xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mac80211: station state transition error handling

Browse Source 
In the future, when we start notifying drivers,
state transitions could potentially fail. To make
it easier to distinguish between programming bugs
and driver failures:
 * rename sta_info_move_state() to
   sta_info_pre_move_state() which can only be
   called before the station is inserted (and
   check this with a new station flag).
 * rename sta_info_move_state_checked() to just
   plain sta_info_move_state(), as it will be
   the regular function that can fail for more
   than just one reason (bad transition or an
   error from the driver)

This makes the programming model easier -- one of
the functions can only be called before insertion
and can't fail, the other can fail.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg
2012-01-12 09:31:10 +01:00
committed by John W. Linville
parent c037b8367c
commit 83d5cc0124
8 changed files with 59 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
net/mac80211/sta_info.c
View File

@@ -403,6 +403,8 @@ static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU)
sta_info_hash_add(local, sta);
list_add(&sta->list, &local->sta_list);
set_sta_flag(sta, WLAN_STA_INSERTED);
} else {
sta->dummy = false;
}
@@ -707,7 +709,7 @@ static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
return have_buffered;
}
static int __must_check __sta_info_destroy(struct sta_info *sta)
int __must_check __sta_info_destroy(struct sta_info *sta)
{
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
@@ -722,6 +724,8 @@ static int __must_check __sta_info_destroy(struct sta_info *sta)
local = sta->local;
sdata = sta->sdata;
lockdep_assert_held(&local->sta_mtx);
/*
* Before removing the station from the driver and
* rate control, it might still start new aggregation
@@ -763,8 +767,13 @@ static int __must_check __sta_info_destroy(struct sta_info *sta)
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
while (sta->sta_state > IEEE80211_STA_NONE)
sta_info_move_state(sta, sta->sta_state - 1);
while (sta->sta_state > IEEE80211_STA_NONE) {
int err = sta_info_move_state(sta, sta->sta_state - 1);
if (err) {
WARN_ON_ONCE(1);
break;
}
}
if (sta->uploaded) {
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
@@ -1391,8 +1400,8 @@ void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
}
EXPORT_SYMBOL(ieee80211_sta_set_buffered);
int sta_info_move_state_checked(struct sta_info *sta,
enum ieee80211_sta_state new_state)
int sta_info_move_state(struct sta_info *sta,
enum ieee80211_sta_state new_state)
{
might_sleep();