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/indirect_call_wrapper.h>
46#include <net/ipv6.h>
47
48#include "mlx4_en.h"
49
50int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv,
51 struct mlx4_en_tx_ring **pring, u32 size,
52 u16 stride, int node, int queue_index)
53{
54 struct mlx4_en_dev *mdev = priv->mdev;
55 struct mlx4_en_tx_ring *ring;
56 int tmp;
57 int err;
58
59 ring = kzalloc_node(size: sizeof(*ring), GFP_KERNEL, node);
60 if (!ring) {
61 en_err(priv, "Failed allocating TX ring\n");
62 return -ENOMEM;
63 }
64
65 ring->size = size;
66 ring->size_mask = size - 1;
67 ring->sp_stride = stride;
68 ring->full_size = ring->size - HEADROOM - MLX4_MAX_DESC_TXBBS;
69
70 tmp = size * sizeof(struct mlx4_en_tx_info);
71 ring->tx_info = kvmalloc_node(size: tmp, GFP_KERNEL, node);
72 if (!ring->tx_info) {
73 err = -ENOMEM;
74 goto err_ring;
75 }
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_node(MLX4_TX_BOUNCE_BUFFER_SIZE,
81 GFP_KERNEL, node);
82 if (!ring->bounce_buf) {
83 ring->bounce_buf = kmalloc(MLX4_TX_BOUNCE_BUFFER_SIZE,
84 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(dev: &mdev->dev->persist->pdev->dev, node);
94 err = mlx4_alloc_hwq_res(dev: mdev->dev, wqres: &ring->sp_wqres, size: ring->buf_size);
95 set_dev_node(dev: &mdev->dev->persist->pdev->dev, node: 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(dev: mdev->dev, cnt: 1, align: 1, base: &ring->qpn,
108 flags: MLX4_RESERVE_ETH_BF_QP,
109 usage: 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(dev: mdev->dev, qpn: ring->qpn, qp: &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(dev: mdev->dev, bf: &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 ring->doorbell_address = ring->bf.uar->map + MLX4_SEND_DOORBELL;
136
137 ring->hwtstamp_tx_type = priv->hwtstamp_config.tx_type;
138 ring->queue_index = queue_index;
139
140 if (queue_index < priv->num_tx_rings_p_up)
141 cpumask_set_cpu(cpu: cpumask_local_spread(i: queue_index,
142 node: priv->mdev->dev->numa_node),
143 dstp: &ring->sp_affinity_mask);
144
145 *pring = ring;
146 return 0;
147
148err_reserve:
149 mlx4_qp_release_range(dev: mdev->dev, base_qpn: ring->qpn, cnt: 1);
150err_hwq_res:
151 mlx4_free_hwq_res(mdev: mdev->dev, wqres: &ring->sp_wqres, size: ring->buf_size);
152err_bounce:
153 kfree(objp: ring->bounce_buf);
154 ring->bounce_buf = NULL;
155err_info:
156 kvfree(addr: ring->tx_info);
157 ring->tx_info = NULL;
158err_ring:
159 kfree(objp: ring);
160 *pring = NULL;
161 return err;
162}
163
164void mlx4_en_destroy_tx_ring(struct mlx4_en_priv *priv,
165 struct mlx4_en_tx_ring **pring)
166{
167 struct mlx4_en_dev *mdev = priv->mdev;
168 struct mlx4_en_tx_ring *ring = *pring;
169 en_dbg(DRV, priv, "Destroying tx ring, qpn: %d\n", ring->qpn);
170
171 if (ring->bf_alloced)
172 mlx4_bf_free(dev: mdev->dev, bf: &ring->bf);
173 mlx4_qp_remove(dev: mdev->dev, qp: &ring->sp_qp);
174 mlx4_qp_free(dev: mdev->dev, qp: &ring->sp_qp);
175 mlx4_qp_release_range(dev: priv->mdev->dev, base_qpn: ring->qpn, cnt: 1);
176 mlx4_free_hwq_res(mdev: mdev->dev, wqres: &ring->sp_wqres, size: ring->buf_size);
177 kfree(objp: ring->bounce_buf);
178 ring->bounce_buf = NULL;
179 kvfree(addr: ring->tx_info);
180 ring->tx_info = NULL;
181 kfree(objp: ring);
182 *pring = NULL;
183}
184
185int mlx4_en_activate_tx_ring(struct mlx4_en_priv *priv,
186 struct mlx4_en_tx_ring *ring,
187 int cq, int user_prio)
188{
189 struct mlx4_en_dev *mdev = priv->mdev;
190 int err;
191
192 ring->sp_cqn = cq;
193 ring->prod = 0;
194 ring->cons = 0xffffffff;
195 ring->last_nr_txbb = 1;
196 memset(ring->tx_info, 0, ring->size * sizeof(struct mlx4_en_tx_info));
197 memset(ring->buf, 0, ring->buf_size);
198 ring->free_tx_desc = mlx4_en_free_tx_desc;
199
200 ring->sp_qp_state = MLX4_QP_STATE_RST;
201 ring->doorbell_qpn = cpu_to_be32(ring->sp_qp.qpn << 8);
202 ring->mr_key = cpu_to_be32(mdev->mr.key);
203
204 mlx4_en_fill_qp_context(priv, size: ring->size, stride: ring->sp_stride, is_tx: 1, rss: 0, qpn: ring->qpn,
205 cqn: ring->sp_cqn, user_prio, context: &ring->sp_context);
206 if (ring->bf_alloced)
207 ring->sp_context.usr_page =
208 cpu_to_be32(mlx4_to_hw_uar_index(mdev->dev,
209 ring->bf.uar->index));
210
211 err = mlx4_qp_to_ready(dev: mdev->dev, mtt: &ring->sp_wqres.mtt, context: &ring->sp_context,
212 qp: &ring->sp_qp, qp_state: &ring->sp_qp_state);
213 if (!cpumask_empty(srcp: &ring->sp_affinity_mask))
214 netif_set_xps_queue(dev: priv->dev, mask: &ring->sp_affinity_mask,
215 index: ring->queue_index);
216
217 return err;
218}
219
220void mlx4_en_deactivate_tx_ring(struct mlx4_en_priv *priv,
221 struct mlx4_en_tx_ring *ring)
