rtlwifi: support accurate nullfunc frame tx ack report

In order to realize the keep-alive mechanism in mac80211 stack, reporting
accurate tx ack status for nullfunc frame is added in this commit.

If current frame is nullfunc frame, we ask firmware to report by filling
TX report bit in TX descriptor. After this frame DMA done, TX interrupt is
triggered but TX status is unknown at this moment, so enqueue this skb
into tx_report->queue. Finally, C2H report will be received if the frame
is transmitted successfully or retried over, and then we report to mac80211
with IEEE80211_TX_STAT_ACK flag only if it's successful. Otherwise, if
failure or timeout (one second), we report to mac80211 without this flag.
Signed-off-by: Tzu-En Huang <tehuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtlwifi/base.c

@@ -574,6 +574,7 @@ int rtl_init_core(struct ieee80211_hw *hw)
 	INIT_LIST_HEAD(&rtlpriv->entry_list);
 	INIT_LIST_HEAD(&rtlpriv->c2hcmd_list);
 	INIT_LIST_HEAD(&rtlpriv->scan_list.list);
+	skb_queue_head_init(&rtlpriv->tx_report.queue);
 
 	rtlmac->link_state = MAC80211_NOLINK;
 
@@ -585,11 +586,14 @@ int rtl_init_core(struct ieee80211_hw *hw)
 EXPORT_SYMBOL_GPL(rtl_init_core);
 
 static void rtl_free_entries_from_scan_list(struct ieee80211_hw *hw);
+static void rtl_free_entries_from_ack_queue(struct ieee80211_hw *hw,
+					    bool timeout);
 
 void rtl_deinit_core(struct ieee80211_hw *hw)
 {
 	rtl_c2hcmd_launcher(hw, 0);
 	rtl_free_entries_from_scan_list(hw);
+	rtl_free_entries_from_ack_queue(hw, false);
 }
 EXPORT_SYMBOL_GPL(rtl_deinit_core);
 
@@ -1575,22 +1579,52 @@ u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx,
 }
 EXPORT_SYMBOL_GPL(rtl_is_special_data);
 
+void rtl_tx_ackqueue(struct ieee80211_hw *hw, struct sk_buff *skb)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	struct rtl_tx_report *tx_report = &rtlpriv->tx_report;
+
+	__skb_queue_tail(&tx_report->queue, skb);
+}
+EXPORT_SYMBOL_GPL(rtl_tx_ackqueue);
+
+static void rtl_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb,
+			  bool ack)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	struct ieee80211_tx_info *info;
+
+	info = IEEE80211_SKB_CB(skb);
+	ieee80211_tx_info_clear_status(info);
+	if (ack) {
+		RT_TRACE(rtlpriv, COMP_TX_REPORT, DBG_LOUD,
+			 "tx report: ack\n");
+		info->flags |= IEEE80211_TX_STAT_ACK;
+	} else {
+		RT_TRACE(rtlpriv, COMP_TX_REPORT, DBG_LOUD,
+			 "tx report: not ack\n");
+		info->flags &= ~IEEE80211_TX_STAT_ACK;
+	}
+	ieee80211_tx_status_irqsafe(hw, skb);
+}
+
 bool rtl_is_tx_report_skb(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
 	u16 ether_type;
 	const u8 *ether_type_ptr;
+	__le16 fc = rtl_get_fc(skb);
 
 	ether_type_ptr = rtl_skb_ether_type_ptr(hw, skb, true);
 	ether_type = be16_to_cpup((__be16 *)ether_type_ptr);
 
-	/* EAPOL */
-	if (ether_type == ETH_P_PAE)
+	if (ether_type == ETH_P_PAE || ieee80211_is_nullfunc(fc))
 		return true;
 
 	return false;
 }
 
-static u16 rtl_get_tx_report_sn(struct ieee80211_hw *hw)
+static u16 rtl_get_tx_report_sn(struct ieee80211_hw *hw,
+				struct rtlwifi_tx_info *tx_info)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_tx_report *tx_report = &rtlpriv->tx_report;
@@ -1604,29 +1638,33 @@ static u16 rtl_get_tx_report_sn(struct ieee80211_hw *hw)
 
 	tx_report->last_sent_sn = sn;
 	tx_report->last_sent_time = jiffies;
-
+	tx_info->sn = sn;
+	tx_info->send_time = tx_report->last_sent_time;
 	RT_TRACE(rtlpriv, COMP_TX_REPORT, DBG_DMESG,
 		 "Send TX-Report sn=0x%X\n", sn);
 
 	return sn;
 }
 
-void rtl_get_tx_report(struct rtl_tcb_desc *ptcb_desc, u8 *pdesc,
-		       struct ieee80211_hw *hw)
+void rtl_set_tx_report(struct rtl_tcb_desc *ptcb_desc, u8 *pdesc,
+		       struct ieee80211_hw *hw, struct rtlwifi_tx_info *tx_info)
 {
 	if (ptcb_desc->use_spe_rpt) {
-		u16 sn = rtl_get_tx_report_sn(hw);
+		u16 sn = rtl_get_tx_report_sn(hw, tx_info);
 
