qemu/include/hw/virtio/virtio-net.h
Maxime Coquelin 75ebec11af virtio_net: Bypass backends for MTU feature negotiation
This patch adds a new internal "x-mtu-bypass-backend" property
to bypass backends for MTU feature negotiation.

When this property is set, the MTU feature is negotiated as soon
as supported by the guest and a MTU value is set via the host_mtu
parameter. In case the backend advertises the feature (e.g. DPDK's
vhost-user backend), the feature negotiation is propagated down to
the backend.

When this property is not set, the backend has to support the MTU
feature for its negotiation to succeed.

For compatibility purpose, this property is disabled for machine
types v2.9 and older.

Cc: Aaron Conole <aconole@redhat.com>
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Vlad Yasevich <vyasevic@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-25 21:25:28 +03:00

107 lines
2.6 KiB
C

/*
* Virtio Network Device
*
* Copyright IBM, Corp. 2007
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_VIRTIO_NET_H
#define QEMU_VIRTIO_NET_H
#include "standard-headers/linux/virtio_net.h"
#include "hw/virtio/virtio.h"
#define TYPE_VIRTIO_NET "virtio-net-device"
#define VIRTIO_NET(obj) \
OBJECT_CHECK(VirtIONet, (obj), TYPE_VIRTIO_NET)
#define TX_TIMER_INTERVAL 150000 /* 150 us */
/* Limit the number of packets that can be sent via a single flush
* of the TX queue. This gives us a guaranteed exit condition and
* ensures fairness in the io path. 256 conveniently matches the
* length of the TX queue and shows a good balance of performance
* and latency. */
#define TX_BURST 256
typedef struct virtio_net_conf
{
uint32_t txtimer;
int32_t txburst;
char *tx;
uint16_t rx_queue_size;
uint16_t mtu;
} virtio_net_conf;
/* Maximum packet size we can receive from tap device: header + 64k */
#define VIRTIO_NET_MAX_BUFSIZE (sizeof(struct virtio_net_hdr) + (64 << 10))
typedef struct VirtIONetQueue {
VirtQueue *rx_vq;
VirtQueue *tx_vq;
QEMUTimer *tx_timer;
QEMUBH *tx_bh;
uint32_t tx_waiting;
struct {
VirtQueueElement *elem;
} async_tx;
struct VirtIONet *n;
} VirtIONetQueue;
typedef struct VirtIONet {
VirtIODevice parent_obj;
uint8_t mac[ETH_ALEN];
uint16_t status;
VirtIONetQueue *vqs;
VirtQueue *ctrl_vq;
NICState *nic;
uint32_t tx_timeout;
int32_t tx_burst;
uint32_t has_vnet_hdr;
size_t host_hdr_len;
size_t guest_hdr_len;
uint32_t host_features;
uint8_t has_ufo;
uint32_t mergeable_rx_bufs;
uint8_t promisc;
uint8_t allmulti;
uint8_t alluni;
uint8_t nomulti;
uint8_t nouni;
uint8_t nobcast;
uint8_t vhost_started;
struct {
uint32_t in_use;
uint32_t first_multi;
uint8_t multi_overflow;
uint8_t uni_overflow;
uint8_t *macs;
} mac_table;
uint32_t *vlans;
virtio_net_conf net_conf;
NICConf nic_conf;
DeviceState *qdev;
int multiqueue;
uint16_t max_queues;
uint16_t curr_queues;
size_t config_size;
char *netclient_name;
char *netclient_type;
uint64_t curr_guest_offloads;
QEMUTimer *announce_timer;
int announce_counter;
bool needs_vnet_hdr_swap;
bool mtu_bypass_backend;
} VirtIONet;
void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
const char *type);
#endif