xref: /freebsd-11-stable/sys/dev/mlx4/mlx4_en/mlx4_en_rx.c

/*
 * Copyright (c) 2007, 2014 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 "opt_inet.h"
#include <dev/mlx4/cq.h>
#include <linux/slab.h>
#include <dev/mlx4/qp.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/vmalloc.h>
#include <dev/mlx4/driver.h>
#ifdef CONFIG_NET_RX_BUSY_POLL
#include <net/busy_poll.h>
#endif

#include "en.h"

#if (MLX4_EN_MAX_RX_SEGS == 1)
static void mlx4_en_init_rx_desc(struct mlx4_en_priv *priv,
				 struct mlx4_en_rx_ring *ring,
				 int index)
{
	struct mlx4_en_rx_desc *rx_desc =
	    ((struct mlx4_en_rx_desc *)ring->buf) + index;
	int i;

	/* Set size and memtype fields */
	rx_desc->data[0].byte_count = cpu_to_be32(priv->rx_mb_size - MLX4_NET_IP_ALIGN);
	rx_desc->data[0].lkey = cpu_to_be32(priv->mdev->mr.key);

	/*
	 * If the number of used fragments does not fill up the ring
	 * stride, remaining (unused) fragments must be padded with
	 * null address/size and a special memory key:
	 */
	for (i = 1; i < MLX4_EN_MAX_RX_SEGS; i++) {
		rx_desc->data[i].byte_count = 0;
		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
		rx_desc->data[i].addr = 0;
	}
}
#endif

static inline struct mbuf *
mlx4_en_alloc_mbuf(struct mlx4_en_rx_ring *ring)
{
	struct mbuf *mb;

#if (MLX4_EN_MAX_RX_SEGS == 1)
        mb = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, ring->rx_mb_size);
        if (likely(mb != NULL))
		mb->m_pkthdr.len = mb->m_len = ring->rx_mb_size;
#else
	mb = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MLX4_EN_MAX_RX_BYTES);
	if (likely(mb != NULL)) {
		struct mbuf *mb_head = mb;
		int i;

		mb->m_len = MLX4_EN_MAX_RX_BYTES;
		mb->m_pkthdr.len = MLX4_EN_MAX_RX_BYTES;

		for (i = 1; i != MLX4_EN_MAX_RX_SEGS; i++) {
			if (mb_head->m_pkthdr.len >= ring->rx_mb_size)
				break;
			mb = (mb->m_next = m_getjcl(M_NOWAIT, MT_DATA, 0, MLX4_EN_MAX_RX_BYTES));
			if (unlikely(mb == NULL)) {
				m_freem(mb_head);
				return (NULL);
			}
			mb->m_len = MLX4_EN_MAX_RX_BYTES;
			mb_head->m_pkthdr.len += MLX4_EN_MAX_RX_BYTES;
		}
		/* rewind to first mbuf in chain */
		mb = mb_head;
	}
#endif
	return (mb);
}

static int
mlx4_en_alloc_buf(struct mlx4_en_rx_ring *ring, struct mlx4_en_rx_desc *rx_desc,
    struct mlx4_en_rx_mbuf *mb_list)
{
	bus_dma_segment_t segs[MLX4_EN_MAX_RX_SEGS];
	bus_dmamap_t map;
	struct mbuf *mb;
	int nsegs;
	int err;
#if (MLX4_EN_MAX_RX_SEGS != 1)
	int i;
#endif

	/* try to allocate a new spare mbuf */
	if (unlikely(ring->spare.mbuf == NULL)) {
		mb = mlx4_en_alloc_mbuf(ring);
		if (unlikely(mb == NULL))
			return (-ENOMEM);

		/* make sure IP header gets aligned */
		m_adj(mb, MLX4_NET_IP_ALIGN);

		/* load spare mbuf into BUSDMA */
		err = -bus_dmamap_load_mbuf_sg(ring->dma_tag, ring->spare.dma_map,
		    mb, ring->spare.segs, &nsegs, BUS_DMA_NOWAIT);
		if (unlikely(err != 0)) {
			m_freem(mb);
			return (err);
		}

		/* store spare info */
		ring->spare.mbuf = mb;

#if (MLX4_EN_MAX_RX_SEGS != 1)
		/* zero remaining segs */
		for (i = nsegs; i != MLX4_EN_MAX_RX_SEGS; i++) {
			ring->spare.segs[i].ds_addr = 0;
			ring->spare.segs[i].ds_len = 0;
		}
#endif
		bus_dmamap_sync(ring->dma_tag, ring->spare.dma_map,
		    BUS_DMASYNC_PREREAD);
	}

