xref: /dpdk/drivers/net/virtio/virtio_rxtx.c (revision 0499793854f52d0a42aa39a6b8036700f3719735)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <stdint.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <errno.h>
39 
40 #include <rte_cycles.h>
41 #include <rte_memory.h>
42 #include <rte_memzone.h>
43 #include <rte_branch_prediction.h>
44 #include <rte_mempool.h>
45 #include <rte_malloc.h>
46 #include <rte_mbuf.h>
47 #include <rte_ether.h>
48 #include <rte_ethdev.h>
49 #include <rte_prefetch.h>
50 #include <rte_string_fns.h>
51 #include <rte_errno.h>
52 #include <rte_byteorder.h>
53 
54 #include "virtio_logs.h"
55 #include "virtio_ethdev.h"
56 #include "virtio_pci.h"
57 #include "virtqueue.h"
58 #include "virtio_rxtx.h"
59 
60 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
61 #define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
62 #else
63 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
64 #endif
65 
66 
67 #define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
68 	ETH_TXQ_FLAGS_NOOFFLOADS)
69 
70 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
71 static int use_simple_rxtx;
72 #endif
73 
74 static void
75 vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
76 {
77 	struct vring_desc *dp, *dp_tail;
78 	struct vq_desc_extra *dxp;
79 	uint16_t desc_idx_last = desc_idx;
80 
81 	dp  = &vq->vq_ring.desc[desc_idx];
82 	dxp = &vq->vq_descx[desc_idx];
83 	vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
84 	if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
85 		while (dp->flags & VRING_DESC_F_NEXT) {
86 			desc_idx_last = dp->next;
87 			dp = &vq->vq_ring.desc[dp->next];
88 		}
89 	}
90 	dxp->ndescs = 0;
91 
92 	/*
93 	 * We must append the existing free chain, if any, to the end of
94 	 * newly freed chain. If the virtqueue was completely used, then
95 	 * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
96 	 */
97 	if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
98 		vq->vq_desc_head_idx = desc_idx;
99 	} else {
100 		dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
101 		dp_tail->next = desc_idx;
102 	}
103 
104 	vq->vq_desc_tail_idx = desc_idx_last;
105 	dp->next = VQ_RING_DESC_CHAIN_END;
106 }
107 
108 static uint16_t
109 virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
110 			   uint32_t *len, uint16_t num)
111 {
112 	struct vring_used_elem *uep;
113 	struct rte_mbuf *cookie;
114 	uint16_t used_idx, desc_idx;
115 	uint16_t i;
116 
117 	/*  Caller does the check */
118 	for (i = 0; i < num ; i++) {
119 		used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
120 		uep = &vq->vq_ring.used->ring[used_idx];
121 		desc_idx = (uint16_t) uep->id;
122 		len[i] = uep->len;
123 		cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
124 
125 		if (unlikely(cookie == NULL)) {
126 			PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
127 				vq->vq_used_cons_idx);
128 			break;
129 		}
130 
131 		rte_prefetch0(cookie);
132 		rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
133 		rx_pkts[i]  = cookie;
134 		vq->vq_used_cons_idx++;
135 		vq_ring_free_chain(vq, desc_idx);
136 		vq->vq_descx[desc_idx].cookie = NULL;
137 	}
138 
139 	return i;
140 }
141 
142 #ifndef DEFAULT_TX_FREE_THRESH
143 #define DEFAULT_TX_FREE_THRESH 32
144 #endif
145 
146 /* Cleanup from completed transmits. */
147 static void
148 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