222{
223 struct mlx4_en_dev *mdev = priv->mdev;
224
225 mlx4_qp_modify(dev: mdev->dev, NULL, cur_state: ring->sp_qp_state,
226 new_state: MLX4_QP_STATE_RST, NULL, optpar: 0, sqd_event: 0, qp: &ring->sp_qp);
227}
228
229static inline bool mlx4_en_is_tx_ring_full(struct mlx4_en_tx_ring *ring)
230{
231 u32 used = READ_ONCE(ring->prod) - READ_ONCE(ring->cons);
232
233 return used > ring->full_size;
234}
235
236static void mlx4_en_stamp_wqe(struct mlx4_en_priv *priv,
237 struct mlx4_en_tx_ring *ring, int index,
238 u8 owner)
239{
240 __be32 stamp = cpu_to_be32(STAMP_VAL | (!!owner << STAMP_SHIFT));
241 struct mlx4_en_tx_desc *tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
242 struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
243 void *end = ring->buf + ring->buf_size;
244 __be32 *ptr = (__be32 *)tx_desc;
245 int i;
246
247 /* Optimize the common case when there are no wraparounds */
248 if (likely((void *)tx_desc +
249 (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) {
250 /* Stamp the freed descriptor */
251 for (i = 0; i < tx_info->nr_txbb << LOG_TXBB_SIZE;
252 i += STAMP_STRIDE) {
253 *ptr = stamp;
254 ptr += STAMP_DWORDS;
255 }
256 } else {
257 /* Stamp the freed descriptor */
258 for (i = 0; i < tx_info->nr_txbb << LOG_TXBB_SIZE;
259 i += STAMP_STRIDE) {
260 *ptr = stamp;
261 ptr += STAMP_DWORDS;
262 if ((void *)ptr >= end) {
263 ptr = ring->buf;
264 stamp ^= cpu_to_be32(0x80000000);
265 }
266 }
267 }
268}
269
270INDIRECT_CALLABLE_DECLARE(u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
271 struct mlx4_en_tx_ring *ring,
272 int index, u64 timestamp,
273 int napi_mode));
274
275u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
276 struct mlx4_en_tx_ring *ring,
277 int index, u64 timestamp,
278 int napi_mode)
279{
280 struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
281 struct mlx4_en_tx_desc *tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
282 struct mlx4_wqe_data_seg *data = (void *) tx_desc + tx_info->data_offset;
283 void *end = ring->buf + ring->buf_size;
284 struct sk_buff *skb = tx_info->skb;
285 int nr_maps = tx_info->nr_maps;
286 int i;
287
288 /* We do not touch skb here, so prefetch skb->users location
289 * to speedup consume_skb()
290 */
291 prefetchw(x: &skb->users);
292
293 if (unlikely(timestamp)) {
294 struct skb_shared_hwtstamps hwts;
295
296 mlx4_en_fill_hwtstamps(mdev: priv->mdev, hwts: &hwts, timestamp);
297 skb_tstamp_tx(orig_skb: skb, hwtstamps: &hwts);
298 }
299
300 if (!tx_info->inl) {
301 if (tx_info->linear)
302 dma_unmap_single(priv->ddev,
303 tx_info->map0_dma,
304 tx_info->map0_byte_count,
305 DMA_TO_DEVICE);
306 else
307 dma_unmap_page(priv->ddev,
308 tx_info->map0_dma,
309 tx_info->map0_byte_count,
310 DMA_TO_DEVICE);
311 /* Optimize the common case when there are no wraparounds */
312 if (likely((void *)tx_desc +
313 (tx_info->nr_txbb << LOG_TXBB_SIZE) <= end)) {
314 for (i = 1; i < nr_maps; i++) {
315 data++;
316 dma_unmap_page(priv->ddev,
317 (dma_addr_t)be64_to_cpu(data->addr),
318 be32_to_cpu(data->byte_count),
319 DMA_TO_DEVICE);
320 }
321 } else {
322 if ((void *)data >= end)
323 data = ring->buf + ((void *)data - end);
324
325 for (i = 1; i < nr_maps; i++) {
326 data++;
327 /* Check for wraparound before unmapping */
328 if ((void *) data >= end)
329 data = ring->buf;
330 dma_unmap_page(priv->ddev,
331 (dma_addr_t)be64_to_cpu(data->addr),
332 be32_to_cpu(data->byte_count),
333 DMA_TO_DEVICE);
334 }
335 }
336 }
337 napi_consume_skb(skb, budget: napi_mode);
338
339 return tx_info->nr_txbb;
340}
341
342INDIRECT_CALLABLE_DECLARE(u32 mlx4_en_recycle_tx_desc(struct mlx4_en_priv *priv,
343 struct mlx4_en_tx_ring *ring,
344 int index, u64 timestamp,
345 int napi_mode));
346
347u32 mlx4_en_recycle_tx_desc(struct mlx4_en_priv *priv,
348 struct mlx4_en_tx_ring *ring,
349 int index, u64 timestamp,
350 int napi_mode)
351{
352 struct mlx4_en_tx_info *tx_info = &ring->tx_info[index];
353 struct mlx4_en_rx_alloc frame = {
354 .page = tx_info->page,
355 .dma = tx_info->map0_dma,
356 };
357
358 if (!napi_mode || !mlx4_en_rx_recycle(ring: ring->recycle_ring, frame: &frame)) {
359 dma_unmap_page(priv->ddev, tx_info->map0_dma,
360 PAGE_SIZE, priv->dma_dir);
361 put_page(page: tx_info->page);
362 }
363
364 return tx_info->nr_txbb;
365}
366
367int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring)
368{
369 struct mlx4_en_priv *priv = netdev_priv(dev);
370 int cnt = 0;
371
372 /* Skip last polled descriptor */
373 ring->cons += ring->last_nr_txbb;
374 en_dbg(DRV, priv, "Freeing Tx buf - cons:0x%x prod:0x%x\n",
375 ring->cons, ring->prod);
376
