GNU Linux-libre 4.14.266-gnu1
[releases.git] / drivers / net / ethernet / mellanox / 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/prefetch.h>
41 #include <linux/vmalloc.h>
42 #include <linux/tcp.h>
43 #include <linux/ip.h>
44 #include <linux/ipv6.h>
45 #include <linux/moduleparam.h>
46
47 #include "mlx4_en.h"
48
49 int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv,
50                            struct mlx4_en_tx_ring **pring, u32 size,
51                            u16 stride, int node, int queue_index)
52 {
53         struct mlx4_en_dev *mdev = priv->mdev;
54         struct mlx4_en_tx_ring *ring;
55         int tmp;
56         int err;
57
58         ring = kzalloc_node(sizeof(*ring), GFP_KERNEL, node);
59         if (!ring) {
60                 ring = kzalloc(sizeof(*ring), GFP_KERNEL);
61                 if (!ring) {
62                         en_err(priv, "Failed allocating TX ring\n");
63                         return -ENOMEM;
64                 }
65         }
66
67         ring->size = size;
68         ring->size_mask = size - 1;
69         ring->sp_stride = stride;
70         ring->full_size = ring->size - HEADROOM - MAX_DESC_TXBBS;
71
72         tmp = size * sizeof(struct mlx4_en_tx_info);
73         ring->tx_info = kvmalloc_node(tmp, GFP_KERNEL, node);
74         if (!ring->tx_info) {
75                 err = -ENOMEM;
76                 goto err_ring;
77         }
78
79         en_dbg(DRV, priv, "Allocated tx_info ring at addr:%p size:%d\n",
80                  ring->tx_info, tmp);
81
82         ring->bounce_buf = kmalloc_node(MAX_DESC_SIZE, GFP_KERNEL, node);
83         if (!ring->bounce_buf) {
84                 ring->bounce_buf = kmalloc(MAX_DESC_SIZE, GFP_KERNEL);
85                 if (!ring->bounce_buf) {
86                         err = -ENOMEM;
87                         goto err_info;
88                 }
89         }
90         ring->buf_size = ALIGN(size * ring->sp_stride, MLX4_EN_PAGE_SIZE);
91
92         /* Allocate HW buffers on provided NUMA node */
93         set_dev_node(&mdev->dev->persist->pdev->dev, node);
94         err = mlx4_alloc_hwq_res(mdev->dev, &ring->sp_wqres, ring->buf_size);
95         set_dev_node(&mdev->dev->persist->pdev->dev, mdev->dev->numa_node);
96         if (err) {
97                 en_err(priv, "Failed allocating hwq resources\n");
98                 goto err_bounce;
99         }
100
101         ring->buf = ring->sp_wqres.buf.direct.buf;
102
103         en_dbg(DRV, priv, "Allocated TX ring (addr:%p) - buf:%p size:%d buf_size:%d dma:%llx\n",
104                ring, ring->buf, ring->size, ring->buf_size,
105                (unsigned long long) ring->sp_wqres.buf.direct.map);
106
107         err = mlx4_qp_reserve_range(mdev->dev, 1, 1, &ring->qpn,
108                                     MLX4_RESERVE_ETH_BF_QP,
109                                     MLX4_RES_USAGE_DRIVER);
110         if (err) {
111                 en_err(priv, "failed reserving qp for TX ring\n");
112                 goto err_hwq_res;
113         }
114
115         err = mlx4_qp_alloc(mdev->dev, ring->qpn, &ring->sp_qp);
116         if (err) {
117                 en_err(priv, "Failed allocating qp %d\n", ring->qpn);
118                 goto err_reserve;
119         }
120         ring->sp_qp.event = mlx4_en_sqp_event;
121
122         err = mlx4_bf_alloc(mdev->dev, &ring->bf, node);
123         if (err) {
124                 en_dbg(DRV, priv, "working without blueflame (%d)\n", err);
125                 ring->bf.uar = &mdev->priv_uar;
126                 ring->bf.uar->map = mdev->uar_map;
127                 ring->bf_enabled = false;
128                 ring->bf_alloced = false;
129                 priv->pflags &= ~MLX4_EN_PRIV_FLAGS_BLUEFLAME;
130         } else {
131                 ring->bf_alloced = true;
132                 ring->bf_enabled = !!(priv->pflags &
133                                       MLX4_EN_PRIV_FLAGS_BLUEFLAME);
134         }
135
136         ring->hwtstamp_tx_type = priv->hwtstamp_config.tx_type;
137         ring->queue_index = queue_index;
138
139         if (queue_index < priv->num_tx_rings_p_up)
140                 cpumask_set_cpu(cpumask_local_spread(queue_index,
141                                                      priv->mdev->dev->numa_node),
142                                 &ring->sp_affinity_mask);
143
144         *pring = ring;
145         return 0;
146
147 err_reserve:
148         mlx4_qp_release_range(mdev->dev, ring->qpn, 1);
149 err_hwq_res:
150         mlx4_free_hwq_res(mdev->dev, &ring->sp_wqres, ring->buf_size);
151 err_bounce:
152         kfree(ring->bounce_buf);
153         ring->bounce_buf = NULL;
154 err_info:
155         kvfree(ring->tx_info);
156         ring->tx_info = NULL;
157 err_ring:
158         kfree(ring);
159         *pring = NULL;
160         return err;
161 }
162
163 void mlx4_en_destroy_tx_ring(struct mlx4_en_priv *priv,
164                              struct mlx4_en_tx_ring **pring)
165 {
166         struct mlx4_en_dev *mdev = priv->mdev;
167         struct mlx4_en_tx_ring *ring = *pring;
168         en_dbg(DRV, priv, "Destroying tx ring, qpn: %d\n", ring->qpn);
169
170         if (ring->bf_alloced)
171                 mlx4_bf_free(mdev->dev, &ring->bf);
172         mlx4_qp_remove(mdev->dev, &ring->sp_qp);
173         mlx4_qp_free(mdev->dev, &ring->sp_qp);
174         mlx4_qp_release_range(priv->mdev->dev, ring->qpn, 1);
175         mlx4_free_hwq_res(mdev->dev, &ring->sp_wqres, ring->buf_size);
176         kfree(ring->bounce_buf);
177         ring->bounce_buf = NULL;
178         kvfree(ring->tx_info);
179         ring->tx_info = NULL;
180         kfree(ring);
