xref: /linux/drivers/net/ethernet/mellanox/mlx4/en_rx.c (revision 71dfa617ea9f18e4585fe78364217cd32b1fc382)
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 <linux/bpf.h>
35 #include <linux/bpf_trace.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 #include <net/ip.h>
47 #if IS_ENABLED(CONFIG_IPV6)
48 #include <net/ip6_checksum.h>
49 #endif
50 
51 #include "mlx4_en.h"
52 
53 static int mlx4_alloc_page(struct mlx4_en_priv *priv,
54 			   struct mlx4_en_rx_alloc *frag,
55 			   gfp_t gfp)
56 {
57 	struct page *page;
58 	dma_addr_t dma;
59 
60 	page = alloc_page(gfp);
61 	if (unlikely(!page))
62 		return -ENOMEM;
63 	dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE, priv->dma_dir);
64 	if (unlikely(dma_mapping_error(priv->ddev, dma))) {
65 		__free_page(page);
66 		return -ENOMEM;
67 	}
68 	frag->page = page;
69 	frag->dma = dma;
70 	frag->page_offset = priv->rx_headroom;
71 	return 0;
72 }
73 
74 static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv,
75 			       struct mlx4_en_rx_ring *ring,
76 			       struct mlx4_en_rx_desc *rx_desc,
77 			       struct mlx4_en_rx_alloc *frags,
78 			       gfp_t gfp)
79 {
80 	int i;
81 
82 	for (i = 0; i < priv->num_frags; i++, frags++) {
83 		if (!frags->page) {
84 			if (mlx4_alloc_page(priv, frags, gfp))
85 				return -ENOMEM;
86 			ring->rx_alloc_pages++;
87 		}
88 		rx_desc->data[i].addr = cpu_to_be64(frags->dma +
89 						    frags->page_offset);
90 	}
91 	return 0;
92 }
93 
94 static void mlx4_en_free_frag(const struct mlx4_en_priv *priv,
95 			      struct mlx4_en_rx_alloc *frag)
96 {
97 	if (frag->page) {
98 		dma_unmap_page(priv->ddev, frag->dma,
99 			       PAGE_SIZE, priv->dma_dir);
100 		__free_page(frag->page);
101 	}
102 	/* We need to clear all fields, otherwise a change of priv->log_rx_info
103 	 * could lead to see garbage later in frag->page.
104 	 */
105 	memset(frag, 0, sizeof(*frag));
106 }
107 
108 static void mlx4_en_init_rx_desc(const struct mlx4_en_priv *priv,
109 				 struct mlx4_en_rx_ring *ring, int index)
110 {
111 	struct mlx4_en_rx_desc *rx_desc = ring->buf + ring->stride * index;
112 	int possible_frags;
113 	int i;
114 
115 	/* Set size and memtype fields */
116 	for (i = 0; i < priv->num_frags; i++) {
117 		rx_desc->data[i].byte_count =
118 			cpu_to_be32(priv->frag_info[i].frag_size);
119 		rx_desc->data[i].lkey = cpu_to_be32(priv->mdev->mr.key);
120 	}
121 
122 	/* If the number of used fragments does not fill up the ring stride,
123 	 * remaining (unused) fragments must be padded with null address/size
124 	 * and a special memory key */
125 	possible_frags = (ring->stride - sizeof(struct mlx4_en_rx_desc)) / DS_SIZE;
126 	for (i = priv->num_frags; i < possible_frags; i++) {
127 		rx_desc->data[i].byte_count = 0;
128 		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
129 		rx_desc->data[i].addr = 0;
130 	}
131 }
132 
133 static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
134 				   struct mlx4_en_rx_ring *ring, int index,
135 				   gfp_t gfp)
136 {
137 	struct mlx4_en_rx_desc *rx_desc = ring->buf +
138 		(index << ring->log_stride);
139 	struct mlx4_en_rx_alloc *frags = ring->rx_info +
140 					(index << priv->log_rx_info);
141 	if (likely(ring->page_cache.index > 0)) {
142 		/* XDP uses a single page per frame */
143 		if (!frags->page) {
144 			ring->page_cache.index--;
145 			frags->page = ring->page_cache.buf[ring->page_cache.index].page;
146 			frags->dma  = ring->page_cache.buf[ring->page_cache.index].dma;
147 		}
148 		frags->page_offset = XDP_PACKET_HEADROOM;
149 		rx_desc->data[0].addr = cpu_to_be64(frags->dma +
150 						    XDP_PACKET_HEADROOM);
151 		return 0;
152 	}
153 
154 	return mlx4_en_alloc_frags(priv, ring, rx_desc, frags, gfp);
155 }
156 
157 static bool mlx4_en_is_ring_empty(const struct mlx4_en_rx_ring *ring)
158 {
159 	return ring->prod == ring->cons;
160 }
161 
162 static inline void mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
163 {
164 	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
165 }
166 
167 /* slow path */
168 static void mlx4_en_free_rx_desc(const struct mlx4_en_priv *priv,
169 				 struct mlx4_en_rx_ring *ring,
170 				 int index)
171 {
172 	struct mlx4_en_rx_alloc *frags;
173 	int nr;
174 
175 	frags = ring->rx_info + (index << priv->log_rx_info);
176 	for (nr = 0; nr < priv->num_frags; nr++) {
177 		en_dbg(DRV, priv, "Freeing fragment:%d\n", nr);
178 		mlx4_en_free_frag(priv, frags + nr);
179 	}
180 }
181 
182 /* Function not in fast-path */
183 static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
184 {
185 	struct mlx4_en_rx_ring *ring;
186 	int ring_ind;
187 	int buf_ind;
188 	int new_size;
189 
190 	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
191 		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
192 			ring = priv->rx_ring[ring_ind];
193 
194 			if (mlx4_en_prepare_rx_desc(priv, ring,
195 						    ring->actual_size,
196 						    GFP_KERNEL)) {
197 				if (ring->actual_size < MLX4_EN_MIN_RX_SIZE) {
198 					en_err(priv, "Failed to allocate enough rx buffers\n");
199 					return -ENOMEM;
200 				} else {
201 					new_size = rounddown_pow_of_two(ring->actual_size);
202 					en_warn(priv, "Only %d buffers allocated reducing ring size to %d\n",
203 						ring->actual_size, new_size);
204 					goto reduce_rings;
