xref: /linux/drivers/net/ethernet/mellanox/mlx4/en_rx.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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/mlx4/cq.h>
35 #include <linux/slab.h>
36 #include <linux/mlx4/qp.h>
37 #include <linux/skbuff.h>
38 #include <linux/if_ether.h>
39 #include <linux/if_vlan.h>
40 #include <linux/vmalloc.h>
41 
42 #include "mlx4_en.h"
43 
44 
45 static int mlx4_en_alloc_frag(struct mlx4_en_priv *priv,
46 			      struct mlx4_en_rx_desc *rx_desc,
47 			      struct page_frag *skb_frags,
48 			      struct mlx4_en_rx_alloc *ring_alloc,
49 			      int i)
50 {
51 	struct mlx4_en_dev *mdev = priv->mdev;
52 	struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
53 	struct mlx4_en_rx_alloc *page_alloc = &ring_alloc[i];
54 	struct page *page;
55 	dma_addr_t dma;
56 
57 	if (page_alloc->offset == frag_info->last_offset) {
58 		/* Allocate new page */
59 		page = alloc_pages(GFP_ATOMIC | __GFP_COMP, MLX4_EN_ALLOC_ORDER);
60 		if (!page)
61 			return -ENOMEM;
62 
63 		skb_frags[i].page = page_alloc->page;
64 		skb_frags[i].offset = page_alloc->offset;
65 		page_alloc->page = page;
66 		page_alloc->offset = frag_info->frag_align;
67 	} else {
68 		page = page_alloc->page;
69 		get_page(page);
70 
71 		skb_frags[i].page = page;
72 		skb_frags[i].offset = page_alloc->offset;
73 		page_alloc->offset += frag_info->frag_stride;
74 	}
75 	dma = pci_map_single(mdev->pdev, page_address(skb_frags[i].page) +
76 			     skb_frags[i].offset, frag_info->frag_size,
77 			     PCI_DMA_FROMDEVICE);
78 	rx_desc->data[i].addr = cpu_to_be64(dma);
79 	return 0;
80 }
81 
82 static int mlx4_en_init_allocator(struct mlx4_en_priv *priv,
83 				  struct mlx4_en_rx_ring *ring)
84 {
85 	struct mlx4_en_rx_alloc *page_alloc;
86 	int i;
87 
88 	for (i = 0; i < priv->num_frags; i++) {
89 		page_alloc = &ring->page_alloc[i];
90 		page_alloc->page = alloc_pages(GFP_ATOMIC | __GFP_COMP,
91 					       MLX4_EN_ALLOC_ORDER);
92 		if (!page_alloc->page)
93 			goto out;
94 
95 		page_alloc->offset = priv->frag_info[i].frag_align;
96 		en_dbg(DRV, priv, "Initialized allocator:%d with page:%p\n",
97 		       i, page_alloc->page);
98 	}
99 	return 0;
100 
101 out:
102 	while (i--) {
103 		page_alloc = &ring->page_alloc[i];
104 		put_page(page_alloc->page);
105 		page_alloc->page = NULL;
106 	}
107 	return -ENOMEM;
108 }
109 
110 static void mlx4_en_destroy_allocator(struct mlx4_en_priv *priv,
111 				      struct mlx4_en_rx_ring *ring)
112 {
113 	struct mlx4_en_rx_alloc *page_alloc;
114 	int i;
115 
116 	for (i = 0; i < priv->num_frags; i++) {
117 		page_alloc = &ring->page_alloc[i];
118 		en_dbg(DRV, priv, "Freeing allocator:%d count:%d\n",
119 		       i, page_count(page_alloc->page));
120 
121 		put_page(page_alloc->page);
122 		page_alloc->page = NULL;
123 	}
124 }
125 
126 
127 static void mlx4_en_init_rx_desc(struct mlx4_en_priv *priv,
128 				 struct mlx4_en_rx_ring *ring, int index)
129 {
130 	struct mlx4_en_rx_desc *rx_desc = ring->buf + ring->stride * index;
131 	struct skb_frag_struct *skb_frags = ring->rx_info +
132 					    (index << priv->log_rx_info);
133 	int possible_frags;
134 	int i;
135 
136 	/* Set size and memtype fields */
137 	for (i = 0; i < priv->num_frags; i++) {
138 		skb_frag_size_set(&skb_frags[i], priv->frag_info[i].frag_size);
139 		rx_desc->data[i].byte_count =
140 			cpu_to_be32(priv->frag_info[i].frag_size);