181         *pring = NULL;
182 }
183
184 int mlx4_en_activate_tx_ring(struct mlx4_en_priv *priv,
185                              struct mlx4_en_tx_ring *ring,
186                              int cq, int user_prio)
187 {
188         struct mlx4_en_dev *mdev = priv->mdev;
189         int err;
190
191         ring->sp_cqn = cq;
192         ring->prod = 0;
193         ring->cons = 0xffffffff;
194         ring->last_nr_txbb = 1;
195         memset(ring->tx_info, 0, ring->size * sizeof(struct mlx4_en_tx_info));
196         memset(ring->buf, 0, ring->buf_size);
197         ring->free_tx_desc = mlx4_en_free_tx_desc;
198
199         ring->sp_qp_state = MLX4_QP_STATE_RST;
200         ring->doorbell_qpn = cpu_to_be32(ring->sp_qp.qpn << 8);
201         ring->mr_key = cpu_to_be32(mdev->mr.key);
202
203         mlx4_en_fill_qp_context(priv, ring->size, ring->sp_stride, 1, 0, ring->qpn,
204                                 ring->sp_cqn, user_prio, &ring->sp_context);
205         if (ring->bf_alloced)
206                 ring->sp_context.usr_page =
207                         cpu_to_be32(mlx4_to_hw_uar_index(mdev->dev,
208                                                          ring->bf.uar->index));
209
210         err = mlx4_qp_to_ready(mdev->dev, &ring->sp_wqres.mtt, &ring->sp_context,
211                                &ring->sp_qp, &ring->sp_qp_state);
212         if (!cpumask_empty(&ring->sp_affinity_mask))
213                 netif_set_xps_queue(priv->dev, &ring->sp_affinity_mask,
214                                     ring->queue_index);
215
216         return err;
217 }
218
219 void mlx4_en_deactivate_tx_ring(struct mlx4_en_priv *priv,
220                                 struct mlx4_en_tx_ring *ring)
221 {
222         struct mlx4_en_dev *mdev = priv->mdev;
223
224         mlx4_qp_modify(mdev->dev, NULL, ring->sp_qp_state,
225                        MLX4_QP_STATE_RST, NULL, 0, 0, &ring->sp_qp);
226 }
227
228 static inline bool mlx4_en_is_tx_ring_full(struct mlx4_en_tx_ring *ring)
229 {
230         return ring->prod - ring->cons > ring->full_size;
231 }
232
233 static void mlx4_en_stamp_wqe(struct mlx4_en_priv *priv,
234                               struct mlx4_en_tx_ring *ring, int index,
235                               u8 owner)
236 {
237         __be32 stamp = cpu_to_be32(STAMP_VAL | (!!owner << STAMP_SHIFT));
238         struct mlx4_en_tx_desc *tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
239         struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
240         void *end = ring->buf + ring->buf_size;
241         __be32 *ptr = (__be32 *)tx_desc;
242         int i;
243
244         /* Optimize the common case when there are no wraparounds */
245         if (likely((void *)tx_desc +
246                    (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) {
247                 /* Stamp the freed descriptor */
248                 for (i = 0; i < tx_info->nr_txbb << LOG_TXBB_SIZE;
249                      i += STAMP_STRIDE) {
250                         *ptr = stamp;
251                         ptr += STAMP_DWORDS;
252                 }
253         } else {
254                 /* Stamp the freed descriptor */
255                 for (i = 0; i < tx_info->nr_txbb << LOG_TXBB_SIZE;
256                      i += STAMP_STRIDE) {
257                         *ptr = stamp;
258                         ptr += STAMP_DWORDS;
259                         if ((void *)ptr >= end) {
260                                 ptr = ring->buf;
261                                 stamp ^= cpu_to_be32(0x80000000);
262                         }
263                 }
264         }
265 }
266
267
268 u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
269                          struct mlx4_en_tx_ring *ring,
270                          int index, u64 timestamp,
271                          int napi_mode)
272 {
273         struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
274         struct mlx4_en_tx_desc *tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
275         struct mlx4_wqe_data_seg *data = (void *) tx_desc + tx_info->data_offset;
276         void *end = ring->buf + ring->buf_size;
277         struct sk_buff *skb = tx_info->skb;
278         int nr_maps = tx_info->nr_maps;
279         int i;
280
281         /* We do not touch skb here, so prefetch skb->users location
282          * to speedup consume_skb()
283          */
284         prefetchw(&skb->users);
285
286         if (unlikely(timestamp)) {
287                 struct skb_shared_hwtstamps hwts;
288
289                 mlx4_en_fill_hwtstamps(priv->mdev, &hwts, timestamp);
290                 skb_tstamp_tx(skb, &hwts);
291         }
292
293         if (!tx_info->inl) {
294                 if (tx_info->linear)
295                         dma_unmap_single(priv->ddev,
296                                          tx_info->map0_dma,
297                                          tx_info->map0_byte_count,
298                                          PCI_DMA_TODEVICE);
299                 else
300                         dma_unmap_page(priv->ddev,
301                                        tx_info->map0_dma,
302                                        tx_info->map0_byte_count,
303                                        PCI_DMA_TODEVICE);
304                 /* Optimize the common case when there are no wraparounds */
305                 if (likely((void *)tx_desc +
306                            (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) {
307                         for (i = 1; i < nr_maps; i++) {
308                                 data++;
309                                 dma_unmap_page(priv->ddev,
