static int ntb_async_tx_submit()

in ntb_transport.c [1799:1856]

• 47 lines of code
• 6 McCabe index (conditional complexity)

static int ntb_async_tx_submit(struct ntb_transport_qp *qp,
			       struct ntb_queue_entry *entry)
{
	struct dma_async_tx_descriptor *txd;
	struct dma_chan *chan = qp->tx_dma_chan;
	struct dma_device *device;
	size_t len = entry->len;
	void *buf = entry->buf;
	size_t dest_off, buff_off;
	struct dmaengine_unmap_data *unmap;
	dma_addr_t dest;
	dma_cookie_t cookie;

	device = chan->device;
	dest = qp->tx_mw_dma_addr + qp->tx_max_frame * entry->tx_index;
	buff_off = (size_t)buf & ~PAGE_MASK;
	dest_off = (size_t)dest & ~PAGE_MASK;

	if (!is_dma_copy_aligned(device, buff_off, dest_off, len))
		goto err;

	unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
	if (!unmap)
		goto err;

	unmap->len = len;
	unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf),
				      buff_off, len, DMA_TO_DEVICE);
	if (dma_mapping_error(device->dev, unmap->addr[0]))
		goto err_get_unmap;

	unmap->to_cnt = 1;

	txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len,
					     DMA_PREP_INTERRUPT);
	if (!txd)
		goto err_get_unmap;

	txd->callback_result = ntb_tx_copy_callback;
	txd->callback_param = entry;
	dma_set_unmap(txd, unmap);

	cookie = dmaengine_submit(txd);
	if (dma_submit_error(cookie))
		goto err_set_unmap;

	dmaengine_unmap_put(unmap);

	dma_async_issue_pending(chan);

	return 0;
err_set_unmap:
	dmaengine_unmap_put(unmap);
err_get_unmap:
	dmaengine_unmap_put(unmap);
err:
	return -ENXIO;
}