diff mbox

[PATCHv4,1/3] cfg80211: enable setting cqm rssi config for AP mode

Message ID 1519544998-2621-2-git-send-email-tamizhr@codeaurora.org (mailing list archive)
State Changes Requested
Delegated to: Johannes Berg
Headers show

Commit Message

Tamizh chelvam Feb. 25, 2018, 7:49 a.m. UTC 
From: Tamizh chelvam <tamizhr@codeaurora.org>

This patch extend cqm rssi config and notifier feature to AP mode
by introducing NL80211_EXT_FEATURE_AP_STA_CQM_RSSI_CONFIG ext
feature bit. And this patch introduces NL80211_MCGRP_AP_STA_CQM
for notifying station's low/high rssi event to userspace application.

Signed-off-by: Tamizh chelvam <tamizhr@codeaurora.org>
---
 include/net/cfg80211.h       |   15 +++++++++
 include/uapi/linux/nl80211.h |    6 ++++
 net/wireless/nl80211.c       |   71 ++++++++++++++++++++++++++++++++++++------
 3 files changed, 82 insertions(+), 10 deletions(-)

Comments

Johannes Berg March 23, 2018, 1:27 p.m. UTC | #1 
On Sun, 2018-02-25 at 13:19 +0530, Tamizh chelvam wrote:
> From: Tamizh chelvam <tamizhr@codeaurora.org>
> 
> This patch extend cqm rssi config and notifier feature to AP mode
> by introducing NL80211_EXT_FEATURE_AP_STA_CQM_RSSI_CONFIG ext
> feature bit. And this patch introduces NL80211_MCGRP_AP_STA_CQM
> for notifying station's low/high rssi event to userspace application.

So, I guess I can sort of see how this could be useful.

However, is it really best in this current form?

For example, it seems trivial to imagine that one might want to have
different thresholds for different stations, and nothing in the current
implementation would prevent that, just the CQM API isn't very suited
to that.

There was also an extension to CQM to support different levels - not
sure where that ended up, but we should take that into account I guess.


Overall, I'm still not really convinced CQM is the right approach here.

One thing I could even imagine would be to just not have this
capability at all, but build it into a little BPF program you install.
I had - and still want to revive - the code to insert a "programming
point" into the wireless stack, and one could then easily build a hash
table of TAs vs. signal strength in BPF code.

We may not want to go that far, but I think the current approach is too
short-sighted. This might solve a specific problem today, but I don't
think it'll serve us well into the future if we don't make it more
flexible.

johannes
diff mbox

Patch

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 56e905c..d19fd5c 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5706,6 +5706,21 @@  void cfg80211_cqm_rssi_notify(struct net_device *dev,
 			      s32 rssi_level, gfp_t gfp);
 
 /**
+ * cfg80211_ap_sta_cqm_rssi_notify - CQM rssi event for connected stations
+ * @dev: network device
+ * @mac: peer's MAC address
+ * @rssi_event: the triggered RSSI event
+ * @rssi_level: new RSSI level value or 0 if not available
+ * @gfp: context flags
+ *
+ * This function is called when a configured connection quality monitoring
+ * rssi threshold reached event occurs for a station.
+ */
+void cfg80211_ap_sta_cqm_rssi_notify(struct net_device *dev, const u8 *mac,
+		enum nl80211_cqm_rssi_threshold_event rssi_event,
+		s32 rssi_level, gfp_t gfp);
+
+/**
  * cfg80211_cqm_pktloss_notify - notify userspace about packetloss to peer
  * @dev: network device
  * @peer: peer's MAC address
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index c13c843..81a60dc 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -49,6 +49,7 @@ 
 #define NL80211_MULTICAST_GROUP_MLME		"mlme"
 #define NL80211_MULTICAST_GROUP_VENDOR		"vendor"
 #define NL80211_MULTICAST_GROUP_NAN		"nan"
+#define NL80211_MULTICAST_GROUP_AP_STA_CQM	"apstacqm"
 #define NL80211_MULTICAST_GROUP_TESTMODE	"testmode"
 
 /**
@@ -4999,6 +5000,10 @@  enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_LOW_SPAN_SCAN: Driver supports low span scan.
  * @NL80211_EXT_FEATURE_LOW_POWER_SCAN: Driver supports low power scan.
  * @NL80211_EXT_FEATURE_HIGH_ACCURACY_SCAN: Driver supports high accuracy scan.
+ * @NL80211_EXT_FEATURE_AP_STA_CQM_RSSI_CONFIG: With this driver will accept
+ *	%NL80211_ATTR_CQM_RSSI_THOLD and %NL80211_ATTR_CQM_RSSI_HYST attributes
+ *	for AP/AP_VLAN/P2P_GO interface to monitor rssi values of connected
+ *	client.
  *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
@@ -5029,6 +5034,7 @@  enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_LOW_SPAN_SCAN,
 	NL80211_EXT_FEATURE_LOW_POWER_SCAN,
 	NL80211_EXT_FEATURE_HIGH_ACCURACY_SCAN,
+	NL80211_EXT_FEATURE_AP_STA_CQM_RSSI_CONFIG,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index a910150..0ece819 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -44,6 +44,7 @@  enum nl80211_multicast_groups {
 	NL80211_MCGRP_MLME,
 	NL80211_MCGRP_VENDOR,
 	NL80211_MCGRP_NAN,
+	NL80211_MCGRP_AP_STA_CQM,
 	NL80211_MCGRP_TESTMODE /* keep last - ifdef! */
 };
 
