);
    while (chain) {
        struct oz_timer *t = container_of(chain, struct oz_timer, link);
        chain = chain->next;
        kfree(t);
    }
    oz_trace("Protocol stopped\n");
}
/*------------------------------------------------------------------------------
 * Context: softirq
 */
static void oz_pd_handle_timer(struct oz_pd *pd, int type)
{
    switch (type) {
    case OZ_TIMER_TOUT:
        oz_pd_sleep(pd);
        break;
    case OZ_TIMER_STOP:
        oz_pd_stop(pd);
        break;
    case OZ_TIMER_HEARTBEAT: {
            u16 apps = 0;
            spin_lock_bh(&g_polling_lock);
            pd->heartbeat_requested = 0;
            if (pd->state & OZ_PD_S_CONNECTED)
                apps = pd->total_apps;
            spin_unlock_bh(&g_polling_lock);
            if (apps)
                oz_pd_heartbeat(pd, apps);
        }
        break;
    }
}
/*------------------------------------------------------------------------------
 * Context: softirq
 */
static void oz_protocol_timer(unsigned long arg)
{
    struct oz_timer *t;
    struct oz_timer *t2;
    struct oz_pd *pd;
    spin_lock_bh(&g_polling_lock);
    if (!g_cur_timer) {
        /* This happens if we remove the current timer but can't stop
         * the timer from firing. In this case just get out.
         */
        oz_event_log(OZ_EVT_TIMER, 0, 0, 0, 0);
        spin_unlock_bh(&g_polling_lock);
        return;
    }
    g_timer_state = OZ_TIMER_IN_HANDLER;
    t = g_cur_timer;
    g_cur_timer = 0;
    list_del(&t->link);
    spin_unlock_bh(&g_polling_lock);
    do {
        pd = t->pd;
        oz_event_log(OZ_EVT_TIMER, 0, t->type, 0, 0);
        oz_pd_handle_timer(pd, t->type);
        spin_lock_bh(&g_polling_lock);
        if (g_timer_pool_count < OZ_MAX_TIMER_POOL_SIZE) {
            t->link.next = g_timer_pool;
            g_timer_pool = &t->link;
            g_timer_pool_count++;
            t = 0;
        }
        if (!list_empty(&g_timer_list)) {
            t2 =  container_of(g_timer_list.next,
                struct oz_timer, link);
            if (time_before_eq(t2->due_time, jiffies))
                list_del(&t2->link);
            else
                t2 = 0;
        } else {
            t2 = 0;
        }
        spin_unlock_bh(&g_polling_lock);
        oz_pd_put(pd);
        if (t)
            kfree(t);
        t = t2;
    } while (t);
    g_timer_state = OZ_TIMER_IDLE;
    oz_protocol_timer_start();
}
/*------------------------------------------------------------------------------
 * Context: softirq
 */
static void oz_protocol_timer_start(void)
{
    spin_lock_bh(&g_polling_lock);
    if (!list_empty(&g_timer_list)) {
        g_cur_timer =
            container_of(g_timer_list.next, struct oz_timer, link);
        if (g_timer_state == OZ_TIMER_SET) {
            oz_event_log(OZ_EVT_TIMER_CTRL, 3,
                (u16)g_cur_timer->type, 0,
                (unsigned)g_cur_timer->due_time);
            mod_timer(&g_timer, g_cur_timer->due_time);
        } else {
            oz_event_log(OZ_EVT_TIMER_CTRL, 4,
                (u16)g_cur_timer->type, 0,
                (unsigned)g_cur_timer->due_time);
            g_timer.expires = g_cur_timer->due_time;
            g_timer.function = oz_protocol_timer;
            g_timer.data = 0;
            add_timer(&g_timer);
        }
        g_timer_state = OZ_TIMER_SET;
    } else {
        oz_trace("No queued timers\n");
    }
    spin_unlock_bh(&g_polling_lock);
}
/*------------------------------------------------------------------------------
 * Context: softirq or process
 */
void oz_timer_add(struct oz_pd *pd, int type, unsigned long due_time,
        int remove)
{
    struct list_head *e;
    struct oz_timer *t = 0;
    int restart_needed = 0;
    oz_event_log(OZ_EVT_TIMER_CTRL, 1, (u16)type, 0, (unsigned)due_time);
    spin_lock(&g_polling_lock);
    if (remove) {
        list_for_each(e, &g_timer_list) {
            t = container_of(e, struct oz_timer, link);
            if ((t->pd == pd) && (t->type == type)) {
                if (g_cur_timer == t) {
                    restart_needed = 1;
                    g_cur_timer = 0;
                }
                list_del(e);
                break;
            }
            t = 0;
        }
    }
    if (!t) {
        if (g_timer_pool) {
            t = container_of(g_timer_pool, struct oz_timer, link);
            g_timer_pool = g_timer_pool->next;
            g_timer_pool_count--;
        } else {
            t = kmalloc(sizeof(struct oz_timer), GFP_ATOMIC);
        }
        if (t) {
            t->pd = pd;
            t->type = type;
            oz_pd_get(pd);
        }
    }
    if (t) {
