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/mlx4/cq.h>
36 #include <linux/slab.h>
37 #include <linux/mlx4/qp.h>
38 #include <linux/skbuff.h>
39 #include <linux/rculist.h>
40 #include <linux/if_ether.h>
41 #include <linux/if_vlan.h>
42 #include <linux/vmalloc.h>
43 
44 #include "mlx4_en.h"
45 
46 static int mlx4_alloc_pages(struct mlx4_en_priv *priv,
47 			    struct mlx4_en_rx_alloc *page_alloc,
48 			    const struct mlx4_en_frag_info *frag_info,
49 			    gfp_t _gfp)
50 {
51 	int order;
52 	struct page *page;
53 	dma_addr_t dma;
54 
55 	for (order = MLX4_EN_ALLOC_PREFER_ORDER; ;) {
56 		gfp_t gfp = _gfp;
57 
58 		if (order)
59 			gfp |= __GFP_COMP | __GFP_NOWARN;
60 		page = alloc_pages(gfp, order);
61 		if (likely(page))
62 			break;
63 		if (--order < 0 ||
64 		    ((PAGE_SIZE << order) < frag_info->frag_size))
65 			return -ENOMEM;
66 	}
67 	dma = dma_map_page(priv->ddev, page, 0, PAGE_SIZE << order,
68 			   PCI_DMA_FROMDEVICE);
69 	if (dma_mapping_error(priv->ddev, dma)) {
70 		put_page(page);
71 		return -ENOMEM;
72 	}
73 	page_alloc->size = PAGE_SIZE << order;
74 	page_alloc->page = page;
75 	page_alloc->dma = dma;
76 	page_alloc->offset = frag_info->frag_align;
77 	/* Not doing get_page() for each frag is a big win
78 	 * on asymetric workloads.
79 	 */
80 	atomic_set(&page->_count, page_alloc->size / frag_info->frag_stride);
81 	return 0;
82 }
83 
84 static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv,
85 			       struct mlx4_en_rx_desc *rx_desc,
86 			       struct mlx4_en_rx_alloc *frags,
87 			       struct mlx4_en_rx_alloc *ring_alloc,
88 			       gfp_t gfp)
89 {
90 	struct mlx4_en_rx_alloc page_alloc[MLX4_EN_MAX_RX_FRAGS];
91 	const struct mlx4_en_frag_info *frag_info;
92 	struct page *page;
93 	dma_addr_t dma;
94 	int i;
95 
96 	for (i = 0; i < priv->num_frags; i++) {
97 		frag_info = &priv->frag_info[i];
98 		page_alloc[i] = ring_alloc[i];
99 		page_alloc[i].offset += frag_info->frag_stride;
100 		if (page_alloc[i].offset + frag_info->frag_stride <= ring_alloc[i].size)
101 			continue;
102 		if (mlx4_alloc_pages(priv, &page_alloc[i], frag_info, gfp))
103 			goto out;
104 	}
105 
106 	for (i = 0; i < priv->num_frags; i++) {
107 		frags[i] = ring_alloc[i];
108 		dma = ring_alloc[i].dma + ring_alloc[i].offset;
109 		ring_alloc[i] = page_alloc[i];
110 		rx_desc->data[i].addr = cpu_to_be64(dma);
111 	}
112 
113 	return 0;
114 
115 out:
116 	while (i--) {
117 		frag_info = &priv->frag_info[i];
118 		if (page_alloc[i].page != ring_alloc[i].page) {
119 			dma_unmap_page(priv->ddev, page_alloc[i].dma,
120 				page_alloc[i].size, PCI_DMA_FROMDEVICE);
121 			page = page_alloc[i].page;
122 			atomic_set(&page->_count, 1);
123 			put_page(page);
124 		}
125 	}
126 	return -ENOMEM;
127 }
128 
129 static void mlx4_en_free_frag(struct mlx4_en_priv *priv,
130 			      struct mlx4_en_rx_alloc *frags,
131 			      int i)
132 {
133 	const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
134 
135 	if (frags[i].offset + frag_info->frag_stride > frags[i].size)
136 		dma_unmap_page(priv->ddev, frags[i].dma, frags[i].size,
137 					 PCI_DMA_FROMDEVICE);
138 
139 	if (frags[i].page)
140 		put_page(frags[i].page);
141 }
142 
143 static int mlx4_en_init_allocator(struct mlx4_en_priv *priv,
144 				  struct mlx4_en_rx_ring *ring)
145 {
146 	int i;
147 	struct mlx4_en_rx_alloc *page_alloc;
148 
149 	for (i = 0; i < priv->num_frags; i++) {
150 		const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
151 
152 		if (mlx4_alloc_pages(priv, &ring->page_alloc[i],
153 				     frag_info, GFP_KERNEL))
154 			goto out;
155 	}
156 	return 0;
157 
158 out:
159 	while (i--) {
160 		struct page *page;
161 
162 		page_alloc = &ring->page_alloc[i];
163 		dma_unmap_page(priv->ddev, page_alloc->dma,
164 			       page_alloc->size, PCI_DMA_FROMDEVICE);
165 		page = page_alloc->page;
166 		atomic_set(&page->_count, 1);
