blob: 8592f8fb847577c42ed5b964ff50be35b1e6840a [file] [log] [blame]
/*
* 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 <asm/page.h>
#include <linux/mlx4/cq.h>
#include <linux/mlx4/qp.h>
#include <linux/skbuff.h>
#include <linux/if_vlan.h>
#include <linux/vmalloc.h>
#include "mlx4_en.h"
enum {
MAX_INLINE = 104, /* 128 - 16 - 4 - 4 */
};
static int inline_thold __read_mostly = MAX_INLINE;
module_param_named(inline_thold, inline_thold, int, 0444);
MODULE_PARM_DESC(inline_thold, "treshold for using inline data");
int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring, u32 size,
u16 stride)
{
struct mlx4_en_dev *mdev = priv->mdev;
int tmp;
int err;
ring->size = size;
ring->size_mask = size - 1;
ring->stride = stride;
inline_thold = min(inline_thold, MAX_INLINE);
spin_lock_init(&ring->comp_lock);
tmp = size * sizeof(struct mlx4_en_tx_info);
ring->tx_info = vmalloc(tmp);
if (!ring->tx_info) {
mlx4_err(mdev, "Failed allocating tx_info ring\n");
return -ENOMEM;
}
mlx4_dbg(DRV, priv, "Allocated tx_info ring at addr:%p size:%d\n",
ring->tx_info, tmp);
ring->bounce_buf = kmalloc(MAX_DESC_SIZE, GFP_KERNEL);
if (!ring->bounce_buf) {
mlx4_err(mdev, "Failed allocating bounce buffer\n");
err = -ENOMEM;
goto err_tx;
}
ring->buf_size = ALIGN(size * ring->stride, MLX4_EN_PAGE_SIZE);
err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres, ring->buf_size,
2 * PAGE_SIZE);
if (err) {
mlx4_err(mdev, "Failed allocating hwq resources\n");
goto err_bounce;
}
err = mlx4_en_map_buffer(&ring->wqres.buf);
if (err) {
mlx4_err(mdev, "Failed to map TX buffer\n");
goto err_hwq_res;
}
ring->buf = ring->wqres.buf.direct.buf;
mlx4_dbg(DRV, priv, "Allocated TX ring (addr:%p) - buf:%p size:%d "
"buf_size:%d dma:%llx\n", ring, ring->buf, ring->size,
ring->buf_size, (unsigned long long) ring->wqres.buf.direct.map);
err = mlx4_qp_reserve_range(mdev->dev, 1, 1, &ring->qpn);
if (err) {
mlx4_err(mdev, "Failed reserving qp for tx ring.\n");
goto err_map;
}
err = mlx4_qp_alloc(mdev->dev, ring->qpn, &ring->qp);
if (err) {
mlx4_err(mdev, "Failed allocating qp %d\n", ring->qpn);
goto err_reserve;
}
return 0;
err_reserve:
mlx4_qp_release_range(mdev->dev, ring->qpn, 1);
err_map:
mlx4_en_unmap_buffer(&ring->wqres.buf);
err_hwq_res:
mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
err_bounce:
kfree(ring->bounce_buf);
ring->bounce_buf = NULL;
err_tx:
vfree(ring->tx_info);
ring->tx_info = NULL;
return err;
}
void mlx4_en_destroy_tx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring)
{
struct mlx4_en_dev *mdev = priv->mdev;
mlx4_dbg(DRV, priv, "Destroying tx ring, qpn: %d\n", ring->qpn);
mlx4_qp_remove(mdev->dev, &ring->qp);
mlx4_qp_free(mdev->dev, &ring->qp);
mlx4_qp_release_range(mdev->dev, ring->qpn, 1);
mlx4_en_unmap_buffer(&ring->wqres.buf);
mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
kfree(ring->bounce_buf);
ring->bounce_buf = NULL;
vfree(ring->tx_info);
ring->tx_info = NULL;
}
int mlx4_en_activate_tx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring,
int cq, int srqn)
{
struct mlx4_en_dev *mdev = priv->mdev;
int err;
ring->cqn = cq;
ring->prod = 0;
ring->cons = 0xffffffff;
ring->last_nr_txbb = 1;
ring->poll_cnt = 0;
ring->blocked = 0;
memset(ring->tx_info, 0, ring->size * sizeof(struct mlx4_en_tx_info));
memset(ring->buf, 0, ring->buf_size);
ring->qp_state = MLX4_QP_STATE_RST;
ring->doorbell_qpn = swab32(ring->qp.qpn << 8);
mlx4_en_fill_qp_context(priv, ring->size, ring->stride, 1, 0, ring->qpn,
ring->cqn, srqn, &ring->context);
err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, &ring->context,
&ring->qp, &ring->qp_state);
return err;
}
void mlx4_en_deactivate_tx_ring(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring)
{
struct mlx4_en_dev *mdev = priv->mdev;
mlx4_qp_modify(mdev->dev, NULL, ring->qp_state,
MLX4_QP_STATE_RST, NULL, 0, 0, &ring->qp);
}
static u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring,