149 {
150 	uint16_t i, used_idx, desc_idx;
151 	for (i = 0; i < num; i++) {
152 		struct vring_used_elem *uep;
153 		struct vq_desc_extra *dxp;
154 
155 		used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
156 		uep = &vq->vq_ring.used->ring[used_idx];
157 
158 		desc_idx = (uint16_t) uep->id;
159 		dxp = &vq->vq_descx[desc_idx];
160 		vq->vq_used_cons_idx++;
161 		vq_ring_free_chain(vq, desc_idx);
162 
163 		if (dxp->cookie != NULL) {
164 			rte_pktmbuf_free(dxp->cookie);
165 			dxp->cookie = NULL;
166 		}
167 	}
168 }
169 
170 
171 static inline int
172 virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
173 {
174 	struct vq_desc_extra *dxp;
175 	struct virtio_hw *hw = vq->hw;
176 	struct vring_desc *start_dp;
177 	uint16_t needed = 1;
178 	uint16_t head_idx, idx;
179 
180 	if (unlikely(vq->vq_free_cnt == 0))
181 		return -ENOSPC;
182 	if (unlikely(vq->vq_free_cnt < needed))
183 		return -EMSGSIZE;
184 
185 	head_idx = vq->vq_desc_head_idx;
186 	if (unlikely(head_idx >= vq->vq_nentries))
187 		return -EFAULT;
188 
189 	idx = head_idx;
190 	dxp = &vq->vq_descx[idx];
191 	dxp->cookie = (void *)cookie;
192 	dxp->ndescs = needed;
193 
194 	start_dp = vq->vq_ring.desc;
195 	start_dp[idx].addr =
196 		(uint64_t)(cookie->buf_physaddr + RTE_PKTMBUF_HEADROOM
197 		- hw->vtnet_hdr_size);
198 	start_dp[idx].len =
199 		cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
200 	start_dp[idx].flags =  VRING_DESC_F_WRITE;
201 	idx = start_dp[idx].next;
202 	vq->vq_desc_head_idx = idx;
203 	if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
204 		vq->vq_desc_tail_idx = idx;
205 	vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
206 	vq_update_avail_ring(vq, head_idx);
207 
208 	return 0;
209 }
210 
211 static inline void
212 virtqueue_enqueue_xmit(struct virtqueue *txvq, struct rte_mbuf *cookie,
213 		       uint16_t needed, int use_indirect, int can_push)
214 {
215 	struct vq_desc_extra *dxp;
216 	struct vring_desc *start_dp;
217 	uint16_t seg_num = cookie->nb_segs;
218 	uint16_t head_idx, idx;
219 	uint16_t head_size = txvq->hw->vtnet_hdr_size;
220 	unsigned long offs;
221 
222 	head_idx = txvq->vq_desc_head_idx;
223 	idx = head_idx;
224 	dxp = &txvq->vq_descx[idx];
225 	dxp->cookie = (void *)cookie;
226 	dxp->ndescs = needed;
227 
228 	start_dp = txvq->vq_ring.desc;
229 
230 	if (can_push) {
231 		/* put on zero'd transmit header (no offloads) */
232 		void *hdr = rte_pktmbuf_prepend(cookie, head_size);
233 
234 		memset(hdr, 0, head_size);
235 	} else if (use_indirect) {
236 		/* setup tx ring slot to point to indirect
237 		 * descriptor list stored in reserved region.
238 		 *
239 		 * the first slot in indirect ring is already preset
240 		 * to point to the header in reserved region
241 		 */
242 		struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
243 
244 		offs = idx * sizeof(struct virtio_tx_region)
245 			+ offsetof(struct virtio_tx_region, tx_indir);
246 
247 		start_dp[idx].addr  = txvq->virtio_net_hdr_mem + offs;
248 		start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
249 		start_dp[idx].flags = VRING_DESC_F_INDIRECT;
250 
251 		/* loop below will fill in rest of the indirect elements */
252 		start_dp = txr[idx].tx_indir;
253 		idx = 1;
254 	} else {
255 		/* setup first tx ring slot to point to header
256 		 * stored in reserved region.