310                                         (dma_addr_t)be64_to_cpu(data->addr),
311                                         be32_to_cpu(data->byte_count),
312                                         PCI_DMA_TODEVICE);
313                         }
314                 } else {
315                         if ((void *)data >= end)
316                                 data = ring->buf + ((void *)data - end);
317
318                         for (i = 1; i < nr_maps; i++) {
319                                 data++;
320                                 /* Check for wraparound before unmapping */
321                                 if ((void *) data >= end)
322                                         data = ring->buf;
323                                 dma_unmap_page(priv->ddev,
324                                         (dma_addr_t)be64_to_cpu(data->addr),
325                                         be32_to_cpu(data->byte_count),
326                                         PCI_DMA_TODEVICE);
327                         }
328                 }
329         }
330         napi_consume_skb(skb, napi_mode);
331
332         return tx_info->nr_txbb;
333 }
334
335 u32 mlx4_en_recycle_tx_desc(struct mlx4_en_priv *priv,
336                             struct mlx4_en_tx_ring *ring,
337                             int index, u64 timestamp,
338                             int napi_mode)
339 {
340         struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
341         struct mlx4_en_rx_alloc frame = {
342                 .page = tx_info->page,
343                 .dma = tx_info->map0_dma,
344         };
345
346         if (!napi_mode || !mlx4_en_rx_recycle(ring->recycle_ring, &frame)) {
347                 dma_unmap_page(priv->ddev, tx_info->map0_dma,
348                                PAGE_SIZE, priv->dma_dir);
349                 put_page(tx_info->page);
350         }
351
352         return tx_info->nr_txbb;
353 }
354
355 int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring)
356 {
357         struct mlx4_en_priv *priv = netdev_priv(dev);
358         int cnt = 0;
359
360         /* Skip last polled descriptor */
361         ring->cons += ring->last_nr_txbb;
362         en_dbg(DRV, priv, "Freeing Tx buf - cons:0x%x prod:0x%x\n",
363                  ring->cons, ring->prod);
364
365         if ((u32) (ring->prod - ring->cons) > ring->size) {
366                 if (netif_msg_tx_err(priv))
367                         en_warn(priv, "Tx consumer passed producer!\n");
368                 return 0;
369         }
370
371         while (ring->cons != ring->prod) {
372                 ring->last_nr_txbb = ring->free_tx_desc(priv, ring,
373                                                 ring->cons & ring->size_mask,
374                                                 0, 0 /* Non-NAPI caller */);
375                 ring->cons += ring->last_nr_txbb;
376                 cnt++;
377         }
378
379         if (ring->tx_queue)
380                 netdev_tx_reset_queue(ring->tx_queue);
381
382         if (cnt)
383                 en_dbg(DRV, priv, "Freed %d uncompleted tx descriptors\n", cnt);
384
385         return cnt;
386 }
387
388 static void mlx4_en_handle_err_cqe(struct mlx4_en_priv *priv, struct mlx4_err_cqe *err_cqe,
389                                    u16 cqe_index, struct mlx4_en_tx_ring *ring)
390 {
391         struct mlx4_en_dev *mdev = priv->mdev;
392         struct mlx4_en_tx_info *tx_info;
393         struct mlx4_en_tx_desc *tx_desc;
394         u16 wqe_index;
395         int desc_size;
396
397         en_err(priv, "CQE error - cqn 0x%x, ci 0x%x, vendor syndrome: 0x%x syndrome: 0x%x\n",
398                ring->sp_cqn, cqe_index, err_cqe->vendor_err_syndrome, err_cqe->syndrome);
399         print_hex_dump(KERN_WARNING, "", DUMP_PREFIX_OFFSET, 16, 1, err_cqe, sizeof(*err_cqe),
400                        false);
401
402         wqe_index = be16_to_cpu(err_cqe->wqe_index) & ring->size_mask;
403         tx_info = &ring->tx_info[wqe_index];
404         desc_size = tx_info->nr_txbb << LOG_TXBB_SIZE;
405         en_err(priv, "Related WQE - qpn 0x%x, wqe index 0x%x, wqe size 0x%x\n", ring->qpn,
406                wqe_index, desc_size);
407         tx_desc = ring->buf + (wqe_index << LOG_TXBB_SIZE);
408         print_hex_dump(KERN_WARNING, "", DUMP_PREFIX_OFFSET, 16, 1, tx_desc, desc_size, false);
409
410         if (test_and_set_bit(MLX4_EN_STATE_FLAG_RESTARTING, &priv->state))
411                 return;
412
413         en_err(priv, "Scheduling port restart\n");
414         queue_work(mdev->workqueue, &priv->restart_task);
415 }
416
417 bool mlx4_en_process_tx_cq(struct net_device *dev,
418                            struct mlx4_en_cq *cq, int napi_budget)
419 {
420         struct mlx4_en_priv *priv = netdev_priv(dev);
421         struct mlx4_cq *mcq = &cq->mcq;
422         struct mlx4_en_tx_ring *ring = priv->tx_ring[cq->type][cq->ring];
423         struct mlx4_cqe *cqe;
424         u16 index, ring_index, stamp_index;
425         u32 txbbs_skipped = 0;
426         u32 txbbs_stamp = 0;
427         u32 cons_index = mcq->cons_index;
428         int size = cq->size;
429         u32 size_mask = ring->size_mask;
430         struct mlx4_cqe *buf = cq->buf;
431         u32 packets = 0;
432         u32 bytes = 0;
433         int factor = priv->cqe_factor;
434         int done = 0;
435         int budget = priv->tx_work_limit;
436         u32 last_nr_txbb;
437         u32 ring_cons;
438
439         if (unlikely(!priv->port_up))
440                 return true;
441
442         netdev_txq_bql_complete_prefetchw(ring->tx_queue);
443
444         index = cons_index & size_mask;