 		SET_TX_DESC_SPE_RPT(pdesc, 1);
 		SET_TX_DESC_SW_DEFINE(pdesc, sn);
 	}
 }
-EXPORT_SYMBOL_GPL(rtl_get_tx_report);
+EXPORT_SYMBOL_GPL(rtl_set_tx_report);
 
 void rtl_tx_report_handler(struct ieee80211_hw *hw, u8 *tmp_buf, u8 c2h_cmd_len)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_tx_report *tx_report = &rtlpriv->tx_report;
+	struct rtlwifi_tx_info *tx_info;
+	struct sk_buff_head *queue = &tx_report->queue;
+	struct sk_buff *skb;
 	u16 sn;
 	u8 st, retry;
 
@@ -1642,6 +1680,14 @@ void rtl_tx_report_handler(struct ieee80211_hw *hw, u8 *tmp_buf, u8 c2h_cmd_len)
 
 	tx_report->last_recv_sn = sn;
 
+	skb_queue_walk(queue, skb) {
+		tx_info = rtl_tx_skb_cb_info(skb);
+		if (tx_info->sn == sn) {
+			skb_unlink(skb, queue);
+			rtl_tx_status(hw, skb, st == 0);
+			break;
+		}
+	}
 	RT_TRACE(rtlpriv, COMP_TX_REPORT, DBG_DMESG,
 		 "Recv TX-Report st=0x%02X sn=0x%X retry=0x%X\n",
 		 st, sn, retry);
@@ -1909,6 +1955,25 @@ static void rtl_free_entries_from_scan_list(struct ieee80211_hw *hw)
 	}
 }
 
+static void rtl_free_entries_from_ack_queue(struct ieee80211_hw *hw,
+					    bool chk_timeout)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	struct rtl_tx_report *tx_report = &rtlpriv->tx_report;
+	struct sk_buff_head *queue = &tx_report->queue;
+	struct sk_buff *skb, *tmp;
+	struct rtlwifi_tx_info *tx_info;
+
+	skb_queue_walk_safe(queue, skb, tmp) {
+		tx_info = rtl_tx_skb_cb_info(skb);
+		if (chk_timeout &&
+		    time_after(tx_info->send_time + HZ, jiffies))
+			continue;
+		skb_unlink(skb, queue);
+		rtl_tx_status(hw, skb, false);
+	}
+}
+
 void rtl_scan_list_expire(struct ieee80211_hw *hw)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
@@ -2173,6 +2238,9 @@ void rtl_watchdog_wq_callback(void *data)
 
 	/* <6> scan list */
 	rtl_scan_list_expire(hw);
+
+	/* <7> check ack queue */
+	rtl_free_entries_from_ack_queue(hw, true);
 }
 
 void rtl_watch_dog_timer_callback(struct timer_list *t)

drivers/net/wireless/realtek/rtlwifi/base.h

@@ -130,9 +130,10 @@ bool rtl_tx_mgmt_proc(struct ieee80211_hw *hw, struct sk_buff *skb);
 u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx,
 		       bool is_enc);
 
+void rtl_tx_ackqueue(struct ieee80211_hw *hw, struct sk_buff *skb);
 bool rtl_is_tx_report_skb(struct ieee80211_hw *hw, struct sk_buff *skb);
-void rtl_get_tx_report(struct rtl_tcb_desc *ptcb_desc, u8 *pdesc,
-		       struct ieee80211_hw *hw);
+void rtl_set_tx_report(struct rtl_tcb_desc *ptcb_desc, u8 *pdesc,
+		       struct ieee80211_hw *hw, struct rtlwifi_tx_info *info);
 void rtl_tx_report_handler(struct ieee80211_hw *hw, u8 *tmp_buf,
 			   u8 c2h_cmd_len);
 bool rtl_check_tx_report_acked(struct ieee80211_hw *hw);

drivers/net/wireless/realtek/rtlwifi/pci.c

@@ -619,12 +619,15 @@ static void _rtl_pci_tx_isr(struct ieee80211_hw *hw, int prio)
 			rtlpriv->link_info.tidtx_inperiod[tid]++;
 
 		info = IEEE80211_SKB_CB(skb);
-		ieee80211_tx_info_clear_status(info);
 
+		if (likely(!ieee80211_is_nullfunc(fc))) {
+			ieee80211_tx_info_clear_status(info);
 			info->flags |= IEEE80211_TX_STAT_ACK;
 			/*info->status.rates[0].count = 1; */
-
 			ieee80211_tx_status_irqsafe(hw, skb);
+		} else {
+			rtl_tx_ackqueue(hw, skb);
+		}
 
 		if ((ring->entries - skb_queue_len(&ring->queue)) <= 4) {
 			RT_TRACE(rtlpriv, COMP_ERR, DBG_DMESG,

drivers/net/wireless/realtek/rtlwifi/rtl8192ee/trx.c

@@ -662,6 +662,7 @@ void rtl92ee_tx_fill_desc(struct ieee80211_hw *hw,
 	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
 	struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw));
 	struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
+	struct rtlwifi_tx_info *tx_info = rtl_tx_skb_cb_info(skb);
 	u8 *pdesc = (u8 *)pdesc_tx;
 	u16 seq_number;
 	__le16 fc = hdr->frame_control;
@@ -723,8 +724,6 @@ void rtl92ee_tx_fill_desc(struct ieee80211_hw *hw,
 			SET_TX_DESC_OFFSET(pdesc, USB_HWDESC_HEADER_LEN);
 		}
 
