Add NL80211_CMD_AP_CH_SWITCH command which
triggers an AP channel switch process.
Usermode notified about channel switch complete
event with NL80211_CMD_CH_SWITCH_NOTIFY.
Usermode (hostapd) is responsible to update the
channel switch announcement IE in the beacon
prior and after the channel switch operation.
Signed-off-by: Victor Goldenshtein <victorg@xxxxxx>
---
include/linux/nl80211.h | 27 ++++++++++++++++++++
include/net/cfg80211.h | 36 +++++++++++++++++++++++++++
net/wireless/nl80211.c | 62 +++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 123 insertions(+), 2 deletions(-)
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index ee3336c..0538300 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -590,6 +590,17 @@
* the time passed since the beginning of the CAC is less than
* NL80211_DFS_MIN_CAC_TIME_MS, -EPERM is returned.
*
+ * @NL80211_CMD_AP_CH_SWITCH: Perform a channel switch in the driver (for
+ * AP/GO). Userspace daemon is responsible to update the CSA IE in the
+ * beacon prior and after the channel switch operation. Userspace notified
+ * about channel switch complete event with %NL80211_CMD_CH_SWITCH_NOTIFY.
+ * %NL80211_ATTR_WIPHY_FREQ is used to specify the new channel frequency.
+ * %NL80211_ATTR_CH_SWITCH_BLOCK_TX is used to specify that tx must be
+ * blocked on the current channel. %NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX
+ * is used to specify that tx must be blocked on the target channel.
+ * %NL80211_FREQ_ATTR_CH_SWITCH_COUNT to specify the number of TBTT's until
+ * the device switches to the target channel.
+ *
* @NL80211_CMD_MAX: highest used command number
* @__NL80211_CMD_AFTER_LAST: internal use
*/
@@ -742,6 +753,8 @@ enum nl80211_commands {
NL80211_CMD_DFS_ENABLE_TX,
+ NL80211_CMD_AP_CH_SWITCH,
+
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
@@ -1289,6 +1302,15 @@ enum nl80211_commands {
* the connection request from a station. nl80211_connect_failed_reason
* enum has different reasons of connection failure.
*
+ * @NL80211_ATTR_CH_SWITCH_COUNT: u32 attribute specifying the number of TBTT's
+ * until the channel switch event.
+ * @NL80211_ATTR_CH_SWITCH_BLOCK_TX: flag attribute specifying that transmission
+ * must be blocked on the current channel (before the channel switch
+ * operation).
+ * @NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX: flag attribute specifying that
+ * transmission must be blocked on the target channel after the channel
+ * switch operation, should be set if the target channel is DFS channel.
+ *
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
*/
@@ -1546,6 +1568,10 @@ enum nl80211_attrs {
NL80211_ATTR_CONN_FAILED_REASON,
+ NL80211_ATTR_CH_SWITCH_COUNT,
+ NL80211_ATTR_CH_SWITCH_BLOCK_TX,
+ NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
@@ -3056,6 +3082,7 @@ enum nl80211_feature_flags {
NL80211_FEATURE_CELL_BASE_REG_HINTS = 1 << 3,
NL80211_FEATURE_P2P_DEVICE_NEEDS_CHANNEL = 1 << 4,
NL80211_FEATURE_20MHZ_DFS = 1 << 5,
+ NL80211_FEATURE_AP_CH_SWITCH = 1 << 6,
};
/**
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index f2d4bde..ceff832 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -154,6 +154,36 @@ struct ieee80211_channel {
};
/**
+ * struct ieee80211_ap_ch_switch - holds the ap channel switch data
+ *
+ * The information provided in this structure is required for the ap channel
+ * switch operation.
+ *
+ * @timestamp: value in microseconds of the 64-bit Time Synchronization
+ * Function (TSF) timer when the frame containing the channel switch
+ * announcement was received. This is simply the rx.mactime parameter
+ * the driver passed into mac80211.
+ * @block_tx: Indicates whether transmission must be blocked before the
+ * scheduled channel switch, setting this flag will rise Channel Switch
+ * Mode bit in the AP CSA IE which means that all STAs in a BSS shall
+ * stop transmitting immediately.
+ * @post_switch_block_tx: Indicates whether the AP transmission must be blocked
+ * after the scheduled channel switch, this should be set if the target
+ * channel is DFS channel.
+ * @channel: the new channel to switch to
+ * @channel_type: the type of the new channel
+ * @count: the number of TBTT's until the channel switch event
+ */
+struct ieee80211_ap_ch_switch {
+ u64 timestamp;
+ bool block_tx;
+ bool post_switch_block_tx;
+ struct ieee80211_channel *channel;
+ enum nl80211_channel_type channel_type;
+ u8 count;
+};
+
+/**
* enum ieee80211_rate_flags - rate flags
*
* Hardware/specification flags for rates. These are structured
@@ -1633,6 +1663,8 @@ struct cfg80211_gtk_rekey_data {
* @start_radar_detection: Start radar detection in the driver.
