1 files changed, 35 insertions, 23 deletions

diff --git a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c
index 26017fe..801ba07 100644
--- a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c
+++ b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c
@@ -718,6 +718,23 @@ static int set_tx_csum(struct dpaa2_eth_priv *priv, bool enable)
 	return 0;
 }
 
+/* Free buffers acquired from the buffer pool or which were meant to
+ * be released in the pool
+ */
+static void free_bufs(struct dpaa2_eth_priv *priv, u64 *buf_array, int count)
+{
+	struct device *dev = priv->net_dev->dev.parent;
+	void *vaddr;
+	int i;
+
+	for (i = 0; i < count; i++) {
+		vaddr = dpaa2_iova_to_virt(priv->iommu_domain, buf_array[i]);
+		dma_unmap_single(dev, buf_array[i], DPAA2_ETH_RX_BUF_SIZE,
+				 DMA_BIDIRECTIONAL);
+		skb_free_frag(vaddr);
+	}
+}
+
 /* Perform a single release command to add buffers
  * to the specified buffer pool
  */
@@ -727,7 +744,7 @@ static int add_bufs(struct dpaa2_eth_priv *priv, u16 bpid)
 	u64 buf_array[DPAA2_ETH_BUFS_PER_CMD];
 	void *buf;
 	dma_addr_t addr;
-	int i;
+	int i, err;
 
 	for (i = 0; i < DPAA2_ETH_BUFS_PER_CMD; i++) {
 		/* Allocate buffer visible to WRIOP + skb shared info +
@@ -754,22 +771,27 @@ static int add_bufs(struct dpaa2_eth_priv *priv, u16 bpid)
 	}
 
 release_bufs:
-	/* In case the portal is busy, retry until successful.
-	 * The buffer release function would only fail if the QBMan portal
-	 * was busy, which implies portal contention (i.e. more CPUs than
-	 * portals, i.e. GPPs w/o affine DPIOs). For all practical purposes,
-	 * there is little we can realistically do, short of giving up -
-	 * in which case we'd risk depleting the buffer pool and never again
-	 * receiving the Rx interrupt which would kick-start the refill logic.
-	 * So just keep retrying, at the risk of being moved to ksoftirqd.
-	 */
-	while (dpaa2_io_service_release(NULL, bpid, buf_array, i))
+	/* In case the portal is busy, retry until successful */
+	while ((err = dpaa2_io_service_release(NULL, bpid,
+					       buf_array, i)) == -EBUSY)
 		cpu_relax();
+
+	/* If release command failed, clean up and bail out;
+	 * not much else we can do about it
+	 */
+	if (err) {
+		free_bufs(priv, buf_array, i);
+		return 0;
+	}
+
 	return i;
 
 err_map:
 	skb_free_frag(buf);
 err_alloc:
+	/* If we managed to allocate at least some buffers,
+	 * release them to hardware
+	 */
 	if (i)
 		goto release_bufs;
 
@@ -811,10 +833,8 @@ static int seed_pool(struct dpaa2_eth_priv *priv, u16 bpid)
  */
 static void drain_bufs(struct dpaa2_eth_priv *priv, int count)
 {
-	struct device *dev = priv->net_dev->dev.parent;
 	u64 buf_array[DPAA2_ETH_BUFS_PER_CMD];
-	void *vaddr;
-	int ret, i;
+	int ret;
 
 	do {
 		ret = dpaa2_io_service_acquire(NULL, priv->bpid,
@@ -823,15 +843,7 @@ static void drain_bufs(struct dpaa2_eth_priv *priv, int count)
 			netdev_err(priv->net_dev, "dpaa2_io_service_acquire() failed\n");
 			return;
 		}
-		for (i = 0; i < ret; i++) {
-			/* Same logic as on regular Rx path */
-			vaddr = dpaa2_iova_to_virt(priv->iommu_domain,
-						   buf_array[i]);
-			dma_unmap_single(dev, buf_array[i],
-					 DPAA2_ETH_RX_BUF_SIZE,
-					 DMA_FROM_DEVICE);
-			skb_free_frag(vaddr);
-		}
+		free_bufs(priv, buf_array, ret);
 	} while (ret);
 }