int index, u8 owner)
{
struct mlx4_en_dev *mdev = priv->mdev;
struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
struct mlx4_en_tx_desc *tx_desc = ring->buf + index * TXBB_SIZE;
struct mlx4_wqe_data_seg *data = (void *) tx_desc + tx_info->data_offset;
struct sk_buff *skb = tx_info->skb;
struct skb_frag_struct *frag;
void *end = ring->buf + ring->buf_size;
int frags = skb_shinfo(skb)->nr_frags;
int i;
__be32 *ptr = (__be32 *)tx_desc;
__be32 stamp = cpu_to_be32(STAMP_VAL | (!!owner << STAMP_SHIFT));
/* Optimize the common case when there are no wraparounds */
if (likely((void *) tx_desc + tx_info->nr_txbb * TXBB_SIZE <= end)) {
if (tx_info->linear) {
pci_unmap_single(mdev->pdev,
(dma_addr_t) be64_to_cpu(data->addr),
be32_to_cpu(data->byte_count),
PCI_DMA_TODEVICE);
++data;
}
for (i = 0; i < frags; i++) {
frag = &skb_shinfo(skb)->frags[i];
pci_unmap_page(mdev->pdev,
(dma_addr_t) be64_to_cpu(data[i].addr),
frag->size, PCI_DMA_TODEVICE);
}
/* Stamp the freed descriptor */
for (i = 0; i < tx_info->nr_txbb * TXBB_SIZE; i += STAMP_STRIDE) {
*ptr = stamp;
ptr += STAMP_DWORDS;
}
} else {
if ((void *) data >= end) {
data = (struct mlx4_wqe_data_seg *)
(ring->buf + ((void *) data - end));
}
if (tx_info->linear) {
pci_unmap_single(mdev->pdev,
(dma_addr_t) be64_to_cpu(data->addr),
be32_to_cpu(data->byte_count),
PCI_DMA_TODEVICE);
++data;
}
for (i = 0; i < frags; i++) {
/* Check for wraparound before unmapping */
if ((void *) data >= end)
data = (struct mlx4_wqe_data_seg *) ring->buf;
frag = &skb_shinfo(skb)->frags[i];
pci_unmap_page(mdev->pdev,
(dma_addr_t) be64_to_cpu(data->addr),
frag->size, PCI_DMA_TODEVICE);
}
/* Stamp the freed descriptor */
for (i = 0; i < tx_info->nr_txbb * TXBB_SIZE; i += STAMP_STRIDE) {
*ptr = stamp;
ptr += STAMP_DWORDS;
if ((void *) ptr >= end) {
ptr = ring->buf;
stamp ^= cpu_to_be32(0x80000000);
}
}
}
dev_kfree_skb_any(skb);
return tx_info->nr_txbb;
}
int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring)
{
struct mlx4_en_priv *priv = netdev_priv(dev);
int cnt = 0;
/* Skip last polled descriptor */
ring->cons += ring->last_nr_txbb;
mlx4_dbg(DRV, priv, "Freeing Tx buf - cons:0x%x prod:0x%x\n",
ring->cons, ring->prod);
if ((u32) (ring->prod - ring->cons) > ring->size) {
if (netif_msg_tx_err(priv))
mlx4_warn(priv->mdev, "Tx consumer passed producer!\n");
return 0;
}
while (ring->cons != ring->prod) {
ring->last_nr_txbb = mlx4_en_free_tx_desc(priv, ring,
ring->cons & ring->size_mask,
!!(ring->cons & ring->size));
ring->cons += ring->last_nr_txbb;
cnt++;
}
if (cnt)
mlx4_dbg(DRV, priv, "Freed %d uncompleted tx descriptors\n", cnt);
return cnt;
}
void mlx4_en_set_prio_map(struct mlx4_en_priv *priv, u16 *prio_map, u32 ring_num)
{
int block = 8 / ring_num;
int extra = 8 - (block * ring_num);
int num = 0;
u16 ring = 1;
int prio;
if (ring_num == 1) {
for (prio = 0; prio < 8; prio++)
prio_map[prio] = 0;
return;
}
for (prio = 0; prio < 8; prio++) {
if (extra && (num == block + 1)) {
ring++;
num = 0;
extra--;
} else if (!extra && (num == block)) {
ring++;
num = 0;
}
prio_map[prio] = ring;
mlx4_dbg(DRV, priv, " prio:%d --> ring:%d\n", prio, ring);
num++;
}
}
static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
{
struct mlx4_en_priv *priv = netdev_priv(dev);
struct mlx4_cq *mcq = &cq->mcq;
struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
struct mlx4_cqe *cqe = cq->buf;
u16 index;
u16 new_index;
u32 txbbs_skipped = 0;
u32 cq_last_sav;
/* index always points to the first TXBB of the last polled descriptor */
index = ring->cons & ring->size_mask;
new_index = be16_to_cpu(cqe->wqe_index) & ring->size_mask;
if (index == new_index)
return;
if (!priv->port_up)
return;
/*
* We use a two-stage loop:
* - the first samples the HW-updated CQE
* - the second frees TXBBs until the last sample
* This lets us amortize CQE cache misses, while still polling the CQ
* until is quiescent.
