qemu-e2k/include/hw/virtio/virtio-net.h
Michael S. Tsirkin 488f069bd1 virtio-net: add feature bit for any header s/g
Old qemu versions required that 1st s/g entry is the header.

Since QEMU 1.5, patchset titled "virtio-net: iovec handling cleanup"
removed this limitation but a feature bit is needed so guests know it's
safe to lay out header differently.

This patch applies on top and adds such a feature bit to QEMU.
It is set by default for virtio-net.
virtio net header inline with the data is beneficial
for latency and small packet bandwidth - guest driver
code utilizing this feature has been acked but missed 3.11
by a narrow margin, it's pending for 3.12.

This feature bit is cleared by default when compatibility with old
machine types is requested.

Other performance-sensitive devices (blk and scsi)
don't yet support arbitrary s/g layouts, so
we only set this bit for virtio-net for now.
There are plans to allow arbitrary layouts there, but
no code has been posted yet.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-07-15 21:26:26 +03:00

278 lines
10 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 "hw/virtio/virtio.h"
#include "hw/pci/pci.h"
#define TYPE_VIRTIO_NET "virtio-net-device"
#define VIRTIO_NET(obj) \
OBJECT_CHECK(VirtIONet, (obj), TYPE_VIRTIO_NET)
#define ETH_ALEN 6
/* from Linux's virtio_net.h */
/* The ID for virtio_net */
#define VIRTIO_ID_NET 1
/* The feature bitmap for virtio net */
#define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */
#define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum */
#define VIRTIO_NET_F_CTRL_GUEST_OFFLOADS 2 /* Control channel offload
* configuration support */
#define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */
#define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */
#define VIRTIO_NET_F_GUEST_TSO4 7 /* Guest can handle TSOv4 in. */
#define VIRTIO_NET_F_GUEST_TSO6 8 /* Guest can handle TSOv6 in. */
#define VIRTIO_NET_F_GUEST_ECN 9 /* Guest can handle TSO[6] w/ ECN in. */
#define VIRTIO_NET_F_GUEST_UFO 10 /* Guest can handle UFO in. */
#define VIRTIO_NET_F_HOST_TSO4 11 /* Host can handle TSOv4 in. */
#define VIRTIO_NET_F_HOST_TSO6 12 /* Host can handle TSOv6 in. */
#define VIRTIO_NET_F_HOST_ECN 13 /* Host can handle TSO[6] w/ ECN in. */
#define VIRTIO_NET_F_HOST_UFO 14 /* Host can handle UFO in. */
#define VIRTIO_NET_F_MRG_RXBUF 15 /* Host can merge receive buffers. */
#define VIRTIO_NET_F_STATUS 16 /* virtio_net_config.status available */
#define VIRTIO_NET_F_CTRL_VQ 17 /* Control channel available */
#define VIRTIO_NET_F_CTRL_RX 18 /* Control channel RX mode support */
#define VIRTIO_NET_F_CTRL_VLAN 19 /* Control channel VLAN filtering */
#define VIRTIO_NET_F_CTRL_RX_EXTRA 20 /* Extra RX mode control support */
#define VIRTIO_NET_F_MQ 22 /* Device supports Receive Flow
* Steering */
#define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */
#define VIRTIO_NET_S_LINK_UP 1 /* Link is up */
#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;
} 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))
struct virtio_net_config
{
/* The config defining mac address ($ETH_ALEN bytes) */
uint8_t mac[ETH_ALEN];
/* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
uint16_t status;
/* Max virtqueue pairs supported by the device */
uint16_t max_virtqueue_pairs;
} QEMU_PACKED;
/*
* Control virtqueue data structures
*
* The control virtqueue expects a header in the first sg entry
* and an ack/status response in the last entry. Data for the
* command goes in between.
*/
struct virtio_net_ctrl_hdr {
uint8_t class;
uint8_t cmd;
};
typedef uint8_t virtio_net_ctrl_ack;
#define VIRTIO_NET_OK 0
#define VIRTIO_NET_ERR 1
/*
