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>

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);

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 */

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);