*/
cq_last_sav = mcq->cons_index;
do {
do {
/* Skip over last polled CQE */
index = (index + ring->last_nr_txbb) & ring->size_mask;
txbbs_skipped += ring->last_nr_txbb;
/* Poll next CQE */
ring->last_nr_txbb = mlx4_en_free_tx_desc(
priv, ring, index,
!!((ring->cons + txbbs_skipped) &
ring->size));
++mcq->cons_index;
} while (index != new_index);
new_index = be16_to_cpu(cqe->wqe_index) & ring->size_mask;
} while (index != new_index);
AVG_PERF_COUNTER(priv->pstats.tx_coal_avg,
(u32) (mcq->cons_index - cq_last_sav));
/*
* To prevent CQ overflow we first update CQ consumer and only then
* the ring consumer.
*/
mlx4_cq_set_ci(mcq);
wmb();
ring->cons += txbbs_skipped;
/* Wakeup Tx queue if this ring stopped it */
if (unlikely(ring->blocked)) {
if (((u32) (ring->prod - ring->cons) <=
ring->size - HEADROOM - MAX_DESC_TXBBS) && !cq->armed) {
/* TODO: support multiqueue netdevs. Currently, we block
* when *any* ring is full. Note that:
* - 2 Tx rings can unblock at the same time and call
* netif_wake_queue(), which is OK since this
* operation is idempotent.
* - We might wake the queue just after another ring
* stopped it. This is no big deal because the next
* transmission on that ring would stop the queue.
*/
ring->blocked = 0;
netif_wake_queue(dev);
priv->port_stats.wake_queue++;
}
}
}
void mlx4_en_tx_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);
struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
spin_lock_irq(&ring->comp_lock);
cq->armed = 0;
mlx4_en_process_tx_cq(cq->dev, cq);
if (ring->blocked)
mlx4_en_arm_cq(priv, cq);
else
mod_timer(&cq->timer, jiffies + 1);
spin_unlock_irq(&ring->comp_lock);
}
void mlx4_en_poll_tx_cq(unsigned long data)
{
struct mlx4_en_cq *cq = (struct mlx4_en_cq *) data;
struct mlx4_en_priv *priv = netdev_priv(cq->dev);
struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
u32 inflight;
INC_PERF_COUNTER(priv->pstats.tx_poll);
netif_tx_lock(priv->dev);
spin_lock_irq(&ring->comp_lock);
mlx4_en_process_tx_cq(cq->dev, cq);
inflight = (u32) (ring->prod - ring->cons - ring->last_nr_txbb);
/* If there are still packets in flight and the timer has not already
* been scheduled by the Tx routine then schedule it here to guarantee
* completion processing of these packets */
if (inflight && priv->port_up)
mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
spin_unlock_irq(&ring->comp_lock);
netif_tx_unlock(priv->dev);
}
static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
struct mlx4_en_tx_ring *ring,
u32 index,
unsigned int desc_size)
{
u32 copy = (ring->size - index) * TXBB_SIZE;
int i;
for (i = desc_size - copy - 4; i >= 0; i -= 4) {
if ((i & (TXBB_SIZE - 1)) == 0)
wmb();
*((u32 *) (ring->buf + i)) =
*((u32 *) (ring->bounce_buf + copy + i));
}
for (i = copy - 4; i >= 4 ; i -= 4) {
if ((i & (TXBB_SIZE - 1)) == 0)
wmb();