* Control the RX mode, ie. promisucous, 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[][ETH_ALEN];
};
typedef struct VirtIONetQueue {
VirtQueue *rx_vq;
VirtQueue *tx_vq;
QEMUTimer *tx_timer;
QEMUBH *tx_bh;
int tx_waiting;
struct {
VirtQueueElement elem;
ssize_t len;
} 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;
uint8_t has_ufo;
int 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 {
int in_use;
int 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;
} VirtIONet;
#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 filterd by the hypervisor. Del is the
* opposite of add. Both commands expect an out entry containing a 2
* byte VLAN ID. VLAN filterting 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
/*
* Control Multiqueue
*
* The command VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
* enables multiqueue, specifying the number of the transmit and
* receive queues that will be used. After the command is consumed and acked by
* the device, the device will not steer new packets on receive virtqueues
* other than specified nor read from transmit virtqueues other than specified.
* Accordingly, driver should not transmit new packets on virtqueues other than
* specified.
*/
struct virtio_net_ctrl_mq {
uint16_t virtqueue_pairs;
};
#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
/*
* Control network offloads
*
* Dynamic offloads are available with the
* VIRTIO_NET_F_CTRL_GUEST_OFFLOADS feature bit.
*/
#define VIRTIO_NET_CTRL_GUEST_OFFLOADS 5
#define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET 0
#define DEFINE_VIRTIO_NET_FEATURES(_state, _field) \
DEFINE_VIRTIO_COMMON_FEATURES(_state, _field), \
DEFINE_PROP_BIT("any_layout", _state, _field, VIRTIO_F_ANY_LAYOUT, true), \
DEFINE_PROP_BIT("csum", _state, _field, VIRTIO_NET_F_CSUM, true), \
DEFINE_PROP_BIT("guest_csum", _state, _field, VIRTIO_NET_F_GUEST_CSUM, true), \
DEFINE_PROP_BIT("gso", _state, _field, VIRTIO_NET_F_GSO, true), \
DEFINE_PROP_BIT("guest_tso4", _state, _field, VIRTIO_NET_F_GUEST_TSO4, true), \
DEFINE_PROP_BIT("guest_tso6", _state, _field, VIRTIO_NET_F_GUEST_TSO6, true), \
DEFINE_PROP_BIT("guest_ecn", _state, _field, VIRTIO_NET_F_GUEST_ECN, true), \
DEFINE_PROP_BIT("guest_ufo", _state, _field, VIRTIO_NET_F_GUEST_UFO, true), \
DEFINE_PROP_BIT("host_tso4", _state, _field, VIRTIO_NET_F_HOST_TSO4, true), \
DEFINE_PROP_BIT("host_tso6", _state, _field, VIRTIO_NET_F_HOST_TSO6, true), \
DEFINE_PROP_BIT("host_ecn", _state, _field, VIRTIO_NET_F_HOST_ECN, true), \
DEFINE_PROP_BIT("host_ufo", _state, _field, VIRTIO_NET_F_HOST_UFO, true), \
DEFINE_PROP_BIT("mrg_rxbuf", _state, _field, VIRTIO_NET_F_MRG_RXBUF, true), \
DEFINE_PROP_BIT("status", _state, _field, VIRTIO_NET_F_STATUS, true), \
DEFINE_PROP_BIT("ctrl_vq", _state, _field, VIRTIO_NET_F_CTRL_VQ, true), \
DEFINE_PROP_BIT("ctrl_rx", _state, _field, VIRTIO_NET_F_CTRL_RX, true), \
DEFINE_PROP_BIT("ctrl_vlan", _state, _field, VIRTIO_NET_F_CTRL_VLAN, true), \
DEFINE_PROP_BIT("ctrl_rx_extra", _state, _field, VIRTIO_NET_F_CTRL_RX_EXTRA, true), \
DEFINE_PROP_BIT("ctrl_mac_addr", _state, _field, VIRTIO_NET_F_CTRL_MAC_ADDR, true), \
DEFINE_PROP_BIT("ctrl_guest_offloads", _state, _field, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true), \
DEFINE_PROP_BIT("mq", _state, _field, VIRTIO_NET_F_MQ, false)
#define DEFINE_VIRTIO_NET_PROPERTIES(_state, _field) \
DEFINE_PROP_UINT32("x-txtimer", _state, _field.txtimer, TX_TIMER_INTERVAL),\
DEFINE_PROP_INT32("x-txburst", _state, _field.txburst, TX_BURST), \
DEFINE_PROP_STRING("tx", _state, _field.tx)
void virtio_net_set_config_size(VirtIONet *n, uint32_t host_features);
void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
const char *type);
#endif