205 				}
206 			}
207 			ring->actual_size++;
208 			ring->prod++;
209 		}
210 	}
211 	return 0;
212 
213 reduce_rings:
214 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
215 		ring = priv->rx_ring[ring_ind];
216 		while (ring->actual_size > new_size) {
217 			ring->actual_size--;
218 			ring->prod--;
219 			mlx4_en_free_rx_desc(priv, ring, ring->actual_size);
220 		}
221 	}
222 
223 	return 0;
224 }
225 
226 static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
227 				struct mlx4_en_rx_ring *ring)
228 {
229 	int index;
230 
231 	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
232 	       ring->cons, ring->prod);
233 
234 	/* Unmap and free Rx buffers */
235 	for (index = 0; index < ring->size; index++) {
236 		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
237 		mlx4_en_free_rx_desc(priv, ring, index);
238 	}
239 	ring->cons = 0;
240 	ring->prod = 0;
241 }
242 
243 void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev)
244 {
245 	int i;
246 	int num_of_eqs;
247 	int num_rx_rings;
248 	struct mlx4_dev *dev = mdev->dev;
249 
250 	mlx4_foreach_port(i, dev, MLX4_PORT_TYPE_ETH) {
251 		num_of_eqs = max_t(int, MIN_RX_RINGS,
252 				   min_t(int,
253 					 mlx4_get_eqs_per_port(mdev->dev, i),
254 					 DEF_RX_RINGS));
255 
256 		num_rx_rings = mlx4_low_memory_profile() ? MIN_RX_RINGS :
257 			min_t(int, num_of_eqs, num_online_cpus());
258 		mdev->profile.prof[i].rx_ring_num =
259 			rounddown_pow_of_two(num_rx_rings);
260 	}
261 }
262 
263 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
264 			   struct mlx4_en_rx_ring **pring,
265 			   u32 size, u16 stride, int node, int queue_index)
266 {
267 	struct mlx4_en_dev *mdev = priv->mdev;
268 	struct mlx4_en_rx_ring *ring;
269 	int err = -ENOMEM;
270 	int tmp;
271 
272 	ring = kzalloc_node(sizeof(*ring), GFP_KERNEL, node);
273 	if (!ring) {
274 		en_err(priv, "Failed to allocate RX ring structure\n");
275 		return -ENOMEM;
276 	}
277 
278 	ring->prod = 0;
279 	ring->cons = 0;
280 	ring->size = size;
281 	ring->size_mask = size - 1;
282 	ring->stride = stride;
283 	ring->log_stride = ffs(ring->stride) - 1;
284 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
285 
286 	if (xdp_rxq_info_reg(&ring->xdp_rxq, priv->dev, queue_index, 0) < 0)
287 		goto err_ring;
288 
289 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
290 					sizeof(struct mlx4_en_rx_alloc));
291 	ring->rx_info = kvzalloc_node(tmp, GFP_KERNEL, node);
292 	if (!ring->rx_info) {
293 		err = -ENOMEM;
294 		goto err_xdp_info;
295 	}
296 
297 	en_dbg(DRV, priv, "Allocated rx_info ring at addr:%p size:%d\n",
298 		 ring->rx_info, tmp);
299 
300 	/* Allocate HW buffers on provided NUMA node */
301 	set_dev_node(&mdev->dev->persist->pdev->dev, node);
302 	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
303 	set_dev_node(&mdev->dev->persist->pdev->dev, mdev->dev->numa_node);
304 	if (err)
305 		goto err_info;
306 
307 	ring->buf = ring->wqres.buf.direct.buf;
308 
309 	ring->hwtstamp_rx_filter = priv->hwtstamp_config.rx_filter;
310 
311 	*pring = ring;
312 	return 0;
313 
314 err_info:
315 	kvfree(ring->rx_info);
316 	ring->rx_info = NULL;
317 err_xdp_info:
318 	xdp_rxq_info_unreg(&ring->xdp_rxq);
319 err_ring:
320 	kfree(ring);
321 	*pring = NULL;
322 
323 	return err;
324 }
325 
326 int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
327 {
328 	struct mlx4_en_rx_ring *ring;
329 	int i;
330 	int ring_ind;
331 	int err;
332 	int stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
333 					DS_SIZE * priv->num_frags);
334 
335 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
336 		ring = priv->rx_ring[ring_ind];
337 
338 		ring->prod = 0;
339 		ring->cons = 0;
340 		ring->actual_size = 0;
341 		ring->cqn = priv->rx_cq[ring_ind]->mcq.cqn;
342 
343 		ring->stride = stride;
344 		if (ring->stride <= TXBB_SIZE) {
345 			/* Stamp first unused send wqe */
346 			__be32 *ptr = (__be32 *)ring->buf;
347 			__be32 stamp = cpu_to_be32(1 << STAMP_SHIFT);
348 			*ptr = stamp;
349 			/* Move pointer to start of rx section */
350 			ring->buf += TXBB_SIZE;
351 		}
352 
353 		ring->log_stride = ffs(ring->stride) - 1;
354 		ring->buf_size = ring->size * ring->stride;
355 
356 		memset(ring->buf, 0, ring->buf_size);
357 		mlx4_en_update_rx_prod_db(ring);
358 
359 		/* Initialize all descriptors */
360 		for (i = 0; i < ring->size; i++)
361 			mlx4_en_init_rx_desc(priv, ring, i);
362 	}
363 	err = mlx4_en_fill_rx_buffers(priv);
364 	if (err)
365 		goto err_buffers;
366 
367 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
368 		ring = priv->rx_ring[ring_ind];
369 
370 		ring->size_mask = ring->actual_size - 1;
371 		mlx4_en_update_rx_prod_db(ring);
372 	}
373 
374 	return 0;
375 
376 err_buffers:
377 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
378 		mlx4_en_free_rx_buf(priv, priv->rx_ring[ring_ind]);
379 
380 	ring_ind = priv->rx_ring_num - 1;
381 	while (ring_ind >= 0) {
382 		if (priv->rx_ring[ring_ind]->stride <= TXBB_SIZE)
383 			priv->rx_ring[ring_ind]->buf -= TXBB_SIZE;
384 		ring_ind--;
385 	}
386 	return err;
387 }
388 
389 /* We recover from out of memory by scheduling our napi poll
390  * function (mlx4_en_process_cq), which tries to allocate
391  * all missing RX buffers (call to mlx4_en_refill_rx_buffers).
