[PATCH 7/9] wifi: ath12k: fix ath12k_qmi_alloc_chunk() to handle too large allocations

[Kalle Valo]

From: Aditya Kumar Singh <quic_adisi at quicinc.com>

If the requested memory chunk is too large, an error message is logged, but the
request continues to be processed. However, no actual memory is allocated to
the firmware from this request. Instead, the firmware sends another request
with smaller chunks, where memory will be allocated accordingly. Therefore, it
is pointless to proceed with parsing the request if at least one of the
requests cannot be fulfilled.

Hence, return -EAGAIN immediately and proceed to process the new request.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: Aditya Kumar Singh <quic_adisi at quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo at quicinc.com>
---
 drivers/net/wireless/ath/ath12k/qmi.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath12k/qmi.c b/drivers/net/wireless/ath/ath12k/qmi.c
index e7846aaca10a..964d350be748 100644
--- a/drivers/net/wireless/ath/ath12k/qmi.c
+++ b/drivers/net/wireless/ath/ath12k/qmi.c
@@ -2497,7 +2497,7 @@ static int ath12k_qmi_alloc_chunk(struct ath12k_base *ab,
 				    chunk->size,
 				    chunk->type);
 			ath12k_qmi_free_target_mem_chunk(ab);
-			return 0;
+			return -EAGAIN;
 		}
 		ath12k_warn(ab, "memory allocation failure for %u size: %d\n",
 			    chunk->type, chunk->size);
@@ -2600,6 +2600,14 @@ static int ath12k_qmi_alloc_target_mem_chunk(struct ath12k_base *ab)
 
 	mutex_unlock(&ag->mutex);
 
+	/* The firmware will attempt to request memory in smaller chunks
+	 * on the next try. However, the current caller should be notified
+	 * that this instance of request parsing was successful.
+	 * Therefore, return 0 only.
+	 */
+	if (ret == -EAGAIN)
+		ret = 0;
+
 	return ret;
 }
 
-- 
2.39.5