/*-
* BSD LICENSE
*
* Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _VIRTQUEUE_H_
#define _VIRTQUEUE_H_
#include <stdint.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_net.h>
#include <rte_atomic.h>
#include <rte_memory.h>
#include <rte_memzone.h>
#include <rte_mempool.h>
#include "virtio_logs.h"
struct rte_mbuf;
/* The alignment to use between consumer and producer parts of vring. */
#define VIRTIO_PCI_VRING_ALIGN 4096
enum { VTNET_RQ = 0, VTNET_TQ = 1, VTNET_CQ = 2 };
/**
* The maximum virtqueue size is 2^15. Use that value as the end of
* descriptor chain terminator since it will never be a valid index
* in the descriptor table. This is used to verify we are correctly
* handling vq_free_cnt.
*/
#define VQ_RING_DESC_CHAIN_END 32768
#define VIRTQUEUE_MAX_NAME_SZ 32
struct pmd_internals {
struct rte_eth_stats eth_stats;
int port_id;
int virtio_idx;
};
struct virtqueue {
char vq_name[VIRTQUEUE_MAX_NAME_SZ];
struct rte_mempool *mpool; /**< mempool for mbuf allocation */
uint16_t queue_id; /**< DPDK queue index. */
uint16_t vq_queue_index; /**< PCI queue index */
uint8_t port_id; /**< Device port identifier. */
void *vq_ring_virt_mem; /**< virtual address of vring*/
int vq_alignment;
int vq_ring_size;
struct vring vq_ring; /**< vring keeping desc, used and avail */
struct pmd_internals *internals; /**< virtio device internal info. */
uint16_t vq_nentries; /**< vring desc numbers */
uint16_t vq_desc_head_idx;
uint16_t vq_free_cnt; /**< num of desc available */
uint16_t vq_used_cons_idx; /**< Last consumed desc in used table, trails vq_ring.used->idx*/
struct vq_desc_extra {
void *cookie;
uint16_t ndescs;
} vq_descx[0] __rte_cache_aligned;
};
#ifdef RTE_LIBRTE_XENVIRT_DEBUG_DUMP
#define VIRTQUEUE_DUMP(vq) do { \
uint16_t used_idx, nused; \
used_idx = (vq)->vq_ring.used->idx; \
nused = (uint16_t)(used_idx - (vq)->vq_used_cons_idx); \
PMD_INIT_LOG(DEBUG, \
"VQ: %s - size=%d; free=%d; used=%d; desc_head_idx=%d;" \
" avail.idx=%d; used_cons_idx=%d; used.idx=%d;" \
" avail.flags=0x%x; used.flags=0x%x\n", \
(vq)->vq_name, (vq)->vq_nentries, (vq)->vq_free_cnt, nused, \
(vq)->vq_desc_head_idx, (vq)->vq_ring.avail->idx, \
(vq)->vq_used_cons_idx, (vq)->vq_ring.used->idx, \
(vq)->vq_ring.avail->flags, (vq)->vq_ring.used->flags); \
} while (0)
#else
#define VIRTQUEUE_DUMP(vq) do { } while (0)
#endif
/**
* Dump virtqueue internal structures, for debug purpose only.
*/
void virtqueue_dump(struct virtqueue *vq);
/**
* Get all mbufs to be freed.
*/
struct rte_mbuf * virtqueue_detatch_unused(struct virtqueue *vq);
static inline int __attribute__((always_inline))
virtqueue_full(const struct virtqueue *vq)
{
return vq->vq_free_cnt == 0;
}
#define VIRTQUEUE_NUSED(vq) ((uint16_t)((vq)->vq_ring.used->idx - (vq)->vq_used_cons_idx))
static inline void __attribute__((always_inline))
vq_ring_update_avail(struct virtqueue *vq, uint16_t desc_idx)
{
uint16_t avail_idx;
/*
* Place the head of the descriptor chain into the next slot and make
* it usable to the host. The chain is made available now rather than
* deferring to virtqueue_notify() in the hopes that if the host is
* currently running on another CPU, we can keep it processing the new
* descriptor.
