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 
mlx4_en_alloc_frag(struct mlx4_en_priv * priv,struct mlx4_en_rx_desc * rx_desc,struct page_frag * skb_frags,struct mlx4_en_rx_alloc * ring_alloc,int i)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_frag_info *frag_info = &priv->frag_info[i];
52 	struct mlx4_en_rx_alloc *page_alloc = &ring_alloc[i];
53 	struct page *page;
54 	dma_addr_t dma;
55 
56 	if (page_alloc->offset == frag_info->last_offset) {
57 		/* Allocate new page */
58 		page = alloc_pages(GFP_ATOMIC | __GFP_COMP, MLX4_EN_ALLOC_ORDER);
59 		if (!page)
60 			return -ENOMEM;
61 
62 		skb_frags[i].page = page_alloc->page;
63 		skb_frags[i].offset = page_alloc->offset;
64 		page_alloc->page = page;
65 		page_alloc->offset = frag_info->frag_align;
66 	} else {
67 		page = page_alloc->page;
68 		get_page(page);
69 
70 		skb_frags[i].page = page;
71 		skb_frags[i].offset = page_alloc->offset;
72 		page_alloc->offset += frag_info->frag_stride;
73 	}
74 	dma = dma_map_single(priv->ddev, page_address(skb_frags[i].page) +
75 			     skb_frags[i].offset, frag_info->frag_size,
76 			     PCI_DMA_FROMDEVICE);
77 	rx_desc->data[i].addr = cpu_to_be64(dma);
78 	return 0;
79 }
80 
mlx4_en_init_allocator(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring)81 static int mlx4_en_init_allocator(struct mlx4_en_priv *priv,
82 				  struct mlx4_en_rx_ring *ring)
83 {
84 	struct mlx4_en_rx_alloc *page_alloc;
85 	int i;
86 
87 	for (i = 0; i < priv->num_frags; i++) {
88 		page_alloc = &ring->page_alloc[i];
89 		page_alloc->page = alloc_pages(GFP_ATOMIC | __GFP_COMP,
90 					       MLX4_EN_ALLOC_ORDER);
91 		if (!page_alloc->page)
92 			goto out;
93 
94 		page_alloc->offset = priv->frag_info[i].frag_align;
95 		en_dbg(DRV, priv, "Initialized allocator:%d with page:%p\n",
96 		       i, page_alloc->page);
97 	}
98 	return 0;
99 
100 out:
101 	while (i--) {
102 		page_alloc = &ring->page_alloc[i];
103 		put_page(page_alloc->page);
104 		page_alloc->page = NULL;
105 	}
106 	return -ENOMEM;
107 }
108 
mlx4_en_destroy_allocator(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring)109 static void mlx4_en_destroy_allocator(struct mlx4_en_priv *priv,
110 				      struct mlx4_en_rx_ring *ring)
111 {
112 	struct mlx4_en_rx_alloc *page_alloc;
113 	int i;
114 
115 	for (i = 0; i < priv->num_frags; i++) {
116 		page_alloc = &ring->page_alloc[i];
117 		en_dbg(DRV, priv, "Freeing allocator:%d count:%d\n",
118 		       i, page_count(page_alloc->page));
119 
120 		put_page(page_alloc->page);
121 		page_alloc->page = NULL;
122 	}
123 }
124 
125 
mlx4_en_init_rx_desc(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring,int index)126 static void mlx4_en_init_rx_desc(struct mlx4_en_priv *priv,
127 				 struct mlx4_en_rx_ring *ring, int index)
128 {
129 	struct mlx4_en_rx_desc *rx_desc = ring->buf + ring->stride * index;
130 	struct skb_frag_struct *skb_frags = ring->rx_info +
131 					    (index << priv->log_rx_info);
132 	int possible_frags;
133 	int i;
134 
135 	/* Set size and memtype fields */
136 	for (i = 0; i < priv->num_frags; i++) {
137 		skb_frag_size_set(&skb_frags[i], priv->frag_info[i].frag_size);
138 		rx_desc->data[i].byte_count =
139 			cpu_to_be32(priv->frag_info[i].frag_size);
140 		rx_desc->data[i].lkey = cpu_to_be32(priv->mdev->mr.key);
141 	}
142 
143 	/* If the number of used fragments does not fill up the ring stride,
144 	 * remaining (unused) fragments must be padded with null address/size
145 	 * and a special memory key */
