diff mbox

[4/7] cfg80211: Add support to notify station's rssi level crossing

Message ID 1528886747-26342-5-git-send-email-tamizhr@codeaurora.org (mailing list archive)
State Changes Requested
Delegated to: Johannes Berg
Headers show

Commit Message

Tamizh chelvam June 13, 2018, 10:45 a.m. UTC
Add cfg80211_sta_mon_rssi_notify api to update user space upon
crossing the configured rssi threshold of a station.
NL80211_CMD_NOTIFY_STA_MON introduced to send this event to
userspace along with NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
NL80211_ATTR_MAC and NL80211_ATTR_STA_MON_RSSI_LEVEL info.
Userspace application can make a decision depends on this
notification.

Signed-off-by: Tamizh chelvam <tamizhr@codeaurora.org>
---
 include/net/cfg80211.h       |   16 +++++++
 include/uapi/linux/nl80211.h |    1 +
 net/wireless/nl80211.c       |   98 ++++++++++++++++++++++++++++++++++++++++++
 net/wireless/trace.h         |   22 ++++++++++
 4 files changed, 137 insertions(+)

Comments

Johannes Berg June 29, 2018, 9:35 a.m. UTC | #1
On Wed, 2018-06-13 at 16:15 +0530, Tamizh chelvam wrote:
> Add cfg80211_sta_mon_rssi_notify api to update user space upon
> crossing the configured rssi threshold of a station.
> NL80211_CMD_NOTIFY_STA_MON introduced to send this event to
> userspace along with NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
> NL80211_ATTR_MAC and NL80211_ATTR_STA_MON_RSSI_LEVEL info.
> Userspace application can make a decision depends on this
> notification.

I guess you should also combine this with patch 2, it's a bit weird to
only have one side and not be able to use it in one patch, and both
aren't all that big.


> --- a/include/uapi/linux/nl80211.h
> +++ b/include/uapi/linux/nl80211.h
> @@ -1249,6 +1249,7 @@ enum nl80211_commands {
>  	NL80211_CMD_CONTROL_PORT_FRAME,
>  
>  	NL80211_CMD_SET_STA_MON,
> +	NL80211_CMD_NOTIFY_STA_MON,

Missing documentation - but again, why not unify it with the existing
event? Or can't we because that might confuse older applications?
Perhaps anyway we should unicast these notifications? Not sure though,
perhaps one app could set them up and the other might care?

> +static struct sk_buff *cfg80211_prepare_sta_mon(struct net_device *dev,
> +						const char *mac, gfp_t gfp)
> +{
> +	struct wireless_dev *wdev = dev->ieee80211_ptr;
> +	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
> +	struct sk_buff *msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
> +	void **cb;
> +
> +	if (!msg)
> +		return NULL;
> +
> +	cb = (void **)msg->cb;

Uh, what's that? Please use a structure.

> +	cb[0] = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_NOTIFY_STA_MON);
> 
[...]
> +
> +	cb[1] = nla_nest_start(msg, NL80211_ATTR_STA_MON);
> +	if (!cb[1])
> +		goto nla_put_failure;
> +
> +	cb[2] = rdev;

Yeah, definitely use a struct instead of three magic array indices.

> +
> +	msg = cfg80211_prepare_sta_mon(dev, peer, gfp);
> +	if (!msg)
> +		return;
> +
> +	if (nla_put_u32(msg, NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
> +			rssi_event))
> +		goto nla_put_failure;
> +
> +	if (rssi_level && nla_put_s32(msg, NL80211_ATTR_STA_MON_RSSI_LEVEL,
> +				      rssi_level))
> +		goto nla_put_failure;
> +
> +	cfg80211_send_sta_mon(msg, gfp);

In fact, perhaps better to have something like

struct nl80211_sta_mon_prep {
	struct sk_buff *skb;
	....
};

struct nl80211_sta_mon_prep prep;

if (cfg80211_prepare_sta_mon(&prep))
	return;
...
cfg80211_send_sta_mon(&prep, gfp);

or so?

