iwl-notif-wait.c

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/******************************************************************************
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 * Copyright(c) 2007 - 2012 Intel Corporation. All rights reserved.
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#include <linux/sched.h>
#include <linux/export.h>

#include "iwl-notif-wait.h"


void iwl_notification_wait_init(struct iwl_notif_wait_data *notif_wait)
{
    spin_lock_init(&notif_wait->notif_wait_lock);
    INIT_LIST_HEAD(&notif_wait->notif_waits);
    init_waitqueue_head(&notif_wait->notif_waitq);
}
EXPORT_SYMBOL_GPL(iwl_notification_wait_init);

void iwl_notification_wait_notify(struct iwl_notif_wait_data *notif_wait,
                  struct iwl_rx_packet *pkt)
{
    bool triggered = false;

    if (!list_empty(&notif_wait->notif_waits)) {
        struct iwl_notification_wait *w;

        spin_lock(&notif_wait->notif_wait_lock);
        list_for_each_entry(w, &notif_wait->notif_waits, list) {
            int i;
            bool found = false;

            /*
             * If it already finished (triggered) or has been
             * aborted then don't evaluate it again to avoid races,
             * Otherwise the function could be called again even
             * though it returned true before
             */
            if (w->triggered || w->aborted)
                continue;

            for (i = 0; i < w->n_cmds; i++) {
                if (w->cmds[i] == pkt->hdr.cmd) {
                    found = true;
                    break;
                }
            }
            if (!found)
                continue;

            if (!w->fn || w->fn(notif_wait, pkt, w->fn_data)) {
                w->triggered = true;
                triggered = true;
            }
        }
        spin_unlock(&notif_wait->notif_wait_lock);

    }

    if (triggered)
        wake_up_all(&notif_wait->notif_waitq);
}
EXPORT_SYMBOL_GPL(iwl_notification_wait_notify);

void iwl_abort_notification_waits(struct iwl_notif_wait_data *notif_wait)
{
    struct iwl_notification_wait *wait_entry;

    spin_lock(&notif_wait->notif_wait_lock);
    list_for_each_entry(wait_entry, &notif_wait->notif_waits, list)
        wait_entry->aborted = true;
    spin_unlock(&notif_wait->notif_wait_lock);

    wake_up_all(&notif_wait->notif_waitq);
}
EXPORT_SYMBOL_GPL(iwl_abort_notification_waits);

void
iwl_init_notification_wait(struct iwl_notif_wait_data *notif_wait,
               struct iwl_notification_wait *wait_entry,
               const u8 *cmds, int n_cmds,
               bool (*fn)(struct iwl_notif_wait_data *notif_wait,
                      struct iwl_rx_packet *pkt, void *data),
               void *fn_data)
{
    if (WARN_ON(n_cmds > MAX_NOTIF_CMDS))
        n_cmds = MAX_NOTIF_CMDS;

    wait_entry->fn = fn;
    wait_entry->fn_data = fn_data;
    wait_entry->n_cmds = n_cmds;
    memcpy(wait_entry->cmds, cmds, n_cmds);
    wait_entry->triggered = false;
    wait_entry->aborted = false;

    spin_lock_bh(&notif_wait->notif_wait_lock);
    list_add(&wait_entry->list, &notif_wait->notif_waits);
    spin_unlock_bh(&notif_wait->notif_wait_lock);
}
EXPORT_SYMBOL_GPL(iwl_init_notification_wait);

int iwl_wait_notification(struct iwl_notif_wait_data *notif_wait,
              struct iwl_notification_wait *wait_entry,
              unsigned long timeout)
{
    int ret;

    ret = wait_event_timeout(notif_wait->notif_waitq,
                 wait_entry->triggered || wait_entry->aborted,
                 timeout);

    spin_lock_bh(&notif_wait->notif_wait_lock);
    list_del(&wait_entry->list);
    spin_unlock_bh(&notif_wait->notif_wait_lock);

    if (wait_entry->aborted)
        return -EIO;

    /* return value is always >= 0 */
    if (ret <= 0)
        return -ETIMEDOUT;
    return 0;
}
EXPORT_SYMBOL_GPL(iwl_wait_notification);

void iwl_remove_notification(struct iwl_notif_wait_data *notif_wait,
                 struct iwl_notification_wait *wait_entry)
{
    spin_lock_bh(&notif_wait->notif_wait_lock);
    list_del(&wait_entry->list);
    spin_unlock_bh(&notif_wait->notif_wait_lock);
}
EXPORT_SYMBOL_GPL(iwl_remove_notification);