257 		 */
258 		offs = idx * sizeof(struct virtio_tx_region)
259 			+ offsetof(struct virtio_tx_region, tx_hdr);
260 
261 		start_dp[idx].addr  = txvq->virtio_net_hdr_mem + offs;
262 		start_dp[idx].len   = txvq->hw->vtnet_hdr_size;
263 		start_dp[idx].flags = VRING_DESC_F_NEXT;
264 		idx = start_dp[idx].next;
265 	}
266 
267 	do {
268 		start_dp[idx].addr  = rte_mbuf_data_dma_addr(cookie);
269 		start_dp[idx].len   = cookie->data_len;
270 		start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
271 		idx = start_dp[idx].next;
272 	} while ((cookie = cookie->next) != NULL);
273 
274 	if (use_indirect)
275 		idx = txvq->vq_ring.desc[head_idx].next;
276 
277 	txvq->vq_desc_head_idx = idx;
278 	if (txvq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
279 		txvq->vq_desc_tail_idx = idx;
280 	txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
281 	vq_update_avail_ring(txvq, head_idx);
282 }
283 
284 static void
285 virtio_dev_vring_start(struct virtqueue *vq, int queue_type)
286 {
287 	struct rte_mbuf *m;
288 	int i, nbufs, error, size = vq->vq_nentries;
289 	struct vring *vr = &vq->vq_ring;
290 	uint8_t *ring_mem = vq->vq_ring_virt_mem;
291 
292 	PMD_INIT_FUNC_TRACE();
293 
294 	/*
295 	 * Reinitialise since virtio port might have been stopped and restarted
296 	 */
297 	memset(vq->vq_ring_virt_mem, 0, vq->vq_ring_size);
298 	vring_init(vr, size, ring_mem, VIRTIO_PCI_VRING_ALIGN);
299 	vq->vq_used_cons_idx = 0;
300 	vq->vq_desc_head_idx = 0;
301 	vq->vq_avail_idx = 0;
302 	vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
303 	vq->vq_free_cnt = vq->vq_nentries;
304 	memset(vq->vq_descx, 0, sizeof(struct vq_desc_extra) * vq->vq_nentries);
305 
306 	vring_desc_init(vr->desc, size);
307 
308 	/*
309 	 * Disable device(host) interrupting guest
310 	 */
311 	virtqueue_disable_intr(vq);
312 
313 	/* Only rx virtqueue needs mbufs to be allocated at initialization */
314 	if (queue_type == VTNET_RQ) {
315 		if (vq->mpool == NULL)
316 			rte_exit(EXIT_FAILURE,
317 			"Cannot allocate initial mbufs for rx virtqueue");
318 
319 		/* Allocate blank mbufs for the each rx descriptor */
320 		nbufs = 0;
321 		error = ENOSPC;
322 
323 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
324 		if (use_simple_rxtx)
325 			for (i = 0; i < vq->vq_nentries; i++) {
326 				vq->vq_ring.avail->ring[i] = i;
327 				vq->vq_ring.desc[i].flags = VRING_DESC_F_WRITE;
328 			}
329 #endif
330 		memset(&vq->fake_mbuf, 0, sizeof(vq->fake_mbuf));
331 		for (i = 0; i < RTE_PMD_VIRTIO_RX_MAX_BURST; i++)
332 			vq->sw_ring[vq->vq_nentries + i] = &vq->fake_mbuf;
333 
334 		while (!virtqueue_full(vq)) {
335 			m = rte_mbuf_raw_alloc(vq->mpool);
336 			if (m == NULL)
337 				break;
338 
339 			/******************************************
340 			*         Enqueue allocated buffers        *
341 			*******************************************/
342 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
343 			if (use_simple_rxtx)
344 				error = virtqueue_enqueue_recv_refill_simple(vq, m);
345 			else
346 #endif
347 				error = virtqueue_enqueue_recv_refill(vq, m);
348 			if (error) {
349 				rte_pktmbuf_free(m);
350 				break;
351 			}
352 			nbufs++;
353 		}
354 
355 		vq_update_avail_idx(vq);
356 