445         cqe = mlx4_en_get_cqe(buf, index, priv->cqe_size) + factor;
446         last_nr_txbb = ACCESS_ONCE(ring->last_nr_txbb);
447         ring_cons = ACCESS_ONCE(ring->cons);
448         ring_index = ring_cons & size_mask;
449         stamp_index = ring_index;
450
451         /* Process all completed CQEs */
452         while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
453                         cons_index & size) && (done < budget)) {
454                 u16 new_index;
455
456                 /*
457                  * make sure we read the CQE after we read the
458                  * ownership bit
459                  */
460                 dma_rmb();
461
462                 if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
463                              MLX4_CQE_OPCODE_ERROR))
464                         if (!test_and_set_bit(MLX4_EN_TX_RING_STATE_RECOVERING, &ring->state))
465                                 mlx4_en_handle_err_cqe(priv, (struct mlx4_err_cqe *)cqe, index,
466                                                        ring);
467
468                 /* Skip over last polled CQE */
469                 new_index = be16_to_cpu(cqe->wqe_index) & size_mask;
470
471                 do {
472                         u64 timestamp = 0;
473
474                         txbbs_skipped += last_nr_txbb;
475                         ring_index = (ring_index + last_nr_txbb) & size_mask;
476
477                         if (unlikely(ring->tx_info[ring_index].ts_requested))
478                                 timestamp = mlx4_en_get_cqe_ts(cqe);
479
480                         /* free next descriptor */
481                         last_nr_txbb = ring->free_tx_desc(
482                                         priv, ring, ring_index,
483                                         timestamp, napi_budget);
484
485                         mlx4_en_stamp_wqe(priv, ring, stamp_index,
486                                           !!((ring_cons + txbbs_stamp) &
487                                                 ring->size));
488                         stamp_index = ring_index;
489                         txbbs_stamp = txbbs_skipped;
490                         packets++;
491                         bytes += ring->tx_info[ring_index].nr_bytes;
492                 } while ((++done < budget) && (ring_index != new_index));
493
494                 ++cons_index;
495                 index = cons_index & size_mask;
496                 cqe = mlx4_en_get_cqe(buf, index, priv->cqe_size) + factor;
497         }
498
499         /*
500          * To prevent CQ overflow we first update CQ consumer and only then
501          * the ring consumer.
502          */
503         mcq->cons_index = cons_index;
504         mlx4_cq_set_ci(mcq);
505         wmb();
506
507         /* we want to dirty this cache line once */
508         ACCESS_ONCE(ring->last_nr_txbb) = last_nr_txbb;
509         ACCESS_ONCE(ring->cons) = ring_cons + txbbs_skipped;
510
511         if (cq->type == TX_XDP)
512                 return done < budget;
513
514         netdev_tx_completed_queue(ring->tx_queue, packets, bytes);
515
516         /* Wakeup Tx queue if this stopped, and ring is not full.
517          */
518         if (netif_tx_queue_stopped(ring->tx_queue) &&
519             !mlx4_en_is_tx_ring_full(ring)) {
520                 netif_tx_wake_queue(ring->tx_queue);
521                 ring->wake_queue++;
522         }
523
524         return done < budget;
525 }
526
527 void mlx4_en_tx_irq(struct mlx4_cq *mcq)
528 {
529         struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
530         struct mlx4_en_priv *priv = netdev_priv(cq->dev);
531
532         if (likely(priv->port_up))
533                 napi_schedule_irqoff(&cq->napi);
534         else
535                 mlx4_en_arm_cq(priv, cq);
536 }
537
538 /* TX CQ polling - called by NAPI */
539 int mlx4_en_poll_tx_cq(struct napi_struct *napi, int budget)
540 {
541         struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
542         struct net_device *dev = cq->dev;
543         struct mlx4_en_priv *priv = netdev_priv(dev);
544         bool clean_complete;
545
546         clean_complete = mlx4_en_process_tx_cq(dev, cq, budget);
547         if (!clean_complete)
548                 return budget;
549
550         napi_complete(napi);
551         mlx4_en_arm_cq(priv, cq);
552
553         return 0;
554 }
555
556 static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
557                                                       struct mlx4_en_tx_ring *ring,
558                                                       u32 index,
559                                                       unsigned int desc_size)
560 {
561         u32 copy = (ring->size - index) << LOG_TXBB_SIZE;
562         int i;
563
564         for (i = desc_size - copy - 4; i >= 0; i -= 4) {
565                 if ((i & (TXBB_SIZE - 1)) == 0)
566                         wmb();
567
568                 *((u32 *) (ring->buf + i)) =
569                         *((u32 *) (ring->bounce_buf + copy + i));
570         }
571
572         for (i = copy - 4; i >= 4 ; i -= 4) {
573                 if ((i & (TXBB_SIZE - 1)) == 0)
574                         wmb();
575
576                 *((u32 *)(ring->buf + (index << LOG_TXBB_SIZE) + i)) =
577                         *((u32 *) (ring->bounce_buf + i));
578         }
579
580         /* Return real descriptor location */
581         return ring->buf + (index << LOG_TXBB_SIZE);
582 }
583
584 /* Decide if skb can be inlined in tx descriptor to avoid dma mapping
585  *
586  * It seems strange we do not simply use skb_copy_bits().