	/* synchronize and unload the current mbuf, if any */
	if (likely(mb_list->mbuf != NULL)) {
		bus_dmamap_sync(ring->dma_tag, mb_list->dma_map,
		    BUS_DMASYNC_POSTREAD);
		bus_dmamap_unload(ring->dma_tag, mb_list->dma_map);
	}

	mb = mlx4_en_alloc_mbuf(ring);
	if (unlikely(mb == NULL))
		goto use_spare;

	/* make sure IP header gets aligned */
	m_adj(mb, MLX4_NET_IP_ALIGN);

	err = -bus_dmamap_load_mbuf_sg(ring->dma_tag, mb_list->dma_map,
	    mb, segs, &nsegs, BUS_DMA_NOWAIT);
	if (unlikely(err != 0)) {
		m_freem(mb);
		goto use_spare;
	}

#if (MLX4_EN_MAX_RX_SEGS == 1)
	rx_desc->data[0].addr = cpu_to_be64(segs[0].ds_addr);
#else
	for (i = 0; i != nsegs; i++) {
		rx_desc->data[i].byte_count = cpu_to_be32(segs[i].ds_len);
		rx_desc->data[i].lkey = ring->rx_mr_key_be;
		rx_desc->data[i].addr = cpu_to_be64(segs[i].ds_addr);
	}
	for (; i != MLX4_EN_MAX_RX_SEGS; i++) {
		rx_desc->data[i].byte_count = 0;
		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
		rx_desc->data[i].addr = 0;
	}
#endif
	mb_list->mbuf = mb;

	bus_dmamap_sync(ring->dma_tag, mb_list->dma_map, BUS_DMASYNC_PREREAD);
	return (0);

use_spare:
	/* swap DMA maps */
	map = mb_list->dma_map;
	mb_list->dma_map = ring->spare.dma_map;
	ring->spare.dma_map = map;

	/* swap MBUFs */
	mb_list->mbuf = ring->spare.mbuf;
	ring->spare.mbuf = NULL;

	/* store physical address */
#if (MLX4_EN_MAX_RX_SEGS == 1)
	rx_desc->data[0].addr = cpu_to_be64(ring->spare.segs[0].ds_addr);
#else
	for (i = 0; i != MLX4_EN_MAX_RX_SEGS; i++) {
		if (ring->spare.segs[i].ds_len != 0) {
			rx_desc->data[i].byte_count = cpu_to_be32(ring->spare.segs[i].ds_len);
			rx_desc->data[i].lkey = ring->rx_mr_key_be;
			rx_desc->data[i].addr = cpu_to_be64(ring->spare.segs[i].ds_addr);
		} else {
			rx_desc->data[i].byte_count = 0;
			rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
			rx_desc->data[i].addr = 0;
		}
	}
#endif
	return (0);
}

static void
mlx4_en_free_buf(struct mlx4_en_rx_ring *ring, struct mlx4_en_rx_mbuf *mb_list)
{
	bus_dmamap_t map = mb_list->dma_map;
	bus_dmamap_sync(ring->dma_tag, map, BUS_DMASYNC_POSTREAD);
	bus_dmamap_unload(ring->dma_tag, map);
	m_freem(mb_list->mbuf);
	mb_list->mbuf = NULL;	/* safety clearing */
}

static int
mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
    struct mlx4_en_rx_ring *ring, int index)
{
	struct mlx4_en_rx_desc *rx_desc =
	    ((struct mlx4_en_rx_desc *)ring->buf) + index;
	struct mlx4_en_rx_mbuf *mb_list = ring->mbuf + index;

	mb_list->mbuf = NULL;

	if (mlx4_en_alloc_buf(ring, rx_desc, mb_list)) {
		priv->port_stats.rx_alloc_failed++;
		return (-ENOMEM);
	}
	return (0);
}

static inline void
mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
{
	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
}

static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
{
	struct mlx4_en_rx_ring *ring;
	int ring_ind;
	int buf_ind;
	int new_size;
	int err;

	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
			ring = priv->rx_ring[ring_ind];

			err = mlx4_en_prepare_rx_desc(priv, ring,
						      ring->actual_size);
			if (err) {
				if (ring->actual_size == 0) {
					en_err(priv, "Failed to allocate "
						     "enough rx buffers\n");
					return -ENOMEM;
				} else {
					new_size =
						rounddown_pow_of_two(ring->actual_size);
					en_warn(priv, "Only %d buffers allocated "
						      "reducing ring size to %d\n",
						ring->actual_size, new_size);
					goto reduce_rings;
				}
			}
			ring->actual_size++;
			ring->prod++;
		}
	}
	return 0;

reduce_rings:
	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
		ring = priv->rx_ring[ring_ind];
		while (ring->actual_size > new_size) {
			ring->actual_size--;
			ring->prod--;
			mlx4_en_free_buf(ring,
			    ring->mbuf + ring->actual_size);
		}
	}

	return 0;
}

static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
				struct mlx4_en_rx_ring *ring)
{
	int index;

