cfg80211: add channel switch started notification
Add a new NL80211_CH_SWITCH_STARTED_NOTIFY message that can be sent to
the userspace when a channel switch process has started. This allows
userspace to take action, for instance, by requesting other interfaces
to switch channel as necessary.
This patch introduces a function that allows the drivers to send this
notification. It should be used when the driver starts processing a
channel switch initiated by a remote device (eg. when a STA receives a
CSA from the AP) and when it successfully starts a userspace-triggered
channel switch (eg. when hostapd triggers a channel swith in the AP).
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 5c3acd0..220d5f5 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4719,6 +4719,20 @@
void cfg80211_ch_switch_notify(struct net_device *dev,
struct cfg80211_chan_def *chandef);
+/*
+ * cfg80211_ch_switch_started_notify - notify channel switch start
+ * @dev: the device on which the channel switch started
+ * @chandef: the future channel definition
+ * @count: the number of TBTTs until the channel switch happens
+ *
+ * Inform the userspace about the channel switch that has just
+ * started, so that it can take appropriate actions (eg. starting
+ * channel switch on other vifs), if necessary.
+ */
+void cfg80211_ch_switch_started_notify(struct net_device *dev,
+ struct cfg80211_chan_def *chandef,
+ u8 count);
+
/**
* ieee80211_operating_class_to_band - convert operating class to band
*
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 9b3025e..3541634 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -645,6 +645,15 @@
* %NL80211_ATTR_IFINDEX is now on %NL80211_ATTR_WIPHY_FREQ and the
* attributes determining channel width.
*
+ * @NL80211_CMD_CH_SWITCH_STARTED_NOTIFY: Notify that a channel switch
+ * has been started on an interface, regardless of the initiator
+ * (ie. whether it was requested from a remote device or
+ * initiated on our own). It indicates that
+ * %NL80211_ATTR_IFINDEX will be on %NL80211_ATTR_WIPHY_FREQ
+ * after %NL80211_ATTR_CH_SWITCH_COUNT TBTT's. The userspace may
+ * decide to react to this indication by requesting other
+ * interfaces to change channel as well.
+ *
* @NL80211_CMD_START_P2P_DEVICE: Start the given P2P Device, identified by
* its %NL80211_ATTR_WDEV identifier. It must have been created with
* %NL80211_CMD_NEW_INTERFACE previously. After it has been started, the
@@ -930,6 +939,8 @@
NL80211_CMD_JOIN_OCB,
NL80211_CMD_LEAVE_OCB,
+ NL80211_CMD_CH_SWITCH_STARTED_NOTIFY,
+
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 24549cb..24fd292 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -11653,7 +11653,9 @@
static void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev,
struct net_device *netdev,
struct cfg80211_chan_def *chandef,
- gfp_t gfp)
+ gfp_t gfp,
+ enum nl80211_commands notif,
+ u8 count)
{
struct sk_buff *msg;
void *hdr;
@@ -11662,7 +11664,7 @@
if (!msg)
return;
- hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_CH_SWITCH_NOTIFY);
+ hdr = nl80211hdr_put(msg, 0, 0, 0, notif);
if (!hdr) {
nlmsg_free(msg);
return;
@@ -11674,6 +11676,10 @@
if (nl80211_send_chandef(msg, chandef))
goto nla_put_failure;
+ if ((notif == NL80211_CMD_CH_SWITCH_STARTED_NOTIFY) &&
+ (nla_put_u32(msg, NL80211_ATTR_CH_SWITCH_COUNT, count)))
+ goto nla_put_failure;
+
genlmsg_end(msg, hdr);
genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0,
@@ -11704,10 +11710,26 @@
wdev->chandef = *chandef;
wdev->preset_chandef = *chandef;
- nl80211_ch_switch_notify(rdev, dev, chandef, GFP_KERNEL);
+ nl80211_ch_switch_notify(rdev, dev, chandef, GFP_KERNEL,
+ NL80211_CMD_CH_SWITCH_NOTIFY, 0);
}
EXPORT_SYMBOL(cfg80211_ch_switch_notify);
+void cfg80211_ch_switch_started_notify(struct net_device *dev,
+ struct cfg80211_chan_def *chandef,
+ u8 count)
+{
+ struct wireless_dev *wdev = dev->ieee80211_ptr;
+ struct wiphy *wiphy = wdev->wiphy;
+ struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
+
+ trace_cfg80211_ch_switch_started_notify(dev, chandef);
+
+ nl80211_ch_switch_notify(rdev, dev, chandef, GFP_KERNEL,
+ NL80211_CMD_CH_SWITCH_STARTED_NOTIFY, count);
+}
+EXPORT_SYMBOL(cfg80211_ch_switch_started_notify);
+
void cfg80211_cqm_txe_notify(struct net_device *dev,
const u8 *peer, u32 num_packets,
u32 rate, u32 intvl, gfp_t gfp)
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 277a85d..6e25370 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2355,6 +2355,22 @@
NETDEV_PR_ARG, CHAN_DEF_PR_ARG)
);
+TRACE_EVENT(cfg80211_ch_switch_started_notify,
+ TP_PROTO(struct net_device *netdev,
+ struct cfg80211_chan_def *chandef),
+ TP_ARGS(netdev, chandef),
+ TP_STRUCT__entry(
+ NETDEV_ENTRY
+ CHAN_DEF_ENTRY
+ ),
+ TP_fast_assign(
+ NETDEV_ASSIGN;
+ CHAN_DEF_ASSIGN(chandef);
+ ),
+ TP_printk(NETDEV_PR_FMT ", " CHAN_DEF_PR_FMT,
+ NETDEV_PR_ARG, CHAN_DEF_PR_ARG)
+);
+
TRACE_EVENT(cfg80211_radar_event,
TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef),
TP_ARGS(wiphy, chandef),
