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mac80211: assure we also cancel deferred scan request

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This is partial revert and fix for commit
85f72bc839 "mac80211: only cancel
software-based scans on suspend"

When cfg80211 request the scan and mac80211 perform some management work,
we defer the scan request. We do not canceling such requests when calling
ieee80211_scan_cancel(), because of SCAN_SW_SCANNING bit check just
before the call. So fix that problem.

Another problem, which commit 85f72bc839
tries to solve, is we can not cancel HW scan. Hence patch make
ieee80211_scan_cancel() ignore HW scan (see code comments). Keeping
local->mtx lock assures that the deferred scan will not become
"working" HW scan.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Stanislaw Gruszka
2010-10-06 11:22:10 +02:00
committed by John W. Linville
parent e229f844d7
commit 4136c4224c
3 changed files with 27 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
net/mac80211/main.c
View File

@@ -307,8 +307,7 @@ static void ieee80211_restart_work(struct work_struct *work)
mutex_unlock(&local->mtx); mutex_unlock(&local->mtx);
rtnl_lock(); rtnl_lock();
if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning))) ieee80211_scan_cancel(local);
ieee80211_scan_cancel(local);
ieee80211_reconfig(local); ieee80211_reconfig(local);
rtnl_unlock(); rtnl_unlock();
} }

3
net/mac80211/pm.c
View File

@@ -12,8 +12,7 @@ int __ieee80211_suspend(struct ieee80211_hw *hw)
struct ieee80211_sub_if_data *sdata; struct ieee80211_sub_if_data *sdata;
struct sta_info *sta; struct sta_info *sta;
if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning))) ieee80211_scan_cancel(local);
ieee80211_scan_cancel(local);
ieee80211_stop_queues_by_reason(hw, ieee80211_stop_queues_by_reason(hw,
IEEE80211_QUEUE_STOP_REASON_SUSPEND); IEEE80211_QUEUE_STOP_REASON_SUSPEND);

35
net/mac80211/scan.c
View File

@@ -793,24 +793,39 @@ int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata,
return ret; return ret;
} }
/*
* Only call this function when a scan can't be queued -- under RTNL.
*/
void ieee80211_scan_cancel(struct ieee80211_local *local) void ieee80211_scan_cancel(struct ieee80211_local *local)
{ {
bool abortscan; bool abortscan, finish;
bool finish = false;
cancel_delayed_work_sync(&local->scan_work);
/* /*
* Only call this function when a scan can't be * We are only canceling software scan, or deferred scan that was not
* queued -- mostly at suspend under RTNL. * yet really started (see __ieee80211_start_scan ).
*
* Regarding hardware scan:
* - we can not call __ieee80211_scan_completed() as when
* SCAN_HW_SCANNING bit is set this function change
* local->hw_scan_req to operate on 5G band, what race with
* driver which can use local->hw_scan_req
*
* - we can not cancel scan_work since driver can schedule it
* by ieee80211_scan_completed(..., true) to finish scan
*
* Hence low lever driver is responsible for canceling HW scan.
*/ */
mutex_lock(&local->mtx); mutex_lock(&local->mtx);
abortscan = test_bit(SCAN_SW_SCANNING, &local->scanning) || abortscan = local->scan_req && !test_bit(SCAN_HW_SCANNING, &local->scanning);
(!local->scanning && local->scan_req);
if (abortscan) if (abortscan)
finish = __ieee80211_scan_completed(&local->hw, true, false); finish = __ieee80211_scan_completed(&local->hw, true, false);
mutex_unlock(&local->mtx); mutex_unlock(&local->mtx);
if (finish) if (abortscan) {
__ieee80211_scan_completed_finish(&local->hw, false); /* The scan is canceled, but stop work from being pending */
cancel_delayed_work_sync(&local->scan_work);
if (finish)
__ieee80211_scan_completed_finish(&local->hw, false);
}
} }