392  */
393 void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv)
394 {
395 	int ring;
396 
397 	if (!priv->port_up)
398 		return;
399 
400 	for (ring = 0; ring < priv->rx_ring_num; ring++) {
401 		if (mlx4_en_is_ring_empty(priv->rx_ring[ring])) {
402 			local_bh_disable();
403 			napi_schedule(&priv->rx_cq[ring]->napi);
404 			local_bh_enable();
405 		}
406 	}
407 }
408 
409 /* When the rx ring is running in page-per-packet mode, a released frame can go
410  * directly into a small cache, to avoid unmapping or touching the page
411  * allocator. In bpf prog performance scenarios, buffers are either forwarded
412  * or dropped, never converted to skbs, so every page can come directly from
413  * this cache when it is sized to be a multiple of the napi budget.
414  */
415 bool mlx4_en_rx_recycle(struct mlx4_en_rx_ring *ring,
416 			struct mlx4_en_rx_alloc *frame)
417 {
418 	struct mlx4_en_page_cache *cache = &ring->page_cache;
419 
420 	if (cache->index >= MLX4_EN_CACHE_SIZE)
421 		return false;
422 
423 	cache->buf[cache->index].page = frame->page;
424 	cache->buf[cache->index].dma = frame->dma;
425 	cache->index++;
426 	return true;
427 }
428 
429 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
430 			     struct mlx4_en_rx_ring **pring,
431 			     u32 size, u16 stride)
432 {
433 	struct mlx4_en_dev *mdev = priv->mdev;
434 	struct mlx4_en_rx_ring *ring = *pring;
435 	struct bpf_prog *old_prog;
436 
437 	old_prog = rcu_dereference_protected(
438 					ring->xdp_prog,
439 					lockdep_is_held(&mdev->state_lock));
440 	if (old_prog)
441 		bpf_prog_put(old_prog);
442 	xdp_rxq_info_unreg(&ring->xdp_rxq);
443 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
444 	kvfree(ring->rx_info);
445 	ring->rx_info = NULL;
446 	kfree(ring);
447 	*pring = NULL;
448 }
449 
450 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
451 				struct mlx4_en_rx_ring *ring)
452 {
453 	int i;
454 
455 	for (i = 0; i < ring->page_cache.index; i++) {
456 		dma_unmap_page(priv->ddev, ring->page_cache.buf[i].dma,
457 			       PAGE_SIZE, priv->dma_dir);
458 		put_page(ring->page_cache.buf[i].page);
459 	}
460 	ring->page_cache.index = 0;
461 	mlx4_en_free_rx_buf(priv, ring);
462 	if (ring->stride <= TXBB_SIZE)
463 		ring->buf -= TXBB_SIZE;
464 }
465 
466 
467 static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
468 				    struct mlx4_en_rx_alloc *frags,
469 				    struct sk_buff *skb,
470 				    int length)
471 {
472 	const struct mlx4_en_frag_info *frag_info = priv->frag_info;
473 	unsigned int truesize = 0;
474 	bool release = true;
475 	int nr, frag_size;
476 	struct page *page;
477 	dma_addr_t dma;
478 
479 	/* Collect used fragments while replacing them in the HW descriptors */
480 	for (nr = 0;; frags++) {
481 		frag_size = min_t(int, length, frag_info->frag_size);
482 
483 		page = frags->page;
484 		if (unlikely(!page))
485 			goto fail;
486 
487 		dma = frags->dma;
488 		dma_sync_single_range_for_cpu(priv->ddev, dma, frags->page_offset,
489 					      frag_size, priv->dma_dir);
490 
491 		__skb_fill_page_desc(skb, nr, page, frags->page_offset,
492 				     frag_size);
493 
494 		truesize += frag_info->frag_stride;
495 		if (frag_info->frag_stride == PAGE_SIZE / 2) {
496 			frags->page_offset ^= PAGE_SIZE / 2;
497 			release = page_count(page) != 1 ||
498 				  page_is_pfmemalloc(page) ||
499 				  page_to_nid(page) != numa_mem_id();
500 		} else if (!priv->rx_headroom) {
501 			/* rx_headroom for non XDP setup is always 0.
502 			 * When XDP is set, the above condition will
503 			 * guarantee page is always released.
504 			 */
505 			u32 sz_align = ALIGN(frag_size, SMP_CACHE_BYTES);
506 
507 			frags->page_offset += sz_align;
508 			release = frags->page_offset + frag_info->frag_size > PAGE_SIZE;
509 		}
510 		if (release) {
511 			dma_unmap_page(priv->ddev, dma, PAGE_SIZE, priv->dma_dir);
512 			frags->page = NULL;
513 		} else {
514 			page_ref_inc(page);
515 		}
516 
517 		nr++;
518 		length -= frag_size;
519 		if (!length)
520 			break;
521 		frag_info++;
522 	}
523 	skb->truesize += truesize;
524 	return nr;
525 
526 fail:
527 	while (nr > 0) {
528 		nr--;
529 		__skb_frag_unref(skb_shinfo(skb)->frags + nr, false);
530 	}
531 	return 0;
532 }
533 
534 static void validate_loopback(struct mlx4_en_priv *priv, void *va)
535 {
536 	const unsigned char *data = va + ETH_HLEN;
537 	int i;
538 
539 	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++) {
540 		if (data[i] != (unsigned char)i)
541 			return;
542 	}
543 	/* Loopback found */
544 	priv->loopback_ok = 1;
545 }
546 
547 static void mlx4_en_refill_rx_buffers(struct mlx4_en_priv *priv,
548 				      struct mlx4_en_rx_ring *ring)
549 {
550 	u32 missing = ring->actual_size - (ring->prod - ring->cons);
551 
552 	/* Try to batch allocations, but not too much. */
553 	if (missing < 8)
554 		return;
555 	do {
556 		if (mlx4_en_prepare_rx_desc(priv, ring,
557 					    ring->prod & ring->size_mask,
558 					    GFP_ATOMIC | __GFP_MEMALLOC))
559 			break;
560 		ring->prod++;
561 	} while (likely(--missing));
562 
563 	mlx4_en_update_rx_prod_db(ring);
564 }
565 
566 /* When hardware doesn't strip the vlan, we need to calculate the checksum
567  * over it and add it to the hardware's checksum calculation
568  */
569 static inline __wsum get_fixed_vlan_csum(__wsum hw_checksum,
570 					 struct vlan_hdr *vlanh)
571 {
572 	return csum_add(hw_checksum, *(__wsum *)vlanh);
573 }
574 
575 /* Although the stack expects checksum which doesn't include the pseudo
576  * header, the HW adds it. To address that, we are subtracting the pseudo
577  * header checksum from the checksum value provided by the HW.