*
* @dfs_en_tx: Enable tx after radar interference check.
+ *
+ * @ap_channel_switch: Perform AP channel switch.
*/
struct cfg80211_ops {
int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow);
@@ -1860,6 +1892,10 @@ struct cfg80211_ops {
int (*dfs_en_tx)(struct wiphy *wiphy, struct net_device *dev,
struct ieee80211_channel *chan);
+
+ int (*ap_channel_switch)(struct wiphy *wiphy,
+ struct net_device *dev,
+ struct ieee80211_ap_ch_switch *ap_ch_sw);
};
/*
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index be4e160..a40e81e 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -355,6 +355,9 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
[NL80211_ATTR_BG_SCAN_PERIOD] = { .type = NLA_U16 },
[NL80211_ATTR_WDEV] = { .type = NLA_U64 },
[NL80211_ATTR_USER_REG_HINT_TYPE] = { .type = NLA_U32 },
+ [NL80211_ATTR_CH_SWITCH_COUNT] = { .type = NLA_U32 },
+ [NL80211_ATTR_CH_SWITCH_BLOCK_TX] = { .type = NLA_FLAG },
+ [NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX] = { .type = NLA_FLAG },
};
/* policy for the key attributes */
@@ -4614,7 +4617,8 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
struct ieee80211_channel *chan;
enum nl80211_channel_type cac_type;
- if (!(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS))
+ if (!(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS) ||
+ !(rdev->wiphy.features & NL80211_FEATURE_AP_CH_SWITCH))
return -EOPNOTSUPP;
if (!info->attrs[NL80211_ATTR_WIPHY_FREQ] ||
@@ -4656,7 +4660,8 @@ static int nl80211_dfs_en_tx(struct sk_buff *skb, struct genl_info *info)
int freq;
if (!rdev->ops->dfs_en_tx ||
- !(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS))
+ !(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS) ||
+ !(rdev->wiphy.features & NL80211_FEATURE_AP_CH_SWITCH))
return -EOPNOTSUPP;
if (info->attrs[NL80211_ATTR_WIPHY_FREQ])
@@ -4677,6 +4682,51 @@ static int nl80211_dfs_en_tx(struct sk_buff *skb, struct genl_info *info)
return rdev->ops->dfs_en_tx(&rdev->wiphy, dev, chan);
}
+static int nl80211_ap_channel_switch(struct sk_buff *skb,
+ struct genl_info *info)
+{
+ struct cfg80211_registered_device *rdev = info->user_ptr[0];
+ struct net_device *dev = info->user_ptr[1];
+ u32 freq = 0;
+ struct ieee80211_ap_ch_switch ap_ch_sw;
+
+ if (!rdev->ops->ap_channel_switch)
+ return -EOPNOTSUPP;
+
+ if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
+ dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
+ return -EOPNOTSUPP;
+
+ if (!info->attrs[NL80211_ATTR_CH_SWITCH_COUNT] ||
+ !info->attrs[NL80211_ATTR_WIPHY_FREQ] ||
+ !info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE])
+ return -EINVAL;
+
+ memset(&ap_ch_sw, 0, sizeof(ap_ch_sw));
+
+ ap_ch_sw.channel_type =
+ nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
+ if ((ap_ch_sw.channel_type != NL80211_CHAN_HT20) &&
+ (ap_ch_sw.channel_type != NL80211_CHAN_NO_HT))
+ return -EOPNOTSUPP;
+
+ ap_ch_sw.count = nla_get_u32(info->attrs[NL80211_ATTR_CH_SWITCH_COUNT]);
+ freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]);
+
+ ap_ch_sw.channel = ieee80211_get_channel(&rdev->wiphy, freq);
+ if (!ap_ch_sw.channel ||
+ ap_ch_sw.channel->flags & IEEE80211_CHAN_DISABLED)
+ return -EINVAL;
+
+ if (info->attrs[NL80211_ATTR_CH_SWITCH_BLOCK_TX])
+ ap_ch_sw.block_tx = true;
+
+ if (info->attrs[NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX])
+ ap_ch_sw.post_switch_block_tx = true;
+
+ return rdev->ops->ap_channel_switch(&rdev->wiphy, dev, &ap_ch_sw);
+}
+
static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
u32 seq, int flags,
struct cfg80211_registered_device *rdev,
@@ -7641,6 +7691,14 @@ static struct genl_ops nl80211_ops[] = {
.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
NL80211_FLAG_NEED_RTNL,
},
+ {
+ .cmd = NL80211_CMD_AP_CH_SWITCH,
+ .doit = nl80211_ap_channel_switch,
+ .policy = nl80211_policy,
+ .flags = GENL_ADMIN_PERM,
+ .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+ NL80211_FLAG_NEED_RTNL,
+ },
};
static struct genl_multicast_group nl80211_mlme_mcgrp = {
--
1.7.5.4
--
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