141 		rx_desc->data[i].lkey = cpu_to_be32(priv->mdev->mr.key);
142 	}
143 
144 	/* If the number of used fragments does not fill up the ring stride,
145 	 * remaining (unused) fragments must be padded with null address/size
146 	 * and a special memory key */
147 	possible_frags = (ring->stride - sizeof(struct mlx4_en_rx_desc)) / DS_SIZE;
148 	for (i = priv->num_frags; i < possible_frags; i++) {
149 		rx_desc->data[i].byte_count = 0;
150 		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
151 		rx_desc->data[i].addr = 0;
152 	}
153 }
154 
155 
156 static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
157 				   struct mlx4_en_rx_ring *ring, int index)
158 {
159 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index * ring->stride);
160 	struct page_frag *skb_frags = ring->rx_info +
161 				      (index << priv->log_rx_info);
162 	int i;
163 
164 	for (i = 0; i < priv->num_frags; i++)
165 		if (mlx4_en_alloc_frag(priv, rx_desc, skb_frags, ring->page_alloc, i))
166 			goto err;
167 
168 	return 0;
169 
170 err:
171 	while (i--)
172 		put_page(skb_frags[i].page);
173 	return -ENOMEM;
174 }
175 
176 static inline void mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
177 {
178 	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
179 }
180 
181 static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv,
182 				 struct mlx4_en_rx_ring *ring,
183 				 int index)
184 {
185 	struct mlx4_en_dev *mdev = priv->mdev;
186 	struct page_frag *skb_frags;
187 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index << ring->log_stride);
188 	dma_addr_t dma;
189 	int nr;
190 
191 	skb_frags = ring->rx_info + (index << priv->log_rx_info);
192 	for (nr = 0; nr < priv->num_frags; nr++) {
193 		en_dbg(DRV, priv, "Freeing fragment:%d\n", nr);
194 		dma = be64_to_cpu(rx_desc->data[nr].addr);
195 
196 		en_dbg(DRV, priv, "Unmapping buffer at dma:0x%llx\n", (u64) dma);
197 		pci_unmap_single(mdev->pdev, dma, skb_frags[nr].size,
198 				 PCI_DMA_FROMDEVICE);
199 		put_page(skb_frags[nr].page);
200 	}
201 }
202 
203 static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
204 {
205 	struct mlx4_en_rx_ring *ring;
206 	int ring_ind;
207 	int buf_ind;
208 	int new_size;
209 
210 	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
211 		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
212 			ring = &priv->rx_ring[ring_ind];
213 
214 			if (mlx4_en_prepare_rx_desc(priv, ring,
215 						    ring->actual_size)) {
216 				if (ring->actual_size < MLX4_EN_MIN_RX_SIZE) {
217 					en_err(priv, "Failed to allocate "
218 						     "enough rx buffers\n");
219 					return -ENOMEM;
220 				} else {
221 					new_size = rounddown_pow_of_two(ring->actual_size);
222 					en_warn(priv, "Only %d buffers allocated "
223 						      "reducing ring size to %d",
224 						ring->actual_size, new_size);
225 					goto reduce_rings;
226 				}
227 			}
228 			ring->actual_size++;
229 			ring->prod++;
230 		}
231 	}
232 	return 0;
233 
234 reduce_rings:
235 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
236 		ring = &priv->rx_ring[ring_ind];
237 		while (ring->actual_size > new_size) {
238 			ring->actual_size--;
239 			ring->prod--;
240 			mlx4_en_free_rx_desc(priv, ring, ring->actual_size);
241 		}
242 	}
243 
244 	return 0;
245 }
246 
247 static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
248 				struct mlx4_en_rx_ring *ring)
249 {
250 	int index;
251 
