Linux wireless drivers development
 help / color / mirror / Atom feed
* [PATCH ath-current v2] wifi: ath12k: fix DMA direction for re-injected Rx buffers
@ 2026-10-23  9:25 Lorenzo Bianconi
  2026-10-23 11:04 ` Baochen Qiang
  0 siblings, 1 reply; 3+ messages in thread
From: Lorenzo Bianconi @ 2026-10-23  9:25 UTC (permalink / raw)
  To: Jeff Johnson, Kalle Valo, Baochen Qiang
  Cc: Jeff Johnson, linux-wireless, ath12k, Lorenzo Bianconi

Defragmented MPDUs that are re-injected into the REO are mapped with
DMA_TO_DEVICE, but all the Rx reap and teardown paths unmap them with
DMA_FROM_DEVICE. The DMA API requires the unmap direction to match the
map direction, so this violates the contract.

The mapping actually spans both directions, since the host has written
the buffer before the REO reads it and the buffer is read back by the
host afterwards, so DMA_BIDIRECTIONAL is the correct choice.

Add a common ath12k_dp_unmap_rx_buf() helper that selects
DMA_BIDIRECTIONAL for re-injected buffers, identified by the existing
ath12k_skb_rxcb::is_frag flag, and DMA_FROM_DEVICE otherwise, then use it
in all the Rx reap and cleanup paths. Map and unmap the re-injected buffer
with DMA_BIDIRECTIONAL consistently.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3

Fixes: 33322e3ef074 ("wifi: ath12k: change DMA direction while mapping reinjected packets")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>
---
Changes in v2:
- Rely on ath12k_skb_rxcb is_frag field and drop reinjected one.
- Link to v1: https://lore.kernel.org/r/20261017-ath12k-fix-dma-mapping-for-reinject-packets-v1-1-b94860e18ba4@oss.qualcomm.com
---
 drivers/net/wireless/ath/ath12k/dp.c           |  6 ++---
 drivers/net/wireless/ath/ath12k/dp_mon.c       |  5 ++--
 drivers/net/wireless/ath/ath12k/dp_rx.c        |  3 +--
 drivers/net/wireless/ath/ath12k/dp_rx.h        | 11 +++++++++
 drivers/net/wireless/ath/ath12k/wifi7/dp_mon.c | 17 ++++---------
 drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c  | 33 +++++++-------------------
 6 files changed, 29 insertions(+), 46 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/dp.c b/drivers/net/wireless/ath/ath12k/dp.c
index f9b37d75956d..bca719b30281 100644
--- a/drivers/net/wireless/ath/ath12k/dp.c
+++ b/drivers/net/wireless/ath/ath12k/dp.c
@@ -5,6 +5,7 @@
  */
 
 #include "core.h"
+#include "dp_rx.h"
 #include "dp_tx.h"
 #include "hif.h"
 #include "hal.h"
@@ -998,10 +999,7 @@ static void ath12k_dp_cc_cleanup(struct ath12k_base *ab)
 				if (!skb)
 					continue;
 
-				dma_unmap_single(ab->dev,
-						 ATH12K_SKB_RXCB(skb)->paddr,
-						 skb->len + skb_tailroom(skb),
-						 DMA_FROM_DEVICE);
+				ath12k_dp_unmap_rx_buf(dp, skb);
 				dev_kfree_skb_any(skb);
 			}
 
diff --git a/drivers/net/wireless/ath/ath12k/dp_mon.c b/drivers/net/wireless/ath/ath12k/dp_mon.c
index 7d5be77b081f..8fca50b0f236 100644
--- a/drivers/net/wireless/ath/ath12k/dp_mon.c
+++ b/drivers/net/wireless/ath/ath12k/dp_mon.c
@@ -5,6 +5,7 @@
  */
 
 #include "dp_mon.h"
+#include "dp_rx.h"
 #include "debug.h"
 #include "dp_tx.h"
 #include "peer.h"
@@ -561,9 +562,7 @@ ath12k_dp_mon_parse_status_buf(struct ath12k_pdev_dp *dp_pdev,
 		return 0;
 	}
 