578  */
579 static int get_fixed_ipv4_csum(__wsum hw_checksum, struct sk_buff *skb,
580 			       struct iphdr *iph)
581 {
582 	__u16 length_for_csum = 0;
583 	__wsum csum_pseudo_header = 0;
584 	__u8 ipproto = iph->protocol;
585 
586 	if (unlikely(ipproto == IPPROTO_SCTP))
587 		return -1;
588 
589 	length_for_csum = (be16_to_cpu(iph->tot_len) - (iph->ihl << 2));
590 	csum_pseudo_header = csum_tcpudp_nofold(iph->saddr, iph->daddr,
591 						length_for_csum, ipproto, 0);
592 	skb->csum = csum_sub(hw_checksum, csum_pseudo_header);
593 	return 0;
594 }
595 
596 #if IS_ENABLED(CONFIG_IPV6)
597 /* In IPv6 packets, hw_checksum lacks 6 bytes from IPv6 header:
598  * 4 first bytes : priority, version, flow_lbl
599  * and 2 additional bytes : nexthdr, hop_limit.
600  */
601 static int get_fixed_ipv6_csum(__wsum hw_checksum, struct sk_buff *skb,
602 			       struct ipv6hdr *ipv6h)
603 {
604 	__u8 nexthdr = ipv6h->nexthdr;
605 	__wsum temp;
606 
607 	if (unlikely(nexthdr == IPPROTO_FRAGMENT ||
608 		     nexthdr == IPPROTO_HOPOPTS ||
609 		     nexthdr == IPPROTO_SCTP))
610 		return -1;
611 
612 	/* priority, version, flow_lbl */
613 	temp = csum_add(hw_checksum, *(__wsum *)ipv6h);
614 	/* nexthdr and hop_limit */
615 	skb->csum = csum_add(temp, (__force __wsum)*(__be16 *)&ipv6h->nexthdr);
616 	return 0;
617 }
618 #endif
619 
620 #define short_frame(size) ((size) <= ETH_ZLEN + ETH_FCS_LEN)
621 
622 /* We reach this function only after checking that any of
623  * the (IPv4 | IPv6) bits are set in cqe->status.
624  */
625 static int check_csum(struct mlx4_cqe *cqe, struct sk_buff *skb, void *va,
626 		      netdev_features_t dev_features)
627 {
628 	__wsum hw_checksum = 0;
629 	void *hdr;
630 
631 	/* CQE csum doesn't cover padding octets in short ethernet
632 	 * frames. And the pad field is appended prior to calculating
633 	 * and appending the FCS field.
634 	 *
635 	 * Detecting these padded frames requires to verify and parse
636 	 * IP headers, so we simply force all those small frames to skip
637 	 * checksum complete.
638 	 */
639 	if (short_frame(skb->len))
640 		return -EINVAL;
641 
642 	hdr = (u8 *)va + sizeof(struct ethhdr);
643 	hw_checksum = csum_unfold((__force __sum16)cqe->checksum);
644 
645 	if (cqe->vlan_my_qpn & cpu_to_be32(MLX4_CQE_CVLAN_PRESENT_MASK) &&
646 	    !(dev_features & NETIF_F_HW_VLAN_CTAG_RX)) {
647 		hw_checksum = get_fixed_vlan_csum(hw_checksum, hdr);
648 		hdr += sizeof(struct vlan_hdr);
649 	}
650 
651 #if IS_ENABLED(CONFIG_IPV6)
652 	if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV6))
653 		return get_fixed_ipv6_csum(hw_checksum, skb, hdr);
654 #endif
655 	return get_fixed_ipv4_csum(hw_checksum, skb, hdr);
656 }
657 
658 #if IS_ENABLED(CONFIG_IPV6)
659 #define MLX4_CQE_STATUS_IP_ANY (MLX4_CQE_STATUS_IPV4 | MLX4_CQE_STATUS_IPV6)
660 #else
661 #define MLX4_CQE_STATUS_IP_ANY (MLX4_CQE_STATUS_IPV4)
662 #endif
663 
664 struct mlx4_en_xdp_buff {
665 	struct xdp_buff xdp;
666 	struct mlx4_cqe *cqe;
667 	struct mlx4_en_dev *mdev;
668 	struct mlx4_en_rx_ring *ring;
669 	struct net_device *dev;
670 };
671 
672 int mlx4_en_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
673 {
674 	struct mlx4_en_xdp_buff *_ctx = (void *)ctx;
675 
676 	if (unlikely(_ctx->ring->hwtstamp_rx_filter != HWTSTAMP_FILTER_ALL))
677 		return -ENODATA;
678 
679 	*timestamp = mlx4_en_get_hwtstamp(_ctx->mdev,
680 					  mlx4_en_get_cqe_ts(_ctx->cqe));
681 	return 0;
682 }
683 
684 int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
685 			enum xdp_rss_hash_type *rss_type)
686 {
687 	struct mlx4_en_xdp_buff *_ctx = (void *)ctx;
688 	struct mlx4_cqe *cqe = _ctx->cqe;
689 	enum xdp_rss_hash_type xht = 0;
690 	__be16 status;
691 
692 	if (unlikely(!(_ctx->dev->features & NETIF_F_RXHASH)))
693 		return -ENODATA;
694 
695 	*hash = be32_to_cpu(cqe->immed_rss_invalid);
696 	status = cqe->status;
697 	if (status & cpu_to_be16(MLX4_CQE_STATUS_TCP))
698 		xht = XDP_RSS_L4_TCP;
699 	if (status & cpu_to_be16(MLX4_CQE_STATUS_UDP))
700 		xht = XDP_RSS_L4_UDP;
701 	if (status & cpu_to_be16(MLX4_CQE_STATUS_IPV4 | MLX4_CQE_STATUS_IPV4F))
702 		xht |= XDP_RSS_L3_IPV4;
703 	if (status & cpu_to_be16(MLX4_CQE_STATUS_IPV6)) {
704 		xht |= XDP_RSS_L3_IPV6;
705 		if (cqe->ipv6_ext_mask)
706 			xht |= XDP_RSS_L3_DYNHDR;
707 	}
708 	*rss_type = xht;
709 
710 	return 0;
711 }
712 
713 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
714 {
715 	struct mlx4_en_priv *priv = netdev_priv(dev);
716 	struct mlx4_en_xdp_buff mxbuf = {};
717 	int factor = priv->cqe_factor;
718 	struct mlx4_en_rx_ring *ring;
719 	struct bpf_prog *xdp_prog;
720 	int cq_ring = cq->ring;
721 	bool doorbell_pending;
722 	bool xdp_redir_flush;
723 	struct mlx4_cqe *cqe;
724 	int polled = 0;
725 	int index;
726 
727 	if (unlikely(!priv->port_up || budget <= 0))
728 		return 0;
729 
730 	ring = priv->rx_ring[cq_ring];
731 
732 	xdp_prog = rcu_dereference_bh(ring->xdp_prog);