	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
	       ring->cons, ring->prod);

	/* Unmap and free Rx buffers */
	BUG_ON((u32) (ring->prod - ring->cons) > ring->actual_size);
	while (ring->cons != ring->prod) {
		index = ring->cons & ring->size_mask;
		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
		mlx4_en_free_buf(ring, ring->mbuf + index);
		++ring->cons;
	}
}

void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev)
{
	int i;
	int num_of_eqs;
	int num_rx_rings;
	struct mlx4_dev *dev = mdev->dev;

	mlx4_foreach_port(i, dev, MLX4_PORT_TYPE_ETH) {
		num_of_eqs = max_t(int, MIN_RX_RINGS,
				   min_t(int,
					 mlx4_get_eqs_per_port(mdev->dev, i),
					 DEF_RX_RINGS));

		num_rx_rings = mlx4_low_memory_profile() ? MIN_RX_RINGS :
							   num_of_eqs;
		mdev->profile.prof[i].rx_ring_num =
			rounddown_pow_of_two(num_rx_rings);
	}
}

void mlx4_en_calc_rx_buf(struct net_device *dev)
{
	struct mlx4_en_priv *priv = netdev_priv(dev);
	int eff_mtu = dev->if_mtu + ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN +
	    MLX4_NET_IP_ALIGN;

	if (eff_mtu > MJUM16BYTES) {
		en_err(priv, "MTU(%u) is too big\n", (unsigned)dev->if_mtu);
                eff_mtu = MJUM16BYTES;
        } else if (eff_mtu > MJUM9BYTES) {
                eff_mtu = MJUM16BYTES;
        } else if (eff_mtu > MJUMPAGESIZE) {
                eff_mtu = MJUM9BYTES;
        } else if (eff_mtu > MCLBYTES) {
                eff_mtu = MJUMPAGESIZE;
        } else {
                eff_mtu = MCLBYTES;
        }

	priv->rx_mb_size = eff_mtu;

	en_dbg(DRV, priv, "Effective RX MTU: %d bytes\n", eff_mtu);
}

int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
			   struct mlx4_en_rx_ring **pring,
			   u32 size, int node)
{
	struct mlx4_en_dev *mdev = priv->mdev;
	struct mlx4_en_rx_ring *ring;
	int err;
	int tmp;
	uint32_t x;

        ring = kzalloc(sizeof(struct mlx4_en_rx_ring), GFP_KERNEL);
        if (!ring) {
                en_err(priv, "Failed to allocate RX ring structure\n");
                return -ENOMEM;
        }

	/* Create DMA descriptor TAG */
	if ((err = -bus_dma_tag_create(
	    bus_get_dma_tag(mdev->pdev->dev.bsddev),
	    1,				/* any alignment */
	    0,				/* no boundary */
	    BUS_SPACE_MAXADDR,		/* lowaddr */
	    BUS_SPACE_MAXADDR,		/* highaddr */
	    NULL, NULL,			/* filter, filterarg */
	    MJUM16BYTES,		/* maxsize */
	    MLX4_EN_MAX_RX_SEGS,	/* nsegments */
	    MJUM16BYTES,		/* maxsegsize */
	    0,				/* flags */
	    NULL, NULL,			/* lockfunc, lockfuncarg */
	    &ring->dma_tag))) {
		en_err(priv, "Failed to create DMA tag\n");
		goto err_ring;
	}

	ring->prod = 0;
	ring->cons = 0;
	ring->size = size;
	ring->size_mask = size - 1;

	ring->log_stride = ilog2(sizeof(struct mlx4_en_rx_desc));
	ring->buf_size = (ring->size * sizeof(struct mlx4_en_rx_desc)) + TXBB_SIZE;

	tmp = size * sizeof(struct mlx4_en_rx_mbuf);

        ring->mbuf = kzalloc(tmp, GFP_KERNEL);
        if (ring->mbuf == NULL) {
                err = -ENOMEM;
                goto err_dma_tag;
        }

	err = -bus_dmamap_create(ring->dma_tag, 0, &ring->spare.dma_map);
	if (err != 0)
		goto err_info;

	for (x = 0; x != size; x++) {
		err = -bus_dmamap_create(ring->dma_tag, 0,
		    &ring->mbuf[x].dma_map);
		if (err != 0) {
			while (x--)
				bus_dmamap_destroy(ring->dma_tag,
				    ring->mbuf[x].dma_map);
			goto err_info;
		}
	}
	en_dbg(DRV, priv, "Allocated MBUF ring at addr:%p size:%d\n",
		 ring->mbuf, tmp);