*/
avail_idx = (uint16_t)(vq->vq_ring.avail->idx & (vq->vq_nentries - 1));
vq->vq_ring.avail->ring[avail_idx] = desc_idx;
rte_smp_wmb();
vq->vq_ring.avail->idx++;
}
static inline void __attribute__((always_inline))
vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
{
struct vring_desc *dp;
struct vq_desc_extra *dxp;
dp = &vq->vq_ring.desc[desc_idx];
dxp = &vq->vq_descx[desc_idx];
vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
while (dp->flags & VRING_DESC_F_NEXT) {
dp = &vq->vq_ring.desc[dp->next];
}
dxp->ndescs = 0;
/*
* We must append the existing free chain, if any, to the end of
* newly freed chain. If the virtqueue was completely used, then
* head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
*/
dp->next = vq->vq_desc_head_idx;
vq->vq_desc_head_idx = desc_idx;
}
static inline int __attribute__((always_inline))
virtqueue_enqueue_recv_refill(struct virtqueue *rxvq, struct rte_mbuf *cookie)
{
const uint16_t needed = 1;
const uint16_t head_idx = rxvq->vq_desc_head_idx;
struct vring_desc *start_dp = rxvq->vq_ring.desc;
struct vq_desc_extra *dxp;
if (unlikely(rxvq->vq_free_cnt == 0))
return -ENOSPC;
if (unlikely(rxvq->vq_free_cnt < needed))
return -EMSGSIZE;
if (unlikely(head_idx >= rxvq->vq_nentries))
return -EFAULT;
dxp = &rxvq->vq_descx[head_idx];
dxp->cookie = (void *)cookie;
dxp->ndescs = needed;
start_dp[head_idx].addr =
(uint64_t) ((uintptr_t)cookie->buf_addr + RTE_PKTMBUF_HEADROOM - sizeof(struct virtio_net_hdr));
start_dp[head_idx].len = cookie->buf_len - RTE_PKTMBUF_HEADROOM + sizeof(struct virtio_net_hdr);
start_dp[head_idx].flags = VRING_DESC_F_WRITE;
rxvq->vq_desc_head_idx = start_dp[head_idx].next;
rxvq->vq_free_cnt = (uint16_t)(rxvq->vq_free_cnt - needed);
vq_ring_update_avail(rxvq, head_idx);
return 0;
}
static inline int __attribute__((always_inline))
virtqueue_enqueue_xmit(struct virtqueue *txvq, struct rte_mbuf *cookie)
{
const uint16_t needed = 2;
struct vring_desc *start_dp = txvq->vq_ring.desc;
uint16_t head_idx = txvq->vq_desc_head_idx;
uint16_t idx = head_idx;
struct vq_desc_extra *dxp;
if (unlikely(txvq->vq_free_cnt == 0))
return -ENOSPC;
if (unlikely(txvq->vq_free_cnt < needed))
return -EMSGSIZE;
if (unlikely(head_idx >= txvq->vq_nentries))
return -EFAULT;
dxp = &txvq->vq_descx[idx];
dxp->cookie = (void *)cookie;
dxp->ndescs = needed;
start_dp = txvq->vq_ring.desc;
start_dp[idx].addr = 0;
/*
* TODO: save one desc here?
*/
start_dp[idx].len = sizeof(struct virtio_net_hdr);
start_dp[idx].flags = VRING_DESC_F_NEXT;
start_dp[idx].addr = (uintptr_t)NULL;
idx = start_dp[idx].next;
start_dp[idx].addr = (uint64_t)rte_pktmbuf_mtod(cookie, uintptr_t);
start_dp[idx].len = cookie->data_len;
start_dp[idx].flags = 0;
idx = start_dp[idx].next;
txvq->vq_desc_head_idx = idx;
txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
vq_ring_update_avail(txvq, head_idx);
return 0;
}
static inline uint16_t __attribute__((always_inline))
virtqueue_dequeue_burst(struct virtqueue *vq, struct rte_mbuf **rx_pkts, uint32_t *len, uint16_t num)
{
struct vring_used_elem *uep;
struct rte_mbuf *cookie;
uint16_t used_idx, desc_idx;
uint16_t i;
/* Caller does the check */
for (i = 0; i < num ; i ++) {
used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
uep = &vq->vq_ring.used->ring[used_idx];
desc_idx = (uint16_t) uep->id;
cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
if (unlikely(cookie == NULL)) {
PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
vq->vq_used_cons_idx);
RTE_LOG(ERR, PMD, "%s: inconsistent (%u, %u)\n", __func__, used_idx , desc_idx);
break;
}
len[i] = uep->len;
rx_pkts[i] = cookie;
vq->vq_used_cons_idx++;
vq_ring_free_chain(vq, desc_idx);
vq->vq_descx[desc_idx].cookie = NULL;
}
return i;
}
#endif /* _VIRTQUEUE_H_ */