@@ -54,6 +55,8 @@  enum nl80211_multicast_groups {
 	[NL80211_MCGRP_MLME] = { .name = NL80211_MULTICAST_GROUP_MLME },
 	[NL80211_MCGRP_VENDOR] = { .name = NL80211_MULTICAST_GROUP_VENDOR },
 	[NL80211_MCGRP_NAN] = { .name = NL80211_MULTICAST_GROUP_NAN },
+	[NL80211_MCGRP_AP_STA_CQM] = {
+				.name = NL80211_MULTICAST_GROUP_AP_STA_CQM },
 #ifdef CONFIG_NL80211_TESTMODE
 	[NL80211_MCGRP_TESTMODE] = { .name = NL80211_MULTICAST_GROUP_TESTMODE }
 #endif
@@ -9905,8 +9908,13 @@  static int nl80211_set_cqm_rssi(struct genl_info *info,
 		prev = thresholds[i];
 	}
 
-	if (wdev->iftype != NL80211_IFTYPE_STATION &&
-	    wdev->iftype != NL80211_IFTYPE_P2P_CLIENT)
+	if ((wdev->iftype != NL80211_IFTYPE_STATION &&
+	     wdev->iftype != NL80211_IFTYPE_P2P_CLIENT) &&
+	    ((wdev->iftype == NL80211_IFTYPE_AP ||
+	      wdev->iftype == NL80211_IFTYPE_AP_VLAN ||
+	      wdev->iftype == NL80211_IFTYPE_P2P_GO) &&
+	     !wiphy_ext_feature_isset(&rdev->wiphy,
+				NL80211_EXT_FEATURE_AP_STA_CQM_RSSI_CONFIG)))
 		return -EOPNOTSUPP;
 
 	wdev_lock(wdev);
@@ -14587,9 +14595,24 @@  static void cfg80211_send_cqm(struct sk_buff *msg, gfp_t gfp)
 				NL80211_MCGRP_MLME, gfp);
 }
 
-void cfg80211_cqm_rssi_notify(struct net_device *dev,
-			      enum nl80211_cqm_rssi_threshold_event rssi_event,
-			      s32 rssi_level, gfp_t gfp)
+static void cfg80211_send_ap_sta_cqm(struct sk_buff *msg, gfp_t gfp)
+{
+	void **cb = (void **)msg->cb;
+	struct cfg80211_registered_device *rdev = cb[2];
+
+	nla_nest_end(msg, cb[1]);
+	genlmsg_end(msg, cb[0]);
+
+	memset(msg->cb, 0, sizeof(msg->cb));
+
+	genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0,
+				NL80211_MCGRP_AP_STA_CQM, gfp);
+}
+
+static struct sk_buff *cfg80211_cqm_rssi_prepare(struct net_device *dev,
+			const u8 *mac,
+			enum nl80211_cqm_rssi_threshold_event rssi_event,
+			s32 rssi_level, gfp_t gfp)
 {
 	struct sk_buff *msg;
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
@@ -14599,7 +14622,7 @@  void cfg80211_cqm_rssi_notify(struct net_device *dev,
 
 	if (WARN_ON(rssi_event != NL80211_CQM_RSSI_THRESHOLD_EVENT_LOW &&
 		    rssi_event != NL80211_CQM_RSSI_THRESHOLD_EVENT_HIGH))
-		return;
+		return NULL;
 
 	if (wdev->cqm_config) {
 		wdev->cqm_config->last_rssi_event_value = rssi_level;
@@ -14612,7 +14635,7 @@  void cfg80211_cqm_rssi_notify(struct net_device *dev,
 
 	msg = cfg80211_prepare_cqm(dev, NULL, gfp);
 	if (!msg)
-		return;
+		return NULL;
 
 	if (nla_put_u32(msg, NL80211_ATTR_CQM_RSSI_THRESHOLD_EVENT,
 			rssi_event))
@@ -14622,15 +14645,43 @@  void cfg80211_cqm_rssi_notify(struct net_device *dev,
 				      rssi_level))
 		goto nla_put_failure;
 
-	cfg80211_send_cqm(msg, gfp);
-
-	return;
+	return msg;
 
  nla_put_failure:
 	nlmsg_free(msg);
+	return NULL;
+}
+
+void cfg80211_cqm_rssi_notify(struct net_device *dev,
+			      enum nl80211_cqm_rssi_threshold_event rssi_event,
+			      s32 rssi_level, gfp_t gfp)
+{
+	struct sk_buff *msg;
+
+	msg = cfg80211_cqm_rssi_prepare(dev, NULL, rssi_event, rssi_level,
+					gfp);
+	if (!msg)
+		return;
+	cfg80211_send_cqm(msg, gfp);
+
+	return;
 }
 EXPORT_SYMBOL(cfg80211_cqm_rssi_notify);
 
+void cfg80211_ap_sta_cqm_rssi_notify(struct net_device *dev, const u8 *mac,
+			  enum nl80211_cqm_rssi_threshold_event rssi_event,
+			  s32 rssi_level, gfp_t gfp)
+{
+	struct sk_buff *msg;
+
+	msg = cfg80211_cqm_rssi_prepare(dev, mac, rssi_event, rssi_level,
+					gfp);
+	if (!msg)
+		return;
+	cfg80211_send_ap_sta_cqm(msg, gfp);
+}
+EXPORT_SYMBOL(cfg80211_ap_sta_cqm_rssi_notify);
+
 void cfg80211_cqm_txe_notify(struct net_device *dev,
 			     const u8 *peer, u32 num_packets,
 			     u32 rate, u32 intvl, gfp_t gfp)