{nl,cfg}80211: make peer link expiration time configurable

If a STA has a peer that it hasn't seen any tx activity
from for a certain length of time, the peer link is
expired. This means the inactive STA is removed from the
list of peers and that STA is not considered a peer again
unless it re-peers.  Previously, this inactivity time was
always 30 minutes.  Now, add it to the mesh configuration
and allow it to be configured.  Retain 30 minutes as a
default value.
Signed-off-by: Colleen Twitty <colleen@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -1124,6 +1124,9 @@ struct bss_parameters {
  *	setting for new peer links.
  * @dot11MeshAwakeWindowDuration: The duration in TUs the STA will remain awake
  *	after transmitting its beacon.
+ * @plink_timeout: If no tx activity is seen from a STA we've established
+ *	peering with for longer than this time (in seconds), then remove it
+ *	from the STA's list of peers.  Default is 30 minutes.
  */
 struct mesh_config {
 	u16 dot11MeshRetryTimeout;
@@ -1153,6 +1156,7 @@ struct mesh_config {
 	u16 dot11MeshHWMPconfirmationInterval;
 	enum nl80211_mesh_power_mode power_mode;
 	u16 dot11MeshAwakeWindowDuration;
+	u32 plink_timeout;
 };
 
 /**

include/uapi/linux/nl80211.h

@@ -2577,6 +2577,10 @@ enum nl80211_mesh_power_mode {
  *
  * @NL80211_MESHCONF_AWAKE_WINDOW: awake window duration (in TUs)
  *
+ * @NL80211_MESHCONF_PLINK_TIMEOUT: If no tx activity is seen from a STA we've
+ *	established peering with for longer than this time (in seconds), then
+ *	remove it from the STA's list of peers.  Default is 30 minutes.
+ *
  * @__NL80211_MESHCONF_ATTR_AFTER_LAST: internal use
  */
 enum nl80211_meshconf_params {
@@ -2608,6 +2612,7 @@ enum nl80211_meshconf_params {
 	NL80211_MESHCONF_HWMP_CONFIRMATION_INTERVAL,
 	NL80211_MESHCONF_POWER_MODE,
 	NL80211_MESHCONF_AWAKE_WINDOW,
+	NL80211_MESHCONF_PLINK_TIMEOUT,
 
 	/* keep last */
 	__NL80211_MESHCONF_ATTR_AFTER_LAST,

net/wireless/mesh.c

@@ -18,6 +18,7 @@
 #define MESH_PATH_TO_ROOT_TIMEOUT      6000
 #define MESH_ROOT_INTERVAL     5000
 #define MESH_ROOT_CONFIRMATION_INTERVAL 2000
+#define MESH_DEFAULT_PLINK_TIMEOUT	1800 /* timeout in seconds */
 
 /*
  * Minimum interval between two consecutive PREQs originated by the same
@@ -75,6 +76,7 @@ const struct mesh_config default_mesh_config = {
 	.dot11MeshHWMPconfirmationInterval = MESH_ROOT_CONFIRMATION_INTERVAL,
 	.power_mode = NL80211_MESH_POWER_ACTIVE,
 	.dot11MeshAwakeWindowDuration = MESH_DEFAULT_AWAKE_WINDOW,
+	.plink_timeout = MESH_DEFAULT_PLINK_TIMEOUT,
 };
 
 const struct mesh_setup default_mesh_setup = {

net/wireless/nl80211.c

@@ -4575,7 +4575,9 @@ static int nl80211_get_mesh_config(struct sk_buff *skb,
 	    nla_put_u32(msg, NL80211_MESHCONF_POWER_MODE,
 			cur_params.power_mode) ||
 	    nla_put_u16(msg, NL80211_MESHCONF_AWAKE_WINDOW,
-			cur_params.dot11MeshAwakeWindowDuration))
+			cur_params.dot11MeshAwakeWindowDuration) ||
+	    nla_put_u32(msg, NL80211_MESHCONF_PLINK_TIMEOUT,
+			cur_params.plink_timeout))
 		goto nla_put_failure;
 	nla_nest_end(msg, pinfoattr);
 	genlmsg_end(msg, hdr);
@@ -4616,6 +4618,7 @@ static const struct nla_policy nl80211_meshconf_params_policy[NL80211_MESHCONF_A
 	[NL80211_MESHCONF_HWMP_CONFIRMATION_INTERVAL] = { .type = NLA_U16 },
 	[NL80211_MESHCONF_POWER_MODE] = { .type = NLA_U32 },
 	[NL80211_MESHCONF_AWAKE_WINDOW] = { .type = NLA_U16 },
+	[NL80211_MESHCONF_PLINK_TIMEOUT] = { .type = NLA_U32 },
 };
 
 static const struct nla_policy
@@ -4753,6 +4756,9 @@ do {									    \
 	FILL_IN_MESH_PARAM_IF_SET(tb, cfg, dot11MeshAwakeWindowDuration,
 				  0, 65535, mask,
 				  NL80211_MESHCONF_AWAKE_WINDOW, nla_get_u16);
+	FILL_IN_MESH_PARAM_IF_SET(tb, cfg, plink_timeout, 1, 0xffffffff,
+				  mask, NL80211_MESHCONF_PLINK_TIMEOUT,
+				  nla_get_u32);
 	if (mask_out)
 		*mask_out = mask;