drivers/net/mlx4/en_tx.c

   1 /*
   2  * Copyright (c) 2007 Mellanox Technologies. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  *
  32  */
  33
  34 #include <asm/page.h>
  35 #include <linux/mlx4/cq.h>
  36 #include <linux/slab.h>
  37 #include <linux/mlx4/qp.h>
  38 #include <linux/skbuff.h>
  39 #include <linux/if_vlan.h>
  40 #include <linux/vmalloc.h>
  41 #include <linux/tcp.h>
  42
  43 #include "mlx4_en.h"
  44
  45 enum {
  46         MAX_INLINE = 104, /* 128 - 16 - 4 - 4 */
  47         MAX_BF = 256,
  48 };
  49
  50 static int inline_thold __read_mostly = MAX_INLINE;
  51
  52 module_param_named(inline_thold, inline_thold, int, 0444);
  53 MODULE_PARM_DESC(inline_thold, "threshold for using inline data");
  54
  55 int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv,
  56                            struct mlx4_en_tx_ring *ring, int qpn, u32 size,
  57                            u16 stride)
  58 {
  59         struct mlx4_en_dev *mdev = priv->mdev;
  60         int tmp;
  61         int err;
  62
  63         ring->size = size;
  64         ring->size_mask = size - 1;
  65         ring->stride = stride;
  66
  67         inline_thold = min(inline_thold, MAX_INLINE);
  68
  69         spin_lock_init(&ring->comp_lock);
  70
  71         tmp = size * sizeof(struct mlx4_en_tx_info);
  72         ring->tx_info = vmalloc(tmp);
  73         if (!ring->tx_info) {
  74                 en_err(priv, "Failed allocating tx_info ring\n");
  75                 return -ENOMEM;
  76         }
  77         en_dbg(DRV, priv, "Allocated tx_info ring at addr:%p size:%d\n",
  78                  ring->tx_info, tmp);
  79
  80         ring->bounce_buf = kmalloc(MAX_DESC_SIZE, GFP_KERNEL);
  81         if (!ring->bounce_buf) {
  82                 en_err(priv, "Failed allocating bounce buffer\n");
  83                 err = -ENOMEM;
  84                 goto err_tx;
  85         }
  86         ring->buf_size = ALIGN(size * ring->stride, MLX4_EN_PAGE_SIZE);
  87
  88         err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres, ring->buf_size,
  89                                  2 * PAGE_SIZE);
  90         if (err) {
  91                 en_err(priv, "Failed allocating hwq resources\n");
  92                 goto err_bounce;
  93         }
  94
  95         err = mlx4_en_map_buffer(&ring->wqres.buf);
  96         if (err) {
  97                 en_err(priv, "Failed to map TX buffer\n");
  98                 goto err_hwq_res;
  99         }
 100
 101         ring->buf = ring->wqres.buf.direct.buf;
 102
 103         en_dbg(DRV, priv, "Allocated TX ring (addr:%p) - buf:%p size:%d "
 104                "buf_size:%d dma:%llx\n", ring, ring->buf, ring->size,
 105                ring->buf_size, (unsigned long long) ring->wqres.buf.direct.map);
 106
 107         ring->qpn = qpn;
 108         err = mlx4_qp_alloc(mdev->dev, ring->qpn, &ring->qp);
 109         if (err) {
 110                 en_err(priv, "Failed allocating qp %d\n", ring->qpn);
 111                 goto err_map;
 112         }
 113         ring->qp.event = mlx4_en_sqp_event;
 114
 115         err = mlx4_bf_alloc(mdev->dev, &ring->bf);
 116         if (err) {
 117                 en_dbg(DRV, priv, "working without blueflame (%d)", err);
 118                 ring->bf.uar = &mdev->priv_uar;
 119                 ring->bf.uar->map = mdev->uar_map;
 120                 ring->bf_enabled = false;
 121         } else
 122                 ring->bf_enabled = true;
 123
 124         return 0;
 125
 126 err_map:
 127         mlx4_en_unmap_buffer(&ring->wqres.buf);
 128 err_hwq_res:
 129         mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
 130 err_bounce:
 131         kfree(ring->bounce_buf);
 132         ring->bounce_buf = NULL;
 133 err_tx:
 134         vfree(ring->tx_info);
 135         ring->tx_info = NULL;
 136         return err;
 137 }
 138
 139 void mlx4_en_destroy_tx_ring(struct mlx4_en_priv *priv,
 140                              struct mlx4_en_tx_ring *ring)
 141 {
 142         struct mlx4_en_dev *mdev = priv->mdev;
 143         en_dbg(DRV, priv, "Destroying tx ring, qpn: %d\n", ring->qpn);
 144
 145         if (ring->bf_enabled)
