When the driver has been notified with a STA_REMOVE, it tears down
the internal ADDBA state. On resume, trying to initiate aggregation would
fail because mac80211 has not cleared the operational state for that <TID,STA>.
This can be fixed by tearing down the existing sessions on a suspend.
Also, the driver can initiate a new BA session when suspend is in progress.
This is fixed by marking the station as being in suspend state and
denying ADDBA requests for such STAs.
Signed-off-by: Sujith <[email protected]>
---
(SMTP borkage, try again)
v2:
--
* Deny ADDBA requests if suspend is in progress.
net/mac80211/agg-rx.c | 8 ++++++++
net/mac80211/agg-tx.c | 9 +++++++++
net/mac80211/pm.c | 15 +++++++++++++++
net/mac80211/sta_info.h | 3 +++
4 files changed, 35 insertions(+), 0 deletions(-)
diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index a95affc..07656d8 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -197,6 +197,14 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
status = WLAN_STATUS_REQUEST_DECLINED;
+ if (test_sta_flags(sta, WLAN_STA_SUSPEND)) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Suspend in progress. "
+ "Denying ADDBA request\n");
+#endif
+ goto end_no_lock;
+ }
+
/* sanity check for incoming parameters:
* check if configuration can support the BA policy
* and if buffer size does not exceeds max value */
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 1df116d..e5776ef 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -257,6 +257,15 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
goto unlock;
}
+ if (test_sta_flags(sta, WLAN_STA_SUSPEND)) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Suspend in progress. "
+ "Denying BA session request\n");
+#endif
+ ret = -EINVAL;
+ goto unlock;
+ }
+
spin_lock_bh(&sta->lock);
sdata = sta->sdata;
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index f845601..07929fb 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -21,6 +21,14 @@ int __ieee80211_suspend(struct ieee80211_hw *hw)
list_for_each_entry(sdata, &local->interfaces, list)
ieee80211_disable_keys(sdata);
+ /* Tear down aggregation sessions */
+ if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+ list_for_each_entry(sta, &local->sta_list, list) {
+ set_sta_flags(sta, WLAN_STA_SUSPEND);
+ ieee80211_sta_tear_down_BA_sessions(sta);
+ }
+ }
+
/* remove STAs */
if (local->ops->sta_notify) {
spin_lock_irqsave(&local->sta_lock, flags);
@@ -102,6 +110,13 @@ int __ieee80211_resume(struct ieee80211_hw *hw)
spin_unlock_irqrestore(&local->sta_lock, flags);
}
+ /* Clear Suspend state so that ADDBA requests can be processed */
+ if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
+ list_for_each_entry(sta, &local->sta_list, list) {
+ clear_sta_flags(sta, WLAN_STA_SUSPEND);
+ }
+ }
+
/* add back keys */
list_for_each_entry(sdata, &local->interfaces, list)
if (netif_running(sdata->dev))
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 1f45573..5b223b2 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -35,6 +35,8 @@
* IEEE80211_TX_CTL_CLEAR_PS_FILT control flag) when the next
* frame to this station is transmitted.
* @WLAN_STA_MFP: Management frame protection is used with this STA.
+ * @WLAN_STA_SUSPEND: Set/cleared during a suspend/resume cycle.
+ * Used to deny ADDBA requests (both TX and RX).
*/
enum ieee80211_sta_info_flags {
WLAN_STA_AUTH = 1<<0,
@@ -48,6 +50,7 @@ enum ieee80211_sta_info_flags {
WLAN_STA_PSPOLL = 1<<8,
WLAN_STA_CLEAR_PS_FILT = 1<<9,
WLAN_STA_MFP = 1<<10,
+ WLAN_STA_SUSPEND = 1<<11
};
#define STA_TID_NUM 16
--
1.6.2
On Mon, 2009-03-16 at 15:35 +0530, Sujith wrote:
> + /* Tear down aggregation sessions */
> + if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
> + list_for_each_entry(sta, &local->sta_list, list) {
> + set_sta_flags(sta, WLAN_STA_SUSPEND);
> + ieee80211_sta_tear_down_BA_sessions(sta);
> + }
> + }
Doesn't that, and the corresponding code in resume, need to be using the
rcu-safe list iteration primitives and rcu_read_lock(), or acquire the
sta_lock like the other iteration? While we should be more or less
quiescent at this point, I wouldn't really want to bet on it.
johannes
Johannes Berg wrote:
> Good catch, that does seem a little complicated. This way is good
> anyway, so let's stick to it, at least for now.
Ok.
Thanks for the review.
SUjith
Johannes Berg wrote:
> On Mon, 2009-03-16 at 15:35 +0530, Sujith wrote:
>
> > + /* Tear down aggregation sessions */
> > + if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
> > + list_for_each_entry(sta, &local->sta_list, list) {
> > + set_sta_flags(sta, WLAN_STA_SUSPEND);
> > + ieee80211_sta_tear_down_BA_sessions(sta);
> > + }
> > + }
>
> Doesn't that, and the corresponding code in resume, need to be using the
> rcu-safe list iteration primitives and rcu_read_lock(), or acquire the
> sta_lock like the other iteration? While we should be more or less
> quiescent at this point, I wouldn't really want to bet on it.
Ah, right, it should be rcu-protected.
Will send out a v3 tomorrow.
Sujith