numam-dpdk/drivers/net/virtio/virtqueue.h
Stephen Hemminger 6dc5de3a6a virtio: use indirect ring elements
The virtio ring in QEMU/KVM is usually limited to 256 entries
and the normal way that virtio driver was queuing mbufs required
nsegs + 1 ring elements. By using the indirect ring element feature
if available, each packet will take only one ring slot even for
multi-segment packets.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Acked-by: Huawei Xie <huawei.xie@intel.com>
2016-03-16 19:05:25 +01:00

345 lines
11 KiB
C

/*-
* 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
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _VIRTQUEUE_H_
#define _VIRTQUEUE_H_
#include <stdint.h>
#include <rte_atomic.h>
#include <rte_memory.h>
#include <rte_memzone.h>
#include <rte_mempool.h>
#include "virtio_pci.h"
#include "virtio_ring.h"
#include "virtio_logs.h"
struct rte_mbuf;
/*
* Per virtio_config.h in Linux.
* For virtio_pci on SMP, we don't need to order with respect to MMIO
* accesses through relaxed memory I/O windows, so smp_mb() et al are
* sufficient.
*
*/
#define virtio_mb() rte_smp_mb()
#define virtio_rmb() rte_smp_rmb()
#define virtio_wmb() rte_smp_wmb()
#ifdef RTE_PMD_PACKET_PREFETCH
#define rte_packet_prefetch(p) rte_prefetch1(p)
#else
#define rte_packet_prefetch(p) do {} while(0)
#endif
#define VIRTQUEUE_MAX_NAME_SZ 32
#define VTNET_SQ_RQ_QUEUE_IDX 0
#define VTNET_SQ_TQ_QUEUE_IDX 1
#define VTNET_SQ_CQ_QUEUE_IDX 2
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
/**
* Control the RX mode, ie. promiscuous, allmulti, etc...
* All commands require an "out" sg entry containing a 1 byte
* state value, zero = disable, non-zero = enable. Commands
* 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
* Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
*/
#define VIRTIO_NET_CTRL_RX 0
#define VIRTIO_NET_CTRL_RX_PROMISC 0
#define VIRTIO_NET_CTRL_RX_ALLMULTI 1
#define VIRTIO_NET_CTRL_RX_ALLUNI 2
#define VIRTIO_NET_CTRL_RX_NOMULTI 3
#define VIRTIO_NET_CTRL_RX_NOUNI 4
#define VIRTIO_NET_CTRL_RX_NOBCAST 5
/**
* Control the MAC
*
* The MAC filter table is managed by the hypervisor, the guest should
* assume the size is infinite. Filtering should be considered
* non-perfect, ie. based on hypervisor resources, the guest may
* received packets from sources not specified in the filter list.
*
* In addition to the class/cmd header, the TABLE_SET command requires
* two out scatterlists. Each contains a 4 byte count of entries followed
* by a concatenated byte stream of the ETH_ALEN MAC addresses. The
* first sg list contains unicast addresses, the second is for multicast.
* This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
* is available.
*
* The ADDR_SET command requests one out scatterlist, it contains a
* 6 bytes MAC address. This functionality is present if the
* VIRTIO_NET_F_CTRL_MAC_ADDR feature is available.
*/
struct virtio_net_ctrl_mac {
uint32_t entries;
uint8_t macs[][ETHER_ADDR_LEN];
} __attribute__((__packed__));
#define VIRTIO_NET_CTRL_MAC 1
#define VIRTIO_NET_CTRL_MAC_TABLE_SET 0
#define VIRTIO_NET_CTRL_MAC_ADDR_SET 1
/**
* Control VLAN filtering
*
* The VLAN filter table is controlled via a simple ADD/DEL interface.
* VLAN IDs not added may be filtered by the hypervisor. Del is the
* opposite of add. Both commands expect an out entry containing a 2
* byte VLAN ID. VLAN filtering is available with the
* VIRTIO_NET_F_CTRL_VLAN feature bit.
*/
#define VIRTIO_NET_CTRL_VLAN 2
#define VIRTIO_NET_CTRL_VLAN_ADD 0
#define VIRTIO_NET_CTRL_VLAN_DEL 1
struct virtio_net_ctrl_hdr {
uint8_t class;
uint8_t cmd;
} __attribute__((packed));
typedef uint8_t virtio_net_ctrl_ack;
#define VIRTIO_NET_OK 0
#define VIRTIO_NET_ERR 1
#define VIRTIO_MAX_CTRL_DATA 2048
struct virtio_pmd_ctrl {
struct virtio_net_ctrl_hdr hdr;
virtio_net_ctrl_ack status;
uint8_t data[VIRTIO_MAX_CTRL_DATA];
};
struct virtqueue {
struct virtio_hw *hw; /**< virtio_hw structure pointer. */
const struct rte_memzone *mz; /**< mem zone to populate RX ring. */
const struct rte_memzone *virtio_net_hdr_mz; /**< memzone to populate hdr. */
struct rte_mempool *mpool; /**< mempool for mbuf allocation */
uint16_t queue_id; /**< DPDK queue index. */
uint8_t port_id; /**< Device port identifier. */
uint16_t vq_queue_index; /**< PCI queue index */
void *vq_ring_virt_mem; /**< linear address of vring*/
unsigned int vq_ring_size;
phys_addr_t vq_ring_mem; /**< physical address of vring */
struct vring vq_ring; /**< vring keeping desc, used and avail */
uint16_t vq_free_cnt; /**< num of desc available */
uint16_t vq_nentries; /**< vring desc numbers */
uint16_t vq_free_thresh; /**< free threshold */
/**
* Head of the free chain in the descriptor table. If
* there are no free descriptors, this will be set to
* VQ_RING_DESC_CHAIN_END.