 146                 mlx4_bf_free(mdev->dev, &ring->bf);
 147         mlx4_qp_remove(mdev->dev, &ring->qp);
 148         mlx4_qp_free(mdev->dev, &ring->qp);
 149         mlx4_qp_release_range(mdev->dev, ring->qpn, 1);
 150         mlx4_en_unmap_buffer(&ring->wqres.buf);
 151         mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
 152         kfree(ring->bounce_buf);
 153         ring->bounce_buf = NULL;
 154         vfree(ring->tx_info);
 155         ring->tx_info = NULL;
 156 }
 157
 158 int mlx4_en_activate_tx_ring(struct mlx4_en_priv *priv,
 159                              struct mlx4_en_tx_ring *ring,
 160                              int cq)
 161 {
 162         struct mlx4_en_dev *mdev = priv->mdev;
 163         int err;
 164
 165         ring->cqn = cq;
 166         ring->prod = 0;
 167         ring->cons = 0xffffffff;
 168         ring->last_nr_txbb = 1;
 169         ring->poll_cnt = 0;
 170         ring->blocked = 0;
 171         memset(ring->tx_info, 0, ring->size * sizeof(struct mlx4_en_tx_info));
 172         memset(ring->buf, 0, ring->buf_size);
 173
 174         ring->qp_state = MLX4_QP_STATE_RST;
 175         ring->doorbell_qpn = swab32(ring->qp.qpn << 8);
 176
 177         mlx4_en_fill_qp_context(priv, ring->size, ring->stride, 1, 0, ring->qpn,
 178                                 ring->cqn, &ring->context);
 179         if (ring->bf_enabled)
 180                 ring->context.usr_page = cpu_to_be32(ring->bf.uar->index);
 181
 182         err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, &ring->context,
 183                                &ring->qp, &ring->qp_state);
 184
 185         return err;
 186 }
 187
 188 void mlx4_en_deactivate_tx_ring(struct mlx4_en_priv *priv,
 189                                 struct mlx4_en_tx_ring *ring)
 190 {
 191         struct mlx4_en_dev *mdev = priv->mdev;
 192
 193         mlx4_qp_modify(mdev->dev, NULL, ring->qp_state,
 194                        MLX4_QP_STATE_RST, NULL, 0, 0, &ring->qp);
 195 }
 196
 197
 198 static u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
 199                                 struct mlx4_en_tx_ring *ring,
 200                                 int index, u8 owner)
 201 {
 202         struct mlx4_en_dev *mdev = priv->mdev;
 203         struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
 204         struct mlx4_en_tx_desc *tx_desc = ring->buf + index * TXBB_SIZE;
 205         struct mlx4_wqe_data_seg *data = (void *) tx_desc + tx_info->data_offset;
 206         struct sk_buff *skb = tx_info->skb;
 207         struct skb_frag_struct *frag;
 208         void *end = ring->buf + ring->buf_size;
 209         int frags = skb_shinfo(skb)->nr_frags;
 210         int i;
 211         __be32 *ptr = (__be32 *)tx_desc;
 212         __be32 stamp = cpu_to_be32(STAMP_VAL | (!!owner << STAMP_SHIFT));
 213
 214         /* Optimize the common case when there are no wraparounds */
 215         if (likely((void *) tx_desc + tx_info->nr_txbb * TXBB_SIZE <= end)) {
 216                 if (!tx_info->inl) {
 217                         if (tx_info->linear) {
 218                                 pci_unmap_single(mdev->pdev,
 219                                         (dma_addr_t) be64_to_cpu(data->addr),
 220                                          be32_to_cpu(data->byte_count),
 221                                          PCI_DMA_TODEVICE);
 222                                 ++data;
 223                         }
 224
 225                         for (i = 0; i < frags; i++) {
 226                                 frag = &skb_shinfo(skb)->frags[i];
 227                                 pci_unmap_page(mdev->pdev,
 228                                         (dma_addr_t) be64_to_cpu(data[i].addr),
 229                                         frag->size, PCI_DMA_TODEVICE);
 230                         }
 231                 }
 232                 /* Stamp the freed descriptor */
 233                 for (i = 0; i < tx_info->nr_txbb * TXBB_SIZE; i += STAMP_STRIDE) {
 234                         *ptr = stamp;
 235                         ptr += STAMP_DWORDS;
 236                 }
 237
 238         } else {
 239                 if (!tx_info->inl) {