146 	possible_frags = (ring->stride - sizeof(struct mlx4_en_rx_desc)) / DS_SIZE;
147 	for (i = priv->num_frags; i < possible_frags; i++) {
148 		rx_desc->data[i].byte_count = 0;
149 		rx_desc->data[i].lkey = cpu_to_be32(MLX4_EN_MEMTYPE_PAD);
150 		rx_desc->data[i].addr = 0;
151 	}
152 }
153 
154 
mlx4_en_prepare_rx_desc(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring,int index)155 static int mlx4_en_prepare_rx_desc(struct mlx4_en_priv *priv,
156 				   struct mlx4_en_rx_ring *ring, int index)
157 {
158 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index * ring->stride);
159 	struct page_frag *skb_frags = ring->rx_info +
160 				      (index << priv->log_rx_info);
161 	int i;
162 
163 	for (i = 0; i < priv->num_frags; i++)
164 		if (mlx4_en_alloc_frag(priv, rx_desc, skb_frags, ring->page_alloc, i))
165 			goto err;
166 
167 	return 0;
168 
169 err:
170 	while (i--) {
171 		dma_addr_t dma = be64_to_cpu(rx_desc->data[i].addr);
172 		pci_unmap_single(priv->mdev->pdev, dma, skb_frags[i].size,
173 				 PCI_DMA_FROMDEVICE);
174 		put_page(skb_frags[i].page);
175 	}
176 	return -ENOMEM;
177 }
178 
mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring * ring)179 static inline void mlx4_en_update_rx_prod_db(struct mlx4_en_rx_ring *ring)
180 {
181 	*ring->wqres.db.db = cpu_to_be32(ring->prod & 0xffff);
182 }
183 
mlx4_en_free_rx_desc(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring,int index)184 static void mlx4_en_free_rx_desc(struct mlx4_en_priv *priv,
185 				 struct mlx4_en_rx_ring *ring,
186 				 int index)
187 {
188 	struct page_frag *skb_frags;
189 	struct mlx4_en_rx_desc *rx_desc = ring->buf + (index << ring->log_stride);
190 	dma_addr_t dma;
191 	int nr;
192 
193 	skb_frags = ring->rx_info + (index << priv->log_rx_info);
194 	for (nr = 0; nr < priv->num_frags; nr++) {
195 		en_dbg(DRV, priv, "Freeing fragment:%d\n", nr);
196 		dma = be64_to_cpu(rx_desc->data[nr].addr);
197 
198 		en_dbg(DRV, priv, "Unmapping buffer at dma:0x%llx\n", (u64) dma);
199 		dma_unmap_single(priv->ddev, dma, skb_frags[nr].size,
200 				 PCI_DMA_FROMDEVICE);
201 		put_page(skb_frags[nr].page);
202 	}
203 }
204 
mlx4_en_fill_rx_buffers(struct mlx4_en_priv * priv)205 static int mlx4_en_fill_rx_buffers(struct mlx4_en_priv *priv)
206 {
207 	struct mlx4_en_rx_ring *ring;
208 	int ring_ind;
209 	int buf_ind;
210 	int new_size;
211 
212 	for (buf_ind = 0; buf_ind < priv->prof->rx_ring_size; buf_ind++) {
213 		for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
214 			ring = &priv->rx_ring[ring_ind];
215 
216 			if (mlx4_en_prepare_rx_desc(priv, ring,
217 						    ring->actual_size)) {
218 				if (ring->actual_size < MLX4_EN_MIN_RX_SIZE) {
219 					en_err(priv, "Failed to allocate "
220 						     "enough rx buffers\n");
221 					return -ENOMEM;
222 				} else {
223 					new_size = rounddown_pow_of_two(ring->actual_size);
224 					en_warn(priv, "Only %d buffers allocated "
225 						      "reducing ring size to %d",
226 						ring->actual_size, new_size);
227 					goto reduce_rings;
228 				}
229 			}
230 			ring->actual_size++;
231 			ring->prod++;
232 		}
233 	}
234 	return 0;
235 
236 reduce_rings:
237 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
238 		ring = &priv->rx_ring[ring_ind];
239 		while (ring->actual_size > new_size) {
240 			ring->actual_size--;
241 			ring->prod--;
242 			mlx4_en_free_rx_desc(priv, ring, ring->actual_size);
243 		}
244 	}
245 
246 	return 0;
247 }
248 
mlx4_en_free_rx_buf(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring)249 static void mlx4_en_free_rx_buf(struct mlx4_en_priv *priv,