167 		put_page(page);
168 		page_alloc->page = NULL;
169 	}
170 	return -ENOMEM;
171 }
172 
173 static void mlx4_en_destroy_allocator(struct mlx4_en_priv *priv,
174 				      struct mlx4_en_rx_ring *ring)
175 {
176 	struct mlx4_en_rx_alloc *page_alloc;
177 	int i;
178 
179 	for (i = 0; i < priv->num_frags; i++) {
180 		const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
181 
182 		page_alloc = &ring->page_alloc[i];
183 		en_dbg(DRV, priv, "Freeing allocator:%d count:%d\n",
184 		       i, page_count(page_alloc->page));
185 
186 		dma_unmap_page(priv->ddev, page_alloc->dma,
187 				page_alloc->size, PCI_DMA_FROMDEVICE);
188 		while (page_alloc->offset + frag_info->frag_stride < page_alloc->size) {
189 			put_page(page_alloc->page);
190 			page_alloc->offset += frag_info->frag_stride;
191 		}
192 		page_alloc->page = NULL;
193 	}
194 }
195 
196 static void mlx4_en_init_rx_desc(struct mlx4_en_priv *priv,
197 				 struct mlx4_en_rx_ring *ring, int index)
198 {
199 	struct mlx4_en_rx_desc *rx_desc = ring->buf + ring->stride * index;
200 	int possible_frags;
201 	int i;
202 
203 	/* Set size and memtype fields */
204 	for (i = 0; i < priv->num_frags; i++) {
205 		rx_desc->data[i].byte_count =
206 			cpu_to_be32(priv->frag_info[i].frag_size);
207 		rx_desc->data[i].lkey = cpu_to_be32(priv->mdev->mr.key);
208 	}
209 
210 	/* If the number of used fragments does not fill up the ring stride,
211 	 * remaining (unused) fragments must be padded with null address/size
212 	 * and a special memory key */
213 	possible_frags = (ring->stride - sizeof(struct mlx4_en_rx_desc)) / DS_SIZE;
214 	for (i = priv->num_frags; i < possible_frags; i++) {
215 		rx_desc->data[i].byte_count = 0;
216 		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
217 		rx_desc->data[i].addr = 0;
218 	}
219 }
220 
221 static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
222 				   struct mlx4_en_rx_ring *ring, int index,
223 				   gfp_t gfp)
224 {
225 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index * ring->stride);
226 	struct mlx4_en_rx_alloc *frags = ring->rx_info +
227 					(index << priv->log_rx_info);
228 
229 	return mlx4_en_alloc_frags(priv, rx_desc, frags, ring->page_alloc, gfp);
230 }
231 
232 static inline void mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
233 {
234 	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
235 }
236 
237 static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv,
238 				 struct mlx4_en_rx_ring *ring,
239 				 int index)
240 {
241 	struct mlx4_en_rx_alloc *frags;
242 	int nr;
243 
244 	frags = ring->rx_info + (index << priv->log_rx_info);
245 	for (nr = 0; nr < priv->num_frags; nr++) {
246 		en_dbg(DRV, priv, "Freeing fragment:%d\n", nr);
247 		mlx4_en_free_frag(priv, frags, nr);
248 	}
249 }
250 
251 static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
252 {
253 	struct mlx4_en_rx_ring *ring;
254 	int ring_ind;
255 	int buf_ind;
256 	int new_size;
257 
258 	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
259 		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
260 			ring = &priv->rx_ring[ring_ind];
261 
262 			if (mlx4_en_prepare_rx_desc(priv, ring,
263 						    ring->actual_size,
264 						    GFP_KERNEL)) {
265 				if (ring->actual_size < MLX4_EN_MIN_RX_SIZE) {
266 					en_err(priv, "Failed to allocate "
267 						     "enough rx buffers\n");
268 					return -ENOMEM;
269 				} else {
270 					new_size = rounddown_pow_of_two(ring->actual_size);
271 					en_warn(priv, "Only %d buffers allocated "
272 						      "reducing ring size to %d",
273 						ring->actual_size, new_size);
274 					goto reduce_rings;
275 				}
276 			}
277 			ring->actual_size++;
278 			ring->prod++;
279 		}
280 	}
281 	return 0;
282 
283 reduce_rings:
284 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
285 		ring = &priv->rx_ring[ring_ind];
286 		while (ring->actual_size > new_size) {
287 			ring->actual_size--;