357 		PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
358 	} else if (queue_type == VTNET_TQ) {
359 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
360 		if (use_simple_rxtx) {
361 			int mid_idx  = vq->vq_nentries >> 1;
362 			for (i = 0; i < mid_idx; i++) {
363 				vq->vq_ring.avail->ring[i] = i + mid_idx;
364 				vq->vq_ring.desc[i + mid_idx].next = i;
365 				vq->vq_ring.desc[i + mid_idx].addr =
366 					vq->virtio_net_hdr_mem +
367 					offsetof(struct virtio_tx_region, tx_hdr);
368 				vq->vq_ring.desc[i + mid_idx].len =
369 					vq->hw->vtnet_hdr_size;
370 				vq->vq_ring.desc[i + mid_idx].flags =
371 					VRING_DESC_F_NEXT;
372 				vq->vq_ring.desc[i].flags = 0;
373 			}
374 			for (i = mid_idx; i < vq->vq_nentries; i++)
375 				vq->vq_ring.avail->ring[i] = i;
376 		}
377 #endif
378 	}
379 }
380 
381 void
382 virtio_dev_cq_start(struct rte_eth_dev *dev)
383 {
384 	struct virtio_hw *hw = dev->data->dev_private;
385 
386 	if (hw->cvq) {
387 		virtio_dev_vring_start(hw->cvq, VTNET_CQ);
388 		VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq);
389 	}
390 }
391 
392 void
393 virtio_dev_rxtx_start(struct rte_eth_dev *dev)
394 {
395 	/*
396 	 * Start receive and transmit vrings
397 	 * -	Setup vring structure for all queues
398 	 * -	Initialize descriptor for the rx vring
399 	 * -	Allocate blank mbufs for the each rx descriptor
400 	 *
401 	 */
402 	int i;
403 
404 	PMD_INIT_FUNC_TRACE();
405 
406 	/* Start rx vring. */
407 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
408 		virtio_dev_vring_start(dev->data->rx_queues[i], VTNET_RQ);
409 		VIRTQUEUE_DUMP((struct virtqueue *)dev->data->rx_queues[i]);
410 	}
411 
412 	/* Start tx vring. */
413 	for (i = 0; i < dev->data->nb_tx_queues; i++) {
414 		virtio_dev_vring_start(dev->data->tx_queues[i], VTNET_TQ);
415 		VIRTQUEUE_DUMP((struct virtqueue *)dev->data->tx_queues[i]);
416 	}
417 }
418 
419 int
420 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
421 			uint16_t queue_idx,
422 			uint16_t nb_desc,
423 			unsigned int socket_id,
424 			__rte_unused const struct rte_eth_rxconf *rx_conf,
425 			struct rte_mempool *mp)
426 {
427 	uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
428 	struct virtqueue *vq;
429 	int ret;
430 
431 	PMD_INIT_FUNC_TRACE();
432 	ret = virtio_dev_queue_setup(dev, VTNET_RQ, queue_idx, vtpci_queue_idx,
433 			nb_desc, socket_id, &vq);
434 	if (ret < 0) {
435 		PMD_INIT_LOG(ERR, "rvq initialization failed");
436 		return ret;
437 	}
438 
439 	/* Create mempool for rx mbuf allocation */
440 	vq->mpool = mp;
441 
442 	dev->data->rx_queues[queue_idx] = vq;
443 
444 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
445 	virtio_rxq_vec_setup(vq);
446 #endif
447 
448 	return 0;
449 }
450 
451 void
452 virtio_dev_rx_queue_release(void *rxq)
453 {
454 	virtio_dev_queue_release(rxq);
455 }
456 
457 /*
458  * struct rte_eth_dev *dev: Used to update dev
459  * uint16_t nb_desc: Defaults to values read from config space
460  * unsigned int socket_id: Used to allocate memzone
461  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
462  * uint16_t queue_idx: Just used as an index in dev txq list
463  */
464 int
465 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
466 			uint16_t queue_idx,