 240                         if ((void *) data >= end) {
 241                                 data = (struct mlx4_wqe_data_seg *)
 242                                                 (ring->buf + ((void *) data - end));
 243                         }
 244
 245                         if (tx_info->linear) {
 246                                 pci_unmap_single(mdev->pdev,
 247                                         (dma_addr_t) be64_to_cpu(data->addr),
 248                                          be32_to_cpu(data->byte_count),
 249                                          PCI_DMA_TODEVICE);
 250                                 ++data;
 251                         }
 252
 253                         for (i = 0; i < frags; i++) {
 254                                 /* Check for wraparound before unmapping */
 255                                 if ((void *) data >= end)
 256                                         data = (struct mlx4_wqe_data_seg *) ring->buf;
 257                                 frag = &skb_shinfo(skb)->frags[i];
 258                                 pci_unmap_page(mdev->pdev,
 259                                         (dma_addr_t) be64_to_cpu(data->addr),
 260                                          frag->size, PCI_DMA_TODEVICE);
 261                                 ++data;
 262                         }
 263                 }
 264                 /* Stamp the freed descriptor */
 265                 for (i = 0; i < tx_info->nr_txbb * TXBB_SIZE; i += STAMP_STRIDE) {
 266                         *ptr = stamp;
 267                         ptr += STAMP_DWORDS;
 268                         if ((void *) ptr >= end) {
 269                                 ptr = ring->buf;
 270                                 stamp ^= cpu_to_be32(0x80000000);
 271                         }
 272                 }
 273
 274         }
 275         dev_kfree_skb_any(skb);
 276         return tx_info->nr_txbb;
 277 }
 278
 279
 280 int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring)
 281 {
 282         struct mlx4_en_priv *priv = netdev_priv(dev);
 283         int cnt = 0;
 284
 285         /* Skip last polled descriptor */
 286         ring->cons += ring->last_nr_txbb;
 287         en_dbg(DRV, priv, "Freeing Tx buf - cons:0x%x prod:0x%x\n",
 288                  ring->cons, ring->prod);
 289
 290         if ((u32) (ring->prod - ring->cons) > ring->size) {
 291                 if (netif_msg_tx_err(priv))
 292                         en_warn(priv, "Tx consumer passed producer!\n");
 293                 return 0;
 294         }
 295
 296         while (ring->cons != ring->prod) {
 297                 ring->last_nr_txbb = mlx4_en_free_tx_desc(priv, ring,
 298                                                 ring->cons & ring->size_mask,
 299                                                 !!(ring->cons & ring->size));
 300                 ring->cons += ring->last_nr_txbb;
 301                 cnt++;
 302         }
 303
 304         if (cnt)
 305                 en_dbg(DRV, priv, "Freed %d uncompleted tx descriptors\n", cnt);
 306
 307         return cnt;
 308 }
 309
 310
 311 static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
 312 {
 313         struct mlx4_en_priv *priv = netdev_priv(dev);
 314         struct mlx4_cq *mcq = &cq->mcq;
 315         struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
 316         struct mlx4_cqe *cqe = cq->buf;
 317         u16 index;
 318         u16 new_index;
 319         u32 txbbs_skipped = 0;
 320         u32 cq_last_sav;
 321
 322         /* index always points to the first TXBB of the last polled descriptor */
 323         index = ring->cons & ring->size_mask;
 324         new_index = be16_to_cpu(cqe->wqe_index) & ring->size_mask;
 325         if (index == new_index)
 326                 return;
 327
 328         if (!priv->port_up)
 329                 return;
 330
 331         /*
 332          * We use a two-stage loop:
 333          * - the first samples the HW-updated CQE
 334          * - the second frees TXBBs until the last sample
 335          * This lets us amortize CQE cache misses, while still polling the CQ
 336          * until is quiescent.