	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres,
				 ring->buf_size, 2 * PAGE_SIZE);
	if (err)
		goto err_dma_map;

	err = mlx4_en_map_buffer(&ring->wqres.buf);
	if (err) {
		en_err(priv, "Failed to map RX buffer\n");
		goto err_hwq;
	}
	ring->buf = ring->wqres.buf.direct.buf;
	*pring = ring;
	return 0;

err_hwq:
	mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
err_dma_map:
	for (x = 0; x != size; x++) {
		bus_dmamap_destroy(ring->dma_tag,
		    ring->mbuf[x].dma_map);
	}
	bus_dmamap_destroy(ring->dma_tag, ring->spare.dma_map);
err_info:
	vfree(ring->mbuf);
err_dma_tag:
	bus_dma_tag_destroy(ring->dma_tag);
err_ring:
	kfree(ring);
	return (err);
}

int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
{
	struct mlx4_en_rx_ring *ring;
#if (MLX4_EN_MAX_RX_SEGS == 1)
	int i;
#endif
	int ring_ind;
	int err;

	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
		ring = priv->rx_ring[ring_ind];

		ring->prod = 0;
		ring->cons = 0;
		ring->actual_size = 0;
		ring->cqn = priv->rx_cq[ring_ind]->mcq.cqn;
                ring->rx_mb_size = priv->rx_mb_size;

		if (sizeof(struct mlx4_en_rx_desc) <= TXBB_SIZE) {
			/* Stamp first unused send wqe */
			__be32 *ptr = (__be32 *)ring->buf;
			__be32 stamp = cpu_to_be32(1 << STAMP_SHIFT);
			*ptr = stamp;
			/* Move pointer to start of rx section */
			ring->buf += TXBB_SIZE;
		}

		ring->log_stride = ilog2(sizeof(struct mlx4_en_rx_desc));
		ring->buf_size = ring->size * sizeof(struct mlx4_en_rx_desc);

		memset(ring->buf, 0, ring->buf_size);
		mlx4_en_update_rx_prod_db(ring);

#if (MLX4_EN_MAX_RX_SEGS == 1)
		/* Initialize all descriptors */
		for (i = 0; i < ring->size; i++)
			mlx4_en_init_rx_desc(priv, ring, i);
#endif
		ring->rx_mr_key_be = cpu_to_be32(priv->mdev->mr.key);

#ifdef INET
		/* Configure lro mngr */
		if (priv->dev->if_capenable & IFCAP_LRO) {
			if (tcp_lro_init(&ring->lro))
				priv->dev->if_capenable &= ~IFCAP_LRO;
			else
				ring->lro.ifp = priv->dev;
		}
#endif
	}


	err = mlx4_en_fill_rx_buffers(priv);
	if (err)
		goto err_buffers;

	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
		ring = priv->rx_ring[ring_ind];

		ring->size_mask = ring->actual_size - 1;
		mlx4_en_update_rx_prod_db(ring);
	}

	return 0;

err_buffers:
	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
		mlx4_en_free_rx_buf(priv, priv->rx_ring[ring_ind]);

	ring_ind = priv->rx_ring_num - 1;

	while (ring_ind >= 0) {
		ring = priv->rx_ring[ring_ind];
		if (sizeof(struct mlx4_en_rx_desc) <= TXBB_SIZE)
			ring->buf -= TXBB_SIZE;
		ring_ind--;
	}

	return err;
}


void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
			     struct mlx4_en_rx_ring **pring,
			     u32 size)
{
	struct mlx4_en_dev *mdev = priv->mdev;
	struct mlx4_en_rx_ring *ring = *pring;
	uint32_t x;

	mlx4_en_unmap_buffer(&ring->wqres.buf);
	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * sizeof(struct mlx4_en_rx_desc) + TXBB_SIZE);
	for (x = 0; x != size; x++)
		bus_dmamap_destroy(ring->dma_tag, ring->mbuf[x].dma_map);
	/* free spare mbuf, if any */
	if (ring->spare.mbuf != NULL) {
		bus_dmamap_sync(ring->dma_tag, ring->spare.dma_map,
		    BUS_DMASYNC_POSTREAD);
		bus_dmamap_unload(ring->dma_tag, ring->spare.dma_map);
		m_freem(ring->spare.mbuf);
	}
	bus_dmamap_destroy(ring->dma_tag, ring->spare.dma_map);
	vfree(ring->mbuf);
	bus_dma_tag_destroy(ring->dma_tag);
	kfree(ring);
	*pring = NULL;
#ifdef CONFIG_RFS_ACCEL
	mlx4_en_cleanup_filters(priv, ring);
#endif
}