252 	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
253 	       ring->cons, ring->prod);
254 
255 	/* Unmap and free Rx buffers */
256 	BUG_ON((u32) (ring->prod - ring->cons) > ring->actual_size);
257 	while (ring->cons != ring->prod) {
258 		index = ring->cons & ring->size_mask;
259 		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
260 		mlx4_en_free_rx_desc(priv, ring, index);
261 		++ring->cons;
262 	}
263 }
264 
265 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
266 			   struct mlx4_en_rx_ring *ring, u32 size, u16 stride)
267 {
268 	struct mlx4_en_dev *mdev = priv->mdev;
269 	int err;
270 	int tmp;
271 
272 
273 	ring->prod = 0;
274 	ring->cons = 0;
275 	ring->size = size;
276 	ring->size_mask = size - 1;
277 	ring->stride = stride;
278 	ring->log_stride = ffs(ring->stride) - 1;
279 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
280 
281 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
282 					sizeof(struct skb_frag_struct));
283 	ring->rx_info = vmalloc(tmp);
284 	if (!ring->rx_info) {
285 		en_err(priv, "Failed allocating rx_info ring\n");
286 		return -ENOMEM;
287 	}
288 	en_dbg(DRV, priv, "Allocated rx_info ring at addr:%p size:%d\n",
289 		 ring->rx_info, tmp);
290 
291 	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres,
292 				 ring->buf_size, 2 * PAGE_SIZE);
293 	if (err)
294 		goto err_ring;
295 
296 	err = mlx4_en_map_buffer(&ring->wqres.buf);
297 	if (err) {
298 		en_err(priv, "Failed to map RX buffer\n");
299 		goto err_hwq;
300 	}
301 	ring->buf = ring->wqres.buf.direct.buf;
302 
303 	return 0;
304 
305 err_hwq:
306 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
307 err_ring:
308 	vfree(ring->rx_info);
309 	ring->rx_info = NULL;
310 	return err;
311 }
312 
313 int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
314 {
315 	struct mlx4_en_rx_ring *ring;
316 	int i;
317 	int ring_ind;
318 	int err;
319 	int stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
320 					DS_SIZE * priv->num_frags);
321 
322 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
323 		ring = &priv->rx_ring[ring_ind];
324 
325 		ring->prod = 0;
326 		ring->cons = 0;
327 		ring->actual_size = 0;
328 		ring->cqn = priv->rx_cq[ring_ind].mcq.cqn;
329 
330 		ring->stride = stride;
331 		if (ring->stride <= TXBB_SIZE)
332 			ring->buf += TXBB_SIZE;
333 
334 		ring->log_stride = ffs(ring->stride) - 1;
335 		ring->buf_size = ring->size * ring->stride;
336 
337 		memset(ring->buf, 0, ring->buf_size);
338 		mlx4_en_update_rx_prod_db(ring);
339 
340 		/* Initailize all descriptors */
341 		for (i = 0; i < ring->size; i++)
342 			mlx4_en_init_rx_desc(priv, ring, i);
343 
344 		/* Initialize page allocators */
345 		err = mlx4_en_init_allocator(priv, ring);
346 		if (err) {
347 			en_err(priv, "Failed initializing ring allocator\n");
348 			if (ring->stride <= TXBB_SIZE)
349 				ring->buf -= TXBB_SIZE;
350 			ring_ind--;
351 			goto err_allocator;
352 		}
353 	}
354 	err = mlx4_en_fill_rx_buffers(priv);
355 	if (err)
356 		goto err_buffers;
357 
358 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
359 		ring = &priv->rx_ring[ring_ind];
360 
361 		ring->size_mask = ring->actual_size - 1;
362 		mlx4_en_update_rx_prod_db(ring);
363 	}
364 
365 	return 0;
366 
367 err_buffers:
368 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
369 		mlx4_en_free_rx_buf(priv, &priv->rx_ring[ring_ind]);
370 
371 	ring_ind = priv->rx_ring_num - 1;
