mac80211: reschedule sched scan after HW restart

Keep the sched scan req when starting sched scan, and reschedule
it in case of HW restart during sched scan.
The upper layer don't have to know about the restart.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 2874628758579d21d26e2f64167e862f418a20db..ee13c6593b9ab344c82ea138b4f977e0a4e3c3f2 100644 (file)
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1113,6 +1113,7 @@ struct ieee80211_local {
 
        struct work_struct sched_scan_stopped_work;
        struct ieee80211_sub_if_data __rcu *sched_scan_sdata;
+       struct cfg80211_sched_scan_request *sched_scan_req;
 
        unsigned long leave_oper_channel_time;
        enum mac80211_scan_state next_scan_state;
@@ -1421,6 +1422,9 @@ void ieee80211_rx_bss_put(struct ieee80211_local *local,
                          struct ieee80211_bss *bss);
 
 /* scheduled scan handling */
+int
+__ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
+                                    struct cfg80211_sched_scan_request *req);
 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
                                       struct cfg80211_sched_scan_request *req);
 int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata);

diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index fa34cd2344b98b9615a940a00e78363b494bc06c..2bd5b552b2f6c41629022876265bdd9a10e8890e 100644 (file)
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -250,12 +250,8 @@ static void ieee80211_restart_work(struct work_struct *work)
        /* wait for scan work complete */
        flush_workqueue(local->workqueue);
 
-       mutex_lock(&local->mtx);
-       WARN(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
-            rcu_dereference_protected(local->sched_scan_sdata,
-                                      lockdep_is_held(&local->mtx)),
-               "%s called with hardware scan in progress\n", __func__);
-       mutex_unlock(&local->mtx);
+       WARN(test_bit(SCAN_HW_SCANNING, &local->scanning),
+            "%s called with hardware scan in progress\n", __func__);
 
        rtnl_lock();
        ieee80211_scan_cancel(local);

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index ee6c8515f97b139620bb3dd1b4dbe85ae77b78ba..88c81616f8f758595e90cced1d503448ce6ba969 100644 (file)
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -971,8 +971,8 @@ out:
        mutex_unlock(&local->mtx);
 }
 
-int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
-                                      struct cfg80211_sched_scan_request *req)
+int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
+                                       struct cfg80211_sched_scan_request *req)
 {
        struct ieee80211_local *local = sdata->local;
        struct ieee80211_sched_scan_ies sched_scan_ies = {};
@@ -982,17 +982,10 @@ int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
        iebufsz = 2 + IEEE80211_MAX_SSID_LEN +
                  local->scan_ies_len + req->ie_len;
 
-       mutex_lock(&local->mtx);
+       lockdep_assert_held(&local->mtx);
 
-       if (rcu_access_pointer(local->sched_scan_sdata)) {
-               ret = -EBUSY;
-               goto out;
-       }
-
-       if (!local->ops->sched_scan_start) {
-               ret = -ENOTSUPP;
-               goto out;
-       }
+       if (!local->ops->sched_scan_start)
+               return -ENOTSUPP;
 
        for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
                if (!local->hw.wiphy->bands[i])
@@ -1013,13 +1006,39 @@ int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
        }
 
        ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
-       if (ret == 0)
+       if (ret == 0) {
                rcu_assign_pointer(local->sched_scan_sdata, sdata);
+               local->sched_scan_req = req;
+       }
 
 out_free:
        while (i > 0)
                kfree(sched_scan_ies.ie[--i]);
-out:
+
+       if (ret) {
+               /* Clean in case of failure after HW restart or upon resume. */
+               rcu_assign_pointer(local->sched_scan_sdata, NULL);
+               local->sched_scan_req = NULL;
+       }
+
+       return ret;
+}
+
+int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
+                                      struct cfg80211_sched_scan_request *req)
+{
+       struct ieee80211_local *local = sdata->local;
+       int ret;
+
+       mutex_lock(&local->mtx);
+
+       if (rcu_access_pointer(local->sched_scan_sdata)) {
+               mutex_unlock(&local->mtx);
+               return -EBUSY;
+       }
+
+       ret = __ieee80211_request_sched_scan_start(sdata, req);
+
        mutex_unlock(&local->mtx);
        return ret;
 }
@@ -1036,6 +1055,9 @@ int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata)
                goto out;
        }
 
+       /* We don't want to restart sched scan anymore. */
+       local->sched_scan_req = NULL;
+
        if (rcu_access_pointer(local->sched_scan_sdata))
                drv_sched_scan_stop(local, sdata);
 
@@ -1070,6 +1092,9 @@ void ieee80211_sched_scan_stopped_work(struct work_struct *work)
 
        rcu_assign_pointer(local->sched_scan_sdata, NULL);
 
+       /* If sched scan was aborted by the driver. */
+       local->sched_scan_req = NULL;
+
        mutex_unlock(&local->mtx);
 
        cfg80211_sched_scan_stopped(local->hw.wiphy);

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index adf81f02368195eb62ca1f2ccb2d9ef947f6189d..591b46b724621dedfba73cedeb9791c0608339b8 100644 (file)
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1462,6 +1462,8 @@ int ieee80211_reconfig(struct ieee80211_local *local)
        struct sta_info *sta;
        int res, i;
        bool reconfig_due_to_wowlan = false;
+       struct ieee80211_sub_if_data *sched_scan_sdata;
+       bool sched_scan_stopped = false;
 
 #ifdef CONFIG_PM
        if (local->suspended)
@@ -1765,6 +1767,27 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 #else
        WARN_ON(1);
 #endif
+
+       /*
+        * Reconfigure sched scan if it was interrupted by FW restart or
+        * suspend.
+        */
+       mutex_lock(&local->mtx);
+       sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
+                                               lockdep_is_held(&local->mtx));
+       if (sched_scan_sdata && local->sched_scan_req)
+               /*
+                * Sched scan stopped, but we don't want to report it. Instead,
+                * we're trying to reschedule.
+                */
+               if (__ieee80211_request_sched_scan_start(sched_scan_sdata,
+                                                        local->sched_scan_req))
+                       sched_scan_stopped = true;
+       mutex_unlock(&local->mtx);
+
+       if (sched_scan_stopped)
+               cfg80211_sched_scan_stopped(local->hw.wiphy);
+
        return 0;
 }