void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
				struct mlx4_en_rx_ring *ring)
{
#ifdef INET
	tcp_lro_free(&ring->lro);
#endif
	mlx4_en_free_rx_buf(priv, ring);
	if (sizeof(struct mlx4_en_rx_desc) <= TXBB_SIZE)
		ring->buf -= TXBB_SIZE;
}


static void validate_loopback(struct mlx4_en_priv *priv, struct mbuf *mb)
{
	int i;
	int offset = ETHER_HDR_LEN;

	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++, offset++) {
		if (*(mb->m_data + offset) != (unsigned char) (i & 0xff))
			goto out_loopback;
	}
	/* Loopback found */
	priv->loopback_ok = 1;

out_loopback:
	m_freem(mb);
}


static inline int invalid_cqe(struct mlx4_en_priv *priv,
			      struct mlx4_cqe *cqe)
{
	/* Drop packet on bad receive or bad checksum */
	if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
		     MLX4_CQE_OPCODE_ERROR)) {
		en_err(priv, "CQE completed in error - vendor syndrom:%d syndrom:%d\n",
		       ((struct mlx4_err_cqe *)cqe)->vendor_err_syndrome,
		       ((struct mlx4_err_cqe *)cqe)->syndrome);
		return 1;
	}
	if (unlikely(cqe->badfcs_enc & MLX4_CQE_BAD_FCS)) {
		en_dbg(RX_ERR, priv, "Accepted frame with bad FCS\n");
		return 1;
	}

	return 0;
}

static struct mbuf *
mlx4_en_rx_mb(struct mlx4_en_priv *priv, struct mlx4_en_rx_ring *ring,
    struct mlx4_en_rx_desc *rx_desc, struct mlx4_en_rx_mbuf *mb_list,
    int length)
{
#if (MLX4_EN_MAX_RX_SEGS != 1)
	struct mbuf *mb_head;
#endif
	struct mbuf *mb;

	/* optimise reception of small packets */
	if (length <= (MHLEN - MLX4_NET_IP_ALIGN) &&
	    (mb = m_gethdr(M_NOWAIT, MT_DATA)) != NULL) {

		/* set packet length */
		mb->m_pkthdr.len = mb->m_len = length;

		/* make sure IP header gets aligned */
		mb->m_data += MLX4_NET_IP_ALIGN;

		bus_dmamap_sync(ring->dma_tag, mb_list->dma_map,
		    BUS_DMASYNC_POSTREAD);

		bcopy(mtod(mb_list->mbuf, caddr_t), mtod(mb, caddr_t), length);

		return (mb);
	}

	/* get mbuf */
	mb = mb_list->mbuf;

	/* collect used fragment while atomically replacing it */
	if (mlx4_en_alloc_buf(ring, rx_desc, mb_list))
		return (NULL);

	/* range check hardware computed value */
	if (unlikely(length > mb->m_pkthdr.len))
		length = mb->m_pkthdr.len;

#if (MLX4_EN_MAX_RX_SEGS == 1)
	/* update total packet length in packet header */
	mb->m_len = mb->m_pkthdr.len = length;
#else
	mb->m_pkthdr.len = length;
	for (mb_head = mb; mb != NULL; mb = mb->m_next) {
		if (mb->m_len > length)
			mb->m_len = length;
		length -= mb->m_len;
		if (likely(length == 0)) {
			if (likely(mb->m_next != NULL)) {
				/* trim off empty mbufs */
				m_freem(mb->m_next);
				mb->m_next = NULL;
			}
			break;
		}
	}
	/* rewind to first mbuf in chain */
	mb = mb_head;
#endif
	return (mb);
}

static __inline int
mlx4_en_rss_hash(__be16 status, int udp_rss)
{
	enum {
		status_all = cpu_to_be16(
			MLX4_CQE_STATUS_IPV4    |
			MLX4_CQE_STATUS_IPV4F   |
			MLX4_CQE_STATUS_IPV6    |
			MLX4_CQE_STATUS_TCP     |
			MLX4_CQE_STATUS_UDP),
		status_ipv4_tcp = cpu_to_be16(
			MLX4_CQE_STATUS_IPV4    |
			MLX4_CQE_STATUS_TCP),
		status_ipv6_tcp = cpu_to_be16(
			MLX4_CQE_STATUS_IPV6    |
			MLX4_CQE_STATUS_TCP),
		status_ipv4_udp = cpu_to_be16(
			MLX4_CQE_STATUS_IPV4    |
			MLX4_CQE_STATUS_UDP),
		status_ipv6_udp = cpu_to_be16(
			MLX4_CQE_STATUS_IPV6    |
			MLX4_CQE_STATUS_UDP),
		status_ipv4 = cpu_to_be16(MLX4_CQE_STATUS_IPV4),
		status_ipv6 = cpu_to_be16(MLX4_CQE_STATUS_IPV6)
	};