288 			ring->prod--;
289 			mlx4_en_free_rx_desc(priv, ring, ring->actual_size);
290 		}
291 	}
292 
293 	return 0;
294 }
295 
296 static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
297 				struct mlx4_en_rx_ring *ring)
298 {
299 	int index;
300 
301 	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
302 	       ring->cons, ring->prod);
303 
304 	/* Unmap and free Rx buffers */
305 	BUG_ON((u32) (ring->prod - ring->cons) > ring->actual_size);
306 	while (ring->cons != ring->prod) {
307 		index = ring->cons & ring->size_mask;
308 		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
309 		mlx4_en_free_rx_desc(priv, ring, index);
310 		++ring->cons;
311 	}
312 }
313 
314 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
315 			   struct mlx4_en_rx_ring *ring, u32 size, u16 stride)
316 {
317 	struct mlx4_en_dev *mdev = priv->mdev;
318 	int err = -ENOMEM;
319 	int tmp;
320 
321 	ring->prod = 0;
322 	ring->cons = 0;
323 	ring->size = size;
324 	ring->size_mask = size - 1;
325 	ring->stride = stride;
326 	ring->log_stride = ffs(ring->stride) - 1;
327 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
328 
329 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
330 					sizeof(struct mlx4_en_rx_alloc));
331 	ring->rx_info = vmalloc(tmp);
332 	if (!ring->rx_info)
333 		return -ENOMEM;
334 
335 	en_dbg(DRV, priv, "Allocated rx_info ring at addr:%p size:%d\n",
336 		 ring->rx_info, tmp);
337 
338 	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres,
339 				 ring->buf_size, 2 * PAGE_SIZE);
340 	if (err)
341 		goto err_ring;
342 
343 	err = mlx4_en_map_buffer(&ring->wqres.buf);
344 	if (err) {
345 		en_err(priv, "Failed to map RX buffer\n");
346 		goto err_hwq;
347 	}
348 	ring->buf = ring->wqres.buf.direct.buf;
349 
350 	ring->hwtstamp_rx_filter = priv->hwtstamp_config.rx_filter;
351 
352 	return 0;
353 
354 err_hwq:
355 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
356 err_ring:
357 	vfree(ring->rx_info);
358 	ring->rx_info = NULL;
359 	return err;
360 }
361 
362 int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
363 {
364 	struct mlx4_en_rx_ring *ring;
365 	int i;
366 	int ring_ind;
367 	int err;
368 	int stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
369 					DS_SIZE * priv->num_frags);
370 
371 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
372 		ring = &priv->rx_ring[ring_ind];
373 
374 		ring->prod = 0;
375 		ring->cons = 0;
376 		ring->actual_size = 0;
377 		ring->cqn = priv->rx_cq[ring_ind].mcq.cqn;
378 
379 		ring->stride = stride;
380 		if (ring->stride <= TXBB_SIZE)
381 			ring->buf += TXBB_SIZE;
382 
383 		ring->log_stride = ffs(ring->stride) - 1;
384 		ring->buf_size = ring->size * ring->stride;
385 
386 		memset(ring->buf, 0, ring->buf_size);
387 		mlx4_en_update_rx_prod_db(ring);
388 
389 		/* Initialize all descriptors */
390 		for (i = 0; i < ring->size; i++)
391 			mlx4_en_init_rx_desc(priv, ring, i);
392 
393 		/* Initialize page allocators */
394 		err = mlx4_en_init_allocator(priv, ring);
395 		if (err) {
396 			en_err(priv, "Failed initializing ring allocator\n");
397 			if (ring->stride <= TXBB_SIZE)
398 				ring->buf -= TXBB_SIZE;
399 			ring_ind--;
400 			goto err_allocator;
401 		}
402 	}
403 	err = mlx4_en_fill_rx_buffers(priv);
404 	if (err)
405 		goto err_buffers;
406 
407 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
408 		ring = &priv->rx_ring[ring_ind];
409 
410 		ring->size_mask = ring->actual_size - 1;
411 		mlx4_en_update_rx_prod_db(ring);
412 	}
413 
414 	return 0;
415 
416 err_buffers:
417 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
418 		mlx4_en_free_rx_buf(priv, &priv->rx_ring[ring_ind]);
419 
420 	ring_ind = priv->rx_ring_num - 1;
421 err_allocator:
422 	while (ring_ind >= 0) {
423 		if (priv->rx_ring[ring_ind].stride <= TXBB_SIZE)
424 			priv->rx_ring[ring_ind].buf -= TXBB_SIZE;