johannes
Tamizh chelvam July 4, 2018, 6:13 a.m. UTC | #2
On 2018-06-29 15:05, Johannes Berg wrote:
> On Wed, 2018-06-13 at 16:15 +0530, Tamizh chelvam wrote:
>> Add cfg80211_sta_mon_rssi_notify api to update user space upon
>> crossing the configured rssi threshold of a station.
>> NL80211_CMD_NOTIFY_STA_MON introduced to send this event to
>> userspace along with NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
>> NL80211_ATTR_MAC and NL80211_ATTR_STA_MON_RSSI_LEVEL info.
>> Userspace application can make a decision depends on this
>> notification.
> 
> I guess you should also combine this with patch 2, it's a bit weird to
> only have one side and not be able to use it in one patch, and both
> aren't all that big.
Sure
> 
> 
>> --- a/include/uapi/linux/nl80211.h
>> +++ b/include/uapi/linux/nl80211.h
>> @@ -1249,6 +1249,7 @@ enum nl80211_commands {
>>  	NL80211_CMD_CONTROL_PORT_FRAME,
>> 
>>  	NL80211_CMD_SET_STA_MON,
>> +	NL80211_CMD_NOTIFY_STA_MON,
> 
> Missing documentation - but again, why not unify it with the existing
> event? Or can't we because that might confuse older applications?
> Perhaps anyway we should unicast these notifications? Not sure though,
> perhaps one app could set them up and the other might care?
> 
This new command introduced as per the previous discussion
https://patchwork.kernel.org/patch/10168685/
https://patchwork.kernel.org/patch/10240697/

Is my understanding correct ?

>> +static struct sk_buff *cfg80211_prepare_sta_mon(struct net_device 
>> *dev,
>> +						const char *mac, gfp_t gfp)
>> +{
>> +	struct wireless_dev *wdev = dev->ieee80211_ptr;
>> +	struct cfg80211_registered_device *rdev = 
>> wiphy_to_rdev(wdev->wiphy);
>> +	struct sk_buff *msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
>> +	void **cb;
>> +
>> +	if (!msg)
>> +		return NULL;
>> +
>> +	cb = (void **)msg->cb;
> 
> Uh, what's that? Please use a structure.

I just referred this code from cfg80211_prepare_cqm. Do you want me to 
change this to struct based?
> 
>> +	cb[0] = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_NOTIFY_STA_MON);
>> 
> [...]
>> +
>> +	cb[1] = nla_nest_start(msg, NL80211_ATTR_STA_MON);
>> +	if (!cb[1])
>> +		goto nla_put_failure;
>> +
>> +	cb[2] = rdev;
> 
> Yeah, definitely use a struct instead of three magic array indices.
> 
>> +
>> +	msg = cfg80211_prepare_sta_mon(dev, peer, gfp);
>> +	if (!msg)
>> +		return;
>> +
>> +	if (nla_put_u32(msg, NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
>> +			rssi_event))
>> +		goto nla_put_failure;
>> +
>> +	if (rssi_level && nla_put_s32(msg, NL80211_ATTR_STA_MON_RSSI_LEVEL,
>> +				      rssi_level))
>> +		goto nla_put_failure;
>> +
>> +	cfg80211_send_sta_mon(msg, gfp);
> 
> In fact, perhaps better to have something like
> 
> struct nl80211_sta_mon_prep {
> 	struct sk_buff *skb;
> 	....
> };
> 
> struct nl80211_sta_mon_prep prep;
> 
> if (cfg80211_prepare_sta_mon(&prep))
> 	return;
> ...
> cfg80211_send_sta_mon(&prep, gfp);
> 
> or so?