377 if ((u32) (ring->prod - ring->cons) > ring->size) {
378 if (netif_msg_tx_err(priv))
379 en_warn(priv, "Tx consumer passed producer!\n");
380 return 0;
381 }
382
383 while (ring->cons != ring->prod) {
384 ring->last_nr_txbb = ring->free_tx_desc(priv, ring,
385 ring->cons & ring->size_mask,
386 0, 0 /* Non-NAPI caller */);
387 ring->cons += ring->last_nr_txbb;
388 cnt++;
389 }
390
391 if (ring->tx_queue)
392 netdev_tx_reset_queue(q: ring->tx_queue);
393
394 if (cnt)
395 en_dbg(DRV, priv, "Freed %d uncompleted tx descriptors\n", cnt);
396
397 return cnt;
398}
399
400static void mlx4_en_handle_err_cqe(struct mlx4_en_priv *priv, struct mlx4_err_cqe *err_cqe,
401 u16 cqe_index, struct mlx4_en_tx_ring *ring)
402{
403 struct mlx4_en_dev *mdev = priv->mdev;
404 struct mlx4_en_tx_info *tx_info;
405 struct mlx4_en_tx_desc *tx_desc;
406 u16 wqe_index;
407 int desc_size;
408
409 en_err(priv, "CQE error - cqn 0x%x, ci 0x%x, vendor syndrome: 0x%x syndrome: 0x%x\n",
410 ring->sp_cqn, cqe_index, err_cqe->vendor_err_syndrome, err_cqe->syndrome);
411 print_hex_dump(KERN_WARNING, prefix_str: "", prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1, buf: err_cqe, len: sizeof(*err_cqe),
412 ascii: false);
413
414 wqe_index = be16_to_cpu(err_cqe->wqe_index) & ring->size_mask;
415 tx_info = &ring->tx_info[wqe_index];
416 desc_size = tx_info->nr_txbb << LOG_TXBB_SIZE;
417 en_err(priv, "Related WQE - qpn 0x%x, wqe index 0x%x, wqe size 0x%x\n", ring->qpn,
418 wqe_index, desc_size);
419 tx_desc = ring->buf + (wqe_index << LOG_TXBB_SIZE);
420 print_hex_dump(KERN_WARNING, prefix_str: "", prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1, buf: tx_desc, len: desc_size, ascii: false);
421
422 if (test_and_set_bit(nr: MLX4_EN_STATE_FLAG_RESTARTING, addr: &priv->state))
423 return;
424
425 en_err(priv, "Scheduling port restart\n");
426 queue_work(wq: mdev->workqueue, work: &priv->restart_task);
427}
428
429int mlx4_en_process_tx_cq(struct net_device *dev,
430 struct mlx4_en_cq *cq, int napi_budget)
431{
432 struct mlx4_en_priv *priv = netdev_priv(dev);
433 struct mlx4_cq *mcq = &cq->mcq;
434 struct mlx4_en_tx_ring *ring = priv->tx_ring[cq->type][cq->ring];
435 struct mlx4_cqe *cqe;
436 u16 index, ring_index, stamp_index;
437 u32 txbbs_skipped = 0;
438 u32 txbbs_stamp = 0;
439 u32 cons_index = mcq->cons_index;
440 int size = cq->size;
441 u32 size_mask = ring->size_mask;
442 struct mlx4_cqe *buf = cq->buf;
443 u32 packets = 0;
444 u32 bytes = 0;
445 int factor = priv->cqe_factor;
446 int done = 0;
447 int budget = priv->tx_work_limit;
448 u32 last_nr_txbb;
449 u32 ring_cons;
450
451 if (unlikely(!priv->port_up))
452 return 0;
453
454 netdev_txq_bql_complete_prefetchw(dev_queue: ring->tx_queue);
455
456 index = cons_index & size_mask;
457 cqe = mlx4_en_get_cqe(buf, idx: index, cqe_sz: priv->cqe_size) + factor;
458 last_nr_txbb = READ_ONCE(ring->last_nr_txbb);
459 ring_cons = READ_ONCE(ring->cons);
460 ring_index = ring_cons & size_mask;
461 stamp_index = ring_index;
462
463 /* Process all completed CQEs */
464 while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
465 cons_index & size) && (done < budget)) {
466 u16 new_index;
467
468 /*
469 * make sure we read the CQE after we read the
470 * ownership bit
471 */
472 dma_rmb();
473
474 if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
475 MLX4_CQE_OPCODE_ERROR))
476 if (!test_and_set_bit(nr: MLX4_EN_TX_RING_STATE_RECOVERING, addr: &ring->state))
477 mlx4_en_handle_err_cqe(priv, err_cqe: (struct mlx4_err_cqe *)cqe, cqe_index: index,
478 ring);
479
480 /* Skip over last polled CQE */
481 new_index = be16_to_cpu(cqe->wqe_index) & size_mask;
482
483 do {
484 u64 timestamp = 0;
485
486 txbbs_skipped += last_nr_txbb;
487 ring_index = (ring_index + last_nr_txbb) & size_mask;
488
489 if (unlikely(ring->tx_info[ring_index].ts_requested))
490 timestamp = mlx4_en_get_cqe_ts(cqe);
491
492 /* free next descriptor */
493 last_nr_txbb = INDIRECT_CALL_2(ring->free_tx_desc,
494 mlx4_en_free_tx_desc,
495 mlx4_en_recycle_tx_desc,
496 priv, ring, ring_index,
497 timestamp, napi_budget);
498
499 mlx4_en_stamp_wqe(priv, ring, index: stamp_index,
500 owner: !!((ring_cons + txbbs_stamp) &
501 ring->size));
502 stamp_index = ring_index;
503 txbbs_stamp = txbbs_skipped;
504 packets++;
505 bytes += ring->tx_info[ring_index].nr_bytes;
506 } while ((++done < budget) && (ring_index != new_index));
507
508 ++cons_index;
509 index = cons_index & size_mask;
510 cqe = mlx4_en_get_cqe(buf, idx: index, cqe_sz: priv->cqe_size) + factor;
511 }
512
513 /*
514 * To prevent CQ overflow we first update CQ consumer and only then
515 * the ring consumer.