372 err_allocator:
373 	while (ring_ind >= 0) {
374 		if (priv->rx_ring[ring_ind].stride <= TXBB_SIZE)
375 			priv->rx_ring[ring_ind].buf -= TXBB_SIZE;
376 		mlx4_en_destroy_allocator(priv, &priv->rx_ring[ring_ind]);
377 		ring_ind--;
378 	}
379 	return err;
380 }
381 
382 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
383 			     struct mlx4_en_rx_ring *ring)
384 {
385 	struct mlx4_en_dev *mdev = priv->mdev;
386 
387 	mlx4_en_unmap_buffer(&ring->wqres.buf);
388 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size + TXBB_SIZE);
389 	vfree(ring->rx_info);
390 	ring->rx_info = NULL;
391 }
392 
393 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
394 				struct mlx4_en_rx_ring *ring)
395 {
396 	mlx4_en_free_rx_buf(priv, ring);
397 	if (ring->stride <= TXBB_SIZE)
398 		ring->buf -= TXBB_SIZE;
399 	mlx4_en_destroy_allocator(priv, ring);
400 }
401 
402 
403 /* Unmap a completed descriptor and free unused pages */
404 static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
405 				    struct mlx4_en_rx_desc *rx_desc,
406 				    struct page_frag *skb_frags,
407 				    struct sk_buff *skb,
408 				    struct mlx4_en_rx_alloc *page_alloc,
409 				    int length)
410 {
411 	struct skb_frag_struct *skb_frags_rx = skb_shinfo(skb)->frags;
412 	struct mlx4_en_dev *mdev = priv->mdev;
413 	struct mlx4_en_frag_info *frag_info;
414 	int nr;
415 	dma_addr_t dma;
416 
417 	/* Collect used fragments while replacing them in the HW descirptors */
418 	for (nr = 0; nr < priv->num_frags; nr++) {
419 		frag_info = &priv->frag_info[nr];
420 		if (length <= frag_info->frag_prefix_size)
421 			break;
422 
423 		/* Save page reference in skb */
424 		__skb_frag_set_page(&skb_frags_rx[nr], skb_frags[nr].page);
425 		skb_frag_size_set(&skb_frags_rx[nr], skb_frags[nr].size);
426 		skb_frags_rx[nr].page_offset = skb_frags[nr].offset;
427 		skb->truesize += frag_info->frag_stride;
428 		dma = be64_to_cpu(rx_desc->data[nr].addr);
429 
430 		/* Allocate a replacement page */
431 		if (mlx4_en_alloc_frag(priv, rx_desc, skb_frags, page_alloc, nr))
432 			goto fail;
433 
434 		/* Unmap buffer */
435 		pci_unmap_single(mdev->pdev, dma, skb_frag_size(&skb_frags_rx[nr]),
436 				 PCI_DMA_FROMDEVICE);
437 	}
438 	/* Adjust size of last fragment to match actual length */
439 	if (nr > 0)
440 		skb_frag_size_set(&skb_frags_rx[nr - 1],
441 			length - priv->frag_info[nr - 1].frag_prefix_size);
442 	return nr;
443 
444 fail:
445 	/* Drop all accumulated fragments (which have already been replaced in
446 	 * the descriptor) of this packet; remaining fragments are reused... */
447 	while (nr > 0) {
448 		nr--;
449 		__skb_frag_unref(&skb_frags_rx[nr]);
450 	}
451 	return 0;
452 }
453 
454 
455 static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv,
456 				      struct mlx4_en_rx_desc *rx_desc,
457 				      struct page_frag *skb_frags,
458 				      struct mlx4_en_rx_alloc *page_alloc,
459 				      unsigned int length)
460 {
461 	struct mlx4_en_dev *mdev = priv->mdev;
462 	struct sk_buff *skb;
463 	void *va;
464 	int used_frags;
465 	dma_addr_t dma;
466 
467 	skb = dev_alloc_skb(SMALL_PACKET_SIZE + NET_IP_ALIGN);
468 	if (!skb) {
469 		en_dbg(RX_ERR, priv, "Failed allocating skb\n");
470 		return NULL;
471 	}
472 	skb->dev = priv->dev;
473 	skb_reserve(skb, NET_IP_ALIGN);
474 	skb->len = length;
475 
476 	/* Get pointer to first fragment so we could copy the headers into the
