xref: /openbmc/linux/drivers/net/ethernet/mellanox/mlx4/en_rx.c (revision c51d39010a1bccc9c1294e2d7c00005aefeb2b5c)
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 <net/busy_poll.h>
35 #include <linux/bpf.h>
36 #include <linux/mlx4/cq.h>
37 #include <linux/slab.h>
38 #include <linux/mlx4/qp.h>
39 #include <linux/skbuff.h>
40 #include <linux/rculist.h>
41 #include <linux/if_ether.h>
42 #include <linux/if_vlan.h>
43 #include <linux/vmalloc.h>
44 #include <linux/irq.h>
45 
46 #if IS_ENABLED(CONFIG_IPV6)
47 #include <net/ip6_checksum.h>
48 #endif
49 
50 #include "mlx4_en.h"
51 
52 static int mlx4_alloc_pages(struct mlx4_en_priv *priv,
53 			    struct mlx4_en_rx_alloc *page_alloc,
54 			    const struct mlx4_en_frag_info *frag_info,
55 			    gfp_t _gfp)
56 {
57 	int order;
58 	struct page *page;
59 	dma_addr_t dma;
60 
61 	for (order = frag_info->order; ;) {
62 		gfp_t gfp = _gfp;
63 
64 		if (order)
65 			gfp |= __GFP_COMP | __GFP_NOWARN | __GFP_NOMEMALLOC;
66 		page = alloc_pages(gfp, order);
67 		if (likely(page))
68 			break;
69 		if (--order < 0 ||
70 		    ((PAGE_SIZE << order) < frag_info->frag_size))
71 			return -ENOMEM;
72 	}
73 	dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE << order,
74 			   frag_info->dma_dir);
75 	if (unlikely(dma_mapping_error(priv->ddev, dma))) {
76 		put_page(page);
77 		return -ENOMEM;
78 	}
79 	page_alloc->page_size = PAGE_SIZE << order;
80 	page_alloc->page = page;
81 	page_alloc->dma = dma;
82 	page_alloc->page_offset = 0;
83 	/* Not doing get_page() for each frag is a big win
84 	 * on asymetric workloads. Note we can not use atomic_set().
85 	 */
86 	page_ref_add(page, page_alloc->page_size / frag_info->frag_stride - 1);
87 	return 0;
88 }
89 
90 static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv,
91 			       struct mlx4_en_rx_desc *rx_desc,
92 			       struct mlx4_en_rx_alloc *frags,
93 			       struct mlx4_en_rx_alloc *ring_alloc,
94 			       gfp_t gfp)
95 {
96 	struct mlx4_en_rx_alloc page_alloc[MLX4_EN_MAX_RX_FRAGS];
97 	const struct mlx4_en_frag_info *frag_info;
98 	struct page *page;
99 	dma_addr_t dma;
100 	int i;
101 
102 	for (i = 0; i < priv->num_frags; i++) {
103 		frag_info = &priv->frag_info[i];
104 		page_alloc[i] = ring_alloc[i];
105 		page_alloc[i].page_offset += frag_info->frag_stride;
106 
107 		if (page_alloc[i].page_offset + frag_info->frag_stride <=
108 		    ring_alloc[i].page_size)
109 			continue;
110 
111 		if (unlikely(mlx4_alloc_pages(priv, &page_alloc[i],
112 					      frag_info, gfp)))
113 			goto out;
114 	}
115 
116 	for (i = 0; i < priv->num_frags; i++) {
117 		frags[i] = ring_alloc[i];
118 		dma = ring_alloc[i].dma + ring_alloc[i].page_offset;
119 		ring_alloc[i] = page_alloc[i];
120 		rx_desc->data[i].addr = cpu_to_be64(dma);
121 	}
122 
123 	return 0;
124 
125 out:
126 	while (i--) {
127 		if (page_alloc[i].page != ring_alloc[i].page) {
128 			dma_unmap_page(priv->ddev, page_alloc[i].dma,
129 				page_alloc[i].page_size,
130 				priv->frag_info[i].dma_dir);
131 			page = page_alloc[i].page;
132 			/* Revert changes done by mlx4_alloc_pages */
133 			page_ref_sub(page, page_alloc[i].page_size /
134 					   priv->frag_info[i].frag_stride - 1);
135 			put_page(page);
136 		}
137 	}
138 	return -ENOMEM;
139 }
140 
141 static void mlx4_en_free_frag(struct mlx4_en_priv *priv,
142 			      struct mlx4_en_rx_alloc *frags,
143 			      int i)
144 {
145 	const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
146 	u32 next_frag_end = frags[i].page_offset + 2 * frag_info->frag_stride;
147 
148 
149 	if (next_frag_end > frags[i].page_size)
150 		dma_unmap_page(priv->ddev, frags[i].dma, frags[i].page_size,
151 			       frag_info->dma_dir);
152 
153 	if (frags[i].page)
154 		put_page(frags[i].page);
155 }
156 
157 static int mlx4_en_init_allocator(struct mlx4_en_priv *priv,
158 				  struct mlx4_en_rx_ring *ring)
159 {
160 	int i;
161 	struct mlx4_en_rx_alloc *page_alloc;
162 
163 	for (i = 0; i < priv->num_frags; i++) {
164 		const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
165 
166 		if (mlx4_alloc_pages(priv, &ring->page_alloc[i],
167 				     frag_info, GFP_KERNEL | __GFP_COLD))
168 			goto out;
169 
170 		en_dbg(DRV, priv, "  frag %d allocator: - size:%d frags:%d\n",
171 		       i, ring->page_alloc[i].page_size,
172 		       page_ref_count(ring->page_alloc[i].page));
173 	}
174 	return 0;
175 
176 out:
177 	while (i--) {
178 		struct page *page;
179 
180 		page_alloc = &ring->page_alloc[i];
181 		dma_unmap_page(priv->ddev, page_alloc->dma,
182 			       page_alloc->page_size,
183 			       priv->frag_info[i].dma_dir);
184 		page = page_alloc->page;
185 		/* Revert changes done by mlx4_alloc_pages */
186 		page_ref_sub(page, page_alloc->page_size /
187 				   priv->frag_info[i].frag_stride - 1);
188 		put_page(page);
189 		page_alloc->page = NULL;
190 	}
191 	return -ENOMEM;
192 }
193 
194 static void mlx4_en_destroy_allocator(struct mlx4_en_priv *priv,
195 				      struct mlx4_en_rx_ring *ring)
196 {
197 	struct mlx4_en_rx_alloc *page_alloc;
198 	int i;
199 
200 	for (i = 0; i < priv->num_frags; i++) {
201 		const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
202 
203 		page_alloc = &ring->page_alloc[i];
204 		en_dbg(DRV, priv, "Freeing allocator:%d count:%d\n",
205 		       i, page_count(page_alloc->page));
206 
207 		dma_unmap_page(priv->ddev, page_alloc->dma,
208 				page_alloc->page_size, frag_info->dma_dir);