	status &= status_all;
	switch (status) {
	case status_ipv4_tcp:
		return (M_HASHTYPE_RSS_TCP_IPV4);
	case status_ipv6_tcp:
		return (M_HASHTYPE_RSS_TCP_IPV6);
	case status_ipv4_udp:
		return (udp_rss ? M_HASHTYPE_RSS_UDP_IPV4
		    : M_HASHTYPE_RSS_IPV4);
	case status_ipv6_udp:
		return (udp_rss ? M_HASHTYPE_RSS_UDP_IPV6
		    : M_HASHTYPE_RSS_IPV6);
	default:
		if (status & status_ipv4)
			return (M_HASHTYPE_RSS_IPV4);
		if (status & status_ipv6)
			return (M_HASHTYPE_RSS_IPV6);
		return (M_HASHTYPE_OPAQUE_HASH);
	}
}

/* For cpu arch with cache line of 64B the performance is better when cqe size==64B
 * To enlarge cqe size from 32B to 64B --> 32B of garbage (i.e. 0xccccccc)
 * was added in the beginning of each cqe (the real data is in the corresponding 32B).
 * The following calc ensures that when factor==1, it means we are aligned to 64B
 * and we get the real cqe data*/
#define CQE_FACTOR_INDEX(index, factor) (((index) << (factor)) + (factor))
int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
{
	struct mlx4_en_priv *priv = netdev_priv(dev);
	struct mlx4_cqe *cqe;
	struct mlx4_en_rx_ring *ring = priv->rx_ring[cq->ring];
	struct mlx4_en_rx_mbuf *mb_list;
	struct mlx4_en_rx_desc *rx_desc;
	struct mbuf *mb;
	struct mlx4_cq *mcq = &cq->mcq;
	struct mlx4_cqe *buf = cq->buf;
	int index;
	unsigned int length;
	int polled = 0;
	u32 cons_index = mcq->cons_index;
	u32 size_mask = ring->size_mask;
	int size = cq->size;
	int factor = priv->cqe_factor;
	const int udp_rss = priv->mdev->profile.udp_rss;

	if (!priv->port_up)
		return 0;

	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
	 * descriptor offset can be deducted from the CQE index instead of
	 * reading 'cqe->index' */
	index = cons_index & size_mask;
	cqe = &buf[CQE_FACTOR_INDEX(index, factor)];

	/* Process all completed CQEs */
	while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
		    cons_index & size)) {
		mb_list = ring->mbuf + index;
		rx_desc = ((struct mlx4_en_rx_desc *)ring->buf) + index;

		/*
		 * make sure we read the CQE after we read the ownership bit
		 */
		rmb();

		if (invalid_cqe(priv, cqe)) {
			goto next;
		}
		/*
		 * Packet is OK - process it.
		 */
		length = be32_to_cpu(cqe->byte_cnt);
		length -= ring->fcs_del;

		mb = mlx4_en_rx_mb(priv, ring, rx_desc, mb_list, length);
		if (unlikely(!mb)) {
			ring->errors++;
			goto next;
		}

		ring->bytes += length;
		ring->packets++;

		if (unlikely(priv->validate_loopback)) {
			validate_loopback(priv, mb);
			goto next;
		}

		/* forward Toeplitz compatible hash value */
		mb->m_pkthdr.flowid = be32_to_cpu(cqe->immed_rss_invalid);
		M_HASHTYPE_SET(mb, mlx4_en_rss_hash(cqe->status, udp_rss));
		mb->m_pkthdr.rcvif = dev;
		if (be32_to_cpu(cqe->vlan_my_qpn) &
		    MLX4_CQE_CVLAN_PRESENT_MASK) {
			mb->m_pkthdr.ether_vtag = be16_to_cpu(cqe->sl_vid);
			mb->m_flags |= M_VLANTAG;
		}
		if (likely(dev->if_capenable &
		    (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6)) &&
		    (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
		    (cqe->checksum == cpu_to_be16(0xffff))) {
			priv->port_stats.rx_chksum_good++;
			mb->m_pkthdr.csum_flags =
			    CSUM_IP_CHECKED | CSUM_IP_VALID |
			    CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
			mb->m_pkthdr.csum_data = htons(0xffff);
			/* This packet is eligible for LRO if it is:
			 * - DIX Ethernet (type interpretation)
			 * - TCP/IP (v4)
			 * - without IP options
			 * - not an IP fragment
			 */
#ifdef INET
			if (mlx4_en_can_lro(cqe->status) &&
					(dev->if_capenable & IFCAP_LRO)) {
				if (ring->lro.lro_cnt != 0 &&
						tcp_lro_rx(&ring->lro, mb, 0) == 0)
					goto next;
			}