425 		mlx4_en_destroy_allocator(priv, &priv->rx_ring[ring_ind]);
426 		ring_ind--;
427 	}
428 	return err;
429 }
430 
431 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
432 			     struct mlx4_en_rx_ring *ring, u32 size, u16 stride)
433 {
434 	struct mlx4_en_dev *mdev = priv->mdev;
435 
436 	mlx4_en_unmap_buffer(&ring->wqres.buf);
437 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
438 	vfree(ring->rx_info);
439 	ring->rx_info = NULL;
440 #ifdef CONFIG_RFS_ACCEL
441 	mlx4_en_cleanup_filters(priv, ring);
442 #endif
443 }
444 
445 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
446 				struct mlx4_en_rx_ring *ring)
447 {
448 	mlx4_en_free_rx_buf(priv, ring);
449 	if (ring->stride <= TXBB_SIZE)
450 		ring->buf -= TXBB_SIZE;
451 	mlx4_en_destroy_allocator(priv, ring);
452 }
453 
454 
455 static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
456 				    struct mlx4_en_rx_desc *rx_desc,
457 				    struct mlx4_en_rx_alloc *frags,
458 				    struct sk_buff *skb,
459 				    int length)
460 {
461 	struct skb_frag_struct *skb_frags_rx = skb_shinfo(skb)->frags;
462 	struct mlx4_en_frag_info *frag_info;
463 	int nr;
464 	dma_addr_t dma;
465 
466 	/* Collect used fragments while replacing them in the HW descriptors */
467 	for (nr = 0; nr < priv->num_frags; nr++) {
468 		frag_info = &priv->frag_info[nr];
469 		if (length <= frag_info->frag_prefix_size)
470 			break;
471 		if (!frags[nr].page)
472 			goto fail;
473 
474 		dma = be64_to_cpu(rx_desc->data[nr].addr);
475 		dma_sync_single_for_cpu(priv->ddev, dma, frag_info->frag_size,
476 					DMA_FROM_DEVICE);
477 
478 		/* Save page reference in skb */
479 		__skb_frag_set_page(&skb_frags_rx[nr], frags[nr].page);
480 		skb_frag_size_set(&skb_frags_rx[nr], frag_info->frag_size);
481 		skb_frags_rx[nr].page_offset = frags[nr].offset;
482 		skb->truesize += frag_info->frag_stride;
483 		frags[nr].page = NULL;
484 	}
485 	/* Adjust size of last fragment to match actual length */
486 	if (nr > 0)
487 		skb_frag_size_set(&skb_frags_rx[nr - 1],
488 			length - priv->frag_info[nr - 1].frag_prefix_size);
489 	return nr;
490 
491 fail:
492 	while (nr > 0) {
493 		nr--;
494 		__skb_frag_unref(&skb_frags_rx[nr]);
495 	}
496 	return 0;
497 }
498 
499 
500 static struct sk_buff *mlx4_en_rx_skb(struct mlx4_en_priv *priv,
501 				      struct mlx4_en_rx_desc *rx_desc,
502 				      struct mlx4_en_rx_alloc *frags,
503 				      unsigned int length)
504 {
505 	struct sk_buff *skb;
506 	void *va;
507 	int used_frags;
508 	dma_addr_t dma;
509 
510 	skb = netdev_alloc_skb(priv->dev, SMALL_PACKET_SIZE + NET_IP_ALIGN);
511 	if (!skb) {
512 		en_dbg(RX_ERR, priv, "Failed allocating skb\n");
513 		return NULL;
514 	}
515 	skb_reserve(skb, NET_IP_ALIGN);
516 	skb->len = length;
517 
518 	/* Get pointer to first fragment so we could copy the headers into the
519 	 * (linear part of the) skb */
520 	va = page_address(frags[0].page) + frags[0].offset;
521 
522 	if (length <= SMALL_PACKET_SIZE) {
523 		/* We are copying all relevant data to the skb - temporarily
524 		 * sync buffers for the copy */
525 		dma = be64_to_cpu(rx_desc->data[0].addr);
526 		dma_sync_single_for_cpu(priv->ddev, dma, length,
527 					DMA_FROM_DEVICE);
528 		skb_copy_to_linear_data(skb, va, length);
529 		skb->tail += length;
530 	} else {
531 		/* Move relevant fragments to skb */
532 		used_frags = mlx4_en_complete_rx_desc(priv, rx_desc, frags,
533 							skb, length);
534 		if (unlikely(!used_frags)) {
535 			kfree_skb(skb);
536 			return NULL;
537 		}
538 		skb_shinfo(skb)->nr_frags = used_frags;
539 
540 		/* Copy headers into the skb linear buffer */
541 		memcpy(skb->data, va, HEADER_COPY_SIZE);
542 		skb->tail += HEADER_COPY_SIZE;
543 
544 		/* Skip headers in first fragment */
545 		skb_shinfo(skb)->frags[0].page_offset += HEADER_COPY_SIZE;
546 
547 		/* Adjust size of first fragment */
548 		skb_frag_size_sub(&skb_shinfo(skb)->frags[0], HEADER_COPY_SIZE);
