ath10k: dma unmap mgmt tx buffer if wmi cmd send fails

WCN3990 sends mgmt frames by reference via WMI.
The host dma maps the mgmt frame and sends the physical
address to the firmware in the wmi command. Since the
dma mapping is done in the gen_mgmt_tx and if the wmi
command send fails, the corresponding mgmt frame is
not being dma unmapped.

Fix the missing dma unmapping of mgmt tx frame when
wmi command sending fails for mgmt tx by reference
via WMI. The already exisiting mgmt tx using copy by
value does not need such dma unmapping.
Add a separate wmi-tlv op for mgmt tx via ref, which
takes care of unmapping the dma address, in case of
wmi command sending failure.
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath10k/mac.c

 /*
  * Copyright (c) 2005-2011 Atheros Communications Inc.
  * Copyright (c) 2011-2017 Qualcomm Atheros, Inc.
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -3808,6 +3809,7 @@ void ath10k_mgmt_over_wmi_tx_work(struct work_struct *work)
 {
 	struct ath10k *ar = container_of(work, struct ath10k, wmi_mgmt_tx_work);
 	struct sk_buff *skb;
+	dma_addr_t paddr;
 	int ret;
 
 	for (;;) {
@@ -3815,11 +3817,27 @@ void ath10k_mgmt_over_wmi_tx_work(struct work_struct *work)
 		if (!skb)
 			break;
 
-		ret = ath10k_wmi_mgmt_tx(ar, skb);
-		if (ret) {
-			ath10k_warn(ar, "failed to transmit management frame via WMI: %d\n",
-				    ret);
-			ieee80211_free_txskb(ar->hw, skb);
+		if (test_bit(ATH10K_FW_FEATURE_MGMT_TX_BY_REF,
+			     ar->running_fw->fw_file.fw_features)) {
+			paddr = dma_map_single(ar->dev, skb->data,
+					       skb->len, DMA_TO_DEVICE);
+			if (!paddr)
+				continue;
+			ret = ath10k_wmi_mgmt_tx_send(ar, skb, paddr);
+			if (ret) {
+				ath10k_warn(ar, "failed to transmit management frame by ref via WMI: %d\n",
+					    ret);
+				dma_unmap_single(ar->dev, paddr, skb->len,
+						 DMA_FROM_DEVICE);
+				ieee80211_free_txskb(ar->hw, skb);
+			}
+		} else {
+			ret = ath10k_wmi_mgmt_tx(ar, skb);
+			if (ret) {
+				ath10k_warn(ar, "failed to transmit management frame via WMI: %d\n",
+					    ret);
+				ieee80211_free_txskb(ar->hw, skb);
+			}
 		}
 	}
 }

drivers/net/wireless/ath/ath10k/wmi-ops.h

 /*
  * Copyright (c) 2005-2011 Atheros Communications Inc.
  * Copyright (c) 2011-2017 Qualcomm Atheros, Inc.
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -125,6 +126,9 @@ struct wmi_ops {
 					     enum wmi_force_fw_hang_type type,
 					     u32 delay_ms);
 	struct sk_buff *(*gen_mgmt_tx)(struct ath10k *ar, struct sk_buff *skb);
+	struct sk_buff *(*gen_mgmt_tx_send)(struct ath10k *ar,
+					    struct sk_buff *skb,
+					    dma_addr_t paddr);
 	struct sk_buff *(*gen_dbglog_cfg)(struct ath10k *ar, u64 module_enable,
 					  u32 log_level);
 	struct sk_buff *(*gen_pktlog_enable)(struct ath10k *ar, u32 filter);
@@ -371,13 +375,34 @@ ath10k_wmi_get_txbf_conf_scheme(struct ath10k *ar)
 	return ar->wmi.ops->get_txbf_conf_scheme(ar);
 }
 