250 				struct mlx4_en_rx_ring *ring)
251 {
252 	int index;
253 
254 	en_dbg(DRV, priv, "Freeing Rx buf - cons:%d prod:%d\n",
255 	       ring->cons, ring->prod);
256 
257 	/* Unmap and free Rx buffers */
258 	BUG_ON((u32) (ring->prod - ring->cons) > ring->actual_size);
259 	while (ring->cons != ring->prod) {
260 		index = ring->cons & ring->size_mask;
261 		en_dbg(DRV, priv, "Processing descriptor:%d\n", index);
262 		mlx4_en_free_rx_desc(priv, ring, index);
263 		++ring->cons;
264 	}
265 }
266 
mlx4_en_create_rx_ring(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring,u32 size,u16 stride)267 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
268 			   struct mlx4_en_rx_ring *ring, u32 size, u16 stride)
269 {
270 	struct mlx4_en_dev *mdev = priv->mdev;
271 	int err;
272 	int tmp;
273 
274 
275 	ring->prod = 0;
276 	ring->cons = 0;
277 	ring->size = size;
278 	ring->size_mask = size - 1;
279 	ring->stride = stride;
280 	ring->log_stride = ffs(ring->stride) - 1;
281 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
282 
283 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
284 					sizeof(struct skb_frag_struct));
285 	ring->rx_info = vmalloc(tmp);
286 	if (!ring->rx_info)
287 		return -ENOMEM;
288 
289 	en_dbg(DRV, priv, "Allocated rx_info ring at addr:%p size:%d\n",
290 		 ring->rx_info, tmp);
291 
292 	err = mlx4_alloc_hwq_res(mdev->dev, &ring->wqres,
293 				 ring->buf_size, 2 * PAGE_SIZE);
294 	if (err)
295 		goto err_ring;
296 
297 	err = mlx4_en_map_buffer(&ring->wqres.buf);
298 	if (err) {
299 		en_err(priv, "Failed to map RX buffer\n");
300 		goto err_hwq;
301 	}
302 	ring->buf = ring->wqres.buf.direct.buf;
303 
304 	return 0;
305 
306 err_hwq:
307 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, ring->buf_size);
308 err_ring:
309 	vfree(ring->rx_info);
310 	ring->rx_info = NULL;
311 	return err;
312 }
313 
mlx4_en_activate_rx_rings(struct mlx4_en_priv * priv)314 int mlx4_en_activate_rx_rings(struct mlx4_en_priv *priv)
315 {
316 	struct mlx4_en_rx_ring *ring;
317 	int i;
318 	int ring_ind;
319 	int err;
320 	int stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
321 					DS_SIZE * priv->num_frags);
322 
323 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
324 		ring = &priv->rx_ring[ring_ind];
325 
326 		ring->prod = 0;
327 		ring->cons = 0;
328 		ring->actual_size = 0;
329 		ring->cqn = priv->rx_cq[ring_ind].mcq.cqn;
330 
331 		ring->stride = stride;
332 		if (ring->stride <= TXBB_SIZE)
333 			ring->buf += TXBB_SIZE;
334 
335 		ring->log_stride = ffs(ring->stride) - 1;
336 		ring->buf_size = ring->size * ring->stride;
337 
338 		memset(ring->buf, 0, ring->buf_size);
339 		mlx4_en_update_rx_prod_db(ring);
340 
341 		/* Initailize all descriptors */
342 		for (i = 0; i < ring->size; i++)
343 			mlx4_en_init_rx_desc(priv, ring, i);
344 
345 		/* Initialize page allocators */
346 		err = mlx4_en_init_allocator(priv, ring);
347 		if (err) {
348 			en_err(priv, "Failed initializing ring allocator\n");
349 			if (ring->stride <= TXBB_SIZE)
350 				ring->buf -= TXBB_SIZE;
351 			ring_ind--;
352 			goto err_allocator;
353 		}
354 	}
355 	err = mlx4_en_fill_rx_buffers(priv);
356 	if (err)
357 		goto err_buffers;
358 
359 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++) {
360 		ring = &priv->rx_ring[ring_ind];
361 
362 		ring->size_mask = ring->actual_size - 1;
363 		mlx4_en_update_rx_prod_db(ring);
364 	}
365 
366 	return 0;
367 
368 err_buffers:
369 	for (ring_ind = 0; ring_ind < priv->rx_ring_num; ring_ind++)
