| Message ID | 1528225683-11413-9-git-send-email-wexu@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC,v2,1/8] virtio: feature bit, data structure, init for 1.1 | expand |
On 2018年06月06日 03:08, wexu@redhat.com wrote: > From: Wei Xu <wexu@redhat.com> > > last_avail, avail_wrap_count, used_idx and used_wrap_count are > needed to support vhost-net backend, all these are either 16 or > bool variables, since state.num is 64bit wide, so here it is > possible to put them to the 'num' without introducing a new case > while handling ioctl. > > Unload/Reload test has been done successfully with a patch in vhost kernel. You need a patch to enable vhost. And I think you can only do it for vhost-kenrel now since vhost-user protocol needs some extension I believe. > > Signed-off-by: Wei Xu <wexu@redhat.com> > --- > hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- > 1 file changed, 34 insertions(+), 8 deletions(-) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 4543974..153f6d7 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -2862,33 +2862,59 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) > } > } > > -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > { > - return vdev->vq[n].last_avail_idx; > + uint64_t num; > + > + num = vdev->vq[n].last_avail_idx; > + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; > + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; > + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; So s.num is 32bit, I don't think this can even work. Thanks > + } > + > + return num; > } > > -void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) > +void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint64_t num) > { > - vdev->vq[n].last_avail_idx = idx; > - vdev->vq[n].shadow_avail_idx = idx; > + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx = (uint16_t)(num); > + > + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > + vdev->vq[n].avail_wrap_counter = (uint16_t)(num >> 16); > + vdev->vq[n].used_idx = (uint16_t)(num >> 32); > + vdev->vq[n].used_wrap_counter = (uint16_t)(num >> 48); > + } > } > > void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) > { > rcu_read_lock(); > - if (vdev->vq[n].vring.desc) { > + if (!vdev->vq[n].vring.desc) { > + goto out; > + } > + > + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > vdev->vq[n].last_avail_idx = vring_used_idx(&vdev->vq[n]); > - vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; > } > + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; > + > +out: > rcu_read_unlock(); > } > > void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) > { > rcu_read_lock(); > - if (vdev->vq[n].vring.desc) { > + if (!vdev->vq[n].vring.desc) { > + goto out; > + } > + > + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]); > } > + > +out: > rcu_read_unlock(); > } >
On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote: > > > On 2018年06月06日 03:08, wexu@redhat.com wrote: > >From: Wei Xu <wexu@redhat.com> > > > >last_avail, avail_wrap_count, used_idx and used_wrap_count are > >needed to support vhost-net backend, all these are either 16 or > >bool variables, since state.num is 64bit wide, so here it is > >possible to put them to the 'num' without introducing a new case > >while handling ioctl. > > > >Unload/Reload test has been done successfully with a patch in vhost kernel. > > You need a patch to enable vhost. > > And I think you can only do it for vhost-kenrel now since vhost-user > protocol needs some extension I believe. OK. > > > > >Signed-off-by: Wei Xu <wexu@redhat.com> > >--- > > hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- > > 1 file changed, 34 insertions(+), 8 deletions(-) > > > >diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > >index 4543974..153f6d7 100644 > >--- a/hw/virtio/virtio.c > >+++ b/hw/virtio/virtio.c > >@@ -2862,33 +2862,59 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) > > } > > } > >-uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > >+uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > > { > >- return vdev->vq[n].last_avail_idx; > >+ uint64_t num; > >+ > >+ num = vdev->vq[n].last_avail_idx; > >+ if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > >+ num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; > >+ num |= ((uint64_t)vdev->vq[n].used_idx) << 32; > >+ num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; > > So s.num is 32bit, I don't think this can even work. I mistakenly checked out s.num is 64bit, will add a new case in next version. Wei > > Thanks > > >+ } > >+ > >+ return num; > > } > >-void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) > >+void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint64_t num) > > { > >- vdev->vq[n].last_avail_idx = idx; > >- vdev->vq[n].shadow_avail_idx = idx; > >+ vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx = (uint16_t)(num); > >+ > >+ if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > >+ vdev->vq[n].avail_wrap_counter = (uint16_t)(num >> 16); > >+ vdev->vq[n].used_idx = (uint16_t)(num >> 32); > >+ vdev->vq[n].used_wrap_counter = (uint16_t)(num >> 48); > >+ } > > } > > void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) > > { > > rcu_read_lock(); > >- if (vdev->vq[n].vring.desc) { > >+ if (!vdev->vq[n].vring.desc) { > >+ goto out; > >+ } > >+ > >+ if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > > vdev->vq[n].last_avail_idx = vring_used_idx(&vdev->vq[n]); > >- vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; > > } > >+ vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; > >+ > >+out: > > rcu_read_unlock(); > > } > > void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) > > { > > rcu_read_lock(); > >- if (vdev->vq[n].vring.desc) { > >+ if (!vdev->vq[n].vring.desc) { > >+ goto out; > >+ } > >+ > >+ if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > > vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]); > > } > >+ > >+out: > > rcu_read_unlock(); > > } >
Hi Wei, Jason, On 06/19/2018 09:53 AM, Wei Xu wrote: > On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote: >> >> >> On 2018年06月06日 03:08, wexu@redhat.com wrote: >>> From: Wei Xu <wexu@redhat.com> >>> >>> last_avail, avail_wrap_count, used_idx and used_wrap_count are >>> needed to support vhost-net backend, all these are either 16 or >>> bool variables, since state.num is 64bit wide, so here it is >>> possible to put them to the 'num' without introducing a new case >>> while handling ioctl. >>> >>> Unload/Reload test has been done successfully with a patch in vhost kernel. >> >> You need a patch to enable vhost. >> >> And I think you can only do it for vhost-kenrel now since vhost-user >> protocol needs some extension I believe. > > OK. > >> >>> >>> Signed-off-by: Wei Xu <wexu@redhat.com> >>> --- >>> hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- >>> 1 file changed, 34 insertions(+), 8 deletions(-) >>> >>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c >>> index 4543974..153f6d7 100644 >>> --- a/hw/virtio/virtio.c >>> +++ b/hw/virtio/virtio.c >>> @@ -2862,33 +2862,59 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) >>> } >>> } >>> -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>> +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>> { >>> - return vdev->vq[n].last_avail_idx; >>> + uint64_t num; >>> + >>> + num = vdev->vq[n].last_avail_idx; >>> + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>> + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; >>> + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; >>> + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; >> >> So s.num is 32bit, I don't think this can even work. > > I mistakenly checked out s.num is 64bit, will add a new case in next version. Wouldn't be enough to just get/set avail_wrap_counter? Something like this so that it fits into 32 bits: if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 31; } Regards, Maxime > > Wei > >> >> Thanks >> >>> + } >>> + >>> + return num; >>> } >>> -void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) >>> +void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint64_t num) >>> { >>> - vdev->vq[n].last_avail_idx = idx; >>> - vdev->vq[n].shadow_avail_idx = idx; >>> + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx = (uint16_t)(num); >>> + >>> + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>> + vdev->vq[n].avail_wrap_counter = (uint16_t)(num >> 16); >>> + vdev->vq[n].used_idx = (uint16_t)(num >> 32); >>> + vdev->vq[n].used_wrap_counter = (uint16_t)(num >> 48); >>> + } >>> } >>> void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) >>> { >>> rcu_read_lock(); >>> - if (vdev->vq[n].vring.desc) { >>> + if (!vdev->vq[n].vring.desc) { >>> + goto out; >>> + } >>> + >>> + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>> vdev->vq[n].last_avail_idx = vring_used_idx(&vdev->vq[n]); >>> - vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; >>> } >>> + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; >>> + >>> +out: >>> rcu_read_unlock(); >>> } >>> void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) >>> { >>> rcu_read_lock(); >>> - if (vdev->vq[n].vring.desc) { >>> + if (!vdev->vq[n].vring.desc) { >>> + goto out; >>> + } >>> + >>> + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>> vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]); >>> } >>> + >>> +out: >>> rcu_read_unlock(); >>> } >> >