516 */
517 mcq->cons_index = cons_index;
518 mlx4_cq_set_ci(cq: mcq);
519 wmb();
520
521 /* we want to dirty this cache line once */
522 WRITE_ONCE(ring->last_nr_txbb, last_nr_txbb);
523 WRITE_ONCE(ring->cons, ring_cons + txbbs_skipped);
524
525 if (cq->type == TX_XDP)
526 return done;
527
528 netdev_tx_completed_queue(dev_queue: ring->tx_queue, pkts: packets, bytes);
529
530 /* Wakeup Tx queue if this stopped, and ring is not full.
531 */
532 if (netif_tx_queue_stopped(dev_queue: ring->tx_queue) &&
533 !mlx4_en_is_tx_ring_full(ring)) {
534 netif_tx_wake_queue(dev_queue: ring->tx_queue);
535 ring->wake_queue++;
536 }
537
538 return done;
539}
540
541void mlx4_en_tx_irq(struct mlx4_cq *mcq)
542{
543 struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
544 struct mlx4_en_priv *priv = netdev_priv(dev: cq->dev);
545
546 if (likely(priv->port_up))
547 napi_schedule_irqoff(n: &cq->napi);
548 else
549 mlx4_en_arm_cq(priv, cq);
550}
551
552/* TX CQ polling - called by NAPI */
553int mlx4_en_poll_tx_cq(struct napi_struct *napi, int budget)
554{
555 struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
556 struct net_device *dev = cq->dev;
557 struct mlx4_en_priv *priv = netdev_priv(dev);
558 int work_done;
559
560 work_done = mlx4_en_process_tx_cq(dev, cq, napi_budget: budget);
561 if (work_done >= budget)
562 return budget;
563
564 if (napi_complete_done(n: napi, work_done))
565 mlx4_en_arm_cq(priv, cq);
566
567 return 0;
568}
569
570static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
571 struct mlx4_en_tx_ring *ring,
572 u32 index,
573 unsigned int desc_size)
574{
575 u32 copy = (ring->size - index) << LOG_TXBB_SIZE;
576 int i;
577
578 for (i = desc_size - copy - 4; i >= 0; i -= 4) {
579 if ((i & (TXBB_SIZE - 1)) == 0)
580 wmb();
581
582 *((u32 *) (ring->buf + i)) =
583 *((u32 *) (ring->bounce_buf + copy + i));
584 }
585
586 for (i = copy - 4; i >= 4 ; i -= 4) {
587 if ((i & (TXBB_SIZE - 1)) == 0)
588 wmb();
589
590 *((u32 *)(ring->buf + (index << LOG_TXBB_SIZE) + i)) =
591 *((u32 *) (ring->bounce_buf + i));
592 }
593
594 /* Return real descriptor location */
595 return ring->buf + (index << LOG_TXBB_SIZE);
596}
597
598/* Decide if skb can be inlined in tx descriptor to avoid dma mapping
599 *
600 * It seems strange we do not simply use skb_copy_bits().
601 * This would allow to inline all skbs iff skb->len <= inline_thold
602 *
603 * Note that caller already checked skb was not a gso packet
604 */
605static bool is_inline(int inline_thold, const struct sk_buff *skb,
606 const struct skb_shared_info *shinfo,
607 void **pfrag)
608{
609 void *ptr;
610
611 if (skb->len > inline_thold || !inline_thold)
612 return false;
613
614 if (shinfo->nr_frags == 1) {
615 ptr = skb_frag_address_safe(frag: &shinfo->frags[0]);
616 if (unlikely(!ptr))
617 return false;
618 *pfrag = ptr;
619 return true;
620 }
621 if (shinfo->nr_frags)
622 return false;
623 return true;
624}
625
626static int inline_size(const struct sk_buff *skb)
627{
628 if (skb->len + CTRL_SIZE + sizeof(struct mlx4_wqe_inline_seg)
629 <= MLX4_INLINE_ALIGN)
630 return ALIGN(skb->len + CTRL_SIZE +
631 sizeof(struct mlx4_wqe_inline_seg), 16);
632 else
633 return ALIGN(skb->len + CTRL_SIZE + 2 *
634 sizeof(struct mlx4_wqe_inline_seg), 16);
635}
636
637static int get_real_size(const struct sk_buff *skb,
638 const struct skb_shared_info *shinfo,
639 struct net_device *dev,
640 int *lso_header_size,
641 bool *inline_ok,
642 void **pfrag,
643 int *hopbyhop)
644{
645 struct mlx4_en_priv *priv = netdev_priv(dev);
646 int real_size;
647
648 if (shinfo->gso_size) {
649 *inline_ok = false;
650 *hopbyhop = 0;
651 if (skb->encapsulation) {
652 *lso_header_size = skb_inner_tcp_all_headers(skb);
653 } else {
654 /* Detects large IPV6 TCP packets and prepares for removal of
655 * HBH header that has been pushed by ip6_xmit(),
656 * mainly so that tcpdump can dissect them.
