C++ (Cpp) mhi_get_free_descの例

コード例 #1

ファイル: msm_rmnet_mhi.c プロジェクト: sztablet2016/Android-kernel-msm-3.10

static int rmnet_mhi_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct rmnet_mhi_private *rmnet_mhi_ptr =
			*(struct rmnet_mhi_private **)netdev_priv(dev);
	enum MHI_STATUS res = MHI_STATUS_reserved;
	unsigned long flags;
	int retry = 0;
	struct mhi_skb_priv *tx_priv;

	rmnet_log(MSG_VERBOSE, "Entered chan %d\n", rmnet_mhi_ptr->tx_channel);

	tx_priv = (struct mhi_skb_priv *)(skb->cb);
	tx_priv->dma_size = skb->len;
	tx_priv->dma_addr = 0;
	do {
		retry = 0;
		res = mhi_queue_xfer(rmnet_mhi_ptr->tx_client_handle,
						    skb->data,
						    skb->len,
						    MHI_EOT);

		if (-ENOSPC == res) {
			write_lock_irqsave(&rmnet_mhi_ptr->out_chan_full_lock,
									flags);
			if (!mhi_get_free_desc(
					    rmnet_mhi_ptr->tx_client_handle)) {
				/* Stop writing until we can write again */
				tx_ring_full_count[rmnet_mhi_ptr->dev_index]++;
				netif_stop_queue(dev);
				rmnet_log(MSG_VERBOSE, "Stopping Queue\n");
				goto rmnet_mhi_xmit_error_cleanup;
			} else {
				retry = 1;
			}
			write_unlock_irqrestore(
					&rmnet_mhi_ptr->out_chan_full_lock,
					flags);
		}
	} while (retry);

	if (MHI_STATUS_SUCCESS != res) {
		netif_stop_queue(dev);
		rmnet_log(MSG_CRITICAL,
			  "mhi_queue_xfer failed, error %d\n", res);
		goto rmnet_mhi_xmit_error_cleanup;
	}

	skb_queue_tail(&(rmnet_mhi_ptr->tx_buffers), skb);

	dev->trans_start = jiffies;

	tx_queued_packets_count[rmnet_mhi_ptr->dev_index]++;
	rmnet_log(MSG_VERBOSE, "Exited\n");
	return 0;

rmnet_mhi_xmit_error_cleanup:
	rmnet_log(MSG_VERBOSE, "Ring full\n");
	write_unlock_irqrestore(&rmnet_mhi_ptr->out_chan_full_lock, flags);
	return NETDEV_TX_BUSY;
}

コード例 #2

ファイル: msm_rmnet_mhi.c プロジェクト: Pafcholini/Beta_TW

static int rmnet_mhi_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct rmnet_mhi_private *rmnet_mhi_ptr =
			*(struct rmnet_mhi_private **)netdev_priv(dev);
	enum MHI_STATUS res = MHI_STATUS_reserved;
	unsigned long flags;
	int retry = 0;
	struct tx_buffer_priv *tx_priv;
	dma_addr_t dma_addr;

	rmnet_log(MSG_VERBOSE, "Entered\n");
	dma_addr = dma_map_single(&(dev->dev), skb->data, skb->len,
				  DMA_TO_DEVICE);
	if (dma_mapping_error(&(dev->dev), dma_addr)) {
			rmnet_log(MSG_CRITICAL,
				"DMA mapping error in transmit function\n");
			return NETDEV_TX_BUSY;
	}

	/* DMA mapping is OK, need to update the cb field properly */
	tx_priv = (struct tx_buffer_priv *)(skb->cb);
	tx_priv->dma_addr = dma_addr;
	do {
		retry = 0;
		res = mhi_queue_xfer(rmnet_mhi_ptr->tx_client_handle,
				     dma_addr, skb->len, MHI_EOT);

		if (MHI_STATUS_RING_FULL == res) {
			write_lock_irqsave(&rmnet_mhi_ptr->out_chan_full_lock,
									flags);
			if (!mhi_get_free_desc(
					    rmnet_mhi_ptr->tx_client_handle)) {
				/* Stop writing until we can write again */
				tx_ring_full_count[rmnet_mhi_ptr->dev_index]++;
				netif_stop_queue(dev);
				goto rmnet_mhi_xmit_error_cleanup;
			} else {
				retry = 1;
			}
			write_unlock_irqrestore(
					&rmnet_mhi_ptr->out_chan_full_lock,
					flags);
		}
	} while (retry);

	if (MHI_STATUS_SUCCESS != res) {
		netif_stop_queue(dev);
		rmnet_log(MSG_CRITICAL,
			  "mhi_queue_xfer failed, error %d\n", res);
		goto rmnet_mhi_xmit_error_cleanup;
	}

	skb_queue_tail(&(rmnet_mhi_ptr->tx_buffers), skb);

	dev->trans_start = jiffies;

	tx_queued_packets_count[rmnet_mhi_ptr->dev_index]++;
	rmnet_log(MSG_VERBOSE, "Exited\n");
	return 0;

rmnet_mhi_xmit_error_cleanup:
	dma_unmap_single(&(dev->dev), dma_addr, skb->len,
			 DMA_TO_DEVICE);
	rmnet_log(MSG_VERBOSE, "Ring full\n");
	write_unlock_irqrestore(&rmnet_mhi_ptr->out_chan_full_lock, flags);
	return NETDEV_TX_BUSY;
}