net: Consolidate vhost feature bits into vhost_net structure

Previously, the vhost_net_get_feature_bits() function in
hw/net/vhost_net.c used a large switch statement to determine
the appropriate feature bits based on the NetClientDriver type.

This created unnecessary coupling between the generic vhost layer
and specific network backends (like TAP, vhost-user, and
vhost-vdpa).

This patch moves the definition of vhost feature bits directly into the
vhost_net structure for each relevant network client.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Laurent Vivier 2025-07-09 10:24:19 +02:00 committed by Jason Wang
parent 8f6e5c620a
commit effdacbf28
7 changed files with 69 additions and 90 deletions

View file

@ -42,11 +42,29 @@
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/sockets.h"
#include "hw/virtio/vhost.h"
#include "net/tap.h"
#include "net/vhost_net.h"
static const int kernel_feature_bits[] = {
VIRTIO_F_NOTIFY_ON_EMPTY,
VIRTIO_RING_F_INDIRECT_DESC,
VIRTIO_RING_F_EVENT_IDX,
VIRTIO_NET_F_MRG_RXBUF,
VIRTIO_F_VERSION_1,
VIRTIO_NET_F_MTU,
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_RING_PACKED,
VIRTIO_F_RING_RESET,
VIRTIO_F_IN_ORDER,
VIRTIO_F_NOTIFICATION_DATA,
VIRTIO_NET_F_RSC_EXT,
VIRTIO_NET_F_HASH_REPORT,
VHOST_INVALID_FEATURE_BIT
};
typedef struct TAPState {
NetClientState nc;
int fd;
@ -725,6 +743,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
}
options.opaque = (void *)(uintptr_t)vhostfd;
options.nvqs = 2;
options.feature_bits = kernel_feature_bits;
s->vhost_net = vhost_net_init(&options);
if (!s->vhost_net) {

View file

@ -12,7 +12,9 @@
#include "clients.h"
#include "net/vhost_net.h"
#include "net/vhost-user.h"
#include "hw/virtio/vhost.h"
#include "hw/virtio/vhost-user.h"
#include "standard-headers/linux/virtio_net.h"
#include "chardev/char-fe.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-net.h"
@ -22,6 +24,46 @@
#include "qemu/option.h"
#include "trace.h"
static const int user_feature_bits[] = {
VIRTIO_F_NOTIFY_ON_EMPTY,
VIRTIO_F_NOTIFICATION_DATA,
VIRTIO_RING_F_INDIRECT_DESC,
VIRTIO_RING_F_EVENT_IDX,
VIRTIO_F_ANY_LAYOUT,
VIRTIO_F_VERSION_1,
VIRTIO_NET_F_CSUM,
VIRTIO_NET_F_GUEST_CSUM,
VIRTIO_NET_F_GSO,
VIRTIO_NET_F_GUEST_TSO4,
VIRTIO_NET_F_GUEST_TSO6,
VIRTIO_NET_F_GUEST_ECN,
VIRTIO_NET_F_GUEST_UFO,
VIRTIO_NET_F_HOST_TSO4,
VIRTIO_NET_F_HOST_TSO6,
VIRTIO_NET_F_HOST_ECN,
VIRTIO_NET_F_HOST_UFO,
VIRTIO_NET_F_MRG_RXBUF,
VIRTIO_NET_F_MTU,
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_RING_PACKED,
VIRTIO_F_RING_RESET,
VIRTIO_F_IN_ORDER,
VIRTIO_NET_F_RSS,
VIRTIO_NET_F_RSC_EXT,
VIRTIO_NET_F_HASH_REPORT,
VIRTIO_NET_F_GUEST_USO4,
VIRTIO_NET_F_GUEST_USO6,
VIRTIO_NET_F_HOST_USO,
/* This bit implies RARP isn't sent by QEMU out of band */
VIRTIO_NET_F_GUEST_ANNOUNCE,
VIRTIO_NET_F_MQ,
VHOST_INVALID_FEATURE_BIT
};
typedef struct NetVhostUserState {
NetClientState nc;
CharBackend chr; /* only queue index 0 */
@ -96,6 +138,7 @@ static int vhost_user_start(int queues, NetClientState *ncs[],
options.opaque = be;
options.busyloop_timeout = 0;
options.nvqs = 2;
options.feature_bits = user_feature_bits;
net = vhost_net_init(&options);
if (!net) {
error_report("failed to init vhost_net for queue %d", i);

View file

@ -55,7 +55,7 @@ typedef struct VhostVDPAState {
* with the exception of VHOST_INVALID_FEATURE_BIT,
* which should always be the last entry.
*/
const int vdpa_feature_bits[] = {
static const int vdpa_feature_bits[] = {
VIRTIO_F_ANY_LAYOUT,
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_NOTIFY_ON_EMPTY,
@ -201,6 +201,7 @@ static int vhost_vdpa_add(NetClientState *ncs, void *be,
options.opaque = be;
options.busyloop_timeout = 0;
options.nvqs = nvqs;
options.feature_bits = vdpa_feature_bits;
net = vhost_net_init(&options);
if (!net) {