-	dma_unmap_single(ab->dev, ATH12K_SKB_RXCB(msdu)->paddr,
-			 msdu->len + skb_tailroom(msdu),
-			 DMA_FROM_DEVICE);
+	ath12k_dp_unmap_rx_buf(dp, msdu);
 
 	offset = packet_info->dma_length + ATH12K_MON_RX_DOT11_OFFSET;
 	if (ath12k_dp_pkt_set_pktlen(msdu, offset)) {
diff --git a/drivers/net/wireless/ath/ath12k/dp_rx.c b/drivers/net/wireless/ath/ath12k/dp_rx.c
index 8fa0e90b4531..ac489d9bfb55 100644
--- a/drivers/net/wireless/ath/ath12k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath12k/dp_rx.c
@@ -185,8 +185,7 @@ static int ath12k_dp_rxdma_mon_buf_ring_free(struct ath12k_base *ab,
 		/* TODO: Understand where internal driver does this dma_unmap
 		 * of rxdma_buffer.
 		 */
-		dma_unmap_single(ab->dev, ATH12K_SKB_RXCB(skb)->paddr,
-				 skb->len + skb_tailroom(skb), DMA_FROM_DEVICE);
+		ath12k_dp_unmap_rx_buf(ath12k_ab_to_dp(ab), skb);
 		dev_kfree_skb_any(skb);
 	}
 
diff --git a/drivers/net/wireless/ath/ath12k/dp_rx.h b/drivers/net/wireless/ath/ath12k/dp_rx.h
index 0660db070e92..f6eda3a0f45b 100644
--- a/drivers/net/wireless/ath/ath12k/dp_rx.h
+++ b/drivers/net/wireless/ath/ath12k/dp_rx.h
@@ -187,6 +187,17 @@ void ath12k_dp_extract_rx_desc_data(struct ath12k_hal *hal,
 	hal->ops->extract_rx_desc_data(rx_info, rx_desc, ldesc);
 }
 
+static inline void ath12k_dp_unmap_rx_buf(struct ath12k_dp *dp,
+					  struct sk_buff *skb)
+{
+	struct ath12k_skb_rxcb *rxcb = ATH12K_SKB_RXCB(skb);
+	enum dma_data_direction dir;
+
+	dir = rxcb->is_frag ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
+	dma_unmap_single(dp->dev, rxcb->paddr, skb->len + skb_tailroom(skb),
+			 dir);
+}
+
 void ath12k_dp_rx_h_undecap(struct ath12k_pdev_dp *dp_pdev, struct sk_buff *msdu,
 			    enum hal_encrypt_type enctype,
 			    bool decrypted,
diff --git a/drivers/net/wireless/ath/ath12k/wifi7/dp_mon.c b/drivers/net/wireless/ath/ath12k/wifi7/dp_mon.c
index 016b0c38e51e..1e0e089bc1b4 100644
--- a/drivers/net/wireless/ath/ath12k/wifi7/dp_mon.c
+++ b/drivers/net/wireless/ath/ath12k/wifi7/dp_mon.c
@@ -2721,10 +2721,7 @@ ath12k_wifi7_dp_rx_mon_mpdu_pop(struct ath12k *ar, int mac_id,
 				continue;
 			}
 			if (!rxcb->unmapped) {
-				dma_unmap_single(ar->ab->dev, rxcb->paddr,
-						 msdu->len +
-						 skb_tailroom(msdu),
-						 DMA_FROM_DEVICE);
+				ath12k_dp_unmap_rx_buf(dp, msdu);
 				rxcb->unmapped = 1;
 			}
 			if (drop_mpdu) {
@@ -3137,9 +3134,7 @@ ath12k_wifi7_dp_rx_reap_mon_status_ring(struct ath12k_base *ab, int mac_id,
 				idr_remove(&rx_ring->bufs_idr, buf_id);
 				spin_unlock_bh(&rx_ring->idr_lock);
 
-				dma_unmap_single(ab->dev, rxcb->paddr,
-						 skb->len + skb_tailroom(skb),
-						 DMA_FROM_DEVICE);
+				ath12k_dp_unmap_rx_buf(dp, skb);
 
 				dev_kfree_skb_any(skb);
 				pmon->buf_state = DP_MON_STATUS_REPLINISH;
@@ -3150,9 +3145,7 @@ ath12k_wifi7_dp_rx_reap_mon_status_ring(struct ath12k_base *ab, int mac_id,
 			idr_remove(&rx_ring->bufs_idr, buf_id);
 			spin_unlock_bh(&rx_ring->idr_lock);
 
-			dma_unmap_single(ab->dev, rxcb->paddr,
-					 skb->len + skb_tailroom(skb),
-					 DMA_FROM_DEVICE);
+			ath12k_dp_unmap_rx_buf(dp, skb);
 
 			if (ath12k_dp_pkt_set_pktlen(skb, RX_MON_STATUS_BUF_SIZE)) {
 				dev_kfree_skb_any(skb);
@@ -3289,9 +3282,7 @@ ath12k_wifi7_dp_mon_srng_process(struct ath12k_pdev_dp *pdev_dp, int *budget,
 		}
 
 		rxcb = ATH12K_SKB_RXCB(skb);
-		dma_unmap_single(ab->dev, rxcb->paddr,
-				 skb->len + skb_tailroom(skb),
-				 DMA_FROM_DEVICE);
+		ath12k_dp_unmap_rx_buf(dp, skb);
 
 		end_reason = u32_get_bits(info0, HAL_MON_DEST_INFO0_END_REASON);
 
diff --git a/drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c b/drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c
index 95d87dd67872..7fcf31aadf49 100644
--- a/drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c
+++ b/drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c
@@ -729,11 +729,7 @@ int ath12k_wifi7_dp_rx_process(struct ath12k_dp *dp, int ring_id,
 
 		list_add_tail(&desc_info->list, &rx_desc_used_list[device_id]);
 