467 			uint16_t nb_desc,
468 			unsigned int socket_id,
469 			const struct rte_eth_txconf *tx_conf)
470 {
471 	uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
472 
473 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
474 	struct virtio_hw *hw = dev->data->dev_private;
475 #endif
476 	struct virtqueue *vq;
477 	uint16_t tx_free_thresh;
478 	int ret;
479 
480 	PMD_INIT_FUNC_TRACE();
481 
482 	if ((tx_conf->txq_flags & ETH_TXQ_FLAGS_NOXSUMS)
483 	    != ETH_TXQ_FLAGS_NOXSUMS) {
484 		PMD_INIT_LOG(ERR, "TX checksum offload not supported\n");
485 		return -EINVAL;
486 	}
487 
488 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
489 	/* Use simple rx/tx func if single segment and no offloads */
490 	if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
491 	     !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
492 		PMD_INIT_LOG(INFO, "Using simple rx/tx path");
493 		dev->tx_pkt_burst = virtio_xmit_pkts_simple;
494 		dev->rx_pkt_burst = virtio_recv_pkts_vec;
495 		use_simple_rxtx = 1;
496 	}
497 #endif
498 
499 	ret = virtio_dev_queue_setup(dev, VTNET_TQ, queue_idx, vtpci_queue_idx,
500 			nb_desc, socket_id, &vq);
501 	if (ret < 0) {
502 		PMD_INIT_LOG(ERR, "rvq initialization failed");
503 		return ret;
504 	}
505 
506 	tx_free_thresh = tx_conf->tx_free_thresh;
507 	if (tx_free_thresh == 0)
508 		tx_free_thresh =
509 			RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
510 
511 	if (tx_free_thresh >= (vq->vq_nentries - 3)) {
512 		RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
513 			"number of TX entries minus 3 (%u)."
514 			" (tx_free_thresh=%u port=%u queue=%u)\n",
515 			vq->vq_nentries - 3,
516 			tx_free_thresh, dev->data->port_id, queue_idx);
517 		return -EINVAL;
518 	}
519 
520 	vq->vq_free_thresh = tx_free_thresh;
521 
522 	dev->data->tx_queues[queue_idx] = vq;
523 	return 0;
524 }
525 
526 void
527 virtio_dev_tx_queue_release(void *txq)
528 {
529 	virtio_dev_queue_release(txq);
530 }
531 
532 static void
533 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
534 {
535 	int error;
536 	/*
537 	 * Requeue the discarded mbuf. This should always be
538 	 * successful since it was just dequeued.
539 	 */
540 	error = virtqueue_enqueue_recv_refill(vq, m);
541 	if (unlikely(error)) {
542 		RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
543 		rte_pktmbuf_free(m);
544 	}
545 }
546 
547 static void
548 virtio_update_packet_stats(struct virtqueue *vq, struct rte_mbuf *mbuf)
549 {
550 	uint32_t s = mbuf->pkt_len;
551 	struct ether_addr *ea;
552 
553 	if (s == 64) {
554 		vq->size_bins[1]++;
555 	} else if (s > 64 && s < 1024) {
556 		uint32_t bin;
557 
558 		/* count zeros, and offset into correct bin */
559 		bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
560 		vq->size_bins[bin]++;
561 	} else {
562 		if (s < 64)
563 			vq->size_bins[0]++;
564 		else if (s < 1519)
565 			vq->size_bins[6]++;
566 		else if (s >= 1519)
567 			vq->size_bins[7]++;
568 	}
569 
570 	ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
571 	if (is_multicast_ether_addr(ea)) {
572 		if (is_broadcast_ether_addr(ea))
573 			vq->broadcast++;
574 		else
575 			vq->multicast++;
576 	}
577 }
578 
579 #define VIRTIO_MBUF_BURST_SZ 64
