nl80211: Add support to configure TID specific retry configuration

This patch adds support to configure per TID retry configuration
through the NL80211_TID_CONFIG_ATTR_RETRY_SHORT and
NL80211_TID_CONFIG_ATTR_RETRY_LONG attributes. This TID specific
retry configuration will have more precedence than phy level
configuration.

Signed-off-by: Tamizh chelvam <tamizhr@codeaurora.org>
Link: https://lore.kernel.org/r/1579506687-18296-3-git-send-email-tamizhr@codeaurora.org
[rebase completely on top of my previous API changes]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -634,12 +634,15 @@ struct cfg80211_chan_def {
  * @mask: bitmap of attributes indicating which parameter changed,
  *	similar to &nl80211_tid_config_supp.
  * @noack: noack configuration value for the TID
+ * @retry_long: retry count value
+ * @retry_short: retry count value
  */
 struct cfg80211_tid_cfg {
 	bool config_override;
 	u8 tids;
 	u32 mask;
 	enum nl80211_tid_config noack;
+	u8 retry_long, retry_short;
 };
 
 /**
@@ -4644,6 +4647,8 @@ struct wiphy_iftype_akm_suites {
  *	supported by the driver for each vif
  * @tid_config_support.peer: bitmap of attributes (configurations)
  *	supported by the driver for each peer
+ * @tid_config_support.max_retry: maximum supported retry count for
+ *	long/short retry configuration
  */
 struct wiphy {
 	/* assign these fields before you register the wiphy */
@@ -4777,8 +4782,11 @@ struct wiphy {
 
 	struct {
 		u64 peer, vif;
+		u8 max_retry;
 	} tid_config_support;
 
+	u8 max_data_retry_count;
+
 	char priv[0] __aligned(NETDEV_ALIGN);
 };
 

include/uapi/linux/nl80211.h

@@ -4785,6 +4785,16 @@ enum nl80211_tid_config {
  * @NL80211_TID_CONFIG_ATTR_NOACK: Configure ack policy for the TID.
  *	specified in %NL80211_TID_CONFIG_ATTR_TID. see %enum nl80211_tid_config.
  *	Its type is u8.
+ * @NL80211_TID_CONFIG_ATTR_RETRY_SHORT: Number of retries used with data frame
+ *	transmission, user-space sets this configuration in
+ *	&NL80211_CMD_SET_TID_CONFIG. It is u8 type, min value is 1 and
+ *	the max value is advertised by the driver in this attribute on
+ *	output in wiphy capabilities.
+ * @NL80211_TID_CONFIG_ATTR_RETRY_LONG: Number of retries used with data frame
+ *	transmission, user-space sets this configuration in
+ *	&NL80211_CMD_SET_TID_CONFIG. Its type is u8, min value is 1 and
+ *	the max value is advertised by the driver in this attribute on
+ *	output in wiphy capabilities.
  */
 enum nl80211_tid_config_attr {
 	__NL80211_TID_CONFIG_ATTR_INVALID,
@@ -4794,6 +4804,8 @@ enum nl80211_tid_config_attr {
 	NL80211_TID_CONFIG_ATTR_OVERRIDE,
 	NL80211_TID_CONFIG_ATTR_TIDS,
 	NL80211_TID_CONFIG_ATTR_NOACK,
+	NL80211_TID_CONFIG_ATTR_RETRY_SHORT,
+	NL80211_TID_CONFIG_ATTR_RETRY_LONG,
 
 	/* keep last */
 	__NL80211_TID_CONFIG_ATTR_AFTER_LAST,

net/wireless/nl80211.c

@@ -336,6 +336,8 @@ nl80211_tid_config_attr_policy[NL80211_TID_CONFIG_ATTR_MAX + 1] = {
 	[NL80211_TID_CONFIG_ATTR_TIDS] = NLA_POLICY_RANGE(NLA_U16, 1, 0xff),
 	[NL80211_TID_CONFIG_ATTR_NOACK] =
 			NLA_POLICY_MAX(NLA_U8, NL80211_TID_CONFIG_DISABLE),
+	[NL80211_TID_CONFIG_ATTR_RETRY_SHORT] = NLA_POLICY_MIN(NLA_U8, 1),
+	[NL80211_TID_CONFIG_ATTR_RETRY_LONG] = NLA_POLICY_MIN(NLA_U8, 1),
 };
 
 const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
@@ -1985,6 +1987,14 @@ nl80211_put_tid_config_support(struct cfg80211_registered_device *rdev,
 			      NL80211_TID_CONFIG_ATTR_PAD))
 		goto fail;
 
+	/* for now we just use the same value ... makes more sense */
+	if (nla_put_u8(msg, NL80211_TID_CONFIG_ATTR_RETRY_SHORT,
+		       rdev->wiphy.tid_config_support.max_retry))
+		goto fail;
+	if (nla_put_u8(msg, NL80211_TID_CONFIG_ATTR_RETRY_LONG,
+		       rdev->wiphy.tid_config_support.max_retry))
+		goto fail;
+
 	nla_nest_end(msg, supp);
 
 	return 0;
@@ -14019,6 +14029,24 @@ static int parse_tid_conf(struct cfg80211_registered_device *rdev,
 			nla_get_u8(attrs[NL80211_TID_CONFIG_ATTR_NOACK]);
 	}
 
+	if (attrs[NL80211_TID_CONFIG_ATTR_RETRY_SHORT]) {
+		tid_conf->mask |= BIT(NL80211_TID_CONFIG_ATTR_RETRY_SHORT);
+		tid_conf->retry_short =
+			nla_get_u8(attrs[NL80211_TID_CONFIG_ATTR_RETRY_SHORT]);
+
+		if (tid_conf->retry_short > rdev->wiphy.max_data_retry_count)
+			return -EINVAL;
+	}
+
+	if (attrs[NL80211_TID_CONFIG_ATTR_RETRY_LONG]) {
+		tid_conf->mask |= BIT(NL80211_TID_CONFIG_ATTR_RETRY_LONG);
+		tid_conf->retry_long =
+			nla_get_u8(attrs[NL80211_TID_CONFIG_ATTR_RETRY_LONG]);
+
+		if (tid_conf->retry_long > rdev->wiphy.max_data_retry_count)
+			return -EINVAL;
+	}
+
 	if (peer)
 		mask = rdev->wiphy.tid_config_support.peer;
 	else