657 */
658 if (ipv6_has_hopopt_jumbo(skb))
659 *hopbyhop = sizeof(struct hop_jumbo_hdr);
660 *lso_header_size = skb_tcp_all_headers(skb);
661 }
662 real_size = CTRL_SIZE + shinfo->nr_frags * DS_SIZE +
663 ALIGN(*lso_header_size - *hopbyhop + 4, DS_SIZE);
664 if (unlikely(*lso_header_size != skb_headlen(skb))) {
665 /* We add a segment for the skb linear buffer only if
666 * it contains data */
667 if (*lso_header_size < skb_headlen(skb))
668 real_size += DS_SIZE;
669 else {
670 if (netif_msg_tx_err(priv))
671 en_warn(priv, "Non-linear headers\n");
672 return 0;
673 }
674 }
675 } else {
676 *lso_header_size = 0;
677 *inline_ok = is_inline(inline_thold: priv->prof->inline_thold, skb,
678 shinfo, pfrag);
679
680 if (*inline_ok)
681 real_size = inline_size(skb);
682 else
683 real_size = CTRL_SIZE +
684 (shinfo->nr_frags + 1) * DS_SIZE;
685 }
686
687 return real_size;
688}
689
690static void build_inline_wqe(struct mlx4_en_tx_desc *tx_desc,
691 const struct sk_buff *skb,
692 const struct skb_shared_info *shinfo,
693 void *fragptr)
694{
695 struct mlx4_wqe_inline_seg *inl = &tx_desc->inl;
696 int spc = MLX4_INLINE_ALIGN - CTRL_SIZE - sizeof(*inl);
697 unsigned int hlen = skb_headlen(skb);
698
699 if (skb->len <= spc) {
700 if (likely(skb->len >= MIN_PKT_LEN)) {
701 inl->byte_count = cpu_to_be32(1 << 31 | skb->len);
702 } else {
703 inl->byte_count = cpu_to_be32(1 << 31 | MIN_PKT_LEN);
704 memset(inl->data + skb->len, 0,
705 MIN_PKT_LEN - skb->len);
706 }
707 skb_copy_from_linear_data(skb, inl->data, len: hlen);
708 if (shinfo->nr_frags)
709 memcpy(inl->data + hlen, fragptr,
710 skb_frag_size(&shinfo->frags[0]));
711
712 } else {
713 inl->byte_count = cpu_to_be32(1 << 31 | spc);
714 if (hlen <= spc) {
715 skb_copy_from_linear_data(skb, inl->data, len: hlen);
716 if (hlen < spc) {
717 memcpy(inl->data + hlen,
718 fragptr, spc - hlen);
719 fragptr += spc - hlen;
720 }
721 inl = (void *)inl->data + spc;
722 memcpy(inl->data, fragptr, skb->len - spc);
723 } else {
724 skb_copy_from_linear_data(skb, inl->data, len: spc);
725 inl = (void *)inl->data + spc;
726 skb_copy_from_linear_data_offset(skb, offset: spc, inl->data,
727 len: hlen - spc);
728 if (shinfo->nr_frags)
729 memcpy(inl->data + hlen - spc,
730 fragptr,
731 skb_frag_size(&shinfo->frags[0]));
732 }
733
734 dma_wmb();
735 inl->byte_count = cpu_to_be32(1 << 31 | (skb->len - spc));
736 }
737}
738
739u16 mlx4_en_select_queue(struct net_device *dev, struct sk_buff *skb,
740 struct net_device *sb_dev)
741{
742 struct mlx4_en_priv *priv = netdev_priv(dev);
743 u16 rings_p_up = priv->num_tx_rings_p_up;
744
745 if (netdev_get_num_tc(dev))
746 return netdev_pick_tx(dev, skb, NULL);
747
748 return netdev_pick_tx(dev, skb, NULL) % rings_p_up;
749}
750
751static void mlx4_bf_copy(void __iomem *dst, const void *src,
752 unsigned int bytecnt)
753{
754 __iowrite64_copy(to: dst, from: src, count: bytecnt / 8);
755}
756
757void mlx4_en_xmit_doorbell(struct mlx4_en_tx_ring *ring)
758{
759 wmb();
760 /* Since there is no iowrite*_native() that writes the
761 * value as is, without byteswapping - using the one
762 * the doesn't do byteswapping in the relevant arch
763 * endianness.