 337          */
 338         cq_last_sav = mcq->cons_index;
 339         do {
 340                 do {
 341                         /* Skip over last polled CQE */
 342                         index = (index + ring->last_nr_txbb) & ring->size_mask;
 343                         txbbs_skipped += ring->last_nr_txbb;
 344
 345                         /* Poll next CQE */
 346                         ring->last_nr_txbb = mlx4_en_free_tx_desc(
 347                                                 priv, ring, index,
 348                                                 !!((ring->cons + txbbs_skipped) &
 349                                                    ring->size));
 350                         ++mcq->cons_index;
 351
 352                 } while (index != new_index);
 353
 354                 new_index = be16_to_cpu(cqe->wqe_index) & ring->size_mask;
 355         } while (index != new_index);
 356         AVG_PERF_COUNTER(priv->pstats.tx_coal_avg,
 357                          (u32) (mcq->cons_index - cq_last_sav));
 358
 359         /*
 360          * To prevent CQ overflow we first update CQ consumer and only then
 361          * the ring consumer.
 362          */
 363         mlx4_cq_set_ci(mcq);
 364         wmb();
 365         ring->cons += txbbs_skipped;
 366
 367         /* Wakeup Tx queue if this ring stopped it */
 368         if (unlikely(ring->blocked)) {
 369                 if ((u32) (ring->prod - ring->cons) <=
 370                      ring->size - HEADROOM - MAX_DESC_TXBBS) {
 371                         ring->blocked = 0;
 372                         netif_tx_wake_queue(netdev_get_tx_queue(dev, cq->ring));
 373                         priv->port_stats.wake_queue++;
 374                 }
 375         }
 376 }
 377
 378 void mlx4_en_tx_irq(struct mlx4_cq *mcq)
 379 {
 380         struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
 381         struct mlx4_en_priv *priv = netdev_priv(cq->dev);
 382         struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
 383
 384         if (!spin_trylock(&ring->comp_lock))
 385                 return;
 386         mlx4_en_process_tx_cq(cq->dev, cq);
 387         mod_timer(&cq->timer, jiffies + 1);
 388         spin_unlock(&ring->comp_lock);
 389 }
 390
 391
 392 void mlx4_en_poll_tx_cq(unsigned long data)
 393 {
 394         struct mlx4_en_cq *cq = (struct mlx4_en_cq *) data;
 395         struct mlx4_en_priv *priv = netdev_priv(cq->dev);
 396         struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring];
 397         u32 inflight;
 398
 399         INC_PERF_COUNTER(priv->pstats.tx_poll);
 400
 401         if (!spin_trylock_irq(&ring->comp_lock)) {
 402                 mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
 403                 return;
 404         }
 405         mlx4_en_process_tx_cq(cq->dev, cq);
 406         inflight = (u32) (ring->prod - ring->cons - ring->last_nr_txbb);
 407
 408         /* If there are still packets in flight and the timer has not already
 409          * been scheduled by the Tx routine then schedule it here to guarantee
 410          * completion processing of these packets */
 411         if (inflight && priv->port_up)
 412                 mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
 413
 414         spin_unlock_irq(&ring->comp_lock);
 415 }
 416
 417 static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
 418                                                       struct mlx4_en_tx_ring *ring,
 419                                                       u32 index,
 420                                                       unsigned int desc_size)
 421 {
 422         u32 copy = (ring->size - index) * TXBB_SIZE;
 423         int i;
 424
 425         for (i = desc_size - copy - 4; i >= 0; i -= 4) {
 426                 if ((i & (TXBB_SIZE - 1)) == 0)
 427                         wmb();
 428
 429                 *((u32 *) (ring->buf + i)) =
 430                         *((u32 *) (ring->bounce_buf + copy + i));
 431         }
 432
 433         for (i = copy - 4; i >= 4 ; i -= 4) {
 434                 if ((i & (TXBB_SIZE - 1)) == 0)
 435                         wmb();
 436
 437                 *((u32 *) (ring->buf + index * TXBB_SIZE + i)) =
 438                         *((u32 *) (ring->bounce_buf + i));
 439         }
 440
 441         /* Return real descriptor location */
 442         return ring->buf + index * TXBB_SIZE;
 443 }