580 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
581 uint16_t
582 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
583 {
584 	struct virtqueue *rxvq = rx_queue;
585 	struct virtio_hw *hw;
586 	struct rte_mbuf *rxm, *new_mbuf;
587 	uint16_t nb_used, num, nb_rx;
588 	uint32_t len[VIRTIO_MBUF_BURST_SZ];
589 	struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
590 	int error;
591 	uint32_t i, nb_enqueued;
592 	uint32_t hdr_size;
593 
594 	nb_used = VIRTQUEUE_NUSED(rxvq);
595 
596 	virtio_rmb();
597 
598 	num = (uint16_t)(likely(nb_used <= nb_pkts) ? nb_used : nb_pkts);
599 	num = (uint16_t)(likely(num <= VIRTIO_MBUF_BURST_SZ) ? num : VIRTIO_MBUF_BURST_SZ);
600 	if (likely(num > DESC_PER_CACHELINE))
601 		num = num - ((rxvq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
602 
603 	num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, num);
604 	PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
605 
606 	hw = rxvq->hw;
607 	nb_rx = 0;
608 	nb_enqueued = 0;
609 	hdr_size = hw->vtnet_hdr_size;
610 
611 	for (i = 0; i < num ; i++) {
612 		rxm = rcv_pkts[i];
613 
614 		PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
615 
616 		if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
617 			PMD_RX_LOG(ERR, "Packet drop");
618 			nb_enqueued++;
619 			virtio_discard_rxbuf(rxvq, rxm);
620 			rxvq->errors++;
621 			continue;
622 		}
623 
624 		rxm->port = rxvq->port_id;
625 		rxm->data_off = RTE_PKTMBUF_HEADROOM;
626 		rxm->ol_flags = 0;
627 		rxm->vlan_tci = 0;
628 
629 		rxm->nb_segs = 1;
630 		rxm->next = NULL;
631 		rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
632 		rxm->data_len = (uint16_t)(len[i] - hdr_size);
633 
634 		if (hw->vlan_strip)
635 			rte_vlan_strip(rxm);
636 
637 		VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
638 
639 		rx_pkts[nb_rx++] = rxm;
640 
641 		rxvq->bytes += rx_pkts[nb_rx - 1]->pkt_len;
642 		virtio_update_packet_stats(rxvq, rxm);
643 	}
644 
645 	rxvq->packets += nb_rx;
646 
647 	/* Allocate new mbuf for the used descriptor */
648 	error = ENOSPC;
649 	while (likely(!virtqueue_full(rxvq))) {
650 		new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
651 		if (unlikely(new_mbuf == NULL)) {
652 			struct rte_eth_dev *dev
653 				= &rte_eth_devices[rxvq->port_id];
654 			dev->data->rx_mbuf_alloc_failed++;
655 			break;
656 		}
657 		error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
658 		if (unlikely(error)) {
659 			rte_pktmbuf_free(new_mbuf);
660 			break;
661 		}
662 		nb_enqueued++;
663 	}
664 
665 	if (likely(nb_enqueued)) {
666 		vq_update_avail_idx(rxvq);
667 
668 		if (unlikely(virtqueue_kick_prepare(rxvq))) {
669 			virtqueue_notify(rxvq);
670 			PMD_RX_LOG(DEBUG, "Notified");
671 		}
672 	}
673 
674 	return nb_rx;
675 }
676 
677 uint16_t
678 virtio_recv_mergeable_pkts(void *rx_queue,
679 			struct rte_mbuf **rx_pkts,
680 			uint16_t nb_pkts)
681 {
682 	struct virtqueue *rxvq = rx_queue;
683 	struct virtio_hw *hw;
684 	struct rte_mbuf *rxm, *new_mbuf;
685 	uint16_t nb_used, num, nb_rx;
686 	uint32_t len[VIRTIO_MBUF_BURST_SZ];
687 	struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
688 	struct rte_mbuf *prev;
689 	int error;
690 	uint32_t i, nb_enqueued;
691 	uint32_t seg_num;