764 */
765#if defined(__LITTLE_ENDIAN)
766 iowrite32(
767#else
768 iowrite32be(
769#endif
770 (__force u32)ring->doorbell_qpn, ring->doorbell_address);
771}
772
773static void mlx4_en_tx_write_desc(struct mlx4_en_tx_ring *ring,
774 struct mlx4_en_tx_desc *tx_desc,
775 union mlx4_wqe_qpn_vlan qpn_vlan,
776 int desc_size, int bf_index,
777 __be32 op_own, bool bf_ok,
778 bool send_doorbell)
779{
780 tx_desc->ctrl.qpn_vlan = qpn_vlan;
781
782 if (bf_ok) {
783 op_own |= htonl((bf_index & 0xffff) << 8);
784 /* Ensure new descriptor hits memory
785 * before setting ownership of this descriptor to HW
786 */
787 dma_wmb();
788 tx_desc->ctrl.owner_opcode = op_own;
789
790 wmb();
791
792 mlx4_bf_copy(dst: ring->bf.reg + ring->bf.offset, src: &tx_desc->ctrl,
793 bytecnt: desc_size);
794
795 wmb();
796
797 ring->bf.offset ^= ring->bf.buf_size;
798 } else {
799 /* Ensure new descriptor hits memory
800 * before setting ownership of this descriptor to HW
801 */
802 dma_wmb();
803 tx_desc->ctrl.owner_opcode = op_own;
804 if (send_doorbell)
805 mlx4_en_xmit_doorbell(ring);
806 else
807 ring->xmit_more++;
808 }
809}
810
811static bool mlx4_en_build_dma_wqe(struct mlx4_en_priv *priv,
812 struct skb_shared_info *shinfo,
813 struct mlx4_wqe_data_seg *data,
814 struct sk_buff *skb,
815 int lso_header_size,
816 __be32 mr_key,
817 struct mlx4_en_tx_info *tx_info)
818{
819 struct device *ddev = priv->ddev;
820 dma_addr_t dma = 0;
821 u32 byte_count = 0;
822 int i_frag;
823
824 /* Map fragments if any */
825 for (i_frag = shinfo->nr_frags - 1; i_frag >= 0; i_frag--) {
826 const skb_frag_t *frag = &shinfo->frags[i_frag];
827 byte_count = skb_frag_size(frag);
828 dma = skb_frag_dma_map(dev: ddev, frag,
829 offset: 0, size: byte_count,
830 dir: DMA_TO_DEVICE);
831 if (dma_mapping_error(dev: ddev, dma_addr: dma))
832 goto tx_drop_unmap;
833
834 data->addr = cpu_to_be64(dma);
835 data->lkey = mr_key;
836 dma_wmb();
837 data->byte_count = cpu_to_be32(byte_count);
838 --data;
839 }
840
841 /* Map linear part if needed */
842 if (tx_info->linear) {
843 byte_count = skb_headlen(skb) - lso_header_size;
844
845 dma = dma_map_single(ddev, skb->data +
846 lso_header_size, byte_count,
847 DMA_TO_DEVICE);
848 if (dma_mapping_error(dev: ddev, dma_addr: dma))
849 goto tx_drop_unmap;
850
851 data->addr = cpu_to_be64(dma);
852 data->lkey = mr_key;
853 dma_wmb();
854 data->byte_count = cpu_to_be32(byte_count);
855 }
856 /* tx completion can avoid cache line miss for common cases */
857 tx_info->map0_dma = dma;
858 tx_info->map0_byte_count = byte_count;
859
860 return true;
861
862tx_drop_unmap:
863 en_err(priv, "DMA mapping error\n");
864
865 while (++i_frag < shinfo->nr_frags) {
866 ++data;
867 dma_unmap_page(ddev, (dma_addr_t)be64_to_cpu(data->addr),
868 be32_to_cpu(data->byte_count),
869 DMA_TO_DEVICE);
870 }
871
872 return false;
873}
874
875netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
876{
877 struct skb_shared_info *shinfo = skb_shinfo(skb);
878 struct mlx4_en_priv *priv = netdev_priv(dev);
879 union mlx4_wqe_qpn_vlan qpn_vlan = {};
880 struct mlx4_en_tx_ring *ring;
881 struct mlx4_en_tx_desc *tx_desc;
882 struct mlx4_wqe_data_seg *data;
883 struct mlx4_en_tx_info *tx_info;
884 u32 __maybe_unused ring_cons;
885 int tx_ind;
886 int nr_txbb;
887 int desc_size;
888 int real_size;
889 u32 index, bf_index;
890 struct ipv6hdr *h6;
891 __be32 op_own;
892 int lso_header_size;
893 void *fragptr = NULL;
894 bool bounce = false;
895 bool send_doorbell;
896 bool stop_queue;
897 bool inline_ok;
898 u8 data_offset;
899 int hopbyhop;
900 bool bf_ok;
901
902 tx_ind = skb_get_queue_mapping(skb);
903 ring = priv->tx_ring[TX][tx_ind];
904
905 if (unlikely(!priv->port_up))
906 goto tx_drop;
907
908 real_size = get_real_size(skb, shinfo, dev, lso_header_size: &lso_header_size,
909 inline_ok: &inline_ok, pfrag: &fragptr, hopbyhop: &hopbyhop);
910 if (unlikely(!real_size))
911 goto tx_drop_count;
912
913 /* Align descriptor to TXBB size */
914 desc_size = ALIGN(real_size, TXBB_SIZE);
915 nr_txbb = desc_size >> LOG_TXBB_SIZE;
916
917 bf_ok = ring->bf_enabled;
918 if (skb_vlan_tag_present(skb)) {
919 u16 vlan_proto;
920
921 qpn_vlan.vlan_tag = cpu_to_be16(skb_vlan_tag_get(skb));
922 vlan_proto = be16_to_cpu(skb->vlan_proto);
923 if (vlan_proto == ETH_P_8021AD)
924 qpn_vlan.ins_vlan = MLX4_WQE_CTRL_INS_SVLAN;
925 else if (vlan_proto == ETH_P_8021Q)
926 qpn_vlan.ins_vlan = MLX4_WQE_CTRL_INS_CVLAN;
927 else
928 qpn_vlan.ins_vlan = 0;
929 bf_ok = false;
930 }
931
932 netdev_txq_bql_enqueue_prefetchw(dev_queue: ring->tx_queue);
933
934 /* Packet is good - grab an index and transmit it */
935 index = ring->prod & ring->size_mask;
936 bf_index = ring->prod;
937
938 /* See if we have enough space for whole descriptor TXBB for setting
939 * SW ownership on next descriptor; if not, use a bounce buffer. */
940 if (likely(index + nr_txbb <= ring->size))
941 tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
942 else {
943 if (unlikely(nr_txbb > MLX4_MAX_DESC_TXBBS)) {
944 if (netif_msg_tx_err(priv))
945 en_warn(priv, "Oversized header or SG list\n");
946 goto tx_drop_count;
947 }
948 tx_desc = (struct mlx4_en_tx_desc *) ring->bounce_buf;
949 bounce = true;
950 bf_ok = false;
951 }
952
953 /* Save skb in tx_info ring */
954 tx_info = &ring->tx_info[index];
955 tx_info->skb = skb;
956 tx_info->nr_txbb = nr_txbb;