 444
 445 static inline void mlx4_en_xmit_poll(struct mlx4_en_priv *priv, int tx_ind)
 446 {
 447         struct mlx4_en_cq *cq = &priv->tx_cq[tx_ind];
 448         struct mlx4_en_tx_ring *ring = &priv->tx_ring[tx_ind];
 449         unsigned long flags;
 450
 451         /* If we don't have a pending timer, set one up to catch our recent
 452            post in case the interface becomes idle */
 453         if (!timer_pending(&cq->timer))
 454                 mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
 455
 456         /* Poll the CQ every mlx4_en_TX_MODER_POLL packets */
 457         if ((++ring->poll_cnt & (MLX4_EN_TX_POLL_MODER - 1)) == 0)
 458                 if (spin_trylock_irqsave(&ring->comp_lock, flags)) {
 459                         mlx4_en_process_tx_cq(priv->dev, cq);
 460                         spin_unlock_irqrestore(&ring->comp_lock, flags);
 461                 }
 462 }
 463
 464 static void *get_frag_ptr(struct sk_buff *skb)
 465 {
 466         struct skb_frag_struct *frag =  &skb_shinfo(skb)->frags[0];
 467         struct page *page = frag->page;
 468         void *ptr;
 469
 470         ptr = page_address(page);
 471         if (unlikely(!ptr))
 472                 return NULL;
 473
 474         return ptr + frag->page_offset;
 475 }
 476
 477 static int is_inline(struct sk_buff *skb, void **pfrag)
 478 {
 479         void *ptr;
 480
 481         if (inline_thold && !skb_is_gso(skb) && skb->len <= inline_thold) {
 482                 if (skb_shinfo(skb)->nr_frags == 1) {
 483                         ptr = get_frag_ptr(skb);
 484                         if (unlikely(!ptr))
 485                                 return 0;
 486
 487                         if (pfrag)
 488                                 *pfrag = ptr;
 489
 490                         return 1;
 491                 } else if (unlikely(skb_shinfo(skb)->nr_frags))
 492                         return 0;
 493                 else
 494                         return 1;
 495         }
 496
 497         return 0;
 498 }
 499
 500 static int inline_size(struct sk_buff *skb)
 501 {
 502         if (skb->len + CTRL_SIZE + sizeof(struct mlx4_wqe_inline_seg)
 503             <= MLX4_INLINE_ALIGN)
 504                 return ALIGN(skb->len + CTRL_SIZE +
 505                              sizeof(struct mlx4_wqe_inline_seg), 16);
 506         else
 507                 return ALIGN(skb->len + CTRL_SIZE + 2 *
 508                              sizeof(struct mlx4_wqe_inline_seg), 16);
 509 }
 510
 511 static int get_real_size(struct sk_buff *skb, struct net_device *dev,
 512                          int *lso_header_size)
 513 {
 514         struct mlx4_en_priv *priv = netdev_priv(dev);
 515         int real_size;
 516
 517         if (skb_is_gso(skb)) {
 518                 *lso_header_size = skb_transport_offset(skb) + tcp_hdrlen(skb);
 519                 real_size = CTRL_SIZE + skb_shinfo(skb)->nr_frags * DS_SIZE +
 520                         ALIGN(*lso_header_size + 4, DS_SIZE);
 521                 if (unlikely(*lso_header_size != skb_headlen(skb))) {
 522                         /* We add a segment for the skb linear buffer only if
 523                          * it contains data */
 524                         if (*lso_header_size < skb_headlen(skb))
 525                                 real_size += DS_SIZE;
 526                         else {
 527                                 if (netif_msg_tx_err(priv))
 528                                         en_warn(priv, "Non-linear headers\n");
 529                                 return 0;
 530                         }
 531                 }
 532         } else {
 533                 *lso_header_size = 0;
 534                 if (!is_inline(skb, NULL))
 535                         real_size = CTRL_SIZE + (skb_shinfo(skb)->nr_frags + 1) * DS_SIZE;
 536                 else
 537                         real_size = inline_size(skb);
 538         }
 539
 540         return real_size;
 541 }
 542
 543 static void build_inline_wqe(struct mlx4_en_tx_desc *tx_desc, struct sk_buff *skb,
 544                              int real_size, u16 *vlan_tag, int tx_ind, void *fragptr)
 545 {
 546         struct mlx4_wqe_inline_seg *inl = &tx_desc->inl;
 547         int spc = MLX4_INLINE_ALIGN - CTRL_SIZE - sizeof *inl;
 548
 549         if (skb->len <= spc) {
 550                 inl->byte_count = cpu_to_be32(1 << 31 | skb->len);