549 		skb->data_len = length - HEADER_COPY_SIZE;
550 	}
551 	return skb;
552 }
553 
554 static void validate_loopback(struct mlx4_en_priv *priv, struct sk_buff *skb)
555 {
556 	int i;
557 	int offset = ETH_HLEN;
558 
559 	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++, offset++) {
560 		if (*(skb->data + offset) != (unsigned char) (i & 0xff))
561 			goto out_loopback;
562 	}
563 	/* Loopback found */
564 	priv->loopback_ok = 1;
565 
566 out_loopback:
567 	dev_kfree_skb_any(skb);
568 }
569 
570 static void mlx4_en_refill_rx_buffers(struct mlx4_en_priv *priv,
571 				     struct mlx4_en_rx_ring *ring)
572 {
573 	int index = ring->prod & ring->size_mask;
574 
575 	while ((u32) (ring->prod - ring->cons) < ring->actual_size) {
576 		if (mlx4_en_prepare_rx_desc(priv, ring, index, GFP_ATOMIC))
577 			break;
578 		ring->prod++;
579 		index = ring->prod & ring->size_mask;
580 	}
581 }
582 
583 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
584 {
585 	struct mlx4_en_priv *priv = netdev_priv(dev);
586 	struct mlx4_en_dev *mdev = priv->mdev;
587 	struct mlx4_cqe *cqe;
588 	struct mlx4_en_rx_ring *ring = &priv->rx_ring[cq->ring];
589 	struct mlx4_en_rx_alloc *frags;
590 	struct mlx4_en_rx_desc *rx_desc;
591 	struct sk_buff *skb;
592 	int index;
593 	int nr;
594 	unsigned int length;
595 	int polled = 0;
596 	int ip_summed;
597 	int factor = priv->cqe_factor;
598 	u64 timestamp;
599 
600 	if (!priv->port_up)
601 		return 0;
602 
603 	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
604 	 * descriptor offset can be deduced from the CQE index instead of
605 	 * reading 'cqe->index' */
606 	index = cq->mcq.cons_index & ring->size_mask;
607 	cqe = &cq->buf[(index << factor) + factor];
608 
609 	/* Process all completed CQEs */
610 	while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
611 		    cq->mcq.cons_index & cq->size)) {
612 
613 		frags = ring->rx_info + (index << priv->log_rx_info);
614 		rx_desc = ring->buf + (index << ring->log_stride);
615 
616 		/*
617 		 * make sure we read the CQE after we read the ownership bit
618 		 */
619 		rmb();
620 
621 		/* Drop packet on bad receive or bad checksum */
622 		if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
623 						MLX4_CQE_OPCODE_ERROR)) {
624 			en_err(priv, "CQE completed in error - vendor "
625 				  "syndrom:%d syndrom:%d\n",
626 				  ((struct mlx4_err_cqe *) cqe)->vendor_err_syndrome,
627 				  ((struct mlx4_err_cqe *) cqe)->syndrome);
628 			goto next;
629 		}
630 		if (unlikely(cqe->badfcs_enc & MLX4_CQE_BAD_FCS)) {
631 			en_dbg(RX_ERR, priv, "Accepted frame with bad FCS\n");
632 			goto next;
633 		}
634 
635 		/* Check if we need to drop the packet if SRIOV is not enabled
636 		 * and not performing the selftest or flb disabled
637 		 */
638 		if (priv->flags & MLX4_EN_FLAG_RX_FILTER_NEEDED) {
639 			struct ethhdr *ethh;
640 			dma_addr_t dma;
641 			/* Get pointer to first fragment since we haven't
642 			 * skb yet and cast it to ethhdr struct
643 			 */
644 			dma = be64_to_cpu(rx_desc->data[0].addr);
645 			dma_sync_single_for_cpu(priv->ddev, dma, sizeof(*ethh),
646 						DMA_FROM_DEVICE);
647 			ethh = (struct ethhdr *)(page_address(frags[0].page) +
648 						 frags[0].offset);
649 
650 			if (is_multicast_ether_addr(ethh->h_dest)) {
651 				struct mlx4_mac_entry *entry;
652 				struct hlist_head *bucket;
653 				unsigned int mac_hash;
654 
655 				/* Drop the packet, since HW loopback-ed it */
656 				mac_hash = ethh->h_source[MLX4_EN_MAC_HASH_IDX];
657 				bucket = &priv->mac_hash[mac_hash];
658 				rcu_read_lock();
659 				hlist_for_each_entry_rcu(entry, bucket, hlist) {
660 					if (ether_addr_equal_64bits(entry->mac,
661 								    ethh->h_source)) {
662 						rcu_read_unlock();
663 						goto next;
664 					}
665 				}
666 				rcu_read_unlock();
667 			}
668 		}
669 
670 		/*
671 		 * Packet is OK - process it.