587  * This would allow to inline all skbs iff skb->len <= inline_thold
588  *
589  * Note that caller already checked skb was not a gso packet
590  */
591 static bool is_inline(int inline_thold, const struct sk_buff *skb,
592                       const struct skb_shared_info *shinfo,
593                       void **pfrag)
594 {
595         void *ptr;
596
597         if (skb->len > inline_thold || !inline_thold)
598                 return false;
599
600         if (shinfo->nr_frags == 1) {
601                 ptr = skb_frag_address_safe(&shinfo->frags[0]);
602                 if (unlikely(!ptr))
603                         return false;
604                 *pfrag = ptr;
605                 return true;
606         }
607         if (shinfo->nr_frags)
608                 return false;
609         return true;
610 }
611
612 static int inline_size(const struct sk_buff *skb)
613 {
614         if (skb->len + CTRL_SIZE + sizeof(struct mlx4_wqe_inline_seg)
615             <= MLX4_INLINE_ALIGN)
616                 return ALIGN(skb->len + CTRL_SIZE +
617                              sizeof(struct mlx4_wqe_inline_seg), 16);
618         else
619                 return ALIGN(skb->len + CTRL_SIZE + 2 *
620                              sizeof(struct mlx4_wqe_inline_seg), 16);
621 }
622
623 static int get_real_size(const struct sk_buff *skb,
624                          const struct skb_shared_info *shinfo,
625                          struct net_device *dev,
626                          int *lso_header_size,
627                          bool *inline_ok,
628                          void **pfrag)
629 {
630         struct mlx4_en_priv *priv = netdev_priv(dev);
631         int real_size;
632
633         if (shinfo->gso_size) {
634                 *inline_ok = false;
635                 if (skb->encapsulation)
636                         *lso_header_size = (skb_inner_transport_header(skb) - skb->data) + inner_tcp_hdrlen(skb);
637                 else
638                         *lso_header_size = skb_transport_offset(skb) + tcp_hdrlen(skb);
639                 real_size = CTRL_SIZE + shinfo->nr_frags * DS_SIZE +
640                         ALIGN(*lso_header_size + 4, DS_SIZE);
641                 if (unlikely(*lso_header_size != skb_headlen(skb))) {
642                         /* We add a segment for the skb linear buffer only if
643                          * it contains data */
644                         if (*lso_header_size < skb_headlen(skb))
645                                 real_size += DS_SIZE;
646                         else {
647                                 if (netif_msg_tx_err(priv))
648                                         en_warn(priv, "Non-linear headers\n");
649                                 return 0;
650                         }
651                 }
652         } else {
653                 *lso_header_size = 0;
654                 *inline_ok = is_inline(priv->prof->inline_thold, skb,
655                                        shinfo, pfrag);
656
657                 if (*inline_ok)
658                         real_size = inline_size(skb);
659                 else
660                         real_size = CTRL_SIZE +
661                                     (shinfo->nr_frags + 1) * DS_SIZE;
662         }
663
664         return real_size;
665 }
666
667 static void build_inline_wqe(struct mlx4_en_tx_desc *tx_desc,
668                              const struct sk_buff *skb,
669                              const struct skb_shared_info *shinfo,
670                              void *fragptr)
671 {
672         struct mlx4_wqe_inline_seg *inl = &tx_desc->inl;
673         int spc = MLX4_INLINE_ALIGN - CTRL_SIZE - sizeof(*inl);
674         unsigned int hlen = skb_headlen(skb);
675
676         if (skb->len <= spc) {
677                 if (likely(skb->len >= MIN_PKT_LEN)) {
678                         inl->byte_count = cpu_to_be32(1 << 31 | skb->len);
679                 } else {
680                         inl->byte_count = cpu_to_be32(1 << 31 | MIN_PKT_LEN);
681                         memset(((void *)(inl + 1)) + skb->len, 0,
682                                MIN_PKT_LEN - skb->len);
683                 }
684                 skb_copy_from_linear_data(skb, inl + 1, hlen);
685                 if (shinfo->nr_frags)
686                         memcpy(((void *)(inl + 1)) + hlen, fragptr,
687                                skb_frag_size(&shinfo->frags[0]));
688
689         } else {
690                 inl->byte_count = cpu_to_be32(1 << 31 | spc);
691                 if (hlen <= spc) {
692                         skb_copy_from_linear_data(skb, inl + 1, hlen);
693                         if (hlen < spc) {
694                                 memcpy(((void *)(inl + 1)) + hlen,
695                                        fragptr, spc - hlen);
696                                 fragptr +=  spc - hlen;
697                         }
698                         inl = (void *) (inl + 1) + spc;
699                         memcpy(((void *)(inl + 1)), fragptr, skb->len - spc);
700                 } else {
701                         skb_copy_from_linear_data(skb, inl + 1, spc);
702                         inl = (void *) (inl + 1) + spc;
703                         skb_copy_from_linear_data_offset(skb, spc, inl + 1,
704                                                          hlen - spc);
705                         if (shinfo->nr_frags)
706                                 memcpy(((void *)(inl + 1)) + hlen - spc,
707                                        fragptr,
708                                        skb_frag_size(&shinfo->frags[0]));
709                 }
710
711                 dma_wmb();
712                 inl->byte_count = cpu_to_be32(1 << 31 | (skb->len - spc));
713         }
714 }
715
716 u16 mlx4_en_select_queue(struct net_device *dev, struct sk_buff *skb,
717                          void *accel_priv, select_queue_fallback_t fallback)
718 {
719         struct mlx4_en_priv *priv = netdev_priv(dev);
720         u16 rings_p_up = priv->num_tx_rings_p_up;
721
722         if (netdev_get_num_tc(dev))
723                 return skb_tx_hash(dev, skb);
724
725         return fallback(dev, skb) % rings_p_up;
726 }
727
728 static void mlx4_bf_copy(void __iomem *dst, const void *src,
729                          unsigned int bytecnt)
730 {
731         __iowrite64_copy(dst, src, bytecnt / 8);
732 }
733
734 void mlx4_en_xmit_doorbell(struct mlx4_en_tx_ring *ring)
735 {
736         wmb();
737         /* Since there is no iowrite*_native() that writes the
738          * value as is, without byteswapping - using the one
739          * the doesn't do byteswapping in the relevant arch
740          * endianness.