*((u32 *) (ring->buf + index * TXBB_SIZE + i)) =
*((u32 *) (ring->bounce_buf + i));
}
/* Return real descriptor location */
return ring->buf + index * TXBB_SIZE;
}
static inline void mlx4_en_xmit_poll(struct mlx4_en_priv *priv, int tx_ind)
{
struct mlx4_en_cq *cq = &priv->tx_cq[tx_ind];
struct mlx4_en_tx_ring *ring = &priv->tx_ring[tx_ind];
/* If we don't have a pending timer, set one up to catch our recent
post in case the interface becomes idle */
if (!timer_pending(&cq->timer))
mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
/* Poll the CQ every mlx4_en_TX_MODER_POLL packets */
if ((++ring->poll_cnt & (MLX4_EN_TX_POLL_MODER - 1)) == 0)
mlx4_en_process_tx_cq(priv->dev, cq);
}
static void *get_frag_ptr(struct sk_buff *skb)
{
struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0];
struct page *page = frag->page;
void *ptr;
ptr = page_address(page);
if (unlikely(!ptr))
return NULL;
return ptr + frag->page_offset;
}
static int is_inline(struct sk_buff *skb, void **pfrag)
{
void *ptr;
if (inline_thold && !skb_is_gso(skb) && skb->len <= inline_thold) {
if (skb_shinfo(skb)->nr_frags == 1) {
ptr = get_frag_ptr(skb);
if (unlikely(!ptr))
return 0;
if (pfrag)
*pfrag = ptr;
return 1;
} else if (unlikely(skb_shinfo(skb)->nr_frags))
return 0;
else
return 1;
}
return 0;
}
static int inline_size(struct sk_buff *skb)
{
if (skb->len + CTRL_SIZE + sizeof(struct mlx4_wqe_inline_seg)
<= MLX4_INLINE_ALIGN)
return ALIGN(skb->len + CTRL_SIZE +
sizeof(struct mlx4_wqe_inline_seg), 16);
else
return ALIGN(skb->len + CTRL_SIZE + 2 *
sizeof(struct mlx4_wqe_inline_seg), 16);
}
static int get_real_size(struct sk_buff *skb, struct net_device *dev,
int *lso_header_size)
{
struct mlx4_en_priv *priv = netdev_priv(dev);
struct mlx4_en_dev *mdev = priv->mdev;
int real_size;
if (skb_is_gso(skb)) {
*lso_header_size = skb_transport_offset(skb) + tcp_hdrlen(skb);
real_size = CTRL_SIZE + skb_shinfo(skb)->nr_frags * DS_SIZE +
ALIGN(*lso_header_size + 4, DS_SIZE);
if (unlikely(*lso_header_size != skb_headlen(skb))) {
/* We add a segment for the skb linear buffer only if
* it contains data */
if (*lso_header_size < skb_headlen(skb))
real_size += DS_SIZE;
else {
if (netif_msg_tx_err(priv))
mlx4_warn(mdev, "Non-linear headers\n");
dev_kfree_skb_any(skb);
return 0;
}
}
if (unlikely(*lso_header_size > MAX_LSO_HDR_SIZE)) {
if (netif_msg_tx_err(priv))
mlx4_warn(mdev, "LSO header size too big\n");
dev_kfree_skb_any(skb);
return 0;
}
} else {
*lso_header_size = 0;
if (!is_inline(skb, NULL))
real_size = CTRL_SIZE + (skb_shinfo(skb)->nr_frags + 1) * DS_SIZE;
else
real_size = inline_size(skb);
}
return real_size;
}
static void build_inline_wqe(struct mlx4_en_tx_desc *tx_desc, struct sk_buff *skb,
int real_size, u16 *vlan_tag, int tx_ind, void *fragptr)
{
struct mlx4_wqe_inline_seg *inl = &tx_desc->inl;
