mac80211: resume properly, add suspend/resume test

When mac80211 resumes, it currently doesn't reconfigure the interfaces
entirely and also doesn't reconfigure BSS information -- fix this.

Also, to be able to test this, add a debugfs file that just calls
the suspend/resume code to see what happens when we go through that,
without needing the time-consuming suspend/resume cycle.

(Original version broke the build for CONFIG_PM=n.  Define alternative
functions for that situation. -- JWL)

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

3 files changed, 65 insertions, 0 deletions

diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index e37f557de3f3..210b9b6fecd2 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -40,6 +40,10 @@ static const struct file_operations name## _ops = {			\
         local->debugfs.name = debugfs_create_file(#name, 0400, phyd,    \
                                                   local, &name## _ops);
 
+#define DEBUGFS_ADD_MODE(name, mode)                                    \
+        local->debugfs.name = debugfs_create_file(#name, mode, phyd,    \
+                                                  local, &name## _ops);
+
 #define DEBUGFS_DEL(name)                                               \
         debugfs_remove(local->debugfs.name);                            \
         local->debugfs.name = NULL;
@@ -113,6 +117,24 @@ static const struct file_operations tsf_ops = {
         .open = mac80211_open_file_generic
 };
 
+static ssize_t reset_write(struct file *file, const char __user *user_buf,
+                           size_t count, loff_t *ppos)
+{
+        struct ieee80211_local *local = file->private_data;
+
+        rtnl_lock();
+        __ieee80211_suspend(&local->hw);
+        __ieee80211_resume(&local->hw);
+        rtnl_unlock();
+
+        return count;
+}
+
+static const struct file_operations reset_ops = {
+        .write = reset_write,
+        .open = mac80211_open_file_generic,
+};
+
 /* statistics stuff */
 
 #define DEBUGFS_STATS_FILE(name, buflen, fmt, value...)                 \
@@ -254,6 +276,7 @@ void debugfs_hw_add(struct ieee80211_local *local)
         DEBUGFS_ADD(total_ps_buffered);
         DEBUGFS_ADD(wep_iv);
         DEBUGFS_ADD(tsf);
+        DEBUGFS_ADD_MODE(reset, 0200);
 
         statsd = debugfs_create_dir("statistics", phyd);
         local->debugfs.statistics = statsd;
@@ -308,6 +331,7 @@ void debugfs_hw_del(struct ieee80211_local *local)
         DEBUGFS_DEL(total_ps_buffered);
         DEBUGFS_DEL(wep_iv);
         DEBUGFS_DEL(tsf);
+        DEBUGFS_DEL(reset);
 
         DEBUGFS_STATS_DEL(transmitted_fragment_count);
         DEBUGFS_STATS_DEL(multicast_transmitted_frame_count);
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 7b96d95f48b1..547cfac218ee 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -780,6 +780,7 @@ struct ieee80211_local {
                 struct dentry *total_ps_buffered;
                 struct dentry *wep_iv;
                 struct dentry *tsf;
+                struct dentry *reset;
                 struct dentry *statistics;
                 struct local_debugfsdentries_statsdentries {
                         struct dentry *transmitted_fragment_count;
@@ -1059,8 +1060,19 @@ void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
                                  u8 pwr_constr_elem_len);
 
 /* Suspend/resume */
+#ifdef CONFIG_PM
 int __ieee80211_suspend(struct ieee80211_hw *hw);
 int __ieee80211_resume(struct ieee80211_hw *hw);
+#else
+static inline int __ieee80211_suspend(struct ieee80211_hw *hw)
+{
+        return 0;
+}
+static inline int __ieee80211_resume(struct ieee80211_hw *hw)
+{
+        return 0;
+}
+#endif
 
 /* utility functions/constants */
 extern void *mac80211_wiphy_privid; /* for wiphy privid */
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index 1e6152ac6778..027302326498 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -143,6 +143,35 @@ int __ieee80211_resume(struct ieee80211_hw *hw)
         ieee80211_configure_filter(local);
         netif_addr_unlock_bh(local->mdev);
 
+        /* Finally also reconfigure all the BSS information */
+        list_for_each_entry(sdata, &local->interfaces, list) {
+                u32 changed = ~0;
+                if (!netif_running(sdata->dev))
+                        continue;
+                switch (sdata->vif.type) {
+                case NL80211_IFTYPE_STATION:
+                        /* disable beacon change bits */
+                        changed &= ~IEEE80211_IFCC_BEACON;
+                        /* fall through */
+                case NL80211_IFTYPE_ADHOC:
+                case NL80211_IFTYPE_AP:
+                case NL80211_IFTYPE_MESH_POINT:
+                        WARN_ON(ieee80211_if_config(sdata, changed));
+                        ieee80211_bss_info_change_notify(sdata, ~0);
+                        break;
+                case NL80211_IFTYPE_WDS:
+                        break;
+                case NL80211_IFTYPE_AP_VLAN:
+                case NL80211_IFTYPE_MONITOR:
+                        /* ignore virtual */
+                        break;
+                case NL80211_IFTYPE_UNSPECIFIED:
+                case __NL80211_IFTYPE_AFTER_LAST:
+                        WARN_ON(1);
+                        break;
+                }
+        }
+
         ieee80211_wake_queues_by_reason(hw,
                         IEEE80211_QUEUE_STOP_REASON_SUSPEND);