[v3,04/12] nl80211: support setting S1G short beacon period

Commit Message

Kieran Frewen Sept. 6, 2022, 4:48 a.m. UTC

With the kernel able to send both short and long S1G beacons, include
the ability for setting the short beacon period.

Signed-off-by: Kieran Frewen <[e-mail]>
---
 include/uapi/linux/nl80211.h | 7 +++++++
 net/wireless/nl80211.c       | 4 ++++
 2 files changed, 11 insertions(+)

Comments

Johannes Berg Sept. 6, 2022, 9:42 a.m. UTC | #1

On Tue, 2022-09-06 at 16:48 +1200, Kieran Frewen wrote:
> 
> @@ -805,6 +805,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
>  	[NL80211_ATTR_MLD_ADDR] = NLA_POLICY_EXACT_LEN(ETH_ALEN),
>  	[NL80211_ATTR_MLO_SUPPORT] = { .type = NLA_FLAG },
>  	[NL80211_ATTR_MAX_NUM_AKM_SUITES] = { .type = NLA_REJECT },
> +	[NL80211_ATTR_SHORT_BEACON_PERIOD] = { .type = NLA_U16 },

You probably want _some_ kind of range validation here, like "don't set
it to zero" at least?

> +	if (info->attrs[NL80211_ATTR_SHORT_BEACON_PERIOD])
> +		params->short_beacon_period =
> +			nla_get_u32(info->attrs[NL80211_ATTR_SHORT_BEACON_PERIOD]);
> 

And maybe it should be < the long beacon period?

Actually the mac80211 code makes it sound like what you really should
have is a "long beacon period" or something, so that every N beacons you
send a long one?

Or are these really completely independent? It feels like probably the
intention would be to have a (short) beacon period, and then every N
beacons you send a long one?

johannes

Patch

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index ffb7c573e299..7daa2ce1cb57 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2741,6 +2741,9 @@  enum nl80211_commands {
  *	When used with %NL80211_CMD_FRAME_TX_STATUS, indicates the ack RX
  *	timestamp. When used with %NL80211_CMD_FRAME RX notification, indicates
  *	the incoming frame RX timestamp.
+ *
+ * @NL80211_ATTR_SHORT_BEACON_PERIOD: S1G short beacon period in TUs.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3269,6 +3272,8 @@  enum nl80211_attrs {
 	NL80211_ATTR_TX_HW_TIMESTAMP,
 	NL80211_ATTR_RX_HW_TIMESTAMP,
 
+	NL80211_ATTR_SHORT_BEACON_PERIOD,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -4951,6 +4956,7 @@  enum nl80211_bss_scan_width {
  *	using the nesting index as the antenna number.
  * @NL80211_BSS_FREQUENCY_OFFSET: frequency offset in KHz
  * @NL80211_BSS_MLO_LINK_ID: MLO link ID of the BSS (u8).
+ * @NL80211_BSS_SHORT_BEACON_PERIOD: S1G short beacon period in TUs
  * @__NL80211_BSS_AFTER_LAST: internal
  * @NL80211_BSS_MAX: highest BSS attribute
  */
@@ -4977,6 +4983,7 @@  enum nl80211_bss {
 	NL80211_BSS_CHAIN_SIGNAL,
 	NL80211_BSS_FREQUENCY_OFFSET,
 	NL80211_BSS_MLO_LINK_ID,
+	NL80211_BSS_SHORT_BEACON_PERIOD,
 
 	/* keep last */
 	__NL80211_BSS_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2705e3ee8fc4..5e9aaa8c0d7d 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -805,6 +805,7 @@  static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_MLD_ADDR] = NLA_POLICY_EXACT_LEN(ETH_ALEN),
 	[NL80211_ATTR_MLO_SUPPORT] = { .type = NLA_FLAG },
 	[NL80211_ATTR_MAX_NUM_AKM_SUITES] = { .type = NLA_REJECT },
+	[NL80211_ATTR_SHORT_BEACON_PERIOD] = { .type = NLA_U16 },
 };
 
 /* policy for the key attributes */
@@ -5711,6 +5712,9 @@  static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 		nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
 	params->dtim_period =
 		nla_get_u32(info->attrs[NL80211_ATTR_DTIM_PERIOD]);
+	if (info->attrs[NL80211_ATTR_SHORT_BEACON_PERIOD])
+		params->short_beacon_period =
+			nla_get_u32(info->attrs[NL80211_ATTR_SHORT_BEACON_PERIOD]);
 
 	err = cfg80211_validate_beacon_int(rdev, dev->ieee80211_ptr->iftype,
 					   params->beacon_interval);