*/
uint16_t vq_desc_head_idx;
uint16_t vq_desc_tail_idx;
/**
* Last consumed descriptor in the used table,
* trails vq_ring.used->idx.
*/
uint16_t vq_used_cons_idx;
uint16_t vq_avail_idx;
uint64_t mbuf_initializer; /**< value to init mbufs. */
phys_addr_t virtio_net_hdr_mem; /**< hdr for each xmit packet */
struct rte_mbuf **sw_ring; /**< RX software ring. */
/* dummy mbuf, for wraparound when processing RX ring. */
struct rte_mbuf fake_mbuf;
/* Statistics */
uint64_t packets;
uint64_t bytes;
uint64_t errors;
uint64_t multicast;
uint64_t broadcast;
/* Size bins in array as RFC 2819, undersized [0], 64 [1], etc */
uint64_t size_bins[8];
uint16_t *notify_addr;
struct vq_desc_extra {
void *cookie;
uint16_t ndescs;
} vq_descx[0];
};
/* If multiqueue is provided by host, then we suppport it. */
#define VIRTIO_NET_CTRL_MQ 4
#define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET 0
#define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1
#define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000
#define VIRTIO_NET_CTRL_MAC_ADDR_SET 1
/**
* This is the first element of the scatter-gather list. If you don't
* specify GSO or CSUM features, you can simply ignore the header.
*/
struct virtio_net_hdr {
#define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /**< Use csum_start,csum_offset*/
uint8_t flags;
#define VIRTIO_NET_HDR_GSO_NONE 0 /**< Not a GSO frame */
#define VIRTIO_NET_HDR_GSO_TCPV4 1 /**< GSO frame, IPv4 TCP (TSO) */
#define VIRTIO_NET_HDR_GSO_UDP 3 /**< GSO frame, IPv4 UDP (UFO) */
#define VIRTIO_NET_HDR_GSO_TCPV6 4 /**< GSO frame, IPv6 TCP */
#define VIRTIO_NET_HDR_GSO_ECN 0x80 /**< TCP has ECN set */
uint8_t gso_type;
uint16_t hdr_len; /**< Ethernet + IP + tcp/udp hdrs */
uint16_t gso_size; /**< Bytes to append to hdr_len per frame */
uint16_t csum_start; /**< Position to start checksumming from */
uint16_t csum_offset; /**< Offset after that to place checksum */
};
/**
* This is the version of the header to use when the MRG_RXBUF
* feature has been negotiated.
*/
struct virtio_net_hdr_mrg_rxbuf {
struct virtio_net_hdr hdr;
uint16_t num_buffers; /**< Number of merged rx buffers */
};
/* Region reserved to allow for transmit header and indirect ring */
#define VIRTIO_MAX_TX_INDIRECT 8
struct virtio_tx_region {
struct virtio_net_hdr_mrg_rxbuf tx_hdr;
struct vring_desc tx_indir[VIRTIO_MAX_TX_INDIRECT]
__attribute__((__aligned__(16)));
};
/* Chain all the descriptors in the ring with an END */
static inline void
vring_desc_init(struct vring_desc *dp, uint16_t n)
{
uint16_t i;
for (i = 0; i < n - 1; i++)
dp[i].next = (uint16_t)(i + 1);
dp[i].next = VQ_RING_DESC_CHAIN_END;
}
/**
* Tell the backend not to interrupt us.
*/
void virtqueue_disable_intr(struct virtqueue *vq);
/**
* 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
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
vq_update_avail_idx(struct virtqueue *vq)
{
virtio_wmb();
vq->vq_ring.avail->idx = vq->vq_avail_idx;
}
static inline void
vq_update_avail_ring(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_avail_idx & (vq->vq_nentries - 1));
vq->vq_ring.avail->ring[avail_idx] = desc_idx;
vq->vq_avail_idx++;
}
static inline int
virtqueue_kick_prepare(struct virtqueue *vq)
{
return !(vq->vq_ring.used->flags & VRING_USED_F_NO_NOTIFY);
}
static inline void
virtqueue_notify(struct virtqueue *vq)
{
/*
* Ensure updated avail->idx is visible to host.
* For virtio on IA, the notificaiton is through io port operation
* which is a serialization instruction itself.
*/
vq->hw->vtpci_ops->notify_queue(vq->hw, vq);
}
#ifdef RTE_LIBRTE_VIRTIO_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: - 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", \
(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
#endif /* _VIRTQUEUE_H_ */