int spc = MLX4_INLINE_ALIGN - CTRL_SIZE - sizeof *inl;
if (skb->len <= spc) {
inl->byte_count = cpu_to_be32(1 << 31 | skb->len);
skb_copy_from_linear_data(skb, inl + 1, skb_headlen(skb));
if (skb_shinfo(skb)->nr_frags)
memcpy(((void *)(inl + 1)) + skb_headlen(skb), fragptr,
skb_shinfo(skb)->frags[0].size);
} else {
inl->byte_count = cpu_to_be32(1 << 31 | spc);
if (skb_headlen(skb) <= spc) {
skb_copy_from_linear_data(skb, inl + 1, skb_headlen(skb));
if (skb_headlen(skb) < spc) {
memcpy(((void *)(inl + 1)) + skb_headlen(skb),
fragptr, spc - skb_headlen(skb));
fragptr += spc - skb_headlen(skb);
}
inl = (void *) (inl + 1) + spc;
memcpy(((void *)(inl + 1)), fragptr, skb->len - spc);
} else {
skb_copy_from_linear_data(skb, inl + 1, spc);
inl = (void *) (inl + 1) + spc;
skb_copy_from_linear_data_offset(skb, spc, inl + 1,
skb_headlen(skb) - spc);
if (skb_shinfo(skb)->nr_frags)
memcpy(((void *)(inl + 1)) + skb_headlen(skb) - spc,
fragptr, skb_shinfo(skb)->frags[0].size);
}
wmb();
inl->byte_count = cpu_to_be32(1 << 31 | (skb->len - spc));
}
tx_desc->ctrl.vlan_tag = cpu_to_be16(*vlan_tag);
tx_desc->ctrl.ins_vlan = MLX4_WQE_CTRL_INS_VLAN * !!(*vlan_tag);
tx_desc->ctrl.fence_size = (real_size / 16) & 0x3f;
}
static int get_vlan_info(struct mlx4_en_priv *priv, struct sk_buff *skb,
u16 *vlan_tag)
{
int tx_ind;
/* Obtain VLAN information if present */
if (priv->vlgrp && vlan_tx_tag_present(skb)) {
*vlan_tag = vlan_tx_tag_get(skb);
/* Set the Tx ring to use according to vlan priority */
tx_ind = priv->tx_prio_map[*vlan_tag >> 13];
} else {
*vlan_tag = 0;
tx_ind = 0;
}
return tx_ind;
}
int mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct mlx4_en_priv *priv = netdev_priv(dev);
struct mlx4_en_dev *mdev = priv->mdev;
struct mlx4_en_tx_ring *ring;
struct mlx4_en_cq *cq;
struct mlx4_en_tx_desc *tx_desc;
struct mlx4_wqe_data_seg *data;
struct skb_frag_struct *frag;
struct mlx4_en_tx_info *tx_info;
int tx_ind = 0;
int nr_txbb;
int desc_size;
int real_size;
dma_addr_t dma;
u32 index;
__be32 op_own;
u16 vlan_tag;
int i;
int lso_header_size;
void *fragptr;
if (unlikely(!skb->len)) {
dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
real_size = get_real_size(skb, dev, &lso_header_size);
if (unlikely(!real_size))
return NETDEV_TX_OK;
/* Allign descriptor to TXBB size */
desc_size = ALIGN(real_size, TXBB_SIZE);
nr_txbb = desc_size / TXBB_SIZE;
if (unlikely(nr_txbb > MAX_DESC_TXBBS)) {
if (netif_msg_tx_err(priv))
mlx4_warn(mdev, "Oversized header or SG list\n");
dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
tx_ind = get_vlan_info(priv, skb, &vlan_tag);
ring = &priv->tx_ring[tx_ind];
/* Check available TXBBs And 2K spare for prefetch */
if (unlikely(((int)(ring->prod - ring->cons)) >
ring->size - HEADROOM - MAX_DESC_TXBBS)) {
/* every full Tx ring stops queue.