733 	xdp_init_buff(&mxbuf.xdp, priv->frag_info[0].frag_stride, &ring->xdp_rxq);
734 	doorbell_pending = false;
735 	xdp_redir_flush = false;
736 
737 	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
738 	 * descriptor offset can be deduced from the CQE index instead of
739 	 * reading 'cqe->index' */
740 	index = cq->mcq.cons_index & ring->size_mask;
741 	cqe = mlx4_en_get_cqe(cq->buf, index, priv->cqe_size) + factor;
742 
743 	/* Process all completed CQEs */
744 	while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
745 		    cq->mcq.cons_index & cq->size)) {
746 		struct mlx4_en_rx_alloc *frags;
747 		enum pkt_hash_types hash_type;
748 		struct sk_buff *skb;
749 		unsigned int length;
750 		int ip_summed;
751 		void *va;
752 		int nr;
753 
754 		frags = ring->rx_info + (index << priv->log_rx_info);
755 		va = page_address(frags[0].page) + frags[0].page_offset;
756 		net_prefetchw(va);
757 		/*
758 		 * make sure we read the CQE after we read the ownership bit
759 		 */
760 		dma_rmb();
761 
762 		/* Drop packet on bad receive or bad checksum */
763 		if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
764 						MLX4_CQE_OPCODE_ERROR)) {
765 			en_err(priv, "CQE completed in error - vendor syndrome:%d syndrome:%d\n",
766 			       ((struct mlx4_err_cqe *)cqe)->vendor_err_syndrome,
767 			       ((struct mlx4_err_cqe *)cqe)->syndrome);
768 			goto next;
769 		}
770 		if (unlikely(cqe->badfcs_enc & MLX4_CQE_BAD_FCS)) {
771 			en_dbg(RX_ERR, priv, "Accepted frame with bad FCS\n");
772 			goto next;
773 		}
774 
775 		/* Check if we need to drop the packet if SRIOV is not enabled
776 		 * and not performing the selftest or flb disabled
777 		 */
778 		if (priv->flags & MLX4_EN_FLAG_RX_FILTER_NEEDED) {
779 			const struct ethhdr *ethh = va;
780 			dma_addr_t dma;
781 			/* Get pointer to first fragment since we haven't
782 			 * skb yet and cast it to ethhdr struct
783 			 */
784 			dma = frags[0].dma + frags[0].page_offset;
785 			dma_sync_single_for_cpu(priv->ddev, dma, sizeof(*ethh),
786 						DMA_FROM_DEVICE);
787 
788 			if (is_multicast_ether_addr(ethh->h_dest)) {
789 				struct mlx4_mac_entry *entry;
790 				struct hlist_head *bucket;
791 				unsigned int mac_hash;
792 
793 				/* Drop the packet, since HW loopback-ed it */
794 				mac_hash = ethh->h_source[MLX4_EN_MAC_HASH_IDX];
795 				bucket = &priv->mac_hash[mac_hash];
796 				hlist_for_each_entry_rcu_bh(entry, bucket, hlist) {
797 					if (ether_addr_equal_64bits(entry->mac,
798 								    ethh->h_source))
799 						goto next;
800 				}
801 			}
802 		}
803 
804 		if (unlikely(priv->validate_loopback)) {
805 			validate_loopback(priv, va);
806 			goto next;
807 		}
808 
809 		/*
810 		 * Packet is OK - process it.
811 		 */
812 		length = be32_to_cpu(cqe->byte_cnt);
813 		length -= ring->fcs_del;
814 
815 		/* A bpf program gets first chance to drop the packet. It may
816 		 * read bytes but not past the end of the frag.
817 		 */
818 		if (xdp_prog) {
819 			dma_addr_t dma;
820 			void *orig_data;
821 			u32 act;
822 
823 			dma = frags[0].dma + frags[0].page_offset;
824 			dma_sync_single_for_cpu(priv->ddev, dma,
825 						priv->frag_info[0].frag_size,
826 						DMA_FROM_DEVICE);
827 
828 			xdp_prepare_buff(&mxbuf.xdp, va - frags[0].page_offset,
829 					 frags[0].page_offset, length, true);
830 			orig_data = mxbuf.xdp.data;
831 			mxbuf.cqe = cqe;
832 			mxbuf.mdev = priv->mdev;
833 			mxbuf.ring = ring;
834 			mxbuf.dev = dev;
835 
836 			act = bpf_prog_run_xdp(xdp_prog, &mxbuf.xdp);
837 
838 			length = mxbuf.xdp.data_end - mxbuf.xdp.data;
839 			if (mxbuf.xdp.data != orig_data) {
840 				frags[0].page_offset = mxbuf.xdp.data -
841 					mxbuf.xdp.data_hard_start;
842 				va = mxbuf.xdp.data;
843 			}
844 
845 			switch (act) {
846 			case XDP_PASS:
847 				break;
848 			case XDP_REDIRECT:
849 				if (likely(!xdp_do_redirect(dev, &mxbuf.xdp, xdp_prog))) {
850 					ring->xdp_redirect++;
851 					xdp_redir_flush = true;
852 					frags[0].page = NULL;
853 					goto next;
854 				}
855 				ring->xdp_redirect_fail++;
856 				trace_xdp_exception(dev, xdp_prog, act);
857 				goto xdp_drop_no_cnt;
858 			case XDP_TX:
859 				if (likely(!mlx4_en_xmit_frame(ring, frags, priv,
860 							length, cq_ring,
861 							&doorbell_pending))) {
862 					frags[0].page = NULL;
863 					goto next;
864 				}
865 				trace_xdp_exception(dev, xdp_prog, act);
866 				goto xdp_drop_no_cnt; /* Drop on xmit failure */
867 			default:
868 				bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
869 				fallthrough;
870 			case XDP_ABORTED:
871 				trace_xdp_exception(dev, xdp_prog, act);
872 				fallthrough;
873 			case XDP_DROP:
874 				ring->xdp_drop++;
875 xdp_drop_no_cnt:
876 				goto next;
877 			}
878 		}
879 
880 		ring->bytes += length;
881 		ring->packets++;
882 
883 		skb = napi_get_frags(&cq->napi);
884 		if (unlikely(!skb))
885 			goto next;
886 