672 		 */
673 		length = be32_to_cpu(cqe->byte_cnt);
674 		length -= ring->fcs_del;
675 		ring->bytes += length;
676 		ring->packets++;
677 
678 		if (likely(dev->features & NETIF_F_RXCSUM)) {
679 			if ((cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
680 			    (cqe->checksum == cpu_to_be16(0xffff))) {
681 				ring->csum_ok++;
682 				/* This packet is eligible for GRO if it is:
683 				 * - DIX Ethernet (type interpretation)
684 				 * - TCP/IP (v4)
685 				 * - without IP options
686 				 * - not an IP fragment
687 				 * - no LLS polling in progress
688 				 */
689 				if (!mlx4_en_cq_ll_polling(cq) &&
690 				    (dev->features & NETIF_F_GRO)) {
691 					struct sk_buff *gro_skb = napi_get_frags(&cq->napi);
692 					if (!gro_skb)
693 						goto next;
694 
695 					nr = mlx4_en_complete_rx_desc(priv,
696 						rx_desc, frags, gro_skb,
697 						length);
698 					if (!nr)
699 						goto next;
700 
701 					skb_shinfo(gro_skb)->nr_frags = nr;
702 					gro_skb->len = length;
703 					gro_skb->data_len = length;
704 					gro_skb->ip_summed = CHECKSUM_UNNECESSARY;
705 
706 					if ((cqe->vlan_my_qpn &
707 					    cpu_to_be32(MLX4_CQE_VLAN_PRESENT_MASK)) &&
708 					    (dev->features & NETIF_F_HW_VLAN_CTAG_RX)) {
709 						u16 vid = be16_to_cpu(cqe->sl_vid);
710 
711 						__vlan_hwaccel_put_tag(gro_skb, htons(ETH_P_8021Q), vid);
712 					}
713 
714 					if (dev->features & NETIF_F_RXHASH)
715 						gro_skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
716 
717 					skb_record_rx_queue(gro_skb, cq->ring);
718 
719 					if (ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL) {
720 						timestamp = mlx4_en_get_cqe_ts(cqe);
721 						mlx4_en_fill_hwtstamps(mdev,
722 								       skb_hwtstamps(gro_skb),
723 								       timestamp);
724 					}
725 
726 					napi_gro_frags(&cq->napi);
727 					goto next;
728 				}
729 
730 				/* GRO not possible, complete processing here */
731 				ip_summed = CHECKSUM_UNNECESSARY;
732 			} else {
733 				ip_summed = CHECKSUM_NONE;
734 				ring->csum_none++;
735 			}
736 		} else {
737 			ip_summed = CHECKSUM_NONE;
738 			ring->csum_none++;
739 		}
740 
741 		skb = mlx4_en_rx_skb(priv, rx_desc, frags, length);
742 		if (!skb) {
743 			priv->stats.rx_dropped++;
744 			goto next;
745 		}
746 
747                 if (unlikely(priv->validate_loopback)) {
748 			validate_loopback(priv, skb);
749 			goto next;
750 		}
751 
752 		skb->ip_summed = ip_summed;
753 		skb->protocol = eth_type_trans(skb, dev);
754 		skb_record_rx_queue(skb, cq->ring);
755 
756 		if (dev->features & NETIF_F_RXHASH)
757 			skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
758 
759 		if ((be32_to_cpu(cqe->vlan_my_qpn) &
760 		    MLX4_CQE_VLAN_PRESENT_MASK) &&
761 		    (dev->features & NETIF_F_HW_VLAN_CTAG_RX))
762 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), be16_to_cpu(cqe->sl_vid));
763 
764 		if (ring->hwtstamp_rx_filter == HWTSTAMP_FILTER_ALL) {
765 			timestamp = mlx4_en_get_cqe_ts(cqe);
766 			mlx4_en_fill_hwtstamps(mdev, skb_hwtstamps(skb),
767 					       timestamp);
768 		}
769 
770 		skb_mark_napi_id(skb, &cq->napi);
771 
772 		/* Push it up the stack */
773 		netif_receive_skb(skb);
774 
775 next:
776 		for (nr = 0; nr < priv->num_frags; nr++)
777 			mlx4_en_free_frag(priv, frags, nr);
778 
779 		++cq->mcq.cons_index;
780 		index = (cq->mcq.cons_index) & ring->size_mask;
781 		cqe = &cq->buf[(index << factor) + factor];
782 		if (++polled == budget)
783 			goto out;
784 	}
785 
786 out:
787 	AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
788 	mlx4_cq_set_ci(&cq->mcq);
789 	wmb(); /* ensure HW sees CQ consumer before we post new buffers */
790 	ring->cons = cq->mcq.cons_index;
791 	mlx4_en_refill_rx_buffers(priv, ring);
792 	mlx4_en_update_rx_prod_db(ring);
793 	return polled;
794 }
795 
796 
797 void mlx4_en_rx_irq(struct mlx4_cq *mcq)
798 {
799 	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
800 	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
801 
802 	if (priv->port_up)
803 		napi_schedule(&cq->napi);
804 	else
805 		mlx4_en_arm_cq(priv, cq);
806 }
807 
808 /* Rx CQ polling - called by NAPI */
809 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget)