692 	uint16_t extra_idx;
693 	uint32_t seg_res;
694 	uint32_t hdr_size;
695 
696 	nb_used = VIRTQUEUE_NUSED(rxvq);
697 
698 	virtio_rmb();
699 
700 	PMD_RX_LOG(DEBUG, "used:%d", nb_used);
701 
702 	hw = rxvq->hw;
703 	nb_rx = 0;
704 	i = 0;
705 	nb_enqueued = 0;
706 	seg_num = 0;
707 	extra_idx = 0;
708 	seg_res = 0;
709 	hdr_size = hw->vtnet_hdr_size;
710 
711 	while (i < nb_used) {
712 		struct virtio_net_hdr_mrg_rxbuf *header;
713 
714 		if (nb_rx == nb_pkts)
715 			break;
716 
717 		num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, 1);
718 		if (num != 1)
719 			continue;
720 
721 		i++;
722 
723 		PMD_RX_LOG(DEBUG, "dequeue:%d", num);
724 		PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
725 
726 		rxm = rcv_pkts[0];
727 
728 		if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
729 			PMD_RX_LOG(ERR, "Packet drop");
730 			nb_enqueued++;
731 			virtio_discard_rxbuf(rxvq, rxm);
732 			rxvq->errors++;
733 			continue;
734 		}
735 
736 		header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
737 			RTE_PKTMBUF_HEADROOM - hdr_size);
738 		seg_num = header->num_buffers;
739 
740 		if (seg_num == 0)
741 			seg_num = 1;
742 
743 		rxm->data_off = RTE_PKTMBUF_HEADROOM;
744 		rxm->nb_segs = seg_num;
745 		rxm->next = NULL;
746 		rxm->ol_flags = 0;
747 		rxm->vlan_tci = 0;
748 		rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
749 		rxm->data_len = (uint16_t)(len[0] - hdr_size);
750 
751 		rxm->port = rxvq->port_id;
752 		rx_pkts[nb_rx] = rxm;
753 		prev = rxm;
754 
755 		seg_res = seg_num - 1;
756 
757 		while (seg_res != 0) {
758 			/*
759 			 * Get extra segments for current uncompleted packet.
760 			 */
761 			uint16_t  rcv_cnt =
762 				RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
763 			if (likely(VIRTQUEUE_NUSED(rxvq) >= rcv_cnt)) {
764 				uint32_t rx_num =
765 					virtqueue_dequeue_burst_rx(rxvq,
766 					rcv_pkts, len, rcv_cnt);
767 				i += rx_num;
768 				rcv_cnt = rx_num;
769 			} else {
770 				PMD_RX_LOG(ERR,
771 					   "No enough segments for packet.");
772 				nb_enqueued++;
773 				virtio_discard_rxbuf(rxvq, rxm);
774 				rxvq->errors++;
775 				break;
776 			}
777 
778 			extra_idx = 0;
779 
780 			while (extra_idx < rcv_cnt) {
781 				rxm = rcv_pkts[extra_idx];
782 
783 				rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
784 				rxm->next = NULL;
785 				rxm->pkt_len = (uint32_t)(len[extra_idx]);
786 				rxm->data_len = (uint16_t)(len[extra_idx]);
787 
788 				if (prev)
789 					prev->next = rxm;
790 
791 				prev = rxm;
792 				rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
793 				extra_idx++;
794 			};
795 			seg_res -= rcv_cnt;
796 		}
797 
798 		if (hw->vlan_strip)
799 			rte_vlan_strip(rx_pkts[nb_rx]);
800 
801 		VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
802 			rx_pkts[nb_rx]->data_len);
803 
804 		rxvq->bytes += rx_pkts[nb_rx]->pkt_len;
805 		virtio_update_packet_stats(rxvq, rx_pkts[nb_rx]);
806 		nb_rx++;
807 	}
808 
809 	rxvq->packets += nb_rx;
810 
811 	/* Allocate new mbuf for the used descriptor */
812 	error = ENOSPC;
813 	while (likely(!virtqueue_full(rxvq))) {
814 		new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
815 		if (unlikely(new_mbuf == NULL)) {
816 			struct rte_eth_dev *dev