 551                 skb_copy_from_linear_data(skb, inl + 1, skb_headlen(skb));
 552                 if (skb_shinfo(skb)->nr_frags)
 553                         memcpy(((void *)(inl + 1)) + skb_headlen(skb), fragptr,
 554                                skb_shinfo(skb)->frags[0].size);
 555
 556         } else {
 557                 inl->byte_count = cpu_to_be32(1 << 31 | spc);
 558                 if (skb_headlen(skb) <= spc) {
 559                         skb_copy_from_linear_data(skb, inl + 1, skb_headlen(skb));
 560                         if (skb_headlen(skb) < spc) {
 561                                 memcpy(((void *)(inl + 1)) + skb_headlen(skb),
 562                                         fragptr, spc - skb_headlen(skb));
 563                                 fragptr +=  spc - skb_headlen(skb);
 564                         }
 565                         inl = (void *) (inl + 1) + spc;
 566                         memcpy(((void *)(inl + 1)), fragptr, skb->len - spc);
 567                 } else {
 568                         skb_copy_from_linear_data(skb, inl + 1, spc);
 569                         inl = (void *) (inl + 1) + spc;
 570                         skb_copy_from_linear_data_offset(skb, spc, inl + 1,
 571                                         skb_headlen(skb) - spc);
 572                         if (skb_shinfo(skb)->nr_frags)
 573                                 memcpy(((void *)(inl + 1)) + skb_headlen(skb) - spc,
 574                                         fragptr, skb_shinfo(skb)->frags[0].size);
 575                 }
 576
 577                 wmb();
 578                 inl->byte_count = cpu_to_be32(1 << 31 | (skb->len - spc));
 579         }
 580         tx_desc->ctrl.vlan_tag = cpu_to_be16(*vlan_tag);
 581         tx_desc->ctrl.ins_vlan = MLX4_WQE_CTRL_INS_VLAN * !!(*vlan_tag);
 582         tx_desc->ctrl.fence_size = (real_size / 16) & 0x3f;
 583 }
 584
 585 u16 mlx4_en_select_queue(struct net_device *dev, struct sk_buff *skb)
 586 {
 587         struct mlx4_en_priv *priv = netdev_priv(dev);
 588         u16 vlan_tag = 0;
 589
 590         /* If we support per priority flow control and the packet contains
 591          * a vlan tag, send the packet to the TX ring assigned to that priority
 592          */
 593         if (priv->prof->rx_ppp && vlan_tx_tag_present(skb)) {
 594                 vlan_tag = vlan_tx_tag_get(skb);
 595                 return MLX4_EN_NUM_TX_RINGS + (vlan_tag >> 13);
 596         }
 597
 598         return skb_tx_hash(dev, skb);
 599 }
 600
 601 static void mlx4_bf_copy(unsigned long *dst, unsigned long *src, unsigned bytecnt)
 602 {
 603         __iowrite64_copy(dst, src, bytecnt / 8);
 604 }
 605
 606 netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 607 {
 608         struct mlx4_en_priv *priv = netdev_priv(dev);
 609         struct mlx4_en_dev *mdev = priv->mdev;
 610         struct mlx4_en_tx_ring *ring;
 611         struct mlx4_en_cq *cq;
 612         struct mlx4_en_tx_desc *tx_desc;
 613         struct mlx4_wqe_data_seg *data;
 614         struct skb_frag_struct *frag;
 615         struct mlx4_en_tx_info *tx_info;
 616         struct ethhdr *ethh;
 617         u64 mac;
 618         u32 mac_l, mac_h;
 619         int tx_ind = 0;
 620         int nr_txbb;
 621         int desc_size;
 622         int real_size;
 623         dma_addr_t dma;
 624         u32 index, bf_index;
 625         __be32 op_own;
 626         u16 vlan_tag = 0;
 627         int i;
 628         int lso_header_size;
 629         void *fragptr;
 630         bool bounce = false;
 631
 632         if (!priv->port_up)
 633                 goto tx_drop;
 634
 635         real_size = get_real_size(skb, dev, &lso_header_size);
 636         if (unlikely(!real_size))
 637                 goto tx_drop;
 638
 639         /* Align descriptor to TXBB size */
 640         desc_size = ALIGN(real_size, TXBB_SIZE);
 641         nr_txbb = desc_size / TXBB_SIZE;
 642         if (unlikely(nr_txbb > MAX_DESC_TXBBS)) {
 643                 if (netif_msg_tx_err(priv))
 644                         en_warn(priv, "Oversized header or SG list\n");
 645                 goto tx_drop;
 646         }
 647
 648         tx_ind = skb->queue_mapping;
 649         ring = &priv->tx_ring[tx_ind];
 650         if (vlan_tx_tag_present(skb))
 651                 vlan_tag = vlan_tx_tag_get(skb);
 652
 653         /* Check available TXBBs And 2K spare for prefetch */