        struct oz_timer *t2;
        t->due_time = due_time;
        list_for_each(e, &g_timer_list) {
            t2 = container_of(e, struct oz_timer, link);
            if (time_before(due_time, t2->due_time)) {
                if (t2 == g_cur_timer) {
                    g_cur_timer = 0;
                    restart_needed = 1;
                }
                break;
            }
        }
        list_add_tail(&t->link, e);
    }
    if (g_timer_state == OZ_TIMER_IDLE)
        restart_needed = 1;
    else if (g_timer_state == OZ_TIMER_IN_HANDLER)
        restart_needed = 0;
    spin_unlock(&g_polling_lock);
    if (restart_needed)
        oz_protocol_timer_start();
}
/*------------------------------------------------------------------------------
 * Context: softirq or process
 */
void oz_timer_delete(struct oz_pd *pd, int type)
{
    struct list_head *chain = 0;
    struct oz_timer *t;
    struct oz_timer *n;
    int restart_needed = 0;
    int release = 0;
    oz_event_log(OZ_EVT_TIMER_CTRL, 2, (u16)type, 0, 0);
    spin_lock(&g_polling_lock);
    list_for_each_entry_safe(t, n, &g_timer_list, link) {
        if ((t->pd == pd) && ((type == 0) || (t->type == type))) {
            if (g_cur_timer == t) {
                restart_needed = 1;
                g_cur_timer = 0;
                del_timer(&g_timer);
            }
            list_del(&t->link);
            release++;
            if (g_timer_pool_count < OZ_MAX_TIMER_POOL_SIZE) {
                t->link.next = g_timer_pool;
                g_timer_pool = &t->link;
                g_timer_pool_count++;
            } else {
                t->link.next = chain;
                chain = &t->link;
            }
            if (type)
                break;
        }
    }
    if (g_timer_state == OZ_TIMER_IN_HANDLER)
        restart_needed = 0;
    else if (restart_needed)
        g_timer_state = OZ_TIMER_IDLE;
    spin_unlock(&g_polling_lock);
    if (restart_needed)
        oz_protocol_timer_start();
    while (release--)
        oz_pd_put(pd);
    while (chain) {
        t = container_of(chain, struct oz_timer, link);
        chain = chain->next;
        kfree(t);
    }
}
/*------------------------------------------------------------------------------
 * Context: softirq or process
 */
void oz_pd_request_heartbeat(struct oz_pd *pd)
{
    unsigned long now = jiffies;
    unsigned long t;
    spin_lock(&g_polling_lock);
    if (pd->heartbeat_requested) {
        spin_unlock(&g_polling_lock);
        return;
    }
    if (pd->pulse_period_j)
        t = ((now / pd->pulse_period_j) + 1) * pd->pulse_period_j;
    else
        t = now + 1;
    pd->heartbeat_requested = 1;
    spin_unlock(&g_polling_lock);
    oz_timer_add(pd, OZ_TIMER_HEARTBEAT, t, 0);
}
/*------------------------------------------------------------------------------
 * Context: softirq or process
 */
struct oz_pd *oz_pd_find(u8 *mac_addr)
{
    struct oz_pd *pd;
    struct list_head *e;
    spin_lock_bh(&g_polling_lock);
    list_for_each(e, &g_pd_list) {
        pd = container_of(e, struct oz_pd, link);
        if (memcmp(pd->mac_addr, mac_addr, ETH_ALEN) == 0) {
            atomic_inc(&pd->ref_count);
            spin_unlock_bh(&g_polling_lock);
            return pd;
        }
    }
    spin_unlock_bh(&g_polling_lock);
    return 0;
}
/*------------------------------------------------------------------------------
 * Context: process
 */
void oz_app_enable(int app_id, int enable)
{
    if (app_id <= OZ_APPID_MAX) {
        spin_lock_bh(&g_polling_lock);
        if (enable)
            g_apps |= (1<<app_id);
        else
            g_apps &= ~(1<<app_id);
        spin_unlock_bh(&g_polling_lock);
    }
}
/*------------------------------------------------------------------------------
 * Context: softirq
 */
static int oz_pkt_recv(struct sk_buff *skb, struct net_device *dev,
        struct packet_type *pt, struct net_device *orig_dev)
{
    oz_event_log(OZ_EVT_RX_FRAME, 0, 0, 0, 0);
    skb = skb_share_check(skb, GFP_ATOMIC);
    if (skb == 0)
        return 0;
    spin_lock_bh(&g_rx_queue.lock);
    if (g_processing_rx) {
        /* We already hold the lock so use __ variant.
         */
        __skb_queue_head(&g_rx_queue, skb);
        spin_unlock_bh(&g_rx_queue.lock);
    } else {
        g_processing_rx = 1;
        do {

            spin_unlock_bh(&g_rx_queue.lock);
            oz_rx_frame(skb);
            spin_lock_bh(&g_rx_queue.lock);
            if (skb_queue_empty(&g_rx_queue)) {
                g_processing_rx = 0;
                spin_unlock_bh(&g_rx_queue.lock);
                break;
            }
            /* We already hold the lock so use __ variant.