370 		mlx4_en_free_rx_buf(priv, &priv->rx_ring[ring_ind]);
371 
372 	ring_ind = priv->rx_ring_num - 1;
373 err_allocator:
374 	while (ring_ind >= 0) {
375 		if (priv->rx_ring[ring_ind].stride <= TXBB_SIZE)
376 			priv->rx_ring[ring_ind].buf -= TXBB_SIZE;
377 		mlx4_en_destroy_allocator(priv, &priv->rx_ring[ring_ind]);
378 		ring_ind--;
379 	}
380 	return err;
381 }
382 
mlx4_en_destroy_rx_ring(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring,u32 size,u16 stride)383 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
384 			     struct mlx4_en_rx_ring *ring, u32 size, u16 stride)
385 {
386 	struct mlx4_en_dev *mdev = priv->mdev;
387 
388 	mlx4_en_unmap_buffer(&ring->wqres.buf);
389 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
390 	vfree(ring->rx_info);
391 	ring->rx_info = NULL;
392 }
393 
mlx4_en_deactivate_rx_ring(struct mlx4_en_priv * priv,struct mlx4_en_rx_ring * ring)394 void mlx4_en_deactivate_rx_ring(struct mlx4_en_priv *priv,
395 				struct mlx4_en_rx_ring *ring)
396 {
397 	mlx4_en_free_rx_buf(priv, ring);
398 	if (ring->stride <= TXBB_SIZE)
399 		ring->buf -= TXBB_SIZE;
400 	mlx4_en_destroy_allocator(priv, ring);
401 }
402 
403 
404 /* Unmap a completed descriptor and free unused pages */
mlx4_en_complete_rx_desc(struct mlx4_en_priv * priv,struct mlx4_en_rx_desc * rx_desc,struct page_frag * skb_frags,struct sk_buff * skb,struct mlx4_en_rx_alloc * page_alloc,int length)405 static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
406 				    struct mlx4_en_rx_desc *rx_desc,
407 				    struct page_frag *skb_frags,
408 				    struct sk_buff *skb,
409 				    struct mlx4_en_rx_alloc *page_alloc,
410 				    int length)
411 {
412 	struct skb_frag_struct *skb_frags_rx = skb_shinfo(skb)->frags;
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 		dma_unmap_single(priv->ddev, 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 
mlx4_en_rx_skb(struct mlx4_en_priv * priv,struct mlx4_en_rx_desc * rx_desc,struct page_frag * skb_frags,struct mlx4_en_rx_alloc * page_alloc,unsigned int length)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 sk_buff *skb;
462 	void *va;
463 	int used_frags;
464 	dma_addr_t dma;
465 
466 	skb = netdev_alloc_skb(priv->dev, SMALL_PACKET_SIZE + NET_IP_ALIGN);
467 	if (!skb) {
468 		en_dbg(RX_ERR, priv, "Failed allocating skb\n");
469 		return NULL;
470 	}
471 	skb_reserve(skb, NET_IP_ALIGN);
472 	skb->len = length;
473 
474 	/* Get pointer to first fragment so we could copy the headers into the
475 	 * (linear part of the) skb */
476 	va = page_address(skb_frags[0].page) + skb_frags[0].offset;
477 
478 	if (length <= SMALL_PACKET_SIZE) {
479 		/* We are copying all relevant data to the skb - temporarily
480 		 * synch buffers for the copy */
481 		dma = be64_to_cpu(rx_desc->data[0].addr);
482 		dma_sync_single_for_cpu(priv->ddev, dma, length,
483 					DMA_FROM_DEVICE);
484 		skb_copy_to_linear_data(skb, va, length);
485 		dma_sync_single_for_device(priv->ddev, dma, length,
486 					   DMA_FROM_DEVICE);
487 		skb->tail += length;
488 	} else {
489 
490 		/* Move relevant fragments to skb */
491 		used_frags = mlx4_en_complete_rx_desc(priv, rx_desc, skb_frags,
492 						      skb, page_alloc, length);
493 		if (unlikely(!used_frags)) {
494 			kfree_skb(skb);
495 			return NULL;
496 		}
497 		skb_shinfo(skb)->nr_frags = used_frags;
498 
499 		/* Copy headers into the skb linear buffer */
500 		memcpy(skb->data, va, HEADER_COPY_SIZE);
501 		skb->tail += HEADER_COPY_SIZE;
502 
503 		/* Skip headers in first fragment */
504 		skb_shinfo(skb)->frags[0].page_offset += HEADER_COPY_SIZE;
505 
506 		/* Adjust size of first fragment */
507 		skb_frag_size_sub(&skb_shinfo(skb)->frags[0], HEADER_COPY_SIZE);
508 		skb->data_len = length - HEADER_COPY_SIZE;
509 	}
510 	return skb;
511 }
512 
validate_loopback(struct mlx4_en_priv * priv,struct sk_buff * skb)513 static void validate_loopback(struct mlx4_en_priv *priv, struct sk_buff *skb)
514 {
515 	int i;
516 	int offset = ETH_HLEN;
517 
518 	for (i = 0; i < MLX4_LOOPBACK_TEST_PAYLOAD; i++, offset++) {
519 		if (*(skb->data + offset) != (unsigned char) (i & 0xff))
520 			goto out_loopback;
521 	}
522 	/* Loopback found */
523 	priv->loopback_ok = 1;
524 
525 out_loopback:
526 	dev_kfree_skb_any(skb);
527 }
528 
mlx4_en_process_rx_cq(struct net_device * dev,struct mlx4_en_cq * cq,int budget)529 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
530 {
531 	struct mlx4_en_priv *priv = netdev_priv(dev);
532 	struct mlx4_cqe *cqe;
533 	struct mlx4_en_rx_ring *ring = &priv->rx_ring[cq->ring];
534 	struct page_frag *skb_frags;
535 	struct mlx4_en_rx_desc *rx_desc;
536 	struct sk_buff *skb;
537 	int index;
538 	int nr;
539 	unsigned int length;
540 	int polled = 0;
541 	int ip_summed;
542 	struct ethhdr *ethh;
543 	u64 s_mac;
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 		/* Get pointer to first fragment since we haven't skb yet and
581 		 * cast it to ethhdr struct */
582 		ethh = (struct ethhdr *)(page_address(skb_frags[0].page) +
583 					 skb_frags[0].offset);
584 		s_mac = mlx4_en_mac_to_u64(ethh->h_source);
585 
586 		/* If source MAC is equal to our own MAC and not performing
587 		 * the selftest or flb disabled - drop the packet */
588 		if (s_mac == priv->mac &&
589 			(!(dev->features & NETIF_F_LOOPBACK) ||
590 			 !priv->validate_loopback))
591 			goto next;
592 
593 		/*
594 		 * Packet is OK - process it.
595 		 */
596 		length = be32_to_cpu(cqe->byte_cnt);
597 		length -= ring->fcs_del;
598 		ring->bytes += length;
599 		ring->packets++;
600 
601 		if (likely(dev->features & NETIF_F_RXCSUM)) {
602 			if ((cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPOK)) &&
603 			    (cqe->checksum == cpu_to_be16(0xffff))) {
604 				ring->csum_ok++;
605 				/* This packet is eligible for LRO if it is:
606 				 * - DIX Ethernet (type interpretation)
607 				 * - TCP/IP (v4)
608 				 * - without IP options
609 				 * - not an IP fragment */
610 				if (dev->features & NETIF_F_GRO) {
611 					struct sk_buff *gro_skb = napi_get_frags(&cq->napi);
612 					if (!gro_skb)
613 						goto next;
614 
615 					nr = mlx4_en_complete_rx_desc(
616 						priv, rx_desc,
617 						skb_frags, gro_skb,
618 						ring->page_alloc, length);
619 					if (!nr)
620 						goto next;
621 
622 					skb_shinfo(gro_skb)->nr_frags = nr;
623 					gro_skb->len = length;
624 					gro_skb->data_len = length;
625 					gro_skb->ip_summed = CHECKSUM_UNNECESSARY;
626 
627 					if (cqe->vlan_my_qpn &
628 					    cpu_to_be32(MLX4_CQE_VLAN_PRESENT_MASK)) {
629 						u16 vid = be16_to_cpu(cqe->sl_vid);
630 
631 						__vlan_hwaccel_put_tag(gro_skb, vid);
632 					}
633 
634 					if (dev->features & NETIF_F_RXHASH)
635 						gro_skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
636 
637 					skb_record_rx_queue(gro_skb, cq->ring);
638 					napi_gro_frags(&cq->napi);
639 
640 					goto next;
641 				}
642 
643 				/* LRO not possible, complete processing here */
644 				ip_summed = CHECKSUM_UNNECESSARY;
645 			} else {
646 				ip_summed = CHECKSUM_NONE;
647 				ring->csum_none++;
648 			}
649 		} else {