817 				= &rte_eth_devices[rxvq->port_id];
818 			dev->data->rx_mbuf_alloc_failed++;
819 			break;
820 		}
821 		error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
822 		if (unlikely(error)) {
823 			rte_pktmbuf_free(new_mbuf);
824 			break;
825 		}
826 		nb_enqueued++;
827 	}
828 
829 	if (likely(nb_enqueued)) {
830 		vq_update_avail_idx(rxvq);
831 
832 		if (unlikely(virtqueue_kick_prepare(rxvq))) {
833 			virtqueue_notify(rxvq);
834 			PMD_RX_LOG(DEBUG, "Notified");
835 		}
836 	}
837 
838 	return nb_rx;
839 }
840 
841 uint16_t
842 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
843 {
844 	struct virtqueue *txvq = tx_queue;
845 	struct virtio_hw *hw = txvq->hw;
846 	uint16_t hdr_size = hw->vtnet_hdr_size;
847 	uint16_t nb_used, nb_tx;
848 	int error;
849 
850 	if (unlikely(nb_pkts < 1))
851 		return nb_pkts;
852 
853 	PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
854 	nb_used = VIRTQUEUE_NUSED(txvq);
855 
856 	virtio_rmb();
857 	if (likely(nb_used > txvq->vq_nentries - txvq->vq_free_thresh))
858 		virtio_xmit_cleanup(txvq, nb_used);
859 
860 	for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
861 		struct rte_mbuf *txm = tx_pkts[nb_tx];
862 		int can_push = 0, use_indirect = 0, slots, need;
863 
864 		/* Do VLAN tag insertion */
865 		if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
866 			error = rte_vlan_insert(&txm);
867 			if (unlikely(error)) {
868 				rte_pktmbuf_free(txm);
869 				continue;
870 			}
871 		}
872 
873 		/* optimize ring usage */
874 		if (vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) &&
875 		    rte_mbuf_refcnt_read(txm) == 1 &&
876 		    txm->nb_segs == 1 &&
877 		    rte_pktmbuf_headroom(txm) >= hdr_size &&
878 		    rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
879 				   __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
880 			can_push = 1;
881 		else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
882 			 txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
883 			use_indirect = 1;
884 
885 		/* How many main ring entries are needed to this Tx?
886 		 * any_layout => number of segments
887 		 * indirect   => 1
888 		 * default    => number of segments + 1
889 		 */
890 		slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
891 		need = slots - txvq->vq_free_cnt;
892 
893 		/* Positive value indicates it need free vring descriptors */
894 		if (unlikely(need > 0)) {
895 			nb_used = VIRTQUEUE_NUSED(txvq);
896 			virtio_rmb();
897 			need = RTE_MIN(need, (int)nb_used);
898 
899 			virtio_xmit_cleanup(txvq, need);
900 			need = slots - txvq->vq_free_cnt;
901 			if (unlikely(need > 0)) {
902 				PMD_TX_LOG(ERR,
903 					   "No free tx descriptors to transmit");
904 				break;
905 			}
906 		}
907 
908 		/* Enqueue Packet buffers */
909 		virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
910 
911 		txvq->bytes += txm->pkt_len;
912 		virtio_update_packet_stats(txvq, txm);
913 	}
914 
915 	txvq->packets += nb_tx;
916 
917 	if (likely(nb_tx)) {
918 		vq_update_avail_idx(txvq);
919 
920 		if (unlikely(virtqueue_kick_prepare(txvq))) {
921 			virtqueue_notify(txvq);
922 			PMD_TX_LOG(DEBUG, "Notified backend after xmit");
923 		}
924 	}
925 
926 	return nb_tx;
927 }
928