#endif
			/* LRO not possible, complete processing here */
			INC_PERF_COUNTER(priv->pstats.lro_misses);
		} else {
			mb->m_pkthdr.csum_flags = 0;
			priv->port_stats.rx_chksum_none++;
		}

		/* Push it up the stack */
		dev->if_input(dev, mb);

next:
		++cons_index;
		index = cons_index & size_mask;
		cqe = &buf[CQE_FACTOR_INDEX(index, factor)];
		if (++polled == budget)
			goto out;
	}
	/* Flush all pending IP reassembly sessions */
out:
#ifdef INET
	tcp_lro_flush_all(&ring->lro);
#endif
	AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
	mcq->cons_index = cons_index;
	mlx4_cq_set_ci(mcq);
	wmb(); /* ensure HW sees CQ consumer before we post new buffers */
	ring->cons = mcq->cons_index;
	ring->prod += polled; /* Polled descriptors were realocated in place */
	mlx4_en_update_rx_prod_db(ring);
	return polled;

}

/* Rx CQ polling - called by NAPI */
static int mlx4_en_poll_rx_cq(struct mlx4_en_cq *cq, int budget)
{
        struct net_device *dev = cq->dev;
        int done;

        done = mlx4_en_process_rx_cq(dev, cq, budget);
        cq->tot_rx += done;

        return done;

}
void mlx4_en_rx_irq(struct mlx4_cq *mcq)
{
	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
        int done;

        // Shoot one within the irq context
        // Because there is no NAPI in freeBSD
        done = mlx4_en_poll_rx_cq(cq, MLX4_EN_RX_BUDGET);
	if (priv->port_up  && (done == MLX4_EN_RX_BUDGET) ) {
		cq->curr_poll_rx_cpu_id = curcpu;
		taskqueue_enqueue(cq->tq, &cq->cq_task);
        }
	else {
		mlx4_en_arm_cq(priv, cq);
	}
}

void mlx4_en_rx_que(void *context, int pending)
{
        struct mlx4_en_cq *cq;
	struct thread *td;

        cq = context;
	td = curthread;

	thread_lock(td);
	sched_bind(td, cq->curr_poll_rx_cpu_id);
	thread_unlock(td);

        while (mlx4_en_poll_rx_cq(cq, MLX4_EN_RX_BUDGET)
                        == MLX4_EN_RX_BUDGET);
        mlx4_en_arm_cq(cq->dev->if_softc, cq);
}


/* RSS related functions */

static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
				 struct mlx4_en_rx_ring *ring,
				 enum mlx4_qp_state *state,
				 struct mlx4_qp *qp)
{
	struct mlx4_en_dev *mdev = priv->mdev;
	struct mlx4_qp_context *context;
	int err = 0;

	context = kmalloc(sizeof *context , GFP_KERNEL);
	if (!context) {
		en_err(priv, "Failed to allocate qp context\n");
		return -ENOMEM;
	}

	err = mlx4_qp_alloc(mdev->dev, qpn, qp, GFP_KERNEL);
	if (err) {
		en_err(priv, "Failed to allocate qp #%x\n", qpn);
		goto out;
	}
	qp->event = mlx4_en_sqp_event;

	memset(context, 0, sizeof *context);
	mlx4_en_fill_qp_context(priv, ring->actual_size, sizeof(struct mlx4_en_rx_desc), 0, 0,
				qpn, ring->cqn, -1, context);
	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);

	/* Cancel FCS removal if FW allows */
	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
		context->param3 |= cpu_to_be32(1 << 29);
		ring->fcs_del = ETH_FCS_LEN;
	} else
		ring->fcs_del = 0;