887 		if (unlikely(ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL)) {
888 			u64 timestamp = mlx4_en_get_cqe_ts(cqe);
889 
890 			mlx4_en_fill_hwtstamps(priv->mdev, skb_hwtstamps(skb),
891 					       timestamp);
892 		}
893 		skb_record_rx_queue(skb, cq_ring);
894 
895 		if (likely(dev->features & NETIF_F_RXCSUM)) {
896 			/* TODO: For IP non TCP/UDP packets when csum complete is
897 			 * not an option (not supported or any other reason) we can
898 			 * actually check cqe IPOK status bit and report
899 			 * CHECKSUM_UNNECESSARY rather than CHECKSUM_NONE
900 			 */
901 			if ((cqe->status & cpu_to_be16(MLX4_CQE_STATUS_TCP |
902 						       MLX4_CQE_STATUS_UDP)) &&
903 			    (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
904 			    cqe->checksum == cpu_to_be16(0xffff)) {
905 				bool l2_tunnel;
906 
907 				l2_tunnel = (dev->hw_enc_features & NETIF_F_RXCSUM) &&
908 					(cqe->vlan_my_qpn & cpu_to_be32(MLX4_CQE_L2_TUNNEL));
909 				ip_summed = CHECKSUM_UNNECESSARY;
910 				hash_type = PKT_HASH_TYPE_L4;
911 				if (l2_tunnel)
912 					skb->csum_level = 1;
913 				ring->csum_ok++;
914 			} else {
915 				if (!(priv->flags & MLX4_EN_FLAG_RX_CSUM_NON_TCP_UDP &&
916 				      (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IP_ANY))))
917 					goto csum_none;
918 				if (check_csum(cqe, skb, va, dev->features))
919 					goto csum_none;
920 				ip_summed = CHECKSUM_COMPLETE;
921 				hash_type = PKT_HASH_TYPE_L3;
922 				ring->csum_complete++;
923 			}
924 		} else {
925 csum_none:
926 			ip_summed = CHECKSUM_NONE;
927 			hash_type = PKT_HASH_TYPE_L3;
928 			ring->csum_none++;
929 		}
930 		skb->ip_summed = ip_summed;
931 		if (dev->features & NETIF_F_RXHASH)
932 			skb_set_hash(skb,
933 				     be32_to_cpu(cqe->immed_rss_invalid),
934 				     hash_type);
935 
936 		if ((cqe->vlan_my_qpn &
937 		     cpu_to_be32(MLX4_CQE_CVLAN_PRESENT_MASK)) &&
938 		    (dev->features & NETIF_F_HW_VLAN_CTAG_RX))
939 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
940 					       be16_to_cpu(cqe->sl_vid));
941 		else if ((cqe->vlan_my_qpn &
942 			  cpu_to_be32(MLX4_CQE_SVLAN_PRESENT_MASK)) &&
943 			 (dev->features & NETIF_F_HW_VLAN_STAG_RX))
944 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021AD),
945 					       be16_to_cpu(cqe->sl_vid));
946 
947 		nr = mlx4_en_complete_rx_desc(priv, frags, skb, length);
948 		if (likely(nr)) {
949 			skb_shinfo(skb)->nr_frags = nr;
950 			skb->len = length;
951 			skb->data_len = length;
952 			napi_gro_frags(&cq->napi);
953 		} else {
954 			__vlan_hwaccel_clear_tag(skb);
955 			skb_clear_hash(skb);
956 		}
957 next:
958 		++cq->mcq.cons_index;
959 		index = (cq->mcq.cons_index) & ring->size_mask;
960 		cqe = mlx4_en_get_cqe(cq->buf, index, priv->cqe_size) + factor;
961 		if (unlikely(++polled == budget))
962 			break;
963 	}
964 
965 	if (xdp_redir_flush)
966 		xdp_do_flush();
967 
968 	if (likely(polled)) {
969 		if (doorbell_pending) {
970 			priv->tx_cq[TX_XDP][cq_ring]->xdp_busy = true;
971 			mlx4_en_xmit_doorbell(priv->tx_ring[TX_XDP][cq_ring]);
972 		}
973 
974 		mlx4_cq_set_ci(&cq->mcq);
975 		wmb(); /* ensure HW sees CQ consumer before we post new buffers */
976 		ring->cons = cq->mcq.cons_index;
977 	}
978 
979 	mlx4_en_refill_rx_buffers(priv, ring);
980 
981 	return polled;
982 }
983 
984 
985 void mlx4_en_rx_irq(struct mlx4_cq *mcq)
986 {
987 	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
988 	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
989 
990 	if (likely(priv->port_up))
991 		napi_schedule_irqoff(&cq->napi);
992 	else
993 		mlx4_en_arm_cq(priv, cq);
994 }
995 
996 /* Rx CQ polling - called by NAPI */
997 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget)
998 {
999 	struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
1000 	struct net_device *dev = cq->dev;
1001 	struct mlx4_en_priv *priv = netdev_priv(dev);
1002 	struct mlx4_en_cq *xdp_tx_cq = NULL;
1003 	bool clean_complete = true;
1004 	int done;
1005 
1006 	if (!budget)
1007 		return 0;
1008 
1009 	if (priv->tx_ring_num[TX_XDP]) {
1010 		xdp_tx_cq = priv->tx_cq[TX_XDP][cq->ring];
1011 		if (xdp_tx_cq->xdp_busy) {
1012 			clean_complete = mlx4_en_process_tx_cq(dev, xdp_tx_cq,
1013 							       budget) < budget;
1014 			xdp_tx_cq->xdp_busy = !clean_complete;
1015 		}
1016 	}
1017 
1018 	done = mlx4_en_process_rx_cq(dev, cq, budget);
1019 
1020 	/* If we used up all the quota - we're probably not done yet... */
1021 	if (done == budget || !clean_complete) {
1022 		int cpu_curr;
1023 
1024 		/* in case we got here because of !clean_complete */
1025 		done = budget;
1026 
1027 		cpu_curr = smp_processor_id();
1028 
1029 		if (likely(cpumask_test_cpu(cpu_curr, cq->aff_mask)))
1030 			return budget;
1031 
1032 		/* Current cpu is not according to smp_irq_affinity -
1033 		 * probably affinity changed. Need to stop this NAPI
1034 		 * poll, and restart it on the right CPU.