477 	 * (linear part of the) skb */
478 	va = page_address(skb_frags[0].page) + skb_frags[0].offset;
479 
480 	if (length <= SMALL_PACKET_SIZE) {
481 		/* We are copying all relevant data to the skb - temporarily
482 		 * synch buffers for the copy */
483 		dma = be64_to_cpu(rx_desc->data[0].addr);
484 		dma_sync_single_for_cpu(&mdev->pdev->dev, dma, length,
485 					DMA_FROM_DEVICE);
486 		skb_copy_to_linear_data(skb, va, length);
487 		dma_sync_single_for_device(&mdev->pdev->dev, dma, length,
488 					   DMA_FROM_DEVICE);
489 		skb->tail += length;
490 	} else {
491 
492 		/* Move relevant fragments to skb */
493 		used_frags = mlx4_en_complete_rx_desc(priv, rx_desc, skb_frags,
494 						      skb, page_alloc, length);
495 		if (unlikely(!used_frags)) {
496 			kfree_skb(skb);
497 			return NULL;
498 		}
499 		skb_shinfo(skb)->nr_frags = used_frags;
500 
501 		/* Copy headers into the skb linear buffer */
502 		memcpy(skb->data, va, HEADER_COPY_SIZE);
503 		skb->tail += HEADER_COPY_SIZE;
504 
505 		/* Skip headers in first fragment */
506 		skb_shinfo(skb)->frags[0].page_offset += HEADER_COPY_SIZE;
507 
508 		/* Adjust size of first fragment */
509 		skb_frag_size_sub(&skb_shinfo(skb)->frags[0], HEADER_COPY_SIZE);
510 		skb->data_len = length - HEADER_COPY_SIZE;
511 	}
512 	return skb;
513 }
514 
515 static void validate_loopback(struct mlx4_en_priv *priv, struct sk_buff *skb)
516 {
517 	int i;
518 	int offset = ETH_HLEN;
519 
520 	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++, offset++) {
521 		if (*(skb->data + offset) != (unsigned char) (i & 0xff))
522 			goto out_loopback;
523 	}
524 	/* Loopback found */
525 	priv->loopback_ok = 1;
526 
527 out_loopback:
528 	dev_kfree_skb_any(skb);
529 }
530 
531 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
532 {
533 	struct mlx4_en_priv *priv = netdev_priv(dev);
534 	struct mlx4_cqe *cqe;
535 	struct mlx4_en_rx_ring *ring = &priv->rx_ring[cq->ring];
536 	struct page_frag *skb_frags;
537 	struct mlx4_en_rx_desc *rx_desc;
538 	struct sk_buff *skb;
539 	int index;
540 	int nr;
541 	unsigned int length;
542 	int polled = 0;
543 	int ip_summed;
544 
545 	if (!priv->port_up)
546 		return 0;
547 
548 	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
549 	 * descriptor offset can be deduced from the CQE index instead of
550 	 * reading 'cqe->index' */
551 	index = cq->mcq.cons_index & ring->size_mask;
552 	cqe = &cq->buf[index];
553 
554 	/* Process all completed CQEs */
555 	while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
556 		    cq->mcq.cons_index & cq->size)) {
557 
558 		skb_frags = ring->rx_info + (index << priv->log_rx_info);
559 		rx_desc = ring->buf + (index << ring->log_stride);
560 
561 		/*
562 		 * make sure we read the CQE after we read the ownership bit
563 		 */
564 		rmb();
565 
566 		/* Drop packet on bad receive or bad checksum */
567 		if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
568 						MLX4_CQE_OPCODE_ERROR)) {
569 			en_err(priv, "CQE completed in error - vendor "
570 				  "syndrom:%d syndrom:%d\n",
571 				  ((struct mlx4_err_cqe *) cqe)->vendor_err_syndrome,
572 				  ((struct mlx4_err_cqe *) cqe)->syndrome);
573 			goto next;
574 		}
575 		if (unlikely(cqe->badfcs_enc & MLX4_CQE_BAD_FCS)) {
576 			en_dbg(RX_ERR, priv, "Accepted frame with bad FCS\n");
577 			goto next;
578 		}
579 
580 		/*
581 		 * Packet is OK - process it.