On 2018年09月21日 04:39, Maxime Coquelin wrote: > Hi Wei, Jason, > > On 06/19/2018 09:53 AM, Wei Xu wrote: >> On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote: >>> >>> >>> On 2018å¹´06月06æ—¥ 03:08, wexu@redhat.com wrote: >>>> From: Wei Xu <wexu@redhat.com> >>>> >>>> last_avail, avail_wrap_count, used_idx and used_wrap_count are >>>> needed to support vhost-net backend, all these are either 16 or >>>> bool variables, since state.num is 64bit wide, so here it is >>>> possible to put them to the 'num' without introducing a new case >>>> while handling ioctl. >>>> >>>> Unload/Reload test has been done successfully with a patch in vhost >>>> kernel. >>> >>> You need a patch to enable vhost. >>> >>> And I think you can only do it for vhost-kenrel now since vhost-user >>> protocol needs some extension I believe. >> >> OK. >> >>> >>>> >>>> Signed-off-by: Wei Xu <wexu@redhat.com> >>>> --- >>>> hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- >>>> 1 file changed, 34 insertions(+), 8 deletions(-) >>>> >>>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c >>>> index 4543974..153f6d7 100644 >>>> --- a/hw/virtio/virtio.c >>>> +++ b/hw/virtio/virtio.c >>>> @@ -2862,33 +2862,59 @@ hwaddr >>>> virtio_queue_get_used_size(VirtIODevice *vdev, int n) >>>> } >>>> } >>>> -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>>> +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>>> { >>>> - return vdev->vq[n].last_avail_idx; >>>> + uint64_t num; >>>> + >>>> + num = vdev->vq[n].last_avail_idx; >>>> + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>>> + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; >>>> + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; >>>> + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; >>> >>> So s.num is 32bit, I don't think this can even work. >> >> I mistakenly checked out s.num is 64bit, will add a new case in next >> version. > > Wouldn't be enough to just get/set avail_wrap_counter? > Something like this so that it fits into 32 bits: > if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 31; > } > > > Regards, > Maxime Yes, actually, that's what I did for vhost kernel (https://github.com/jasowang/net/blob/packed-host/drivers/vhost/vhost.c#L1418) Thanks
On 09/21/2018 04:33 AM, Jason Wang wrote: > > > On 2018年09月21日 04:39, Maxime Coquelin wrote: >> Hi Wei, Jason, >> >> On 06/19/2018 09:53 AM, Wei Xu wrote: >>> On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote: >>>> >>>> >>>> On 2018å¹´06月06æ—¥ 03:08, wexu@redhat.com wrote: >>>>> From: Wei Xu <wexu@redhat.com> >>>>> >>>>> last_avail, avail_wrap_count, used_idx and used_wrap_count are >>>>> needed to support vhost-net backend, all these are either 16 or >>>>> bool variables, since state.num is 64bit wide, so here it is >>>>> possible to put them to the 'num' without introducing a new case >>>>> while handling ioctl. >>>>> >>>>> Unload/Reload test has been done successfully with a patch in vhost >>>>> kernel. >>>> >>>> You need a patch to enable vhost. >>>> >>>> And I think you can only do it for vhost-kenrel now since vhost-user >>>> protocol needs some extension I believe. >>> >>> OK. >>> >>>> >>>>> >>>>> Signed-off-by: Wei Xu <wexu@redhat.com> >>>>> --- >>>>> hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- >>>>> 1 file changed, 34 insertions(+), 8 deletions(-) >>>>> >>>>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c >>>>> index 4543974..153f6d7 100644 >>>>> --- a/hw/virtio/virtio.c >>>>> +++ b/hw/virtio/virtio.c >>>>> @@ -2862,33 +2862,59 @@ hwaddr >>>>> virtio_queue_get_used_size(VirtIODevice *vdev, int n) >>>>> } >>>>> } >>>>> -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>>>> +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) >>>>> { >>>>> - return vdev->vq[n].last_avail_idx; >>>>> + uint64_t num; >>>>> + >>>>> + num = vdev->vq[n].last_avail_idx; >>>>> + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >>>>> + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; >>>>> + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; >>>>> + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; >>>> >>>> So s.num is 32bit, I don't think this can even work. >>> >>> I mistakenly checked out s.num is 64bit, will add a new case in next >>> version. >> >> Wouldn't be enough to just get/set avail_wrap_counter? >> Something like this so that it fits into 32 bits: >> if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { >> num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 31; >> } >> >> >> Regards, >> Maxime > > Yes, actually, that's what I did for vhost kernel > (https://github.com/jasowang/net/blob/packed-host/drivers/vhost/vhost.c#L1418) Oh yes, I forgot on what I based my implementation on. Wei, Michael, do you agree with this? I will need to merge the Vhost patch in DPDK in the coming two weeks. Regards, Maxime > > Thanks
On Fri, Sep 21, 2018 at 09:30:26AM +0200, Maxime Coquelin wrote: > > > On 09/21/2018 04:33 AM, Jason Wang wrote: > > > > > > On 2018年09月21日 04:39, Maxime Coquelin wrote: > > > Hi Wei, Jason, > > > > > > On 06/19/2018 09:53 AM, Wei Xu wrote: > > > > On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote: > > > > > > > > > > > > > > > On 2018å¹´06月06æ—¥ 03:08, wexu@redhat.com wrote: > > > > > > From: Wei Xu <wexu@redhat.com> > > > > > > > > > > > > last_avail, avail_wrap_count, used_idx and used_wrap_count are > > > > > > needed to support vhost-net backend, all these are either 16 or > > > > > > bool variables, since state.num is 64bit wide, so here it is > > > > > > possible to put them to the 'num' without introducing a new case > > > > > > while handling ioctl. > > > > > > > > > > > > Unload/Reload test has been done successfully with a > > > > > > patch in vhost kernel. > > > > > > > > > > You need a patch to enable vhost. > > > > > > > > > > And I think you can only do it for vhost-kenrel now since vhost-user > > > > > protocol needs some extension I believe. > > > > > > > > OK. > > > > > > > > > > > > > > > > > > > > > Signed-off-by: Wei Xu <wexu@redhat.com> > > > > > > --- > > > > > > hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++-------- > > > > > > 1 file changed, 34 insertions(+), 8 deletions(-) > > > > > > > > > > > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > > > > > > index 4543974..153f6d7 100644 > > > > > > --- a/hw/virtio/virtio.c > > > > > > +++ b/hw/virtio/virtio.c > > > > > > @@ -2862,33 +2862,59 @@ hwaddr > > > > > > virtio_queue_get_used_size(VirtIODevice *vdev, int n) > > > > > > } > > > > > > } > > > > > > -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > > > > > > +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) > > > > > > { > > > > > > - return vdev->vq[n].last_avail_idx; > > > > > > + uint64_t num; > > > > > > + > > > > > > + num = vdev->vq[n].last_avail_idx; > > > > > > + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > > > > > > + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; > > > > > > + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; > > > > > > + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; > > > > > > > > > > So s.num is 32bit, I don't think this can even work. > > > > > > > > I mistakenly checked out s.num is 64bit, will add a new case in > > > > next version. > > > > > > Wouldn't be enough to just get/set avail_wrap_counter? > > > Something like this so that it fits into 32 bits: > > > if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > > > num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 31; > > > } > > > > > > > > > Regards, > > > Maxime > > > > Yes, actually, that's what I did for vhost kernel (https://github.com/jasowang/net/blob/packed-host/drivers/vhost/vhost.c#L1418) > > Oh yes, I forgot on what I based my implementation on. > Wei, Michael, do you agree with this? I will need to merge the Vhost > patch in DPDK in the coming two weeks. > > Regards, > Maxime It looks reasonable to me. > > > > Thanks
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 4543974..153f6d7 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2862,33 +2862,59 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) } } -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) +uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) { - return vdev->vq[n].last_avail_idx; + uint64_t num; + + num = vdev->vq[n].last_avail_idx; + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16; + num |= ((uint64_t)vdev->vq[n].used_idx) << 32; + num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48; + } + + return num; } -void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) +void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint64_t num) { - vdev->vq[n].last_avail_idx = idx; - vdev->vq[n].shadow_avail_idx = idx; + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx = (uint16_t)(num); + + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + vdev->vq[n].avail_wrap_counter = (uint16_t)(num >> 16); + vdev->vq[n].used_idx = (uint16_t)(num >> 32); + vdev->vq[n].used_wrap_counter = (uint16_t)(num >> 48); + } } void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) { rcu_read_lock(); - if (vdev->vq[n].vring.desc) { + if (!vdev->vq[n].vring.desc) { + goto out; + } + + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { vdev->vq[n].last_avail_idx = vring_used_idx(&vdev->vq[n]); - vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; } + vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; + +out: rcu_read_unlock(); } void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) { rcu_read_lock(); - if (vdev->vq[n].vring.desc) { + if (!vdev->vq[n].vring.desc) { + goto out; + } + + if (!virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]); } + +out: rcu_read_unlock(); }