mac80211: cancel/restart all timers across suspend/resume

We forgot to cancel all timers in mac80211 when suspending.
In particular we forgot to deal with some things that can
cause hardware reconfiguration -- while it is down.

While at it we go ahead and add a warning in ieee80211_sta_work()
if its run while the suspend->resume cycle is in effect. This
should not happen and if it does it would indicate there is
a bug lurking in either mac80211 or mac80211 drivers.

With this now wpa_supplicant doesn't blink when I go to suspend
and resume where as before there where issues with some timers
running during the suspend->resume cycle. This caused a lot of
incorrect assumptions and would at times bring back the device
in an incoherent, but mostly recoverable, state.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index be9446551cf6..8db8d16d206c 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -293,6 +293,7 @@ struct ieee80211_if_managed {
         int auth_tries; /* retries for auth req */
         int assoc_tries; /* retries for assoc req */
 
+        unsigned long timers_running; /* used for quiesce/restart */
         bool powersave; /* powersave requested for this iface */
 
         unsigned long request;
@@ -333,6 +334,9 @@ struct ieee80211_if_ibss {
 
         unsigned long request;
         unsigned long last_scan_completed;
+
+        bool timer_running;
+
         bool fixed_bssid;
         bool fixed_channel;
 
@@ -358,6 +362,8 @@ struct ieee80211_if_mesh {
         struct timer_list mesh_path_timer;
         struct sk_buff_head skb_queue;
 
+        unsigned long timers_running;
+
         bool housekeeping;
 
         u8 mesh_id[IEEE80211_MAX_MESH_ID_LEN];
@@ -609,6 +615,21 @@ struct ieee80211_local {
         unsigned int filter_flags; /* FIF_* */
         struct iw_statistics wstats;
         bool tim_in_locked_section; /* see ieee80211_beacon_get() */
+
+        /*
+         * suspended is true if we finished all the suspend _and_ we have
+         * not yet come up from resume. This is to be used by mac80211
+         * to ensure driver sanity during suspend and mac80211's own
+         * sanity. It can eventually be used for WoW as well.
+         */
+        bool suspended;
+
+        /*
+         * quiescing is true during the suspend process _only_ to
+         * ease timer cancelling etc.
+         */
+        bool quiescing;
+
         int tx_headroom; /* required headroom for hardware/radiotap */
 
         /* Tasklet and skb queue to process calls from IRQ mode. All frames
@@ -937,6 +958,8 @@ int ieee80211_max_network_latency(struct notifier_block *nb,
 void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
                                       struct ieee80211_channel_sw_ie *sw_elem,
                                       struct ieee80211_bss *bss);
+void ieee80211_sta_quiesce(struct ieee80211_sub_if_data *sdata);
+void ieee80211_sta_restart(struct ieee80211_sub_if_data *sdata);
 
 /* IBSS code */
 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local);
@@ -949,6 +972,8 @@ struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
                         struct cfg80211_ibss_params *params);
 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata);
+void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata);
+void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata);
 
 /* scan/BSS handling */
 void ieee80211_scan_work(struct work_struct *work);
@@ -959,6 +984,7 @@ int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
 int ieee80211_scan_results(struct ieee80211_local *local,
                            struct iw_request_info *info,
                            char *buf, size_t len);
+void ieee80211_scan_cancel(struct ieee80211_local *local);
 ieee80211_rx_result
 ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata,
                   struct sk_buff *skb,