1/*-
2 *   BSD LICENSE
3 *
4 *   Copyright(c) 2010-2015 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_rxtx_simple.h"
55
56#ifndef __INTEL_COMPILER
57#pragma GCC diagnostic ignored "-Wcast-qual"
58#endif
59
60uint16_t
61virtio_xmit_pkts_simple(void *tx_queue, struct rte_mbuf **tx_pkts,
62	uint16_t nb_pkts)
63{
64	struct virtnet_tx *txvq = tx_queue;
65	struct virtqueue *vq = txvq->vq;
66	uint16_t nb_used;
67	uint16_t desc_idx;
68	struct vring_desc *start_dp;
69	uint16_t nb_tail, nb_commit;
70	int i;
71	uint16_t desc_idx_max = (vq->vq_nentries >> 1) - 1;
72
73	nb_used = VIRTQUEUE_NUSED(vq);
74	rte_compiler_barrier();
75
76	if (nb_used >= VIRTIO_TX_FREE_THRESH)
77		virtio_xmit_cleanup_simple(vq);
78
79	nb_commit = nb_pkts = RTE_MIN((vq->vq_free_cnt >> 1), nb_pkts);
80	desc_idx = (uint16_t)(vq->vq_avail_idx & desc_idx_max);
81	start_dp = vq->vq_ring.desc;
82	nb_tail = (uint16_t) (desc_idx_max + 1 - desc_idx);
83
84	if (nb_commit >= nb_tail) {
85		for (i = 0; i < nb_tail; i++)
86			vq->vq_descx[desc_idx + i].cookie = tx_pkts[i];
87		for (i = 0; i < nb_tail; i++) {
88			start_dp[desc_idx].addr =
89				VIRTIO_MBUF_DATA_DMA_ADDR(*tx_pkts, vq);
90			start_dp[desc_idx].len = (*tx_pkts)->pkt_len;
91			tx_pkts++;
92			desc_idx++;
93		}
94		nb_commit -= nb_tail;
95		desc_idx = 0;
96	}
97	for (i = 0; i < nb_commit; i++)
98		vq->vq_descx[desc_idx + i].cookie = tx_pkts[i];
99	for (i = 0; i < nb_commit; i++) {
100		start_dp[desc_idx].addr =
101			VIRTIO_MBUF_DATA_DMA_ADDR(*tx_pkts, vq);
102		start_dp[desc_idx].len = (*tx_pkts)->pkt_len;
103		tx_pkts++;
104		desc_idx++;
105	}
106
107	rte_compiler_barrier();
108
109	vq->vq_free_cnt -= (uint16_t)(nb_pkts << 1);
110	vq->vq_avail_idx += nb_pkts;
111	vq->vq_ring.avail->idx = vq->vq_avail_idx;
112	txvq->stats.packets += nb_pkts;
113
114	if (likely(nb_pkts)) {
115		if (unlikely(virtqueue_kick_prepare(vq)))
116			virtqueue_notify(vq);
117	}
118
119	return nb_pkts;
120}
121
122int __attribute__((cold))
123virtio_rxq_vec_setup(struct virtnet_rx *rxq)
124{
125	uintptr_t p;
126	struct rte_mbuf mb_def = { .buf_addr = 0 }; /* zeroed mbuf */
127
128	mb_def.nb_segs = 1;
129	mb_def.data_off = RTE_PKTMBUF_HEADROOM;
130	mb_def.port = rxq->port_id;
131	rte_mbuf_refcnt_set(&mb_def, 1);
132
133	/* prevent compiler reordering: rearm_data covers previous fields */
134	rte_compiler_barrier();
135	p = (uintptr_t)&mb_def.rearm_data;
136	rxq->mbuf_initializer = *(uint64_t *)p;
137
138	return 0;
139}
140
141/* Stub for linkage when arch specific implementation is not available */
142uint16_t __attribute__((weak))
143virtio_recv_pkts_vec(void *rx_queue __rte_unused,
144		     struct rte_mbuf **rx_pkts __rte_unused,
145		     uint16_t nb_pkts __rte_unused)
146{
147	rte_panic("Wrong weak function linked by linker\n");
148	return 0;
149}
150