android_kernel_xiaomi_sm8350/net/ieee80211/softmac/ieee80211softmac_event.c
Johannes Berg 501d857ec9 [IEEE80211]: Fix softmac lockdep reports.
It seems I was actually able to hit this deadlock, on my quad G5 softmac
locks up more often than not. This fixes it by using an own workqueue
that can safely be flushed under RTNL.

Not sure if the patch is correct with the workqueue naming. And don't
think with the patch it doesn't continually lock up. It still does, just
doesn't invoke lockdep warnings all the time.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:52:22 -07:00

190 lines
5.8 KiB
C

/*
* Event system
* Also see comments in public header file and longer explanation below.
*
* Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
* Joseph Jezak <josejx@gentoo.org>
* Larry Finger <Larry.Finger@lwfinger.net>
* Danny van Dyk <kugelfang@gentoo.org>
* Michael Buesch <mbuesch@freenet.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* The full GNU General Public License is included in this distribution in the
* file called COPYING.
*/
#include "ieee80211softmac_priv.h"
/*
* Each event has associated to it
* - an event type (see constants in public header)
* - an event context (see below)
* - the function to be called
* - a context (extra parameter to call the function with)
* - and the softmac struct
*
* The event context is private and can only be used from
* within this module. Its meaning varies with the event
* type:
* SCAN_FINISHED,
* DISASSOCIATED: NULL
* ASSOCIATED,
* ASSOCIATE_FAILED,
* ASSOCIATE_TIMEOUT,
* AUTHENTICATED,
* AUTH_FAILED,
* AUTH_TIMEOUT: a pointer to the network struct
* ...
* Code within this module can use the event context to be only
* called when the event is true for that specific context
* as per above table.
* If the event context is NULL, then the notification is always called,
* regardless of the event context. The event context is not passed to
* the callback, it is assumed that the context suffices.
*
* You can also use the event context only by setting the event type
* to -1 (private use only), in which case you'll be notified
* whenever the event context matches.
*/
static char *event_descriptions[IEEE80211SOFTMAC_EVENT_LAST+1] = {
NULL, /* scan finished */
NULL, /* associated */
"associating failed",
"associating timed out",
"authenticated",
"authenticating failed",
"authenticating timed out",
"associating failed because no suitable network was found",
NULL, /* disassociated */
};
static void
ieee80211softmac_notify_callback(struct work_struct *work)
{
struct ieee80211softmac_event *pevent =
container_of(work, struct ieee80211softmac_event, work.work);
struct ieee80211softmac_event event = *pevent;
kfree(pevent);
event.fun(event.mac->dev, event.event_type, event.context);
}
int
ieee80211softmac_notify_internal(struct ieee80211softmac_device *mac,
int event, void *event_context, notify_function_ptr fun, void *context, gfp_t gfp_mask)
{
struct ieee80211softmac_event *eventptr;
unsigned long flags;
if (event < -1 || event > IEEE80211SOFTMAC_EVENT_LAST)
return -ENOSYS;
if (!fun)
return -EINVAL;
eventptr = kmalloc(sizeof(struct ieee80211softmac_event), gfp_mask);
if (!eventptr)
return -ENOMEM;
eventptr->event_type = event;
INIT_DELAYED_WORK(&eventptr->work, ieee80211softmac_notify_callback);
eventptr->fun = fun;
eventptr->context = context;
eventptr->mac = mac;
eventptr->event_context = event_context;
spin_lock_irqsave(&mac->lock, flags);
list_add(&eventptr->list, &mac->events);
spin_unlock_irqrestore(&mac->lock, flags);
return 0;
}
int
ieee80211softmac_notify_gfp(struct net_device *dev,
int event, notify_function_ptr fun, void *context, gfp_t gfp_mask)
{
struct ieee80211softmac_device *mac = ieee80211_priv(dev);
if (event < 0 || event > IEEE80211SOFTMAC_EVENT_LAST)
return -ENOSYS;
return ieee80211softmac_notify_internal(mac, event, NULL, fun, context, gfp_mask);
}
EXPORT_SYMBOL_GPL(ieee80211softmac_notify_gfp);
/* private -- calling all callbacks that were specified */
void
ieee80211softmac_call_events_locked(struct ieee80211softmac_device *mac, int event, void *event_ctx)
{
struct ieee80211softmac_event *eventptr, *tmp;
struct ieee80211softmac_network *network;
if (event >= 0) {
union iwreq_data wrqu;
int we_event;
char *msg = NULL;
memset(&wrqu, '\0', sizeof (union iwreq_data));
switch(event) {
case IEEE80211SOFTMAC_EVENT_ASSOCIATED:
network = (struct ieee80211softmac_network *)event_ctx;
memcpy(wrqu.ap_addr.sa_data, &network->bssid[0], ETH_ALEN);
/* fall through */
case IEEE80211SOFTMAC_EVENT_DISASSOCIATED:
wrqu.ap_addr.sa_family = ARPHRD_ETHER;
we_event = SIOCGIWAP;
break;
case IEEE80211SOFTMAC_EVENT_SCAN_FINISHED:
we_event = SIOCGIWSCAN;
break;
default:
msg = event_descriptions[event];
if (!msg)
msg = "SOFTMAC EVENT BUG";
wrqu.data.length = strlen(msg);
we_event = IWEVCUSTOM;
break;
}
wireless_send_event(mac->dev, we_event, &wrqu, msg);
}
if (!list_empty(&mac->events))
list_for_each_entry_safe(eventptr, tmp, &mac->events, list) {
if ((eventptr->event_type == event || eventptr->event_type == -1)
&& (eventptr->event_context == NULL || eventptr->event_context == event_ctx)) {
list_del(&eventptr->list);
/* User may have subscribed to ANY event, so
* we tell them which event triggered it. */
eventptr->event_type = event;
queue_delayed_work(mac->wq, &eventptr->work, 0);
}
}
}
void
ieee80211softmac_call_events(struct ieee80211softmac_device *mac, int event, void *event_ctx)
{
unsigned long flags;
spin_lock_irqsave(&mac->lock, flags);
ieee80211softmac_call_events_locked(mac, event, event_ctx);
spin_unlock_irqrestore(&mac->lock, flags);
}