582 		 */
583 		length = be32_to_cpu(cqe->byte_cnt);
584 		ring->bytes += length;
585 		ring->packets++;
586 
587 		if (likely(dev->features & NETIF_F_RXCSUM)) {
588 			if ((cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
589 			    (cqe->checksum == cpu_to_be16(0xffff))) {
590 				ring->csum_ok++;
591 				/* This packet is eligible for LRO if it is:
592 				 * - DIX Ethernet (type interpretation)
593 				 * - TCP/IP (v4)
594 				 * - without IP options
595 				 * - not an IP fragment */
596 				if (dev->features & NETIF_F_GRO) {
597 					struct sk_buff *gro_skb = napi_get_frags(&cq->napi);
598 					if (!gro_skb)
599 						goto next;
600 
601 					nr = mlx4_en_complete_rx_desc(
602 						priv, rx_desc,
603 						skb_frags, gro_skb,
604 						ring->page_alloc, length);
605 					if (!nr)
606 						goto next;
607 
608 					skb_shinfo(gro_skb)->nr_frags = nr;
609 					gro_skb->len = length;
610 					gro_skb->data_len = length;
611 					gro_skb->ip_summed = CHECKSUM_UNNECESSARY;
612 
613 					if (cqe->vlan_my_qpn &
614 					    cpu_to_be32(MLX4_CQE_VLAN_PRESENT_MASK)) {
615 						u16 vid = be16_to_cpu(cqe->sl_vid);
616 
617 						__vlan_hwaccel_put_tag(gro_skb, vid);
618 					}
619 
620 					if (dev->features & NETIF_F_RXHASH)
621 						gro_skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
622 
623 					skb_record_rx_queue(gro_skb, cq->ring);
624 					napi_gro_frags(&cq->napi);
625 
626 					goto next;
627 				}
628 
629 				/* LRO not possible, complete processing here */
630 				ip_summed = CHECKSUM_UNNECESSARY;
631 			} else {
632 				ip_summed = CHECKSUM_NONE;
633 				ring->csum_none++;
634 			}
635 		} else {
636 			ip_summed = CHECKSUM_NONE;
637 			ring->csum_none++;
638 		}
639 
640 		skb = mlx4_en_rx_skb(priv, rx_desc, skb_frags,
641 				     ring->page_alloc, length);
642 		if (!skb) {
643 			priv->stats.rx_dropped++;
644 			goto next;
645 		}
646 
647                 if (unlikely(priv->validate_loopback)) {
648 			validate_loopback(priv, skb);
649 			goto next;
650 		}
651 
652 		skb->ip_summed = ip_summed;
653 		skb->protocol = eth_type_trans(skb, dev);
654 		skb_record_rx_queue(skb, cq->ring);
655 
656 		if (dev->features & NETIF_F_RXHASH)
657 			skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
658 
659 		if (be32_to_cpu(cqe->vlan_my_qpn) &
660 		    MLX4_CQE_VLAN_PRESENT_MASK)
661 			__vlan_hwaccel_put_tag(skb, be16_to_cpu(cqe->sl_vid));
662 
663 		/* Push it up the stack */
664 		netif_receive_skb(skb);
665 
666 next:
667 		++cq->mcq.cons_index;
668 		index = (cq->mcq.cons_index) & ring->size_mask;
669 		cqe = &cq->buf[index];
670 		if (++polled == budget) {
671 			/* We are here because we reached the NAPI budget -
672 			 * flush only pending LRO sessions */
673 			goto out;
674 		}
675 	}
676 
677 out:
678 	AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
679 	mlx4_cq_set_ci(&cq->mcq);
680 	wmb(); /* ensure HW sees CQ consumer before we post new buffers */
681 	ring->cons = cq->mcq.cons_index;
682 	ring->prod += polled; /* Polled descriptors were realocated in place */
683 	mlx4_en_update_rx_prod_db(ring);
684 	return polled;
685 }
686 
687 
688 void mlx4_en_rx_irq(struct mlx4_cq *mcq)
689 {
690 	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
691 	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
692 
693 	if (priv->port_up)
694 		napi_schedule(&cq->napi);
695 	else
696 		mlx4_en_arm_cq(priv, cq);
697 }
698 
699 /* Rx CQ polling - called by NAPI */
700 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget)
701 {
702 	struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
703 	struct net_device *dev = cq->dev;
704 	struct mlx4_en_priv *priv = netdev_priv(dev);
705 	int done;
706 