Tamizh.
Johannes Berg July 6, 2018, 11:39 a.m. UTC | #3
On Wed, 2018-07-04 at 11:43 +0530, Tamizh chelvam wrote:

> > > --- a/include/uapi/linux/nl80211.h
> > > +++ b/include/uapi/linux/nl80211.h
> > > @@ -1249,6 +1249,7 @@ enum nl80211_commands {
> > >  	NL80211_CMD_CONTROL_PORT_FRAME,
> > > 
> > >  	NL80211_CMD_SET_STA_MON,
> > > +	NL80211_CMD_NOTIFY_STA_MON,
> > 
> > Missing documentation - but again, why not unify it with the existing
> > event? Or can't we because that might confuse older applications?
> > Perhaps anyway we should unicast these notifications? Not sure though,
> > perhaps one app could set them up and the other might care?
> > 
> 
> This new command introduced as per the previous discussion
> https://patchwork.kernel.org/patch/10168685/
> https://patchwork.kernel.org/patch/10240697/
> 
> Is my understanding correct ?

I guess you're right. To my defense, this was like almost half a year
ago :)

> I just referred this code from cfg80211_prepare_cqm. Do you want me to 
> change this to struct based?

Please, I guess we can fix up cqm too later.

johannes
Tamizh chelvam July 11, 2018, 5:55 a.m. UTC | #4
On 2018-07-06 17:09, Johannes Berg wrote:
> On Wed, 2018-07-04 at 11:43 +0530, Tamizh chelvam wrote:
> 
>> > > --- a/include/uapi/linux/nl80211.h
>> > > +++ b/include/uapi/linux/nl80211.h
>> > > @@ -1249,6 +1249,7 @@ enum nl80211_commands {
>> > >  	NL80211_CMD_CONTROL_PORT_FRAME,
>> > >
>> > >  	NL80211_CMD_SET_STA_MON,
>> > > +	NL80211_CMD_NOTIFY_STA_MON,
>> >
>> > Missing documentation - but again, why not unify it with the existing
>> > event? Or can't we because that might confuse older applications?
>> > Perhaps anyway we should unicast these notifications? Not sure though,
>> > perhaps one app could set them up and the other might care?
>> >
>> 
>> This new command introduced as per the previous discussion
>> https://patchwork.kernel.org/patch/10168685/
>> https://patchwork.kernel.org/patch/10240697/
>> 
>> Is my understanding correct ?
> 
> I guess you're right. To my defense, this was like almost half a year
> ago :)
Yeah;)
> 
>> I just referred this code from cfg80211_prepare_cqm. Do you want me to
>> change this to struct based?
> 
> Please, I guess we can fix up cqm too later.
> 
Sure, I'll fix it in the next version.

Thanks,
Tamizh.
diff mbox

Patch

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 584697b..7dcf9b9 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5916,6 +5916,22 @@  void cfg80211_cqm_txe_notify(struct net_device *dev, const u8 *peer,
 void cfg80211_cqm_beacon_loss_notify(struct net_device *dev, gfp_t gfp);
 
 /**
+ * cfg80211_sta_mon_rssi_notify - Station's rssi out of range event
+ * @dev: network device
+ * @peer: Station'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 rssi threshold reached event
+ * occurs for a station.
+ */
+void
+cfg80211_sta_mon_rssi_notify(struct net_device *dev, const u8 *peer,
+		enum nl80211_sta_mon_rssi_threshold_event rssi_event,
+		s32 rssi_level, gfp_t gfp);
+
+/**
  * cfg80211_radar_event - radar detection event
  * @wiphy: the wiphy
  * @chandef: chandef for the current channel
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index f13ad07..9d47ee6 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1249,6 +1249,7 @@  enum nl80211_commands {
 	NL80211_CMD_CONTROL_PORT_FRAME,
 
 	NL80211_CMD_SET_STA_MON,
+	NL80211_CMD_NOTIFY_STA_MON,
 
 	/* add new commands above here */
 
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 587a5cb1..021e55a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -15364,6 +15364,104 @@  void cfg80211_pmksa_candidate_notify(struct net_device *dev, int index,
 }
 EXPORT_SYMBOL(cfg80211_pmksa_candidate_notify);
 