209 		while (page_alloc->page_offset + frag_info->frag_stride <
210 		       page_alloc->page_size) {
211 			put_page(page_alloc->page);
212 			page_alloc->page_offset += frag_info->frag_stride;
213 		}
214 		page_alloc->page = NULL;
215 	}
216 }
217 
218 static void mlx4_en_init_rx_desc(struct mlx4_en_priv *priv,
219 				 struct mlx4_en_rx_ring *ring, int index)
220 {
221 	struct mlx4_en_rx_desc *rx_desc = ring->buf + ring->stride * index;
222 	int possible_frags;
223 	int i;
224 
225 	/* Set size and memtype fields */
226 	for (i = 0; i < priv->num_frags; i++) {
227 		rx_desc->data[i].byte_count =
228 			cpu_to_be32(priv->frag_info[i].frag_size);
229 		rx_desc->data[i].lkey = cpu_to_be32(priv->mdev->mr.key);
230 	}
231 
232 	/* If the number of used fragments does not fill up the ring stride,
233 	 * remaining (unused) fragments must be padded with null address/size
234 	 * and a special memory key */
235 	possible_frags = (ring->stride - sizeof(struct mlx4_en_rx_desc)) / DS_SIZE;
236 	for (i = priv->num_frags; i < possible_frags; i++) {
237 		rx_desc->data[i].byte_count = 0;
238 		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
239 		rx_desc->data[i].addr = 0;
240 	}
241 }
242 
243 static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
244 				   struct mlx4_en_rx_ring *ring, int index,
245 				   gfp_t gfp)
246 {
247 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index * ring->stride);
248 	struct mlx4_en_rx_alloc *frags = ring->rx_info +
249 					(index << priv->log_rx_info);
250 
251 	if (ring->page_cache.index > 0) {
252 		frags[0] = ring->page_cache.buf[--ring->page_cache.index];
253 		rx_desc->data[0].addr = cpu_to_be64(frags[0].dma);
254 		return 0;
255 	}
256 
257 	return mlx4_en_alloc_frags(priv, rx_desc, frags, ring->page_alloc, gfp);
258 }
259 
260 static inline bool mlx4_en_is_ring_empty(struct mlx4_en_rx_ring *ring)
261 {
262 	return ring->prod == ring->cons;
263 }
264 
265 static inline void mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
266 {
267 	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
268 }
269 
270 static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv,
271 				 struct mlx4_en_rx_ring *ring,
272 				 int index)
273 {
274 	struct mlx4_en_rx_alloc *frags;
275 	int nr;
276 
277 	frags = ring->rx_info + (index << priv->log_rx_info);
278 	for (nr = 0; nr < priv->num_frags; nr++) {
279 		en_dbg(DRV, priv, "Freeing fragment:%d\n", nr);
280 		mlx4_en_free_frag(priv, frags, nr);
281 	}
282 }
283 
284 static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
285 {
286 	struct mlx4_en_rx_ring *ring;
287 	int ring_ind;
288 	int buf_ind;
289 	int new_size;
290 
291 	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
292 		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
293 			ring = priv->rx_ring[ring_ind];
294 
295 			if (mlx4_en_prepare_rx_desc(priv, ring,
296 						    ring->actual_size,
297 						    GFP_KERNEL | __GFP_COLD)) {
298 				if (ring->actual_size < MLX4_EN_MIN_RX_SIZE) {
299 					en_err(priv, "Failed to allocate enough rx buffers\n");
300 					return -ENOMEM;
301 				} else {
302 					new_size = rounddown_pow_of_two(ring->actual_size);
303 					en_warn(priv, "Only %d buffers allocated reducing ring size to %d\n",
304 						ring->actual_size, new_size);
305 					goto reduce_rings;
306 				}
307 			}
308 			ring->actual_size++;
309 			ring->prod++;
310 		}
311 	}
312 	return 0;
313 
314 reduce_rings:
315 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
316 		ring = priv->rx_ring[ring_ind];
317 		while (ring->actual_size > new_size) {
318 			ring->actual_size--;
319 			ring->prod--;
320 			mlx4_en_free_rx_desc(priv, ring, ring->actual_size);
321 		}
322 	}
323 
324 	return 0;
325 }
326 
327 static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
328 				struct mlx4_en_rx_ring *ring)
329 {
330 	int index;
331 
332 	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
333 	       ring->cons, ring->prod);
334 
335 	/* Unmap and free Rx buffers */
336 	while (!mlx4_en_is_ring_empty(ring)) {
337 		index = ring->cons & ring->size_mask;
338 		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
339 		mlx4_en_free_rx_desc(priv, ring, index);
340 		++ring->cons;
341 	}
342 }
343 
344 void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev)
345 {
346 	int i;
347 	int num_of_eqs;
348 	int num_rx_rings;
349 	struct mlx4_dev *dev = mdev->dev;
350 
351 	mlx4_foreach_port(i, dev, MLX4_PORT_TYPE_ETH) {
352 		num_of_eqs = max_t(int, MIN_RX_RINGS,
353 				   min_t(int,
354 					 mlx4_get_eqs_per_port(mdev->dev, i),
355 					 DEF_RX_RINGS));
356 
357 		num_rx_rings = mlx4_low_memory_profile() ? MIN_RX_RINGS :
358 			min_t(int, num_of_eqs,
359 			      netif_get_num_default_rss_queues());
360 		mdev->profile.prof[i].rx_ring_num =
361 			rounddown_pow_of_two(num_rx_rings);
362 	}
363 }
364 
365 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
366 			   struct mlx4_en_rx_ring **pring,
367 			   u32 size, u16 stride, int node)
368 {
369 	struct mlx4_en_dev *mdev = priv->mdev;
370 	struct mlx4_en_rx_ring *ring;
371 	int err = -ENOMEM;
372 	int tmp;
373 
374 	ring = kzalloc_node(sizeof(*ring), GFP_KERNEL, node);
375 	if (!ring) {
376 		ring = kzalloc(sizeof(*ring), GFP_KERNEL);
377 		if (!ring) {
378 			en_err(priv, "Failed to allocate RX ring structure\n");
379 			return -ENOMEM;
380 		}
381 	}
382 
383 	ring->prod = 0;
384 	ring->cons = 0;
385 	ring->size = size;
386 	ring->size_mask = size - 1;
387 	ring->stride = stride;
388 	ring->log_stride = ffs(ring->stride) - 1;
389 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
390 
391 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
392 					sizeof(struct mlx4_en_rx_alloc));
393 	ring->rx_info = vmalloc_node(tmp, node);
394 	if (!ring->rx_info) {
395 		ring->rx_info = vmalloc(tmp);
396 		if (!ring->rx_info) {
397 			err = -ENOMEM;
398 			goto err_ring;
399 		}
400 	}
401 
402 	en_dbg(DRV, priv, "Allocated rx_info ring at addr:%p size:%d\n",
403 		 ring->rx_info, tmp);
404 
405 	/* Allocate HW buffers on provided NUMA node */
406 	set_dev_node(&mdev->dev->persist->pdev->dev, node);
407 	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
408 	set_dev_node(&mdev->dev->persist->pdev->dev, mdev->dev->numa_node);
409 	if (err)
410 		goto err_info;
411 
412 	ring->buf = ring->wqres.buf.direct.buf;
413 
414 	ring->hwtstamp_rx_filter = priv->hwtstamp_config.rx_filter;
415 
416 	*pring = ring;
417 	return 0;
418 
419 err_info:
420 	vfree(ring->rx_info);
421 	ring->rx_info = NULL;
422 err_ring:
423 	kfree(ring);
424 	*pring = NULL;
425 
426 	return err;
427 }
428 
429 int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
430 {
431 	struct mlx4_en_rx_ring *ring;
432 	int i;
433 	int ring_ind;
434 	int err;
435 	int stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
436 					DS_SIZE * priv->num_frags);
437 
438 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
439 		ring = priv->rx_ring[ring_ind];
440 
441 		ring->prod = 0;
442 		ring->cons = 0;
443 		ring->actual_size = 0;
444 		ring->cqn = priv->rx_cq[ring_ind]->mcq.cqn;
445 
446 		ring->stride = stride;
447 		if (ring->stride <= TXBB_SIZE)
448 			ring->buf += TXBB_SIZE;
449 
450 		ring->log_stride = ffs(ring->stride) - 1;
451 		ring->buf_size = ring->size * ring->stride;
452 
453 		memset(ring->buf, 0, ring->buf_size);
454 		mlx4_en_update_rx_prod_db(ring);
455 
456 		/* Initialize all descriptors */
457 		for (i = 0; i < ring->size; i++)
458 			mlx4_en_init_rx_desc(priv, ring, i);
459 
460 		/* Initialize page allocators */
461 		err = mlx4_en_init_allocator(priv, ring);
462 		if (err) {
463 			en_err(priv, "Failed initializing ring allocator\n");
464 			if (ring->stride <= TXBB_SIZE)
465 				ring->buf -= TXBB_SIZE;
466 			ring_ind--;
467 			goto err_allocator;
468 		}
469 	}
470 	err = mlx4_en_fill_rx_buffers(priv);
471 	if (err)
472 		goto err_buffers;
473 
474 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
475 		ring = priv->rx_ring[ring_ind];
476 
477 		ring->size_mask = ring->actual_size - 1;
478 		mlx4_en_update_rx_prod_db(ring);
479 	}
480 
481 	return 0;
482 
483 err_buffers:
484 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
485 		mlx4_en_free_rx_buf(priv, priv->rx_ring[ring_ind]);
486 
487 	ring_ind = priv->rx_ring_num - 1;
488 err_allocator:
489 	while (ring_ind >= 0) {
490 		if (priv->rx_ring[ring_ind]->stride <= TXBB_SIZE)
491 			priv->rx_ring[ring_ind]->buf -= TXBB_SIZE;
492 		mlx4_en_destroy_allocator(priv, priv->rx_ring[ring_ind]);
493 		ring_ind--;
494 	}
495 	return err;
496 }
497 
498 /* We recover from out of memory by scheduling our napi poll
499  * function (mlx4_en_process_cq), which tries to allocate
500  * all missing RX buffers (call to mlx4_en_refill_rx_buffers).
501  */
502 void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv)
503 {
504 	int ring;
505 
506 	if (!priv->port_up)
507 		return;
508 
509 	for (ring = 0; ring < priv->rx_ring_num; ring++) {
510 		if (mlx4_en_is_ring_empty(priv->rx_ring[ring]))
511 			napi_reschedule(&priv->rx_cq[ring]->napi);
512 	}
513 }
514 
515 /* When the rx ring is running in page-per-packet mode, a released frame can go
516  * directly into a small cache, to avoid unmapping or touching the page
517  * allocator. In bpf prog performance scenarios, buffers are either forwarded
518  * or dropped, never converted to skbs, so every page can come directly from
519  * this cache when it is sized to be a multiple of the napi budget.
520  */
521 bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
522 			struct mlx4_en_rx_alloc *frame)
523 {
524 	struct mlx4_en_page_cache *cache = &ring->page_cache;
525 
526 	if (cache->index >= MLX4_EN_CACHE_SIZE)
527 		return false;
528 
529 	cache->buf[cache->index++] = *frame;
530 	return true;
531 }
532 
533 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
534 			     struct mlx4_en_rx_ring **pring,
535 			     u32 size, u16 stride)
536 {
537 	struct mlx4_en_dev *mdev = priv->mdev;
538 	struct mlx4_en_rx_ring *ring = *pring;
539 	struct bpf_prog *old_prog;
540 
541 	old_prog = rcu_dereference_protected(
542 					ring->xdp_prog,
543 					lockdep_is_held(&mdev->state_lock));
544 	if (old_prog)
545 		bpf_prog_put(old_prog);
546 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
547 	vfree(ring->rx_info);
548 	ring->rx_info = NULL;
549 	kfree(ring);
550 	*pring = NULL;
551 }
552 
553 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
554 				struct mlx4_en_rx_ring *ring)
555 {
556 	int i;
557 
558 	for (i = 0; i < ring->page_cache.index; i++) {
559 		struct mlx4_en_rx_alloc *frame = &ring->page_cache.buf[i];
560 
561 		dma_unmap_page(priv->ddev, frame->dma, frame->page_size,
562 			       priv->frag_info[0].dma_dir);
563 		put_page(frame->page);
564 	}
565 	ring->page_cache.index = 0;
566 	mlx4_en_free_rx_buf(priv, ring);
567 	if (ring->stride <= TXBB_SIZE)
568 		ring->buf -= TXBB_SIZE;
569 	mlx4_en_destroy_allocator(priv, ring);
570 }
571 
572 
573 static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
574 				    struct mlx4_en_rx_desc *rx_desc,
575 				    struct mlx4_en_rx_alloc *frags,
576 				    struct sk_buff *skb,
577 				    int length)
578 {
579 	struct skb_frag_struct *skb_frags_rx = skb_shinfo(skb)->frags;
580 	struct mlx4_en_frag_info *frag_info;
581 	int nr;
582 	dma_addr_t dma;
583 
584 	/* Collect used fragments while replacing them in the HW descriptors */
585 	for (nr = 0; nr < priv->num_frags; nr++) {
586 		frag_info = &priv->frag_info[nr];
587 		if (length <= frag_info->frag_prefix_size)
588 			break;
589 		if (unlikely(!frags[nr].page))
590 			goto fail;
591 
592 		dma = be64_to_cpu(rx_desc->data[nr].addr);
593 		dma_sync_single_for_cpu(priv->ddev, dma, frag_info->frag_size,
594 					DMA_FROM_DEVICE);
595 
596 		/* Save page reference in skb */
597 		__skb_frag_set_page(&skb_frags_rx[nr], frags[nr].page);
598 		skb_frag_size_set(&skb_frags_rx[nr], frag_info->frag_size);
599 		skb_frags_rx[nr].page_offset = frags[nr].page_offset;
600 		skb->truesize += frag_info->frag_stride;
601 		frags[nr].page = NULL;
602 	}
603 	/* Adjust size of last fragment to match actual length */
604 	if (nr > 0)
605 		skb_frag_size_set(&skb_frags_rx[nr - 1],
606 			length - priv->frag_info[nr - 1].frag_prefix_size);
607 	return nr;
608 
609 fail:
610 	while (nr > 0) {
611 		nr--;
612 		__skb_frag_unref(&skb_frags_rx[nr]);
613 	}
614 	return 0;
615 }
616 
617 
618 static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv,
619 				      struct mlx4_en_rx_desc *rx_desc,
620 				      struct mlx4_en_rx_alloc *frags,
621 				      unsigned int length)
622 {
623 	struct sk_buff *skb;
624 	void *va;
625 	int used_frags;
626 	dma_addr_t dma;
627 
628 	skb = netdev_alloc_skb(priv->dev, SMALL_PACKET_SIZE + NET_IP_ALIGN);
629 	if (unlikely(!skb)) {
630 		en_dbg(RX_ERR, priv, "Failed allocating skb\n");
631 		return NULL;
632 	}
633 	skb_reserve(skb, NET_IP_ALIGN);
634 	skb->len = length;
635 
636 	/* Get pointer to first fragment so we could copy the headers into the
637 	 * (linear part of the) skb */
638 	va = page_address(frags[0].page) + frags[0].page_offset;
639 
640 	if (length <= SMALL_PACKET_SIZE) {
641 		/* We are copying all relevant data to the skb - temporarily
642 		 * sync buffers for the copy */
643 		dma = be64_to_cpu(rx_desc->data[0].addr);
644 		dma_sync_single_for_cpu(priv->ddev, dma, length,
645 					DMA_FROM_DEVICE);
646 		skb_copy_to_linear_data(skb, va, length);
647 		skb->tail += length;
648 	} else {
649 		unsigned int pull_len;
650 
651 		/* Move relevant fragments to skb */
652 		used_frags = mlx4_en_complete_rx_desc(priv, rx_desc, frags,
653 							skb, length);
654 		if (unlikely(!used_frags)) {
655 			kfree_skb(skb);
656 			return NULL;
657 		}
658 		skb_shinfo(skb)->nr_frags = used_frags;
659 
660 		pull_len = eth_get_headlen(va, SMALL_PACKET_SIZE);
661 		/* Copy headers into the skb linear buffer */
662 		memcpy(skb->data, va, pull_len);
663 		skb->tail += pull_len;
664 
665 		/* Skip headers in first fragment */
666 		skb_shinfo(skb)->frags[0].page_offset += pull_len;
667 
668 		/* Adjust size of first fragment */
669 		skb_frag_size_sub(&skb_shinfo(skb)->frags[0], pull_len);
670 		skb->data_len = length - pull_len;
671 	}
672 	return skb;
673 }
674 
675 static void validate_loopback(struct mlx4_en_priv *priv, struct sk_buff *skb)
676 {
677 	int i;
678 	int offset = ETH_HLEN;
679 
680 	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++, offset++) {
681 		if (*(skb->data + offset) != (unsigned char) (i & 0xff))
682 			goto out_loopback;
683 	}
684 	/* Loopback found */
685 	priv->loopback_ok = 1;
686 
687 out_loopback:
688 	dev_kfree_skb_any(skb);
689 }
690 
691 static bool mlx4_en_refill_rx_buffers(struct mlx4_en_priv *priv,
692 				      struct mlx4_en_rx_ring *ring)
693 {
694 	u32 missing = ring->actual_size - (ring->prod - ring->cons);
695 
696 	/* Try to batch allocations, but not too much. */
697 	if (missing < 8)
698 		return false;
699 	do {
700 		if (mlx4_en_prepare_rx_desc(priv, ring,
701 					    ring->prod & ring->size_mask,
702 					    GFP_ATOMIC | __GFP_COLD))
703 			break;
704 		ring->prod++;
705 	} while (--missing);
706 
707 	return true;
708 }
709 
710 /* When hardware doesn't strip the vlan, we need to calculate the checksum
711  * over it and add it to the hardware's checksum calculation
712  */
713 static inline __wsum get_fixed_vlan_csum(__wsum hw_checksum,
714 					 struct vlan_hdr *vlanh)
715 {
716 	return csum_add(hw_checksum, *(__wsum *)vlanh);
717 }
718 
719 /* Although the stack expects checksum which doesn't include the pseudo
720  * header, the HW adds it. To address that, we are subtracting the pseudo
721  * header checksum from the checksum value provided by the HW.
722  */
723 static void get_fixed_ipv4_csum(__wsum hw_checksum, struct sk_buff *skb,
724 				struct iphdr *iph)
725 {
726 	__u16 length_for_csum = 0;
727 	__wsum csum_pseudo_header = 0;
728 
729 	length_for_csum = (be16_to_cpu(iph->tot_len) - (iph->ihl << 2));
730 	csum_pseudo_header = csum_tcpudp_nofold(iph->saddr, iph->daddr,
731 						length_for_csum, iph->protocol, 0);
732 	skb->csum = csum_sub(hw_checksum, csum_pseudo_header);
733 }
734 
735 #if IS_ENABLED(CONFIG_IPV6)
736 /* In IPv6 packets, besides subtracting the pseudo header checksum,
737  * we also compute/add the IP header checksum which
738  * is not added by the HW.
739  */
740 static int get_fixed_ipv6_csum(__wsum hw_checksum, struct sk_buff *skb,
741 			       struct ipv6hdr *ipv6h)
742 {
743 	__wsum csum_pseudo_hdr = 0;
744 
745 	if (unlikely(ipv6h->nexthdr == IPPROTO_FRAGMENT ||
746 		     ipv6h->nexthdr == IPPROTO_HOPOPTS))
747 		return -1;
748 	hw_checksum = csum_add(hw_checksum, (__force __wsum)htons(ipv6h->nexthdr));
749 
750 	csum_pseudo_hdr = csum_partial(&ipv6h->saddr,
751 				       sizeof(ipv6h->saddr) + sizeof(ipv6h->daddr), 0);
752 	csum_pseudo_hdr = csum_add(csum_pseudo_hdr, (__force __wsum)ipv6h->payload_len);
753 	csum_pseudo_hdr = csum_add(csum_pseudo_hdr, (__force __wsum)ntohs(ipv6h->nexthdr));
754 
755 	skb->csum = csum_sub(hw_checksum, csum_pseudo_hdr);
756 	skb->csum = csum_add(skb->csum, csum_partial(ipv6h, sizeof(struct ipv6hdr), 0));
757 	return 0;
758 }
759 #endif
760 static int check_csum(struct mlx4_cqe *cqe, struct sk_buff *skb, void *va,
761 		      netdev_features_t dev_features)
762 {
763 	__wsum hw_checksum = 0;
764 
765 	void *hdr = (u8 *)va + sizeof(struct ethhdr);
766 
767 	hw_checksum = csum_unfold((__force __sum16)cqe->checksum);
768 
769 	if (cqe->vlan_my_qpn & cpu_to_be32(MLX4_CQE_CVLAN_PRESENT_MASK) &&
770 	    !(dev_features & NETIF_F_HW_VLAN_CTAG_RX)) {
771 		hw_checksum = get_fixed_vlan_csum(hw_checksum, hdr);
772 		hdr += sizeof(struct vlan_hdr);
773 	}
774 
775 	if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV4))
776 		get_fixed_ipv4_csum(hw_checksum, skb, hdr);
777 #if IS_ENABLED(CONFIG_IPV6)
778 	else if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV6))
779 		if (unlikely(get_fixed_ipv6_csum(hw_checksum, skb, hdr)))
780 			return -1;
781 #endif
782 	return 0;
783 }
784 
785 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
786 {
787 	struct mlx4_en_priv *priv = netdev_priv(dev);
788 	struct mlx4_en_dev *mdev = priv->mdev;
789 	struct mlx4_cqe *cqe;
790 	struct mlx4_en_rx_ring *ring = priv->rx_ring[cq->ring];
791 	struct mlx4_en_rx_alloc *frags;
792 	struct mlx4_en_rx_desc *rx_desc;
793 	struct bpf_prog *xdp_prog;
794 	int doorbell_pending;
795 	struct sk_buff *skb;
796 	int index;
797 	int nr;
798 	unsigned int length;
799 	int polled = 0;
800 	int ip_summed;
801 	int factor = priv->cqe_factor;
802 	u64 timestamp;
803 	bool l2_tunnel;
804 
805 	if (unlikely(!priv->port_up))
806 		return 0;
807 
808 	if (unlikely(budget <= 0))
809 		return polled;
810 
811 	/* Protect accesses to: ring->xdp_prog, priv->mac_hash list */
812 	rcu_read_lock();
813 	xdp_prog = rcu_dereference(ring->xdp_prog);
814 	doorbell_pending = 0;
815 
816 	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
817 	 * descriptor offset can be deduced from the CQE index instead of
818 	 * reading 'cqe->index' */
819 	index = cq->mcq.cons_index & ring->size_mask;
820 	cqe = mlx4_en_get_cqe(cq->buf, index, priv->cqe_size) + factor;
821 
822 	/* Process all completed CQEs */
823 	while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
824 		    cq->mcq.cons_index & cq->size)) {
825 
826 		frags = ring->rx_info + (index << priv->log_rx_info);
827 		rx_desc = ring->buf + (index << ring->log_stride);
828 
829 		/*
830 		 * make sure we read the CQE after we read the ownership bit
831 		 */
832 		dma_rmb();
833 
834 		/* Drop packet on bad receive or bad checksum */
835 		if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
836 						MLX4_CQE_OPCODE_ERROR)) {
837 			en_err(priv, "CQE completed in error - vendor syndrom:%d syndrom:%d\n",
838 			       ((struct mlx4_err_cqe *)cqe)->vendor_err_syndrome,
839 			       ((struct mlx4_err_cqe *)cqe)->syndrome);
840 			goto next;
841 		}
842 		if (unlikely(cqe->badfcs_enc & MLX4_CQE_BAD_FCS)) {
843 			en_dbg(RX_ERR, priv, "Accepted frame with bad FCS\n");
844 			goto next;
845 		}
846 
847 		/* Check if we need to drop the packet if SRIOV is not enabled
848 		 * and not performing the selftest or flb disabled
849 		 */
850 		if (priv->flags & MLX4_EN_FLAG_RX_FILTER_NEEDED) {
851 			struct ethhdr *ethh;
852 			dma_addr_t dma;
853 			/* Get pointer to first fragment since we haven't
854 			 * skb yet and cast it to ethhdr struct
855 			 */
856 			dma = be64_to_cpu(rx_desc->data[0].addr);
857 			dma_sync_single_for_cpu(priv->ddev, dma, sizeof(*ethh),
858 						DMA_FROM_DEVICE);
859 			ethh = (struct ethhdr *)(page_address(frags[0].page) +
860 						 frags[0].page_offset);
861 
862 			if (is_multicast_ether_addr(ethh->h_dest)) {
863 				struct mlx4_mac_entry *entry;
864 				struct hlist_head *bucket;
865 				unsigned int mac_hash;
866 
867 				/* Drop the packet, since HW loopback-ed it */
868 				mac_hash = ethh->h_source[MLX4_EN_MAC_HASH_IDX];
869 				bucket = &priv->mac_hash[mac_hash];
870 				hlist_for_each_entry_rcu(entry, bucket, hlist) {
871 					if (ether_addr_equal_64bits(entry->mac,
872 								    ethh->h_source))
873 						goto next;
874 				}
875 			}
876 		}
877 
878 		/*
879 		 * Packet is OK - process it.
880 		 */
881 		length = be32_to_cpu(cqe->byte_cnt);
882 		length -= ring->fcs_del;
883 		l2_tunnel = (dev->hw_enc_features & NETIF_F_RXCSUM) &&
884 			(cqe->vlan_my_qpn & cpu_to_be32(MLX4_CQE_L2_TUNNEL));
885 
886 		/* A bpf program gets first chance to drop the packet. It may
887 		 * read bytes but not past the end of the frag.
888 		 */
889 		if (xdp_prog) {
890 			struct xdp_buff xdp;
891 			dma_addr_t dma;
892 			u32 act;
893 
894 			dma = be64_to_cpu(rx_desc->data[0].addr);
895 			dma_sync_single_for_cpu(priv->ddev, dma,
896 						priv->frag_info[0].frag_size,
897 						DMA_FROM_DEVICE);
898 
899 			xdp.data = page_address(frags[0].page) +
900 							frags[0].page_offset;
901 			xdp.data_end = xdp.data + length;
902 
903 			act = bpf_prog_run_xdp(xdp_prog, &xdp);
904 			switch (act) {
905 			case XDP_PASS:
906 				break;
907 			case XDP_TX:
908 				if (likely(!mlx4_en_xmit_frame(ring, frags, dev,
909 							length, cq->ring,
910 							&doorbell_pending)))
911 					goto consumed;
912 				goto xdp_drop_no_cnt; /* Drop on xmit failure */
913 			default:
914 				bpf_warn_invalid_xdp_action(act);
915 			case XDP_ABORTED:
916 			case XDP_DROP:
917 				ring->xdp_drop++;
918 xdp_drop_no_cnt:
919 				if (likely(mlx4_en_rx_recycle(ring, frags)))
920 					goto consumed;
921 				goto next;
922 			}
923 		}
924 
925 		ring->bytes += length;
926 		ring->packets++;
927 
928 		if (likely(dev->features & NETIF_F_RXCSUM)) {
929 			if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_TCP |
930 						      MLX4_CQE_STATUS_UDP)) {
931 				if ((cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
932 				    cqe->checksum == cpu_to_be16(0xffff)) {
933 					ip_summed = CHECKSUM_UNNECESSARY;
934 					ring->csum_ok++;
935 				} else {
936 					ip_summed = CHECKSUM_NONE;
937 					ring->csum_none++;
938 				}
939 			} else {
940 				if (priv->flags & MLX4_EN_FLAG_RX_CSUM_NON_TCP_UDP &&
941 				    (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV4 |
942 							       MLX4_CQE_STATUS_IPV6))) {
943 					ip_summed = CHECKSUM_COMPLETE;
944 					ring->csum_complete++;
945 				} else {
946 					ip_summed = CHECKSUM_NONE;
947 					ring->csum_none++;
948 				}
949 			}
950 		} else {
951 			ip_summed = CHECKSUM_NONE;
952 			ring->csum_none++;
953 		}
954 
955 		/* This packet is eligible for GRO if it is:
956 		 * - DIX Ethernet (type interpretation)
957 		 * - TCP/IP (v4)
958 		 * - without IP options
959 		 * - not an IP fragment
960 		 */
961 		if (dev->features & NETIF_F_GRO) {
962 			struct sk_buff *gro_skb = napi_get_frags(&cq->napi);
963 			if (!gro_skb)
964 				goto next;
965 
966 			nr = mlx4_en_complete_rx_desc(priv,
967 				rx_desc, frags, gro_skb,
968 				length);
969 			if (!nr)
970 				goto next;
971 
972 			if (ip_summed == CHECKSUM_COMPLETE) {
973 				void *va = skb_frag_address(skb_shinfo(gro_skb)->frags);
974 				if (check_csum(cqe, gro_skb, va,
975 					       dev->features)) {
976 					ip_summed = CHECKSUM_NONE;
977 					ring->csum_none++;
978 					ring->csum_complete--;
979 				}
980 			}
981 
982 			skb_shinfo(gro_skb)->nr_frags = nr;
983 			gro_skb->len = length;
984 			gro_skb->data_len = length;
985 			gro_skb->ip_summed = ip_summed;
986 
987 			if (l2_tunnel && ip_summed == CHECKSUM_UNNECESSARY)
988 				gro_skb->csum_level = 1;
989 
990 			if ((cqe->vlan_my_qpn &
991 			    cpu_to_be32(MLX4_CQE_CVLAN_PRESENT_MASK)) &&
992 			    (dev->features & NETIF_F_HW_VLAN_CTAG_RX)) {
993 				u16 vid = be16_to_cpu(cqe->sl_vid);
994 
995 				__vlan_hwaccel_put_tag(gro_skb, htons(ETH_P_8021Q), vid);
996 			} else if ((be32_to_cpu(cqe->vlan_my_qpn) &
997 				  MLX4_CQE_SVLAN_PRESENT_MASK) &&
998 				 (dev->features & NETIF_F_HW_VLAN_STAG_RX)) {
999 				__vlan_hwaccel_put_tag(gro_skb,
1000 						       htons(ETH_P_8021AD),
1001 						       be16_to_cpu(cqe->sl_vid));
1002 			}
1003 
1004 			if (dev->features & NETIF_F_RXHASH)
1005 				skb_set_hash(gro_skb,
1006 					     be32_to_cpu(cqe->immed_rss_invalid),
1007 					     (ip_summed == CHECKSUM_UNNECESSARY) ?
1008 						PKT_HASH_TYPE_L4 :
1009 						PKT_HASH_TYPE_L3);
1010 
1011 			skb_record_rx_queue(gro_skb, cq->ring);
1012 
1013 			if (ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL) {
1014 				timestamp = mlx4_en_get_cqe_ts(cqe);
1015 				mlx4_en_fill_hwtstamps(mdev,
1016 						       skb_hwtstamps(gro_skb),
1017 						       timestamp);
1018 			}
1019 
1020 			napi_gro_frags(&cq->napi);
1021 			goto next;
1022 		}
1023 
1024 		/* GRO not possible, complete processing here */
1025 		skb = mlx4_en_rx_skb(priv, rx_desc, frags, length);
1026 		if (unlikely(!skb)) {
1027 			ring->dropped++;
1028 			goto next;
1029 		}
1030 
1031 		if (unlikely(priv->validate_loopback)) {
1032 			validate_loopback(priv, skb);
1033 			goto next;
1034 		}
1035 
1036 		if (ip_summed == CHECKSUM_COMPLETE) {
1037 			if (check_csum(cqe, skb, skb->data, dev->features)) {
1038 				ip_summed = CHECKSUM_NONE;
1039 				ring->csum_complete--;
1040 				ring->csum_none++;
1041 			}
1042 		}
1043 
1044 		skb->ip_summed = ip_summed;
1045 		skb->protocol = eth_type_trans(skb, dev);
1046 		skb_record_rx_queue(skb, cq->ring);
1047 
1048 		if (l2_tunnel && ip_summed == CHECKSUM_UNNECESSARY)
1049 			skb->csum_level = 1;
1050 
1051 		if (dev->features & NETIF_F_RXHASH)
1052 			skb_set_hash(skb,
1053 				     be32_to_cpu(cqe->immed_rss_invalid),
1054 				     (ip_summed == CHECKSUM_UNNECESSARY) ?
1055 					PKT_HASH_TYPE_L4 :
1056 					PKT_HASH_TYPE_L3);
1057 
1058 		if ((be32_to_cpu(cqe->vlan_my_qpn) &
1059 		    MLX4_CQE_CVLAN_PRESENT_MASK) &&
1060 		    (dev->features & NETIF_F_HW_VLAN_CTAG_RX))
1061 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), be16_to_cpu(cqe->sl_vid));
1062 		else if ((be32_to_cpu(cqe->vlan_my_qpn) &
1063 			  MLX4_CQE_SVLAN_PRESENT_MASK) &&
1064 			 (dev->features & NETIF_F_HW_VLAN_STAG_RX))
1065 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021AD),
1066 					       be16_to_cpu(cqe->sl_vid));
1067 
1068 		if (ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL) {
1069 			timestamp = mlx4_en_get_cqe_ts(cqe);
1070 			mlx4_en_fill_hwtstamps(mdev, skb_hwtstamps(skb),
1071 					       timestamp);
1072 		}
1073 
1074 		napi_gro_receive(&cq->napi, skb);
1075 next:
1076 		for (nr = 0; nr < priv->num_frags; nr++)
1077 			mlx4_en_free_frag(priv, frags, nr);
1078 
1079 consumed:
1080 		++cq->mcq.cons_index;
1081 		index = (cq->mcq.cons_index) & ring->size_mask;
1082 		cqe = mlx4_en_get_cqe(cq->buf, index, priv->cqe_size) + factor;
1083 		if (++polled == budget)
1084 			goto out;
1085 	}
1086 
1087 out:
1088 	rcu_read_unlock();
1089 
1090 	if (polled) {
1091 		if (doorbell_pending)
1092 			mlx4_en_xmit_doorbell(priv->tx_ring[TX_XDP][cq->ring]);
1093 
1094 		mlx4_cq_set_ci(&cq->mcq);
1095 		wmb(); /* ensure HW sees CQ consumer before we post new buffers */
1096 		ring->cons = cq->mcq.cons_index;
1097 	}
1098 	AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
1099 
1100 	if (mlx4_en_refill_rx_buffers(priv, ring))
1101 		mlx4_en_update_rx_prod_db(ring);
1102 
1103 	return polled;
1104 }
1105 
1106 
1107 void mlx4_en_rx_irq(struct mlx4_cq *mcq)
1108 {
1109 	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
1110 	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
1111 
1112 	if (likely(priv->port_up))
1113 		napi_schedule_irqoff(&cq->napi);
1114 	else
1115 		mlx4_en_arm_cq(priv, cq);
1116 }
1117 
1118 /* Rx CQ polling - called by NAPI */
1119 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget)
1120 {
1121 	struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
1122 	struct net_device *dev = cq->dev;
1123 	struct mlx4_en_priv *priv = netdev_priv(dev);
1124 	int done;
1125 
1126 	done = mlx4_en_process_rx_cq(dev, cq, budget);
1127 
1128 	/* If we used up all the quota - we're probably not done yet... */
1129 	if (done == budget) {
1130 		const struct cpumask *aff;
1131 		struct irq_data *idata;
1132 		int cpu_curr;
1133 
1134 		INC_PERF_COUNTER(priv->pstats.napi_quota);
1135 
1136 		cpu_curr = smp_processor_id();
1137 		idata = irq_desc_get_irq_data(cq->irq_desc);
1138 		aff = irq_data_get_affinity_mask(idata);
1139 
1140 		if (likely(cpumask_test_cpu(cpu_curr, aff)))
1141 			return budget;
1142 
1143 		/* Current cpu is not according to smp_irq_affinity -
1144 		 * probably affinity changed. Need to stop this NAPI
1145 		 * poll, and restart it on the right CPU.
1146 		 * Try to avoid returning a too small value (like 0),
1147 		 * to not fool net_rx_action() and its netdev_budget
1148 		 */
1149 		if (done)
1150 			done--;
1151 	}
1152 	/* Done for now */
1153 	if (napi_complete_done(napi, done))
1154 		mlx4_en_arm_cq(priv, cq);
1155 	return done;
1156 }
1157 
1158 static const int frag_sizes[] = {
1159 	FRAG_SZ0,
1160 	FRAG_SZ1,
1161 	FRAG_SZ2,
1162 	FRAG_SZ3
1163 };
1164 
1165 void mlx4_en_calc_rx_buf(struct net_device *dev)
1166 {
1167 	enum dma_data_direction dma_dir = PCI_DMA_FROMDEVICE;
1168 	struct mlx4_en_priv *priv = netdev_priv(dev);
1169 	int eff_mtu = MLX4_EN_EFF_MTU(dev->mtu);
1170 	int order = MLX4_EN_ALLOC_PREFER_ORDER;
1171 	u32 align = SMP_CACHE_BYTES;
1172 	int buf_size = 0;
1173 	int i = 0;
1174 
1175 	/* bpf requires buffers to be set up as 1 packet per page.
1176 	 * This only works when num_frags == 1.
1177 	 */
1178 	if (priv->tx_ring_num[TX_XDP]) {
1179 		dma_dir = PCI_DMA_BIDIRECTIONAL;
1180 		/* This will gain efficient xdp frame recycling at the expense
1181 		 * of more costly truesize accounting
1182 		 */
1183 		align = PAGE_SIZE;
1184 		order = 0;
1185 	}
1186 
1187 	while (buf_size < eff_mtu) {
1188 		priv->frag_info[i].order = order;
1189 		priv->frag_info[i].frag_size =
1190 			(eff_mtu > buf_size + frag_sizes[i]) ?