707 	done = mlx4_en_process_rx_cq(dev, cq, budget);
708 
709 	/* If we used up all the quota - we're probably not done yet... */
710 	if (done == budget)
711 		INC_PERF_COUNTER(priv->pstats.napi_quota);
712 	else {
713 		/* Done for now */
714 		napi_complete(napi);
715 		mlx4_en_arm_cq(priv, cq);
716 	}
717 	return done;
718 }
719 
720 
721 /* Calculate the last offset position that accommodates a full fragment
722  * (assuming fagment size = stride-align) */
723 static int mlx4_en_last_alloc_offset(struct mlx4_en_priv *priv, u16 stride, u16 align)
724 {
725 	u16 res = MLX4_EN_ALLOC_SIZE % stride;
726 	u16 offset = MLX4_EN_ALLOC_SIZE - stride - res + align;
727 
728 	en_dbg(DRV, priv, "Calculated last offset for stride:%d align:%d "
729 			    "res:%d offset:%d\n", stride, align, res, offset);
730 	return offset;
731 }
732 
733 
734 static int frag_sizes[] = {
735 	FRAG_SZ0,
736 	FRAG_SZ1,
737 	FRAG_SZ2,
738 	FRAG_SZ3
739 };
740 
741 void mlx4_en_calc_rx_buf(struct net_device *dev)
742 {
743 	struct mlx4_en_priv *priv = netdev_priv(dev);
744 	int eff_mtu = dev->mtu + ETH_HLEN + VLAN_HLEN + ETH_LLC_SNAP_SIZE;
745 	int buf_size = 0;
746 	int i = 0;
747 
748 	while (buf_size < eff_mtu) {
749 		priv->frag_info[i].frag_size =
750 			(eff_mtu > buf_size + frag_sizes[i]) ?
751 				frag_sizes[i] : eff_mtu - buf_size;
752 		priv->frag_info[i].frag_prefix_size = buf_size;
753 		if (!i)	{
754 			priv->frag_info[i].frag_align = NET_IP_ALIGN;
755 			priv->frag_info[i].frag_stride =
756 				ALIGN(frag_sizes[i] + NET_IP_ALIGN, SMP_CACHE_BYTES);
757 		} else {
758 			priv->frag_info[i].frag_align = 0;
759 			priv->frag_info[i].frag_stride =
760 				ALIGN(frag_sizes[i], SMP_CACHE_BYTES);
761 		}
762 		priv->frag_info[i].last_offset = mlx4_en_last_alloc_offset(
763 						priv, priv->frag_info[i].frag_stride,
764 						priv->frag_info[i].frag_align);
765 		buf_size += priv->frag_info[i].frag_size;
766 		i++;
767 	}
768 
769 	priv->num_frags = i;
770 	priv->rx_skb_size = eff_mtu;
771 	priv->log_rx_info = ROUNDUP_LOG2(i * sizeof(struct skb_frag_struct));
772 
773 	en_dbg(DRV, priv, "Rx buffer scatter-list (effective-mtu:%d "
774 		  "num_frags:%d):\n", eff_mtu, priv->num_frags);
775 	for (i = 0; i < priv->num_frags; i++) {
776 		en_dbg(DRV, priv, "  frag:%d - size:%d prefix:%d align:%d "
777 				"stride:%d last_offset:%d\n", i,
778 				priv->frag_info[i].frag_size,
779 				priv->frag_info[i].frag_prefix_size,
780 				priv->frag_info[i].frag_align,
781 				priv->frag_info[i].frag_stride,
782 				priv->frag_info[i].last_offset);
783 	}
784 }
785 
786 /* RSS related functions */
787 
788 static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
789 				 struct mlx4_en_rx_ring *ring,
790 				 enum mlx4_qp_state *state,
791 				 struct mlx4_qp *qp)
792 {
793 	struct mlx4_en_dev *mdev = priv->mdev;
794 	struct mlx4_qp_context *context;
795 	int err = 0;
796 
797 	context = kmalloc(sizeof *context , GFP_KERNEL);
798 	if (!context) {
799 		en_err(priv, "Failed to allocate qp context\n");
800 		return -ENOMEM;
801 	}
802 
803 	err = mlx4_qp_alloc(mdev->dev, qpn, qp);
804 	if (err) {
805 		en_err(priv, "Failed to allocate qp #%x\n", qpn);
806 		goto out;
807 	}
808 	qp->event = mlx4_en_sqp_event;
809 
810 	memset(context, 0, sizeof *context);
811 	mlx4_en_fill_qp_context(priv, ring->actual_size, ring->stride, 0, 0,
812 				qpn, ring->cqn, context);
813 	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);
814 
815 	/* Cancel FCS removal if FW allows */
816 	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP)
817 		context->param3 |= cpu_to_be32(1 << 29);
818 
819 	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
820 	if (err) {
821 		mlx4_qp_remove(mdev->dev, qp);
822 		mlx4_qp_free(mdev->dev, qp);
