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(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(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(&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	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(cpumask_local_spread(queue_index,
142						     priv->mdev->dev->numa_node),
143				&ring->sp_affinity_mask);
144
145	*pring = ring;
146	return 0;
147
148err_reserve:
149	mlx4_qp_release_range(mdev->dev, ring->qpn, 1);
150err_hwq_res:
151	mlx4_free_hwq_res(mdev->dev, &ring->sp_wqres, ring->buf_size);
152err_bounce:
153	kfree(ring->bounce_buf);
154	ring->bounce_buf = NULL;
155err_info:
156	kvfree(ring->tx_info);
157	ring->tx_info = NULL;
158err_ring:
159	kfree(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(mdev->dev, &ring->bf);
173	mlx4_qp_remove(mdev->dev, &ring->sp_qp);
174	mlx4_qp_free(mdev->dev, &ring->sp_qp);
175	mlx4_qp_release_range(priv->mdev->dev, ring->qpn, 1);
176	mlx4_free_hwq_res(mdev->dev, &ring->sp_wqres, ring->buf_size);
177	kfree(ring->bounce_buf);
178	ring->bounce_buf = NULL;
179	kvfree(ring->tx_info);
180	ring->tx_info = NULL;
181	kfree(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, ring->size, ring->sp_stride, 1, 0, ring->qpn,
205				ring->sp_cqn, user_prio, &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(mdev->dev, &ring->sp_wqres.mtt, &ring->sp_context,
212			       &ring->sp_qp, &ring->sp_qp_state);
213	if (!cpumask_empty(&ring->sp_affinity_mask))
214		netif_set_xps_queue(priv->dev, &ring->sp_affinity_mask,
215				    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(mdev->dev, NULL, ring->sp_qp_state,
226		       MLX4_QP_STATE_RST, NULL, 0, 0, &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(&skb->users);
292
293	if (unlikely(timestamp)) {
294		struct skb_shared_hwtstamps hwts;
295
296		mlx4_en_fill_hwtstamps(priv->mdev, &hwts, timestamp);
297		skb_tstamp_tx(skb, &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, 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->recycle_ring, &frame)) {
359		dma_unmap_page(priv->ddev, tx_info->map0_dma,
360			       PAGE_SIZE, priv->dma_dir);
361		put_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(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, "", DUMP_PREFIX_OFFSET, 16, 1, err_cqe, sizeof(*err_cqe),
412		       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, "", DUMP_PREFIX_OFFSET, 16, 1, tx_desc, desc_size, false);
421
422	if (test_and_set_bit(MLX4_EN_STATE_FLAG_RESTARTING, &priv->state))
423		return;
424
425	en_err(priv, "Scheduling port restart\n");
426	queue_work(mdev->workqueue, &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(ring->tx_queue);
455
456	index = cons_index & size_mask;
457	cqe = mlx4_en_get_cqe(buf, index, 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(MLX4_EN_TX_RING_STATE_RECOVERING, &ring->state))
477				mlx4_en_handle_err_cqe(priv, (struct mlx4_err_cqe *)cqe, 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, stamp_index,
500					  !!((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, index, 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(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(ring->tx_queue, packets, bytes);
529
530	/* Wakeup Tx queue if this stopped, and ring is not full.
531	 */
532	if (netif_tx_queue_stopped(ring->tx_queue) &&
533	    !mlx4_en_is_tx_ring_full(ring)) {
534		netif_tx_wake_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(cq->dev);
545
546	if (likely(priv->port_up))
547		napi_schedule_irqoff(&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, budget);
561	if (work_done >= budget)
562		return budget;
563
564	if (napi_complete_done(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(&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(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, 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, 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, spc);
725			inl = (void *)inl->data + spc;
726			skb_copy_from_linear_data_offset(skb, spc, inl->data,
727							 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(dst, src, 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(ring->bf.reg + ring->bf.offset, &tx_desc->ctrl,
793			     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(ddev, frag,
829				       0, byte_count,
830				       DMA_TO_DEVICE);
831		if (dma_mapping_error(ddev, 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(ddev, 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,
909				  &inline_ok, &fragptr, &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(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, 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(ring->tx_queue);
1100		ring->queue_stopped++;
1101	}
1102
1103	send_doorbell = __netdev_tx_sent_queue(ring->tx_queue,
1104					       tx_info->nr_bytes,
1105					       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(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(priv->ddev, dma, frame->page_offset,
1205					 length, 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