	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
	if (err) {
		mlx4_qp_remove(mdev->dev, qp);
		mlx4_qp_free(mdev->dev, qp);
	}
	mlx4_en_update_rx_prod_db(ring);
out:
	kfree(context);
	return err;
}

int mlx4_en_create_drop_qp(struct mlx4_en_priv *priv)
{
	int err;
	u32 qpn;

	err = mlx4_qp_reserve_range(priv->mdev->dev, 1, 1, &qpn, 0);
	if (err) {
		en_err(priv, "Failed reserving drop qpn\n");
		return err;
	}
	err = mlx4_qp_alloc(priv->mdev->dev, qpn, &priv->drop_qp, GFP_KERNEL);
	if (err) {
		en_err(priv, "Failed allocating drop qp\n");
		mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
		return err;
	}

	return 0;
}

void mlx4_en_destroy_drop_qp(struct mlx4_en_priv *priv)
{
	u32 qpn;

	qpn = priv->drop_qp.qpn;
	mlx4_qp_remove(priv->mdev->dev, &priv->drop_qp);
	mlx4_qp_free(priv->mdev->dev, &priv->drop_qp);
	mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
}

const u32 *
mlx4_en_get_rss_key(struct mlx4_en_priv *priv __unused,
    u16 *keylen)
{
	static const u32 rsskey[10] = {
		cpu_to_be32(0xD181C62C),
		cpu_to_be32(0xF7F4DB5B),
		cpu_to_be32(0x1983A2FC),
		cpu_to_be32(0x943E1ADB),
		cpu_to_be32(0xD9389E6B),
		cpu_to_be32(0xD1039C2C),
		cpu_to_be32(0xA74499AD),
		cpu_to_be32(0x593D56D9),
		cpu_to_be32(0xF3253C06),
		cpu_to_be32(0x2ADC1FFC)
	};

	if (keylen != NULL)
		*keylen = sizeof(rsskey);
	return (rsskey);
}

u8 mlx4_en_get_rss_mask(struct mlx4_en_priv *priv)
{
	u8 rss_mask = (MLX4_RSS_IPV4 | MLX4_RSS_TCP_IPV4 | MLX4_RSS_IPV6 |
			MLX4_RSS_TCP_IPV6);

	if (priv->mdev->profile.udp_rss)
		rss_mask |=  MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6;
	return (rss_mask);
}

/* Allocate rx qp's and configure them according to rss map */
int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
{
	struct mlx4_en_dev *mdev = priv->mdev;
	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
	struct mlx4_qp_context context;
	struct mlx4_rss_context *rss_context;
	const u32 *key;
	int rss_rings;
	void *ptr;
	int i;
	int err = 0;
	int good_qps = 0;

	en_dbg(DRV, priv, "Configuring rss steering\n");
	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
				    priv->rx_ring_num,
				    &rss_map->base_qpn, 0);
	if (err) {
		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
		return err;
	}

	for (i = 0; i < priv->rx_ring_num; i++) {
		priv->rx_ring[i]->qpn = rss_map->base_qpn + i;
		err = mlx4_en_config_rss_qp(priv, priv->rx_ring[i]->qpn,
					    priv->rx_ring[i],
					    &rss_map->state[i],
					    &rss_map->qps[i]);
		if (err)
			goto rss_err;

		++good_qps;
	}

	/* Configure RSS indirection qp */
	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp, GFP_KERNEL);
	if (err) {
		en_err(priv, "Failed to allocate RSS indirection QP\n");
		goto rss_err;
	}
	rss_map->indir_qp.event = mlx4_en_sqp_event;
	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
				priv->rx_ring[0]->cqn, -1, &context);

	if (!priv->prof->rss_rings || priv->prof->rss_rings > priv->rx_ring_num)
		rss_rings = priv->rx_ring_num;
	else
		rss_rings = priv->prof->rss_rings;

	ptr = ((u8 *)&context) + offsetof(struct mlx4_qp_context, pri_path) +
	    MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
	rss_context = ptr;
	rss_context->base_qpn = cpu_to_be32(ilog2(rss_rings) << 24 |
					    (rss_map->base_qpn));
	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
	if (priv->mdev->profile.udp_rss)
		rss_context->base_qpn_udp = rss_context->default_qpn;
	rss_context->flags = mlx4_en_get_rss_mask(priv);
	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
	key = mlx4_en_get_rss_key(priv, NULL);
	for (i = 0; i < 10; i++)
		rss_context->rss_key[i] = key[i];

	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
			       &rss_map->indir_qp, &rss_map->indir_state);
	if (err)
		goto indir_err;

	return 0;

indir_err:
	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
rss_err:
	for (i = 0; i < good_qps; i++) {
		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
	}
	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
	return err;
}

void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
{
	struct mlx4_en_dev *mdev = priv->mdev;
	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
	int i;

	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);

	for (i = 0; i < priv->rx_ring_num; i++) {
		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
	}
	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
}