823 	}
824 	mlx4_en_update_rx_prod_db(ring);
825 out:
826 	kfree(context);
827 	return err;
828 }
829 
830 /* Allocate rx qp's and configure them according to rss map */
831 int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
832 {
833 	struct mlx4_en_dev *mdev = priv->mdev;
834 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
835 	struct mlx4_qp_context context;
836 	struct mlx4_en_rss_context *rss_context;
837 	void *ptr;
838 	u8 rss_mask = 0x3f;
839 	int i, qpn;
840 	int err = 0;
841 	int good_qps = 0;
842 	static const u32 rsskey[10] = { 0xD181C62C, 0xF7F4DB5B, 0x1983A2FC,
843 				0x943E1ADB, 0xD9389E6B, 0xD1039C2C, 0xA74499AD,
844 				0x593D56D9, 0xF3253C06, 0x2ADC1FFC};
845 
846 	en_dbg(DRV, priv, "Configuring rss steering\n");
847 	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
848 				    priv->rx_ring_num,
849 				    &rss_map->base_qpn);
850 	if (err) {
851 		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
852 		return err;
853 	}
854 
855 	for (i = 0; i < priv->rx_ring_num; i++) {
856 		qpn = rss_map->base_qpn + i;
857 		err = mlx4_en_config_rss_qp(priv, qpn, &priv->rx_ring[i],
858 					    &rss_map->state[i],
859 					    &rss_map->qps[i]);
860 		if (err)
861 			goto rss_err;
862 
863 		++good_qps;
864 	}
865 
866 	/* Configure RSS indirection qp */
867 	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp);
868 	if (err) {
869 		en_err(priv, "Failed to allocate RSS indirection QP\n");
870 		goto rss_err;
871 	}
872 	rss_map->indir_qp.event = mlx4_en_sqp_event;
873 	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
874 				priv->rx_ring[0].cqn, &context);
875 
876 	ptr = ((void *) &context) + 0x3c;
877 	rss_context = ptr;
878 	rss_context->base_qpn = cpu_to_be32(ilog2(priv->rx_ring_num) << 24 |
879 					    (rss_map->base_qpn));
880 	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
881 	rss_context->flags = rss_mask;
882 	rss_context->hash_fn = 1;
883 	for (i = 0; i < 10; i++)
884 		rss_context->rss_key[i] = rsskey[i];
885 
886 	if (priv->mdev->profile.udp_rss)
887 		rss_context->base_qpn_udp = rss_context->default_qpn;
888 	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
889 			       &rss_map->indir_qp, &rss_map->indir_state);
890 	if (err)
891 		goto indir_err;
892 
893 	return 0;
894 
895 indir_err:
896 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
897 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
898 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
899 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
900 rss_err:
901 	for (i = 0; i < good_qps; i++) {
902 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
903 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
904 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
905 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
906 	}
907 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
908 	return err;
909 }
910 
911 void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
912 {
913 	struct mlx4_en_dev *mdev = priv->mdev;
914 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
915 	int i;
916 
917 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
918 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
919 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
920 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
921 
922 	for (i = 0; i < priv->rx_ring_num; i++) {
923 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
924 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
925 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
926 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
927 	}
928 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
929 }
930 
931 
932 
933 
934 
935