             */
            skb = __skb_dequeue(&g_rx_queue);
        } while (1);
    }
    return 0;
}
/*------------------------------------------------------------------------------
 * Context: process
 */
void oz_binding_add(char *net_dev)
{
    struct oz_binding *binding;

    binding = kmalloc(sizeof(struct oz_binding), GFP_KERNEL);
    if (binding) {
        binding->ptype.type = __constant_htons(OZ_ETHERTYPE);
        binding->ptype.func = oz_pkt_recv;
        memcpy(binding->name, net_dev, OZ_MAX_BINDING_LEN);
        if (net_dev && *net_dev) {
            oz_trace("Adding binding: %s\n", net_dev);
            binding->ptype.dev =
                dev_get_by_name(&init_net, net_dev);
            if (binding->ptype.dev == 0) {
                oz_trace("Netdev %s not found\n", net_dev);
                kfree(binding);
                binding = 0;
            }
        } else {
            oz_trace("Binding to all netcards\n");
            binding->ptype.dev = 0;
        }
        if (binding) {
            dev_add_pack(&binding->ptype);
            spin_lock_bh(&g_binding_lock);
            binding->next = g_binding;
            g_binding = binding;
            spin_unlock_bh(&g_binding_lock);
        }
    }
}
/*------------------------------------------------------------------------------
 * Context: process
 */
static int compare_binding_name(char *s1, char *s2)
{
    int i;
    for (i = 0; i < OZ_MAX_BINDING_LEN; i++) {
        if (*s1 != *s2)
            return 0;
        if (!*s1++)
            return 1;
        s2++;
    }
    return 1;
}
/*------------------------------------------------------------------------------
 * Context: process
 */
static void pd_stop_all_for_device(struct net_device *net_dev)
{
    struct list_head h;
    struct oz_pd *pd;
    struct oz_pd *n;
    INIT_LIST_HEAD(&h);
    spin_lock_bh(&g_polling_lock);
    list_for_each_entry_safe(pd, n, &g_pd_list, link) {
        if (pd->net_dev == net_dev) {
            list_move(&pd->link, &h);
            oz_pd_get(pd);
        }
    }
    spin_unlock_bh(&g_polling_lock);
    while (!list_empty(&h)) {
        pd = list_first_entry(&h, struct oz_pd, link);
        oz_pd_stop(pd);
        oz_pd_put(pd);
    }
}
/*------------------------------------------------------------------------------
 * Context: process
 */
void oz_binding_remove(char *net_dev)
{
    struct oz_binding *binding = 0;
    struct oz_binding **link;
    oz_trace("Removing binding: %s\n", net_dev);
    spin_lock_bh(&g_binding_lock);
    binding = g_binding;
    link = &g_binding;
    while (binding) {
        if (compare_binding_name(binding->name, net_dev)) {
            oz_trace("Binding '%s' found\n", net_dev);
            *link = binding->next;
            break;
        } else {
            link = &binding;
            binding = binding->next;
        }
    }
    spin_unlock_bh(&g_binding_lock);
    if (binding) {
        dev_remove_pack(&binding->ptype);
        if (binding->ptype.dev) {
            dev_put(binding->ptype.dev);
            pd_stop_all_for_device(binding->ptype.dev);
        }
        kfree(binding);
    }
}
/*------------------------------------------------------------------------------
 * Context: process
 */
static char *oz_get_next_device_name(char *s, char *dname, int max_size)
{
    while (*s == ',')
        s++;
    while (*s && (*s != ',') && max_size > 1) {
        *dname++ = *s++;
        max_size--;
    }
    *dname = 0;
    return s;
}
/*------------------------------------------------------------------------------
 * Context: process
 */
int oz_protocol_init(char *devs)
{
    skb_queue_head_init(&g_rx_queue);
    if (devs && (devs[0] == '*')) {
        oz_binding_add(0);
    } else {
        char d[32];
        while (*devs) {
            devs = oz_get_next_device_name(devs, d, sizeof(d));
            if (d[0])
                oz_binding_add(d);
        }
    }
    init_timer(&g_timer);
    return 0;
}
/*------------------------------------------------------------------------------
 * Context: process
 */
int oz_get_pd_list(struct oz_mac_addr *addr, int max_count)
{
    struct oz_pd *pd;
    struct list_head *e;
    int count = 0;
    spin_lock_bh(&g_polling_lock);
    list_for_each(e, &g_pd_list) {
        if (count >= max_count)
            break;
        pd = container_of(e, struct oz_pd, link);
        memcpy(&addr[count++], pd->mac_addr, ETH_ALEN);
    }
    spin_unlock_bh(&g_polling_lock);
    return count;
}
/*------------------------------------------------------------------------------
*/
void oz_polling_lock_bh(void)
{
    spin_lock_bh(&g_polling_lock);
}
/*------------------------------------------------------------------------------
*/
void oz_polling_unlock_bh(void)
{
    spin_unlock_bh(&g_polling_lock);
}