1191 				frag_sizes[i] : eff_mtu - buf_size;
1192 		priv->frag_info[i].frag_prefix_size = buf_size;
1193 		priv->frag_info[i].frag_stride =
1194 				ALIGN(priv->frag_info[i].frag_size, align);
1195 		priv->frag_info[i].dma_dir = dma_dir;
1196 		buf_size += priv->frag_info[i].frag_size;
1197 		i++;
1198 	}
1199 
1200 	priv->num_frags = i;
1201 	priv->rx_skb_size = eff_mtu;
1202 	priv->log_rx_info = ROUNDUP_LOG2(i * sizeof(struct mlx4_en_rx_alloc));
1203 
1204 	en_dbg(DRV, priv, "Rx buffer scatter-list (effective-mtu:%d num_frags:%d):\n",
1205 	       eff_mtu, priv->num_frags);
1206 	for (i = 0; i < priv->num_frags; i++) {
1207 		en_err(priv,
1208 		       "  frag:%d - size:%d prefix:%d stride:%d\n",
1209 		       i,
1210 		       priv->frag_info[i].frag_size,
1211 		       priv->frag_info[i].frag_prefix_size,
1212 		       priv->frag_info[i].frag_stride);
1213 	}
1214 }
1215 
1216 /* RSS related functions */
1217 
1218 static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
1219 				 struct mlx4_en_rx_ring *ring,
1220 				 enum mlx4_qp_state *state,
1221 				 struct mlx4_qp *qp)
1222 {
1223 	struct mlx4_en_dev *mdev = priv->mdev;
1224 	struct mlx4_qp_context *context;
1225 	int err = 0;
1226 
1227 	context = kmalloc(sizeof(*context), GFP_KERNEL);
1228 	if (!context)
1229 		return -ENOMEM;
1230 
1231 	err = mlx4_qp_alloc(mdev->dev, qpn, qp, GFP_KERNEL);
1232 	if (err) {
1233 		en_err(priv, "Failed to allocate qp #%x\n", qpn);
1234 		goto out;
1235 	}
1236 	qp->event = mlx4_en_sqp_event;
1237 
1238 	memset(context, 0, sizeof *context);
1239 	mlx4_en_fill_qp_context(priv, ring->actual_size, ring->stride, 0, 0,
1240 				qpn, ring->cqn, -1, context);
1241 	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);
1242 
1243 	/* Cancel FCS removal if FW allows */
1244 	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
1245 		context->param3 |= cpu_to_be32(1 << 29);
1246 		if (priv->dev->features & NETIF_F_RXFCS)
1247 			ring->fcs_del = 0;
1248 		else
1249 			ring->fcs_del = ETH_FCS_LEN;
1250 	} else
1251 		ring->fcs_del = 0;
1252 
1253 	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
1254 	if (err) {
1255 		mlx4_qp_remove(mdev->dev, qp);
1256 		mlx4_qp_free(mdev->dev, qp);
1257 	}
1258 	mlx4_en_update_rx_prod_db(ring);
1259 out:
1260 	kfree(context);
1261 	return err;
1262 }
1263 
1264 int mlx4_en_create_drop_qp(struct mlx4_en_priv *priv)
1265 {
1266 	int err;
1267 	u32 qpn;
1268 
1269 	err = mlx4_qp_reserve_range(priv->mdev->dev, 1, 1, &qpn,
1270 				    MLX4_RESERVE_A0_QP);
1271 	if (err) {
1272 		en_err(priv, "Failed reserving drop qpn\n");
1273 		return err;
1274 	}
1275 	err = mlx4_qp_alloc(priv->mdev->dev, qpn, &priv->drop_qp, GFP_KERNEL);
1276 	if (err) {
1277 		en_err(priv, "Failed allocating drop qp\n");
1278 		mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
1279 		return err;
1280 	}
1281 
1282 	return 0;
1283 }
1284 
1285 void mlx4_en_destroy_drop_qp(struct mlx4_en_priv *priv)
1286 {
1287 	u32 qpn;
1288 
1289 	qpn = priv->drop_qp.qpn;
1290 	mlx4_qp_remove(priv->mdev->dev, &priv->drop_qp);
1291 	mlx4_qp_free(priv->mdev->dev, &priv->drop_qp);
1292 	mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
1293 }
1294 
1295 /* Allocate rx qp's and configure them according to rss map */
1296 int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
1297 {
1298 	struct mlx4_en_dev *mdev = priv->mdev;
1299 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
1300 	struct mlx4_qp_context context;
1301 	struct mlx4_rss_context *rss_context;
1302 	int rss_rings;
1303 	void *ptr;
1304 	u8 rss_mask = (MLX4_RSS_IPV4 | MLX4_RSS_TCP_IPV4 | MLX4_RSS_IPV6 |
1305 			MLX4_RSS_TCP_IPV6);
1306 	int i, qpn;
1307 	int err = 0;
1308 	int good_qps = 0;
1309 
1310 	en_dbg(DRV, priv, "Configuring rss steering\n");
1311 	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
1312 				    priv->rx_ring_num,
1313 				    &rss_map->base_qpn, 0);
1314 	if (err) {
1315 		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
1316 		return err;
1317 	}
1318 
1319 	for (i = 0; i < priv->rx_ring_num; i++) {
1320 		qpn = rss_map->base_qpn + i;
1321 		err = mlx4_en_config_rss_qp(priv, qpn, priv->rx_ring[i],
1322 					    &rss_map->state[i],
1323 					    &rss_map->qps[i]);
1324 		if (err)
1325 			goto rss_err;
1326 
1327 		++good_qps;
1328 	}
1329 
1330 	/* Configure RSS indirection qp */
1331 	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp, GFP_KERNEL);
1332 	if (err) {
1333 		en_err(priv, "Failed to allocate RSS indirection QP\n");
1334 		goto rss_err;
1335 	}
1336 	rss_map->indir_qp.event = mlx4_en_sqp_event;
1337 	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
1338 				priv->rx_ring[0]->cqn, -1, &context);
1339 
1340 	if (!priv->prof->rss_rings || priv->prof->rss_rings > priv->rx_ring_num)
1341 		rss_rings = priv->rx_ring_num;
1342 	else
1343 		rss_rings = priv->prof->rss_rings;
1344 
1345 	ptr = ((void *) &context) + offsetof(struct mlx4_qp_context, pri_path)
1346 					+ MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
1347 	rss_context = ptr;
1348 	rss_context->base_qpn = cpu_to_be32(ilog2(rss_rings) << 24 |
1349 					    (rss_map->base_qpn));
1350 	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
1351 	if (priv->mdev->profile.udp_rss) {
1352 		rss_mask |=  MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6;
1353 		rss_context->base_qpn_udp = rss_context->default_qpn;
1354 	}
1355 
1356 	if (mdev->dev->caps.tunnel_offload_mode == MLX4_TUNNEL_OFFLOAD_MODE_VXLAN) {
1357 		en_info(priv, "Setting RSS context tunnel type to RSS on inner headers\n");
1358 		rss_mask |= MLX4_RSS_BY_INNER_HEADERS;
1359 	}
1360 
1361 	rss_context->flags = rss_mask;
1362 	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
1363 	if (priv->rss_hash_fn == ETH_RSS_HASH_XOR) {
1364 		rss_context->hash_fn = MLX4_RSS_HASH_XOR;
1365 	} else if (priv->rss_hash_fn == ETH_RSS_HASH_TOP) {
1366 		rss_context->hash_fn = MLX4_RSS_HASH_TOP;
1367 		memcpy(rss_context->rss_key, priv->rss_key,
1368 		       MLX4_EN_RSS_KEY_SIZE);
1369 	} else {
1370 		en_err(priv, "Unknown RSS hash function requested\n");
1371 		err = -EINVAL;
1372 		goto indir_err;
1373 	}
1374 	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
1375 			       &rss_map->indir_qp, &rss_map->indir_state);
1376 	if (err)
1377 		goto indir_err;
1378 
1379 	return 0;
1380 
1381 indir_err:
1382 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1383 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
1384 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
1385 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
1386 rss_err:
1387 	for (i = 0; i < good_qps; i++) {
1388 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1389 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1390 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1391 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1392 	}
1393 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1394 	return err;
1395 }
1396 
1397 void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
1398 {
1399 	struct mlx4_en_dev *mdev = priv->mdev;
1400 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
1401 	int i;
1402 
1403 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1404 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
1405 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
1406 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
1407 
1408 	for (i = 0; i < priv->rx_ring_num; i++) {
1409 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1410 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1411 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1412 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1413 	}
1414 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1415 }
1416