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| author | Jason Wang <jasowang@redhat.com> | 2020-09-07 18:49:02 +0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2020-09-29 02:14:29 -0400 |
| commit | b37556edec8372bef83959901fc142a272a7e1fa (patch) | |
| tree | fe0fc6c5fccfeff5a2ede0bcc43f35cf2412f9ea /include | |
| parent | e6546342a830e520d14ef03aa95677611de0d90c (diff) | |
| download | qemu-b37556edec8372bef83959901fc142a272a7e1fa.zip qemu-b37556edec8372bef83959901fc142a272a7e1fa.tar.gz qemu-b37556edec8372bef83959901fc142a272a7e1fa.tar.bz2 | |
vhost: switch to use IOTLB v2 format
This patch tries to switch to use new kernel IOTLB format V2. Previous
version may have inconsistent ABI between 32bit and 64bit machines
because of the hole after type field. Refer kernel commit
("429711aec282 vhost: switch to use new message format") for more
information.
To enable this feature, qemu need to use a new ioctl
VHOST_SET_BACKEND_FEATURE with VHOST_BACKEND_F_IOTLB_MSG_V2 bit. A new
vhost setting backend features ops was introduced. And when we try to
set features for vhost dev, we will examine the support of new IOTLB
format and enable it. This process is total transparent to guest,
which means we can have different IOTLB message type in src and dst
during migration.
The conversion of IOTLB message is straightforward, just check the
type and behave accordingly.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200907104903.31551-3-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/hw/virtio/vhost-backend.h | 2 | ||||
| -rw-r--r-- | include/hw/virtio/vhost.h | 1 |
2 files changed, 3 insertions, 0 deletions
diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h index 8825bd2..8a6f8e2 100644 --- a/include/hw/virtio/vhost-backend.h +++ b/include/hw/virtio/vhost-backend.h @@ -74,6 +74,7 @@ typedef int (*vhost_set_features_op)(struct vhost_dev *dev, uint64_t features); typedef int (*vhost_get_features_op)(struct vhost_dev *dev, uint64_t *features); +typedef int (*vhost_set_backend_cap_op)(struct vhost_dev *dev); typedef int (*vhost_set_owner_op)(struct vhost_dev *dev); typedef int (*vhost_reset_device_op)(struct vhost_dev *dev); typedef int (*vhost_get_vq_index_op)(struct vhost_dev *dev, int idx); @@ -146,6 +147,7 @@ typedef struct VhostOps { vhost_set_vring_busyloop_timeout_op vhost_set_vring_busyloop_timeout; vhost_set_features_op vhost_set_features; vhost_get_features_op vhost_get_features; + vhost_set_backend_cap_op vhost_set_backend_cap; vhost_set_owner_op vhost_set_owner; vhost_reset_device_op vhost_reset_device; vhost_get_vq_index_op vhost_get_vq_index; diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h index 767a95e..9458506 100644 --- a/include/hw/virtio/vhost.h +++ b/include/hw/virtio/vhost.h @@ -79,6 +79,7 @@ struct vhost_dev { uint64_t backend_features; uint64_t protocol_features; uint64_t max_queues; + uint64_t backend_cap; bool started; bool log_enabled; uint64_t log_size; |