810 {
811 	struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
812 	struct net_device *dev = cq->dev;
813 	struct mlx4_en_priv *priv = netdev_priv(dev);
814 	int done;
815 
816 	if (!mlx4_en_cq_lock_napi(cq))
817 		return budget;
818 
819 	done = mlx4_en_process_rx_cq(dev, cq, budget);
820 
821 	mlx4_en_cq_unlock_napi(cq);
822 
823 	/* If we used up all the quota - we're probably not done yet... */
824 	if (done == budget)
825 		INC_PERF_COUNTER(priv->pstats.napi_quota);
826 	else {
827 		/* Done for now */
828 		napi_complete(napi);
829 		mlx4_en_arm_cq(priv, cq);
830 	}
831 	return done;
832 }
833 
834 static const int frag_sizes[] = {
835 	FRAG_SZ0,
836 	FRAG_SZ1,
837 	FRAG_SZ2,
838 	FRAG_SZ3
839 };
840 
841 void mlx4_en_calc_rx_buf(struct net_device *dev)
842 {
843 	struct mlx4_en_priv *priv = netdev_priv(dev);
844 	int eff_mtu = dev->mtu + ETH_HLEN + VLAN_HLEN + ETH_LLC_SNAP_SIZE;
845 	int buf_size = 0;
846 	int i = 0;
847 
848 	while (buf_size < eff_mtu) {
849 		priv->frag_info[i].frag_size =
850 			(eff_mtu > buf_size + frag_sizes[i]) ?
851 				frag_sizes[i] : eff_mtu - buf_size;
852 		priv->frag_info[i].frag_prefix_size = buf_size;
853 		if (!i)	{
854 			priv->frag_info[i].frag_align = NET_IP_ALIGN;
855 			priv->frag_info[i].frag_stride =
856 				ALIGN(frag_sizes[i] + NET_IP_ALIGN, SMP_CACHE_BYTES);
857 		} else {
858 			priv->frag_info[i].frag_align = 0;
859 			priv->frag_info[i].frag_stride =
860 				ALIGN(frag_sizes[i], SMP_CACHE_BYTES);
861 		}
862 		buf_size += priv->frag_info[i].frag_size;
863 		i++;
864 	}
865 
866 	priv->num_frags = i;
867 	priv->rx_skb_size = eff_mtu;
868 	priv->log_rx_info = ROUNDUP_LOG2(i * sizeof(struct mlx4_en_rx_alloc));
869 
870 	en_dbg(DRV, priv, "Rx buffer scatter-list (effective-mtu:%d "
871 		  "num_frags:%d):\n", eff_mtu, priv->num_frags);
872 	for (i = 0; i < priv->num_frags; i++) {
873 		en_err(priv,
874 		       "  frag:%d - size:%d prefix:%d align:%d stride:%d\n",
875 		       i,
876 		       priv->frag_info[i].frag_size,
877 		       priv->frag_info[i].frag_prefix_size,
878 		       priv->frag_info[i].frag_align,
879 		       priv->frag_info[i].frag_stride);
880 	}
881 }
882 
883 /* RSS related functions */
884 
885 static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
886 				 struct mlx4_en_rx_ring *ring,
887 				 enum mlx4_qp_state *state,
888 				 struct mlx4_qp *qp)
889 {
890 	struct mlx4_en_dev *mdev = priv->mdev;
891 	struct mlx4_qp_context *context;
892 	int err = 0;
893 
894 	context = kmalloc(sizeof(*context), GFP_KERNEL);
895 	if (!context)
896 		return -ENOMEM;
897 
898 	err = mlx4_qp_alloc(mdev->dev, qpn, qp);
899 	if (err) {
900 		en_err(priv, "Failed to allocate qp #%x\n", qpn);
901 		goto out;
902 	}
903 	qp->event = mlx4_en_sqp_event;
904 
905 	memset(context, 0, sizeof *context);
906 	mlx4_en_fill_qp_context(priv, ring->actual_size, ring->stride, 0, 0,
907 				qpn, ring->cqn, -1, context);
908 	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);
909 
910 	/* Cancel FCS removal if FW allows */
911 	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
912 		context->param3 |= cpu_to_be32(1 << 29);
913 		ring->fcs_del = ETH_FCS_LEN;
914 	} else
915 		ring->fcs_del = 0;
916 
917 	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
918 	if (err) {
919 		mlx4_qp_remove(mdev->dev, qp);
920 		mlx4_qp_free(mdev->dev, qp);
921 	}
922 	mlx4_en_update_rx_prod_db(ring);
923 out:
924 	kfree(context);
925 	return err;
926 }
927 
928 int mlx4_en_create_drop_qp(struct mlx4_en_priv *priv)
929 {
930 	int err;
931 	u32 qpn;
932 
933 	err = mlx4_qp_reserve_range(priv->mdev->dev, 1, 1, &qpn);
934 	if (err) {
935 		en_err(priv, "Failed reserving drop qpn\n");
936 		return err;
937 	}
938 	err = mlx4_qp_alloc(priv->mdev->dev, qpn, &priv->drop_qp);
939 	if (err) {
940 		en_err(priv, "Failed allocating drop qp\n");
941 		mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
942 		return err;
943 	}
944 
945 	return 0;
946 }
947 
948 void mlx4_en_destroy_drop_qp(struct mlx4_en_priv *priv)
949 {
950 	u32 qpn;
951 
952 	qpn = priv->drop_qp.qpn;
953 	mlx4_qp_remove(priv->mdev->dev, &priv->drop_qp);
954 	mlx4_qp_free(priv->mdev->dev, &priv->drop_qp);