 654         if (unlikely(((int)(ring->prod - ring->cons)) >
 655                      ring->size - HEADROOM - MAX_DESC_TXBBS)) {
 656                 /* every full Tx ring stops queue */
 657                 netif_tx_stop_queue(netdev_get_tx_queue(dev, tx_ind));
 658                 ring->blocked = 1;
 659                 priv->port_stats.queue_stopped++;
 660
 661                 /* Use interrupts to find out when queue opened */
 662                 cq = &priv->tx_cq[tx_ind];
 663                 mlx4_en_arm_cq(priv, cq);
 664                 return NETDEV_TX_BUSY;
 665         }
 666
 667         /* Track current inflight packets for performance analysis */
 668         AVG_PERF_COUNTER(priv->pstats.inflight_avg,
 669                          (u32) (ring->prod - ring->cons - 1));
 670
 671         /* Packet is good - grab an index and transmit it */
 672         index = ring->prod & ring->size_mask;
 673         bf_index = ring->prod;
 674
 675         /* See if we have enough space for whole descriptor TXBB for setting
 676          * SW ownership on next descriptor; if not, use a bounce buffer. */
 677         if (likely(index + nr_txbb <= ring->size))
 678                 tx_desc = ring->buf + index * TXBB_SIZE;
 679         else {
 680                 tx_desc = (struct mlx4_en_tx_desc *) ring->bounce_buf;
 681                 bounce = true;
 682         }
 683
 684         /* Save skb in tx_info ring */
 685         tx_info = &ring->tx_info[index];
 686         tx_info->skb = skb;
 687         tx_info->nr_txbb = nr_txbb;
 688
 689         /* Prepare ctrl segement apart opcode+ownership, which depends on
 690          * whether LSO is used */
 691         tx_desc->ctrl.vlan_tag = cpu_to_be16(vlan_tag);
 692         tx_desc->ctrl.ins_vlan = MLX4_WQE_CTRL_INS_VLAN * !!vlan_tag;
 693         tx_desc->ctrl.fence_size = (real_size / 16) & 0x3f;
 694         tx_desc->ctrl.srcrb_flags = cpu_to_be32(MLX4_WQE_CTRL_CQ_UPDATE |
 695                                                 MLX4_WQE_CTRL_SOLICITED);
 696         if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
 697                 tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM |
 698                                                          MLX4_WQE_CTRL_TCP_UDP_CSUM);
 699                 priv->port_stats.tx_chksum_offload++;
 700         }
 701
 702         if (unlikely(priv->validate_loopback)) {
 703                 /* Copy dst mac address to wqe */
 704                 skb_reset_mac_header(skb);
 705                 ethh = eth_hdr(skb);
 706                 if (ethh && ethh->h_dest) {
 707                         mac = mlx4_en_mac_to_u64(ethh->h_dest);
 708                         mac_h = (u32) ((mac & 0xffff00000000ULL) >> 16);
 709                         mac_l = (u32) (mac & 0xffffffff);
 710                         tx_desc->ctrl.srcrb_flags |= cpu_to_be32(mac_h);
 711                         tx_desc->ctrl.imm = cpu_to_be32(mac_l);
 712                 }
 713         }
 714
 715         /* Handle LSO (TSO) packets */
 716         if (lso_header_size) {
 717                 /* Mark opcode as LSO */
 718                 op_own = cpu_to_be32(MLX4_OPCODE_LSO | (1 << 6)) |
 719                         ((ring->prod & ring->size) ?
 720                                 cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
 721
 722                 /* Fill in the LSO prefix */
 723                 tx_desc->lso.mss_hdr_size = cpu_to_be32(
 724                         skb_shinfo(skb)->gso_size << 16 | lso_header_size);
 725
 726                 /* Copy headers;
 727                  * note that we already verified that it is linear */
 728                 memcpy(tx_desc->lso.header, skb->data, lso_header_size);
 729                 data = ((void *) &tx_desc->lso +
 730                         ALIGN(lso_header_size + 4, DS_SIZE));
 731
 732                 priv->port_stats.tso_packets++;
 733                 i = ((skb->len - lso_header_size) / skb_shinfo(skb)->gso_size) +
 734                         !!((skb->len - lso_header_size) % skb_shinfo(skb)->gso_size);
 735                 ring->bytes += skb->len + (i - 1) * lso_header_size;
 736                 ring->packets += i;
 737         } else {
 738                 /* Normal (Non LSO) packet */
 739                 op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
 740                         ((ring->prod & ring->size) ?