741          */
742 #if defined(__LITTLE_ENDIAN)
743         iowrite32(
744 #else
745         iowrite32be(
746 #endif
747                   ring->doorbell_qpn,
748                   ring->bf.uar->map + MLX4_SEND_DOORBELL);
749 }
750
751 static void mlx4_en_tx_write_desc(struct mlx4_en_tx_ring *ring,
752                                   struct mlx4_en_tx_desc *tx_desc,
753                                   union mlx4_wqe_qpn_vlan qpn_vlan,
754                                   int desc_size, int bf_index,
755                                   __be32 op_own, bool bf_ok,
756                                   bool send_doorbell)
757 {
758         tx_desc->ctrl.qpn_vlan = qpn_vlan;
759
760         if (bf_ok) {
761                 op_own |= htonl((bf_index & 0xffff) << 8);
762                 /* Ensure new descriptor hits memory
763                  * before setting ownership of this descriptor to HW
764                  */
765                 dma_wmb();
766                 tx_desc->ctrl.owner_opcode = op_own;
767
768                 wmb();
769
770                 mlx4_bf_copy(ring->bf.reg + ring->bf.offset, &tx_desc->ctrl,
771                              desc_size);
772
773                 wmb();
774
775                 ring->bf.offset ^= ring->bf.buf_size;
776         } else {
777                 /* Ensure new descriptor hits memory
778                  * before setting ownership of this descriptor to HW
779                  */
780                 dma_wmb();
781                 tx_desc->ctrl.owner_opcode = op_own;
782                 if (send_doorbell)
783                         mlx4_en_xmit_doorbell(ring);
784                 else
785                         ring->xmit_more++;
786         }
787 }
788
789 static bool mlx4_en_build_dma_wqe(struct mlx4_en_priv *priv,
790                                   struct skb_shared_info *shinfo,
791                                   struct mlx4_wqe_data_seg *data,
792                                   struct sk_buff *skb,
793                                   int lso_header_size,
794                                   __be32 mr_key,
795                                   struct mlx4_en_tx_info *tx_info)
796 {
797         struct device *ddev = priv->ddev;
798         dma_addr_t dma = 0;
799         u32 byte_count = 0;
800         int i_frag;
801
802         /* Map fragments if any */
803         for (i_frag = shinfo->nr_frags - 1; i_frag >= 0; i_frag--) {
804                 const struct skb_frag_struct *frag;
805
806                 frag = &shinfo->frags[i_frag];
807                 byte_count = skb_frag_size(frag);
808                 dma = skb_frag_dma_map(ddev, frag,
809                                        0, byte_count,
810                                        DMA_TO_DEVICE);
811                 if (dma_mapping_error(ddev, dma))
812                         goto tx_drop_unmap;
813
814                 data->addr = cpu_to_be64(dma);
815                 data->lkey = mr_key;
816                 dma_wmb();
817                 data->byte_count = cpu_to_be32(byte_count);
818                 --data;
819         }
820
821         /* Map linear part if needed */
822         if (tx_info->linear) {
823                 byte_count = skb_headlen(skb) - lso_header_size;
824
825                 dma = dma_map_single(ddev, skb->data +
826                                      lso_header_size, byte_count,
827                                      PCI_DMA_TODEVICE);
828                 if (dma_mapping_error(ddev, dma))
829                         goto tx_drop_unmap;
830
831                 data->addr = cpu_to_be64(dma);
832                 data->lkey = mr_key;
833                 dma_wmb();
834                 data->byte_count = cpu_to_be32(byte_count);
835         }
836         /* tx completion can avoid cache line miss for common cases */
837         tx_info->map0_dma = dma;
838         tx_info->map0_byte_count = byte_count;
839
840         return true;
841
842 tx_drop_unmap:
843         en_err(priv, "DMA mapping error\n");
844
845         while (++i_frag < shinfo->nr_frags) {
846                 ++data;
847                 dma_unmap_page(ddev, (dma_addr_t)be64_to_cpu(data->addr),
848                                be32_to_cpu(data->byte_count),
849                                PCI_DMA_TODEVICE);
850         }
851
852         return false;
853 }
854
855 netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
856 {
857         struct skb_shared_info *shinfo = skb_shinfo(skb);
858         struct mlx4_en_priv *priv = netdev_priv(dev);
859         union mlx4_wqe_qpn_vlan qpn_vlan = {};
860         struct mlx4_en_tx_ring *ring;
861         struct mlx4_en_tx_desc *tx_desc;
862         struct mlx4_wqe_data_seg *data;
863         struct mlx4_en_tx_info *tx_info;
864         u32 __maybe_unused ring_cons;
865         int tx_ind;
866         int nr_txbb;
867         int desc_size;
868         int real_size;
869         u32 index, bf_index;
870         __be32 op_own;
871         int lso_header_size;
872         void *fragptr = NULL;
873         bool bounce = false;
874         bool send_doorbell;
875         bool stop_queue;
876         bool inline_ok;
877         u8 data_offset;
878         bool bf_ok;
879
880         tx_ind = skb_get_queue_mapping(skb);
881         ring = priv->tx_ring[TX][tx_ind];
882
883         if (unlikely(!priv->port_up))
884                 goto tx_drop;
885
886         /* fetch ring->cons far ahead before needing it to avoid stall */
887         ring_cons = ACCESS_ONCE(ring->cons);
888
889         real_size = get_real_size(skb, shinfo, dev, &lso_header_size,
890                                   &inline_ok, &fragptr);
891         if (unlikely(!real_size))
892                 goto tx_drop_count;
893
894         /* Align descriptor to TXBB size */
895         desc_size = ALIGN(real_size, TXBB_SIZE);
