path: root/drivers/net/ethernet/mellanox/mlx4/en_rx.c

/*
 * Copyright (c) 2007 Mellanox Technologies. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#include <net/busy_poll.h>
#include <linux/mlx4/cq.h>
#include <linux/slab.h>
#include <linux/mlx4/qp.h>
#include <linux/skbuff.h>
#include <linux/rculist.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/vmalloc.h>

#include "mlx4_en.h"

static int mlx4_alloc_pages(struct mlx4_en_priv *priv,
			    struct mlx4_en_rx_alloc *page_alloc,
			    const struct mlx4_en_frag_info *frag_info,
			    gfp_t _gfp)
{
	int order;
	struct page *page;
	dma_addr_t dma;

	for (order = MLX4_EN_ALLOC_PREFER_ORDER; ;) {
		gfp_t gfp = _gfp;

		if (order)
			gfp |= __GFP_COMP | __GFP_NOWARN;
		page = alloc_pages(gfp, order);
		if (likely(page))
			break;
		if (--order < 0 ||
		    ((PAGE_SIZE << order) < frag_info->frag_size))
			return -ENOMEM;
	}
	dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE << order,
			   PCI_DMA_FROMDEVICE);
	if (dma_mapping_error(priv->ddev, dma)) {
		put_page(page);
		return -ENOMEM;
	}
	page_alloc->page_size = PAGE_SIZE << order;
	page_alloc->page = page;
	page_alloc->dma = dma;
	page_alloc->page_offset = frag_info->frag_align;
	/* Not doing get_page() for each frag is a big win
	 * on asymetric workloads.
	 */
	atomic_set(&page->_count,
		   page_alloc->page_size / frag_info->frag_stride);
	return 0;
}

static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv,
			       struct mlx4_en_rx_desc *rx_desc,
			       struct mlx4_en_rx_alloc *frags,
			       struct mlx4_en_rx_alloc *ring_alloc,
			       gfp_t gfp)
{
	struct mlx4_en_rx_alloc page_alloc[MLX4_EN_MAX_RX_FRAGS];
	const struct mlx4_en_frag_info *frag_info;
	struct page *page;
	dma_addr_t dma;
	int i;

	for (i = 0; i < priv->num_frags; i++) {
		frag_info = &priv->frag_info[i];
		page_alloc[i] = ring_alloc[i];
		page_alloc[i].page_offset += frag_info->frag_stride;

		if (page_alloc[i].page_offset + frag_info->frag_stride <=
		    ring_alloc[i].page_size)
			continue;

		if (mlx4_alloc_pages(priv, &page_alloc[i], frag_info, gfp))
			goto out;
	}

	for (i = 0; i < priv->num_frags; i++) {
		frags[i] = ring_alloc[i];
		dma = ring_alloc[i].dma + ring_alloc[i].page_offset;
		ring_alloc[i] = page_alloc[i];
		rx_desc->data[i].addr = cpu_to_be64(dma);
	}

	return 0;

out:
	while (i--) {
		frag_info = &priv->frag_info[i];
		if (page_alloc[i].page != ring_alloc[i].page) {
			dma_unmap_page(priv->ddev, page_alloc[i].dma,
				page_alloc[i].page_size, PCI_DMA_FROMDEVICE);
			page =