-		rxcb = ATH12K_SKB_RXCB(msdu);
-		dma_unmap_single(partner_dp->dev, rxcb->paddr,
-				 msdu->len + skb_tailroom(msdu),
-				 DMA_FROM_DEVICE);
-
+		ath12k_dp_unmap_rx_buf(partner_dp, msdu);
 		num_buffs_reaped[device_id]++;
 		dp->device_stats.reo_rx[ring_id][dp->device_id]++;
 
@@ -749,6 +745,7 @@ int ath12k_wifi7_dp_rx_process(struct ath12k_dp *dp, int ring_id,
 		msdu_info = &desc->rx_msdu_info;
 		mpdu_info = &desc->rx_mpdu_info;
 
+		rxcb = ATH12K_SKB_RXCB(msdu);
 		rxcb->is_first_msdu = !!(le32_to_cpu(msdu_info->info0) &
 					 RX_MSDU_DESC_INFO0_FIRST_MSDU_IN_MPDU);
 		rxcb->is_last_msdu = !!(le32_to_cpu(msdu_info->info0) &
@@ -894,7 +891,7 @@ static int ath12k_wifi7_dp_rx_h_defrag_reo_reinject(struct ath12k_dp *dp,
 
 	buf_paddr = dma_map_single(dp->dev, defrag_skb->data,
 				   defrag_skb->len + skb_tailroom(defrag_skb),
-				   DMA_TO_DEVICE);
+				   DMA_BIDIRECTIONAL);
 	if (dma_mapping_error(dp->dev, buf_paddr))
 		return -ENOMEM;
 
@@ -983,8 +980,8 @@ static int ath12k_wifi7_dp_rx_h_defrag_reo_reinject(struct ath12k_dp *dp,
 	list_add_tail(&desc_info->list, &dp->rx_desc_free_list);
 	spin_unlock_bh(&dp->rx_desc_lock);
 err_unmap_dma:
-	dma_unmap_single(dp->dev, buf_paddr, defrag_skb->len + skb_tailroom(defrag_skb),
-			 DMA_TO_DEVICE);
+	ath12k_dp_unmap_rx_buf(dp, defrag_skb);
+
 	return ret;
 }
 
@@ -1286,7 +1283,6 @@ ath12k_wifi7_dp_process_rx_err_buf(struct ath12k_pdev_dp *dp_pdev,
 	struct ath12k_dp *dp = dp_pdev->dp;
 	struct ath12k_hal *hal = dp->hal;
 	struct sk_buff *msdu;
-	struct ath12k_skb_rxcb *rxcb;
 	struct hal_rx_desc_data rx_info;
 	struct hal_rx_desc *rx_desc;
 	u16 msdu_len;
@@ -1316,11 +1312,7 @@ ath12k_wifi7_dp_process_rx_err_buf(struct ath12k_pdev_dp *dp_pdev,
 	desc_info->skb = NULL;
 
 	list_add_tail(&desc_info->list, used_list);
-
-	rxcb = ATH12K_SKB_RXCB(msdu);
-	dma_unmap_single(dp->dev, rxcb->paddr,
-			 msdu->len + skb_tailroom(msdu),
-			 DMA_FROM_DEVICE);
+	ath12k_dp_unmap_rx_buf(dp, msdu);
 
 	if (drop) {
 		dev_kfree_skb_any(msdu);
@@ -1367,7 +1359,6 @@ static int ath12k_dp_h_msdu_buffer_type(struct ath12k_dp *dp,
 					struct hal_reo_dest_ring *desc)
 {
 	struct ath12k_rx_desc_info *desc_info;
-	struct ath12k_skb_rxcb *rxcb;
 	struct sk_buff *msdu;
 	u64 desc_va;
 