650 			ip_summed = CHECKSUM_NONE;
651 			ring->csum_none++;
652 		}
653 
654 		skb = mlx4_en_rx_skb(priv, rx_desc, skb_frags,
655 				     ring->page_alloc, length);
656 		if (!skb) {
657 			priv->stats.rx_dropped++;
658 			goto next;
659 		}
660 
661                 if (unlikely(priv->validate_loopback)) {
662 			validate_loopback(priv, skb);
663 			goto next;
664 		}
665 
666 		skb->ip_summed = ip_summed;
667 		skb->protocol = eth_type_trans(skb, dev);
668 		skb_record_rx_queue(skb, cq->ring);
669 
670 		if (dev->features & NETIF_F_RXHASH)
671 			skb->rxhash = be32_to_cpu(cqe->immed_rss_invalid);
672 
673 		if (be32_to_cpu(cqe->vlan_my_qpn) &
674 		    MLX4_CQE_VLAN_PRESENT_MASK)
675 			__vlan_hwaccel_put_tag(skb, be16_to_cpu(cqe->sl_vid));
676 
677 		/* Push it up the stack */
678 		netif_receive_skb(skb);
679 
680 next:
681 		++cq->mcq.cons_index;
682 		index = (cq->mcq.cons_index) & ring->size_mask;
683 		cqe = &cq->buf[index];
684 		if (++polled == budget) {
685 			/* We are here because we reached the NAPI budget -
686 			 * flush only pending LRO sessions */
687 			goto out;
688 		}
689 	}
690 
691 out:
692 	AVG_PERF_COUNTER(priv->pstats.rx_coal_avg, polled);
693 	mlx4_cq_set_ci(&cq->mcq);
694 	wmb(); /* ensure HW sees CQ consumer before we post new buffers */
695 	ring->cons = cq->mcq.cons_index;
696 	ring->prod += polled; /* Polled descriptors were realocated in place */
697 	mlx4_en_update_rx_prod_db(ring);
698 	return polled;
699 }
700 
701 
mlx4_en_rx_irq(struct mlx4_cq * mcq)702 void mlx4_en_rx_irq(struct mlx4_cq *mcq)
703 {
704 	struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
705 	struct mlx4_en_priv *priv = netdev_priv(cq->dev);
706 
707 	if (priv->port_up)
708 		napi_schedule(&cq->napi);
709 	else
710 		mlx4_en_arm_cq(priv, cq);
711 }
712 
713 /* Rx CQ polling - called by NAPI */
mlx4_en_poll_rx_cq(struct napi_struct * napi,int budget)714 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget)
715 {
716 	struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi);
717 	struct net_device *dev = cq->dev;
718 	struct mlx4_en_priv *priv = netdev_priv(dev);
719 	int done;
720 
721 	done = mlx4_en_process_rx_cq(dev, cq, budget);
722 
723 	/* If we used up all the quota - we're probably not done yet... */
724 	if (done == budget)
725 		INC_PERF_COUNTER(priv->pstats.napi_quota);
726 	else {
727 		/* Done for now */
728 		napi_complete(napi);
729 		mlx4_en_arm_cq(priv, cq);
730 	}
731 	return done;
732 }
733 
734 
735 /* Calculate the last offset position that accommodates a full fragment
736  * (assuming fagment size = stride-align) */
mlx4_en_last_alloc_offset(struct mlx4_en_priv * priv,u16 stride,u16 align)737 static int mlx4_en_last_alloc_offset(struct mlx4_en_priv *priv, u16 stride, u16 align)
738 {
739 	u16 res = MLX4_EN_ALLOC_SIZE % stride;
740 	u16 offset = MLX4_EN_ALLOC_SIZE - stride - res + align;
741 
742 	en_dbg(DRV, priv, "Calculated last offset for stride:%d align:%d "
743 			    "res:%d offset:%d\n", stride, align, res, offset);
744 	return offset;
745 }
746 
747 
748 static int frag_sizes[] = {
749 	FRAG_SZ0,
750 	FRAG_SZ1,
751 	FRAG_SZ2,
752 	FRAG_SZ3
753 };
754 
mlx4_en_calc_rx_buf(struct net_device * dev)755 void mlx4_en_calc_rx_buf(struct net_device *dev)
756 {
757 	struct mlx4_en_priv *priv = netdev_priv(dev);
758 	int eff_mtu = dev->mtu + ETH_HLEN + VLAN_HLEN + ETH_LLC_SNAP_SIZE;
759 	int buf_size = 0;
760 	int i = 0;
761 
762 	while (buf_size < eff_mtu) {
763 		priv->frag_info[i].frag_size =
764 			(eff_mtu > buf_size + frag_sizes[i]) ?
765 				frag_sizes[i] : eff_mtu - buf_size;
766 		priv->frag_info[i].frag_prefix_size = buf_size;
767 		if (!i)	{
768 			priv->frag_info[i].frag_align = NET_IP_ALIGN;
769 			priv->frag_info[i].frag_stride =
770 				ALIGN(frag_sizes[i] + NET_IP_ALIGN, SMP_CACHE_BYTES);
771 		} else {
772 			priv->frag_info[i].frag_align = 0;
773 			priv->frag_info[i].frag_stride =
774 				ALIGN(frag_sizes[i], SMP_CACHE_BYTES);
775 		}
776 		priv->frag_info[i].last_offset = mlx4_en_last_alloc_offset(
777 						priv, priv->frag_info[i].frag_stride,
778 						priv->frag_info[i].frag_align);
779 		buf_size += priv->frag_info[i].frag_size;
780 		i++;
781 	}
782 
783 	priv->num_frags = i;
784 	priv->rx_skb_size = eff_mtu;
785 	priv->log_rx_info = ROUNDUP_LOG2(i * sizeof(struct skb_frag_struct));
786 
787 	en_dbg(DRV, priv, "Rx buffer scatter-list (effective-mtu:%d "
788 		  "num_frags:%d):\n", eff_mtu, priv->num_frags);
789 	for (i = 0; i < priv->num_frags; i++) {
790 		en_dbg(DRV, priv, "  frag:%d - size:%d prefix:%d align:%d "
791 				"stride:%d last_offset:%d\n", i,
792 				priv->frag_info[i].frag_size,
793 				priv->frag_info[i].frag_prefix_size,
794 				priv->frag_info[i].frag_align,
795 				priv->frag_info[i].frag_stride,
796 				priv->frag_info[i].last_offset);
797 	}
798 }
799 
800 /* RSS related functions */
801 
mlx4_en_config_rss_qp(struct mlx4_en_priv * priv,int qpn,struct mlx4_en_rx_ring * ring,enum mlx4_qp_state * state,struct mlx4_qp * qp)802 static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
803 				 struct mlx4_en_rx_ring *ring,
804 				 enum mlx4_qp_state *state,
805 				 struct mlx4_qp *qp)
806 {
807 	struct mlx4_en_dev *mdev = priv->mdev;
808 	struct mlx4_qp_context *context;
809 	int err = 0;
810 
811 	context = kmalloc(sizeof *context , GFP_KERNEL);
812 	if (!context) {
813 		en_err(priv, "Failed to allocate qp context\n");
814 		return -ENOMEM;
815 	}
816 
817 	err = mlx4_qp_alloc(mdev->dev, qpn, qp);
818 	if (err) {
819 		en_err(priv, "Failed to allocate qp #%x\n", qpn);
820 		goto out;
821 	}
822 	qp->event = mlx4_en_sqp_event;
823 
824 	memset(context, 0, sizeof *context);
825 	mlx4_en_fill_qp_context(priv, ring->actual_size, ring->stride, 0, 0,
826 				qpn, ring->cqn, context);
827 	context->db_rec_addr = cpu_to_be64(ring->wqres.db.dma);
828 
829 	/* Cancel FCS removal if FW allows */
830 	if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
831 		context->param3 |= cpu_to_be32(1 << 29);
832 		ring->fcs_del = ETH_FCS_LEN;
833 	} else
834 		ring->fcs_del = 0;
835 
836 	err = mlx4_qp_to_ready(mdev->dev, &ring->wqres.mtt, context, qp, state);
837 	if (err) {
838 		mlx4_qp_remove(mdev->dev, qp);
839 		mlx4_qp_free(mdev->dev, qp);
840 	}
841 	mlx4_en_update_rx_prod_db(ring);
842 out:
843 	kfree(context);
844 	return err;
845 }
846 
847 /* Allocate rx qp's and configure them according to rss map */
mlx4_en_config_rss_steer(struct mlx4_en_priv * priv)848 int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
849 {
850 	struct mlx4_en_dev *mdev = priv->mdev;
851 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
852 	struct mlx4_qp_context context;
853 	struct mlx4_rss_context *rss_context;
854 	int rss_rings;
855 	void *ptr;
856 	u8 rss_mask = (MLX4_RSS_IPV4 | MLX4_RSS_TCP_IPV4 | MLX4_RSS_IPV6 |
857 			MLX4_RSS_TCP_IPV6);
858 	int i, qpn;
859 	int err = 0;
860 	int good_qps = 0;
861 	static const u32 rsskey[10] = { 0xD181C62C, 0xF7F4DB5B, 0x1983A2FC,
862 				0x943E1ADB, 0xD9389E6B, 0xD1039C2C, 0xA74499AD,
863 				0x593D56D9, 0xF3253C06, 0x2ADC1FFC};
864 
865 	en_dbg(DRV, priv, "Configuring rss steering\n");
866 	err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
867 				    priv->rx_ring_num,
868 				    &rss_map->base_qpn);
869 	if (err) {
870 		en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
871 		return err;
872 	}
873 
874 	for (i = 0; i < priv->rx_ring_num; i++) {
875 		qpn = rss_map->base_qpn + i;
876 		err = mlx4_en_config_rss_qp(priv, qpn, &priv->rx_ring[i],
877 					    &rss_map->state[i],
878 					    &rss_map->qps[i]);
879 		if (err)
880 			goto rss_err;
881 
882 		++good_qps;
883 	}
884 
885 	/* Configure RSS indirection qp */
886 	err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp);
887 	if (err) {
888 		en_err(priv, "Failed to allocate RSS indirection QP\n");
889 		goto rss_err;
890 	}
891 	rss_map->indir_qp.event = mlx4_en_sqp_event;
892 	mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
893 				priv->rx_ring[0].cqn, &context);
894 
895 	if (!priv->prof->rss_rings || priv->prof->rss_rings > priv->rx_ring_num)
896 		rss_rings = priv->rx_ring_num;
897 	else
898 		rss_rings = priv->prof->rss_rings;
899 
900 	ptr = ((void *) &context) + offsetof(struct mlx4_qp_context, pri_path)
901 					+ MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
902 	rss_context = ptr;
903 	rss_context->base_qpn = cpu_to_be32(ilog2(rss_rings) << 24 |
904 					    (rss_map->base_qpn));
905 	rss_context->default_qpn = cpu_to_be32(rss_map->base_qpn);
906 	if (priv->mdev->profile.udp_rss) {
907 		rss_mask |=  MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6;
908 		rss_context->base_qpn_udp = rss_context->default_qpn;
909 	}
910 	rss_context->flags = rss_mask;
911 	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
912 	for (i = 0; i < 10; i++)
913 		rss_context->rss_key[i] = cpu_to_be32(rsskey[i]);
914 
915 	err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
916 			       &rss_map->indir_qp, &rss_map->indir_state);
917 	if (err)
918 		goto indir_err;
919 
920 	return 0;
921 
922 indir_err:
923 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
924 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
925 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
926 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
927 rss_err:
928 	for (i = 0; i < good_qps; i++) {
929 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
930 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
931 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
932 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
933 	}
934 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
935 	return err;
936 }
937 
mlx4_en_release_rss_steer(struct mlx4_en_priv * priv)938 void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
939 {
940 	struct mlx4_en_dev *mdev = priv->mdev;
941 	struct mlx4_en_rss_map *rss_map = &priv->rss_map;
942 	int i;
943 
944 	mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
945 		       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
946 	mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
947 	mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
948 
949 	for (i = 0; i < priv->rx_ring_num; i++) {
950 		mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
951 			       MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->qps[i]);
952 		mlx4_qp_remove(mdev->dev, &rss_map->qps[i]);
953 		mlx4_qp_free(mdev->dev, &rss_map->qps[i]);
954 	}
955 	mlx4_qp_release_range(mdev->dev, rss_map->base_qpn, priv->rx_ring_num);
956 }
957 
958 
959 
960 
961 
962