+static inline int
+ath10k_wmi_mgmt_tx_send(struct ath10k *ar, struct sk_buff *msdu,
+			dma_addr_t paddr)
+{
+	struct sk_buff *skb;
+	int ret;
+
+	if (!ar->wmi.ops->gen_mgmt_tx_send)
+		return -EOPNOTSUPP;
+
+	skb = ar->wmi.ops->gen_mgmt_tx_send(ar, msdu, paddr);
+	if (IS_ERR(skb))
+		return PTR_ERR(skb);
+
+	ret = ath10k_wmi_cmd_send(ar, skb,
+				  ar->wmi.cmd->mgmt_tx_send_cmdid);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static inline int
 ath10k_wmi_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
 {
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(msdu);
 	struct sk_buff *skb;
 	int ret;
-	u32 mgmt_tx_cmdid;
 
 	if (!ar->wmi.ops->gen_mgmt_tx)
 		return -EOPNOTSUPP;
@@ -386,13 +411,8 @@ ath10k_wmi_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
 	if (IS_ERR(skb))
 		return PTR_ERR(skb);
 
-	if (test_bit(ATH10K_FW_FEATURE_MGMT_TX_BY_REF,
-		     ar->running_fw->fw_file.fw_features))
-		mgmt_tx_cmdid = ar->wmi.cmd->mgmt_tx_send_cmdid;
-	else
-		mgmt_tx_cmdid = ar->wmi.cmd->mgmt_tx_cmdid;
-
-	ret = ath10k_wmi_cmd_send(ar, skb, mgmt_tx_cmdid);
+	ret = ath10k_wmi_cmd_send(ar, skb,
+				  ar->wmi.cmd->mgmt_tx_cmdid);
 	if (ret)
 		return ret;
 

drivers/net/wireless/ath/ath10k/wmi-tlv.c

 /*
  * Copyright (c) 2005-2011 Atheros Communications Inc.
  * Copyright (c) 2011-2017 Qualcomm Atheros, Inc.
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -2484,19 +2485,19 @@ ath10k_wmi_tlv_op_gen_request_stats(struct ath10k *ar, u32 stats_mask)
 }
 
 static struct sk_buff *
-ath10k_wmi_tlv_op_gen_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
+ath10k_wmi_tlv_op_gen_mgmt_tx_send(struct ath10k *ar, struct sk_buff *msdu,
+				   dma_addr_t paddr)
 {
 	struct ath10k_skb_cb *cb = ATH10K_SKB_CB(msdu);
 	struct wmi_tlv_mgmt_tx_cmd *cmd;
-	struct wmi_tlv *tlv;
 	struct ieee80211_hdr *hdr;
+	struct ath10k_vif *arvif;
+	u32 buf_len = msdu->len;
+	struct wmi_tlv *tlv;
 	struct sk_buff *skb;
+	u32 vdev_id;
 	void *ptr;
 	int len;
-	u32 buf_len = msdu->len;
-	struct ath10k_vif *arvif;
-	dma_addr_t mgmt_frame_dma;
-	u32 vdev_id;
 
 	if (!cb->vif)
 		return ERR_PTR(-EINVAL);
@@ -2537,12 +2538,7 @@ ath10k_wmi_tlv_op_gen_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
 	cmd->chanfreq = 0;
 	cmd->buf_len = __cpu_to_le32(buf_len);
 	cmd->frame_len = __cpu_to_le32(msdu->len);
-	mgmt_frame_dma = dma_map_single(arvif->ar->dev, msdu->data,
-					msdu->len, DMA_TO_DEVICE);
-	if (!mgmt_frame_dma)
-		return ERR_PTR(-ENOMEM);
-
-	cmd->paddr = __cpu_to_le64(mgmt_frame_dma);
+	cmd->paddr = __cpu_to_le64(paddr);
 
 	ptr += sizeof(*tlv);
 	ptr += sizeof(*cmd);
@@ -3701,7 +3697,7 @@ static const struct wmi_ops wmi_tlv_ops = {
 	.gen_request_stats = ath10k_wmi_tlv_op_gen_request_stats,
 	.gen_force_fw_hang = ath10k_wmi_tlv_op_gen_force_fw_hang,
 	/* .gen_mgmt_tx = not implemented; HTT is used */
-	.gen_mgmt_tx =  ath10k_wmi_tlv_op_gen_mgmt_tx,
+	.gen_mgmt_tx_send = ath10k_wmi_tlv_op_gen_mgmt_tx_send,
 	.gen_dbglog_cfg = ath10k_wmi_tlv_op_gen_dbglog_cfg,
 	.gen_pktlog_enable = ath10k_wmi_tlv_op_gen_pktlog_enable,
 	.gen_pktlog_disable = ath10k_wmi_tlv_op_gen_pktlog_disable,