@@ -1398,9 +1389,7 @@ static int ath12k_dp_h_msdu_buffer_type(struct ath12k_dp *dp,
 	msdu = desc_info->skb;
 	desc_info->skb = NULL;
 	list_add_tail(&desc_info->list, list);
-	rxcb = ATH12K_SKB_RXCB(msdu);
-	dma_unmap_single(dp->dev, rxcb->paddr, msdu->len + skb_tailroom(msdu),
-			 DMA_FROM_DEVICE);
+	ath12k_dp_unmap_rx_buf(dp, msdu);
 	dev_kfree_skb_any(msdu);
 
 	return 0;
@@ -1971,12 +1960,7 @@ int ath12k_wifi7_dp_rx_process_wbm_err(struct ath12k_dp *dp,
 		}
 
 		list_add_tail(&desc_info->list, &rx_desc_used_list[device_id]);
-
-		rxcb = ATH12K_SKB_RXCB(msdu);
-		dma_unmap_single(partner_dp->dev, rxcb->paddr,
-				 msdu->len + skb_tailroom(msdu),
-				 DMA_FROM_DEVICE);
-
+		ath12k_dp_unmap_rx_buf(partner_dp, msdu);
 		num_buffs_reaped[device_id]++;
 		total_num_buffs_reaped++;
 
@@ -1990,6 +1974,7 @@ int ath12k_wifi7_dp_rx_process_wbm_err(struct ath12k_dp *dp,
 		}
 
 		msdu_data = (struct hal_rx_desc *)msdu->data;
+		rxcb = ATH12K_SKB_RXCB(msdu);
 		rxcb->err_rel_src = err_info.err_rel_src;
 		rxcb->err_code = err_info.err_code;
 		rxcb->is_first_msdu = err_info.first_msdu;

---
base-commit: dc6e3cef4322996e131c618295be2b3c2fc5cd1f
change-id: 20261014-ath12k-fix-dma-mapping-for-reinject-packets-2eab34ca5acc

Best regards,
-- 
Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH ath-current v2] wifi: ath12k: fix DMA direction for re-injected Rx buffers
  2026-10-23  9:25 [PATCH ath-current v2] wifi: ath12k: fix DMA direction for re-injected Rx buffers Lorenzo Bianconi
@ 2026-10-23 11:04 ` Baochen Qiang
  2026-10-23 12:40   ` Lorenzo Bianconi
  0 siblings, 1 reply; 3+ messages in thread
From: Baochen Qiang @ 2026-10-23 11:04 UTC (permalink / raw)
  To: Lorenzo Bianconi, Jeff Johnson, Kalle Valo, Baochen Qiang
  Cc: Jeff Johnson, linux-wireless, ath12k



On 10/23/2026 5:25 PM, Lorenzo Bianconi wrote:

> @@ -983,8 +980,8 @@ static int ath12k_wifi7_dp_rx_h_defrag_reo_reinject(struct ath12k_dp *dp,
>  	list_add_tail(&desc_info->list, &dp->rx_desc_free_list);
>  	spin_unlock_bh(&dp->rx_desc_lock);
>  err_unmap_dma:
> -	dma_unmap_single(dp->dev, buf_paddr, defrag_skb->len + skb_tailroom(defrag_skb),
> -			 DMA_TO_DEVICE);
> +	ath12k_dp_unmap_rx_buf(dp, defrag_skb);

buf_paddr has not been updated to skb_cb->paddr when we reach here. v1 has

rxcb->paddr = buf_paddr;

before jumping, so v1 is good.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH ath-current v2] wifi: ath12k: fix DMA direction for re-injected Rx buffers
  2026-10-23 11:04 ` Baochen Qiang
@ 2026-10-23 12:40   ` Lorenzo Bianconi
  0 siblings, 0 replies; 3+ messages in thread
From: Lorenzo Bianconi @ 2026-10-23 12:40 UTC (permalink / raw)
  To: Baochen Qiang
  Cc: Jeff Johnson, Kalle Valo, Baochen Qiang, Jeff Johnson,
	linux-wireless, ath12k

[-- Attachment #1: Type: text/plain, Size: 661 bytes --]

> 
> 
> On 10/23/2026 5:25 PM, Lorenzo Bianconi wrote:
> 
> > @@ -983,8 +980,8 @@ static int ath12k_wifi7_dp_rx_h_defrag_reo_reinject(struct ath12k_dp *dp,
> >  	list_add_tail(&desc_info->list, &dp->rx_desc_free_list);
> >  	spin_unlock_bh(&dp->rx_desc_lock);
> >  err_unmap_dma:
> > -	dma_unmap_single(dp->dev, buf_paddr, defrag_skb->len + skb_tailroom(defrag_skb),
> > -			 DMA_TO_DEVICE);
> > +	ath12k_dp_unmap_rx_buf(dp, defrag_skb);
> 
> buf_paddr has not been updated to skb_cb->paddr when we reach here. v1 has
> 
> rxcb->paddr = buf_paddr;
> 
> before jumping, so v1 is good.

Right, my bad. I will fix it in v3.

Regards,
Lorenzo

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2026-10-23 12:40 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-10-23  9:25 [PATCH ath-current v2] wifi: ath12k: fix DMA direction for re-injected Rx buffers Lorenzo Bianconi
2026-10-23 11:04 ` Baochen Qiang
2026-10-23 12:40   ` Lorenzo Bianconi

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox