| Message ID | 20210602021043.39201-4-jasowang@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Packed virtqueue state support for vDPA | expand |
On Wed, Jun 02, 2021 at 10:10:42AM +0800, Jason Wang wrote: > We used to fail the set_vq_state() since it was not supported yet by > the virtio spec. But if the bus tries to set the state which is equal > to the device initial state after reset, we can let it go. > > This is a must for virtio_vdpa() to set vq state during probe which is > required for some vDPA parents. > > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > drivers/vdpa/virtio_pci/vp_vdpa.c | 42 ++++++++++++++++++++++++++++--- > 1 file changed, 39 insertions(+), 3 deletions(-) > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c > index c76ebb531212..18bf4a422772 100644 > --- a/drivers/vdpa/virtio_pci/vp_vdpa.c > +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c > @@ -210,13 +210,49 @@ static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid, > return -EOPNOTSUPP; > } > > +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa, > + const struct vdpa_vq_state *state) > +{ > + const struct vdpa_vq_state_split *split = &state->split; > + > + if (split->avail_index == 0) > + return 0; > + > + return -EOPNOTSUPP; > +} > + > +static int vp_vdpa_set_vq_state_packed(struct vdpa_device *vdpa, > + const struct vdpa_vq_state *state) > +{ > + const struct vdpa_vq_state_packed *packed = &state->packed; > + > + if (packed->last_avail_counter == 1 && Can you elaborate on the requirement on last_avail_counter and last_used_counter? > + packed->last_avail_idx == 0 && > + packed->last_used_counter == 1 && > + packed->last_used_idx == 0) > + return 0; > + > + return -EOPNOTSUPP; > +} > + > static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid, > const struct vdpa_vq_state *state) > { > - /* Note that this is not supported by virtio specification, so > - * we return -ENOPOTSUPP here. This means we can't support live > - * migration, vhost device start/stop. > + struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa); > + > + /* Note that this is not supported by virtio specification. > + * But if the state is by chance equal to the device initial > + * state, we can let it go. > */ > + if ((vp_modern_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK) && > + !vp_modern_get_queue_enable(mdev, qid)) { > + if (vp_modern_get_driver_features(mdev) & > + BIT_ULL(VIRTIO_F_RING_PACKED)) > + return vp_vdpa_set_vq_state_packed(vdpa, state); > + else > + return vp_vdpa_set_vq_state_split(vdpa, state); > + } > + > return -EOPNOTSUPP; > } > > -- > 2.25.1 >
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c index c76ebb531212..18bf4a422772 100644 --- a/drivers/vdpa/virtio_pci/vp_vdpa.c +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c @@ -210,13 +210,49 @@ static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid, return -EOPNOTSUPP; } +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa, + const struct vdpa_vq_state *state) +{ + const struct vdpa_vq_state_split *split = &state->split; + + if (split->avail_index == 0) + return 0; + + return -EOPNOTSUPP; +} + +static int vp_vdpa_set_vq_state_packed(struct vdpa_device *vdpa, + const struct vdpa_vq_state *state) +{ + const struct vdpa_vq_state_packed *packed = &state->packed; + + if (packed->last_avail_counter == 1 && + packed->last_avail_idx == 0 && + packed->last_used_counter == 1 && + packed->last_used_idx == 0) + return 0; + + return -EOPNOTSUPP; +} + static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid, const struct vdpa_vq_state *state) { - /* Note that this is not supported by virtio specification, so - * we return -ENOPOTSUPP here. This means we can't support live - * migration, vhost device start/stop. + struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa); + + /* Note that this is not supported by virtio specification. + * But if the state is by chance equal to the device initial + * state, we can let it go. */ + if ((vp_modern_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK) && + !vp_modern_get_queue_enable(mdev, qid)) { + if (vp_modern_get_driver_features(mdev) & + BIT_ULL(VIRTIO_F_RING_PACKED)) + return vp_vdpa_set_vq_state_packed(vdpa, state); + else + return vp_vdpa_set_vq_state_split(vdpa, state); + } + return -EOPNOTSUPP; }
We used to fail the set_vq_state() since it was not supported yet by the virtio spec. But if the bus tries to set the state which is equal to the device initial state after reset, we can let it go. This is a must for virtio_vdpa() to set vq state during probe which is required for some vDPA parents. Signed-off-by: Jason Wang <jasowang@redhat.com> --- drivers/vdpa/virtio_pci/vp_vdpa.c | 42 ++++++++++++++++++++++++++++--- 1 file changed, 39 insertions(+), 3 deletions(-)