896         nr_txbb = desc_size >> LOG_TXBB_SIZE;
897         if (unlikely(nr_txbb > MAX_DESC_TXBBS)) {
898                 if (netif_msg_tx_err(priv))
899                         en_warn(priv, "Oversized header or SG list\n");
900                 goto tx_drop_count;
901         }
902
903         bf_ok = ring->bf_enabled;
904         if (skb_vlan_tag_present(skb)) {
905                 u16 vlan_proto;
906
907                 qpn_vlan.vlan_tag = cpu_to_be16(skb_vlan_tag_get(skb));
908                 vlan_proto = be16_to_cpu(skb->vlan_proto);
909                 if (vlan_proto == ETH_P_8021AD)
910                         qpn_vlan.ins_vlan = MLX4_WQE_CTRL_INS_SVLAN;
911                 else if (vlan_proto == ETH_P_8021Q)
912                         qpn_vlan.ins_vlan = MLX4_WQE_CTRL_INS_CVLAN;
913                 else
914                         qpn_vlan.ins_vlan = 0;
915                 bf_ok = false;
916         }
917
918         netdev_txq_bql_enqueue_prefetchw(ring->tx_queue);
919
920         /* Track current inflight packets for performance analysis */
921         AVG_PERF_COUNTER(priv->pstats.inflight_avg,
922                          (u32)(ring->prod - ring_cons - 1));
923
924         /* Packet is good - grab an index and transmit it */
925         index = ring->prod & ring->size_mask;
926         bf_index = ring->prod;
927
928         /* See if we have enough space for whole descriptor TXBB for setting
929          * SW ownership on next descriptor; if not, use a bounce buffer. */
930         if (likely(index + nr_txbb <= ring->size))
931                 tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
932         else {
933                 tx_desc = (struct mlx4_en_tx_desc *) ring->bounce_buf;
934                 bounce = true;
935                 bf_ok = false;
936         }
937
938         /* Save skb in tx_info ring */
939         tx_info = &ring->tx_info[index];
940         tx_info->skb = skb;
941         tx_info->nr_txbb = nr_txbb;
942
943         if (!lso_header_size) {
944                 data = &tx_desc->data;
945                 data_offset = offsetof(struct mlx4_en_tx_desc, data);
946         } else {
947                 int lso_align = ALIGN(lso_header_size + 4, DS_SIZE);
948
949                 data = (void *)&tx_desc->lso + lso_align;
950                 data_offset = offsetof(struct mlx4_en_tx_desc, lso) + lso_align;
951         }
952
953         /* valid only for none inline segments */
954         tx_info->data_offset = data_offset;
955
956         tx_info->inl = inline_ok;
957
958         tx_info->linear = lso_header_size < skb_headlen(skb) && !inline_ok;
959
960         tx_info->nr_maps = shinfo->nr_frags + tx_info->linear;
961         data += tx_info->nr_maps - 1;
962
963         if (!tx_info->inl)
964                 if (!mlx4_en_build_dma_wqe(priv, shinfo, data, skb,
965                                            lso_header_size, ring->mr_key,
966                                            tx_info))
967                         goto tx_drop_count;
968
969         /*
970          * For timestamping add flag to skb_shinfo and
971          * set flag for further reference
972          */
973         tx_info->ts_requested = 0;
974         if (unlikely(ring->hwtstamp_tx_type == HWTSTAMP_TX_ON &&
975                      shinfo->tx_flags & SKBTX_HW_TSTAMP)) {
976                 shinfo->tx_flags |= SKBTX_IN_PROGRESS;
977                 tx_info->ts_requested = 1;
978         }
979
980         /* Prepare ctrl segement apart opcode+ownership, which depends on
981          * whether LSO is used */
982         tx_desc->ctrl.srcrb_flags = priv->ctrl_flags;
983         if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
984                 if (!skb->encapsulation)
985                         tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM |
986                                                                  MLX4_WQE_CTRL_TCP_UDP_CSUM);
987                 else
988                         tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM);
989                 ring->tx_csum++;
990         }
991
992         if (priv->flags & MLX4_EN_FLAG_ENABLE_HW_LOOPBACK) {
993                 struct ethhdr *ethh;
994
995                 /* Copy dst mac address to wqe. This allows loopback in eSwitch,
996                  * so that VFs and PF can communicate with each other
997                  */
998                 ethh = (struct ethhdr *)skb->data;
999                 tx_desc->ctrl.srcrb_flags16[0] = get_unaligned((__be16 *)ethh->h_dest);
1000                 tx_desc->ctrl.imm = get_unaligned((__be32 *)(ethh->h_dest + 2));
1001         }
1002
1003         /* Handle LSO (TSO) packets */
1004         if (lso_header_size) {
1005                 int i;
1006
1007                 /* Mark opcode as LSO */
1008                 op_own = cpu_to_be32(MLX4_OPCODE_LSO | (1 << 6)) |
1009                         ((ring->prod & ring->size) ?
1010                                 cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1011
1012                 /* Fill in the LSO prefix */
1013                 tx_desc->lso.mss_hdr_size = cpu_to_be32(
1014                         shinfo->gso_size << 16 | lso_header_size);
1015
1016                 /* Copy headers;
1017                  * note that we already verified that it is linear */
1018                 memcpy(tx_desc->lso.header, skb->data, lso_header_size);
1019
1020                 ring->tso_packets++;
1021
1022                 i = shinfo->gso_segs;
1023                 tx_info->nr_bytes = skb->len + (i - 1) * lso_header_size;
1024                 ring->packets += i;
1025         } else {
1026                 /* Normal (Non LSO) packet */
1027                 op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
1028                         ((ring->prod & ring->size) ?
1029                          cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1030                 tx_info->nr_bytes = max_t(unsigned int, skb->len, ETH_ZLEN);
1031                 ring->packets++;
1032         }
1033         ring->bytes += tx_info->nr_bytes;
1034         netdev_tx_sent_queue(ring->tx_queue, tx_info->nr_bytes);
1035         AVG_PERF_COUNTER(priv->pstats.tx_pktsz_avg, skb->len);
1036
1037         if (tx_info->inl)
1038                 build_inline_wqe(tx_desc, skb, shinfo, fragptr);
1039
1040         if (skb->encapsulation) {
1041                 union {
1042                         struct iphdr *v4;
1043                         struct ipv6hdr *v6;
1044                         unsigned char *hdr;
1045                 } ip;
1046                 u8 proto;
1047
1048                 ip.hdr = skb_inner_network_header(skb);
1049                 proto = (ip.v4->version == 4) ? ip.v4->protocol :
1050                                                 ip.v6->nexthdr;
1051
1052                 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
1053                         op_own |= cpu_to_be32(MLX4_WQE_CTRL_IIP | MLX4_WQE_CTRL_ILP);
1054                 else
1055                         op_own |= cpu_to_be32(MLX4_WQE_CTRL_IIP);
1056         }
1057
1058         ring->prod += nr_txbb;
1059
1060         /* If we used a bounce buffer then copy descriptor back into place */
1061         if (unlikely(bounce))
1062                 tx_desc = mlx4_en_bounce_to_desc(priv, ring, index, desc_size);
1063
1064         skb_tx_timestamp(skb);
1065
1066         /* Check available TXBBs And 2K spare for prefetch */
1067         stop_queue = mlx4_en_is_tx_ring_full(ring);
1068         if (unlikely(stop_queue)) {
1069                 netif_tx_stop_queue(ring->tx_queue);
1070                 ring->queue_stopped++;
1071         }
1072         send_doorbell = !skb->xmit_more || netif_xmit_stopped(ring->tx_queue);
1073
1074         real_size = (real_size / 16) & 0x3f;
1075
1076         bf_ok &= desc_size <= MAX_BF && send_doorbell;
1077
1078         if (bf_ok)
1079                 qpn_vlan.bf_qpn = ring->doorbell_qpn | cpu_to_be32(real_size);
1080         else
1081                 qpn_vlan.fence_size = real_size;
1082
1083         mlx4_en_tx_write_desc(ring, tx_desc, qpn_vlan, desc_size, bf_index,
1084                               op_own, bf_ok, send_doorbell);
1085
1086         if (unlikely(stop_queue)) {
1087                 /* If queue was emptied after the if (stop_queue) , and before
1088                  * the netif_tx_stop_queue() - need to wake the queue,
1089                  * or else it will remain stopped forever.
1090                  * Need a memory barrier to make sure ring->cons was not
1091                  * updated before queue was stopped.
1092                  */
1093                 smp_rmb();
1094
1095                 ring_cons = ACCESS_ONCE(ring->cons);
1096                 if (unlikely(!mlx4_en_is_tx_ring_full(ring))) {
1097                         netif_tx_wake_queue(ring->tx_queue);
1098                         ring->wake_queue++;
1099                 }
1100         }
1101         return NETDEV_TX_OK;
1102
1103 tx_drop_count:
1104         ring->tx_dropped++;
1105 tx_drop:
1106         dev_kfree_skb_any(skb);
1107         return NETDEV_TX_OK;
1108 }
1109
1110 #define MLX4_EN_XDP_TX_NRTXBB  1
1111 #define MLX4_EN_XDP_TX_REAL_SZ (((CTRL_SIZE + MLX4_EN_XDP_TX_NRTXBB * DS_SIZE) \
1112                                  / 16) & 0x3f)
1113
1114 netdev_tx_t mlx4_en_xmit_frame(struct mlx4_en_rx_ring *rx_ring,
1115                                struct mlx4_en_rx_alloc *frame,
1116                                struct net_device *dev, unsigned int length,
1117                                int tx_ind, bool *doorbell_pending)
1118 {
1119         struct mlx4_en_priv *priv = netdev_priv(dev);
1120         union mlx4_wqe_qpn_vlan qpn_vlan = {};
1121         struct mlx4_en_tx_desc *tx_desc;
1122         struct mlx4_en_tx_info *tx_info;
1123         struct mlx4_wqe_data_seg *data;
1124         struct mlx4_en_tx_ring *ring;
1125         dma_addr_t dma;
1126         __be32 op_own;
1127         int index;
1128
1129         if (unlikely(!priv->port_up))
1130                 goto tx_drop;
1131
1132         ring = priv->tx_ring[TX_XDP][tx_ind];
1133
1134         if (unlikely(mlx4_en_is_tx_ring_full(ring)))
1135                 goto tx_drop_count;
1136
1137         index = ring->prod & ring->size_mask;
1138         tx_info = &ring->tx_info[index];
1139
1140         /* Track current inflight packets for performance analysis */
1141         AVG_PERF_COUNTER(priv->pstats.inflight_avg,
1142                          (u32)(ring->prod - READ_ONCE(ring->cons) - 1));
1143
1144         tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
1145         data = &tx_desc->data;
1146
1147         dma = frame->dma;
1148
1149         tx_info->page = frame->page;
1150         frame->page = NULL;
1151         tx_info->map0_dma = dma;
1152         tx_info->map0_byte_count = PAGE_SIZE;
1153         tx_info->nr_txbb = MLX4_EN_XDP_TX_NRTXBB;
1154         tx_info->nr_bytes = max_t(unsigned int, length, ETH_ZLEN);
1155         tx_info->data_offset = offsetof(struct mlx4_en_tx_desc, data);
1156         tx_info->ts_requested = 0;
1157         tx_info->nr_maps = 1;
1158         tx_info->linear = 1;
1159         tx_info->inl = 0;
1160
1161         dma_sync_single_range_for_device(priv->ddev, dma, frame->page_offset,
1162                                          length, PCI_DMA_TODEVICE);
1163
1164         data->addr = cpu_to_be64(dma + frame->page_offset);
1165         data->lkey = ring->mr_key;
1166         dma_wmb();
1167         data->byte_count = cpu_to_be32(length);
1168
1169         /* tx completion can avoid cache line miss for common cases */
1170         tx_desc->ctrl.srcrb_flags = priv->ctrl_flags;
1171
1172         op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
1173                 ((ring->prod & ring->size) ?
1174                  cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1175
1176         rx_ring->xdp_tx++;
1177         AVG_PERF_COUNTER(priv->pstats.tx_pktsz_avg, length);
1178
1179         ring->prod += MLX4_EN_XDP_TX_NRTXBB;
1180
1181         qpn_vlan.fence_size = MLX4_EN_XDP_TX_REAL_SZ;
1182
1183         mlx4_en_tx_write_desc(ring, tx_desc, qpn_vlan, TXBB_SIZE, 0,
1184                               op_own, false, false);
1185         *doorbell_pending = true;
1186
1187         return NETDEV_TX_OK;
1188
1189 tx_drop_count:
1190         rx_ring->xdp_tx_full++;
1191         *doorbell_pending = true;
1192 tx_drop:
1193         return NETDEV_TX_BUSY;
1194 }