示例#1
0
文件: rx.c 项目: AppEngine/linux-2.6
void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
{
	int i;
	struct efx_rx_buffer *rx_buf;

	EFX_LOG(rx_queue->efx, "shutting down RX queue %d\n", rx_queue->queue);

	falcon_fini_rx(rx_queue);

	/* Release RX buffers NB start at index 0 not current HW ptr */
	if (rx_queue->buffer) {
		for (i = 0; i <= rx_queue->efx->type->rxd_ring_mask; i++) {
			rx_buf = efx_rx_buffer(rx_queue, i);
			efx_fini_rx_buffer(rx_queue, rx_buf);
		}
	}

	/* For a page that is part-way through splitting into RX buffers */
	if (rx_queue->buf_page != NULL) {
		pci_unmap_page(rx_queue->efx->pci_dev, rx_queue->buf_dma_addr,
			       efx_rx_buf_size(rx_queue->efx),
			       PCI_DMA_FROMDEVICE);
		__free_pages(rx_queue->buf_page,
			     rx_queue->efx->rx_buffer_order);
		rx_queue->buf_page = NULL;
	}
}
示例#2
0
/**
 * efx_init_rx_buffers_page - create EFX_RX_BATCH page-based RX buffers
 *
 * @rx_queue:		Efx RX queue
 *
 * This allocates memory for EFX_RX_BATCH receive buffers, maps them for DMA,
 * and populates struct efx_rx_buffers for each one. Return a negative error
 * code or 0 on success. If a single page can be split between two buffers,
 * then the page will either be inserted fully, or not at at all.
 */
static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
{
	struct efx_nic *efx = rx_queue->efx;
	struct efx_rx_buffer *rx_buf;
	struct page *page;
	void *page_addr;
	unsigned int page_offset;
	struct efx_rx_page_state *state;
	dma_addr_t dma_addr;
	unsigned index, count;

	/* We can split a page between two buffers */
	BUILD_BUG_ON(EFX_RX_BATCH & 1);

	for (count = 0; count < EFX_RX_BATCH; ++count) {
		page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
				   efx->rx_buffer_order);
		if (unlikely(page == NULL))
			return -ENOMEM;
		dma_addr = pci_map_page(efx->pci_dev, page, 0,
					efx_rx_buf_size(efx),
					PCI_DMA_FROMDEVICE);
		if (unlikely(pci_dma_mapping_error(efx->pci_dev, dma_addr))) {
			__free_pages(page, efx->rx_buffer_order);
			return -EIO;
		}
		page_addr = page_address(page);
		state = page_addr;
		state->refcnt = 0;
		state->dma_addr = dma_addr;

		page_addr += sizeof(struct efx_rx_page_state);
		dma_addr += sizeof(struct efx_rx_page_state);
		page_offset = sizeof(struct efx_rx_page_state);

	split:
		index = rx_queue->added_count & rx_queue->ptr_mask;
		rx_buf = efx_rx_buffer(rx_queue, index);
		rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
		rx_buf->u.page = page;
		rx_buf->page_offset = page_offset + EFX_PAGE_IP_ALIGN;
		rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
		rx_buf->is_page = true;
		++rx_queue->added_count;
		++rx_queue->alloc_page_count;
		++state->refcnt;

		if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) {
			/* Use the second half of the page */
			get_page(page);
			dma_addr += (PAGE_SIZE >> 1);
			page_addr += (PAGE_SIZE >> 1);
			page_offset += (PAGE_SIZE >> 1);
			++count;
			goto split;
		}
	}
示例#3
0
文件: rx.c 项目: AppEngine/linux-2.6
static void efx_unmap_rx_buffer(struct efx_nic *efx,
				struct efx_rx_buffer *rx_buf)
{
	if (rx_buf->page) {
		EFX_BUG_ON_PARANOID(rx_buf->skb);
		if (rx_buf->unmap_addr) {
			pci_unmap_page(efx->pci_dev, rx_buf->unmap_addr,
				       efx_rx_buf_size(efx),
				       PCI_DMA_FROMDEVICE);
			rx_buf->unmap_addr = 0;
		}
	} else if (likely(rx_buf->skb)) {
		pci_unmap_single(efx->pci_dev, rx_buf->dma_addr,
				 rx_buf->len, PCI_DMA_FROMDEVICE);
	}
}
示例#4
0
文件: rx.c 项目: AppEngine/linux-2.6
/**
 * efx_init_rx_buffer_page - create new RX buffer using page-based allocation
 *
 * @rx_queue:		Efx RX queue
 * @rx_buf:		RX buffer structure to populate
 *
 * This allocates memory for a new receive buffer, maps it for DMA,
 * and populates a struct efx_rx_buffer with the relevant
 * information.  Return a negative error code or 0 on success.
 */
static int efx_init_rx_buffer_page(struct efx_rx_queue *rx_queue,
				   struct efx_rx_buffer *rx_buf)
{
	struct efx_nic *efx = rx_queue->efx;
	int bytes, space, offset;

	bytes = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;

	/* If there is space left in the previously allocated page,
	 * then use it. Otherwise allocate a new one */
	rx_buf->page = rx_queue->buf_page;
	if (rx_buf->page == NULL) {
		dma_addr_t dma_addr;

		rx_buf->page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
					   efx->rx_buffer_order);
		if (unlikely(rx_buf->page == NULL))
			return -ENOMEM;

		dma_addr = pci_map_page(efx->pci_dev, rx_buf->page,
					0, efx_rx_buf_size(efx),
					PCI_DMA_FROMDEVICE);

		if (unlikely(pci_dma_mapping_error(efx->pci_dev, dma_addr))) {
			__free_pages(rx_buf->page, efx->rx_buffer_order);
			rx_buf->page = NULL;
			return -EIO;
		}

		rx_queue->buf_page = rx_buf->page;
		rx_queue->buf_dma_addr = dma_addr;
		rx_queue->buf_data = (page_address(rx_buf->page) +
				      EFX_PAGE_IP_ALIGN);
	}

	rx_buf->len = bytes;
	rx_buf->data = rx_queue->buf_data;
	offset = efx_rx_buf_offset(rx_buf);
	rx_buf->dma_addr = rx_queue->buf_dma_addr + offset;

	/* Try to pack multiple buffers per page */
	if (efx->rx_buffer_order == 0) {
		/* The next buffer starts on the next 512 byte boundary */
		rx_queue->buf_data += ((bytes + 0x1ff) & ~0x1ff);
		offset += ((bytes + 0x1ff) & ~0x1ff);

		space = efx_rx_buf_size(efx) - offset;
		if (space >= bytes) {
			/* Refs dropped on kernel releasing each skb */
			get_page(rx_queue->buf_page);
			goto out;
		}
	}

	/* This is the final RX buffer for this page, so mark it for
	 * unmapping */
	rx_queue->buf_page = NULL;
	rx_buf->unmap_addr = rx_queue->buf_dma_addr;

 out:
	return 0;
}