1035 		 * Try to avoid returning a too small value (like 0),
1036 		 * to not fool net_rx_action() and its netdev_budget
1037 		 */
1038 		if (done)
1039 			done--;
1040 	}
1041 	/* Done for now */
1042 	if (likely(napi_complete_done(napi, done)))
1043 		mlx4_en_arm_cq(priv, cq);
1044 	return done;
1045 }
1046 
1047 void mlx4_en_calc_rx_buf(struct net_device *dev)
1048 {
1049 	struct mlx4_en_priv *priv = netdev_priv(dev);
1050 	int eff_mtu = MLX4_EN_EFF_MTU(dev->mtu);
1051 	int i = 0;
1052 
1053 	/* bpf requires buffers to be set up as 1 packet per page.
1054 	 * This only works when num_frags == 1.
1055 	 */
1056 	if (priv->tx_ring_num[TX_XDP]) {
1057 		priv->frag_info[0].frag_size = eff_mtu;
1058 		/* This will gain efficient xdp frame recycling at the
1059 		 * expense of more costly truesize accounting
1060 		 */
1061 		priv->frag_info[0].frag_stride = PAGE_SIZE;
1062 		priv->dma_dir = DMA_BIDIRECTIONAL;
1063 		priv->rx_headroom = XDP_PACKET_HEADROOM;
1064 		i = 1;
1065 	} else {
1066 		int frag_size_max = 2048, buf_size = 0;
1067 
1068 		/* should not happen, right ? */
1069 		if (eff_mtu > PAGE_SIZE + (MLX4_EN_MAX_RX_FRAGS - 1) * 2048)
1070 			frag_size_max = PAGE_SIZE;
1071 
1072 		while (buf_size < eff_mtu) {
1073 			int frag_stride, frag_size = eff_mtu - buf_size;
1074 			int pad, nb;
1075 
1076 			if (i < MLX4_EN_MAX_RX_FRAGS - 1)
1077 				frag_size = min(frag_size, frag_size_max);
1078 
1079 			priv->frag_info[i].frag_size = frag_size;
1080 			frag_stride = ALIGN(frag_size, SMP_CACHE_BYTES);
1081 			/* We can only pack 2 1536-bytes frames in on 4K page
1082 			 * Therefore, each frame would consume more bytes (truesize)
1083 			 */
1084 			nb = PAGE_SIZE / frag_stride;
1085 			pad = (PAGE_SIZE - nb * frag_stride) / nb;
1086 			pad &= ~(SMP_CACHE_BYTES - 1);
1087 			priv->frag_info[i].frag_stride = frag_stride + pad;
1088 
1089 			buf_size += frag_size;
1090 			i++;
1091 		}
1092 		priv->dma_dir = DMA_FROM_DEVICE;
1093 		priv->rx_headroom = 0;
1094 	}
1095 
1096 	priv->num_frags = i;
1097 	priv->rx_skb_size = eff_mtu;
1098 	priv->log_rx_info = ROUNDUP_LOG2(i * sizeof(struct mlx4_en_rx_alloc));
1099 
1100 	en_dbg(DRV, priv, "Rx buffer scatter-list (effective-mtu:%d num_frags:%d):\n",
1101 	       eff_mtu, priv->num_frags);
1102 	for (i = 0; i < priv->num_frags; i++) {
1103 		en_dbg(DRV,
1104 		       priv,
1105 		       "  frag:%d - size:%d stride:%d\n",
1106 		       i,
1107 		       priv->frag_info[i].frag_size,
1108 		       priv->frag_info[i].frag_stride);
1109 	}
1110 }
1111 
1112 /* RSS related functions */
1113 
1114 static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
1115 				 struct mlx4_en_rx_ring *ring,
1116 				 enum mlx4_qp_state *state,
1117 				 struct mlx4_qp *qp)
1118 {
1119 	struct mlx4_en_dev *mdev = priv->mdev;
1120 	struct mlx4_qp_context *context;
1121 	int err = 0;
1122 
1123 	context = kzalloc(sizeof(*context), GFP_KERNEL);
1124 	if (!context)
1125 		return -ENOMEM;
1126 
1127 	err = mlx4_qp_alloc(mdev->dev, qpn, qp);
1128 	if (err) {
1129 		en_err(priv, "Failed to allocate qp #%x\n", qpn);
1130 		goto out;
1131 	}
1132 	qp->event = mlx4_en_sqp_event;
1133 
1134 	mlx4_en_fill_qp_context(priv, ring->actual_size, ring->stride, 0, 0,
1135 				qpn, ring->cqn, -1, context);
1136 	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);
1137 
1138 	/* Cancel FCS removal if FW allows */
1139 	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
1140 		context->param3 |= cpu_to_be32(1 << 29);
1141 		if (priv->dev->features & NETIF_F_RXFCS)
1142 			ring->fcs_del = 0;
1143 		else
1144 			ring->fcs_del = ETH_FCS_LEN;
1145 	} else
1146 		ring->fcs_del = 0;
1147 
1148 	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
1149 	if (err) {
1150 		mlx4_qp_remove(mdev->dev, qp);
1151 		mlx4_qp_free(mdev->dev, qp);
1152 	}
1153 	mlx4_en_update_rx_prod_db(ring);
1154 out:
1155 	kfree(context);
1156 	return err;
1157 }
1158 
1159 int mlx4_en_create_drop_qp(struct mlx4_en_priv *priv)
1160 {
1161 	int err;
1162 	u32 qpn;
1163 
1164 	err = mlx4_qp_reserve_range(priv->mdev->dev, 1, 1, &qpn,
1165 				    MLX4_RESERVE_A0_QP,
1166 				    MLX4_RES_USAGE_DRIVER);
1167 	if (err) {
1168 		en_err(priv, "Failed reserving drop qpn\n");
1169 		return err;
1170 	}
1171 	err = mlx4_qp_alloc(priv->mdev->dev, qpn, &priv->drop_qp);
1172 	if (err) {
1173 		en_err(priv, "Failed allocating drop qp\n");
1174 		mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
1175 		return err;
1176 	}
1177 
1178 	return 0;
1179 }
1180 
1181 void mlx4_en_destroy_drop_qp(struct mlx4_en_priv *priv)
1182 {
1183 	u32 qpn;
1184 
1185 	qpn = priv->drop_qp.qpn;
1186 	mlx4_qp_remove(priv->mdev->dev, &priv->drop_qp);
1187 	mlx4_qp_free(priv->mdev->dev, &priv->drop_qp);
1188 	mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
1189 }
1190 
1191 /* Allocate rx qp's and configure them according to rss map */
1192 int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
1193 {
1194 	struct mlx4_en_dev *mdev = priv->mdev;
1195 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