957
958 if (!lso_header_size) {
959 data = &tx_desc->data;
960 data_offset = offsetof(struct mlx4_en_tx_desc, data);
961 } else {
962 int lso_align = ALIGN(lso_header_size - hopbyhop + 4, DS_SIZE);
963
964 data = (void *)&tx_desc->lso + lso_align;
965 data_offset = offsetof(struct mlx4_en_tx_desc, lso) + lso_align;
966 }
967
968 /* valid only for none inline segments */
969 tx_info->data_offset = data_offset;
970
971 tx_info->inl = inline_ok;
972
973 tx_info->linear = lso_header_size < skb_headlen(skb) && !inline_ok;
974
975 tx_info->nr_maps = shinfo->nr_frags + tx_info->linear;
976 data += tx_info->nr_maps - 1;
977
978 if (!tx_info->inl)
979 if (!mlx4_en_build_dma_wqe(priv, shinfo, data, skb,
980 lso_header_size, mr_key: ring->mr_key,
981 tx_info))
982 goto tx_drop_count;
983
984 /*
985 * For timestamping add flag to skb_shinfo and
986 * set flag for further reference
987 */
988 tx_info->ts_requested = 0;
989 if (unlikely(ring->hwtstamp_tx_type == HWTSTAMP_TX_ON &&
990 shinfo->tx_flags & SKBTX_HW_TSTAMP)) {
991 shinfo->tx_flags |= SKBTX_IN_PROGRESS;
992 tx_info->ts_requested = 1;
993 }
994
995 /* Prepare ctrl segement apart opcode+ownership, which depends on
996 * whether LSO is used */
997 tx_desc->ctrl.srcrb_flags = priv->ctrl_flags;
998 if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
999 if (!skb->encapsulation)
1000 tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM |
1001 MLX4_WQE_CTRL_TCP_UDP_CSUM);
1002 else
1003 tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM);
1004 ring->tx_csum++;
1005 }
1006
1007 if (priv->flags & MLX4_EN_FLAG_ENABLE_HW_LOOPBACK) {
1008 struct ethhdr *ethh;
1009
1010 /* Copy dst mac address to wqe. This allows loopback in eSwitch,
1011 * so that VFs and PF can communicate with each other
1012 */
1013 ethh = (struct ethhdr *)skb->data;
1014 tx_desc->ctrl.srcrb_flags16[0] = get_unaligned((__be16 *)ethh->h_dest);
1015 tx_desc->ctrl.imm = get_unaligned((__be32 *)(ethh->h_dest + 2));
1016 }
1017
1018 /* Handle LSO (TSO) packets */
1019 if (lso_header_size) {
1020 int i;
1021
1022 /* Mark opcode as LSO */
1023 op_own = cpu_to_be32(MLX4_OPCODE_LSO | (1 << 6)) |
1024 ((ring->prod & ring->size) ?
1025 cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1026
1027 lso_header_size -= hopbyhop;
1028 /* Fill in the LSO prefix */
1029 tx_desc->lso.mss_hdr_size = cpu_to_be32(
1030 shinfo->gso_size << 16 | lso_header_size);
1031
1032
1033 if (unlikely(hopbyhop)) {
1034 /* remove the HBH header.
1035 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
1036 */
1037 memcpy(tx_desc->lso.header, skb->data, ETH_HLEN + sizeof(*h6));
1038 h6 = (struct ipv6hdr *)((char *)tx_desc->lso.header + ETH_HLEN);
1039 h6->nexthdr = IPPROTO_TCP;
1040 /* Copy the TCP header after the IPv6 one */
1041 memcpy(h6 + 1,
1042 skb->data + ETH_HLEN + sizeof(*h6) +
1043 sizeof(struct hop_jumbo_hdr),
1044 tcp_hdrlen(skb));
1045 /* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
1046 } else {
1047 /* Copy headers;
1048 * note that we already verified that it is linear
1049 */
1050 memcpy(tx_desc->lso.header, skb->data, lso_header_size);
1051 }
1052 ring->tso_packets++;
1053
1054 i = shinfo->gso_segs;
1055 tx_info->nr_bytes = skb->len + (i - 1) * lso_header_size;
1056 ring->packets += i;
1057 } else {
1058 /* Normal (Non LSO) packet */
1059 op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
1060 ((ring->prod & ring->size) ?
1061 cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1062 tx_info->nr_bytes = max_t(unsigned int, skb->len, ETH_ZLEN);
1063 ring->packets++;
1064 }
1065 ring->bytes += tx_info->nr_bytes;
1066
1067 if (tx_info->inl)
1068 build_inline_wqe(tx_desc, skb, shinfo, fragptr);
1069
1070 if (skb->encapsulation) {
1071 union {
1072 struct iphdr *v4;
1073 struct ipv6hdr *v6;
1074 unsigned char *hdr;
1075 } ip;
1076 u8 proto;
1077
1078 ip.hdr = skb_inner_network_header(skb);
1079 proto = (ip.v4->version == 4) ? ip.v4->protocol :
1080 ip.v6->nexthdr;
1081
1082 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
1083 op_own |= cpu_to_be32(MLX4_WQE_CTRL_IIP | MLX4_WQE_CTRL_ILP);
1084 else
1085 op_own |= cpu_to_be32(MLX4_WQE_CTRL_IIP);
1086 }
1087
1088 WRITE_ONCE(ring->prod, ring->prod + nr_txbb);
1089
1090 /* If we used a bounce buffer then copy descriptor back into place */
1091 if (unlikely(bounce))
1092 tx_desc = mlx4_en_bounce_to_desc(priv, ring, index, desc_size);
1093
1094 skb_tx_timestamp(skb);
1095
1096 /* Check available TXBBs And 2K spare for prefetch */
1097 stop_queue = mlx4_en_is_tx_ring_full(ring);
1098 if (unlikely(stop_queue)) {
1099 netif_tx_stop_queue(dev_queue: ring->tx_queue);
1100 ring->queue_stopped++;
1101 }
1102
1103 send_doorbell = __netdev_tx_sent_queue(dev_queue: ring->tx_queue,
1104 bytes: tx_info->nr_bytes,
1105 xmit_more: netdev_xmit_more());
1106
1107 real_size = (real_size / 16) & 0x3f;
1108
1109 bf_ok &= desc_size <= MAX_BF && send_doorbell;
1110
1111 if (bf_ok)
1112 qpn_vlan.bf_qpn = ring->doorbell_qpn | cpu_to_be32(real_size);
1113 else
1114 qpn_vlan.fence_size = real_size;
1115
1116 mlx4_en_tx_write_desc(ring, tx_desc, qpn_vlan, desc_size, bf_index,
1117 op_own, bf_ok, send_doorbell);
1118
1119 if (unlikely(stop_queue)) {
1120 /* If queue was emptied after the if (stop_queue) , and before
1121 * the netif_tx_stop_queue() - need to wake the queue,
1122 * or else it will remain stopped forever.