955 	mlx4_qp_release_range(priv->mdev->dev, qpn, 1);
956 }
957 
958 /* Allocate rx qp's and configure them according to rss map */
959 int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
960 {
961 	struct mlx4_en_dev *mdev = priv->mdev;
962 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
963 	struct mlx4_qp_context context;
964 	struct mlx4_rss_context *rss_context;
965 	int rss_rings;
966 	void *ptr;
967 	u8 rss_mask = (MLX4_RSS_IPV4 | MLX4_RSS_TCP_IPV4 | MLX4_RSS_IPV6 |
968 			MLX4_RSS_TCP_IPV6);
969 	int i, qpn;
970 	int err = 0;
971 	int good_qps = 0;
972 	static const u32 rsskey[10] = { 0xD181C62C, 0xF7F4DB5B, 0x1983A2FC,
973 				0x943E1ADB, 0xD9389E6B, 0xD1039C2C, 0xA74499AD,
974 				0x593D56D9, 0xF3253C06, 0x2ADC1FFC};
975 
976 	en_dbg(DRV, priv, "Configuring rss steering\n");
977 	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
978 				    priv->rx_ring_num,
979 				    &rss_map->base_qpn);
980 	if (err) {
981 		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
982 		return err;
983 	}
984 
985 	for (i = 0; i < priv->rx_ring_num; i++) {
986 		qpn = rss_map->base_qpn + i;
987 		err = mlx4_en_config_rss_qp(priv, qpn, &priv->rx_ring[i],
988 					    &rss_map->state[i],
989 					    &rss_map->qps[i]);
990 		if (err)
991 			goto rss_err;
992 
993 		++good_qps;
994 	}
995 
996 	/* Configure RSS indirection qp */
997 	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp);
998 	if (err) {
999 		en_err(priv, "Failed to allocate RSS indirection QP\n");
1000 		goto rss_err;
1001 	}
1002 	rss_map->indir_qp.event = mlx4_en_sqp_event;
1003 	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
1004 				priv->rx_ring[0].cqn, -1, &context);
1005 
1006 	if (!priv->prof->rss_rings || priv->prof->rss_rings > priv->rx_ring_num)
1007 		rss_rings = priv->rx_ring_num;
1008 	else
1009 		rss_rings = priv->prof->rss_rings;
1010 
1011 	ptr = ((void *) &context) + offsetof(struct mlx4_qp_context, pri_path)
1012 					+ MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
1013 	rss_context = ptr;
1014 	rss_context->base_qpn = cpu_to_be32(ilog2(rss_rings) << 24 |
1015 					    (rss_map->base_qpn));
1016 	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
1017 	if (priv->mdev->profile.udp_rss) {
1018 		rss_mask |=  MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6;
1019 		rss_context->base_qpn_udp = rss_context->default_qpn;
1020 	}
1021 	rss_context->flags = rss_mask;
1022 	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
1023 	for (i = 0; i < 10; i++)
1024 		rss_context->rss_key[i] = cpu_to_be32(rsskey[i]);
1025 
1026 	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
1027 			       &rss_map->indir_qp, &rss_map->indir_state);
1028 	if (err)
1029 		goto indir_err;
1030 
1031 	return 0;
1032 
1033 indir_err:
1034 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1035 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
1036 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
1037 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
1038 rss_err:
1039 	for (i = 0; i < good_qps; i++) {
1040 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1041 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1042 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1043 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1044 	}
1045 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1046 	return err;
1047 }
1048 
1049 void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
1050 {
1051 	struct mlx4_en_dev *mdev = priv->mdev;
1052 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
1053 	int i;
1054 
1055 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
1056 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
1057 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
1058 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
1059 
1060 	for (i = 0; i < priv->rx_ring_num; i++) {
1061 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
1062 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
1063 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
1064 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
1065 	}
1066 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
1067 }
1068