1196 	struct mlx4_qp_context context;
1197 	struct mlx4_rss_context *rss_context;
1198 	int rss_rings;
1199 	void *ptr;
1200 	u8 rss_mask = (MLX4_RSS_IPV4 | MLX4_RSS_TCP_IPV4 | MLX4_RSS_IPV6 |
1201 			MLX4_RSS_TCP_IPV6);
1202 	int i, qpn;
1203 	int err = 0;
1204 	int good_qps = 0;
1205 	u8 flags;
1206 
1207 	en_dbg(DRV, priv, "Configuring rss steering\n");
1208 
1209 	flags = priv->rx_ring_num == 1 ? MLX4_RESERVE_A0_QP : 0;
1210 	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
1211 				    priv->rx_ring_num,
1212 				    &rss_map->base_qpn, flags,
1213 				    MLX4_RES_USAGE_DRIVER);
1214 	if (err) {
1215 		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
1216 		return err;
1217 	}
1218 
1219 	for (i = 0; i < priv->rx_ring_num; i++) {
1220 		qpn = rss_map->base_qpn + i;
1221 		err = mlx4_en_config_rss_qp(priv, qpn, priv->rx_ring[i],
1222 					    &rss_map->state[i],
1223 					    &rss_map->qps[i]);
1224 		if (err)
1225 			goto rss_err;
1226 
1227 		++good_qps;
1228 	}
1229 
1230 	if (priv->rx_ring_num == 1) {
1231 		rss_map->indir_qp = &rss_map->qps[0];
1232 		priv->base_qpn = rss_map->indir_qp->qpn;
1233 		en_info(priv, "Optimized Non-RSS steering\n");
1234 		return 0;
1235 	}
1236 
1237 	rss_map->indir_qp = kzalloc(sizeof(*rss_map->indir_qp), GFP_KERNEL);
1238 	if (!rss_map->indir_qp) {
1239 		err = -ENOMEM;
1240 		goto rss_err;
1241 	}
1242 
1243 	/* Configure RSS indirection qp */
1244 	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, rss_map->indir_qp);
1245 	if (err) {
1246 		en_err(priv, "Failed to allocate RSS indirection QP\n");
1247 		goto qp_alloc_err;
1248 	}
1249 
1250 	rss_map->indir_qp->event = mlx4_en_sqp_event;
1251 	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
1252 				priv->rx_ring[0]->cqn, -1, &context);
1253 
1254 	if (!priv->prof->rss_rings || priv->prof->rss_rings > priv->rx_ring_num)
1255 		rss_rings = priv->rx_ring_num;
1256 	else
1257 		rss_rings = priv->prof->rss_rings;
1258 
1259 	ptr = ((void *) &context) + offsetof(struct mlx4_qp_context, pri_path)
1260 					+ MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
1261 	rss_context = ptr;
1262 	rss_context->base_qpn = cpu_to_be32(ilog2(rss_rings) << 24 |
1263 					    (rss_map->base_qpn));
1264 	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
1265 	if (priv->mdev->profile.udp_rss) {
1266 		rss_mask |=  MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6;
1267 		rss_context->base_qpn_udp = rss_context->default_qpn;
1268 	}
1269 
1270 	if (mdev->dev->caps.tunnel_offload_mode == MLX4_TUNNEL_OFFLOAD_MODE_VXLAN) {
1271 		en_info(priv, "Setting RSS context tunnel type to RSS on inner headers\n");
1272 		rss_mask |= MLX4_RSS_BY_INNER_HEADERS;
1273 	}
1274 
1275 	rss_context->flags = rss_mask;
1276 	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
1277 	if (priv->rss_hash_fn == ETH_RSS_HASH_XOR) {
1278 		rss_context->hash_fn = MLX4_RSS_HASH_XOR;
1279 	} else if (priv->rss_hash_fn == ETH_RSS_HASH_TOP) {
1280 		rss_context->hash_fn = MLX4_RSS_HASH_TOP;
1281 		memcpy(rss_context->rss_key, priv->rss_key,
1282 		       MLX4_EN_RSS_KEY_SIZE);
1283 	} else {
1284 		en_err(priv, "Unknown RSS hash function requested\n");
1285 		err = -EINVAL;
1286 		goto indir_err;
1287 	}
1288 
1289 	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
1290 			       rss_map->indir_qp, &rss_map->indir_state);
1291 	if (err)
1292 		goto indir_err;
1293 
1294 	return 0;
1295 
1296 indir_err:
1297 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1298 		       MLX4_QP_STATE_RST, NULL, 0, 0, rss_map->indir_qp);
1299 	mlx4_qp_remove(mdev->dev, rss_map->indir_qp);
1300 	mlx4_qp_free(mdev->dev, rss_map->indir_qp);
1301 qp_alloc_err:
1302 	kfree(rss_map->indir_qp);
1303 	rss_map->indir_qp = NULL;
1304 rss_err:
1305 	for (i = 0; i < good_qps; i++) {
1306 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1307 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1308 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1309 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1310 	}
1311 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1312 	return err;
1313 }
1314 
1315 void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
1316 {
1317 	struct mlx4_en_dev *mdev = priv->mdev;
1318 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
1319 	int i;
1320 
1321 	if (priv->rx_ring_num > 1) {
1322 		mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1323 			       MLX4_QP_STATE_RST, NULL, 0, 0,
1324 			       rss_map->indir_qp);
1325 		mlx4_qp_remove(mdev->dev, rss_map->indir_qp);
1326 		mlx4_qp_free(mdev->dev, rss_map->indir_qp);
1327 		kfree(rss_map->indir_qp);
1328 		rss_map->indir_qp = NULL;
1329 	}
1330 
1331 	for (i = 0; i < priv->rx_ring_num; i++) {
1332 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1333 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1334 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1335 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1336 	}
1337 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1338 }
1339