+static struct sk_buff *cfg80211_prepare_sta_mon(struct net_device *dev,
+						const char *mac, gfp_t gfp)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	struct sk_buff *msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
+	void **cb;
+
+	if (!msg)
+		return NULL;
+
+	cb = (void **)msg->cb;
+
+	cb[0] = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_NOTIFY_STA_MON);
+	if (!cb[0]) {
+		nlmsg_free(msg);
+		return NULL;
+	}
+
+	if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
+	    nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex))
+		goto nla_put_failure;
+
+	if (nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, mac))
+		goto nla_put_failure;
+
+	cb[1] = nla_nest_start(msg, NL80211_ATTR_STA_MON);
+	if (!cb[1])
+		goto nla_put_failure;
+
+	cb[2] = rdev;
+
+	return msg;
+nla_put_failure:
+	nlmsg_free(msg);
+	return NULL;
+}
+
+static void cfg80211_send_sta_mon(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_MLME, gfp);
+}
+
+void cfg80211_sta_mon_rssi_notify(struct net_device *dev, const u8 *peer,
+		enum nl80211_sta_mon_rssi_threshold_event rssi_event,
+		s32 rssi_level, gfp_t gfp)
+{
+	struct sk_buff *msg;
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_rssi_config *rssi_config;
+
+	if (WARN_ON(!peer))
+		return;
+
+	if (WARN_ON(rssi_event != NL80211_STA_MON_RSSI_THRESHOLD_EVENT_LOW &&
+		    rssi_event != NL80211_STA_MON_RSSI_THRESHOLD_EVENT_HIGH))
+		return;
+
+	trace_cfg80211_sta_mon_rssi_notify(dev, peer, rssi_event, rssi_level);
+
+	list_for_each_entry(rssi_config, &wdev->rssi_config_list, list) {
+		if (!memcmp(rssi_config->addr, peer, ETH_ALEN)) {
+			wdev->rssi_config = rssi_config;
+			wdev->rssi_config->last_rssi_event_value = rssi_level;
+			break;
+		}
+	}
+
+	msg = cfg80211_prepare_sta_mon(dev, peer, gfp);
+	if (!msg)
+		return;
+
+	if (nla_put_u32(msg, NL80211_ATTR_STA_MON_RSSI_THRESHOLD_EVENT,
+			rssi_event))
+		goto nla_put_failure;
+
+	if (rssi_level && nla_put_s32(msg, NL80211_ATTR_STA_MON_RSSI_LEVEL,
+				      rssi_level))
+		goto nla_put_failure;
+
+	cfg80211_send_sta_mon(msg, gfp);
+
+	return;
+
+nla_put_failure:
+	nlmsg_free(msg);
+}
+EXPORT_SYMBOL(cfg80211_sta_mon_rssi_notify);
+
 static void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev,
 				     struct net_device *netdev,
 				     struct cfg80211_chan_def *chandef,
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 361ec08..5454c57 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -3282,6 +3282,28 @@ 
 		  WIPHY_PR_ARG, NETDEV_PR_ARG, MAC_PR_ARG(peer),
 		  __entry->rssi_thold, __entry->rssi_hyst)
 );
+TRACE_EVENT(cfg80211_sta_mon_rssi_notify,
+	TP_PROTO(struct net_device *netdev, const u8 *peer,
+		 enum nl80211_sta_mon_rssi_threshold_event rssi_event,
+		 s32 rssi_level),
+	TP_ARGS(netdev, peer, rssi_event, rssi_level),
+	TP_STRUCT__entry(
+		NETDEV_ENTRY
+		MAC_ENTRY(peer)
+		__field(enum nl80211_sta_mon_rssi_threshold_event, rssi_event)
+		__field(s32, rssi_level)
+	),
+	TP_fast_assign(
+		NETDEV_ASSIGN;
+		MAC_ASSIGN(peer, peer);
+		__entry->rssi_event = rssi_event;
+		__entry->rssi_level = rssi_level;
+	),
+	TP_printk(NETDEV_PR_FMT ", peer: " MAC_PR_FMT
+		  ", rssi event: %d, rssi : %d",
+		  NETDEV_PR_ARG, MAC_PR_ARG(peer),
+		  __entry->rssi_event, __entry->rssi_level)
+);
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH