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path: root/drivers/net/mlx4/en_tx.c
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Diffstat (limited to 'drivers/net/mlx4/en_tx.c')
-rw-r--r--drivers/net/mlx4/en_tx.c820
1 files changed, 820 insertions, 0 deletions
diff --git a/drivers/net/mlx4/en_tx.c b/drivers/net/mlx4/en_tx.c
new file mode 100644
index 000000000000..8592f8fb8475
--- /dev/null
+++ b/drivers/net/mlx4/en_tx.c
@@ -0,0 +1,820 @@
+/*
+ * 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;
+}
+