 741                          cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
 742                 data = &tx_desc->data;
 743                 ring->bytes += max(skb->len, (unsigned int) ETH_ZLEN);
 744                 ring->packets++;
 745
 746         }
 747         AVG_PERF_COUNTER(priv->pstats.tx_pktsz_avg, skb->len);
 748
 749
 750         /* valid only for none inline segments */
 751         tx_info->data_offset = (void *) data - (void *) tx_desc;
 752
 753         tx_info->linear = (lso_header_size < skb_headlen(skb) && !is_inline(skb, NULL)) ? 1 : 0;
 754         data += skb_shinfo(skb)->nr_frags + tx_info->linear - 1;
 755
 756         if (!is_inline(skb, &fragptr)) {
 757                 /* Map fragments */
 758                 for (i = skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) {
 759                         frag = &skb_shinfo(skb)->frags[i];
 760                         dma = pci_map_page(mdev->dev->pdev, frag->page, frag->page_offset,
 761                                            frag->size, PCI_DMA_TODEVICE);
 762                         data->addr = cpu_to_be64(dma);
 763                         data->lkey = cpu_to_be32(mdev->mr.key);
 764                         wmb();
 765                         data->byte_count = cpu_to_be32(frag->size);
 766                         --data;
 767                 }
 768
 769                 /* Map linear part */
 770                 if (tx_info->linear) {
 771                         dma = pci_map_single(mdev->dev->pdev, skb->data + lso_header_size,
 772                                              skb_headlen(skb) - lso_header_size, PCI_DMA_TODEVICE);
 773                         data->addr = cpu_to_be64(dma);
 774                         data->lkey = cpu_to_be32(mdev->mr.key);
 775                         wmb();
 776                         data->byte_count = cpu_to_be32(skb_headlen(skb) - lso_header_size);
 777                 }
 778                 tx_info->inl = 0;
 779         } else {
 780                 build_inline_wqe(tx_desc, skb, real_size, &vlan_tag, tx_ind, fragptr);
 781                 tx_info->inl = 1;
 782         }
 783
 784         ring->prod += nr_txbb;
 785
 786         /* If we used a bounce buffer then copy descriptor back into place */
 787         if (bounce)
 788                 tx_desc = mlx4_en_bounce_to_desc(priv, ring, index, desc_size);
 789
 790         /* Run destructor before passing skb to HW */
 791         if (likely(!skb_shared(skb)))
 792                 skb_orphan(skb);
 793
 794         if (ring->bf_enabled && desc_size <= MAX_BF && !bounce && !vlan_tag) {
 795                 *(u32 *) (&tx_desc->ctrl.vlan_tag) |= ring->doorbell_qpn;
 796                 op_own |= htonl((bf_index & 0xffff) << 8);
 797                 /* Ensure new descirptor hits memory
 798                 * before setting ownership of this descriptor to HW */
 799                 wmb();
 800                 tx_desc->ctrl.owner_opcode = op_own;
 801
 802                 wmb();
 803
 804                 mlx4_bf_copy(ring->bf.reg + ring->bf.offset, (unsigned long *) &tx_desc->ctrl,
 805                      desc_size);
 806
 807                 wmb();
 808
 809                 ring->bf.offset ^= ring->bf.buf_size;
 810         } else {
 811                 /* Ensure new descirptor hits memory
 812                 * before setting ownership of this descriptor to HW */
 813                 wmb();
 814                 tx_desc->ctrl.owner_opcode = op_own;
 815                 wmb();
 816                 writel(ring->doorbell_qpn, ring->bf.uar->map + MLX4_SEND_DOORBELL);
 817         }
 818
 819         /* Poll CQ here */
 820         mlx4_en_xmit_poll(priv, tx_ind);
 821
 822         return NETDEV_TX_OK;
 823
 824 tx_drop:
 825         dev_kfree_skb_any(skb);
 826         priv->stats.tx_dropped++;
 827         return NETDEV_TX_OK;
 828 }
 829