1123 * Need a memory barrier to make sure ring->cons was not
1124 * updated before queue was stopped.
1125 */
1126 smp_rmb();
1127
1128 if (unlikely(!mlx4_en_is_tx_ring_full(ring))) {
1129 netif_tx_wake_queue(dev_queue: ring->tx_queue);
1130 ring->wake_queue++;
1131 }
1132 }
1133 return NETDEV_TX_OK;
1134
1135tx_drop_count:
1136 ring->tx_dropped++;
1137tx_drop:
1138 dev_kfree_skb_any(skb);
1139 return NETDEV_TX_OK;
1140}
1141
1142#define MLX4_EN_XDP_TX_NRTXBB 1
1143#define MLX4_EN_XDP_TX_REAL_SZ (((CTRL_SIZE + MLX4_EN_XDP_TX_NRTXBB * DS_SIZE) \
1144 / 16) & 0x3f)
1145
1146void mlx4_en_init_tx_xdp_ring_descs(struct mlx4_en_priv *priv,
1147 struct mlx4_en_tx_ring *ring)
1148{
1149 int i;
1150
1151 for (i = 0; i < ring->size; i++) {
1152 struct mlx4_en_tx_info *tx_info = &ring->tx_info[i];
1153 struct mlx4_en_tx_desc *tx_desc = ring->buf +
1154 (i << LOG_TXBB_SIZE);
1155
1156 tx_info->map0_byte_count = PAGE_SIZE;
1157 tx_info->nr_txbb = MLX4_EN_XDP_TX_NRTXBB;
1158 tx_info->data_offset = offsetof(struct mlx4_en_tx_desc, data);
1159 tx_info->ts_requested = 0;
1160 tx_info->nr_maps = 1;
1161 tx_info->linear = 1;
1162 tx_info->inl = 0;
1163
1164 tx_desc->data.lkey = ring->mr_key;
1165 tx_desc->ctrl.qpn_vlan.fence_size = MLX4_EN_XDP_TX_REAL_SZ;
1166 tx_desc->ctrl.srcrb_flags = priv->ctrl_flags;
1167 }
1168}
1169
1170netdev_tx_t mlx4_en_xmit_frame(struct mlx4_en_rx_ring *rx_ring,
1171 struct mlx4_en_rx_alloc *frame,
1172 struct mlx4_en_priv *priv, unsigned int length,
1173 int tx_ind, bool *doorbell_pending)
1174{
1175 struct mlx4_en_tx_desc *tx_desc;
1176 struct mlx4_en_tx_info *tx_info;
1177 struct mlx4_wqe_data_seg *data;
1178 struct mlx4_en_tx_ring *ring;
1179 dma_addr_t dma;
1180 __be32 op_own;
1181 int index;
1182
1183 if (unlikely(!priv->port_up))
1184 goto tx_drop;
1185
1186 ring = priv->tx_ring[TX_XDP][tx_ind];
1187
1188 if (unlikely(mlx4_en_is_tx_ring_full(ring)))
1189 goto tx_drop_count;
1190
1191 index = ring->prod & ring->size_mask;
1192 tx_info = &ring->tx_info[index];
1193
1194 tx_desc = ring->buf + (index << LOG_TXBB_SIZE);
1195 data = &tx_desc->data;
1196
1197 dma = frame->dma;
1198
1199 tx_info->page = frame->page;
1200 frame->page = NULL;
1201 tx_info->map0_dma = dma;
1202 tx_info->nr_bytes = max_t(unsigned int, length, ETH_ZLEN);
1203
1204 dma_sync_single_range_for_device(dev: priv->ddev, addr: dma, offset: frame->page_offset,
1205 size: length, dir: DMA_TO_DEVICE);
1206
1207 data->addr = cpu_to_be64(dma + frame->page_offset);
1208 dma_wmb();
1209 data->byte_count = cpu_to_be32(length);
1210
1211 /* tx completion can avoid cache line miss for common cases */
1212
1213 op_own = cpu_to_be32(MLX4_OPCODE_SEND) |
1214 ((ring->prod & ring->size) ?
1215 cpu_to_be32(MLX4_EN_BIT_DESC_OWN) : 0);
1216
1217 rx_ring->xdp_tx++;
1218
1219 WRITE_ONCE(ring->prod, ring->prod + MLX4_EN_XDP_TX_NRTXBB);
1220
1221 /* Ensure new descriptor hits memory
1222 * before setting ownership of this descriptor to HW
1223 */
1224 dma_wmb();
1225 tx_desc->ctrl.owner_opcode = op_own;
1226 ring->xmit_more++;
1227
1228 *doorbell_pending = true;
1229
1230 return NETDEV_TX_OK;
1231
1232tx_drop_count:
1233 rx_ring->xdp_tx_full++;
1234 *doorbell_pending = true;
1235tx_drop:
1236 return NETDEV_TX_BUSY;
1237}
1238

source code of linux/drivers/net/ethernet/mellanox/mlx4/en_tx.c