-		/* tx report */
-		rtl_get_tx_report(ptcb_desc, pdesc, hw);
 
 		SET_TX_DESC_TX_RATE(pdesc, ptcb_desc->hw_rate);
 
@@ -827,6 +826,8 @@ void rtl92ee_tx_fill_desc(struct ieee80211_hw *hw,
 				SET_TX_DESC_HTC(pdesc, 1);
 			}
 		}
+		/* tx report */
+		rtl_set_tx_report(ptcb_desc, pdesc, hw, tx_info);
 	}
 
 	SET_TX_DESC_FIRST_SEG(pdesc, (firstseg ? 1 : 0));

drivers/net/wireless/realtek/rtlwifi/rtl8723be/trx.c

@@ -431,6 +431,7 @@ void rtl8723be_tx_fill_desc(struct ieee80211_hw *hw,
 	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
 	struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw));
 	struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
+	struct rtlwifi_tx_info *tx_info = rtl_tx_skb_cb_info(skb);
 	u8 *pdesc = (u8 *)pdesc_tx;
 	u16 seq_number;
 	__le16 fc = hdr->frame_control;
@@ -488,8 +489,6 @@ void rtl8723be_tx_fill_desc(struct ieee80211_hw *hw,
 			SET_TX_DESC_OFFSET(pdesc, USB_HWDESC_HEADER_LEN);
 		}
 
-		/* tx report */
-		rtl_get_tx_report(ptcb_desc, pdesc, hw);
 
 		/* ptcb_desc->use_driver_rate = true; */
 		SET_TX_DESC_TX_RATE(pdesc, ptcb_desc->hw_rate);
@@ -578,6 +577,8 @@ void rtl8723be_tx_fill_desc(struct ieee80211_hw *hw,
 				SET_TX_DESC_HTC(pdesc, 1);
 			}
 		}
+		/* tx report */
+		rtl_set_tx_report(ptcb_desc, pdesc, hw, tx_info);
 	}
 
 	SET_TX_DESC_FIRST_SEG(pdesc, (firstseg ? 1 : 0));

drivers/net/wireless/realtek/rtlwifi/rtl8821ae/trx.c

@@ -691,6 +691,7 @@ void rtl8821ae_tx_fill_desc(struct ieee80211_hw *hw,
 	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
 	struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw));
 	struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
+	struct rtlwifi_tx_info *tx_info = rtl_tx_skb_cb_info(skb);
 	u8 *pdesc = (u8 *)pdesc_tx;
 	u16 seq_number;
 	__le16 fc = hdr->frame_control;
@@ -740,8 +741,6 @@ void rtl8821ae_tx_fill_desc(struct ieee80211_hw *hw,
 			SET_TX_DESC_OFFSET(pdesc, USB_HWDESC_HEADER_LEN);
 		}
 
-		/* tx report */
-		rtl_get_tx_report(ptcb_desc, pdesc, hw);
 
 		/* ptcb_desc->use_driver_rate = true; */
 		SET_TX_DESC_TX_RATE(pdesc, ptcb_desc->hw_rate);
@@ -818,6 +817,8 @@ void rtl8821ae_tx_fill_desc(struct ieee80211_hw *hw,
 				SET_TX_DESC_HTC(pdesc, 1);
 			}
 		}
+		/* tx report */
+		rtl_set_tx_report(ptcb_desc, pdesc, hw, tx_info);
 	}
 
 	SET_TX_DESC_FIRST_SEG(pdesc, (firstseg ? 1 : 0));

drivers/net/wireless/realtek/rtlwifi/wifi.h

@@ -1010,6 +1010,21 @@ enum dm_info_query {
 	DM_INFO_SIZE,
 };
 
+struct rtlwifi_tx_info {
+	int sn;
+	unsigned long send_time;
+};
+
+static inline struct rtlwifi_tx_info *rtl_tx_skb_cb_info(struct sk_buff *skb)
+{
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+	BUILD_BUG_ON(sizeof(struct rtlwifi_tx_info) >
+		     sizeof(info->status.status_driver_data));
+
+	return (struct rtlwifi_tx_info *)(info->status.status_driver_data);
+}
+
 struct octet_string {
 	u8 *octet;
 	u16 length;
@@ -1967,6 +1982,7 @@ struct rtl_tx_report {
 	u16 last_sent_sn;
 	unsigned long last_sent_time;
 	u16 last_recv_sn;
+	struct sk_buff_head queue;
 };
 
 struct rtl_ps_ctl {