* TODO: implement multi-queue support (per-queue stop) */
netif_stop_queue(dev);
ring->blocked = 1;
priv->port_stats.queue_stopped++;
/* Use interrupts to find out when queue opened */
cq = &priv->tx_cq[tx_ind];
mlx4_en_arm_cq(priv, cq);
return NETDEV_TX_BUSY;
}
/* Now that we know what Tx ring to use */
if (unlikely(!priv->port_up)) {
if (netif_msg_tx_err(priv))
mlx4_warn(mdev, "xmit: port down!\n");
dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
/* Track current inflight packets for performance analysis */
AVG_PERF_COUNTER(priv->pstats.inflight_avg,
(u32) (ring->prod - ring->cons - 1));
/* Packet is good - grab an index and transmit it */
index = ring->prod & ring->size_mask;
/* See if we have enough space for whole descriptor TXBB for setting
* SW ownership on next descriptor; if not, use a bounce buffer. */
if (likely(index + nr_txbb <= ring->size))
tx_desc = ring->buf + index * TXBB_SIZE;
else
tx_desc = (struct mlx4_en_tx_desc *) ring->bounce_buf;
/* Save skb in tx_info ring */
tx_info = &ring->tx_info[index];
tx_info->skb = skb;
tx_info->nr_txbb = nr_txbb;
/* Prepare ctrl segement apart opcode+ownership, which depends on
* whether LSO is used */
tx_desc->ctrl.vlan_tag = cpu_to_be16(vlan_tag);
tx_desc->ctrl.ins_vlan = MLX4_WQE_CTRL_INS_VLAN * !!vlan_tag;
tx_desc->ctrl.fence_size = (real_size / 16) & 0x3f;
tx_desc->ctrl.srcrb_flags = cpu_to_be32(MLX4_WQE_CTRL_CQ_UPDATE |
MLX4_WQE_CTRL_SOLICITED);
if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM |
MLX4_WQE_CTRL_TCP_UDP_CSUM);
priv->port_stats.tx_chksum_offload++;
}
/* Handle LSO (TSO) packets */
if (lso_header_size) {
/* Mark opcode as LSO */
op_own = cpu_to_be32(MLX4_OPCODE_LSO | (1 << 6)) |
((ring->prod & ring->size) ?
cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
/* Fill in the LSO prefix */
tx_desc->lso.mss_hdr_size = cpu_to_be32(
skb_shinfo(skb)->gso_size << 16 | lso_header_size);
/* Copy headers;
* note that we already verified that it is linear */
memcpy(tx_desc->lso.header, skb->data, lso_header_size);
data = ((void *) &tx_desc->lso +
ALIGN(lso_header_size + 4, DS_SIZE));
priv->port_stats.tso_packets++;
i = ((skb->len - lso_header_size) / skb_shinfo(skb)->gso_size) +
!!((skb->len - lso_header_size) % skb_shinfo(skb)->gso_size);
ring->bytes += skb->len + (i - 1) * lso_header_size;
ring->packets += i;
} else {
/* Normal (Non LSO) packet */
op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
((ring->prod & ring->size) ?
cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
data = &tx_desc->data;
ring->bytes += max(skb->len, (unsigned int) ETH_ZLEN);
ring->packets++;
}
AVG_PERF_COUNTER(priv->pstats.tx_pktsz_avg, skb->len);
/* valid only for none inline segments */
tx_info->data_offset = (void *) data - (void *) tx_desc;
tx_info->linear = (lso_header_size < skb_headlen(skb) && !is_inline(skb, NULL)) ? 1 : 0;
data += skb_shinfo(skb)->nr_frags + tx_info->linear - 1;
if (!is_inline(skb, &fragptr)) {
/* Map fragments */
for (i = skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) {
frag = &skb_shinfo(skb)->frags[i];
dma = pci_map_page(mdev->dev->pdev, frag->page, frag->page_offset,
frag->size, PCI_DMA_TODEVICE);
data->addr = cpu_to_be64(dma);
data->lkey = cpu_to_be32(mdev->mr.key);
wmb();
data->byte_count = cpu_to_be32(frag->size);
--data;
}
/* Map linear part */
if (tx_info->linear) {
dma = pci_map_single(mdev->dev->pdev, skb->data + lso_header_size,
skb_headlen(skb) - lso_header_size, PCI_DMA_TODEVICE);
data->addr = cpu_to_be64(dma);
data->lkey = cpu_to_be32(mdev->mr.key);
wmb();
data->byte_count = cpu_to_be32(skb_headlen(skb) - lso_header_size);
}
} else
build_inline_wqe(tx_desc, skb, real_size, &vlan_tag, tx_ind, fragptr);
ring->prod += nr_txbb;
/* If we used a bounce buffer then copy descriptor back into place */
if (tx_desc == (struct mlx4_en_tx_desc *) ring->bounce_buf)
tx_desc = mlx4_en_bounce_to_desc(priv, ring, index, desc_size);
/* Run destructor before passing skb to HW */
if (likely(!skb_shared(skb)))
skb_orphan(skb);
/* Ensure new descirptor hits memory
* before setting ownership of this descriptor to HW */
wmb();
tx_desc->ctrl.owner_opcode = op_own;
/* Ring doorbell! */
wmb();
writel(ring->doorbell_qpn, mdev->uar_map + MLX4_SEND_DOORBELL);
dev->trans_start = jiffies;
/* Poll CQ here */
mlx4_en_xmit_poll(priv, tx_ind);
return 0;
}